JPS6261171B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a crystal oscillator.

The crystal resonator in a conventional crystal oscillator is held at the upper end of a holding spring mounted on a circuit board and sealed with a cap.

However, holding the crystal resonator with a holding spring not only complicates the structure, but also requires time and effort to manufacture and assemble, resulting in high manufacturing costs.

The object of the present invention is to have a simple structure, easy to manufacture and assemble, and to be able to achieve thinness.
It is an object of the present invention to provide a crystal oscillator in which the crystal resonator can be easily mounted, the mounting strength is high, and a uniform conductive film can be easily formed.

Embodiments of the present invention will be described below based on the drawings.

Figures 1 to 3 show an example of a circuit unit in a crystal resonator, including a circuit board 1, a crystal resonator 2 placed and held on the upper surface of the circuit board, and a circuit board for sealing the crystal resonator. It consists of three caps.

First, the specific configuration of the circuit board 1 will be explained.

The substrate 4 of the circuit board is formed by injection molding a synthetic resin such as polysulfon. A mounting groove 5, which is a substantially ring-shaped cap mounting portion, is bored on one side of the board 4 (on the right side in Figures 5 and 6), and the open end of the cap 3 can be inserted into this mounting groove. be. Further, as shown in FIGS. 4 and 5, the mounting groove 5 is provided with pattern extension portions 6 and 7 at locations (two locations in the illustrated example) on the left side of the mounting groove 5, extending across the groove. This drawer portion is provided with inclined surfaces 6a and 7a which are inclined outwardly on the upper surface.

Also, the support surface 4 on the substrate 4 surrounded by the mounting groove 5
An auxiliary protrusion 8 is bored in the center part a, and a pair of mounting tables 9 and 10 facing each other with the auxiliary protrusion 8 in between are each integrally provided. As shown in FIGS. 4 to 6, the mounting tables 9 and 10 have rectangular upper surfaces, and rectangular inclined guide surfaces 9a and 10a extend from one side (left side) of the support surfaces 4a.
It has reached this point. Further, as shown in FIGS. 3 to 6, support protrusions 11 and 12 are provided on the support surface 4a and protrude from the outside of the mounting tables 9 and 10, respectively, so as to face each other. Each of the support protrusions 11 and 12 has a presser portion 11a and 12a at its upper end that extends inwardly (above the mounting table) in a tapered manner.
a, 12a, and presser parts 11a, 12a.
The outer peripheral portion of the crystal resonator 2 can be inserted between the mounting tables 9 and 10. Further, the outer surfaces of the support protrusions 11 and 12, which will be the conductive pattern forming portions, are the inclined surfaces 11 and 12.
b, 12b. 4b and 4c (third
(Illustrated) is a punch hole. 4d and 4e are protrusions for positioning the mask when forming a conductive pattern.

Furthermore, an IC mounting recess 13 is formed on the other side of the board 4 as shown in Figures 1, 2, 5, and 6.
Sides of IC mounting recess (two adjacent sides in the example shown)
There are continuous inclined surfaces 14 and 15 that are inclined outwardly and upwardly.

As shown in FIGS. 1, 3 and 4, a predetermined conductive pattern 16 is formed on the upper surface of the substrate 4 by vacuum deposition or a combination of sputtering and masking. Conductive patterns 17 and 1
8 are formed parallel to each other, and one side of each is connected to the support surface 4a through the pattern extraction parts 6 and 7.
, and further the mounting tables 9 and 10 and the support protrusion 1
The upper surfaces of 1 and 12 are covered with pattern coatings 17a and 18a and 17b and 18b that connect them. In this example, as shown in FIG. 3, the patterned coating 17a on the upper surface of one of the mounting tables 9 and the patterned coating 18b of the presser portion 12a of one of the support protrusions 12 constitute a terminal portion for the crystal resonator. The other side of the conductive pattern 17 is electrically connected to another conductive pattern 19 as shown in FIG. The other end of the conductive pattern 18 extends from the inclined surface 15 to the inner bottom surface of the IC mounting recess 13, forming a land 18c for die bonding of the IC. Conductive pattern 2
0 is located on the inclined surface 14.

Further, to explain the crystal resonator 2, the outer peripheral part of this crystal resonator is placed on the upper surface of the mounting tables 9 and 10 as shown in FIGS.
a and is fixed with a conductive adhesive 21. Among the electrode films 22 and 23 formed on the upper and lower surfaces of the crystal resonator 2, the lead electrode 22a of one electrode film 22 is connected to the terminal portion 18b of the conductive pattern 18 on the support protrusion 12, and the lead electrode 23a of the other electrode film 22
is the terminal portion 17a of the conductive pattern 17 on the mounting table 9.
and are electrically connected by conductive adhesive 21, respectively.

Further, the cap 3 is made of a non-conductive material such as a synthetic resin such as polysulfon. The lower end opening of the cap 3 is fitted into the mounting groove 5 as shown in Figs. 1 to 3, and adhesive is applied to the fitted part to fix it.
Maintains airtightness. In this embodiment, a metal coating 24 is formed on the inner surface of the cap 3 as shown in FIGS. 2, 3, and 4, and the metal coating 24 prevents the oscillation frequency of the crystal resonator 2 from changing due to stray capacitance. It is intended to do so. Note that metal coating 2
The metal coating is formed only up to a certain position from the open end surface of the cap 3 so that the conductive patterns 17 and 18 are not electrically connected by the cap 3.

The shape of the cap mounting portion is not limited to the above example, and a circular mounting protrusion, for example, may be provided integrally on the base plate, and a mounting groove may be formed in the lower end opening of the cap to fit the two together. In this case, the mounting protrusion is provided with a pattern extension portion having a tapered or trapezoidal cross-sectional shape due to an inclined surface.

