JP4571012B2 - Crystal unit with pedestal - Google Patents

Description

The present invention relates to a surface mount crystal resonator (hereinafter referred to as a “base mount resonator”), and more particularly to a base mount resonator that prevents solder breakage and peeling due to a difference in thermal expansion coefficient from a set substrate. .

(Background of the Invention)
The pedestal resonator can be simply surface-mounted with a crystal resonator made of a conventional metal container, and is cheaper and more reliable than, for example, a surface mount type using a ceramic container. For this reason, for example, it is used as a frequency or time reference source in an in-vehicle electronic device.

(Example of conventional technology)
FIG. 6 is a diagram of a vibrator with a pedestal for explaining a conventional example. FIG. 6 (a) is a front view and FIG. 6 (b) is a side sectional view (see Patent Document 1). The vibrator with a pedestal is formed by mounting a pedestal 2 for surface mounting on the bottom surface of the crystal vibrator 1. In the crystal resonator 1, a pair of lead wires 3 that are airtight terminals made of glass (not shown) are led out from the bottom surface of the metal base 4. A crystal piece (not shown) is electrically connected to the lead wire 3 and held on the metal base 4 and covered with a cover 5 by resistance welding.

The pedestal 2 has a substantially rectangular shape larger than the metal base 4 and is composed of a pair of terminal boards 6 and a resin frame 7, and is formed by, for example, a resin mold. The pair of terminal boards 6 are separated from the upper surface of the resin frame 7, cross the short side direction, and bend to the back surface through the side surfaces (total of 4 terminals). Each of the pair of terminal boards 6 has a hole 8 at the center. Then, the pair of lead wires 3 of the crystal unit 1 are inserted into the holes 8 of the terminal plate 6 and connected from the back side by, for example, solder 9.

In such a case, for example, as shown in FIG. 7 (see Patent Document 2), the lead wire 3 of the crystal unit 1 is formed into a flat plate shape, penetrates the base 2, and is bent at both ends in the length direction. Compared with those (total of 2 terminals), the flat plate processing and bending processing of the lead wire 3 are not required, so the productivity is increased. Moreover, the breakage | damage etc. of the glass used as the airtight terminal which is the lead-out part of the lead wire 3 from the metal base 4, for example with a flat plate process or a bending process are prevented.

Further, since the pair of terminal boards 6 bent on the side surface of the base 2 are separated from the upper surface of the base 2, when the solder 9 is mounted on the set substrate 10 as shown in FIG. An electrical short circuit between the fillet and the metal base 4 is prevented. Here, since the pedestal 2 is made larger than the metal base 4, an electrical short circuit due to metal scraps is further prevented.
Japanese Unexamined Patent Publication No. Hei 8-102737 No. 1-222260 Japanese Utility Model Publication No.59-56784 Japanese Utility Model Publication No. 61-7124

(Problems of conventional technology)
However, when the vibrator with a base having the above-described structure is mounted on the set substrate 10, the following problems may occur due to the base 2 made of resin (plastic). That is, the pedestal vibrator is fixed to the circuit terminal (not shown) of the set substrate 10 by the solder 9 as described above. In this case, the set substrate 10 is generally made of a glass epoxy material, and the coefficient of thermal expansion is significantly different from that of the base 2.

From this, for example, in an environment where there is a large temperature difference for in-vehicle use, the expansion and contraction amount of the two differs as shown by the arrow due to the difference in thermal expansion coefficient between the pedestal-equipped vibrator and the set substrate 10. Stress occurs in 9A. In addition, there is a risk that damage (cracks) such as cracks and chips, and sometimes peeling may be caused to lower the reliability.

(Object of invention)
An object of the present invention is to provide a highly reliable vibrator with a pedestal that prevents damage or peeling of the solder 9 due to a difference in thermal expansion coefficient.

The present invention has a crystal resonator in which a pair of lead wires are led out from the bottom surface of the metal base and a pair of insertion holes through which the pair of lead wires penetrates, as indicated in the claims (Claim 1). And a pair of lead wires and a pedestal having a mounting terminal electrically connected to each of the side surface and the bottom surface, and a crystal vibration with a pedestal for surface mounting, wherein the pedestal is mounted on the bottom surface of the crystal resonator. In the child, the pedestal has a first substrate having a pair of insertion holes through which the pair of lead wires penetrates, and a diameter larger than the insertion holes communicating with the insertion holes and projecting from the tip of the lead wires to the inside. It consists of a laminated plate with a second substrate having a large lead wire protruding hole, and is electrically connected to the outer periphery of the insertion hole of the first substrate on the laminated surface side with the second substrate by the tip of the lead wire and solder An annular terminal electrode connected to the In addition, the mounting terminals are formed on the side surface and the bottom surface of the second substrate, and the annular terminal electrode and the mounting terminal are electrically connected through a laminated surface of the first substrate and the second substrate. And

