JP2005260600A - Crystal oscillator for surface mounting - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a geometrically stable surface mounting oscillator with enhanced bonding strength which prevents solder from being cracked by dispersing the stress, especially, caused by thermal shock and realizes the sure electrical connection. <P>SOLUTION: The crystal oscillator for surface mounting has at least a mounting terminal electrically connected with a crystal piece on both end sides in the lengthwise direction on the rear face of a container body to which the crystal piece is mounted. The crystal oscillator is constituted so that a reinforcing terminal is provided on both sides in the widthwise direction as the central part in the lengthwise direction, and the mounting terminal and the reinforcing terminal are electrically connected in common. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a surface mount crystal resonator (hereinafter referred to as a surface mount resonator) in the technical field, and more particularly to an in-vehicle surface mount resonator having improved connection strength and good thermal shock characteristics.

(Background of the Invention) Since a surface-mounted resonator does not have a lead wire as a terminal, it has less electromagnetic radiation and is suitable for EMI countermeasures. Therefore, in recent years, it is applied as an oscillation source of many electronic control devices including, for example, an engine control device of an automobile.

(Example of Prior Art) FIG. 3 is a view of a surface-mounted vibrator for explaining one conventional example. FIG. 3 (a) is a sectional view and FIG. 3 (b) is a plan view excluding a cover.

  The surface mount vibrator is formed by housing a crystal piece 2 in a container body 1 having a concave shape, covering the cover 3, and sealing the crystal piece 2. The container body 1 is made of a laminated ceramic having a bottom wall 4 and a frame wall 5. A pair of terminal electrodes 6 are provided on the inner bottom surface of the container body 1, and both ends of one end of the crystal piece 2 are fixed by a conductive adhesive 8 to be electrically and mechanically connected.

  The pair of terminal electrodes 6 are provided on one end side of the container body 1, and the conductive path 7 extends, and extends to the back surface on both end sides through the laminated surface by through holes. And it electrically connects with a pair of crystal terminal 9 (ab). The crystal piece 2 has excitation electrodes (not shown) on both main surfaces, and extends extraction electrodes on both sides of one end.

  In general, when the cover 3 is made of an insulating material such as ceramic and is made of glass or resin sealing (not shown), the pair of crystal terminals 9 (ab) are formed at the center portions on both end sides in the length direction. FIG. 4 (a) ".

  Further, when the cover 3 is made of metal, a crystal terminal 9 (ab) is provided at a pair of diagonal portions (FIG. 4B). The other diagonal portion is provided with a ground terminal 9 (cd) electrically connected to the metal cover 3 through a through hole or the like. In these cases, a metal ring or a thick metal film is provided on the upper surface of the container body 1 and joined by seam welding, an electron beam, or the like. The crystal terminal 9 (ab) and the ground terminal 9 (cd) are mounting terminals for surface mounting on a set substrate (not shown).

  The surface mount vibrator is placed on a cream solder applied to a circuit terminal on a set substrate (not shown), and is transported and mounted on a high heat path. Further, the mounting terminal 9 has end surface electrodes 10 by through holes on the side surface and corners of the bottom wall 4 and confirms melting of solder by forming a so-called solder fillet (not shown) during mounting.

(Problem of the prior art) However, the crystal resonator having the above-described configuration is mounted on, for example, a set substrate constituting a control device and left in a car regardless of day or night. In particular, the temperature difference between the engine and the place exposed to direct sunlight is severe. In addition, impact and vibration are caused during movement.

  For this reason, the expansion coefficient differs from that of a set substrate made of, for example, a glass epoxy material, and cracks (chips, cracks, etc.) are generated, for example, at the solder base due to repeated stress due to thermal strain. In the worst case, there is a problem of causing peeling and hindering electrical conduction.

(Object of the Invention) An object of the present invention is to provide a surface-mounted vibrator that can prevent cracking due to thermal shock and ensure electrical connection.

  In this invention, as shown in the claim (Claim 1), it has the mounting terminal electrically connected with the said crystal piece at least in the both ends of the length direction in the back surface of the container main body which accommodated the crystal piece. The surface-mounting crystal resonator has a configuration in which reinforcing terminals for reinforcement are provided on both sides in the width direction in the center in the length direction, and the mounting terminals and the reinforcing terminals are electrically connected in common.

  With such a configuration, since the reinforcing terminal for reinforcement is provided in addition to the mounting terminal, for example, stress due to thermal strain is distributed to the mounting terminal and the reinforcing terminal, thereby preventing the occurrence of cracks. Further, even if the stress is concentrated on the mounting terminal and the electrical conduction is hindered by peeling or the like, the electrical conduction can be secured by the reinforcing terminal. Furthermore, since the reinforcing terminal is the central part in the width direction, it is geometrically stable and increases the bonding strength.

  According to a second aspect of the present invention, the container body of the first aspect is made of a multilayer ceramic, and the mounting terminal and the reinforcing terminal are electrically connected through a multilayer surface of the multilayer ceramic. Thereby, since the wiring pattern is not exposed on the back surface, an electrical short circuit with the circuit pattern on the set substrate is prevented.

  In the third aspect, the mounting terminal according to the first or second aspect includes a crystal terminal electrically connected to the crystal piece, and is located at both ends in the length direction on the back surface of the container body and in the center in the width direction. Placed in. As a result, the location of the surface-mounted vibrator and the mounting terminals whose mounting terminals are only crystal terminals is clarified.

  In claim 4, the mounting terminal of claim 1, 2 or 3 comprises a crystal terminal electrically connected to the crystal piece and a ground terminal electrically connected to a metal cover for sealing the container body. The crystal terminals are arranged at a pair of diagonal portions at both ends in the length direction on the back surface of the container body, and the ground terminals are at both ends of the length direction at another set of diagonal portions. Placed in. As a result, the surface mounting vibrator whose mounting terminals are the crystal terminal and the ground terminal and the location of the mounting terminals are clarified.

