JP2000200702A - Chip component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the chip component which can excellently and stably be mounted on a substrate, etc. SOLUTION: This chip component is equipped with regular polygonal prism parts 2a integrally and symmetrically at both end parts of a component body 2 and metal films of specific thickness are formed as terminal electrodes 5 on the end surfaces and at all flank positions of both regular prism parts 2. Both terminal electrodes 5 can surely be in a prismatic external shape similar to the external shape of both regular prism parts 2a. Namely, the terminal electrodes 5 having a regularly quadrangular prism external shape can be arranged at both end parts of the component body 2, so one of the flanks of both terminal electrodes 5 can optionally be used as a mount surface, and consequently the stability at the time of mounting is secured to surely prevent rolling, sliding, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chip component advantageous for bulk supply.

[0002]

2. Description of the Related Art A cylindrical chip resistor 101 as shown in FIG. 31 is a chip component applicable to bulk supply, in which a large number of components are collectively housed in a hopper or the like and supplied one by one.

The chip resistor 101 includes a cylindrical component body (not shown) made of a ceramic material, a resistance film 102 formed on the peripheral surface of the component body, and a resistance film 101 at both ends of the component body. Terminal electrode 1 having a cylindrical outer shape provided
03 and a resin exterior 1 that covers the resistive film 11 between the terminal electrodes.
04. Terminal electrode 1 of resistive film 102
A helical groove 102a for adjusting the resistance value is trimmed in a portion sandwiched between the reference numerals 03.

[0004]

SUMMARY OF THE INVENTION The aforementioned chip resistor 1
In the case of No. 01, since both the outer shape of the terminal electrode 103 and the outer shape of the outer package 104 are columnar, when they are supplied in bulk and mounted on a substrate or the like, problems such as rolling and slipping are likely to occur, and mounting cannot be performed stably. There is a problem. This problem is not limited to the above-described chip resistor, but may similarly occur in other chip components having similar component outlines.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a chip component which can be mounted on a substrate or the like in a good and stable manner.

[0006]

In order to achieve the above object, a chip component according to the present invention is a component having a regular polygonal prism having a larger external shape than the small external portion at both ends of the small external portion in an integrated and symmetrical manner. The main body, the metal film formed on the entire surface of the component main body, the terminal electrode formed so as to cover the metal film portion on both regular polygonal prism portions, and the metal film portion formed on the small external shape portion The main feature is that a component circuit is constituted by a metal film portion on the small external portion.

According to the chip component of the present invention, since the terminal electrodes are formed so as to cover the metal film portions on both regular polygonal pillar portions, the terminal electrodes are similar to the outer shapes of both regular polygonal pillar portions. A polygonal columnar outer shape can be reliably ensured. In other words, since terminal electrodes having a regular polygonal columnar outer shape can be arranged at both ends of the component body, any one side surface of both terminal electrodes can be arbitrarily used as a mounting surface,
Thereby, stability at the time of mounting can be ensured, and rolling and sliding can be reliably prevented.

Further, since the component circuit is constituted by the metal film portion on the small outer portion of the metal film formed on the entire surface of the component body, the component circuit is accurately formed at a position different from the terminal electrode. can do. In addition, since the periphery of the small external portion of the component body can be effectively used as the component circuit forming area, design changes that change the specifications of the component circuit can be easily performed.

Further, since the exterior is formed so as to cover the metal film portion on the small external portion, the component circuit constituted by the metal film portion on the small external portion is surely protected by the exterior having a sufficient thickness. Even if the exterior is thickened to protect the component circuit, the exterior does not cause the center of the component to expand. In addition, it is possible to compensate for the strength of a small external portion having an external shape smaller than that of the regular polygonal prism portion by using the exterior.

The above and other objects, constitutional features, and operational effects of the present invention will become apparent from the following description and the accompanying drawings.

[0011]

1 and 2 show a first embodiment of the present invention, more specifically, an embodiment in which the present invention is applied to a chip resistor. The chip resistor 1 of the present embodiment comprises a component body. 2, a resistance film 3, an exterior 4, and a metal film to be a terminal electrode 5.

