JPH0531342U - Surface mount electronic components - Google Patents

Abstract

(57) [Abstract] [Purpose] By providing an insulating base on the lower surface of the metal base and converting electronic parts into chip parts, we provide highly reliable products with higher airtightness than electronic parts using conventional ceramic packages. can do. In an electronic component having a metal cap 9 and a base 4, an insulating base 1 is installed on the lower surface of the metal base 4, and a depth equal to the length of the outer lead of the lead terminal is provided on the upper surface of the insulating base 1. Drawout terminal board 2 with through holes
Is pierced through the side surface of the insulating base 1 and is exposed at the bottom surface of each through hole, and is disposed on the lower surface along the outer wall surface of the insulating base 1 for surface mounting. Further, it is characterized in that the insertion port of the through hole is provided with a taper.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to the structure of surface mount electronic components such as piezoelectric vibrators.

[0002]

[Prior Art]

 The structure of a conventional surface mount electronic component will be described with reference to FIG. 4, taking a piezoelectric vibrator as an example. FIG. 4 is a perspective view showing a conventional chip type piezoelectric vibrator. With the miniaturization of electronic equipment, it is required that electronic components have a low total height and be mounted on a printed wiring board at a high density, and that the mounting is performed by an automatic machine. In order to meet this demand, there has been an urgent move to make electronic parts thinner and leadless chip type. A chip-type piezoelectric vibrator as shown in FIG. 4 is provided with an extraction electrode on the lower surface thereof, and the extraction electrode is connected to an external electrode such as a support of a piezoelectric plate. This connection is a trend of automation of electronic device assembly, and electro-mechanical bonding of the chip type piezoelectric vibrator to the printed wiring board is often performed by reflow soldering. Reflow soldering is a method in which an appropriate amount of solder is supplied to the joint in advance and the solder is melted by a heat source from the outside to perform soldering.

[0003]

[Problems to be solved by the device]

 This had 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, its 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]

[Means for Solving the Problems]

 In order to solve the above problems, the surface mount type electronic component of the present invention has a metal base having a plurality of electrically independent lead terminals and is sealed with a metal cap. In this electronic component, an insulating base is installed on the lower surface of the metal base, and the upper surface of the insulating base has a through hole with a depth equivalent to the length of the outer lead of the lead terminal. It penetrates and is exposed at the bottom of each through hole, and is arranged on the lower surface along the outer wall surface of the insulating base to be 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. There is a through hole on the upper surface with a depth equivalent to the length of the outer lead of the lead terminal, the lead-out terminal plate penetrates the side surface of the insulating base and is exposed at the bottom of each through hole, and on the outer wall of the insulating base A taper is provided at the insertion port of the through hole in the insulating base arranged along the lower surface.

[0006]

[Action]

 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 with higher airtightness than conventional electronic parts using a ceramic package.

[0007]

【Example】

 Next, the present invention will be described with reference to the drawings by taking a piezoelectric vibrator as an example and explaining the structure of a surface mount electronic component. 1 is an exploded sectional view showing an embodiment of the present invention, FIG. 2 is a plan view of an insulating base showing an embodiment of the present invention, and FIG. 3 is a bottom view of an insulating base showing an embodiment of the present invention. is there. The same numbers are given to the same types or similar parts as those in the drawings in other examples and the conventional examples. The base 4 is made of metal. A lead terminal 6 is hermetically and insulatively sealed to the base 4 via a glass 5. A support 7 is provided on the upper surface of the lead terminal 6, and a piezoelectric plate 8 on which electrodes are formed (not shown) is mounted on the upper portion of the support, and electrically and mechanically bonded by a conductive bonding material. There is. The base 4 and the cap 9 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 through hole 3 having the same depth as the length of the outer lead of the lead terminal 6, and the lead terminal plate 2 penetrates the side surface of the insulating base 1 and is exposed at the bottom surface of each through hole. In addition, it is arranged on the lower surface along the outer wall surface of the insulating base 1. A conductive bonding material is injected into the through holes 3 and 3 of the insulating base 1 formed as described above, and the lead terminals 6 and 6 of the piezoelectric vibrator formed as described above are attached to the bottom surface of the through hole. Each of the lead-out terminal plates 2 and 2 in FIG.

An embodiment in which the through hole insertion opening of the insulating base is tapered will be described. The insulating base 1 is made of resin or the like. The upper surface of the insulating base 1 has a through hole 3 having the same depth as the length of the outer lead of the lead terminal 6, and the lead terminal plate 2 penetrates the side surface of the insulating base 1 and is exposed at the bottom surface of each through hole. In addition, it is arranged on the lower surface along the outer wall surface of the insulating base 1. Each of the through holes was gradually recessed from the insertion port toward the bottom surface where the lead-out terminal plate 2 is provided, and was provided with a conical taper having a diameter larger than that of the through hole 3. The taper is usually provided from the insertion hole of the through-hole 3 to the middle part of the bottom surface part where the lead-out terminal plate 2 is arranged, but it should extend to the bottom part part where the drawer terminal plate 2 is arranged. Alternatively, the through hole may have a tapered shape.

[0009]

[Effect of the device]

 The effects of the present invention are as follows. Compared to conventional electronic components using a ceramic package, the electronic components 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. In addition, 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 electronic component by combining it with an insulating base. By providing the insertion hole of the through hole on the upper surface of the insulating base with a taper, the lead terminal can be easily inserted into the through hole when mounting an electronic component or the like.

[Brief description of drawings]

FIG. 1 is an exploded sectional view showing an embodiment of the present invention.

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

FIG. 3 is a bottom view of an insulating base according to an embodiment of the present invention.

FIG. 4 is a perspective view showing a conventional chip-type piezoelectric vibrator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulation stand 2 Lead-out terminal board 3 Through hole 4 Base 5 Glass 6 Lead terminal 7 Support 8 Piezoelectric plate 9 Cap 10 Conductive bonding material

Claims (2)

[Scope of utility model registration request] 1. A metal base having a plurality of electrically independent lead terminals is provided, and in an electronic component sealed with a metal cap, an insulating base is installed on the lower surface of the metal base, A through hole having a depth equivalent to the length of the outer lead of the lead terminal is formed on the upper surface of the insulating base, the lead-out terminal plate penetrates the side surface of the insulating base and is exposed at the bottom of each through hole, and A surface-mounted electronic component, which is disposed on the lower surface along the outer wall surface and is surface-mounted. 2. The surface mount electronic component according to claim 1, wherein the insertion port of the through hole is tapered on the upper surface of the insulating base.