JP3309333B2 - Quartz crystal support structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a support structure for a quartz oscillator.

[0002]

2. Description of the Related Art With the spread of surface mounting technology, quartz resonators are required to be compatible with surface mounting. At the same time, it is required to be thin. For this reason, a structure has been proposed in which the quartz-crystal vibrating piece is directly fixed to a container or a circuit board without using a supporting member. Generally, a rectangular thickness-sliding vibrator employs a structure in which the quartz vibrating piece is fixed at both ends in the longitudinal direction as disclosed in Japanese Utility Model Publication No. 61-17624. (See Fig. 7)

In the case where the substrate or the container is made of ceramics, if both ends are fixed, there is a change in frequency characteristics due to a change in temperature and a defect that the adhesive or the quartz vibrating piece is cracked. It has become. FIG.
FIG. 1 is a perspective view of a quartz-crystal vibrating reed 1 according to the present invention in which electrodes 2 are formed. The rectangular quartz-crystal vibrating reed has inclined parts at both ends in the longitudinal direction and is formed thinner at both ends than at the center.
The shape usually includes a convex type and a bevel type.
The electrode 2 has the same shape on both sides, and the electrode extending from the center to the end extends from the end to the back.

FIG. 2 is a cross-sectional view of the ceramic vibrating reed 1 mounted on a ceramic container 3 having a concave portion 4 formed in the center and fixed with an adhesive 6, for illustrating the present invention. The placed crystal vibrating piece 1 is fixed at its ends with an adhesive 6 at two places where electrodes are provided. The adhesive is conductive and fixes the quartz-crystal vibrating piece as well as electrically connects the electrodes 2 and 2 ′ with the electrode 5 formed on the container 3. FIG. 3 is a sectional view in which a lid 7 is further placed on the upper part of the container 3. The gap H2 between the upper surface of the crystal resonator element and the lower surface of the lid is 3 in order to make the crystal resonator thinner.
It is set to be less than 00 microns.

[Problems to be solved by the invention]

In FIG. 2, the adhesive 6 adheres to the upper surface of the quartz-crystal vibrating piece from the end to the length L1. As a guide, the adhesive 6 is located above the corner 3a of the concave portion 4 of the container. If the adhesive adheres to the center too much, it will adversely affect the vibration characteristics of the crystal vibrating piece, but if it is too small, the adhesive strength will be insufficient. The adhesive is a thermosetting resin and shrinks after curing. Since the quartz-crystal vibrating piece has an inclined portion, the quartz-crystal vibrating piece rotates around the support portion 3a, which is the corner of the container, as a fulcrum, and the opposite end of the quartz-crystal vibrating piece rises. FIG. 4 is a side sectional view for explaining the state. Lifting amount is H
1 is represented.

When H1 exceeds H2 (strictly, slightly differently), the upper surface of the crystal vibrating piece contacts the lower surface of the lid, resulting in a failure. Since the amount of lifting varies depending on the inclination or curvature of the inclined portion of the crystal vibrating piece, and the crystal piece is lifted depending on the curing conditions of the adhesive, it is necessary to increase the internal space of the lid, which makes thinning difficult.

In a crystal oscillator supporting structure in which a quartz vibrating piece having an inclined surface portion with respect to a longitudinal main surface of a thickness sliding vibrating piece having a substantially rectangular planar shape is fixed at one end in the longitudinal direction, a quartz vibrating piece is provided in a container. Two or more step portions are formed to support the inclined surface portion of the quartz vibrating piece so as to be adapted to the inclined surface portion of the piece;
The inclined portion of the lower surface of the crystal vibrating piece is supported by a supporting portion with a step portion of a point or more, and a gap between the crystal vibrating piece and the supporting portion located at the extreme end of the crystal vibrating piece among the plurality of supporting portions is further provided. A recess to be formed is provided.

