JP2548748Y2 - Small electronic components - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small electronic component in which an electronic component such as a variable resistor is hermetically sealed and can be soldered by a flow solder.

[0002]

2. Description of the Related Art Conventionally, for example, in a variable resistor, in order to use a flow solder when soldering the variable resistor to a circuit board, Japanese Patent Application Laid-Open No. 61-287103, Japanese Utility Model Application Laid-Open No. 62-28404, etc. As disclosed in Japanese Patent Application Laid-Open No. H11-260, there is a variable resistor in which an opening of a case is covered with a cover sheet and sealed. The cover sheet is located above a rotating body with which a driver or the like engages to adjust the resistance value of the variable resistor later, and can be easily broken by a driver or the like at the time of adjustment.

The Japanese Utility Model Laid-Open Publication No. 62-28404 discloses a cover sheet in which positioning marks are displayed.

[0004]

In the case of the above-mentioned prior art, the cover sheet must be securely bonded to the opening of the case of the variable resistor to prevent solder from entering the case. The seat itself must also not break during operation or transport. Therefore, when breaking the cover sheet and adjusting the resistance value, a relatively large force is required to break the cover sheet, and conversely, if the cover sheet is weakened to solve this, it will break before soldering. Due to the suction device
To be mounted on the mother board
In short, there was a conflicting problem that the function did not work.

Further, the positioning mark disclosed in Japanese Utility Model Laid-Open Publication No. 62-28404 only has a coating material for the mark applied to the center, and has no function of reinforcing the cover sheet. Further, a cap integrally molded as disclosed in Japanese Utility Model Application Laid-Open No. 61-144606,
In some cases, a thin portion is provided on the radiation, but in this case, it is difficult to mold the thin portion, and it is difficult to form the thin portion to such an extent that it is easily broken.

The present invention has been made in view of the above-mentioned conventional problems, and has a relatively high strength. Further, when the movable part is moved, the cover sheet is easily broken. It is an object of the present invention to provide a small electronic component in which automatic adjustment and the like are easy.

[0007]

According to the present invention, a small electronic component having a movable portion inside has a case in which at least one surface is an opening, and the movable portion is arranged inside, and the opening is formed in the small electronic component. A small electronic component provided with a cover sheet made of a resin film or the like to be covered and hermetically sealed, and closely adhered to and reinforced with the cover sheet, and provided with a covering member having a through hole formed at a predetermined position on the cover sheet.

[0008]

The small electronic component according to the present invention covers the opening of the case with a cover sheet and seals it to prevent the inflow of solder and the like, and further covers the cover sheet with a cover member to prevent the cover sheet from being broken. This is a small electronic component in which a through hole is formed at a predetermined position of the member so that a portion of the cover sheet exposed by the through hole can be easily broken when adjusting an internal movable member or the like.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 to 3 show a first embodiment of the present invention. A variable resistor 1 has a current collecting electrode terminal 3 protruding from a bottom surface in a case 2 having an upper surface as an opening. A lead terminal 4 integrated with the collecting electrode terminal 3 is provided along the bottom surface of the case 2, and a part thereof is exposed outside the bottom surface of the case 2 and is formed flush with the surface thereof. Current collecting electrode terminal 3
Is fitted with a resistor substrate 6 having a fitting hole 5 formed in the center, and a slider 7 and a rotating body 8 are further fitted therein. The resistor substrate 6 is fixed to the bottom surface in the case 2 and a resistor 9 is formed on the upper surface thereof by printing, and the contact 7a of the slider 7 is in slidable contact.
Are soldered. The slider 7 and the rotating body 8 are integrally formed by caulking, and are rotatable with respect to the current collecting electrode terminal 3. Further, the rotating body 8 is formed with an engagement portion 8a with which an adjustment jig such as a screwdriver is engaged.

[0010] Figure 2 is the opening of the case 1, as shown in FIG. 3, the rotating body 8 is positioned at the top, opposed to the upper surface of the rotary member 8, to the opening Close contact without gap
The cover sheet 10 covering the entire opening is
Glued to the periphery of the mouth . This cover sheet 10
The opening of the case 2 is sealed to prevent solder and solvent from entering the case 2, and is made of a thin, relatively fragile material such as a synthetic resin film, a metal foil, or a laminated film thereof. Further, a covering member 11 such as a vinyl resin is provided on an outer surface of the cover sheet 10. The covering member 11 can withstand immersion in the molten solder, and is formed on the surface of the cover sheet 10 by screen printing. The covering member 11 is provided with an engaging portion 8 a of the rotating body 8.
Is formed so as to be a through hole 11a, and this through hole 11a serves as a mark of the engaging portion 8a of the rotating body 8.

