JP2007129520A - Piezoelectric vibrator and surface-mounted piezoelectric vibrator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To be able to provide a piezoelectric vibrator which maintains high airtightness and is a smaller cylinder type package, and at the same time, to provide a small surface-mounted piezoelectric vibrator whose height is 0.9 mm or less and which is easy to reduce mounting space by mounting the piezoelectric vibrator. <P>SOLUTION: In the piezoelectric vibrator; a lead terminal is arranged in a center position of an airtight terminal, an inner lead unit has a flat step difference plane which is parallel to a center line of the airtight terminal and separated by a predetermined distance from the center line, and the piezoelectric reed is supported by the flat step difference plane so as to be nearly in the center position of a sealed tube and in parallel. Moreover, the surface-mounted piezoelectric vibrator of electrode terminals is consisted of a vertical unit in which an airtight terminal side vertically crosses with a lengthwise direction of the piezoelectric vibrator, and a seal tube side is parallel to the lengthwise direction of the piezoelectric vibrator; and a horizontal unit to which external electrodes are connected. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a piezoelectric vibrator and a surface-mount piezoelectric vibrator that house a piezoelectric vibrating piece such as a quartz vibrator inside a cylindrical cylinder-type package, and more particularly to surface mounting on a small piezoelectric vibrator and an external substrate. The present invention relates to a suitable surface-mount type piezoelectric vibrator.

  As an electronic element indispensable for manufacturing industrial products such as a timepiece, an oscillator, and an electronic device, there is a piezoelectric vibrator, which is used as a time source, a timing source, or a signal reference source. A cylindrical cylinder type package is commonly used as a package of a piezoelectric vibrator. The configuration of the piezoelectric vibrator of the cylinder type package will be described with reference to the drawings.

  FIG. 11 is an exploded perspective view showing a configuration of a piezoelectric vibrator of a cylinder type package. As shown in FIG. 11, in the piezoelectric vibrator 6 of the cylinder type package, the piezoelectric vibrating reed 4 is joined to the inner lead 2 inside the airtight terminal 1 having two lead terminals. The piezoelectric vibrating piece 4 is made of a piezoelectric material such as quartz, and is formed in a tuning fork shape by a photolithography technique. Excitation electrodes 4 a are formed on the surfaces of the two vibrating arms of the tuning fork-type piezoelectric vibrating piece 4. On the surface of the piezoelectric vibrating reed 4 on the airtight terminal 1 side, a mount electrode 7 connected to the excitation electrode 4a is formed.

  The piezoelectric electrode 4 and the inner lead 2 inside the hermetic terminal 1 are joined by the mount electrode 7. The inner lead 2 penetrates through the airtight terminal 1 to become an outer lead 3, and the inner lead 2 and the outer lead 3 are collectively referred to as a lead terminal. The outer periphery of the hermetic terminal 1 is covered with a sealing tube 5 of a cylindrical bottomed cylinder made of metal so as to cover the tuning-fork type piezoelectric vibrating piece 4 and hermetically sealed in a vacuum.

  When a predetermined voltage is applied as a drive voltage to the two outer leads 3, the current flows from the inner lead 2 to the excitation electrode 4 a via the mount electrode 7 in the cylinder-type package piezoelectric vibrator configured as described above. The piezoelectric vibrating piece 4 oscillates at a predetermined frequency.

  The piezoelectric vibrator 6 of the cylinder type package as described above cannot be surface-mounted using an automatic mounting machine, unlike other electronic components, so that the piezoelectric vibrator 6 of the cylinder type package is covered with resin. 2. Description of the Related Art A surface-mount type piezoelectric vibrator that is molded into a shape and made surface-mountable using an automatic mounting machine is known.

  12 and 13 are views for explaining a surface-mount type piezoelectric vibrator, FIG. 12 is an external perspective view, and FIG. 13 is a schematic cross-sectional view showing an internal structure in a state where a resin is cut.

  As shown in FIGS. 12 and 13, in the surface mount piezoelectric vibrator 10, the piezoelectric vibrator 6 is installed at the center, and the outer lead 3 is mounted on the external substrate at the tip side. The electrode terminal 11 is provided. The electrode terminal 11 is bent in a crank shape. One end of the electrode terminal 11 serves as a joint portion with the outer lead 3 and the other side serves as a substrate mounting portion. The substrate mounting portion is a surface-mounted piezoelectric vibration. The shape is arranged so as to face outward of the child 10.

  In recent years, miniaturization of products using electronic components has been further advanced, and there is a strong demand for thinning to reduce the height of electronic elements, miniaturization of substrates, and reduction of the mounting area of the surface-mount piezoelectric vibrator 10. Has been. The thinning of the surface-mounted piezoelectric vibrator 10 that houses the cylindrical cylinder-type piezoelectric vibrator 6 largely depends on the outer diameter of the piezoelectric vibrator 6.

  As shown in FIG. 13, the conventional surface-mounted piezoelectric vibrator 10 on which the above-described cylindrical cylinder-type package piezoelectric vibrator 6 is mounted has a height of 1.4 mm and a length of 7 mm. The outer diameter of the piezoelectric vibrator 6 housed in the surface-mounted piezoelectric vibrator 10 is φ1.2 mm. For this reason, it has been difficult to obtain the surface mount piezoelectric vibrator 10 having a height of 0.9 mm or less. The sectional structure of the piezoelectric vibrator 6 will be described with reference to the drawings.

  FIG. 14A is a cross-sectional view taken along the line AA in FIG. The main dimensions of the conventional piezoelectric vibrator 6 having an outer diameter of φ1.2 mm are as follows. The outer diameter of the sealing tube 5 is φ1.04 mm, and the inner diameter is φ0.88 mm. At the center of the sealing tube 5, two inner leads 2 having a wire diameter of 0.15 mm are arranged symmetrically with a distance of 0.3 mm from each other. The piezoelectric vibrating reed 4 has a width of about 0.45 mm to 0.55 mm and a thickness of about 100 μm, and is bonded on the tangent line of the two inner leads 2. Therefore, the piezoelectric vibrating reed 4 has a structure that deviates from the center of the sealing tube 5 and is biased toward the inner wall of the sealing tube 5.

  In order to obtain a surface mount piezoelectric vibrator of 0.9 mm or less from the conventional surface mount piezoelectric vibrator 10 having a height of 1.4 mm, at least a piezoelectric vibrator having an outer diameter of φ0.8 mm or less is required. Will be.

  Therefore, the outer diameter of the sealing tube 5 is set to φ0 based on the cross-sectional dimension assigned from the outer diameter of about φ0.8 mm in the structure of the conventional piezoelectric vibrator 6 connected on the tangent line of the two inner leads 2. The problem of miniaturization in which the outer diameter of the piezoelectric vibrator 6 is not more than φ0.8 mm when the inner diameter of the sealing tube 5 is φ0.65 mm will be described.

  FIG. 14B shows a case where the outer diameter of the sealing tube 5 is φ0.75 mm and the inner diameter of the sealing tube 5 is assumed to be reduced to φ0.65 mm. 3 is a cross-sectional view of a piezoelectric vibrator 6 bonded on a tangent line of an inner lead 2. FIG.

The piezoelectric vibrator 6 is clearly shown in FIG.
1) In the conventional structure in which the two inner leads 2 are arranged at the center of the sealing tube 5, the piezoelectric vibrating reed 4 is biased toward the sealing tube 5. For this reason, there is no distance between the piezoelectric vibrating reed 4 connected on the tangent line of the two inner leads 2 and the inner wall of the sealing tube 5, and the piezoelectric vibrating reed 4 interferes with the inner wall of the sealing tube 5. That is, it is difficult to store the piezoelectric vibrating reed 4 having a width of about 0.45 mm to 0.55 mm and a thickness of about 100 μm in the sealing tube 5.

  2) As the size is reduced, the ratio of the wire diameter of the inner lead 2 to the inner diameter of the sealing tube 5 increases, and when the outer diameter of the piezoelectric vibrator 6 is 0.8 mm or less, the conventional two inner leads 2 are airtight. The distance from the inner diameter of the metal ring 7 of the terminal 1 is almost eliminated. It becomes difficult to store the two inner leads 2 in the inner diameter of the metal ring 7 of the airtight terminal 1 while keeping the diameter of the conventional two inner leads 2 as it is.

  3) If the wire diameter of the inner lead 2 is smaller than the conventional φ0.15 mm, problems such as insufficient support rigidity of the piezoelectric vibrating reed 4 and deformation of the inner lead 2 occur, which is the limit of miniaturization.

