JP2009168845A - Piezoelectric buzzer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent variations in position of a tip of a lead spring to be connected to a piezoelectric vibration plate even if the variations occur when force-fitting the lead spring into a holding part of a terminal. <P>SOLUTION: Three fixing positions R1-R3 of a lead spring 5 are arranged on a line L1. Thus, the fixing position R3 to be a connection part 9 rotates only in the same position even if it rotates centering on the line L1, so that variations in height can be prevented. Also, three fixing positions R4-R6 of a lead spring 6 are arranged on a line L2. Thus, the fixing position R6 to be a connection part 10 rotates only in the same position even if it rotates centering on the line L2, so that the variations in height can be prevented. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a piezoelectric buzzer that electrically connects a piezoelectric diaphragm and a lead spring fixed to a terminal, and applies an AC voltage to the piezoelectric diaphragm through the lead spring to cause the piezoelectric diaphragm to ring.

Conventionally, as this type of piezoelectric buzzer, there are those described in Patent Documents 1 and 2, for example. In the piezoelectric buzzer described in these Patent Documents 1 and 2, one end of a lead spring corresponding to an external terminal is press-fitted into a slit (press-fit groove) of two holding parts formed by bending the end of the terminal, and the lead The lead spring is fixed by soldering the other end of the spring to the piezoelectric diaphragm.
JP 2007-256329 A JP 2007-256331 A

  However, in the piezoelectric buzzer described in Patent Documents 1 and 2, variation occurs when the lead spring is press-fitted into the slits of the two holding portions formed in the terminal. The problem of variation occurs.

  4A and 4B are schematic views showing this phenomenon. FIG. 4A is a perspective view of the holding portion of the lead spring and the terminal, and FIG. 4B is a side view showing a state where the press-fitting variation occurs. is there. As shown in these figures, the lead spring J1 rotates about the straight line L connecting the press-fitting locations of the two clamping portions J2 and J3, and the tip connection location J4 of the lead spring J1 is higher than the desired height. It becomes too high and floats, and on the contrary, it becomes low and overload is applied to the piezoelectric diaphragm.

  In view of the above points, the present invention provides a piezoelectric buzzer capable of preventing the position of the tip of the lead spring connected to the piezoelectric diaphragm from varying even when variations occur when the lead spring is press-fitted into the holding portion of the terminal. The purpose is to provide.

  In order to achieve the above object, according to the first aspect of the present invention, the first lead spring (5) is fixed at the first terminal (3) at two fixing locations (R1, R2), and the metal plate ( 2a), the first lead spring (5) is fixed or contacted at one connection place (R3), and the first lead spring (5) is fixed at the first terminal (3). One connecting place (R3) for fixing the first lead spring (5) to the metal plate (2a) is arranged on the straight line (L1) connecting the fixing places (R1, R2), and the second terminal. In (4), the second lead spring (6) is fixed at two fixing locations (R4, R5), and the second lead spring (6) is connected to the conductive layer (2b) at one connecting location ( Fixed or in contact with R6) The second lead spring (6) with respect to the conductive layer (2b) on the straight line (L2) connecting the two fixing places (R4, R5) fixing the second lead spring (6) with the screw (4) ) Is fixed at one location (R6).

  In this way, the three fixing locations (R1, R2) and the connection location (R3) of the first lead spring (5) are arranged on the same straight line (L1). For this reason, even if the connection location (R3) that becomes the connection portion (9) to be soldered or contacted to the metal plate (2b) is rotated about the straight line (L1), it is only rotating at the same location, Since the height can be prevented from varying, the position of the end portion (5a) that becomes the connecting portion (9) soldered or contacted to the piezoelectric diaphragm (2) of the first lead spring (5) does not vary. You can In addition, regarding the second lead spring (6), the three fixing places (R4, R5) and the connecting place (R6) are arranged on the same straight line (L2), so that the same as the first lead spring (5). The effect is obtained.

  In this case, the first lead frame (5) and the metal plate (2a) with reference to the surface of the case (1) where the piezoelectric diaphragm (2) and the first and second terminals (3, 4) are disposed. The two connection locations (R3) and the two fixed locations (R1, R2) with the first terminal (3) are different in height from the second lead frame (6) and the conductive layer (2b). If the height of the one connection place (R6) with the second terminal (4) is different from the two fixed places (R4, R5) with the second terminal (4), as shown in claim 2, the first The two fixing locations (R1, R2) fixing the first lead spring (5) at the terminal (3) are set to different heights, and the second lead is set at the second terminal (4). Height of two fixing places (R4, R5) fixing the spring (6) It may be different in height.

