JPS589602B2 - Manufacturing method of piezoelectric ceramic vibrator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a piezoelectric ceramic vibrator using all types of vibration such as thickness vibration, radial vibration, spread vibration, and bending vibration, and particularly relates to a method for manufacturing a piezoelectric ceramic vibrator in an efficient and economical manner. The present invention relates to a method for manufacturing a piezoelectric ceramic vibrator that is small in size and has no fluctuation in characteristics.

Generally, for piezoelectric ceramic vibrators, it is essential to provide a space near the vibrating part so as not to impede the vibration.
Forming this space is difficult in terms of manufacturing.

Conventionally, as a manufacturing method that has made it easy to form this space, for example, as described in Japanese Patent Publication No. 45-22384, an electrode part provided on a piezoelectric ceramic plate is coated with a material such as wax. It has been proposed to form a space above the electrode portion by forming an insulating resin layer, and heating the resin layer during or after the formation to melt the film and absorb it into the insulating resin layer. ing.

However, in the piezoelectric ceramic vibrator manufactured by this manufacturing method, a space is formed only above the electrode part, and the peripheral part of the piezoelectric ceramic plate is fixedly supported by an insulating resin layer, making it difficult to store energy. It can only be used for piezoelectric ceramic vibrators, and cannot be used for non-energy confined type vibration modes such as thickness vibration, radial vibration, spread vibration, and bending vibration, which are the object of the present invention.

The present invention improves the conventional manufacturing method of energy-containing type piezoelectric ceramic vibrators, and provides a method that can be used for piezoelectric ceramic vibrators in all vibration modes, and is efficient, economical, and suitable for mass production. The purpose of the present invention is to provide a method for manufacturing a piezoelectric ceramic vibrator that is small and has excellent characteristics.

That is, in the present invention, when a piezoelectric ceramic substrate provided with electrodes, that is, a vibrating element, is supported by a terminal, by using a terminal having a larger outer diameter than the vibrating element, a sufficient amount of space-forming material is reliably applied to the entire vibrating element. It is designed to cover.

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a piezoelectric ceramic vibrating element, with electrodes 1b on both sides of a piezoelectric ceramic substrate 1a made of lead zirconate titanate, etc.
1c is formed.

2 and 3 are terminals, and as extracted and shown in FIG.

) has a larger external shape, and has protrusions 2a and 3 near the center.
a, cutouts 2b and 3b are provided on each side, and drawer portions 2c and 3c extend from one corner.

The vibrating element 1 is crimped and clamped between the terminals 2 and 3 so that the protrusions 2a and 3a of the terminals 2 and 3 coincide with the node point of the vibrating element 1 or its vicinity.

A porous thermosetting insulating resin layer 4 covers the entire vibrating element 1 with a space 5 in between, and fixes the peripheral edges of the terminals 2 and 3.

However, part of the notches 2b and 3b are excluded from the periphery, and in short, the insulating resin layer 4 is placed on the vibrating element 1 so that it does not adhere to the vibrating element 1 and suppressing the vibration of the vibrating element 1. It is sufficient to provide a space all around 1.

This insulating resin layer 4 is impregnated with a space forming material such as wax, paraffin, petrolatum, etc., as will be described in detail later.

FIG. 2 shows another embodiment.

10.11 is a terminal, and as extracted and shown in FIG. Hole iob. 1ib is formed.

A hole 10b, 1 is provided at or near the node point of the vibrating element 1.
The vibrating element 1 is held between terminals 10 and 11 so that the lbs match.

Then, solder 12,
At 13, the protrusions 10a, 11a are connected to the electrodes 1b, 1c, respectively.

In this way, terminals 10.
11 is fixed.

The other configurations are almost the same as the embodiment shown in FIG. 1, so the explanation thereof will be omitted.

FIG. 3 shows yet another embodiment.

On the electrodes 1b, Ic provided on the ceramic substrate 1a, convex portions 20, 21 are provided at or near the node points.
It is formed integrally with c.

The other configurations are almost the same as the embodiment shown in FIG. 2, so the explanation thereof will be omitted.

Next, various methods of manufacturing the piezoelectric ceramic vibrator described above will be explained.

For convenience of explanation, only the one shown in FIG. 3 will be described.

(1) In FIG. 4, a vibrating element 1 having electrodes 1b and 1c formed on both sides of a piezoelectric ceramic substrate 1a is sandwiched between terminals 10 and 11 that are integrally connected at the lower part.

At this time, it is the node point of the vibrating element 1 or a fixed point in the vicinity thereof.

The holes 10b and 1lb of the terminals 10 and 11 are aligned with the convex portions 20 and 21 of the electrodes 1b and 1c.

As shown in FIGS. 2 and 3, this terminal 10.11 has a larger outer shape than the vibrating element 1, and has notches 10c on each side.
11c is provided.

Then, solders 12 and 13 are poured into the holes 10b and 1lb to connect the protrusions 10a and 11a to the electrodes 1b and 1c, respectively.

At this time, the solder 12, 1
3 from flowing out to unnecessary parts on the electrodes 1b and Ic.