The component body 2 is made of a ceramic material such as alumina, and has a regular polygonal prism-shaped regular polygonal column 2a at both ends integrally and coaxially, and a regular polygonal column 2a between the regular polygonal column 2a. It has a columnar small outer shape part whose outer shape is smaller than that. The two regular polygonal column portions 2a have a cross-sectional shape perpendicular to the longitudinal direction and a longitudinal length that match each other, and the diameter of the inscribed circle of the cross-section is larger than the cross-sectional diameter of the small external portion of the component body 2, Moreover, the four sides are symmetrically arranged so that they are located on the same plane. As shown in FIG. 3, the boundary 2b between the small external part of the component body 2 and the two regular polygonal pillars 2a is at an acute angle (about 60 in the drawing) with the center line of the component body 2.
Degree), the surface is three-dimensionally shaped like a truncated cone.
Further, the corners and ridges of the component body 2 including the regular polygonal column portion 2a are rounded by barrel polishing described later.

The resistance film 3 is made of a resistance material such as nickel chrome, and is formed with a predetermined thickness on the entire surface of the component body 2. A spiral groove 3a is trimmed on the resistive film 3 on the small external portion of the component body 2, and a spiral portion (resistance circuit) having a predetermined width and length is formed on the small external portion of the component body 2 by the trimming process. Is formed. As can be seen from FIG. 3, the resistive film 3 at the rising position of the boundary portion 2b
Is slightly larger than the thickness t1 of the other portions.

The exterior 4 is made of a resin material such as epoxy, and is disposed in an annular recess formed between the regular polygonal column portions 2a of the component main body 2, and borders with the resistive film 3 on the small external portion of the component main body 2. Part of the resistive film 3 on 2b is covered. This exterior 4
2 is smaller than the depth of the annular concave portion as a whole, and as can be seen from FIG. 2, the thickness t4 of the exterior 4 adjacent to the boundary portion 2b is slightly larger than the thickness t3 of the other portions. Has become.

The terminal electrode 5 is made of a metal film such as nickel, and is formed with a predetermined thickness on the end surfaces of the two regular polygonal prism portions 2a and on the surface of the resistance film 3 on the four side surfaces. As can be seen from FIG. 3, the edge 5a of each terminal electrode 5 is curved inward and extends to the boundary portion 2b, and covers the rest of the resistive film 3 on the boundary portion 2b.

Here, a preferred method of manufacturing the chip resistor 1 of the present embodiment will be described with reference to FIGS.

First, as shown in FIG. 4A, a material rod Z1 having a square cross section made of an unfired ceramic material obtained by a method such as extrusion molding is prepared, and the material rod Z1 has a predetermined length corresponding to the component dimensions. The unit base material K is obtained by cutting to a size. Alternatively, as shown in FIG. 3B, a material sheet Z2 of a predetermined thickness made of the same material obtained by a method such as coating is prepared, and cut into width and length dimensions corresponding to the part dimensions. The unit base material K is obtained.

Then, as shown in FIG. 5, the longitudinal end face of the unfired unit base material K is sandwiched between rotatable supports S, and the unit base K is rotated while being rotated about its axis. The central part of the material K is scraped in the circumferential direction with the cutting blade H1,
As shown in FIG. 7, an unsintered component body 2 'having integral regular polygonal pillars 2a' at both ends is formed.

In addition to the above-described method, a method for obtaining an unsintered component main body 2 ′ is, for example, a multi-cavity mold having a cavity M corresponding to a mold M as shown in FIG. A method of preparing a pair of upper and lower molds M and molding an unfired ceramic material using both molds may be used. Alternatively, a method may be employed in which after obtaining a unit base material having a circular cross section, both ends of the unit base material are pressed and deformed using an appropriate jig to form a regular polygonal column.

