JPH0317460Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to the structure of a crystal resonator, particularly to the structure of a crystal resonator in which electrodes are provided on both sides of a plate-shaped crystal piece.

A crystal resonator in which electrodes are provided on both sides of a plate-shaped crystal piece is known as an AT cut crystal resonator, for example. The crystal resonator, as shown in FIG.
For example, circular or oval excitation electrodes 2 and 3 are provided on both sides of a crystal piece 1 cut out into a disc shape and polished into a flat plate shape, and from the excitation electrode 2, extending laterally, the crystal piece 1
A connecting conductor 2a reaching the edge of the excitation electrode 3 is provided.
A connecting conductor 3a is provided which extends laterally from the connecting conductor 3a and reaches the edge on the opposite side from the connecting conductor 2a. Then, clamp the connecting conductor 2a with the clip 5a provided at the tip of the lead wire 5 extending from the base 4, and
A clip 6 provided at the tip of the lead wire 6 extending from
Attach the connecting conductor 3a at points a, apply conductive adhesive to each connection point between the connecting conductor 2a and the clip 5a, and between the connecting conductor 3a and the clip 6a to ensure conductivity, and attach a crystal piece to the base. After it has been securely fixed mechanically, it is covered with a protective cap.

By the way, when attaching the crystal piece to the tip of the lead wire, the above-mentioned crystal resonator requires a lot of effort to assemble because it must be aligned so that the connecting conductor is at the position of the clip. Also,
If the crystal resonator has a square crystal piece, it is possible to automatically align one of the four sides to the reference position, so you can accurately position the crystal resonator and connect the lead wire or clip to the crystal piece. Although it is relatively easy to accurately position the connecting conductor of the quartz crystal unit, connect it electrically and mechanically, and assemble it automatically, in the case of a quartz crystal resonator with a circular crystal piece, it is difficult to locate the reference position like a square one. Since there is no such thing, precise positioning is not possible, and automatic assembly of the crystal resonator is therefore impossible.

A stray capacitance Co is present in the crystal resonator, which is formed by the capacitors formed by the excitation electrodes 2 and 3 and the connecting conductors 2a and 3a. The stray capacitance of multiple crystal oscillators used in assembling a crystal filter must be close to the design value of the filter, but in reality it is difficult to use a crystal oscillator with the required stray capacitance Co. It is difficult to obtain such a value, and currently a small capacitor for adjustment is added to the outside of the crystal oscillator when assembling the filter.

The present invention was made to improve the above-mentioned disadvantages, and its purpose is to connect two lead wires around a circular crystal piece with excitation electrodes on both sides. One lead wire is always connected to one excitation electrode, and the other lead wire is connected to the other excitation electrode, no matter which peripheral it comes into contact with, and the stray capacitance can be adjusted arbitrarily. The purpose is to provide a vibrator.

Next, one embodiment of the present invention will be described in detail using the drawings.

FIG. 2A shows the pattern of the conductive layer with the front side and the back side of the crystal resonator according to the present invention opened in the direction of the arrow, respectively, as shown in FIG. 2B. Similar to the conventional structure shown in FIG. 1, this crystal resonator has excitation electrodes 11 and 1 facing a circular crystal piece 10 on both sides 10a and 10b.
1' is provided, and later two lead wires to be connected to these excitation electrodes 11, 11' are provided at the peripheral edge of this crystal piece 10. That is,
An excitation electrode 11 is formed in the center of the front surface side 10a, and at the periphery of the crystal blank 10 surrounding this excitation electrode 11, a support electrode is formed, which is divided into four sections each having a length of about 1/4 of the circumference. 13a, 13
b, 13c, and 13d are partially releasably attached. Furthermore, these supporting electrodes 1
The extraction electrodes 12a, 12b, 12c, and 12d, which are extended in the radial direction from the excitation electrode 11 up to 3a, 13b, 13c, and 13d, are also removably attached. The extraction electrode 12a is connected to the support electrode 13a, the extraction electrode 12b is connected to the support electrode 13b, and the extraction electrode 12c is connected to the support electrode 1.
3c, and the extraction electrode 12d is connected to the support electrode 13.
connected to d. Back side 10b of crystal piece 10
An excitation electrode 11' is formed in the center. Four extraction electrodes 12a', 12b', 12c', and 12d' are formed in the radial direction from the periphery of the excitation electrode 11'. Support electrodes 13a', 13b', 13c', and 13d' are formed on the periphery of the back side 10b of the crystal piece 10, each having a length of approximately 1/4 of the circumference and separated from each other. The extraction electrode 12a' is connected to the support electrode 13a', the extraction electrode 12b' is connected to the support electrode 13b', the extraction electrode 12c' is connected to the support electrode 13c', and the extraction electrode 12d' is connected to the support electrode 13d'. has been done. In this way, excitation electrodes 11 and 11' are provided on both sides of the circular crystal piece 10, and two lead wires connected to these excitation electrodes are provided at the peripheral edge of the crystal piece 10. In the crystal resonator, the extraction electrodes 12a, 12
Among the support electrodes 13a, 13b, 13c, and 12d, the parts of the support electrodes that are not connected to the lead wires are peeled off to change the area of the opposing excitation electrodes, or the support electrodes 13a, 13b, 13c, and 1 are divided into four parts.
3d is partially peeled off to determine the facing area sandwiching the crystal piece 10.