In this way, the terminals 10 are placed on the electrodes 1b and 1c, respectively.
, 11 are fixed.

The vibrating element 1 to which the terminals 10 and 11 are fixed is placed in a melt (or a solution may be used) of a space-forming material such as wax, vaseline, or paraffin.

Hereinafter, it will be referred to as molten liquid.

). In this way, terminals 10 and 11 questions and terminal 1
The first layer 30 is provided by attaching the space-forming material to the outer surfaces of the substrates 0 and 11 except for the peripheral edges thereof.

This single layer 30 reliably covers the entire periphery of the vibrating element 1 since the vibrating element 1 is located between the terminals 10 and 11 and is smaller than the outer diameter of the terminals 10 and 11.

Next, the vibration element 1 provided with the first layer 30 is immersed in a liquid made of porous thermosetting insulating resin such as phenolic or epoxy resin, and the second layer 31 is formed on the outside of the first layer 30. establish.

After drying, this second layer 31 is heated to form a first layer 30.
A material such as wax is liquefied or vaporized and absorbed into or released from the porous second layer 31 to form a space 32 in a portion of the first layer 30 .

At this time, the terminals io and i1 are provided with, for example, four cutouts so that material such as wax can be easily absorbed into the second layer or released to the outside thereof.

Therefore, the space 32 can be formed around the entire vibrating element 1, and the peripheral edges of the terminals 10 and 11 can be fixed with the second layer 31, so that vibrations can be suppressed regardless of the vibration state. Therefore, a desired piezoelectric ceramic vibrator can be obtained.

(2) In FIG. 4, the first layer 30 is provided by immersing it in a melt made of a space-forming material such as wax, paraffin, or petrolatum, which is viscous at room temperature.

According to this method, the entire periphery of the vibrating element 1 can be covered with the first layer 30 more reliably than in the first method described above.

Therefore, a sufficient space is secured for the vibration of the vibration element 1.

(3) Figure 5 shows the third manufacturing method, 40 is a container,
It has a substrate 41 with a large number of holes 41a therein, and a tube 42 at the bottom of which feeds air into the container 40.
is provided.

Powder of wax, paraffin, vaseline, etc. is placed on the substrate 41 within this container 40.

Air is then sent through the tube 42 to spread the powder 43.

Then, in the same manner as the first method shown in FIG.
After heating the vibrating element 1 provided with a temperature of 0.11 with a heater 44, it is placed in the diffusion powder 43.

Then, the powder 43 is melted and adhered to the entire vibrating element 1 to provide a first layer.

The process of providing the second layer and the process of forming the space are the same as those in the first method, so their explanation will be omitted.

(See Figure 4) (4) Figure 6 shows the fourth manufacturing method, 50 is a container,
A conduit 51 is provided with a spray nozzle 51a.

A space-forming material 52 such as wax, paraffin, or vaseline is placed in this container 50, and an air nozzle 53 is placed near the spray port 51a, and air is blown from the air nozzle 53 to the spray port 51a. The material 52 is sprayed in a mist form.

Then, in the same manner as the first method shown in FIG.
The vibrating element 1 provided with numbers 0 and 11 is placed in the atomizing material 52, and the material 52 is adhered to the entire vibrating element 1 to form a first layer.

The process of providing the second layer and the process of forming the space are the same as those in the first method, so their explanation will be omitted.

(See FIG. 4) The present invention is as described above, and can be used for any type of vibration configuration, and is extremely effective for efficient and economical mass production.

In particular, since a terminal having a larger external shape than the vibrating element is used, the space forming material can be reliably attached to the entire periphery of the vibrating element, that is, a space can be reliably provided around the entire periphery of the vibrating element.

Therefore, the vibration of the vibrating element is not inhibited by other members, and the original resonance characteristics of the vibrating element itself can be directly extracted as the output of the piezoelectric ceramic vibrator, resulting in excellent characteristics.

[Brief explanation of the drawing]

FIGS. 1 to 3 are views showing embodiments of the present invention, and FIGS. 4 to 6 are views showing a method for manufacturing a piezoelectric ceramic vibrator according to the present invention. 1 is a piezoelectric ceramic vibrating element, 2 and 3 are terminals, 4 is a porous thermosetting insulating resin layer, and 5 is a space.

Claims (1)

[Claims] 1. In a method for manufacturing a piezoelectric ceramic vibrator having a piezoelectric ceramic vibrating element and a terminal whose part comes into contact with a node point of the piezoelectric ceramic vibrating element or a fixed point in the vicinity thereof, a terminal having a larger outer diameter than the piezoelectric ceramic vibrating element Then, a space forming material such as wax, paraffin, petrolatum, etc. is applied to the entire piezoelectric ceramic vibration element, and a porous thermosetting insulating resin is applied to the entire piezoelectric ceramic vibration element except for a part of the terminal. , a piezoelectric ceramic vibrator in which the space-forming material is liquefied or vaporized by heat, absorbed by a porous thermosetting insulating resin, or released to the outside, and the entire piezoelectric vibrating element is coated with the hardened insulating resin through the space. manufacturing method.