JPH0654315U - Piezoelectric vibrator - Google Patents

Abstract

(57) [Abstract] [Purpose] When a piezoelectric vibrator with a piezoelectric oscillator directly fixed to the base was dropped, the piezoelectric oscillator was chipped or broken, and the frequency was greatly changed. The present invention alleviates the impact on the piezoelectric oscillator, suppresses chipping, breakage, and frequency change of the piezoelectric oscillator, and reduces the thermal expansion difference between the piezoelectric oscillator and the insulating substrate to change the long-term aging. Try to keep the amount small. [Structure] An insulating substrate is provided between a base and a piezoelectric oscillating piece, and a central portion thereof is fixed to the base, or a step is provided on the insulating substrate to facilitate fixing to the base and the piezoelectric oscillating piece.
In addition, the thermal expansion coefficients of the piezoelectric oscillator and the insulating substrate are approximated to suppress the amount of aging change in frequency.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a structure for improving the impact resistance of a piezoelectric vibrator.

[0002]

[Prior art]

As shown in the plan view of FIG. 5, a conventional piezoelectric vibrator has a mount base 52 and a pillow 53 formed by printing or the like on an insulating base 51 made of ceramic or the like, and a conductive pattern (not shown) to the outside. ) Was also formed by printing or the like. The piezoelectric oscillation piece 54 has an electrode pattern 55 made of a metal such as Ag using a method such as vapor deposition. The piezoelectric oscillation piece 54 was placed on the mount base 52 and the pillow 53, and fixed with a conductive adhesive 56 or the like. After that, the frequency was adjusted in vacuum using Ag or the like, the lid 57 was covered, and airtight sealing was performed using a low melting point glass 58 or the like in an N ₂ atmosphere to form a piezoelectric vibrator 59.

FIG. 6 shows a top view of a conventional piezoelectric vibrator 59.

The piezoelectric oscillation piece 54 on which the electrode pattern 55 is formed is placed on the mount base 52 and the pillow 53, and is fixed to the mount base 52 by cantilever support with a conductive adhesive 56 or the like.

The pillow 53 is provided to create a gap between the base 51 and the piezoelectric oscillation piece 54.

[0006]

[Problems to be solved by the device]

 However, in the conventional technology, since the piezoelectric oscillator is directly fixed to the base, when the piezoelectric vibrator receives an impact such as a drop, the impact is directly transmitted from the base to the piezoelectric oscillator, so It was chipped or broken. Due to the lack, a frequency deviation of the piezoelectric oscillation piece occurred, and if it was broken, the oscillation of the piezoelectric oscillation piece naturally stopped, and there was a bad effect such as a defective piezoelectric vibrator. In addition, since the base and the piezoelectric oscillator are directly fixed, the difference in thermal expansion coefficient between the base and the piezoelectric oscillator adversely affected the aging, such as the frequency shifting over a long period of time.

[0007]

[Means for Solving the Problems]

 Therefore, the present invention solves such a drawback. When fixing the piezoelectric vibrator to the base, the central part of the insulating substrate is first fixed to the base, and the piezoelectric oscillation piece is fixed thereon.

2. It is characterized in that the piezoelectric oscillation piece is cantileveredly supported on the insulating substrate.

3. It is characterized in that the thermal expansion coefficient of the insulating substrate is approximated to that of the piezoelectric oscillator.

[0010] 4. It is characterized in that a step is provided on the insulating substrate.

[0011]

【Example】

 An embodiment of the present invention will be described with reference to the plan view of FIG.

A conductive pattern (not shown) was formed by printing or the like on an insulating base 1 made of ceramic or the like. The insulating substrate 2 having the electrode pattern 23 formed thereon is fixed to the base 1 with a conductive adhesive 4 or the like. When fixing the insulating substrate 2 to the base 1, it is better to fix the central portion of the insulating substrate 2, and if possible, it is preferable to fix it at the central portion within 1/3 of the longitudinal length of the insulating substrate 2. good. Next, the piezoelectric oscillation piece 5 provided with the electrode pattern 6 made of a metal such as Ag is fixed to the insulating substrate 2 with a conductive adhesive 7 or the like by vapor deposition or the like. After that, the frequency is adjusted in a vacuum using Ag or the like, the lid 8 is covered, and the piezoelectric vibrator 10 is hermetically sealed in the N ₂ atmosphere using the low melting point glass 9 or the like.

