JPH0739222Y2 - Surface mount electronic components - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the structure of surface mount electronic components such as oscillators.

[0002]

2. Description of the Related Art The structure of a conventional surface mount type electronic component will be described with reference to FIG. 5, taking an oscillator as an example. FIG. 5 is a perspective view showing a conventional chip oscillator. With the miniaturization of electronic devices, it is required that electronic components have a low total height and be densely mounted on a printed wiring board, and that the mounting is performed by an automatic machine. In order to meet this demand, there has been an urgent movement to make electronic parts thin and leadless chip type. The chip type oscillator as shown in FIG. 5 is provided with an extraction electrode on the lower surface thereof, and the extraction electrode is connected to an external electrode such as a printed wiring board. This connection is a flow of automation of assembly of electronic devices, and electromechanical bonding of a chip oscillator to a printed wiring board is often performed by reflow soldering. The reflow soldering is a method in which an appropriate amount of solder is supplied in advance to a joint and the solder is melted by a heat source from the outside to perform soldering.

[0003]

[Problems to be Solved by the Invention] This has the following drawbacks. Ceramic packages are often used, and the price is often high. Although the package is sealed using solder or low melting point glass, the airtightness is lower than that obtained by resistance welding using a metal case. Change over time is relatively large and product reliability is low. The present invention has been made to eliminate these drawbacks.

[0004]

In order to solve the above problems, the surface mount electronic component of the present invention has a metal base having a plurality of electrically independent lead terminals. In an electronic component sealed with a metal cap, an insulating base is installed on the lower surface of a metal base, and a recess having a depth equal to the length of the outer lead of the lead terminal is provided on the upper surface of the insulating base. Penetrates the side surface of the insulating base and is exposed at the bottom surface of each recess, and is disposed on the lower surface side of the insulating base along the outer wall surface to the lower surface, thus being surface-mounted.

There is a metal base having a plurality of electrically independent lead terminals, and an insulating base is installed on the lower surface of the metal base of an electronic component sealed with a metal cap. At least two or more opposing positionings on the upper surface of the insulating base in the insulating base having a recess on the upper surface having a depth similar to the length of the outer lead of the lead terminal and having a lead terminal plate on the bottom of each recess. Had a projection for.

[0006] There is a metal base having a plurality of electrically independent lead terminals, and an insulating base is installed on the lower surface of the metal base of an electronic component sealed with a metal cap. In the insulating base having a recess having a depth similar to the length of the outer lead of the lead terminal on the upper surface and having a lead terminal plate arranged on the bottom surface of each recess, the conductive bonding material does not overflow into each recess. A groove was provided on the.

[0007]

By providing an insulating base on the lower surface of the metal base and converting the electronic parts into chip parts, it is possible to provide a reliable product having higher airtightness than the electronic parts using the conventional ceramic package.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings, taking an oscillator as an example and explaining the structure of a surface mount electronic component. 1 is a perspective view showing an embodiment of the present invention, FIG. 2 is a perspective view of an insulating base showing an embodiment of the present invention, and FIG. 3 is an exploded sectional view showing an embodiment of the present invention. FIG. 4 is a plan view of an insulating base according to an embodiment of the present invention. In addition, the same numbers are attached to the same types or similar parts as those in the drawings in other embodiments and conventional embodiments. The base 4 is made of metal. A lead terminal 6 is hermetically sealed and insulated from the base 4 via a glass 5 and has a ground terminal 61. A substrate 7 is provided on an upper surface of the lead terminal 6, and an IC 10 forming an external circuit, an electronic component 11 such as a resistor, and a support 8 made of a metal pillar or the like for supporting a piezoelectric plate 9 are mounted on the substrate surface. Connections are made. Further, although not shown, a piezoelectric plate 9 having electrodes formed thereon is mounted on the upper portion of the support, and electrically and mechanically joined by a conductive joining material. The base 4 and the cap 12 made of metal are hermetically sealed. The insulating base 1 is made of resin or the like. The upper surface of the insulating base 1 has a recess 113, a recess 114, and a recess 115 having the same depth as the length of the outer lead of the lead terminal 6, and the lead terminal plate 2 is exposed and insulated from the bottom of each recess. It penetrates the side surface of the plate 1 and is arranged on the lower surface side of the insulating base 1 along the outer wall surface to the lower surface. The recess 11 of the insulating base 1 formed as described above
3, the concave portion 114, and the concave portion 115 in the conductive bonding material 3 respectively.
And the lead terminals 6 and 6 of the oscillator formed as described above are brought into contact with the respective lead-out terminal plates 2, 2 and 2 on the bottom surface of the recess, and the insulating base 1
While the oscillator is mounted on, heat to fix and bond. In this case, the through hole 22 may be provided as shown in FIGS. 2 and 4, and the lead terminals 6 and 6 / ground terminal 61 may be elongated to penetrate the through hole 22.

