JPS58219809A - Piezoelectric vibrator - Google Patents

Abstract

PURPOSE:To obtain a piezoelectric vibrator having effective impact resistance and easy to be fitted by extruding leading parts from both end parts of a sealing case. CONSTITUTION:Supporting springs 7, 8 are fixed on lead wires 5b, 6b of airtight terminals 5, 6, a crystal piece 2 on which driving electrodes 2a, 2b are formed is fixed between the supporting springs 7, 8, these parts are penetrated into a cylindrical member 4, and the airtight terminals 5, 6 are opposed at both end parts of the cylindrical member 4 and sealed. In case of fitting the crystal vibrator 1 on a printed board 9, the crystal oscillator 1 is dropped on a positioning hole 9a and the lead terminals 5b, 6b oppositely contacted with wiring patterns 9b, 9c and fixed by soldering or the like. Since the lead terminals 5b, 6b are projected at both terminal sides of the axial direction, these parts can be prepared by parts feeder similarly to other parts, so that the automatic assembling of the printed board can be easily attained.

Description

[Detailed description of the invention] The present invention relates to a piezoelectric vibrator.

Conventionally, a piezoelectric resonator such as a crystal resonator has been enclosed in a sealed container, and two lead terminals have generally been protruded in parallel from one side of the sealed container. When this crystal resonator was attached to a printed circuit board or the like, two lead terminals were inserted into a hole in the printed circuit board and fixed to the wiring pattern by soldering, making the installation extremely complicated. Furthermore, when automating the conventional mounting of a crystal resonator on a printed circuit board, preparations were required in order to perform automatic mounting after fixing the crystal-resonator to tape at predetermined intervals.

Further, in the conventional crystal resonator, due to the relationship between the position of the lead terminal and the holding spring of the crystal piece, the crystal piece sometimes hits the inner wall of the sealed container due to an impact, causing oscillation to stop.

The present invention eliminates the above-mentioned drawbacks, and provides a piezoelectric vibrator that is easy to attach to a printed circuit board, can be assembled using a normal parts feeder even when the attachment is automated, and is extremely resistant to impact. It is.

Examples of the present invention will be described in detail below.

In FIGS. 1 to 3, reference numeral "U" indicates a crystal resonator which is a piezoelectric resonator, and a crystal piece 2 which is a piezoelectric body is sealed in a sealed container 3. In this embodiment, the crystal blank 2 performs thickness-shear vibration, and both main surfaces are formed of curved surfaces, and driving electrodes 2α and 2b are provided on both main surfaces. The drive electrodes 2α, 2b extend in opposite directions to both ends. The sealed container 3 is composed of an outer cylindrical member 4 and airtight terminals 5 and 6 that close openings at both ends of the cylindrical member. In this embodiment, the cylindrical member 4 is made of a glass pipe, and the airtight terminals 5 and 6 are formed by sealing lead terminals 5b and 6b to both end members 5a and 6a made of glass. That is, the sealed container 3 is provided with lead terminals 5b and 6b at both ends in the axial direction.

The cylindrical member 4 and the airtight terminals 5 and 6 are sealed with low melting point glass or the like, and the inside of the sealed container 3 is kept airtight. 7 and 8 are holding springs that hold the crystal piece 2 in the sealed container 3.
Drive chamber #ii2a, 2b
and lead terminals 5b and 6b. The holding spring 7.8 is a spring material bent into a U-shape, and has a hole at one end into which the lead terminals 5b and 6b are press-fitted, and a support hole at the other end to support the crystal piece. It is. The crystal blank 2 and the lead terminals 5b and 6b are fixed to each other by solder, conductive adhesive, etc., and conduction is established.

In this way, the crystal resonator 1 includes lead terminals 5b, which are provided in the extending direction of the center line connecting the opposing support parts of the crystal piece 2;
6b, movement of the crystal piece 2 due to impact or the like is extremely small, and it almost never hits the inner wall of the sealed container 3. Since the cylindrical member of the sealed container 3 of this embodiment is made of glass, the frequency can be adjusted by appropriately removing the drive NfII7i2a, 2b of the crystal piece 2 with a laser beam.

To assemble the crystal resonator 1, one end of the holding spring 7.8 is fixed to the lead terminals 5b, 6b of the airtight terminals 5, 6 with solder or the like, and the crystal piece 2 is placed between the other ends of the holding spring 7.8. Support it and fix it with solder etc. After the airtight terminal 5, holding spring 7, crystal piece 2, holding spring 8, and airtight terminal 6 are fixed in succession in this way, they are passed through the inside of the cylindrical member 4, and the airtight terminals 5 are attached to both ends of the cylindrical member 4. , 6 to face each other.

Then, the cylindrical member 4 and the airtight terminals 5 and 6 are sealed in a vacuum or in a replacement gas atmosphere. This sealing is performed by directly heating and welding the glass cylindrical member 4 and the glass end members 5a, 6a, or by applying a low melting point glass paste and heating to seal them together.

To attach the crystal resonator 1 to a printed circuit board, a positioning hole 9a is made in the printed circuit board 9 as shown in the fourth figure.
The crystal resonator 1 is dropped into this positioning hole, and the lead terminals 5b and 6b are brought into contact with the wiring patterns 9b and 9c and fixed by soldering or the like. In this way, the crystal resonator 1 can be attached to the printed circuit board extremely easily. In addition, since the crystal resonator 1 is composed of a sealed container 3 in which lead terminals 5b and 6h protrude from both ends in the axial direction, when automatically assembling the printed circuit board, it can be aligned using a parts feeder like other parts. I can do it. Therefore, automatic assembly of printed circuit boards can be achieved extremely easily.