FIG. 2 is a plan view of another embodiment of the present invention, and FIG. 3 is a top view of a steaming surface. It is the same as the embodiment of FIG. 1 until the insulating substrate 2 having the electrode pattern 3 formed on the base 1 is fixed with the conductive adhesive 4. The piezoelectric oscillation piece 5 on which the electrode pattern 6 is formed is cantilevered and fixed to the insulating substrate 2 with a conductive adhesive 7 or the like. From the viewpoint of impact resistance, it is more advantageous to fix the piezoelectric oscillation piece 5 by supporting both ends as shown in FIG. 1, but the characteristics, temperature characteristics and aging property of the piezoelectric oscillation piece deteriorate. In particular, the cantilever support shown in FIG. 2 is more advantageous when it comes to aging characteristics of several PPM level. If the thermal expansion of the insulating substrate 2 is made similar to that of the piezoelectric oscillation piece 5 by using a crystal plate, glass or the like, the characteristics will be further improved, and the temperature characteristics and the aging characteristics will be significantly improved even in the case of supporting both ends. If aging is required, cantilever support can be used to improve the characteristics. If the thickness of the insulating substrate 2 is too thick, the impact resistance is lost. In order to receive and disperse the shock received by the base 1 at the central portion of the insulating substrate 2, some elasticity is required. However, if the thickness is too thin, the insulating substrate 2 itself will be destroyed, so the thickness is from 0.05 mm to 0. It is desirable to select between 18 mm.

When the length of the insulating substrate 2 in the longitudinal direction is increased, the impact resistance is improved, but the entire length of the piezoelectric vibrator 10 is also increased. Therefore, the length of the insulating substrate 2 is selected according to the length of the piezoelectric oscillation piece 5. Is required. It is necessary to make a gap when fixing the base 1 and the insulating substrate 2 with the conductive adhesive 4. If there is no clearance, it is the same as when it is fixed directly to the base 1, so there is no point in providing the insulating substrate 2.

FIG. 4 is a plan view showing another embodiment of the present invention. The stepped insulating substrate 12 having the electrode pattern 11 formed on the base 1 is fixed with a conductive adhesive 4 or the like. Since the stepped portion having a length within 1/3 of the longitudinal direction is provided on the bottom of the insulating substrate 12, there is no need to make a gap when fixing with the conductive adhesive 4 or the like, and the treatment can be easily performed. The piezoelectric oscillation piece 5 on which the electrode pattern 6 is formed is cantilevered and fixed to the insulating substrate 12 with a conductive adhesive 7 or the like. The insulating substrate 12 is provided with a step by raising both ends so as to have a space in the vibrating main electrode portion (central portion) of the piezoelectric oscillating piece 5. By providing a step difference on the bottom surface and the top surface of the insulating substrate 12, the fixing to the base 1 and the piezoelectric oscillating piece 5 become very easy, and the dimension becomes stable.

[0016]

[Effect of device]

 The present invention sandwiches an insulating substrate between when fixing a piezoelectric oscillator to the base, and approximates the coefficient of thermal expansion of the insulating substrate to that of the piezoelectric oscillator, provides a step, and fixes the piezoelectric oscillator on a cantilever. And As a result, when a shock is applied to the piezoelectric vibrator, the insulating substrate first absorbs the shock force so that it is transmitted to the piezoelectric oscillator, so it is possible to prevent the piezoelectric oscillator from breaking or chipping, and suppressing frequency stoppage and frequency shift. Have an effect.

Further, by approximating the thermal expansion coefficients of the insulating substrate and the piezoelectric oscillation piece, the strain at the time of fixing the piezoelectric oscillation piece can be reduced, the influence of shock is reduced, and the frequency over a long period of time is reduced. It has an effect on shift aging.

[Brief description of drawings]

FIG. 1 is a plan view of an embodiment of the present invention.

FIG. 2 is a plan view of another embodiment of the present invention.

FIG. 3 is a top view of another embodiment of the present invention.

FIG. 4 is a plan view of another embodiment of the present invention.

FIG. 5 is a plan view of a conventional piezoelectric vibrator.

FIG. 6 is a top view of a conventional piezoelectric vibrator.

[Explanation of symbols]

 1 ... Base 2 ... Insulating substrate 3 ... Electrode pattern 4 ... Conductive adhesive 5 ... Piezoelectric oscillation piece 6 ... Electrode pattern 7 ... Conductive adhesive 8 ... Lid 9 ... Low melting point glass 10・ Piezoelectric vibrator 11 ・ Electrode pattern 12 ・ Insulating substrate 51 ・ Base 52 ・ Mount base 53 ・ Pillow 54 ・ Piezoelectric oscillation piece 55 ・ Electrode pattern 56 ・ Conductive adhesive 57 ・ Lid 58 ・ Low melting point glass 59 ・ Piezoelectric vibrator

Claims (4)

[Scope of utility model registration request] 1. When fixing a piezoelectric vibrator to a base, the central portion of an insulating substrate is first fixed to the base, and the piezoelectric oscillation piece is fixed on the central portion of the piezoelectric vibrator. 2. The piezoelectric vibrator according to claim 1, wherein the piezoelectric oscillation piece on the insulating substrate is cantilevered. 3. The piezoelectric vibrator according to claim 1, wherein the thermal expansion coefficient of the insulating substrate is approximated to the thermal expansion coefficient of the piezoelectric oscillation piece. 4. The piezoelectric vibrator according to claim 1, wherein a step is provided on the insulating substrate.