  As an example for solving the thinning problem of the piezoelectric vibrator 6, the piezoelectric vibrator 6 can be thinned by using an elliptical or substantially elliptic cylindrical case. An example of such a container is disclosed in Patent Document 1. According to the configuration disclosed in Patent Document 1, the metal ring has a flat shape, and the inner lead has an airtight terminal structure that is eccentric, bent, and sealed.

  However, in the airtight terminal in which the metal ring is flat like the airtight terminal disclosed in Patent Document 1, since the thickness of the piezoelectric vibrator is approximately 1.0 mm, the surface mount type has a height of 0.9 mm or less. It was difficult to obtain a piezoelectric vibrator.

  In addition, as a problem specific to the flat airtight terminal, there are problems such as difficulty in aligning the press-fitting direction and airtight leakage due to a contact surface pressure difference as the size is reduced.

  As described above, in the piezoelectric vibrator, in the structure in which two conventional inner leads are arranged at the center of the sealing tube, or in the structure in which the two inner leads are eccentric and the piezoelectric vibrating piece is connected on the tangent line of the inner lead. There was a limit to downsizing the outer diameter φ0.8 mm.

  On the other hand, Patent Document 2 and Patent Document 3 are examples in which one inner lead is used in order to solve the problem of miniaturization without using a flat airtight terminal.

  According to the structures disclosed in Patent Document 2 and Patent Document 3, an electrode formed on the surface of the piezoelectric vibrating piece (hereinafter referred to as “piezoelectric vibrating piece electrode”) is used as one inner lead of an airtight terminal. The other inner lead is drawn out in the opposite direction to one end of the sealing tube of the metal cylindrical bottomed cylindrical body to form a pair of terminals.

In downsizing the piezoelectric vibrator, the components that connect the piezoelectric vibrating piece electrode have an important influence on the airtightness, frequency, impact resistance, and CI value characteristics of the piezoelectric vibrator. The component member of Patent Document 2 that connects the other piezoelectric vibrating piece electrode to one end of the sealing tube is provided with a lead terminal that connects to the piezoelectric vibrating piece electrode through a small hole in the sealing tube. The component member of Patent Document 3 that connects the other piezoelectric vibrating reed electrode to one end of the sealing tube is provided with a protruding piece inside the metal shell provided in the base. The lead terminal of the airtight terminal and one end of the sealing tube are connected to the surface mounting terminal connected to the external substrate.
JP 2000-165182 A Japanese Patent Laid-Open No. 03-171915 Japanese Patent Laid-Open No. 2002-43886

  However, as a configuration for connecting the piezoelectric vibrating piece in Patent Document 2 to one end of the sealing tube, a configuration in which a lead terminal connected to the piezoelectric vibrating piece electrode through a small hole in the sealing tube has the following problems. ing.

The piezoelectric vibrator disclosed in Patent Document 2 is
1) The piezoelectric vibrating piece is limited to a piezoelectric vibrating piece having a strength and a size capable of supporting the piezoelectric vibrating piece independently by being opposed to both ends of the piezoelectric vibrating piece. The width is about 0.45 mm to 0.55 mm and the thickness is about 100 μm. A small piezoelectric vibrating piece does not have a strength capable of supporting both ends independently, and it is difficult to achieve a miniaturized structure that can be housed in a small-diameter cylindrical metal case.

2) In addition to the press-fit part of the airtight terminal part and the cylindrical metal case, there are three airtightly attached parts of the lead terminal small hole part of the cylindrical metal case. It does not take advantage of its high airtightness as a package and lacks airtight reliability.
There is a problem.

  Moreover, as a structure connected to the end of the sealing pipe | tube in patent document 3, it has the following subjects that it is the structure which provides the protrusion piece inside the metal shell which it had in the base.

The piezoelectric vibrator disclosed in Patent Document 3 is
1) Since the piezoelectric vibrating reed is mounted on the tangent line of one lead terminal disposed at the center of the sealing tube, the structure is similar to the conventional structure in which two lead terminals are disposed at the center of the sealing tube. There is no distance between the piezoelectric vibrating piece and the inner wall of the sealing tube, and the piezoelectric vibrating piece interferes with the inner wall of the sealing tube to seal the piezoelectric vibrating piece having a width of about 0.45 mm to 0.55 mm and a thickness of about 100 μm. Storage in the tube becomes difficult.

  Avoiding this, even if the lead terminal has a small diameter or the lead terminal is eccentric, similarly, when inserting the tablet into the eccentric hole and eccentric position, which is an insulating material in the hermetic terminal sealing assembly, or plating the lead terminal The lead terminal is easily bent during processing, the lead terminal lacks the required rigidity, and the vibrator quality characteristics may deteriorate due to the handling of the piezoelectric vibrator as well as the mounting accuracy of the piezoelectric vibrator. There was a problem that it was obstructing.

  2) In order to make a stable mount electrode connection, the projecting piece inside the metal shell as a component for connecting the piezoelectric vibrating piece electrode needs to regulate the rotation direction of the metal shell for connection. Variations in the metal shell rotation direction regulation may cause variations in the location and connection area of the mount electrode connection, which may lead to a decrease in vibrator quality characteristics.

  3) Since the lead terminal and the protruding piece are opposed to each other with a predetermined interval, and the piezoelectric vibrating piece is mounted at this interval and mounted, the electric connection between the protruding piece inside the metal shell and the piezoelectric vibrating piece electrode Is limited to means such as a conductive adhesive that fills the gap between the protruding pieces, and has the disadvantage that the gas from the conductive adhesive lowers the degree of vacuum and reduces the CI value characteristics when sealed. is doing.

  Next, in the conventional surface mount piezoelectric vibrator 10 described above, since the electrode terminal 11 is formed in a crank shape, the lower electrode terminal 11a protrudes outward from the outer lead 3, and the surface mount piezoelectric vibration is formed. There is a problem that the length of the child 10 is required up to the size of the lower electrode terminal 11a and the tip of the outer lead 3, which hinders the miniaturization of the surface mount type piezoelectric vibrator 10.

  Further, the electrode terminal 11 on the sealing tube 5 side has the vertical portion 11b arranged in series in the longitudinal direction of the surface-mount type piezoelectric vibrator 10, and therefore requires a length including the vertical portion 11b. There is a problem that the piezoelectric vibrator 10 is hindered from being reduced in size and mounting area.

  The present invention solves the above-described problems, maintains high airtightness, provides a smaller-sized cylinder-type package piezoelectric vibrator, and has a height of 0.9 mm or less by mounting the piezoelectric vibrator. An object of the present invention is to provide a small surface-mount piezoelectric vibrator that can easily reduce the mounting area.

  In order to achieve the above object, the present invention takes the following solutions.

  The piezoelectric vibrator of the first invention is supported by an airtight terminal sealed with one lead terminal penetrating through an insulating material filled in a metal ring, and an inner lead of the lead terminal, A piezoelectric vibrating piece having two excitation electrodes and two mounting electrodes, and a metal bottomed cylindrical shape that houses the piezoelectric vibrating piece and has an opening hermetically sealed with the metal ring of the hermetic terminal The lead terminal has a circular cross-sectional shape and is disposed at the center position of the metal ring, and the inner lead is an axial center line of the metal ring. Parallel to the center line and at a predetermined distance from the center line, and the piezoelectric vibrating piece is supported by the flat step surface so as to be parallel to a substantially central position of the sealing tube. It is characterized by being.

  According to the configuration of the first aspect of the invention, the diameter of the metal ring and the sealing tube is the smallest, the piezoelectric vibrating reed mounting accuracy to be accommodated in the sealing tube is high, and the piezoelectric vibrating reed can be mounted despite the miniaturization. It is possible to provide a small piezoelectric vibrator that maintains the rigidity of the lead terminals to be supported and eliminates a short circuit due to the proximity of two conventional lead terminals.

  That is, the lead terminal has a circular cross-sectional shape and is arranged at the center position of the metal ring, and the piezoelectric vibrating piece is supported by a flat step surface so as to be parallel to the approximate center position of the sealing tube. Thus, a small, highly airtight cylindrical piezoelectric vibrator having the smallest diameter of the metal ring and the sealing tube can be obtained.

