JPH04255104A - Manufacture of piezoelectric component - Google Patents

Abstract

PURPOSE:To obtain an excellent resonance characteristic by applying frequency adjustment ink only to a part of both sides of a piezoelectric resonance element opposite to each other, melting and removing wax coated to a vibration part of the element after coating the entire part with an outer packing resin and forming a vibration space. CONSTITUTION:Frequency adjustment ink 4 is applied only to a part 2a of a vibration electrode 2 opposite to each other on both sides of a piezoelectric resonance element 3 and wax 5 is applied to a vibration part of the element 3 including the coated part with the ink 4. The wax 5 is coated to the vibration part of the element 3. The entire part is coated by an insulating outer package resin 6 and the resin 6 is cured by heating and the wax 5 is molten and removed by allowing the molten wax to be absorbed by the resin 6. Thus, a distance A between the coated part by the resin 6 and an end of the part 2a is increased to form a sufficient vibration space 7 around the vibration part of the element 3. Thus, excess damping by the resin 6 is prevented to obtain an excellent resonance characteristic.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a piezoelectric component, and more particularly, to a method of manufacturing a piezoelectric component in which frequency is adjusted by applying frequency adjustment ink.

0002

[Prior Art] In the conventional manufacturing method of piezoelectric components,
As shown in FIGS. 5 and 6, frequency adjustment is performed by applying frequency adjustment ink 4 to substantially the entire surface of a piezoelectric resonant element 3, which is formed by providing vibrating electrodes 2 on both sides of a piezoelectric substrate 1. After applying wax 5 on this frequency adjustment ink 4 (FIG. 7), the entire piezoelectric resonant element 3 is covered with an insulating exterior resin 6 such as epoxy resin, and this is heated to a predetermined temperature. to harden the exterior resin 6,
By melting the wax 5 and absorbing it into the exterior resin 6, a vibration space 7 for the piezoelectric resonant element 3 is created inside the exterior resin 6.
(Figure 8).

0003

[Problems to be Solved by the Invention] However, in the above-mentioned conventional piezoelectric component manufacturing method, since the frequency adjustment ink 4 is coated on substantially the entire surface of the piezoelectric resonant element 3, it is difficult to blend in with the frequency adjustment ink 4. The wax 5 (with poor wettability) does not spread over the entire surface of the frequency adjustment ink, and when it is covered with the exterior resin 6 and the wax 5 is melted and removed, the plane area of the vibration space 7 that is formed is small. ,
The vibration space 7 is formed almost only in the opposing portion 2a (overlapping portion) of the vibrating electrodes 2,2. On the other hand, the vibrating part of the piezoelectric resonant element 3 is not limited to the opposing part 2a but also extends to some extent around the opposing part 2a. There is a problem in that the vibration of No. 3 is excessively damped by the exterior resin 6, and the resonance characteristics are deteriorated.

The present invention solves the above-mentioned problems, and is a piezoelectric device that can form a sufficient vibration space, prevent excessive damping due to the exterior resin, and ensure good resonance characteristics. The purpose is to provide a method for manufacturing parts.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the piezoelectric component manufacturing method of the present invention provides a piezoelectric component in which a piezoelectric resonant element formed by forming vibrating electrodes on both sides of a piezoelectric substrate is covered with an exterior resin. In the manufacturing method, a frequency adjustment ink is applied only to mutually opposing parts of the vibrating electrodes on both sides of the piezoelectric resonant element, and a vibrating part of the piezoelectric resonator including the part coated with the frequency adjustment ink is coated. After applying the wax, the entire body is covered with an exterior resin, which is heated to harden the exterior resin, and the wax is melted and removed to form a vibration space for the piezoelectric resonant element.