  In the invention according to claim 3, the first lead spring (5) is connected from one of the two fixing locations (R1, R2) in the first terminal (3) to one connecting location (R3) in the metal plate (2a). The second lead spring (6) is bent from two fixed places (R4, R5) in the second terminal (4) to one connection place (R6) in the conductive layer (2b). ) Is characterized in that it is bent to the point.

  In this way, by bending the first lead spring (5) and the second lead spring (6), the first lead spring (5) and the second lead spring (6) can exhibit a spring function. Become.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a front view of the piezoelectric buzzer according to the present embodiment. 2 and 3 are a left side view and a right side view of the piezoelectric buzzer shown in FIG. 1, respectively. Hereinafter, the piezoelectric buzzer according to the present embodiment will be described with reference to these drawings.

  As shown in FIG. 1, the piezoelectric buzzer includes a case 1, a piezoelectric diaphragm 2, terminals 3 and 4, lead springs 5 and 6, and a resistor (resistor) 7.

  The case 1 is made of an insulating material such as resin, and has a rectangular parallelepiped shape. A piezoelectric diaphragm 2, terminals 3, 4, lead springs 5, 6 and a resistor 7 are arranged on the inner surface of the case 1. One end side of the case 1 is a connector terminal 8, and a part of the terminals 3 and 4 protrudes from the connector terminal 8 so that electrical connection with the outside can be performed. The case 1 is actually provided with a cover, and the cover covers the piezoelectric diaphragm 2, terminals 3 and 4, lead springs 5 and 6, and resistor 7. For ease of understanding, it is not shown in FIGS.

  The piezoelectric diaphragm 2 includes a metal plate 2a formed of a circular thin plate and a piezoelectric ceramic plate 2c formed of a circular thin plate that is slightly smaller than the metal plate 2a. The piezoelectric ceramic plate 2c has a circular conductive layer 2b obtained by firing silver paste on the front and back surfaces, and is electrically connected to the metal plate 2a via the conductive layer 2b on the back side. For this reason, an alternating voltage can be applied to the piezoelectric ceramic plate 2c through the conductive layer 2b on the front surface side, the conductive layer 2b on the back surface side, and the metal plate 2a. The piezoelectric diaphragm 2 is fixed to the case 1 by bonding the metal plate 2 a side to the inner surface of the case 1.

  The terminal 3 is press-fitted or insert-molded into the case 1, and one end is exposed from the connector terminal 8 as described above. A lead spring 5 and a register 7 are fixed to one end of the terminal 3 on the inner side of the case 1. The terminal 3 is basically composed of a single plate-shaped metal member. However, the terminal 3 has three pinching portions 3a to 3c that are bent at the inner end of the case 1 in a direction perpendicular to the surface of the plate-shaped metal member. The lead spring 5 is fixed by two of the holding portions 3a and 3b, and the register 7 is fixed by the remaining one of the holding portions 3c. Specifically, slits (press-fit grooves) 3d to 3f that are notched in the direction perpendicular to the surface of the plate-like metal member are formed at the centers of the sandwiching portions 3a to 3c, and lead springs are formed in the slits 3d and 3e. The lead spring 5 and the terminal 3 are fixed and electrically connected by press-fitting one end of the resistor 5, and the resistor 7 and the terminal 3 are fixed and electrically connected by press-fitting the terminal 7a of the register 7 into the slit 3f. A connection is being made.

  The direction in which the lead spring 5 is sandwiched with respect to the slit 3d of the sandwiching portion 3a and the direction in which the lead spring 5 is sandwiched with respect to the slit 3e of the sandwiching portion 3b are perpendicular. As a result, the lead spring 5 is difficult to rotate. The heights of the sandwiching portions 3a and 3d are set to be the same, but the heights of the positions where the lead spring 5 is fixed in the slits 3d and 3e (the heights of fixing locations R1 and R2 described later) are different. Is set to This reason will be described in detail later.