In such a configuration, since the pedestal is formed from the laminated plate of the first substrate and the second substrate, the diameter is larger than the insertion hole through which the lead wire penetrates, and the lead wire protrudes to the inside and is electrically connected. A pedestal having a lead wire protruding hole can be easily obtained. And the laminated board which consists of a 1st board | substrate and a 2nd board | substrate can be made into the material which is the same as or close to the thermal expansion coefficient of the set board | substrate with which the vibrator with a base is mounted. In short, by using a laminated plate, the base 2 made of the same material as the set substrate can be easily formed.

(Embodiment of claim 1, claims 2 and 3)
In claim 2 of the present invention, the laminate is made of glass epoxy or ceramic material. Thereby, it can be made the same material as the material of a realistic set substrate.

According to the third aspect, the first substrate is a flat plate, and side surfaces located at both ends in the length direction of the second substrate have cutout portions in which the mounting terminals are formed. Cover the notch. This prevents an electrical short circuit between the solder fillet and the metal base when mounted on the set substrate, and an electrical short circuit due to metal debris or the like. And a base can be made into the magnitude | size below equivalent rather than a metal base.

FIGS. 1 and 2 are diagrams for explaining an embodiment of the present invention. FIG. 1 (a) is a schematic view of a vibrator with a pedestal, FIG. 1 (b) is a front sectional view, and FIG. It is an exploded view. In addition, description of the same part as a prior art example is simplified or abbreviate | omitted.

As described above, the pedestal resonator includes the surface mount base 2 having the mounting terminals 11 electrically connected to the lead wire 3 on the bottom surface of the metal base 4 from which the lead wire 3 of the crystal resonator 1 is led out. It is attached. The pedestal 2 is made of a laminated plate 12 of a first substrate 12a and a second substrate 12b, and is made of the same material glass epoxy material that is the same as or close to the thermal expansion coefficient of the set substrate 10 on which the pedestal-mounted vibrator is mounted.

The first substrate 12a and the second substrate 12b have a rectangular shape with the same outer shape larger than the metal base 4, the first substrate 12a has a flat plate shape (planar rectangular shape), and the second substrate 12b has both end portions (both ends) The surface) has a notch 13. Thereby, the first substrate 12a covers the cutout portion 13 of the second substrate 12b. The first substrate 12a has an insertion hole 14a through which the pair of lead wires 3 penetrates, and the second substrate 12b has a lead wire protruding hole 14b that communicates with the insertion hole 14a and the tip of the lead wire 3 protrudes inside. . The lead wire protruding hole 14b has a larger diameter than the insertion hole 14a.

An annular terminal electrode 11a is formed on the outer periphery of the insertion hole 14a of the first substrate 12a on the side of the laminated surface with the second substrate 12b. . In addition, mounting terminals 11 (side electrodes and bottom electrodes) are formed on the side and bottom surfaces of both end portions of the second substrate 12b, and terminals are formed by conductive paths 11b through the laminated surface of the first substrate 12a and the second substrate 12b. It is electrically connected to the electrode 11a. Here, the conductive path 11b includes a conductive electrode 11b1 extending from the terminal electrode 11a of the first substrate 12a and a bonding electrode 11b2 extending to the surface of the second substrate 12b.

These are the first substrate 12a formed of an annular electrode 11a and the conducting electrode 11 b 1, implementation terminal 11 (bottom electrode, a side electrode) and a second substrate 12b formed of and bonding electrodes 11b2, laminated by thermocompression Formed. Then, for example, as shown in FIG. 3, after the first sheet substrate 12A and the second sheet substrate 12B are laminated by thermocompression bonding, they are cut along the dividing lines XX and YY, and individual pedestals are obtained. Divided into two. In FIG. 3, electrodes are omitted for convenience.

That is, a pair of insertion holes 14a are formed in advance in the first sheet substrate 12A vertically and horizontally, and the annular terminal electrode 11a and the conductive path 11b described above extend in the opposite directions on the outer periphery of the insertion hole 14a. In the second sheet substrate 12B, electrode through holes (through holes) are formed in advance on the dividing lines (Y-Y) which are both ends in the length direction, and the side electrodes of the mounting terminals 11 are formed. Each electrode is made of copper foil and plated with gold. Then, the first sheet substrate 12A and the second sheet substrate 12B are laminated by thermocompression bonding, and then divided into individual pedestals 2.