When connecting a crystal resonator configured in this way to a lead wire, first position the tip of the lead wire 50 at an arbitrary point on the periphery of the front surface side 10a of the crystal resonator,
After contacting the support electrode 13c in this part, the lead wire 50 and the excitation electrode 11 are electrically connected by soldering this part or applying a conductive adhesive to the contact part. At the same time, the lead wire 50 is fixed to the crystal resonator.
Also, connect the tip of the lead wire 60 to the back side 1 of the crystal resonator.
After placing the lead wire at an arbitrary point on the periphery of 0b and contacting the supporting electrode, for example 13c', in this part, solder this part or apply a conductive adhesive to the contact part. 60 and the excitation electrode 11' are electrically connected, and the lead wire 60 is fixed to the crystal resonator.

At the time of inspection after completion of assembly, if the stray capacitance of the crystal resonator is larger than the designed value, the lead electrode to which the lead wire is not connected, for example, the lead electrode 12b in FIG. 2A, is cut at the point marked with an x. As a result of this cutting, the capacitor forming the capacitor facing the support electrode 13b' on the back surface side 10b is eliminated, so that the stray capacitance is substantially reduced. If it is desired to slightly reduce the stray capacitance, a part of the support electrode may be cut off without cutting off the extraction electrode. Note that a laser beam is used to cut the support electrode or extraction electrode.

3 to 6 all show conductive layer patterns on a crystal piece showing other embodiments,
In particular, FIG. 6 shows that the ends of the support electrodes are inclined so that they overlap each other when viewed from the center of the excitation electrode, and when the tip of the lead wire is located in the cut between the support electrodes, the lead wire This is to ensure smooth connection. Also, it is better to provide the connection point of the lead wire at a point offset from the diameter line. In addition, in FIGS. 3 to 6, 12 is an extraction electrode, and 13 is a support electrode.

As explained in detail above, in the present invention, one lead wire is connected at an arbitrary position of the support electrode provided piecemeal around the entire periphery of the front side, and the other lead wire is connected to the entire periphery of the back side. Since it is now possible to connect at any position on support electrodes that are provided piecemeal, there is no need to position the crystal piece and connect the lead wire and the connecting conductor as in the past. Fully automatic assembly of crystal units has become possible. In addition, stray capacitance can be easily adjusted by cutting out unnecessary parts of the leading electrodes and supporting electrodes on the front and back surfaces that form the counter electrodes at predetermined locations, providing a crystal resonator with uniform quality. Assembling and adjusting the crystal filter has become easier.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a conventional crystal resonator, Figure 2A
2B is an explanatory diagram illustrating the development of the crystal resonator according to the present invention, and FIGS. 3 to 6 are electrode pattern diagrams showing other embodiments. In the figure, 10 is a crystal piece, 11 and 11' are excitation electrodes, 12, 12a, 12a', 12b, 12b', 1
2c, 12c', 12d, 12d' are extraction electrodes, 1
3, 13a, 13a', 13b, 13b', 13c,
13c', 13d, 13d' are supporting electrodes, 50 and 6
0 is a lead wire.

Claims (1)

[Claims for Utility Model Registration] In a crystal resonator having excitation electrodes of the same area facing each other on both sides of the center of a disc-shaped crystal piece, and connecting lead wires to support electrodes drawn out from these excitation electrodes, At least one lead-out electrode is led out in the radial direction from the excitation electrode toward the edge of the crystal piece, and faces each other with the crystal piece in between; provided over almost the entire circumference of the edge,
A crystal resonator characterized in that it has the same number of support electrodes as the number of extraction electrodes which are respectively connected to the extraction electrodes and can be cut at predetermined locations.