  Further, since the lead terminal has a single circular cross-sectional shape and is arranged at the center position of the metal ring, the lead terminal center position can be most easily made into an airtight terminal with high precision arrangement. Further, it is possible to easily form and form the inner lead parallel flat stepped surface with high accuracy based on the highly accurate lead terminal center position reference. Since the inner lead parallel flat stepped surface can be formed with high precision, the piezoelectric vibrating piece is stably mounted on the parallel flat stepped surface, and is optimally parallel to the approximate center position of the maximum diameter of the sealing tube that houses the piezoelectric vibrating piece. It is possible to provide a small piezoelectric vibrator that is arranged and adapted to the minimum inner diameter of the sealing tube.

  In addition, the center position of one lead terminal allows a thicker lead terminal diameter to be placed at the center position of the metal ring compared to two lead terminals. A piezoelectric vibrator that maintains the rigidity of the terminal can be obtained.

  Further, the arrangement error of the two lead terminals which causes the mounting accuracy of the piezoelectric vibrating piece and the short circuit due to the proximity of the two lead terminals can be solved by the arrangement of the one lead terminal.

  According to a second aspect of the invention, in the configuration of the first aspect of the invention, the two mount electrodes of the piezoelectric vibrating piece are each formed on the front and back surfaces of the mount portion supported by the inner lead. It is characterized by.

  According to the configuration of the second aspect of the invention, the two mounting electrodes of the piezoelectric vibrating piece are formed on the front and back surfaces of the mounting portion supported by the inner lead portion, respectively, thereby accommodating the piezoelectric vibrating piece. Optimal arrangement parallel to the approximate center position of the maximum diameter of the sealing tube, suitable for support by a single inner lead terminal, and front-back direction connection configuration at approximately the center position of the piezoelectric vibrating piece electrode. Therefore, it is possible to provide a piezoelectric vibrator having a hermetic terminal in which the surface of the mount electrode to be taken is wide, which is small in size, and prevents a short circuit between the mount electrodes.

  According to a third aspect of the present invention, in the piezoelectric vibrator according to the first or second aspect, the metal ring has a small-diameter portion parallel to the center line of the metal ring on the inner lead side. Of the mount electrodes, the first mount electrode is connected to the flat stepped surface of the inner lead, and the second mount electrode is connected to the small diameter portion.

  According to the configuration of the third aspect of the invention, the first mount electrode is connected to the flat step surface of the inner lead, and the second mount electrode is connected to the small diameter portion parallel to the center line of the metal ring. As a result, a small size and stable connection quality can be obtained.

  That is, the small-diameter portion spans in the circumferential direction between the sealing tube and the metal ring, creates a space that eliminates the need for circumferential connection positioning directionality, and provides electrode connection means having freedom in the circumferential direction. By being able to take it, stable connection quality can be obtained, and the front and back direction connection of the mount electrode at a substantially central position of the piezoelectric vibrating piece can be configured in a small size.

  According to a fourth aspect of the invention, in the piezoelectric vibrator according to any one of the first to third aspects of the invention, the second mount electrode and the small diameter portion are connected by a metal wire. It is characterized by.

  According to the configuration of the fourth aspect of the invention, the connection with the mount electrode connected with the metal wire to the small diameter portion parallel to the center line of the metal ring is a distance away from the mount electrode at the substantially central position of the piezoelectric vibrating piece. It is suitable for the connection with the metal ring in.

  By connecting with a metal wire, the reliability of the connection is ensured by following the minute relative displacement of the piezoelectric vibrating piece, and there is an adverse effect on the quality of outgassing during baking due to the use of an adhesive or the like for the connection. An avoiding piezoelectric vibrator can be provided.

  According to a fifth aspect of the present invention, in the piezoelectric vibrator according to any one of the first to fourth aspects of the invention, the flat stepped surface exceeds the position of the center line of the metal ring, and the center of the metal ring. It is preferable that the distance is not more than the distance of the thickness of the piezoelectric vibrating piece from the line.

  According to such a preferable configuration, the flat step surface exceeds the position of the center line of the metal ring and is equal to or less than the distance of the thickness of the piezoelectric vibrating piece from the center line of the metal ring, so that the flat step surface of the inner lead is sealed. It is possible to provide a small piezoelectric vibrator that is arranged in parallel at a substantially central position of the pipe and that makes the best use of the sealed pipe space.

  In other words, the thickness of the piezoelectric vibrating piece with respect to the center of the metal ring at the position of the maximum diameter of the sealing tube has a parallel flat step surface that stabilizes the mounting of the piezoelectric vibrating piece in the substantially central space of the sealing tube. A small piezoelectric vibrator having a sealed tube with a minimum diameter at a substantially central position within the range and in parallel can be obtained.

  According to a sixth aspect of the present invention, in the piezoelectric vibrator according to any one of the first to fifth aspects, the diameter of the lead terminal is 25% or more of the innermost inner diameter of the metal ring, and 40 % Or less is preferable.

  According to such a preferable configuration, the lead terminal has a diameter of 25% or more of the innermost inner diameter of the metal ring and 40% or less, so that the rigidity of the lead terminal can be increased despite the miniaturization of the metal ring. It is possible to provide a small piezoelectric vibrator having impact resistance while maintaining the rigidity of two or more.

  The diameter of the lead terminal is 25% or more of the innermost diameter of the metal ring and 40% or less. When the lead terminal has a diameter of 25% or less of the inner diameter of the metal ring, the rigidity of the lead terminal is reduced and the impact resistance is weak. If it is 40% or more, it is difficult to form a tablet of the insulating material.

  According to a seventh aspect of the present invention, in the piezoelectric vibrator according to any one of the first to sixth aspects, the thickness of the flat stepped surface is 60% or more of the diameter of the lead terminal, and 70 % Or less is preferable.

  According to such a preferable configuration, the thickness of the flat stepped surface is 60% or more and 70% or less of the diameter of the lead terminal, so that the rigidity of the lead terminal can be improved despite the miniaturization of the metal ring. Compact size that combines shock resistance with two or more stiff rigidity and stable mounting of the piezoelectric vibrating piece at a substantially central position on a parallel flat stepped surface with a wider support width. A piezoelectric vibrator having an airtight terminal can be provided.

  According to an eighth aspect of the present invention, in the piezoelectric vibrator according to any one of the first to seventh aspects, the length of the small diameter portion is 0.05 mm or more and 0.15 mm or less. Is preferred.

  According to such a preferable configuration, the length of the small diameter portion is 0.05 mm or more and 0.15 mm or less, so that the small diameter portion extends in the circumferential direction between the sealing tube and the metal ring. Further, it is possible to ensure the length necessary for electrode connection without the need for circumferential connection positioning. A small piezoelectric vibrator that is suitable for satisfying the length of approaching the capillary of a wire bonder connected by a metal wire and having a shortened metal ring length direction can be provided.

  According to a ninth aspect of the present invention, in the piezoelectric vibrator according to any one of the first to eighth aspects, the outer diameter of the sealing tube is preferably 0.8 mm or less.

  According to such a preferable configuration, the lead terminal that supports the piezoelectric vibrating piece despite the fact that the diameter of the metal ring and the sealing tube is the smallest, the mounting accuracy of the piezoelectric vibrating piece housed in the sealing tube is high, and the size is reduced. Therefore, it is possible to provide a miniaturized piezoelectric vibrator that can be accommodated within φ0.8 mm of a cylindrical cylinder-type package piezoelectric vibrator by eliminating the short-circuit caused by the approach of two conventional lead terminals.

  According to a tenth aspect of the present invention, there is provided a surface-mount piezoelectric vibrator for electrically connecting the piezoelectric vibrator according to any one of the first to ninth inventions and the piezoelectric vibrator to the outside. The electrode terminal and a mold resin for covering the piezoelectric vibrator are provided.

  According to the configuration of the tenth invention, the piezoelectric vibrator according to any one of the first to ninth inventions, and an electrode terminal for establishing electrical continuity between the piezoelectric vibrator and the outside And a mold resin that covers the piezoelectric vibrator, and a cylindrical surface-mount type piezoelectric vibrator having a cylindrical shape with a diameter of φ0.8 mm or less is accommodated and the thickness is reduced. be able to.

  In other words, the diameter of the metal ring and the sealing tube is the smallest, the mounting accuracy of the piezoelectric vibrating piece housed in the sealing tube is high, and the rigidity of the lead terminal that supports the piezoelectric vibrating piece is maintained despite the miniaturization. In addition, by having a small piezoelectric vibrator that eliminates the short-circuit due to the approach of two conventional lead terminals, the piezoelectric vibrator of a cylindrical cylinder package with a high airtightness of φ0.8 mm or less is housed in the mold resin, A thin surface-mount piezoelectric vibrator having a reduced height can be provided.