Next, the unsintered component body 2 'is heated to a predetermined temperature.
For example, when the unfired ceramic material is low-purity alumina of 70 to 80%, it is fired at a temperature of about 1200 to 1400 ° C., and after firing, these are collectively barrel-polished. In this barrel polishing, the corners and ridges of the component body are rounded to remove burrs and the like, and the surface of the resistive film 3 described later is appropriately roughened to improve the adhesion. As described above, the ceramic component main body 2 integrally having the regular polygonal column portions 2a at both ends as shown in FIG. 8 is obtained.

Incidentally, when the unfired unit base material K is obtained from the material bar Z1 or the material sheet Z2 shown in FIG. 4, the same component body 2 as above can be obtained even if the order of cutting and firing is changed. Can be.

Next, as shown in FIG. 9, a resistance film 3 of nickel chromium or the like is formed on the entire surface of the component main body 2 after barrel polishing by a technique such as sputtering. Since the corners and ridges of the component body 2 are rounded by the barrel polishing described above, the thickness of the resistive film 3 at the same portion does not locally decrease.

Next, as shown in FIG. 10, the longitudinal end face of the component main body 2 after the formation of the resistive film is sandwiched between supports S similar to that shown in FIG. The resistive film 3 on the portion is cut linearly with a trimming blade H2 to form a spiral groove 3a having a predetermined pitch and length, and the resistance value is set. Of course, the above-described trimming can also be performed by partially melting and evaporating the resistive film 3 by laser beam irradiation.

Next, as shown in FIG. 11, the longitudinal end face of the component main body 2 after the resistance film trimming is held by the support S similar to that shown in FIG. 5, and while being rotated about the axis thereof,
The application roller R is brought into contact with the resistive film 3 on the small external portion, and the exterior resin F separately supplied to the peripheral surface of the roller R is applied to the same portion (see FIG. 12). The width of the application roller R is slightly shorter than the longitudinal length of the small outer portion. If a resin having a low viscosity is used as the exterior resin F, the resin F is applied in the shape shown by the solid line in FIG. The shape shown by the broken line in FIG. 2 spreads due to its own viscosity and surface tension, that is, the shape that covers the resistive film 3 on the small external portion of the component body 2 and a part of the resistive film 3 on the boundary 2b. Becomes

Next, as shown in FIG. 13, a metal film to be the terminal electrode 5 is formed on the surface of the resistive film 3 on both regular polygonal column portions 2a by electrolytic plating or electroless plating. Since a slight step is left between the exterior 4 and the resistive film 3 on both regular polygonal pillars 2a, the edge 5a of the terminal electrode 5 extends inward to cover the step and Contact.

Thereafter, if necessary, a metal film such as Sn-Pb is further formed on the surfaces of both terminal electrodes 5 by electroless plating. Thus, the chip resistor shown in FIGS. 1 and 2 is manufactured.

The chip resistor 1 of this embodiment has a regular polygonal column 2a integrally and symmetrically at both ends of the component body 2, and a metal plate having a predetermined thickness is provided on both end surfaces and all side surfaces of the regular polygonal column 2a. Since the film is formed and used as the terminal electrode 5, a polygonal columnar outer shape similar to the outer shape of the two regular polygonal column portions 2a can be reliably secured on both terminal electrodes 5. That is, since the terminal electrodes 5 having a regular square columnar outer shape can be arranged at both ends of the component body 2, any one side surface of both terminal electrodes 5 can be arbitrarily used as a mounting surface. Thereby, stability at the time of mounting can be ensured, and rolling and sliding can be reliably prevented. Further, since the component itself has no front and back, it can be handled in the same manner as other square-shaped electronic components, can sufficiently cope with bulk supply, and greatly contributes to reduction in mounting cost.

Further, since the exterior 4 covering the periphery of the resistive film 3 is disposed in the annular concave portion formed between the regular polygonal column portions 2a of the component body 2, the outer shape is larger than that of the regular polygonal column portion 2a of the component body 2. However, the strength of a small external part can be compensated for by the exterior 4. In addition, the resistance film 3 around the small external portion of the component body 2 can be reliably protected by the exterior 4 having a sufficient thickness. The center of the part does not expand due to this.

