JP3358822B2 - Variable 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 method in which a rotor member is rotatably mounted on an upper surface of an insulating substrate, such as a variable chip resistor, and the resistance value or the like is adjusted by rotating the rotor member. The present invention relates to a variable electronic component.

[0002]

2. Description of the Related Art Generally, a variable chip resistor is provided on an upper surface of a ceramic insulating substrate having through holes opened on both upper and lower surfaces, as described in, for example, Japanese Utility Model Application Laid-Open No. 2-102703. A resistive film is coated and formed so as to surround the hole, and a metal plate bowl-shaped rotor member having a contact portion with the resistive film is rotatable by caulking a spindle inserted through the through hole. The resistance value is adjusted by rotating the rotor member and changing the position where the contact portion of the rotor member contacts the resistive film.

[0003]

However, when the rotor member is directly in contact with the upper surface of the insulating substrate as in the prior art, the coefficient of friction of the ceramic with respect to the metal is small, so that the insulating member and the rotor member are in contact with each other. In addition to the low frictional resistance between the rotor member and the rotor member, the swaged portion of the support shaft and the rotor member are worn during rotation of the rotor member, and the frictional resistance between the swaged portion of the support shaft and the rotor member is reduced. Therefore, the function of holding the rotor member by the support shaft decreases with the rotation of the rotor member. For this reason, after the resistance value is adjusted, the rotor member can easily rotate just by touching an object on the rotor member. Therefore, there is a problem that the resistance value is easily changed.

[0004] In general, the manufacturing of the insulating substrate is performed by manufacturing a ceramic material plate in which a large number of the insulating substrates are aligned vertically and horizontally and connected to each other. After applying a resistor paste by screen printing to the part and baking to form a resistive film, forming side electrodes, etc., and finally breaking the ceramic material plate for each insulating substrate However, the position of the resistive film may deviate from a predetermined position due to a shift in the printing position of the resistive paste on the ceramic material plate, etc., so that the lower surface of the rotor member is in contact with the resistive film. There is a problem that a defective product whose resistance value cannot be adjusted is likely to be generated in a contact state.

[0005] In order to solve these problems,
A spacer made of synthetic resin is fitted to the support shaft inserted into the through hole of the insulating substrate, and the rotor member is mounted on the insulating substrate via the spacer. By forming the spacer from a material with a high coefficient of friction, the rotor member can be reliably held in the posture after rotation, preventing unexpected changes in resistance and improving resistor performance. In addition, even if the position where the resistive film is formed is displaced, the insulating spacer can prevent the lower surface of the rotor member from contacting the resistive film. As a result, the occurrence of defective products can be reliably prevented.

However, in such a configuration in which the spacer made of synthetic resin is formed separately from the insulating substrate and is fitted on the support shaft, the spacer is supported during the assembly process of the electronic component. Since it is necessary to add a transfer device for continuously feeding toward the shaft and a device such as a suction collet for picking up spacers sent by the transfer device one by one and fitting the support shaft, Not only is the manufacturing equipment for electronic components extremely complicated, but also the assembly speed is reduced by the process of fitting the spacer to the support shaft, and the manufacturing efficiency is reduced.
There has been a new problem that the manufacturing cost of electronic components increases significantly.

SUMMARY OF THE INVENTION It is an object of the present invention to improve the performance of a variable electronic component and reduce the rejection rate without increasing the manufacturing cost.

[0008]

In order to achieve this object, the present invention provides a method for manufacturing a semiconductor device, comprising the steps of enclosing an adjusting film such as a resistive film on an upper surface of an insulating substrate having through holes opened on both upper and lower surfaces. A rotor member having a contact portion for the adjustment membrane is rotatably mounted on a support shaft inserted into the through hole, and is provided between the upper surface of the insulating substrate and the lower surface of the rotor member. A variable electronic component comprising a ring-shaped spacer that imparts frictional resistance to the rotation of the rotor member inserted so as to be fitted on the support shaft, wherein the spacer is made of a synthetic resin having a large friction coefficient; The thickness is made larger than the thickness of the adjusting film, and the outer diameter thereof is made substantially equal to the outer diameter of a portion of the rotor member that contacts the spacer, and is fixedly formed on the upper surface of the insulating substrate. . "

[0009]

As described above, when the synthetic resin spacer for the rotor member is fixedly formed on the upper surface of the substrate,
Since it is not necessary to separately provide a device for fitting the spacer to the support shaft in the electronic component assembling process, it is possible to reliably avoid a complicated electronic component assembling apparatus and a reduction in assembly efficiency. .

Therefore, according to the present invention, the advantage of interposing a synthetic resin spacer between the insulating substrate and the rotor member, that is, the electronic component can be reliably held in the posture after the rotor member is rotated. Variable electronic component that has the advantage that the performance of the electronic component can be improved and the advantage that the lower surface of the rotor member can be prevented from coming into contact with the adjusting film and the incidence of defective products can be significantly reduced. Can be manufactured at low cost.

[0011]

Next, an embodiment in which the present invention is applied to a chip variable resistor will be described with reference to the drawings (FIGS. 1 to 3).

In FIG. 1, reference numeral 1 denotes a chip variable resistor. The resistor 1 includes a ceramic insulating substrate 2 having a through hole 3 opened in the upper and lower surfaces at a substantially central portion, and a bowl made of a metal plate. And a rotor member 4 formed in a mold.
A resistance film 5 is formed in the shape of
By crimping a cylindrical support shaft 6 inserted from below into the through hole 3 (the caulking portion is denoted by reference numeral 6a).
The rotor member 4 is provided with a contact portion 4a for the resistance film 5 while being rotatably mounted.