  According to an eleventh aspect of the invention, in the structure of the tenth aspect, the surface mount type piezoelectric vibrator includes: a horizontal portion that is disposed at both ends in the longitudinal direction of the piezoelectric vibrator and is connected to an external electrode of the electrode terminal; The electrode terminal is formed by a vertical portion where a part of the electrode terminal is bent and raised.

  According to the configuration of the eleventh aspect of the invention, the electrode terminal is formed by a horizontal portion that is disposed at both ends in the longitudinal direction of the piezoelectric vibrator and is electrically connected to the outside, and a vertical portion in which a part of the electrode terminal is bent up. As a result, it is possible to provide a small surface-mount type piezoelectric vibrator that can reduce the mounting area as a minimum configuration while suppressing the length.

  That is, a horizontal part electrically connected to the outside, a horizontal part that is bent in a crank shape by a position part in the width direction of the sealing tube, and a vertical part that serves as an anchor of a mold resin covering the piezoelectric vibrator A small surface-mount type piezoelectric vibrator that does not have a long space such as a portion and can be reduced in length and the mounting area can be reduced as a minimum configuration.

  In a twelfth aspect of the invention according to the tenth or eleventh aspect of the invention, a vertical portion of the electrode terminal on the airtight terminal side is orthogonal to a longitudinal direction of the surface-mount piezoelectric vibrator, and is on the sealing tube side. The vertical part of the electrode terminal is parallel to the longitudinal direction of the surface-mount piezoelectric vibrator.

  According to the configuration of this twelfth aspect, the vertical portion of the electrode terminal on the airtight terminal side is orthogonal to the longitudinal direction of the surface mount piezoelectric vibrator, and the vertical portion of the electrode terminal on the sealing tube side is the surface mount type. By being parallel to the longitudinal direction of the piezoelectric vibrator, it is possible to provide a small surface-mount piezoelectric vibrator that can suppress the length without increasing the external dimensions and can reduce the mounting area as a minimum configuration.

  That is, the vertical portion of the electrode terminal on the airtight terminal side is orthogonal to the longitudinal direction of the surface-mount piezoelectric vibrator, so that only the thickness of the vertical portion of the electrode terminal is present in the longitudinal direction of the surface-mount piezoelectric vibrator. And the vertical part of the electrode terminal on the sealing tube side is parallel to the longitudinal direction of the surface mount piezoelectric vibrator, so that there is no increase in dimension in the longitudinal direction of the surface mount piezoelectric vibrator. Thus, a small surface-mount piezoelectric vibrator in which the total length of the surface-mount piezoelectric vibrator is shortened can be obtained.

  According to a thirteenth aspect of the present invention, in the configuration of any one of the tenth to twelfth aspects of the invention, the electrode terminal is connected to the lead terminal at the vertical portion on the airtight terminal side, and the sealing tube side It is characterized by connecting with the said sealing pipe to the said horizontal part.

  According to the configuration of the thirteenth invention, the electrode terminal is connected to the lead terminal at the vertical portion of the electrode terminal on the airtight terminal side, and is connected to the sealing tube at the horizontal portion of the electrode terminal on the sealing tube side. This provides a surface-mount type piezoelectric vibrator that has a stable connection structure by contact connection from above and below, and that takes out the terminals to the outside of the mold resin that covers the connection terminals with a minimum configuration without the need for other connection members can do.

  According to a fourteenth aspect of the invention, in the configuration of any one of the tenth to thirteenth aspects of the invention, the electrode terminal on the airtight terminal side has the vertical portion at the center in the longitudinal direction of the surface mount piezoelectric vibrator. The surface mounting type piezoelectric vibrator has a notch with respect to the sealing tube at the center in the longitudinal direction.

  According to the structure of the fourteenth aspect of the invention, the electrode terminal on the airtight terminal side bends the vertical portion from the center portion on the outer side in the longitudinal direction of the surface mount type piezoelectric vibrator, thereby increasing the length of the surface mount type piezoelectric vibrator. A surface-mount piezoelectric vibrator that is short and has a low height can be provided.

  That is, the vertical portion of the electrode terminal on the sealing tube side is parallel to the longitudinal direction of the surface-mount piezoelectric vibrator, so that there is no increase in dimension in the longitudinal direction of the surface-mount piezoelectric vibrator. By providing a notch at the lower position of the bulging portion of the portion, the height position of the surface-mount type piezoelectric vibrator can be suppressed by lowering the height position of the sealing tube opening.

  According to a fifteenth aspect of the invention, in the configuration of any one of the tenth to fourteenth aspects of the invention, the electrode terminal on the sealing tube side is arranged on the inner side in the longitudinal direction of the surface mount piezoelectric vibrator. The surface mount type piezoelectric vibrator is bent from the outside in parallel with the longitudinal direction, and vertical portions that can be supported on both side surfaces of the sealing tube are formed.

  According to the configuration of the fifteenth aspect of the invention, the electrode terminal on the sealing tube side is bent and raised from the outside in the longitudinal direction inner portion of the surface mount piezoelectric vibrator in parallel with the longitudinal direction of the surface mount piezoelectric vibrator. By forming vertical parts that can be supported on both sides of the sealing tube, the length of the surface-mount type piezoelectric vibrator is shortened, and the position of the piezoelectric vibrator is stably stabilized in the mold resin to be coated. It is possible to provide a surface-mount type piezoelectric vibrator to be housed.

  That is, the electrode terminal vertical part on the sealing tube side is not arranged in the longitudinal direction of the surface-mount piezoelectric vibrator, but is arranged in parallel with the longitudinal direction of the surface-mount piezoelectric vibrator. The total length of the child can be shortened. In addition, the width of the surface mount type piezoelectric vibrator of the sealing tube is formed by bending up from the outside in parallel with the longitudinal direction of the surface mount type piezoelectric vibrator and forming vertical parts that can be supported on both sides of the seal tube. It is possible to stably store in the resin mold part in terms of quality without regulating the position in the direction and shifting in the lateral direction and without exposing the resin mold part to the side surface after molding.

  In addition, since the position of the sealing tube is stably regulated, positioning pins from the outer part are not required, and conventionally there are exposed parts by positioning pins from the outer part of the surface mount type piezoelectric vibrator. The periphery of the surface-mounted piezoelectric vibrator is not properly covered with the resin material, and it is possible to eliminate the partial exposure of the sealing pipe of the piezoelectric vibrator from the resin mold portion.

  According to a sixteenth aspect of the present invention, in the configuration of any one of the tenth to fifteenth inventions, the thickness of the electrode terminal is preferably 0.1 mm or less.

  According to such a preferable configuration, a surface-mount type piezoelectric vibrator capable of a height of 0.9 mm or less can be provided when the electrode terminal has a thickness of 0.1 mm or less.

  In other words, when the piezoelectric vibrator and the electrode terminal connected to the external electrode are overlapped with each other, it is easy to obtain a stable connection by connecting in the vertical direction. Contributing to the thinning of surface mount piezoelectric vibrators with a height of 0.9 mm or less, including the thickness of the vibrator and electrode terminals connected to external electrodes of 0.1 mm or less, It is possible to provide a surface-mount type piezoelectric vibrator having a height that has not been conventionally achieved.

  According to a seventeenth aspect of the present invention, there is provided the surface mount piezoelectric vibrator according to any one of the tenth to sixteenth aspects, wherein the height of the surface mount piezoelectric vibrator is 0.9 mm or less. Is preferred.

  According to such a preferable configuration, when the electrode terminal connected to the piezoelectric vibrator and the external electrode is overlapped, and the structure is such that a stable connection by vertical connection is easily obtained, a cylindrical shape that can be accommodated within φ0.8 mm or less. Contributes to the miniaturization of surface mount piezoelectric vibrators that can achieve a height of 0.9 mm or less, including the thickness of the piezoelectric vibrators in the cylinder package and electrode terminals connected to external electrodes that are 0.1 mm or less. Therefore, it is possible to provide a surface-mounting type piezoelectric vibrator of a thin cylindrical cylinder type package that suppresses a small height that could not be realized conventionally.

  As described above, according to the present invention, it is possible to provide a piezoelectric vibrator having a smaller cylinder type package while maintaining high airtightness, and by mounting the piezoelectric vibrator, the height is 0.9 mm. In the following, it is possible to provide a small surface-mount type piezoelectric vibrator whose mounting area can be easily reduced.

Specific embodiments suitable for the piezoelectric vibrator according to the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is a perspective view showing the overall appearance of the piezoelectric vibrator according to the present embodiment, FIG. 2 is a perspective view of the internal structure of the piezoelectric vibrator, and FIG. A perspective view is shown, FIG. 4B is a sectional perspective view of the hermetic terminal, and FIG. 4 is a perspective view of an electrode structure of the piezoelectric vibrating piece.