Furthermore, since the resistance circuit formed around the small external portion of the component body 2 is connected to both terminal electrodes 5 on the side surface position of the regular polygonal column portion 2a, the flat surface of the regular polygonal column portion 5 is flat. The conduction between the resistance circuit and the two terminal electrodes 5 can be satisfactorily and reliably performed using the side surface. In addition, since parts other than the two regular polygonal pillar portions 2a in the component body 2 can be effectively used as the resistance circuit forming area, design changes such as changing the specification of the resistance circuit can be easily performed.

Further, the boundary portion 2b between the small external portion of the component body 2 and the regular polygonal column portion 2a is formed by a surface which forms an acute angle with the center line of the component body 2, thereby reinforcing the boundary portion 2b. Since the strength of the component body 2 can be improved, even when the diameter of the small cylindrical external portion becomes small, cracking is prevented by avoiding pressing during mounting and stress concentration on the boundary portion during transport / transportation. Can be prevented.

Furthermore, since the corners and ridges of the component body 2 are rounded, the influence of burrs and edges on the resistive film 3 and the terminal electrode 5, for example, the thickness of these parts is locally reduced at the same position. This prevents a high-quality part from being obtained.

Further, the thickness t2 of the resistive film 3 at both ends of the small external portion of the component body 2 is made thicker than the other portions, and the thickness t4 of the outer package 4 at both ends of the small external portion of the component body 2 is changed to other portions. By increasing the thickness, the component body 2
The strength of both ends of the small external portion can be improved.

Furthermore, since the edge of the exterior 4 extends to the boundary 2b between the two regular polygonal pillars 2a and the small external portion in the component body 2, the strength compensation is achieved by the exterior covering the boundary 2b. Can be performed more accurately.

Further, since the surface height of the outer package 4 is lower than each side surface of the terminal electrode 5, the center of the component does not expand due to the outer package 4.
Solder balls which may be generated at the time of soldering are received by the recesses around the outer package, so that the soldering can be performed well.

Furthermore, since the edge 5a of both terminal electrodes 5 extends to the boundary portion 2a between the two regular polygonal column portions 2a and the small external portion in the component body 2, the both terminal electrodes 5 with respect to the resistive film 3 are formed. The adhesion strength can be improved, and the problem that the terminal electrode 5 is pulled into the substrate side by soldering at the time of mounting and peels off, and the problem that the terminal electrode 5 deteriorates after mounting can be prevented. Moreover, the edge 5a of the terminal electrode 5 is
Therefore, peeling of the edge of the exterior 4 and cracking or chipping of the edge can be prevented by the contact portion of the terminal electrode 5.

In the first embodiment, the component body 2
The boundary portion between the small external portion and the regular polygonal column portion 2a is formed in a truncated conical shape. As shown in FIG. 14, the boundary portion between the small external portion of the component body 6 and the regular polygonal column portion 6a is shown. May be constituted by a surface orthogonal to the center line of the component body 6. In this case, the central surface area (resistance circuit formation region) can be increased, and the effective area for adjusting the resistance value can be increased. The degree of freedom can be increased.

Further, in the first embodiment described above, the small external portion of the component body 2 is formed in a cylindrical shape.
As shown in FIG. 5A, the small external portion of the component body 7 may be formed in the shape of a regular quadrangular prism similar to the regular polygonal column portion 7a, and the boundary portion 7b may be formed by an orthogonal plane. As shown in b), a boundary portion 8 between the component body 8 and the regular polygonal column portion 8a
b may be formed in a truncated pyramid shape.

Further, in the first embodiment, the exterior 4
Is shown lower than the side surfaces of the two terminal electrodes 5, but the surface of the exterior 4 is made up of second and third
As in the embodiment, a flat surface substantially flush with the side surfaces of the two terminal electrodes 5 may be used. In this case, the flat surface of the exterior surface is used together with the side surfaces of the terminal electrodes for more stable mounting. It can be carried out.

