KR890003772B1 - Piezo speaker - Google Patents

Abstract

The speaker having double vibrating plates improves the middle and bass range characteristics. Upper and lower vibrating plates (2,2') are attached to upper and lower sides of a piezo electric device and rims of vibrating plates are fixed on a frame (3) of solid material which restrains the sound generated by an active upper vibrating plate utilizing a lower passive vibrating plate vibrated by the upper vibrating plate when the upper vibrating plate is vibrated by the piezo electric device. The sound of high frequency generated by the piezo electric device is restrained by the frame to be a sound in a middle and bass range.

Description

Piezoelectric speaker

1 is a cross-sectional view of a piezoelectric speaker of the present invention.

* Explanation of symbols for main parts of the drawings

1: piezoelectric vibrating element 2, 2 ': diaphragm

3: frame

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric speaker using a piezoelectric vibrating element, and more particularly, to a piezoelectric speaker in which mid- and low-pitched characteristics are improved by attaching a diaphragm to upper and lower end surfaces of the piezoelectric vibrating element to have a double diaphragm structure.

Generally, a speaker is a device that reproduces a current signal as a voice signal, and a dynamic speaker having a wide sound band is most widely used. Such a speaker has a structure in which a voice coil is installed in a magnetic circuit composed of a magnet and an upper and lower plate. As a result, the structure itself is not only complicated, but the space occupied by components increases, thereby increasing production costs and limiting the miniaturization of the set. There was a problem that becomes very difficult.

Accordingly, in recent years, a piezoelectric spur using a piezoelectric vibrating element, which is a new material that causes mechanical vibration when voltage is applied, has been developed. However, such a piezoelectric speaker has excellent reproducibility characteristics in the metallic and high sound regions, which are unique in sound wave reproduction. Although it is effectively used as a simple high-definition speaker or a signal buzzer, there has been a problem that the piezoelectric vibrating element has a very limited function in reproducing the low- and mid-range characteristics with good listening feeling.

Therefore, the present invention solves the problems of the conventional piezoelectric speaker as described above, and has a double diaphragm structure by attaching vibrations to both upper and lower end surfaces of the piezoelectric vibrating element in order to have a wide sound range such as a dynamic speaker. And it is an object to provide a piezoelectric souper with improved bass characteristics.

Hereinafter, the configuration, operation, and effects of the present invention will be described in detail with reference to the accompanying drawings.

The upper and lower diaphragms 2 and 2 'are attached to the upper and lower surfaces of the piezoelectric vibrating element 1, and the upper and lower diaphragms 2 and 2' have a rigid frame rim. The upper diaphragm 2, which is respectively fixed to the lower end and actively vibrates when the diaphragm 2, 2 'vibrates due to the vibration of the piezoelectric vibrating element 1, is manually vibrated along the upper diaphragm 2. While the vibration sound of the lower diaphragm 2 'is reduced, each vibration plate 2, 2' is fixed to the frame 3 made of a solid material, and the vibration sound is further suppressed. It is designed to force high frequency to drop into low and middle frequency range.

4 is a cabinet, 5, 5 'is a sonic passage hole, 6 is a flange, and 7 is a grill.

According to the present invention, the upper and lower diaphragms 2 and 2 'are respectively attached to upper and lower end surfaces of the piezoelectric vibrating element 1, and the edges of the diaphragms 2 and 2' are attached to upper and lower ends of the frame 3, respectively. The upper and lower diaphragms 2 and 2 'themselves having a double structure brake the vibrations of the upper and lower diaphragms 2 and 2' by fixing them, respectively, so that the lower vibration And it is to have the mid-tone characteristics.

Referring to the operation in more detail based on the cross-sectional view of the present invention shown in Figure 1, the frame 3 is fixed to the edge of the diaphragm (2) (2 ') attached to the upper and lower end surfaces of the piezoelectric vibrating element (1) A sonic passage hole 5 is formed on the side of the bar, and the sonic passage hole 5 'is also formed in the flange portion 6 of the frame 3 connected to the cabinet 4, the piezoelectric vibrating element 1 When a signal current is applied to the piezoelectric vibrating element 1, the signal current is converted into sound waves while generating minute vibrations, and the regenerated sound waves are attached to upper and lower end surfaces of the piezoelectric vibrating element 1. The vibration sound of the upper diaphragm 2 is radiated to the outside through the grille 7 while the vibration sound of the lower diaphragm 2 'is transmitted through the sound wave passage hole of the frame 3. 5) and the space of the frame (3) and cabinet (4) and the acoustic path hole (5 ') of the flange (6) Is radiated to the front. Lower diaphragm 2 'in which the upper diaphragm 2, which vibrates actively when the diaphragm 2, 2' vibrates due to the vibration of the piezoelectric vibrating element 1, is manually vibrated according to the diaphragm 2; The vibration sound is suppressed, while the rigid frame 3 brakes the vibrations of the upper and lower diaphragms 2 and 2 ', thereby forcibly lowering the high frequency frequency of the piezoelectric vibrating element 1 to the low and medium frequency regions. It is possible to stabilize to the required frequency band and increase the sound reproducing efficiency by vibrating the two vibration plates.

As described above, the present invention has a wide sound width, such as a dynamic speaker, and the structure itself can easily reduce the production cost, and can also reduce the size of the set by simplifying the structure, and in particular, the diaphragm (2) (2 ') Because it can be formed in a flat type, there is an effect that can be converted to a variety of appearances as needed compared to the conventional speaker limited to round, oval, square.

Claims (1)

In a piezoelectric speaker using a piezoelectric vibrating element, the upper and lower diaphragms 2, 2 'are attached to the upper and lower surfaces of the piezoelectric vibrating element 1, and the upper and lower diaphragms 2, 2' are attached. The upper diaphragm 2 is fixed to the upper and lower edges of the frame 3 of the solid material, and vibrates actively when the diaphragm 2, 2 ′ is vibrated by the vibration of the piezoelectric vibrating element 1. While the vibration sound is suppressed by the lower vibration plate 2 'which is manually vibrated according to the upper vibration plate, the vibration plates 2 and 2 are fixed to the frame 3 made of a solid material, and thus the vibration sound is further increased. It is further suppressed, the piezoelectric speaker characterized in that it is possible to forcibly lower the high frequency by the piezoelectric vibrating element (1) to the low and amplified frequency region.

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