JPH0149048B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a two-resonator type piezoelectric resonator and a method for manufacturing this resonator.

A piezoelectric resonator, such as an energy-trapped piezoelectric ceramic resonator that utilizes thickness longitudinal or thickness shear vibration, is designed as shown in Figures 1 and 2 in order to reduce the vertical space when mounted on a printed circuit board. In addition, a low-profile structure with a small vertical height H is adopted.

The above-mentioned low-profile structure is obtained by forming the piezoelectric substrate 1 into a horizontally long rectangular shape, cutting down the vertical height, providing electrodes 2 on both sides of the piezoelectric substrate 1, and connecting lead terminals 3 and 4 to both ends by soldering. , the side surface of the board 1 is covered with a dip exterior 5, but in such a structure in which the lead terminals 3 and 4 are soldered, the solder extends to the vibrating electrode part of the electrode when soldering, causing vibration. must be ensured so as not to impede the

By the way, in the single-resonator type resonator shown in FIG. 1, the electrodes 2 provided on both sides of the piezoelectric substrate 1 are formed with the vibrating electrode part 6, the external extraction terminal part 7, and the lead-out part 8 arranged in reverse. Therefore, the distance between the soldered parts of the lead terminals 3 and 4 and the vibrating electrode part, that is, the length l of the lead-out part 8, can be increased, and the solder does not reach the vibrating electrode part 6 during soldering. It doesn't stretch so it's not a problem.

However, the one-resonator type resonator has a drawback in that the external terminal portions 7 to which the lead terminals 3 and 4 are soldered are located on opposite sides of the piezoelectric substrate 1.

On the other hand, the series two-resonance type resonator shown in FIG. Since the piezoelectric substrate 1 has a structure in which a counter electrode 9 corresponding to both vibrating electrode portions 6, 6 is provided on the surface side, the lead terminals 3, 4 can be aligned and attached to one surface side of the piezoelectric substrate 1.

However, since the two-in-series resonator type resonator requires two vibrating electrode sections 6 to be lined up on one side of the piezoelectric substrate 1, the length l' of the lead-out section 8 becomes extremely short, and the solder There is a problem in that it extends to the vibrating electrode section 6.

In order to solve this problem, the interval between the vibrating electrode parts 6
It is conceivable to reduce l'' and increase the length l' of the lead-out portion 8, but such a method would result in elastic coupling between the two resonators due to the proximity of both vibrating electrode portions 6, and the required Since electrical characteristics cannot be obtained, the interval l'' must be set to a distance that does not result in elastic coupling, and it is difficult to increase the length l of the pull-out portion 8.

This invention was made to solve the problems encountered with the two-resonance type piezoelectric resonator as described above, and the lead-out part of the electrode is long, and the solder when soldering the lead terminal reaches the vibrating electrode part. It is an object of the present invention to provide a piezoelectric resonator that is reliable and a manufacturing method that can efficiently mass-produce the piezoelectric resonator.

A first configuration of the present invention includes two vibrating electrode sections on one side of the piezoelectric substrate and external extraction terminal sections at both ends.
A lead-out part connecting the vibrating electrode part and its external terminal part is provided, and a counter electrode corresponding to both the vibrating electrode parts and connected to each other is provided on the other side, and the lead-out part is arranged along the side edge of the piezoelectric substrate. By making a detour and increasing the distance of the lead-out portion, the solder connecting the lead terminal does not reach the vibrating electrode portion.

A second configuration of the present invention has two vibrating electrode parts on one surface side of the mother piezoelectric substrate, external lead-out terminal parts on both sides thereof, and extending in opposite directions from the vibration electrode part, with a part extending toward the external lead-out terminal part. A plurality of electrodes are arranged so that the lead parts are common, and counter electrodes are connected to each other at positions corresponding to the vibrating electrode parts of each electrode on the other side of the mother piezoelectric substrate. After that, the mother piezoelectric substrate is cut at the position of the lead-out part for each electrode to cut out the piezoelectric vibrator, so that even if positional deviation occurs during cutting, the lead-out part of the electrode can be secured.

Embodiments of the present invention will be described below with reference to FIGS. 3 and 4 of the accompanying drawings.

As shown in FIG. 3, a mother piezoelectric substrate 11 of an appropriate size is prepared, and multiple sets of electrodes 12 are placed on one side of the mother piezoelectric substrate 11.
Form by arranging them vertically and horizontally.

The electrode 12 has two vibrating electrode parts 13, 13 provided apart from each other by a distance that does not cause elastic coupling, and external lead-out terminal parts 14, 14 provided on both sides sandwiching both the vibrating electrode parts 13, 13. , each vibrating electrode section 13
and a drawer part 1 for connecting the external extraction terminal part 14.
5, this lead-out part 15 includes a vertical lead-out part 15a extending in opposite directions from the vibrating electrode part 13 and parallel to the external extraction terminal part 14;
It is formed by a horizontal lead-out part 15b that is bent from the vertical lead-out part 15a to reach the external lead-out terminal part 14, and connects the vibrating electrode part 13 and the external lead-out terminal part 14 to
They are connected by two drawer portions 15 that detour in a letter shape.

The lead-out portion 15 of the electrode 12 can have a long distance due to the L-shaped detour, and the solder connecting the lead terminal to the external extraction terminal portion 14 can extend to the vibrating electrode portion 13 without increasing the length of the piezoelectric substrate. You can get unprecedented length.

As shown in FIG. 3, these electrodes 12 are formed into multiple sets by printing or other methods so that the horizontal lead-out parts 15b of the lead-out parts 15 are connected to each other on the upper and lower sides, and the external lead-out terminal parts 14 are connected to each other on both sides. Arrange and form.