With such a configuration, as described in the column of the effect of the invention, since the pedestal 2 is formed from the laminated plate 12 of the first substrate 12a and the second substrate 12b, the insertion hole 14a through which the lead wire 3 passes is formed. The pedestal 2 having a larger lead diameter and a lead wire protruding hole 14b through which the lead wire 3 protrudes and is electrically connected can be easily obtained. For example, it is suitable for mass production using a sheet method using the first sheet substrate 12A and the second sheet substrate 12B.

Here, since the laminated plate 12 composed of the first substrate 12a and the second substrate 12b is made of the same material as the set substrate 10 composed of the glass epoxy material on which the vibrator with the base is mounted, the stress due to the difference in thermal expansion coefficient is applied. This reduces the damage and prevents the solder 9 from being broken or peeled off. And since the 1st board | substrate 12a is a flat plate and covers the notch part 13 of the 2nd board | substrate 12b, it is by the electrical short circuit of the solder 9 fillet and the metal base 4 at the time of mounting to the set board | substrate 10, and metal waste etc. Prevent electrical short circuit.

FIG. 4 is a front sectional view of a vibrator with a base for explaining a second embodiment of the present invention. In the first embodiment, the pedestal 2 is made larger than the metal base 4, but in the second embodiment, it is equal to or less than that of the metal base 4. In this way, the vibrator with a pedestal can be made smaller than the planar outer shape of the crystal resonator 1, and the mounting density of the set substrate 10 can be increased. Even in this case, the cutout portions 13 provided at both ends of the second substrate 12b are covered with the first substrate 12a, so that an electrical short circuit with the side electrode of the mounting terminal 11 is prevented.

FIG. 5 is a diagram of a vibrator with a base for explaining a third embodiment of the present invention. In the first and second embodiments, the lead wire protruding hole 14b of the second substrate 12b is provided independently corresponding to the insertion hole 14a of the first substrate 12a, but in the third embodiment, it is a single hole. If it does in this way, soldering work of the lead wire 3 and the cyclic | annular terminal electrode 11a will become easy, so that size reduction progresses and the base 2 becomes small.

(Other matters)
In each of the above embodiments, the mounting terminals 11 are formed at both ends in the length direction. However, it is needless to say that the mounting terminals 11 may be formed at both ends in the width direction as in the conventional example, for a total of four terminals. Moreover, although the base 2 is made of a glass epoxy material, it can be made of a ceramic material according to the set substrate, for example. In this case, a laminated board made of ceramic is formed by firing after forming each electrode by metallization.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure explaining one Embodiment of this invention, The figure (a) is a general-view figure of the vibrator with a base, The figure (b) is a partial front sectional view. It is an exploded view of the pedestal explaining one embodiment of the present invention. It is a figure of a sheet substrate explaining one embodiment of the present invention. It is a partial front sectional view of a vibrator with a base for explaining a second embodiment of the present invention. It is a partial front sectional view of a vibrator with a base for explaining a third embodiment of the present invention. It is a figure of the vibrator with a base explaining a prior art example, the figure (a) is a front view and the figure (b) is a partial sectional side view. It is a partial front sectional view of a vibrator with a base for explaining a conventional example. It is a partial sectional side view of the vibrator with a base explaining the problem of a prior art example.

DESCRIPTION OF SYMBOLS 1 Crystal oscillator, 2 base, 3 lead wire, 4 base, 5 cover, 6 terminal board, 7 resin frame, 8 hole, 9 solder, 10 set board, 11 mounting terminal, 12 laminated board, 13 notch part, 14a insertion Hole, 14b Lead wire protruding hole.

Claims (3)

A side surface of a mounting terminal that has a pair of lead holes from which a pair of lead wires are led out from the bottom surface of the metal base and has a pair of insertion holes through which the pair of lead wires penetrates and is electrically connected to the pair of lead wires. And a pedestal having a pedestal on the bottom surface, wherein the pedestal has a pair of insertion holes through which the pair of lead wires penetrates. A laminated board of a first board having a second board having a lead wire projecting hole having a diameter larger than the insertion hole through which the tip end portion of the lead wire projects inward and communicates with the insertion hole; An annular terminal electrode is formed on the outer periphery of the insertion hole of the first substrate on the side of the laminated surface with the two substrates, and is electrically connected to the tip of the lead wire by solder, and the mounting terminal is Side and bottom of 2 substrates Is formed, the base crystal unit with, characterized in that said annular terminal electrode and the mounting terminal electrically connected via the lamination surfaces of the said first substrate second substrate. The pedestal-attached crystal resonator according to claim 1, wherein the laminated plate is made of ceramic or glass epoxy material. The first substrate is a flat plate, and side surfaces located at both end portions in the length direction of the second substrate have cutout portions in which the mounting terminals are formed, and the first substrate covers the cutout portions. The crystal resonator with a pedestal according to claim 1.

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