Abstract: A reed switch includes an envelope, a first fixed terminal piece, a second fixed terminal piece, a third fixed terminal piece, a movable reed piece, a first spring member, a second spring member, and a third spring member. The movable reed piece has a base end portion, a distal end portion, and a movable contact portion. A distal end portion of the second spring member is farther from the first spring member than a base end portion of the second spring member in a state where the movable contact portion is spaced apart from a distal end portion of the first spring member and the distal end portion of the second spring member.

Abstract: A reed switch includes an envelope. First and second fixed terminal pieces are at one end of the envelope. A third fixed terminal piece is at another end of the envelope. A movable reed piece has a base end portion facing the one end portion of the third fixed terminal piece across a magnetic gap, a distal end portion to contact the first fixed terminal piece, and a movable contact portion. A first spring member has a base end portion secured to the first fixed terminal piece and a distal end portion to contact the movable contact portion. A second spring member has a base end portion secured to the second fixed terminal piece and a distal end portion to contact the movable contact portion. A third spring member has one and another end portions respectively secured to the movable reed piece and the third fixed terminal piece.

Abstract: A reed switch includes an envelope, a first fixed terminal piece, a second fixed terminal piece, a third fixed terminal piece, a movable reed piece, a first spring member, a second spring member, and a third spring member. The movable reed piece has a base end portion, a distal end portion, and a movable contact portion. A distal end portion of the second spring member is farther from the first spring member than a base end portion of the second spring member in a state where the movable contact portion is spaced apart from a distal end portion of the first spring member and the distal end portion of the second spring member.

Abstract: A reed switch includes an envelope. First and second fixed terminal pieces are at one end of the envelope. A third fixed terminal piece is at another end of the envelope. A movable reed piece has a base end portion facing the one end portion of the third fixed terminal piece across a magnetic gap, a distal end portion to contact the first fixed terminal piece, and a movable contact portion. A first spring member has a base end portion secured to the first fixed terminal piece and a distal end portion to contact the movable contact portion. A second spring member has a base end portion secured to the second fixed terminal piece and a distal end portion to contact the movable contact portion. A third spring member has one and another end portions respectively secured to the movable reed piece and the third fixed terminal piece.

Abstract: A parabolic antenna dish has a circumferential reinforcement flange portion defined by a ridge line which is devoid of air holes and a mesh plate portion integrally connected to the inner periphery of the reinforcement flange portion, the mesh plate portion having as many air holes as possible formed in a region which is not smaller than 80% in terms of the radius of the radiowave reflecting surface.

Abstract: A fluid pressure reducing device having a core provided with a peripheral spiral groove and a pipe receiving the core. The portion of the pipe receiving the core is radially contracted so that the ridges of the spiral groove of the core intrude into the inner peripheral surface of the pipe, thereby to form a spiral passage between the pipe and the core. The pressure of a fluid is reduced as the latter flows through the spiral passage. This fluid pressure reducing device is easy to produce and permits an easy fine adjustment of the flow resistance.

Abstract: An internal groove forming apparatus for heat exchanging pipes, having a cylindrical holder adapted to be loosely fitted in a heat exchanging pipe in concentric relationship, and a plurality of groove forming rolling tools arranged on the holder in a plurality of axially spaced, circumferentially oriented rows and rotatably supported on the holder in such a manner that the rolling tools of one of the two adjacent rows are disposed in staggered relationship with respect to those of the other and an imaginary circle circumscribing the rolling tools is interposed between an outer peripheral surface and an inner peripheral surface of the heat exchanging pipe. Axial relative movements of the heat exchanging pipe and the holder enable the rolling tools to form a number of substantially axially oriented grooves on the inner peripheral surface of the heat exchanging pipe.