  As shown in FIG. 1, the piezoelectric vibrator 20 according to the present embodiment is a cylinder-type package having a metal bottomed cylindrical sealing tube 21, and an airtight terminal is provided in an opening 26 of the sealing tube 21. 22 is press-fitted, and one lead terminal 23 projects from the center of the airtight terminal 22 to the outside.

  As shown in FIG. 2, the piezoelectric vibrator 20 includes a piezoelectric vibration supported by an airtight terminal 22 sealed with one lead terminal 23 penetrating into the metal ring 24 and an inner lead 23 a of the lead terminal 23. The piece 25 and the piezoelectric vibrating piece 25 are housed, and the opening 26 is composed of a metal bottomed cylindrical sealing tube 21 hermetically sealed with a metal ring 24 of the hermetic terminal 22.

  As shown in FIG. 3A, the hermetic terminal 22 includes a metal ring 24 made of Kovar, 42 alloy, etc., a sealing glass 27 as an insulating material filled inside the metal ring 24, and this sealing It is composed of a single lead terminal 23 that penetrates and is fixed inside the metal ring 24 by glass 27. One lead terminal 23 and the metal ring 24 are electrically insulated from each other. The metal ring 24 has a small diameter portion 28 having a predetermined length parallel to the center line of the metal ring 24 on the inner lead 23a side.

  As shown in FIG. 3B, one lead terminal 23 has a circular cross-sectional shape and is arranged at the center position of the metal ring 24. One side protruding outward from the airtight terminal 22 is the outer lead 23b, and the portion extending inwardly housing the piezoelectric vibrating piece 25 is the inner lead 23a. The inner lead 23a penetrates through the airtight terminal 22 to become an outer lead 23b. The inner lead 23a and the outer lead 23b are collectively referred to as a lead terminal 23. The inner lead 23a has a flat stepped surface 30 that is parallel to the axial center line of the metal ring 24 and spaced a predetermined distance from the center line. Since the lead terminals 23 are arranged from the conventional two to one, the relative ratio to the inner diameter of the metal ring 24 is larger than the relative ratio in the case of the diameter of the conventional lead terminal, and the lead terminals 23 are thick. Is arranged. Therefore, the flat step surface 30 is formed with a large width.

  This lead terminal 23 is formed by forming a steel plating layer with a film thickness of about 6 μm or less as a base layer on a metal surface such as Kovar or 42 alloy, and plating the surface with a high melting point solder with a film thickness of about 22 μm or less. It is.

The sealing glass 27 is made of Kovar glass having a thermal expansion coefficient of about 4 × 10 ⁻⁶ / ° C. to about 6 × 10 ⁻⁶ / ° C. and close to Kovar, and is sealed between the metal ring 24 and the lead terminal 23. Electrical insulation and airtightness are maintained.

  As shown in FIG. 4, the piezoelectric vibrating piece 25 is made of a piezoelectric material such as quartz, and is formed in a tuning fork shape by photolithography. Two excitation electrodes 31 and two mount electrodes 32 are formed on the surface of the tuning-fork type piezoelectric vibrating piece 25. Two excitation electrodes 31 are formed on the surface of the two vibrating arms, and one mount electrode 32 connected to the excitation electrode 31 is formed on the front and back surfaces of the base of the piezoelectric vibrating piece 25. Here, the electrode on the front surface is called the first mount electrode 32a, and the electrode on the back surface is called the second mount electrode 32b. Since one mount electrode 32 of this embodiment is formed on each of the front and back surfaces of the piezoelectric vibrating piece 25, the piezoelectric vibrating piece is downsized compared to the conventional mount electrode formed adjacent to the same surface. This is suitable for a connection configuration for preventing a short-circuit between the 25 mount electrodes 32.

  FIG. 5 is a front sectional view of the piezoelectric vibrator of the present embodiment, and FIG. 6 is a side sectional view of the piezoelectric vibrator.

  As shown in FIG. 5, the first mount electrode 32a of the piezoelectric vibrating piece 25 is connected to the flat step surface 30 of the inner lead 23a with solder or the like, and the piezoelectric vibrating piece 25 is supported. The piezoelectric vibrating piece 25 is supported on the flat stepped surface 30 of the inner lead 23a, so that the piezoelectric vibrating piece 25 is held parallel to the axial center line of the metal ring 24 and at a predetermined distance from the center line. Yes. The second mount electrode 32b of the piezoelectric vibrating piece 25 is connected to the small diameter portion 28 of the metal ring 24 by a metal wire 33 such as aluminum or gold wire.

  The sealing tube 21 is composed of a white material whose main composition is copper, zinc, nickel, or 42 alloy composed of about 41% to about 42% nickel and the balance iron, and has a film thickness on the surface. Nickel plating of about 10 μm or less is applied.

  The outer periphery of the metal ring 24 is covered with a sealing tube 21 so as to cover the piezoelectric vibrating piece 25. A piezoelectric vibrating piece 25 is housed inside the sealing tube 21 and hermetically sealed in a vacuum.

  When the metal ring 24 is covered with the opening 26 of the sealing tube 21, a space 29 is formed between the small diameter portion 28 and the metal ring 24, and the space in which the loop shape of the metal wire 33 is accommodated.

  The inner diameter dimension of the opening 26 of the sealing tube 21 is set smaller than the outer diameter dimension of the metal ring 24. When the metal ring 24 is put on the opening 26 of the sealing tube 21, the opening 26 of the sealing tube 21 is caused by the vertical stress corresponding to the difference between the inner diameter of the sealing tube 21 and the outer diameter of the metal ring 24. The metal ring 24 is sealed over the entire circumference, and hermeticity is maintained.

  Next, the electrode connection structure of the piezoelectric vibrator 20 configured as described above will be described. The first mount electrode 32a of the piezoelectric vibrating piece 25 connected to the flat stepped surface 30 of the inner lead 23a is drawn out to one outer lead 23b. A second mount electrode 32 b that is electrically connected to the metal ring 24 and connected by the metal wire 33 is drawn out from the sealing tube 21. That is, the first mount electrode 32 a is drawn to the outer lead 23 b, and the second mount electrode 32 b is drawn to the sealing tube 21. When a predetermined AC voltage is applied as a drive voltage between the outer lead 23b and the sealing tube 21 thus connected to each other, the current is supplied to the first mount electrode 32a from the inner lead 23a, the metal ring 24, and the metal It flows to the excitation electrode 31 through the second mount electrode 32b from the wire 33, and the piezoelectric vibrating piece 25 oscillates at a predetermined frequency by the piezoelectric action.

  In the piezoelectric vibrator 20 of the present embodiment, as shown in FIG. 5, the flat stepped surface 30 formed of the side wall of the inner lead 23 a exceeds the position of the center line of the metal ring 24 and the piezoelectric vibration from the center line of the metal ring 24. It is formed at a position equal to or less than the distance of the thickness of the piece 4, and is disposed at a substantially central position of the sealing tube 21 and in parallel. For this reason, the piezoelectric vibrating reed 25 is different from the conventional structure in which the piezoelectric vibrating reed 4 joined on the tangent line of the inner lead 2 shown in FIG. It is supported by a flat step surface 30 so as to be substantially in the center and parallel.

  Thus, the diameters of the metal ring 24 and the sealing tube 21 are the smallest. At the same time, the lead terminal 23 is arranged at the center position of the metal ring 24, which makes it easy to place the lead terminal 23 at the center position with high accuracy. In addition, since the flat stepped surface 30 of the inner lead 23a can be easily formed in parallel with high precision with respect to the center position of the lead terminal 23 with high precision, the piezoelectric vibrating reed 25 is substantially at the center of the sealing tube 21. It is stably mounted at the optimal position parallel to the position.

  Further, by arranging one lead terminal 23 at the center position, the thick lead terminal 23 can be arranged at the center position of the metal ring 24 as compared with the conventional arrangement of two lead terminals. The piezoelectric vibrator 20 maintains the rigidity of the lead terminal 23 in spite of the downsizing of the 24. In addition, the placement error of the two conventional lead terminals which causes the mounting accuracy of the piezoelectric vibrating piece 25 and the short circuit due to the proximity of the two conventional lead terminals are eliminated by the placement of one lead terminal 23 and the front and rear surface mount electrode connection. Has been.