  FIG. 1 is a back view of a surface-mount resonator, particularly a container body, illustrating a first embodiment of the present invention, and is an example in which only a crystal terminal is arranged on the back surface of a container body. In addition, the same number is attached | subjected to the same part as a prior art example, and the description is simplified or abbreviate | omitted.

  As described above, the surface-mounted vibrator is formed by bonding a cover 3 made of insulating ceramic by containing a crystal piece 2 in a container body 1 made of a laminated ceramic having a bottom wall 4 and a frame wall 5 by resin or glass sealing. The piece 2 is hermetically sealed (see FIG. 3 above). Then, the crystal terminals 9 (ab) that are electrically connected to the terminal electrodes 6 to which both ends of one end of the crystal piece 2 are fixed are at both ends in the length direction on the back surface of the container body 1 and at the center in the width direction. Provided as a mounting terminal.

  Further, here, a pair of reinforcing terminals 11 (ab) are provided on both sides in the width direction and at the center in the length direction. And each one and each other of a pair of crystal terminal 9 (ab) and a pair of reinforcement terminal 11 (ab) are electrically connected in common by the conductive path 7 which passed through the laminated surface of a side surface, a bottom wall, and a frame wall. Is done.

  With such a configuration, by providing the reinforcing terminal 11 (ab), it is possible to increase the connection strength and disperse the stress caused by the thermal strain to the crystal terminal 9 (ab) and the reinforcing terminal 11 (ab). Accordingly, solder cracks are prevented. And even if the crystal terminal 9 (a or b) peels, the reinforcement terminal 11 (a or b) connected in common with this will ensure electrical connection with the set substrate. The circuit terminals of the set substrate connected to the crystal terminal 9 (ab) and the reinforcing terminal 11 (ab) are similarly connected in common.

  FIG. 2 is a back view of the surface-mounted vibrator, particularly the container body, for explaining the second embodiment of the present invention, and is an example in which a crystal terminal and a ground terminal are arranged on the back surface of the container body. In addition, description of the same part as a previous Example is simplified or abbreviate | omitted.

  In the second embodiment, the cover 3 made of metal is joined to the container body 1 in which the crystal piece 2 is sealed by seam welding or the like. And the crystal terminal 9 (ab) connected to the crystal piece 2 is arrange | positioned at a pair of diagonal part of a length direction on the both ends in the back surface of the container main body 1. FIG. Further, the ground terminals 9 (cd) connected to the cover 3 are arranged at other diagonal portions in the length direction.

  Even in this case, a pair of reinforcing terminals 11 (ab) are provided at the center in the length direction and on both sides in the width direction. Each one and the other of the pair of crystal terminals 9 (ab) and the pair of reinforcing terminals 11 (ab) are electrically connected to each other by a conductive path passing through the side surface, the laminated surface of the bottom wall and the frame wall as described above. (Not shown).

  As a result, as in the first embodiment, the stress caused by thermal strain is distributed to the crystal terminals 9 (ab) and the reinforcing terminals 11 (ab) to prevent solder cracks. Even if it peels off, the reinforcing terminal 11 (ab) ensures electrical connection with the set substrate.

(Other matters) In the above embodiment, the container body 1 has a concave shape and the cover 3 has a flat plate shape. However, the same can be applied to the case where the container main body 1 has a flat plate shape and the cover 3 has a concave shape. In this case, for example, the plate-like container body 1 may be formed into two layers, and the terminal electrode 6 and the crystal terminal 9 (ab) may be connected through the through hole and the laminated surface, and further connected to the reinforcing terminal 11 in common.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure of the surface mount vibrator | oscillator explaining 1st Example of this invention, The figure (a) is a back view of a container main body, The figure (b) is a top view except a cover. FIG. 2 is a back view of the surface mount vibrator, particularly the container body, for explaining the second embodiment of the present invention. It is a figure of the surface mounting vibrator | oscillator explaining a prior art example, the figure (a) is sectional drawing, the figure (b) is a top view except a cover. It is a figure explaining a prior art example, The figure (ab) is a back view of a surface mount oscillator.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Container body, 2 Crystal piece, 3 Cover, 4 Bottom wall, 5 Frame wall, 6 Terminal electrode, 7 Conductive path, 8 Conductive adhesive, 9 Mounting terminal, 10 End surface electrode, 11 Reinforcement terminal.

Claims (4)

  In a surface-mount crystal resonator having at least mounting terminals electrically connected to the crystal piece on both ends in the length direction on the back surface of the container body on which the crystal piece is mounted, the center portion in the length direction A crystal resonator, wherein reinforcing terminals are provided on both sides in the width direction, and the mounting terminal and the reinforcing terminal are electrically connected in common.   2. The crystal resonator according to claim 1, wherein the container body is made of a laminated ceramic, and the mounting terminal and the reinforcing terminal are electrically connected in common through a side surface and a laminated surface of the laminated ceramic.   3. The crystal according to claim 1, wherein the mounting terminal includes a crystal terminal electrically connected to the crystal piece, and is disposed at both ends in the length direction on the back surface of the container body and at the center in the width direction. Vibrator.   4. The mounting terminal according to claim 1, wherein the mounting terminal includes a crystal terminal that is electrically connected to the crystal piece and a ground terminal that is electrically connected to a metal cover that seals the container body. Quartz disposed on both ends in the length direction on the back surface of the container main body and disposed in a pair of diagonal portions, and the ground terminal is disposed on both ends in the length direction and disposed in another diagonal portion. Vibrator.

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