Further, on the other side of the mother piezoelectric substrate 11, counter electrodes 16, 16 and an electrode 16' connecting them to each other are integrally provided at positions corresponding to the vibrating electrode parts 13, 13 of each electrode 12.

In this way, the electrode 12 and the counter electrode 1 are placed on both sides.
The mother piezoelectric substrate 11 on which the electrodes 6 and 16' are provided is cut vertically and horizontally by a cutting wheel in units of each electrode 12, and the piezoelectric vibrator 17 shown in FIG. 4 is cut out.

The cutting position of the mother piezoelectric substrate 11 is as shown by the dashed line in FIG. 3, so that the external lead terminal portion 14 of the adjacent electrode 12 and the horizontal lead portion 15b of the lead portion 15 are each cut into two.

For example, the dimensions of the piezoelectric vibrator 17 after cutting are approximately 2.4 mm in height, 6.7 mm in width, and 0.7 mm in thickness, and the width of the lead-out portion 15 of the electrode 12 in this piezoelectric vibrator 17 is 0.1 to 0.3 mm. It has a very narrow width.

For this reason, if the drawer part 15 is formed only on one of the upper and lower sides, the horizontal drawer part 15b of the drawer part 15 will break or become in a state of being about to break due to a slight positional shift during cutting. Yield and reliability will decrease.

On the other hand, in the present invention, since two lead-out portions 15 are formed between the vibrating electrode portion 13, if the cutting position shifts for some reason and is cut at the position shown by the two-dot chain line in FIG. Even if one of the lead-out parts 15 is disconnected, the connection between the vibrating electrode 13 and the external terminal part 14 is maintained by the other lead-out part 15.

Lead terminals 18 and 19 are connected to the external terminal portions 14 and 14 at both ends of the cut piezoelectric vibrator 17 by soldering, respectively, and the outer periphery of the piezoelectric substrate is covered with a dip exterior 20 to complete the piezoelectric vibrator 17 as a product.

As described above, according to the present invention, two vibrating electrode parts, an external extraction terminal part, and a lead-out part are provided on one side of a piezoelectric substrate formed in a rectangular shape, and the two vibrating electrode parts, an external extraction terminal part, and a lead-out part are provided on the other side of the piezoelectric substrate. In addition, counter electrodes connected to each other are provided, and the extraction portion is detoured along the side edge of the piezoelectric substrate. Therefore, in a low-profile series two-resonance type piezoelectric resonator, the piezoelectric substrate can be extracted without increasing its length. The solder that connects the lead terminal to the external extraction terminal does not extend to an area that would interfere with the vibration of the vibrating electrode by passing through the lead-out part, and the oscillation accuracy can be improved with a small size. It is possible to provide an excellent series two-resonance type resonator.

In addition, on one side of the mother piezoelectric substrate, there is a vibrating electrode part, an external lead-out terminal part, and two lead-out parts that go in opposite directions from the vibrating electrode part and bend halfway toward the external lead-out terminal part. A plurality of electrodes are arranged side by side so that the lead-out parts are connected, and counter electrodes connected to each other are provided at positions corresponding to the vibrating electrode parts of each electrode on the other side of the mother piezoelectric substrate,
The piezoelectric resonators were cut out by cutting the mother piezoelectric substrate at the position of the lead-out part for each electrode.
Even if misalignment occurs during cutting, one of the two lead-out parts will remain securely, ensuring continuity between the vibrating electrode part and the external terminal part, eliminating breakage of the lead-out part, and greatly improving yield and reliability. You can make improvements.

Furthermore, the positioning accuracy in cutting the mother piezoelectric substrate can be relaxed, and piezoelectric resonators can be efficiently mass-produced by reducing the number of man-hours and generalizing the work.

[Brief explanation of drawings]

Figure 1 is a front view of a conventional one-resonator type resonator, Figure 2 is a front view of a conventional two-resonator type resonator,
3 and 4 show the manufacturing process of the present invention, with FIG. 3 being a front view showing electrodes provided on the mother piezoelectric substrate, and FIG. 4 being a front view of the completed resonator. 11... Mother piezoelectric substrate, 12... Electrode, 13
... Vibration electrode part, 14 ... External extraction terminal part, 1
5...Drawer part, 15a...Vertical drawer part, 15b...
Lateral lead-out portion, 16... counter electrode, 17... piezoelectric resonator, 18, 19... lead terminal, 20... dip exterior.

Claims (1)

[Claims] 1. On one surface side of a piezoelectric substrate formed in a rectangular shape, external extraction terminal portions formed at both ends of this substrate;
Two vibrating electrode parts are formed between the two extraction terminal parts, and at least two or more extraction parts are formed to connect each vibration electrode part and the external extraction terminal part. A counter electrode is provided on the surface side that corresponds to both vibrating electrode parts and is connected to each other, and a lead-out part connecting the vibrating electrode part and the external lead-out terminal part is formed so as to detour along both side edges of the piezoelectric substrate. A piezoelectric resonator characterized by: 2. In order to connect the pair of external extraction terminal parts, the two vibrating electrode parts located between both extraction terminal parts, and the vibration electrode part and the external extraction terminal part, the vibration electrode part extends in opposite directions from the vibration electrode part, and A plurality of sets of electrodes each having a lead-out part bent toward an external extraction terminal part are arranged side by side on one side of the mother piezoelectric substrate so that the lead-out part is common, and each set is arranged on the other side of the mother piezoelectric substrate. A method for manufacturing a piezoelectric resonator, comprising: providing a counter electrode that corresponds to the vibrating electrode portion of the electrode and is connected to each other; and cutting the mother piezoelectric substrate parallel to the lead-out portion for each electrode.