FIGS. 16 and 17 show a second embodiment of the present invention, more specifically, an embodiment in which the present invention is applied to a chip resistor. The chip resistor 11 of this embodiment comprises a component body 12 and a resistive film. 13, an exterior 14 and a metal cap to be the terminal electrode 5.

The component body 12 is made of a ceramic material such as alumina and has a columnar outer shape.

The resistance film 13 is made of a resistance material such as nickel chrome, and is formed with a predetermined thickness on the entire surface of the component body 12. A spiral groove 13a is trimmed at the center of the resistance film 13, and a spiral portion (resistance circuit) having a predetermined width and length is formed by the trimming.

The terminal electrode 15 is made of a metal cap such as nickel. This metal cap has a square pillar-shaped outer shape and has one end closed, and the inscribed circle of the cross section is the component body 12.
And is fitted to both ends of the component body 12 after the formation of the resistive film via a conductive adhesive or the like, and is symmetrical so that the four side surfaces of each are located on the same plane. It is arranged in.

The exterior 14 is made of a resin material such as epoxy, is disposed in an annular recess formed between the two terminal electrodes 15 of the component body 12, and covers the resistance film 13 between the terminal electrodes 15. The thickness of the package 14 matches the depth of the annular recess, and a flat surface is formed on the surface of the package 14 so as to be substantially flush with each of the four side surfaces of both terminal electrodes 15.

Here, a preferred method of manufacturing the chip resistor 11 of the present embodiment will be described with reference to FIGS.

First, as shown in FIG. 18, a material rod Z3 having a circular cross section made of an unfired ceramic material obtained by a method such as extrusion molding is prepared, and this is cut into a predetermined length dimension corresponding to the component dimensions. By cutting, a unit base material K (unfired component body 12 ') is obtained.

The method of obtaining the unfired component body 12 ′ may be, for example, one of the component body described with reference to FIG.
A method of preparing a pair of upper and lower multi-cavity molds having a cavity corresponding to the / 2 shape and molding an unfired ceramic material using both molds may be used.

Next, the unfired component body 12 'is fired at a predetermined temperature, for example, at a temperature of about 1200 to 1400 ° C. when the unfired ceramic material is low-purity alumina of 70 to 80%. Barrel polishing in batch. In this barrel polishing, the ridgeline of the component body is rounded to remove burrs and the like, and the surface of the resistive film 13 described later is appropriately roughened so as to improve adhesion.

Next, as shown in FIG. 19, a resistance film 13 of nickel chromium or the like is formed on the entire surface of the component main body 12 after barrel polishing by a technique such as sputtering. Since the ridge line of the component body 12 is rounded by the barrel polishing described above, the thickness of the resistive film 13 at the same portion does not locally decrease.

Next, as shown in FIG. 20, the longitudinal end face of the component main body 12 after the formation of the resistive film is sandwiched by the same support as in FIG. The upper resistive film 13 is scraped off linearly with a trimming blade H2 to form a spiral groove 13a having a predetermined pitch and length, and the resistance value is set. Of course, the above-mentioned trimming can also be performed by partially melting and evaporating the resistive film 13 by laser beam irradiation.

Next, as shown in FIG. 21, metal caps serving as terminal electrodes 15 are fitted to both ends of the component main body 12 after trimming the resistive film via a conductive adhesive.

Next, the component body 12 after the metal cap is fitted
5 is pinched by a support similar to that shown in FIG. 5, and while being rotated about the axis, the coating roller is brought into contact with the resistive film 13 between the terminal electrodes 15 to be separately supplied to the peripheral surface of the roller. The exterior resin F to be applied is applied slightly thicker to the same portion (see FIG. 22A). Then, before the applied exterior resin F is dried and solidified, the surface thereof is leveled using a pressing plate P parallel to each side surface of both terminal electrodes 15, and the four side surfaces of both terminal electrodes 15 are respectively formed on the surface. (See FIG. 22 (b)).

