CN205211407U - Piezoelectric type squealer - Google Patents

Abstract

The utility model relates to an electron squealer, it discloses a piezoelectric type squealer, includes: the casing, it includes less last cylinder of external diameter and the great lower cylinder of external diameter, upward the top of cylinder is opened and is had the vocal hole, the bottom of cylinder has not by confined installation face down, the inside of casing has the resonant cavity, wherein the resonant cavity communicates with each other with the external world through vocal hole and installation face, the piezoelectric patches, it is installed in the resonant cavity of casing through installation face, three wires are connected with B, F, the S tripolar electricity of piezoelectric patches respectively for to piezoelectric patches input audible signal. The utility model provides a slimming has been accomplished through redesign to piezoelectric type squealer product appearance, simultaneously, the size makes the acoustic pressure value of output can reach higher level through adjustment and optimization.

Description

A piezoelectric sounder

technical field

The present application relates to an electronic sounder, in particular to a piezoelectric sounder.

Background technique

Most of the traditional piezoelectric sounders are large in size and complicated in electrical connection, and cannot meet the thin requirements of new indoor alarms (such as smoke alarms, carbon monoxide alarms, and gas alarms, etc.). The patent with the publication number CN201054787 discloses an improved piezoelectric sounder. Compared with the traditional piezoelectric sounder, although its volume is smaller, there are still many problems, such as complicated electrical connections and poor vibration and sound effects. Wait.

Contents of the invention

In view of this, the present application provides a piezoelectric sounder to solve the above problems.

The piezoelectric sounder of the present application includes:

The housing includes an upper cylinder with a smaller outer diameter and a lower cylinder with a larger outer diameter, the top of the upper cylinder has a sound hole, and the bottom of the lower cylinder has an unclosed mounting surface; The interior of the housing has a resonant cavity, wherein the resonant cavity communicates with the outside world through the sound hole and the mounting surface;

The piezoelectric sheet is installed in the resonant cavity of the shell through the mounting surface;

The three wires are respectively electrically connected with the B, F, and S three poles of the piezoelectric sheet, and are used for inputting sounding signals to the piezoelectric sheet.

In one embodiment, there is a notch on the bottom edge of the lower cylinder for leading out the three wires.

In one embodiment, the three wires are fixed to the notch by dispensing glue.

In one embodiment, the piezoelectric sheet is fixed in the casing by silica gel.

In one embodiment, the outer diameter of the upper cylinder of the housing is 24-30 mm, and the height is 3-8 mm; the outer diameter of the lower cylinder is 37-43 mm, and the height is 3-8 mm; the height of the housing is 11-15 mm.

In one embodiment, the piezoelectric sheet is circular, and its diameter is larger than the inner diameter of the upper circular body, and its diameter is 25-42 mm.

In one embodiment, the outer diameter of the upper cylinder is 25 mm and the height is 6.3 mm; the outer diameter of the lower cylinder is 40 mm and the height is 6.5 mm.

In one embodiment, the sound emitting hole is circular with a diameter of 13 mm.

The beneficial effect of this application is:

According to the above-mentioned implementation of the piezoelectric sounder, the appearance of the product has been redesigned to achieve a thinner profile; at the same time, the size has been adjusted and optimized so that the output sound pressure value can reach a higher level;

The piezoelectric sounder implemented according to the above overcomes the disadvantage that the sound pressure increase is limited by the circular bottom cover in the patent with the publication number CN201054787, and at the same time saves materials and simplifies the structure;

The piezoelectric sounder implemented according to the above overcomes the disadvantages of complicated structure, high cost and difficult manufacture in the patent with the publication number CN201054787 due to the printed circuit board fixed on the circular bottom cover for switching. It directly fixes the three wires to the gap by dispensing glue, so that the vibration of the piezoelectric sheet will not be affected by the vibration of the wires.

Description of drawings

Fig. 1 is the structural representation of a kind of piezoelectric sounder in the prior art;

Fig. 2 is a schematic structural view of a piezoelectric sounder according to an embodiment of the present application;

Fig. 3 is an exploded view of a piezoelectric sounder according to an embodiment of the present application.

detailed description

The present application will be described in further detail below through specific embodiments in conjunction with the accompanying drawings.

As shown in Figure 1, the patent with the publication number CN201054787 discloses an improved piezoelectric sounder, including a housing 8, the housing 8 is formed by connecting a hollow upper cylinder 9 and a lower cylinder 10, and a sound emitting hole 16 Located on the top of the upper cylinder 9 , the housing opening is located on one end surface of the lower cylinder 10 , and the housing opening is closed by a circular bottom cover 14 . The piezoelectric sheet 11 is fixed in the casing 8 . The printed circuit board 13 is installed on the bottom cover 14, the piezoelectric film 11 is electrically connected with the printed circuit board 13 through three lead wires 12, and the printed circuit board 13 is connected with three output wires 15 and drawn out through the gap on the housing as product output. The driving circuit can drive the piezoelectric sheet 11 through three output wires 15 .

In actual work, the printed circuit board 13 acts as a switch to avoid the influence of the traditional lead wires connected to the piezoelectric sheet on the vibration of the piezoelectric sheet, thereby affecting the sounding effect of the piezoelectric sheet.

The bottom cover 14 is used to fix the printed circuit board 13, and cooperates with the printed circuit board 13 to complete the transition. However, it is found in actual work that the bottom cover 14 limits the increase in the sound pressure of the product.

Considering the various shortcomings of the traditional piezoelectric sounder, the present application proposes a piezoelectric sounder, as shown in Figure 2 and Figure 3, which includes a housing 20, a piezoelectric sheet 30 and three wires 40, specifically described below .