Next, another embodiment of the present invention will be described with reference to FIG. The crystal resonator is one in which a crystal piece 12 is sealed within a sealing field and a container 13. The crystal blank 12 has drive electrodes 12 (1,
126 is formed by vacuum deposition or the like. Sealed container 1
3 is a cylindrical member 14 on the outer periphery, airtight terminals 15 and 16 that close openings at both ends of the cylindrical member, and caps 156 at both ends.
, 16C. The cylindrical member 14 is a glass pipe, and has an airtight terminal 15. i6 is glass end member 1
Terminals 15b and 16b are sealed to 5a and 16a. The cylindrical member 14 and the airtight terminal 15.1/l are then sealed together in a vacuum or the like. Each of the terminals 15b and 16b has a groove formed on the inner end side, and the crystal piece 12 is fixed to this groove with solder or the like. The outer ends of the terminals 15b, j6b protrude from the airtight ends r-15, mA, and metal gaps '7' 15c, 16c are fixed thereto. For this reason, the drive electrode 12a is connected to the cap 15 through the terminal 15b. The drive voltage tII7i12b is connected to the cap 16c via the terminal 16b.

To assemble the crystal resonator opening, airtight terminals 1 are attached to both ends of the crystal piece 12.
5. After the grooves of the terminals 15b and 16b of 16 are engaged and fixed, they are passed through the inside of the cylindrical member 14, and both ends of the cylindrical member 14 and both end members 15α and 16α of the airtight terminals 15 and 16 are placed in a vacuum. Seal it with etc. After this, cap 1 on both ends
5c.

1/+c and secure it to the terminals 15b and 16b.

To attach the crystal oscillator to the printed circuit board, apply solder paste or the like to the wiring pattern of the printed circuit board, place the crystal oscillator opening on the solder paste, and then pass it through a furnace to fix it. good. It is also possible to make a positioning hole in the printed circuit board with a length slightly larger than the outer diameter of the sealed container 13 of the crystal resonator U and a width slightly smaller than the outer diameter so that it can be accessed.

Next, still another embodiment of the present invention will be described with reference to FIGS. 6 and 7. The crystal resonator 1 has a crystal piece 22 sealed in a container 23.
It is enclosed in. The crystal piece 22 has a driving electrode 22a.
, 226 are provided.

The sealed container 23 has openings at both ends of a metal cylindrical member 24.
Lead wires 25b to metal bases 25a and 26n,
26b is sealed with airtight glasses 25c and 26c, and airtight terminals 25 and 26 are sealed by means such as soldering or resistance welding. 27 and 28 are holding springs and lead wires 25b.

The crystal piece 22 is held and fixed to the drive electrode 22a,
22b and lead wires 25b and 26b, respectively. The lead wires 25b, 26b are formed with flat portions 25d, 26d, which are aligned with the main surface direction of the crystal piece 22. When the sealed container is made of glass 1i11 as in the above embodiment and the driving electrode is removed by a laser beam to adjust the oscillation frequency, the flat part 2
5d and 26d allow detection of the main surface of the crystal piece, making adjustment work easier.

The assembly of the crystal resonator is similar to the previous embodiment, with airtight terminals 25 and 26 attached to both ends of the crystal piece 22 via holding springs 27 and 28.
The lead wires 25b, 26b are fixed and passed through the inside of the cylindrical member 24, and the metal bases 25a, 26α and the cylindrical member 24 are sealed. The attachment of the crystal resonator to the printed circuit board is the same as in the first embodiment.

Note that although the crystal piece that performs thickness-shear vibration is shown, the present invention is not limited to this.

Further, although the sealed container is shown as having a cylindrical shape, it is of course possible to use a rectangular cylindrical shape.

As described in detail above, according to the present invention, the piezoelectric element sealed in the sealed container does not come into contact with the inner wall of the container due to impact, and a piezoelectric vibrator with excellent ftjgR properties can be provided. It is also easy to install on printed circuit boards.
Even in the case of automatic assembly, it has great effects such as being able to assemble the parts using a normal parts feeder.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of one embodiment of the present invention, Fig. 2 is a sectional view taken along the line It - I in Fig. 1, Fig. 5 is a partially cutaway plan view, Fig. 4 is an explanatory diagram of the installed state, and Fig. 5 is a sectional view of an embodiment of the present invention. The figure is a sectional view of another embodiment.
The figure is a sectional view of yet another embodiment, and FIG. 7 is a plan view thereof. 1.11.21...Crystal oscillator 2.12.22
...Crystal piece 3.13.23 ... Sealed container 4.14.24 ... Cylindrical member! 5. +5.15, 16, 25, 2 (S... Airtight terminal 5b, 6b, 15c, 16c, 25b, 26b...
...Lead Department and above Applicant Seikosha Co., Ltd. Agent Patent Attorney Mogami

Claims (1)

[Claims] 1. A cylindrical sealed container is provided with a driving electrode, and a piezoelectric body is sealed therein, and a lead portion connected to the driving electrode is provided at both ends of the sealed container in the axial direction. A piezoelectric vibrator characterized by being provided with. 2. A piezoelectric vibrator according to claim 1, wherein the sealed container includes a cylindrical member having openings at both ends and an airtight terminal that closes the openings at both ends. 3. The piezoelectric vibrator according to claim 1, wherein the lead portion is a lead wire and has a flat portion formed therein that coincides with the main surface direction of the piezoelectric body. 4. The piezoelectric vibrator according to claim 1, wherein the lead portion is a metal cap.