  On the other hand, the terminal 4 is also press-fitted or insert-molded into the case 1, and one end is exposed from the connector terminal 8. A lead spring 6 and a register 7 are fixed to one end of the terminal 4 on the inner side of the case 1. The terminal 4 is basically composed of a single plate-like metal member. However, the terminal 4 has three pinching portions 4a to 4c that are bent in a direction perpendicular to the surface of the plate-like metal member at one end on the inner side of the case 1. The lead spring 6 is fixed by two of the clamping parts 4a and 4b, and the register 7 is fixed by the remaining one clamping part 4c. Specifically, slits (press-fit grooves) 4d to 4f that are notched in the direction perpendicular to the surface of the plate-like metal member are formed at the centers of the sandwiching portions 4a to 4c, and lead springs are formed in the slits 4d and 4e. The lead spring 6 and the terminal 4 are fixed and electrically connected by press-fitting one end of the resistor 6, and the resistor 7 and the terminal 4 are fixed and electrically connected by press-fitting the terminal 7b of the resistor 7 into the slit 4f. A connection is being made.

  The direction in which the lead spring 6 is sandwiched with respect to the slit 4d of the sandwiching portion 4a and the direction in which the lead spring 6 is sandwiched with respect to the slit 4e of the sandwiching portion 4b are perpendicular. As a result, the lead spring 6 is difficult to rotate. The heights of the sandwiching portions 4a and 4d are set to be the same, but the heights of the positions where the lead spring 6 is fixed in the slits 4d and 4e (the heights of fixing locations R4 and R5 described later) are different. Is set to This reason will be described in detail later.

  The lead spring 5 is for electrically connecting the terminal 3 and the metal plate 2a. One end 5a side is connected to the terminal 3, and the other end 5b side is connected to the metal plate 2a. ing. Specifically, one end portion 5a of the lead spring 5 is press-fitted into the slits 3d and 3e of the holding portions 3a and 3b formed in the terminal 3 as described above, and the other end of the lead spring 5 is inserted. The part 5b is a connection part 9 soldered or brought into contact with the surface of the metal plate 2a, that is, the part of the metal plate 2a that is not covered with the piezoelectric ceramic plate 2c.

  The lead spring 5 is bent in various directions, so that it can be fixed to the terminal 3 and electrically connected to the metal plate 2a, while exhibiting a spring function. Specifically, the lead spring 5 is oriented in the vertical direction with respect to the sandwiching portion 3b by being bent at a substantially right angle after one end portion 5a is stretched in the perpendicular direction with respect to the sandwiching portion 3a. After the fixed portion R2 at the clamping part 3b is passed, it is bent obliquely upward to the right and then bent obliquely downward to reach the other end part 5b. The other end portion 5b is a connection portion 9 which is soldered or brought into contact. In such a structure, the lead spring 5 is bent in accordance with the direction of the slits 3d and 3e between the sandwiching portions 3b of the terminal 3, whereby the terminal 3 can be fixed. Moreover, since the lead spring 5 is bent in various directions from the place fixed by the clamping part 3b to the place fixed to the metal plate 2a, the spring function is exhibited and the metal The end 5b is led to an electrical connection location with the plate 2a.

  Here, the relationship between the fixed portions of the lead spring 5 will be described. As described above, the lead spring 5 is fixed at the three fixing locations R1, R2 and the connecting location R3, ie, the clamping portion 3a, the clamping portion 3b, and the connecting portion 9, but these three fixing locations R1, R2 are fixed. The connection place R3 is arranged on a straight line. This is to cope with variations that may occur when the lead spring 5 is press-fitted into the slit 3d of the clamping part 3a and the slit 3e of the clamping part 3b. In other words, if variation occurs when press-fitting, the lead spring 5 rotates about a straight line L1 connecting the fixed locations R1 and R2 of the sandwiching portions 3a and 3b. For this reason, the connection place R3 which is the connection portion 9 in the lead spring 5 is also rotated around the straight line L1.

  However, if the three fixed locations R1, R2 and the connection location R3 are arranged on a straight line as described above, the connection location R3 to be the connection portion 9 also exists on the straight line L1. Even if the connection location R3, which is the connection portion 9, is rotated about the straight line L1, it is only rotated at the same location and the height does not vary. For this reason, it is possible to prevent the connection location R3, which is the connection portion 9, from becoming higher than the desired height and floating, or conversely becoming lower and applying an overload to the piezoelectric diaphragm 2.