An embodiment in which a positioning projection is provided on the insulating base will be described. The insulating base 1 is made of resin or the like. On the upper surface of the insulating base 1, the recess 113, the recess 114, and the recess 115 having the same depth as the length of the outer lead of the lead terminal 6 are formed.
The lead-out terminal plate 2 is exposed on the bottom surface of each recess, and penetrates the side surface of the insulating plate 1 and is arranged on the lower surface side of the insulating base 1 along the outer wall surface to the lower surface. Further, at least two or more opposing positioning projections 112a and 112b are provided on the upper surface of the insulating base 1, and the base 4 of the oscillator is provided with normal positioning corners.
12a is provided with a locking groove 23 for inserting the corner portion. By providing the protrusions 112a and 112b, when mounting the oscillator, it is possible to eliminate the deviation and improve the mounting accuracy.

An embodiment in which a groove is provided in each recess of the insulating base will be described. The insulating base 1 is made of resin or the like. The upper surface of the insulating base 1 has a recess 113, a recess 114, and a recess 115 having the same depth as the length of the outer lead of the lead terminal 6, and the lead terminal plate 2 is exposed and insulated from the bottom of each recess. It penetrates the side surface of the plate 1 and is arranged on the lower surface side of the insulating base 1 along the outer wall surface to the lower surface. Therefore,
A groove 111, which is shallower than the bottom surface of the recess, is provided in each of the recesses at the shortest distance toward the outer wall surface. There may be one groove 111 or a plurality of grooves 111 in each recess. By providing the groove 111, when the conductive bonding material is injected, it is possible to prevent the conductive bonding material 3 from overflowing and connecting to the conductive bonding material or the lead-out terminal plate in the adjacent recess to cause a short circuit accident.

Positioning projections 112a, 11 are provided on the insulating base.
An example in which a groove is provided in 2b and each recess will be described. The insulating base 1 is made of resin or the like. The upper surface of the insulating base 1 has a recess 113, a recess 114, and a recess 115 having the same depth as the length of the outer lead of the lead terminal 6, and the lead terminal plate 2 is exposed and insulated from the bottom of each recess. It penetrates the side surface of the plate 1 and is arranged on the lower surface side of the insulating base 1 along the outer wall surface to the lower surface. Therefore, in each of the recesses,
A groove 111 that is shallower than the bottom surface of the recess is provided at the shortest distance toward the outer wall surface so as not to intersect the recesses. There may be one groove 111 or a plurality of grooves 111 in each recess. Further, at least two or more opposing positioning projections 112a and 112b are provided on the upper surface of the insulating base 1. Oscillator base 4
Is normally provided with a corner for positioning, and the projection 112a
An engaging groove 23 for inserting the above-mentioned corner portion is provided in the.

[0012]

[Effects of the Invention] The effects of the present invention are as follows. Compared with the conventional electronic parts using a ceramic package, the electronic parts of the present invention are sealed by metal-to-metal bonding such as resistance welding using a metal base and a cap, so that airtightness is not impaired and changes over time There is no. Further, since it is difficult to transmit strain stress from the outside to the inside of the electronic component, it is possible to provide a highly reliable surface mount type electronic component by combining with the insulating base. By providing a positioning projection on the insulating base, when mounting an electronic component or the like, a deviation can be eliminated and the mounting accuracy can be improved. By providing a groove in each recess of the insulating base, it is possible to prevent the conductive bonding material 3 from overflowing and connecting to the adjacent recess to cause a short circuit accident when the conductive bonding material is injected. A highly reliable surface mount electronic component can be provided.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a perspective view of an insulating base according to an embodiment of the present invention.

FIG. 3 is an exploded sectional view showing an embodiment of the present invention.

FIG. 4 is a plan view of an insulating base according to an embodiment of the present invention.

FIG. 5 is a perspective view showing a conventional chip oscillator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulation stand 2 Lead-out terminal board 3 Conductive joining material 4 Base 5 Glass 6 Lead terminal 61 Earth terminal 7 Substrate 8 Support 9 Piezoelectric plate 10 IC 11 Electronic component 12 Cap 13 Chip oscillator 111 Groove 112a, 112b Protrusion 113, 114, 115 recess 22 through hole 23 locking groove

Claims (3)

[Scope of utility model registration request] 1. There is a metal base having a plurality of electrically independent lead terminals, and in an electronic component sealed with a metal cap, an insulating base is installed on the lower surface of the metal base, The upper surface of the insulating base has a recess having a depth equal to the length of the outer lead of the lead terminal, and the lead-out terminal plate penetrates the side surface of the insulating base and is exposed at the bottom of each recess and the outer wall surface of the insulating base. A surface mount type electronic component, characterized in that it is disposed on the lower surface along with and is surface mounted. 2. The surface mount type electronic component according to claim 1, wherein at least two or more opposing projections for positioning are provided on the upper surface of the insulating base. 3. The surface mount type electronic component according to claim 1 or 2, wherein each recess is provided with a groove shallower than the bottom surface of the recess toward the outer wall surface.