To attach the variable resistor 1 of this embodiment to a circuit board (not shown), the variable resistor 1 is adhered to a predetermined position on the circuit board and soldered by a flow solder. Then, the flux is washed with the solvent, and the mounting is completed.

Next, in order to adjust the resistance value, the opening 11a of the covering member 11 is pressed by an adjusting jig such as a screwdriver to break the cover sheet 10 and to engage the engaging portion 8 of the rotating body 8.
The adjustment jig is engaged with a, and the rotating body 8 is rotated to adjust the resistance value.

According to the variable resistor 1 of this embodiment, since the opening of the case 2 is sealed by the cover sheet 10, the solder does not enter the case 2 even when soldering by the flow solder. The cover sheet 10 is covered by the covering member 11 with a slight hole 11a left, and can sufficiently withstand the heat caused by the molten solder. In addition, when adjusting the resistance value, the through-hole 11 can be easily adjusted by the adjusting jig.
The cover sheet 10 exposed at a can be broken, and the adjustment operation can be easily performed.

The mechanical strength of the through-hole 11a is limited to the central portion of the cover sheet 10 and the periphery is reinforced by the covering member 11, so that the strength can be increased. The cover sheet 10 will not be torn even for work such as attaching the cover sheet. In addition, the slide
The upper surface of the slider 7 is flat, and this part is transferred onto the motherboard.
At this time, the suction by the suction tool is easy and reliable. Ma
In addition, since the covering member 11 can be formed by printing, it can be provided inexpensively and easily.

Next, a second embodiment of the present invention will be described with reference to FIGS. Here, the same members as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. In this embodiment, a covering member 14 made of a thin synthetic resin film covering the outer surface of the cover sheet 10 and the side surface of the case 2 is used.
Is provided. This synthetic resin film is used for the variable resistor 1
What is necessary is just to reinforce the cover sheet 10 in close contact with the variable resistor 1 after covering the variable resistor 1 using a heat-shrinkable material.
It may be one that is brought into close contact by heating. In addition, the covering member 14
A circular through hole 14a is formed at a position corresponding to the engaging portion 8a of the rotating body 8 in the center of the rotating body 8.

Thus, also in this embodiment, the cover sheet 10 is reinforced by the covering member 14 made of a synthetic resin film, and a portion corresponding to the engaging portion 8a of the rotating body 8 is provided with a through hole 14a. It can be easily broken by the adjustment jig. In particular, in this embodiment, the side surface of the variable resistor 1 is covered by the covering member 14 of the synthetic resin film, so that the protection is more sufficiently performed.

The present invention can be applied to all small electronic components having movable parts, such as variable capacitors, variable-capacitance chip capacitors and switches, which are soldered to circuit boards and the like, in addition to variable resistors. is there. Also, the shape of the through-hole in the covering member can be variously modified, and it is sufficient that the through-hole is provided corresponding to the movable portion.

[0018]

According to the invention, the opening of the case of the small electronic component is covered with a cover sheet, and the cover sheet is further covered with a cover member to reinforce the cover member, and a through hole is formed at a predetermined position of the cover member. Therefore, when moving the movable portion in the case, the cover sheet exposed from the through hole is easily torn, and the adjustment of the movable portion can be easily performed.

Further, the cover sheet seals the opening of the case and is supported planarly by the upper part of the movable member.
Thus, the mechanical strength is also increased, so that no solder or various cleaning solvents enter the case. Furthermore, the cover member also improves the mechanical strength, so that the cover sheet is not broken during transportation, and the tightness of the cover sheet is impaired even when the small electronic component is mounted on a circuit board or the like by an automatic machine. Nor. In addition, whether the strength is high
The case can also be made thinner, making this electronic component smaller.
To contribute.

Further, since the through hole of the covering member serves as a mark of the position of the movable portion in the case, even when the movable portion is adjusted by an automatic machine, the through hole is easily optically detected. This greatly contributes to automation of assembly of electronic devices.

[Brief description of the drawings]

FIG. 1 is a plan view showing a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1 of the present invention.

FIG. 3 is a plan view of the variable resistor according to the embodiment of the present invention before a cover sheet is attached.

FIG. 4 is a perspective view of a covering member according to a second embodiment of the present invention.

FIG. 5 is a longitudinal sectional view of a second embodiment of the present invention.

[Explanation of symbols]

 2 Case 7 Slider (movable part) 8 Rotating body (movable part) 10 Cover sheet 11, 14 Covering member 11a, 14a Through-hole

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-59-10222 (JP, A) JP-A-61-117205 (JP, U) JP-A-61-144606 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] 1. A case having a movable part capable of mechanically moving with an electric action, accommodating the movable part therein, and having at least one surface as an opening; Cover and seal, and set almost in contact with the upper surface of the movable part.
And cover the thin cover sheet and the movable member on the cover sheet .
A covering member having a through hole serving as a mark in a corresponding predetermined range .