[0006]

[Operation] Since the frequency adjustment ink is applied only to the opposing parts of the vibrating electrodes on both sides of the piezoelectric resonant element, the wax applied around the opposing parts goes beyond the opposing parts and vibrates around it. When the outer periphery of the piezoelectric resonant element is covered with an outer resin, the opposing part of the piezoelectric resonant element and the vibrating parts around it are covered by the outer resin. prevent this from happening. Therefore, a sufficient vibration space is formed around the vibrating portion of the piezoelectric resonant element, preventing excessive damping by the exterior resin, and achieving good resonance characteristics.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 and 2, the piezoelectric resonant element 3 of the piezoelectric component of this embodiment is formed by providing vibrating electrodes 2 on both sides of a piezoelectric substrate 1, and the tip side of the vibrating electrode 2 is connected to the piezoelectric substrate 1. They face each other via 1. Then, frequency adjustment is performed by applying frequency adjustment ink 4 to the facing portion 2a of the vibrating electrode 2 so as not to protrude too much to the surrounding area. Then, wax 5 is applied on top of this frequency adjustment ink 4 and on the piezoelectric substrate 1 around it (Figure 3).
do. In this case, since the piezoelectric substrate 1 is more compatible with the wax 5 and has better wettability than the frequency adjustment ink 4, the wax 5 spreads to the vibrating portion around the opposing portion 2a. Thereafter, the entire piezoelectric resonant element 3 is covered with an insulating exterior resin 6 such as epoxy resin, heated to a predetermined temperature to harden the exterior resin 6, and the wax 5 is melted and absorbed into the exterior resin 6. A vibration space 7 is formed around the vibrating portion of the piezoelectric resonant element 3 (FIG. 4).

The piezoelectric component manufactured in this manner has a sufficient vibration space 7 formed around the vibrating part of the piezoelectric resonant element 3 (FIG. 4), and the part covered with the exterior resin 6 and the vibrating electrode. Since the distance A from the end of the opposing portion 2a of 2 is large, excessive damping due to the exterior resin 6 is suppressed, and good resonance characteristics are obtained.

As shown in FIGS. 1 to 4, although the frequency adjustment ink 4 slightly protrudes from the opposing portion 2a of the vibrating electrode 2, it is substantially applied to the opposing portion 2a. . In this specification, "applying frequency adjustment ink only to the opposing portion" strictly refers to the opposing portion 2a.
In addition to cases in which it is applied only to the area, as in the above example, cases in which it is applied almost to the opposing part 2a and slightly protrudes,
Alternatively, the concept also includes a case where the tip of the opposing portion is not slightly reached, and in any of these cases, substantially the same effect can be obtained.

[0010] In the present invention, the type of frequency adjustment ink is not particularly limited, as long as it is effective for mass damping, and various materials such as resist ink can be used.

[0011]

Effects of the Invention As described above, the piezoelectric component manufacturing method of the present invention applies frequency adjustment ink only to the opposing portions of the vibrating electrodes on the piezoelectric resonant element, and also applies the frequency adjustment ink to the portions to which the frequency adjustment ink is applied. After wax is applied to the vibrating part of the piezoelectric resonant element, including the It is possible to manufacture a piezoelectric component with excellent resonance characteristics without being excessively damped by the exterior resin.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one step of the piezoelectric component manufacturing method of the present invention.

FIG. 2 is a plan view showing one step of the piezoelectric component manufacturing method of the present invention.

FIG. 3 is a sectional view showing another step of the piezoelectric component manufacturing method of the present invention.

FIG. 4 is a cross-sectional view showing a piezoelectric component manufactured by the piezoelectric component manufacturing method of the present invention.

FIG. 5 is a cross-sectional view showing one step of a conventional piezoelectric component manufacturing method.

FIG. 6 is a plan view showing one step of a conventional piezoelectric component manufacturing method.

FIG. 7 is a cross-sectional view showing another step in the conventional piezoelectric component manufacturing method.

FIG. 8 is a cross-sectional view showing a piezoelectric component manufactured by a conventional piezoelectric component manufacturing method.

[Explanation of symbols]

Claims (1)

[Claims] 1. A method for manufacturing a piezoelectric component in which a piezoelectric resonant element formed by forming vibrating electrodes on both sides of a piezoelectric substrate is coated with an exterior resin, wherein only the mutually opposing portions of the vibrating electrodes on both sides of the piezoelectric resonant element are After applying frequency adjustment ink and wax to the vibrating part of the piezoelectric resonant element including the part coated with the frequency adjustment ink, the entire body is covered with an exterior resin, and this is heated to coat the exterior resin. A method of manufacturing a piezoelectric component, comprising curing the wax and melting and removing the wax to form a vibration space of a piezoelectric resonant element.