A case is formed by an upper case and a lower case, and a buzzer is provided in the case. Two coil springs are securely mounted in holes formed in the lower case. A lower portion of the coil spring is projected from an underside of the lower case. A pair of leads electrically connect both ends of the coil to the coil springs, respectively.

An electromagnetic audio transducer for SMD applications. The transducer comprises a lead frame with external terminals, which are formed into a predetermined shape. The transducer has a case with inside and outside surfaces, where the case is integrated with the lead frame to expose the external terminals at its outside surface. The transducer has solder bases formed by exposing the lead frame at the inside surface of the case. The drive section of the transducer has a coil arranged inside the case, with the coil having coil terminals, and the coil terminals are led to the solder bases for electrical connection at the inside surface of the case.

A speaker has a frame provided with a yoke, a magnet, a vibrating plate and a voice coil, and a pair of leads. An end of each of the leads is connected to an end of the coil and the other end portion of the lead is exposed in a hole formed in the frame and secured to the frame so as to be connected to an outside terminal. A terminal connecting device is provided for connecting the other end of the lead to the outside terminal. The terminal connecting device comprises a cylindrical case secured in the hole of the frame, a connecting rod slidably mounted in the cylindrical case, and a coil spring provided in the cylindrical case to outwardly urge the connecting rod so as to be contacted with the outside terminal at an end of the rod. A top end of the cylindrical case is contacted with the end portion of the lead.

An improved structure of magnet type sounder of an electronic acoustic alarm mounted on the engine of a car, wherein primarily, a sound emitting circuit board is placed on an acoustic pipe of a supporting plate, and a magnet is held in a housing formed by an encircling plate beneath the supporting plate, and a sound transmitting case is formed as a flare on the bottom portion thereof which is convex in the inward direction to form a spherical dome surface of which an acoustic pipe column is telescopically placed over the acoustic pipe of the supporting plate, this assembly is then placed in a main case body, and further an acoustic resonant lid covers a through hole of the acoustic pipe column of the sound transmitting case, so that an object of volume reducing can be achieved,

An electromagnetic sound generator has a case provided with a yoke, a magnet, a vibrating plate and a coil, and a pair of leads. An end of the coil and the other end of the leads is secured to the case so as to be connected to an outside terminal. A terminal connecting device is provided for connecting the end of the lead to the outside terminal. The terminal connecting device comprises a cylindrical case secured to the case, a connecting rod slidably mounted in the cylindrical case, and a coil spring provided in the cylindrical case to outwardly urge the connecting rod so as to be contacted with the outside terminal at an end of the rod. A top end of the cylindrical case is contacted with the end of the lead.