At this time, a ring-shaped spacer 7 made of synthetic resin for the rotor member 4 is fixedly formed on a portion of the upper surface of the insulating substrate 2 around the through hole 3 and radially inside the resistance film 5. I do. The spacer 7 has heat resistance to such an extent that it is not affected by the heat of the solder when the resistor 1 is fixed to a printed board or the like by soldering, and
It is formed of a material having a large coefficient of friction with respect to metal (for example, a polyimide resin or a silicon resin).

In addition, the spacer 7 is provided with the structure shown in FIGS.
As shown in FIG. 3, the thickness is made larger than the thickness of the resistance film 5 and the outer diameter thereof is made substantially equal to the outer diameter of a portion of the rotor member 4 that contacts the spacer 7. ing.

On one side surface of the insulating substrate 2, side electrodes 8 are formed which are connected to both ends of the resistive film 5.
The lower end of the support shaft 6 is integrally connected to a terminal plate 9 that is exposed on the other side surface of the insulating substrate 2, and the lower surface of the insulating substrate 2 is used for positioning the terminal plate 9. Recess 2a is formed.

When the spacer 8 made of synthetic resin is fixedly formed on the upper surface of the insulating substrate 2 as described above, the rotation of the rotor member 4 causes wear between the caulked portion 6a of the support shaft 6 and the rotor member 4. However, since a state in which a large frictional resistance is generated between the spacer 7 and the rotor member 4 can be maintained, the posture of the rotor member 4 after being rotated can be reliably maintained, and the performance of the resistor 1 can be improved. In addition, even if the position of the resistive film 5 is shifted, the lower surface of the rotor member 4 can be prevented from contacting the resistive film 5 due to the presence of the insulating spacer 7. Resistive film 5
This can reliably prevent the occurrence of defective products due to conduction between the two.

Since the spacer 7 is fixedly formed on the insulating substrate 2, it is not necessary to add a step of fitting the spacer 7 to the support shaft 6 when assembling the resistor 1. Can be reliably prevented from becoming complicated and the assembly efficiency is lowered.

When the thickness of the spacer 7 is made larger than the thickness of the resistance film 5 as in the embodiment, the contact of the rotor member 4 with the resistance film 5 can be more reliably prevented.

4 to 6 show a manufacturing method suitable for manufacturing the insulating substrate 2 in the above embodiment.

That is, first, as shown in FIG. 4, a ceramic material plate A in which a large number of insulating substrates 2 are connected via vertical and horizontal lines of scoring a and b is manufactured, and then as shown in FIG. Each of the insulating substrates 2 on the upper surface of the ceramic material plate A
The resistive film 5 is formed by applying a resistor paste by screen printing and baking the resist paste at each of the locations.

Next, a paste-like synthetic resin is applied by screen printing to a portion of the upper surface of the ceramic material plate A around the through hole 3 in each of the insulating substrates 2, and this is heated or air-dried. The spacers 7 are fixedly formed on each of the insulating substrates 2 by hardening by irradiating or irradiating ultraviolet rays.

Then, as shown in FIG. 6, by breaking the ceramic material plate A along the horizontal line of sight b,
A two-row raw material plate A1 in which the insulating substrates 2 are arranged in two rows is formed, and in this state, a side surface electrode 8 is applied by applying a conductive paste to one side surface of each of the insulating substrates 2 and drying the paste. After the formation, each of the two-row blanks A1 is broken along the horizontal line of sight b and the vertical line of sight a to obtain a large number of insulating substrates 2.

As described above, when the spacer 7 is fixedly formed on the insulating substrate 2 by printing such as screen printing, the insulating substrate 2 with the spacer 7 can be manufactured efficiently.

In this case, the spacer 7 is not limited to being formed at the stage of the ceramic material plate A. After the ceramic material plate A is broken on the two-line material plate A1, a paste-like composite is formed on the two-line material plate A1. At a stage before the individual insulating substrates 2 are broken, for example, by applying a resin by screen printing or the like, a synthetic resin may be fixedly formed by appropriate means such as printing.

[Brief description of the drawings]

FIG. 1 is a plan view of a chip variable resistor according to the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view of a state where a resistor is disassembled.

FIG. 4 is a plan view showing a first stage of the manufacturing process of the insulating substrate.

FIG. 5 is a plan view showing a second stage of the manufacturing process of the insulating substrate.

FIG. 6 is a plan view showing the final stage of the manufacturing process of the insulating substrate.

FIG. 7 is a perspective view of an insulating substrate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Chip variable resistor 2 Insulating substrate 3 Through hole 4 Rotor member 4a Contact part 5 Resistance film as an example of adjustment film 6 Support shaft 7 Spacer 8 Side electrode A Ceramic material plate

 ──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-63-116402 (JP, A) JP-A-60-103803 (JP, U) JP-A-3-39802 (JP, U)

Claims (1)

(57) [Claims] An adjusting film such as a resistive film is provided on an upper surface of an insulating substrate having through holes opened on both upper and lower surfaces so as to surround the through hole, and a contact portion for the adjusting film is provided. The rotor member is rotatably mounted on a support shaft inserted into the through hole, and a ring-shaped member is provided between the upper surface of the insulating substrate and the lower surface of the rotor member to impart frictional resistance to rotation of the rotor member. In a variable electronic component having a spacer interposed so as to be fitted on the support shaft, the spacer is made of a synthetic resin having a large friction coefficient, and the thickness thereof is larger than the thickness of the adjusting film. And that
The outer diameter substantially equal to the outer diameter at the portion in contact with the spacer of the rotor member, a variable electronic component, characterized in that fixed formed on the upper surface of the insulating substrate.