  The small-diameter portion 28 connected to the second mount electrode 32b by the metal wire 33 extends in the circumferential direction between the sealing tube 21 and the metal ring 24, and eliminates the need for circumferential connection positioning directionality. 29 is made. Since this space 29 can be taken by electrode connecting means having a degree of freedom in the circumferential direction, stable connection quality can be obtained. In addition, a small configuration is achieved by connecting the mount electrodes of the piezoelectric vibrating piece 25 in the front-back direction without requiring other members.

  The second mount electrode 32 b is connected to the small diameter portion 28 parallel to the center line of the metal ring 24 by a metal wire 33. A metal wire is suitable for connection between the mount electrode 32 of the piezoelectric vibrating piece 25 and the metal ring 24 at a distance. The connection with the metal wire 33 follows the minute relative displacement at the base of the piezoelectric vibrating piece 25 at the time of impact to ensure the reliability of the connection, and outgas at the time of baking by using an adhesive or the like for the connection. It is suitable for avoiding the quality adverse effects of the occurrence.

  Next, the distance L1 from the center line of the metal ring 24 to the flat stepped surface 30 shown in FIG. 5 is equal to or less than the thickness T1 of the piezoelectric vibrating piece 25. The flat step surface 30 is located within the range of the thickness T <b> 1 of the piezoelectric vibrating piece 25 from the center line of the metal ring 24. A piezoelectric vibrating piece 25 is disposed on a surface parallel to the axial center line of the metal ring 24. In the piezoelectric vibrating piece 25, the metal ring 24 is put on the opening 26 of the sealing tube 21, and the axial center line of the sealing tube 21 and the metal ring 24 is in parallel with each other. Will be placed. Thereby, the piezoelectric vibrating piece 25 is made parallel to the center of the metal ring 24 at the position of the maximum diameter of the sealing tube 21 within the thickness range of the piezoelectric vibrating piece 25, and the space of the sealing tube 21 is utilized to the maximum. Therefore, the sealing tube 21 having the minimum diameter can be obtained. The distance L1 from the center line of the metal ring 24 to the flat stepped surface 30 is preferably ½ of the thickness T1 of the piezoelectric vibrating piece 25 where the piezoelectric vibrating piece 25 is at the center position of the sealing tube 21.

  The diameter D1 of the lead terminal 23 is 25% or more of the innermost diameter D2 of the metal ring 24 and 40% or less. A lead terminal 23 having a large wire diameter, which could not be inserted in the conventional structure of two lead terminals, is arranged. Therefore, as the metal ring 24 is reduced in size, the lead terminal 23 is also reduced in diameter to prevent rigidity and impact resistance from being weakened, and the rigidity of the lead terminal 23 is maintained to be equal to or more than that of two conventional lead terminals. The inner lead 23a is formed. The diameter D1 of the lead terminal 23 is 25% or more of the innermost diameter D2 of the metal ring 24 and 40% or less. When the diameter D1 is 25% or less of the innermost diameter D2 of the metal ring 24, there is no rigidity and impact resistance. This is because the properties are weakened, and if it is 40% or more, the glass sealing quality is deteriorated.

  As shown in FIG. 6, the thickness T <b> 2 of the flat stepped surface 30 is 60% or more and 70% or less of the diameter D <b> 1 of the lead terminal 23. By forming the flat stepped surface 30, the length L2 of the stepped portion 34 is as large as 120 to 160% of the diameter D1 of the lead terminal 23. The thickness T2 of 60 to 70% of the diameter D1 of the lead terminal 23 maintains the rigidity equal to or more than that of two conventional lead terminals, and the width L2 of the stepped portion 34 is the support on which the piezoelectric vibrating piece 25 is mounted. With the effect of widening the width, it is suitable for obtaining impact resistance and stable mount quality.

  The diameter D3 of the small diameter portion 28 is smaller than the outer diameter D4 of the metal ring 24 and larger than the innermost diameter D2 of the metal ring 24, so that the circumference between the metal ring 24 on the inner lead 23a side and the sealing tube 21 is the circumference. A space 29 is formed across the direction. The length L3 of the diameter D3 of the small diameter portion 28 from the inner lead 23a side is 0.05 mm or more and 0.20 mm or less. The length L3 of the diameter D3 of the small-diameter portion 28 ensures a necessary length to allow a tool such as a capillary of a wire bonder connected by the metal wire 33 to approach, and eliminates the need for circumferential connection positioning directionality and sealing. It is suitable for satisfying the length of connection with the space 29 between the tube 21 and obtaining a stable quality of electrode connection. Further, the length L2 of the small diameter portion 28 is suitable for shortening the length of the piezoelectric vibrator 20 by minimizing the length of the metal ring 24.

  The outer diameter D5 of the sealing tube 21 is preferably 0.8 mm or less. When the outer diameter D5 is larger than 0.8 mm, the arrangement error of the two conventional lead terminals which causes the mounting accuracy of the piezoelectric vibrating piece 25 and the short circuit due to the close proximity of the two conventional lead terminals are prevented. In particular, there is no great difficulty and there is no advantage of adopting such a structure.

  Here, the dimensions of each part of the piezoelectric vibrator 20 shown as an example of the present embodiment are as follows.

  The outer diameter D5 of the sealing tube 21 is 0.75 mm. The length L0 is 3.15 mm, and the diameter D1 of the lead terminal 23 is 0.2 mm. The innermost diameter D2 of the metal ring 24 is 0.4 mm. The flat stepped surface 30 has a thickness T2 of 0.13 mm. The thickness T1 of the piezoelectric vibrating piece 25 is 0.1 mm. The length L2 of the step portion 34 is 0.21 mm. The length L3 of the diameter D3 of the small diameter portion is 0.1 mm. Due to the dimensions, the piezoelectric vibrator 20 is small.

  The piezoelectric vibrator 20 of the present embodiment is configured as described above, and the diameters of the metal ring 24 and the sealing tube 21 are minimized. Despite such miniaturization, the mounting accuracy of the piezoelectric vibrating reed 25 accommodated in the sealing tube 21 is maintained with high accuracy, and the rigidity of the lead terminal 23 that supports the piezoelectric vibrating reed 25 is maintained. A short cylindrical cylinder-type package piezoelectric vibrator 20 that eliminates short-circuiting due to the approach of two lead terminals and can be accommodated in φ0.8 mm or less can be provided.

  Hereinafter, specific embodiments suitable for the surface-mounted piezoelectric vibrator according to the present invention will be described in detail with reference to the drawings.

  7A and 7B show the structure of the surface-mount piezoelectric vibrator according to the present embodiment. FIG. 7A is an overall perspective view, and FIG. 7B is a perspective view of the internal structure. 8 shows an exploded perspective view of the configuration of FIG. 7, (a) shows a cylinder type package piezoelectric vibrator, (b) shows an electrode terminal on the airtight terminal side, and (c) shows a sealing An electrode terminal on the tube side is shown, and (d) shows a mold resin.

  As shown in FIGS. 7A and 7B, the surface mounted piezoelectric vibrator 40 according to the present embodiment has the piezoelectric vibrator 20 disposed at the center. The outer shape of the piezoelectric vibrator 20 is covered with a mold resin 41. In the electrode terminal 42, horizontal portions 42 aa and 42 ba of the electrode terminal, which is a part of the electrode terminal 42, are exposed on the bottom surface of the surface-mounted piezoelectric vibrator 40.

  As shown in FIG. 8, the surface-mount piezoelectric vibrator 40 is for electrically connecting the piezoelectric vibrator 20 of FIG. 8A in the first embodiment described above with the piezoelectric vibrator 20 and the outside. 8B and 8C, and the mold resin 41 shown in FIG. 8D covering the piezoelectric vibrator 20.

  As shown in these drawings, the surface mount type piezoelectric vibrator 40 has the piezoelectric vibrator 20 disposed at the center thereof. The outer shape of the piezoelectric vibrator 20 is formed into a cylindrical cylinder, and as shown in FIG. 5 and described above, a predetermined vibration frequency can be generated by applying an AC voltage to the inside thereof. A thin plate-shaped piezoelectric vibrating piece 25 is accommodated. The first mount electrode 32a of the piezoelectric vibrating piece 25 connected to the flat stepped surface 30 of the inner lead 23a is drawn out to one outer lead 23b. A second mount electrode 32 b that is electrically connected to the metal ring 24 and connected by the metal wire 33 is drawn out from the sealing tube 21. When a predetermined alternating voltage is applied as a drive voltage between the outer lead 23 b and the sealing tube 21, the current is a first mount electrode 32 a from the inner lead 23 a, and a second mount from the metal ring 24 and the metal wire 33. It flows to the excitation electrode 31 via the electrode 32b, and the piezoelectric vibrating piece 25 oscillates at a predetermined frequency by the piezoelectric action.