  Note that the straight line L1 here is three-dimensionally drawn in the x, y, z space when the horizontal direction in FIG. 1 is the x direction, the vertical direction is the y direction, and the vertical direction is the z direction. It is a straight line. Although there is a difference in height between the fixing location R1 of the clamping portion 3a and the connection location R3 that is the connection portion 9, the clamping portion 3b is positioned so that the fixing locations R1, R2 and the connection location R3 are positioned on the straight line L1. The height of the fixing location R2 is also correspondingly lower than the height of the fixing location R1 of the clamping part 3a.

  The lead spring 6 is for electrically connecting the terminal 4 and the conductive layer 2b on the surface side of the piezoelectric ceramic plate 2c. One end 6a is connected to the terminal 4 and the other end. 6b is connected to the conductive layer 2b. Specifically, one end portion 6a of the lead spring 6 is press-fitted into the slits 4d and 4e of the clamping portions 4a and 4b formed in the terminal 4 as described above, and the other end of the lead spring 6 is inserted. The part 6b is a connection part 10 soldered or brought into contact with the surface of the conductive layer 2b.

  The lead spring 6 has a structure capable of exerting a spring function while being fixed to the terminal 4 and being electrically connected to the conductive layer 2b by being bent in various directions. Specifically, the lead spring 6 is oriented in the vertical direction with respect to the sandwiching portion 4b by being bent at a substantially right angle after one end portion 6a is stretched in the perpendicular direction with respect to the sandwiching portion 4a. After being bent obliquely upward after exceeding the fixing place R5 in the sandwiching portion 4b, it is bent obliquely leftward and downward to reach the other end 6b. The other end portion 6b is a connection portion 10 that is soldered or brought into contact. In such a structure, the lead spring 6 is bent in accordance with the direction of the slits 4d and 4e between the sandwiching portions 4b of the terminal 4 so that the terminal 4 can be fixed. Further, since the lead spring 6 is bent in various directions from the place fixed by the clamping part 4b to the place fixed to the conductive layer 2b, the spring function is exhibited and the conductor The end 6b is led to an electrical connection location with the layer 2b.

  Here, the relationship between the fixed portions of the lead spring 6 will be described. As described above, the lead spring 6 is fixed at the three fixing locations R4, R5 and the connection location R6, ie, the clamping portion 4a, the clamping portion 4b, and the connection portion 10, but these three fixing locations R4 to R6. Are arranged on a straight line. This is to cope with variations that may occur when the lead spring 6 is press-fitted into the slit 4d of the clamping part 4a and the slit 4e of the clamping part 4b. That is, if variation occurs when press-fitting, the lead spring 6 rotates about the straight line L2 connecting the fixed locations R4, R5 of the both sandwiching portions 4a, 4b. For this reason, the connection place R6 which is the connection portion 10 in the lead spring 6 is also rotated about the straight line L2.

  However, if the three fixed locations R4, R5 and the connection location R6 are arranged on a straight line as described above, the connection location R6 that is the connection portion 10 also exists on the straight line L2. Even if the connection location R6 that is the connection portion 10 is rotated about the straight line L2, it is only rotated at the same location, and the height does not vary. For this reason, it is possible to prevent the connection location R6, which is the connection portion 10, from becoming higher than the desired height and floating, or conversely becoming lower and applying an overload to the piezoelectric diaphragm 2.

  Note that the straight line L2 here is also drawn three-dimensionally in the x, y, z space when the horizontal direction in FIG. 1 is the x direction, the vertical direction is the y direction, and the vertical direction is the z direction. It is a straight line. Although there is a difference in height between the fixing location R4 of the clamping portion 4a and the connection location R6, which is the connection portion 10, the clamping portion 4b is positioned so that the fixing locations R4, R5 and the connection location R6 are positioned on the straight line L2. The height of the fixing location R5 is also correspondingly lower than the height of the fixing location R4 of the clamping part 4a.

  As described above, in the piezoelectric buzzer according to the present embodiment, the three fixing locations R1 and R2 and the connection location R3 of the lead spring 5 are arranged on the straight line L1, that is, on the same straight line. For this reason, even if the connection location R3, which is the connection portion 9, is rotated about the straight line L1, it is possible to prevent the height from being varied only by rotating at the same location. 2, the position of the end portion 5a which is the connection portion 9 can be prevented from varying.