The housing 20 includes an upper cylinder 21 with a smaller outer diameter and a lower cylinder 23 with a larger outer diameter. In one embodiment, the casing 20 is integrally formed. The top of the upper cylinder 21 has a sound hole 22, and the bottom of the lower cylinder 23 has an unclosed mounting surface. The housing 20 has a resonant cavity inside, and the resonant cavity communicates with the outside through the sound emitting hole 22 and the mounting surface.

The piezoelectric sheet 30 is installed inwardly in the resonant cavity of the housing 20 through the mounting surface of the housing 20 . In one embodiment, the piezoelectric film 30 is fixed in the casing 20 by silicone.

The three wires 40 are electrically connected to the three poles B, F, and S of the piezoelectric film 30 respectively, and are used for inputting sounding signals to the piezoelectric film 30 . In one embodiment, the other ends of the three wires 40 are electrically connected to a circuit board 50 , and the circuit board 50 is used to drive the piezoelectric sheet 30 through the three wires 40 .

In order to prevent the vibration generated by the piezoelectric sheet 30 receiving the sound signal from being affected by the wires connected to it, in one embodiment, a notch 24 is opened on the bottom edge of the lower cylinder 23 of the housing 20, and the notch 24 is used to lead out the above-mentioned The three wires 40 are fixed to the notch 24 by dispensing glue.

The application also redesigns the size of the piezoelectric sounder, and further adjusts and optimizes it in actual tests, so that the output sound pressure value of the product can reach a very high level.

In one embodiment, the outer diameter of the upper cylinder 21 of the housing 20 is 24-30 mm, and the height is 3-8 mm; the outer diameter of the lower cylinder 23 is 37-43 mm, and the height is 3-8 mm; The overall height of the housing 20 is 11-15 mm. In accordance with the size of the housing 20, in one embodiment, the piezoelectric sheet 30 is circular with a diameter of 25-42 mm. The piezoelectric sounder of the above size improves the output sound pressure value of the alarm itself or the alarm using the piezoelectric sounder, which can meet the sound pressure requirements of the alarm in the European standard EN14604:2005 (full anechoic room, 3 meters, Greater than 85dB.

In another embodiment, the outer diameter of the upper cylinder 21 of the housing 20 is 25 mm and the height is 6.3 mm; the outer diameter of the lower cylinder 23 is 40 mm and the height is 6.5 mm. In accordance with this size, the sound emitting hole 22 is circular with a diameter of 13 mm. For the piezoelectric sounder of this size and the alarm using the piezoelectric sounder of this size, the electrical performance index and sound effect are the best in the size range in the previous paragraph.

The piezoelectric sounder of the present application does not have the product in Fig. 1 because the shell opening is closed by the circular bottom cover 14 like the product in Fig. 1 The disadvantage of enclosing this structure is that the sound pressure increase of the product is limited.

The piezoelectric sounder of the present application directly fixes the three wires 40 to the notch 24 of the housing 20 and draws them out, so that the vibration of the piezoelectric sheet 30 will not be affected by the vibration of the wires, so that it does not have to be like the product shown in Figure 1. The circuit printed board 13 is needed for switching, and it is not necessary to introduce the circuit printed board 13 like the product in Fig. 1, thereby introducing the bottom cover 14 for fixing it. It is simple, and does not need the circuit printed board 13 and the bottom cover 14, which greatly saves materials, reduces costs, and reduces manufacturing difficulty.

Finally, the appearance of the piezoelectric sounder of this application has been redesigned to be thinner; at the same time, the size has been adjusted and optimized so that the output sound pressure value can reach a higher level.

The above content is a further detailed description of the present application in conjunction with specific implementation modes, and it cannot be considered that the specific implementation of the present application is limited to these descriptions. For those of ordinary skill in the technical field to which the present application belongs, some simple deduction or replacement can also be made without departing from the inventive concept of the present application.

Claims (8)

1. A piezoelectric sounder, characterized in that, comprising: The housing includes an upper cylinder with a smaller outer diameter and a lower cylinder with a larger outer diameter, the top of the upper cylinder has a sound hole, and the bottom of the lower cylinder has an unclosed mounting surface; The interior of the housing has a resonant cavity, wherein the resonant cavity communicates with the outside world through the sound hole and the mounting surface; The piezoelectric sheet is installed in the resonant cavity of the shell through the mounting surface; The three wires are respectively electrically connected with the B, F, and S three poles of the piezoelectric sheet, and are used for inputting sounding signals to the piezoelectric sheet. 2. The piezoelectric sounder according to claim 1, wherein a notch is formed on the bottom edge of the lower cylinder for leading out the three wires. 3. The piezoelectric sounder according to claim 2, wherein the three wires are fixed to the notch by dispensing glue. 4 . The piezoelectric sounder according to claim 1 , wherein the piezoelectric sheet is fixed in the casing by silica gel. 5. The piezoelectric sounder according to any one of claims 1 to 4, wherein the outer diameter of the upper cylinder of the housing is 24-30 millimeters, and the height is 3-8 millimeters; The outer diameter of the cylinder is 37-43 mm, and the height is 3-8 mm; the height of the shell is 11-15 mm. 6. The piezoelectric sounder according to claim 5, wherein the piezoelectric sheet is circular, and its diameter is larger than the inner diameter of the upper circular body, and its diameter is 25-42 mm. 7. The piezoelectric sounder according to any one of claims 1 to 4, wherein the outer diameter of the upper cylinder is 25 millimeters, and the height is 6.3 millimeters; the outer diameter of the lower cylinder is 40 mm and a height of 6.5 mm. 8. The piezoelectric sounder as claimed in claim 7, wherein the sound emitting hole is circular with a diameter of 13 mm.