  As shown in FIG. 8, the electrode terminal 42 of this embodiment is composed of an electrode terminal 42a on the airtight terminal side in FIG. 8 (b) and an electrode terminal 42b on the sealing tube side in FIG. 8 (c). Yes. The electrode terminals 42 a and 42 b are disposed at both ends in the longitudinal direction of the piezoelectric vibrator 20. The electrode terminals 42a and 42b are composed of horizontal portions 42aa and 42ba and vertical portions 42ab and 42bb. The electrode terminals 42a and 42b are made of a flat plate material made of a conductive metal such as a copper-based alloy having a plate shape with a thickness of 0.1 mm, for example. The electrode terminals 42a and 42b are formed by pressing the flat plate material, pressing the horizontal portions 42aa and 42ba and the notch 43, and then bending the vertical portions 42ab and 42bb. Yes.

  The vertical portions 42ab and 42bb serve as anchors of the mold resin 41 after being covered with the mold resin 41. Even in the miniaturized surface mount piezoelectric vibrator 40, the molds of the electrode terminals 42a and 42b are molded. The peeling strength from the resin 41 is maintained.

  The horizontal portions 42aa and 42ba are exposed on the outer bottom surface of the mold resin 41 covering the piezoelectric vibrator 20 and connected to the external electrodes. The electrode terminal 42aa on the airtight terminal side and the electrode terminal 42ba on the sealing tube side exposed to the outside from the horizontal end of the mold resin 41 are respectively connected to the outer lead 23b and the sealing tube 21 of the piezoelectric vibrator 20 and the airtight terminal. It is joined at the side joint 44a and the sealing tube side 44b. The joint portion 44a on the airtight terminal side is located at the center of the upper surface of the vertical portion 42ab. The sealing tube side 44b is located on the upper surface of the horizontal portion 42ba between the two vertical portions 42bb. For this reason, the joint portion 44a on the airtight terminal side and the sealing tube side 44b both have a stable connection structure capable of contact connection from above and below. Further, it is configured to be minimal and does not require other connecting members, and is drawn out of the mold resin 41.

  The front ends of the horizontal portions 42aa and 42ba are both divided into two and protrude outward in the horizontal direction of the mold resin 41. Both ends of the horizontal portions 42aa and 42ba are formed in the same shape so that the strength of connection with the external electrode is equal.

  The whole including the piezoelectric vibrator 20 containing the piezoelectric vibrating piece 24 and the electrode terminals 42a and 42b on the airtight terminal side and the sealing tube side is a molding material of a molding resin 41, for example, a resin which is an epoxy molding material or the like. The surface mount type piezoelectric vibrator 40 is formed by molding with a material.

  FIG. 9 shows an enlarged perspective view of the electrode terminal on the airtight terminal side of FIG. As shown in FIG. 9, the electrode terminal 42 a on the hermetic terminal side has a vertical portion 42 ab formed by bending the central portion from the outside in the longitudinal direction of the piezoelectric vibrator 20. The bent vertical part 42ab is formed in the outer shape of the horizontal part 42aa so as to be orthogonal to the longitudinal direction of the piezoelectric vibrator 20 and to the height of the outer lead 23b in the width direction of the piezoelectric vibrator 20. The outer lead 23b is joined to a joint 44a that is an upper part of the vertical part 42ab. Therefore, the length including the outer lead 23b and the joint portion 44a is accommodated in the outer shape of the horizontal portion 42aa. This is because the lower electrode terminal 11a protrudes outward from the outer lead 3 described above, and the surface mounting surface does not have a long space as compared with the conventional structure in which the dimension is increased in the longitudinal direction of the surface mounted piezoelectric vibrator 10 main body. The longitudinal dimension of the mounting type piezoelectric vibrator 40 can be shortened.

  A cutout 43 of the horizontal portion 42aa is provided on the opposite side of the bent vertical portion 42ab. The position of the notch 43 corresponds to a lower position of the enlarged diameter portion of the opening portion 26 of the sealing tube 21, and the electrode terminal 42 aa and the opening portion 26 of the sealing tube 21 have a shape of the notch 43 that does not contact. Due to the presence of the notch 43, the height position of the opening 26 of the sealing tube 21 is lowered, and the height of the surface-mount piezoelectric vibrator 40 is suppressed.

  FIG. 10 shows an enlarged perspective view of the electrode terminal on the sealed tube side of FIG. As shown in FIG. 10, the electrode terminal 42 b on the sealed tube side is bent from both outer sides in the width direction of the piezoelectric vibrator 20 to form a vertical portion 42 bb. The vertical portion 42bb is parallel to the longitudinal direction of the piezoelectric vibrator 20. For this reason, the surface-mounted piezoelectric vibrator 10 is longer than the conventional structure in which the vertical portion 11b is arranged in series in the longitudinal direction of the surface-mounted piezoelectric vibrator 10 shown in FIG. The shortening of the longitudinal dimension of 40 is achieved. Therefore, the size and the mounting area of the surface-mounted piezoelectric vibrator 40 after resin molding can be reduced by shortening the longitudinal dimension.

  The bent vertical portion 42bb is formed in parallel with the sealing tube 21 so as to be supported from both side surfaces of the sealing tube 21. Therefore, the position in the width direction of the sealing tube 21 is stably regulated by the vertical portion 42bb of the electrode terminal 42b. In addition, the vertical direction of the sealing tube 21 and the longitudinal position of the piezoelectric vibrator 20 are stably regulated by the joint portion 44 a with the outer lead 23 b and the joint portion 44 b with the sealing tube 21. As a result, the position in the width direction, the vertical direction position, and the longitudinal direction position of the sealing tube 21 are not shifted, and the mold is stably controlled in terms of position without being exposed to the side surface from the mold resin 41 after molding. It is stored in the resin 41.

  Further, since the electrode terminal 42b on the sealing tube side stably regulates the position of the sealing tube 21, no positioning pin from the outside is required. The conventional surface mount type piezoelectric vibrator 10 shown in FIG. 12 has a depression 12 formed by an external positioning pin, and the periphery of the surface mount type piezoelectric vibrator 10 is not properly covered with a resin material. The sealing tube 5 was partially exposed from the outer shape of the surface mount piezoelectric vibrator 10. On the other hand, in the surface mount piezoelectric vibrator 40 of this embodiment, the periphery is correctly covered with the resin material, and the problem of exposure is solved.

  Here, the outer lead 23b connected to the first mount electrode 32a, which explains the electrode connection structure of the surface mount piezoelectric vibrator 40, is formed on the upper surface of the vertical portion 42ab of the electrode terminal 42a as shown in FIG. It is joined to a certain joint 44a and pulled out to the horizontal part 42aa. The sealing tube 21 connected to the second mount electrode 32b is joined to the joint portion 44b of the horizontal portion 42ba of the electrode terminal 42b, and the mount electrode 32 of the piezoelectric vibrating piece 25 is connected from the lower surface of the horizontal portion of the electrode terminal 42ba. It is pulled out to the external electrode.

  In order to reduce the thickness of the surface mount piezoelectric vibrator 40, the thickness of the electrode terminals 42a and 42b is preferably 0.1 mm or less. Since the thickness of the electrode terminals 42a and 42b is 0.1 mm or less, the height of the surface mount piezoelectric vibrator 40 can be 0.9 mm or less.

  The piezoelectric vibrator 20 and the electrode terminals 42aa and 42ba for establishing electrical continuity between the outside and the electrode terminal 42aa and 42ba are configured to overlap each other, and it is easy to obtain stable connection quality by vertical connection. The structure of the present embodiment is also a structure in which the piezoelectric vibrator 20 and electrode terminals 42aa and 42ba for establishing electrical continuity with the outside are overlapped. The outer diameter of the sealing tube 21 is the largest at the opening 26 that covers the metal ring 24. As described above, the notch 43 is provided in the horizontal portion 42aa of the electrode terminal 42a at the lower portion of the opening 26 having the largest outer diameter of the sealing tube 21, and the notch 43 that does not contact the sealing tube 21 is provided. Since it has a shape, the height of the surface-mount piezoelectric vibrator 40 is not increased even when the electrode terminal 42aa is overlapped. Since the electrode terminal 42b on one sealing tube side is configured to directly overlap the sealing tube 21 and the horizontal portion 42ba of the electrode terminal 42b, the thickness of the electrode terminal 42b remains as it is of the surface mount piezoelectric vibrator 40. It will affect the height. In the present embodiment in which the piezoelectric vibrator 20 and the electrode terminal 42b are stacked, the thickness of the electrode terminal 42aa is set to 0.1 mm or less, whereby the piezoelectric vibrator 20 having a diameter of φ0.8 mm or less and the electrode terminals 42aa and 42ba. The surface-mounted piezoelectric vibrator 40 having a thickness of 0.9 mm or less including the thickness is thinned, and a surface-mounted piezoelectric vibrator 40 having a height that is unprecedented in a cylindrical cylinder package is obtained. ing.