[0008]

FIG. 5 is a partial sectional view for explaining a positional relationship between a support portion of a container and a quartz-crystal vibrating piece according to an embodiment of the present invention. The supporting portions of the crystal vibrating piece are 3a (first supporting portion) and 3b.
(2nd support part) It is an Example of two places. In the figure, h1 indicates that the inclined portion of the quartz-crystal vibrating piece moves from the first support portion 3a to the second support portion 3a.
This is an amount that changes at L2 during b.

In this embodiment, the length of the quartz vibrating piece is 8.0 m.
m, the length of the concave portion is 6.6 mm, L1 is 0.7 mm,
L2 is 0.5 mm. The second from the end of the crystal vibrating piece 1
The distance between the support portions 3b was set to 0.2 mm because the curvature of the inclined portion at the extreme end greatly varies in machining the inclined portion.
The inclination and the curvature of the inclined portion of the quartz-crystal vibrating piece are shapes that vary depending on the thickness and length of the quartz-crystal vibrating piece, and L1 and h1 may be set in accordance with the respective dimensions. The support portion 3b may be a step portion as shown in FIG. 5, but may be a partial convex portion. It should be decided in consideration of container production, adhesive flow, ease of assembly, etc.

FIG. 6 is a sectional view of part A in FIG. 5 as viewed from the left side. A concave portion 3c for forming a gap with the quartz vibrating piece is provided near the adhesive application of the support portion 3b. This is to allow the adhesive to reach the lower surface of the crystal vibrating piece via the concave portion 3c, and can further prevent the crystal piece from lifting.

[0011]

Since the present invention is constructed as described above, the following effects can be obtained.

1. Since there are a plurality of support portions of the crystal vibrating piece corresponding to the slope portion of the crystal vibrating piece, the support portion at the outermost portion serves as a stopper, so that the tip of the crystal vibrating piece can be prevented from rising. 2. By applying the adhesive also to the back surface of the crystal blank, the adhesive strength can be improved and the lifting can be further reduced. The curing conditions are simplified by the effects of 3.1 and 2. Due to the effects of 4.1 and 2, H2 of the crystal unit can be reduced, and the thickness can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view of a crystal resonator element according to the present invention.

FIG. 2 is a cross-sectional view of a quartz oscillator for explaining the present invention.

FIG. 3 is a cross-sectional view of a quartz oscillator for explaining the present invention.

FIG. 4 is a cross-sectional view of a crystal unit for describing a problem of the present invention.

FIG. 5 is a partial sectional view of one embodiment of the present invention.

FIG. 6 is a partial sectional view of another embodiment of the present invention.

FIG. 7 is a partial cross-sectional view for explaining a conventional technique.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 crystal vibrating piece 2, 2 ′ electrode 3 container 3 a first support 3 b second support 3 c recess 4 recess 5 electrode 6 adhesive 7 lid

 ──────────────────────────────────────────────────続 き Continued on the front page Judge Kazuyuki Shimono Judge Yoshitaka Jita Judge Shinji Uematsu (56) References JP-A-6-132773 (JP, A) JP-A-3-171807 (JP, A) Kaihei 2-105710 (JP, A) JP-A-59-33322 (JP, U) JP-B-51-46383 (JP, B2)

Claims (1)

(57) [Claims] 1. A supporting structure for a crystal resonator, in which a quartz vibrating piece having an inclined surface with respect to a longitudinal main surface of a thickness shear vibrating piece having a substantially rectangular planar shape is adhered and fixed at one end in a longitudinal direction. Forms two or more steps that conform to the inclined part of the crystal resonator element and support the inclined surface of the crystal resonator element.
The support portion of the two or more steps supports the inclined surface portion of the lower surface of the crystal resonator element, and the support portion of the plurality of support portions located at the end of the crystal resonator element has a gap with the crystal resonator element. have a recess to form a thermosetting resin adhesive is water from the recess
A support structure for a crystal resonator, which is wrapped around the lower surface of a crystal resonator element.