Patent ID: 8659375

Claim:
A reed switch comprising: an envelope having one end and another end; a first fixed terminal piece at the one end of the envelope, the first fixed terminal piece having one end portion inside the envelope and another end portion outside the envelope; a second fixed terminal piece spaced apart from the first fixed terminal piece at the one end of the envelope, the second fixed terminal piece having one end portion inside the envelope and another end portion outside the envelope; a third fixed terminal piece at the other end of the envelope, the third fixed terminal piece having one end portion inside the envelope and another end portion outside the envelope; a movable reed piece inside the envelope, the movable reed piece having a base end portion, a distal end portion, and a movable contact portion, the base end portion facing the one end portion of the third fixed terminal piece across a magnetic gap, the distal end portion being configured to come into contact with the first fixed terminal piece, the movable contact portion being further centerward than the distal end portion in a longitudinal direction of the reed switch; a first spring member having a base end portion secured to the first fixed terminal piece and a distal end portion configured to come into contact with the movable contact portion; a second spring member having a base end portion secured to the second fixed terminal piece and a distal end portion configured to come into contact with the movable contact portion; and a third spring member having one end portion secured to the movable reed piece and another end portion secured to the third fixed terminal piece, wherein the first spring member, the second spring member, and the third spring member each have a different spring constant, and wherein the distal end portion of the movable reed piece is configured to not come into direct contact with the second fixed terminal.