  The piezoelectric vibrator 20 is formed as a surface-mounted piezoelectric vibrator 40 by molding the piezoelectric vibrator 20 containing the piezoelectric vibrating piece 25 with a mold resin 41, and therefore other surface-mounted parts such as semiconductor parts. In the same manner as above, parts are mechanically mounted by an automatic mounting machine. Then, the electrode terminal 42a on the airtight terminal side and the electrode terminal 42b on the sealing tube side are placed on a land (not shown) on a predetermined mounting substrate to be mounted and fixed by soldering. As a result, the drive voltage from the outer lead 23b, the inner lead 23a, the sealing tube 21, the metal ring 24, and the metal wire 33 to the piezoelectric vibrating piece 25 via the substrate and the electrode terminals 42aa and 42ba in the mounting device. Is applied to vibrate at a predetermined vibration frequency. Then, this vibration can be extracted electrically and used for a predetermined clock signal of a device to be incorporated.

The perspective view which shows the whole external appearance of the piezoelectric vibrator of this embodiment. The perspective view which shows the internal structure of the piezoelectric vibrator of this embodiment. (A) The perspective view of the airtight terminal of this embodiment, (b) The cross-sectional perspective view of the airtight terminal of this embodiment. The perspective view which shows the electrode structure of the piezoelectric vibrating piece of this embodiment. FIG. 3 is a front sectional view of the piezoelectric vibrator of the present embodiment. FIG. 3 is a side cross-sectional view of the piezoelectric vibrator of the present embodiment. (A) The whole perspective view of the surface mount type piezoelectric vibrator of this embodiment, (b) The perspective view which shows the internal structure of the surface mount type piezoelectric vibrator of this embodiment. FIG. 8 is an exploded perspective view of the configuration of FIG. 7. (A) A cylinder type package piezoelectric vibrator. (B) An electrode terminal on the airtight terminal side. (C) An electrode terminal on the sealed tube side. (D) Mold resin. The electrode terminal expansion perspective view of the airtight terminal side of FIG. FIG. 9 is an enlarged perspective view of an electrode terminal on the sealing tube side of FIG. 8. The schematic perspective view for demonstrating the conventional piezoelectric vibrator. FIG. 6 is an external perspective view for explaining a conventional surface mount piezoelectric vibrator. FIG. 6 is a schematic cross-sectional view showing an internal structure for explaining a conventional surface mount piezoelectric vibrator. (A) AA sectional drawing of FIG. 13, (b) AA sectional drawing at the time of miniaturizing (a).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Airtight terminal 2 Inner lead 3 Outer lead 4 Piezoelectric vibration piece 5 Sealing pipe 6 Piezoelectric vibrator 7 Metal ring 10 Surface mount type piezoelectric vibrator 11 Electrode terminal 12 Depression part 20 Piezoelectric vibrator 21 Sealing pipe 22 Airtight terminal 23 Lead Terminal 23a Inner lead 23b Outer lead 24 Metal ring 25 Piezoelectric vibrating piece 26 Opening portion 27 Sealing glass 28 Small diameter portion 29 Space 30 Flat step surface 31 Excitation electrode 32 Mount electrode 32a First mount electrode 32b Second mount electrode 33 Metal Wire 34 Stepped portion 40 Surface mount type piezoelectric vibrator 41 Mold resin 42 Electrode terminal 42a Airtight terminal side electrode terminal 42aa Airtight terminal side electrode terminal horizontal portion 42ab Airtight terminal side electrode terminal vertical portion 42b Sealing tube side Electrode terminal 42ba Horizontal portion 42bb of the electrode terminal on the sealing tube side Hanging of the electrode terminal on the sealing tube side Junction of the junction 44b sealing tube side parts 43 notches 44a hermetic terminal side

Claims (17)

An airtight terminal in which one lead terminal penetrating through an insulating material filled in a metal ring is sealed;
A piezoelectric vibrating piece supported by an inner lead of the lead terminal and having two excitation electrodes and two mount electrodes formed on the surface;
A metal bottomed cylindrical sealing tube that houses the piezoelectric vibrating piece and whose opening is hermetically sealed with the metal ring of the hermetic terminal;
A piezoelectric vibrator having
The lead terminal has a circular cross-sectional shape and is arranged at the center position of the metal ring,
The inner lead has a flat step surface parallel to the axial center line of the metal ring and spaced a predetermined distance from the center line,
The piezoelectric vibrator is supported by the flat step surface so as to be parallel to a substantially central position of the sealing tube.   2. The piezoelectric vibrator according to claim 1, wherein one of the two mount electrodes of the piezoelectric vibrating piece is formed on each of the front and back surfaces of the mount portion supported by the inner lead. The metal ring has a small diameter portion parallel to the center line of the metal ring on the inner lead side,
The first mount electrode of the two mount electrodes is connected to the flat step surface of the inner lead,
The piezoelectric vibrator according to claim 1, wherein the second mount electrode is connected to the small diameter portion.   4. The piezoelectric vibrator according to claim 1, wherein the second mount electrode and the small diameter portion are connected by a metal wire. 5.   The flat stepped surface exceeds the position of the center line of the metal ring and is equal to or less than the distance of the thickness of the piezoelectric vibrating piece from the center line of the metal ring. The piezoelectric vibrator according to claim 1.   6. The piezoelectric vibrator according to claim 1, wherein a diameter of the lead terminal is 25% or more and 40% or less of an innermost diameter of the metal ring. .   7. The piezoelectric vibrator according to claim 1, wherein a thickness of the flat stepped surface is 60% or more and 70% or less of a diameter of the lead terminal. .   8. The piezoelectric vibrator according to claim 1, wherein a length of the small diameter portion is 0.05 mm or more and 0.15 mm or less.   The piezoelectric vibrator according to claim 1, wherein an outer diameter of the sealing tube is 0.8 mm or less. The piezoelectric vibrator according to any one of claims 1 to 9,
An electrode terminal for establishing electrical continuity between the piezoelectric vibrator and the outside;
A mold resin covering the piezoelectric vibrator;
A surface-mounted piezoelectric vibrator characterized by comprising:   The electrode terminal is formed by a horizontal portion disposed at both ends in the longitudinal direction of the piezoelectric vibrator and electrically connected to the outside, and a vertical portion where a part of the electrode terminal is bent. The surface-mount piezoelectric vibrator according to claim 10.   The vertical portion of the electrode terminal on the airtight terminal side is orthogonal to the longitudinal direction of the surface-mount piezoelectric vibrator, and the vertical portion of the electrode terminal on the sealing tube side is the longitudinal length of the surface-mount piezoelectric vibrator. The surface-mount piezoelectric vibrator according to claim 10 or 11, which is parallel to the direction.   11. The electrode terminal is connected to the lead terminal at the vertical portion on the airtight terminal side and is connected to the sealing tube at the horizontal portion on the sealing tube side. Item 13. The surface-mount piezoelectric vibrator according to any one of Items 12 to 13.   The electrode terminal on the airtight terminal side bends and raises the vertical portion from the longitudinally outer central portion of the surface-mount piezoelectric vibrator, and the sealing portion is placed in the longitudinally inner central portion of the surface-mount piezoelectric vibrator. The surface-mount type piezoelectric vibrator according to any one of claims 10 to 13, wherein the pipe has a notch.   The electrode terminal on the sealing tube side is bent and raised from the outside in parallel to the longitudinal direction of the surface-mounted piezoelectric vibrator at the inner side in the longitudinal direction of the surface-mounted piezoelectric vibrator. The surface-mount type piezoelectric vibrator according to claim 10, wherein a vertical portion that can be supported is formed.   The surface-mount type piezoelectric vibrator according to claim 10, wherein the electrode terminal has a thickness of 0.1 mm or less.   17. The surface-mount type piezoelectric vibrator according to claim 10, wherein a height of the surface-mount type piezoelectric vibrator is 0.9 mm or less.

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