As mentioned above, there are places on the substrate that are higher than the substrate surface such as the mounting tables 9 and 10 and the support protrusions 11 and 12,
There are places that are lower than the board surface, such as the pattern pull-out parts 6 and 7 of the mounting groove 5 and the IC mounting recess 13.
A conductive pattern is formed by communicating the upper surfaces of these. In the case of the present invention, there is no stage between them, and the inclined surfaces 9a, 10a, 11a, 11b, 12
By forming conductive patterns a, 12b, 6a, 7a, 14, 15, etc., conductive patterns on surfaces having different heights are continuous across the sloped surface. When forming a conductive pattern using methods such as sputtering,
When there are steps, it is difficult to form a conductive film on the vertical surfaces thereof, and this causes unevenness in the conductive pattern, making it extremely difficult to form the entire conductive pattern uniformly. However, in the structure of the present invention, which has no steps and has a continuous sloped surface, it is extremely easy to uniformly form a conductive film.

Next, assembly will be explained.

First, the crystal resonator 2 is placed on the center left side of the substrate 4 with its flat surface facing down. Next, crystal oscillator 2
As the transducer is slid to the right, the upper and lower outer circumferential parts of the transducer slide on the inclined guide surfaces 9a and 10a of the mounting tables 9 and 10, and when they finish passing through the inclined guide surfaces, the upper and lower outer peripheral parts of the transducer slide on the upper and lower surfaces of the mounting table. and the holding parts 11a, 1 of the support protrusions 11, 12.
2a. The crystal oscillator is the first
When the third
As shown in the figure, use the conductive adhesive 2 using the punch hole 4b.
1, electrically connects the extraction electrode 23a of the electrode film 23 on the lower surface of the crystal resonator and the terminal portion 17a of the conductive pattern on the upper surface of the mounting table 9, and fixes the resonator. Further, the terminal portion 18b of the conductive pattern on the upper surface of the holding portion 12a and the lead electrode 22a of the electrode film 22 on the upper surface of the crystal resonator are bonded using a conductive adhesive 21.
to electrically connect and fix the vibrator. In addition, on the extraction electrode 23a side, the upper surface of the vibrator facing it is fixed with a conductive adhesive, and on the extraction electrode 22a side, the lower surface of the vibrator facing it is made conductive using the punch hole 4c. The crystal resonator may be more stably fixed by fixing with an adhesive.

In addition, the crystal resonator 2 is mounted on the mounting tables 9, 10 and the holding part 1.
1a and 12a, if the vibrator shifts to one side and one of its outer peripheral parts comes off the mounting table, the vibrator is received by the auxiliary protrusion 8 without falling any further. It becomes easy to return the detached outer peripheral portion to the original mounting table.

Thereafter, the lower end of the cap 3 is fitted into the mounting groove 5 to attach the cap. At this time, apply adhesive to the part where the cap is inserted, if necessary. Finally, the punch holes 4b and 4c are sealed with an appropriate member.

As described above, according to the present invention, the crystal resonator slides on the inclined guide surface of the mounting table and reaches the supporting position between the mounting table and the holding part, so installation is extremely easy and the crystal unit is integrated with the substrate. The mounting strength is high because it is mounted and supported on a standard mounting table, and since the mounting table and support stand are integrally formed with the board, the structure is simple, the number of parts is small, and manufacturing is easy. It is easy to use, thin and takes up little space, and can reduce costs. Furthermore, since the conductive pattern is continuous to surfaces with different heights through the inclined surface, a uniform pattern can be easily formed. Furthermore, since a metal film is formed on the cap, there is an effect that the oscillation frequency of the crystal resonator does not change due to stray capacitance.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a partially cutaway front view with the metal coating of the cap omitted, and FIG. 2 is a sectional view taken along the line of FIG. 1. 3 is an enlarged cross-sectional view taken along the lines of FIG. 2, FIG. 4 is an enlarged cross-sectional view taken along the lines of FIG. 1, and FIG. FIG. 6 is a sectional view taken along the line of FIG. DESCRIPTION OF SYMBOLS 1... Circuit board, 2... Crystal resonator, 3... Cap, 4... Board, 4a... Support surface, 5... Cap attachment part, 6, 7... Pattern drawer part,
6a, 7a, 11b, 12b...slanted surface, 9, 1
0...Placement table, 9a, 10a...Slope guide surface, 1
1, 12... Support protrusion, 11a, 12a... Pressing part, 16, 17, 18... Conductive pattern, 21...
... Conductive adhesive, 22, 23 ... Electrode film, 22
a, 23a...Extraction electrode, 24...Metal coating.

Claims (1)

[Scope of Claims] 1. A cap mounting portion provided on the upper surface of a synthetic resin substrate; a plurality of crystal resonator mounting stands integrally formed on the support surface of the substrate surrounded by the mounting portion; an inclined guide surface provided on the mounting table; a support protrusion integrally formed on the support surface and having a vibrator holding part extending upwardly from the mounting table; and a support protrusion provided on the upper surface of the substrate and described above A conductive pattern is provided with a terminal section for the crystal resonator on the mounting base and the support protrusion, a pattern pull-out section is provided across the cap mounting section, and the conductive pattern is inserted between the mounting base and the holding section, a crystal resonator electrically connected and fixed to the terminal portion with a conductive adhesive; and a non-conductive cap whose lower end is joined to the mounting portion to seal the crystal resonator. A crystal oscillator consisting of 2. A crystal oscillator according to claim 1, characterized in that a conductive pattern forming portion and a pattern extraction portion of the support protrusion are formed with inclined surfaces. 3. A crystal oscillator according to claim 1, characterized in that a metal coating is formed on the inner or outer surface of the cap.