  Similarly, the three fixing locations R4, R5 and the connection location R6 of the lead spring 6 are arranged on the straight line L2, that is, on the same straight line. For this reason, even if the connection location R6, which is the connection portion 10, is rotated about the straight line L2, it can be prevented that the height varies by only rotating at the same location. 2, the position of the end portion 6a that is the connecting portion 10 can be prevented from varying.

  Therefore, it is possible to ensure the positional accuracy of the places where the connecting portions 9 and 10 are made, and it is possible to ensure the quality of the product.

(Other embodiments)
In the first embodiment, the lead springs 5 and 6 are bent so that the spring function can be exerted. However, the lead springs 5 and 6 are provided with coiled springs to exert the spring function. It is also possible. Even in this case, as described in the first embodiment, the three fixing locations R1 and R2 and the connection location R3 of the lead springs 5 and 6 and the fixing locations R4 and R5 and the connection location R6 are arranged on the same straight line. By doing so, the same effect as described above can be obtained.

It is a front view of the piezoelectric buzzer concerning a 1st embodiment of the present invention. It is a left view of the piezoelectric buzzer shown in FIG. It is a right view of the piezoelectric buzzer shown in FIG. It is the schematic diagram which showed a mode that dispersion | variation arises when a lead spring is press-fitted in the slit of two clamping parts formed in the terminal.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Case 2 Piezoelectric diaphragm 2a Metal plate 2b Conductive layer 2c Piezoelectric ceramic board 3 Terminal 3a-3c Clamping part 3d-3f Slit 4 Terminal 4a-4c Clamping part 4d-4f Slit 5, 6 Lead spring 7 Resistor 8 Connector terminal 9, 10 connection part L1, L2 straight line R1, R2 fixed place R3 connection place R4, R5 fixed place R6 connection place

Claims (3)

It has a metal plate (2a) and a piezoelectric ceramic plate (2c) provided with a conductive layer (2b) on the front and back surfaces, and through the conductive layer (2b) provided on the back surface of the piezoelectric ceramic plate (2c). The piezoelectric ceramic plate (2c) is bonded to the metal plate (2a) and the metal plate (2a) is exposed so as to protrude from the piezoelectric ceramic plate (2c) (2 )When,
A case (1) for accommodating the piezoelectric diaphragm (2) with the conductive layer (2b) on the surface side of the piezoelectric ceramic plate (2c) facing upward;
A first lead spring (5) electrically connected to the metal plate (2a);
A second lead spring (6) electrically connected to the conductive layer (2b) provided on the surface of the piezoelectric ceramic plate (2c);
A first terminal (3) fixed to the case (1), electrically connected to the first lead spring (5) and fixing the first lead spring (5);
A second terminal (4) fixed to the case (1), electrically connected to the second lead spring (6) and fixing the second lead spring (6);
The first lead spring (5) is fixed at two fixing locations (R1, R2) by the first terminal (3), and the first lead spring ( 5) is fixed or contacted at one connection location (R3), and the first lead spring (5) is fixed at the first terminal (3). The two fixing locations (R1, R2) The one connection place (R3) for fixing the first lead spring (5) to the metal plate (2a) is disposed on a straight line (L1) connecting the two,
The second lead spring (6) is fixed at two fixing locations (R4, R5) by the second terminal (4), and the second lead spring (2b) is fixed to the conductive layer (2b). 6) is fixed or contacted at one connection place (R6), and the second lead spring (6) is fixed at the second terminal (4). The two fixing places (R4, R5) The piezoelectric buzzer characterized in that the one connection place (R6) for fixing the second lead spring (6) to the conductive layer (2b) is arranged on a straight line (L2) connecting the two.   The first lead spring at the first terminal (3) with reference to the surface of the case (1) where the piezoelectric diaphragm (2) and the first and second terminals (3, 4) are disposed. The heights of the two fixing locations (R1, R2) fixing (5) are different from each other, and the second lead spring (6) is formed at the second terminal (4). 2. The piezoelectric buzzer according to claim 1, wherein heights of the two fixing places (R4, R5) fixing the two are different from each other. The first lead spring (5) extends from the two fixed locations (R1, R2) in the first terminal (3) to the one connection location (R3) in the metal plate (2a). Is bent,
The second lead spring (6) is bent from the two fixed places (R4, R5) in the second terminal (4) to the one connection place (R6) in the conductive layer (2b). The piezoelectric buzzer according to claim 1, wherein the piezoelectric buzzer is provided.

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