As a method of forming a flat surface on the surface of the exterior 14, in addition to the above-mentioned method, for example, after the applied exterior resin F is dried and solidified, the surface is substantially flush with each side surface of both terminal electrodes 15. A method of flattening it, a method of flattening by applying a hot plate to the applied resin F after drying and solidifying the resin for coating, and a method of flattening it by resin molding using a mold. May be formed.

Thereafter, if necessary, a metal film such as Sn-Pb is formed on the surfaces of both terminal electrodes 15 by electroless plating. Thus, the chip resistor shown in FIGS. 16 and 17 is manufactured.

In the chip resistor 11 according to the present embodiment, a metal cap having a square prism outer shape is symmetrically fitted to both ends of the component body 12 and used as the terminal electrodes 15. One side surface can be arbitrarily used as a mounting surface, whereby the stability at the time of mounting can be ensured, and rolling and slipping can be reliably prevented. Further, since the component itself has no front and back, it can be handled in the same manner as other square-shaped electronic components, can sufficiently cope with bulk supply, and greatly contributes to reduction in mounting cost.

Further, since the exterior 14 covering the periphery of the resistive film 13 is disposed in the annular concave portion formed between the regular polygonal column-shaped terminal electrodes 15 of the component body 12, the external shape of the component body is smaller than that of the terminal electrode 15. The strength of the part can be compensated by the armor 14. In addition, the resistance film 13 between the terminal electrodes 15 can be reliably protected by the exterior 14 having a sufficient thickness. No swelling.

Further, since the ridgeline of the component body 12 is rounded, the influence of burrs and edges on the resistive film 13 and the terminal electrode 15, for example, the thickness of the resistive film 13 is locally reduced at the same position. And high quality parts can be obtained.

Further, since the edge of the outer casing 14 extends to the boundary between the terminal electrode 15 in the form of a regular polygonal prism and the component body 12 between the terminal electrodes 15, the above-described strength compensation is performed by the outer casing covering the boundary. It can be performed more accurately. .

Furthermore, since a flat surface is provided on the surface of the outer casing 14 so as to be substantially flush with the side surfaces of the two terminal electrodes 15, the flat surface is used together with the side surfaces of the two terminal electrodes 15 for more stable mounting. It can be carried out.

In the second embodiment, the component body 1
Although a cylindrical outer shape is used as 2, a component having a square prism outer shape may be used as the component body 16 as shown in FIG. 23. Further, in the case of using a square main body having a quadrangular prism shape, as shown in FIG.
7 and a side surface of the terminal electrode 15 may have a predetermined angle difference (45 degrees in the figure).

In the second embodiment described above, the exterior 14
The surface height of the outer terminal 14 is substantially equal to the side surface of the both terminal electrodes 15, but the surface of the exterior 14 is lower in height than each side surface of the both terminal electrodes 15 as in the first embodiment. It may be something.

FIGS. 25 and 26 show a third embodiment of the present invention, more specifically, an embodiment in which the present invention is applied to a chip resistor.
, A resistive film 23, an exterior 24, and a metal film serving as a terminal electrode 25.

The component body 22 is made of a ceramic material such as alumina and has a columnar outer shape.

The resistance film 23 is made of a resistance material such as nickel chrome, and is formed with a predetermined thickness on the entire surface of the component body 22. A spiral groove 23a is trimmed in a small outer portion of the resistance film 23, and a spiral portion (resistance circuit) having a predetermined width and length is formed by the trimming.

The terminal electrode 25 is made of a metal film such as nickel and the like.
Is provided on the surface. The two terminal electrodes 25 have a regular quadrangular prism-shaped outer shape larger than the outer shape of the component body 22, and are symmetrical so that their four side surfaces are located on the same plane.

The exterior 24 is made of a resin material such as epoxy, is disposed in an annular recess formed between the terminal electrodes 25 of the component body 22, and covers the resistance film 23 between the terminal electrodes 25. The thickness of the exterior 24 matches the depth of the annular recess, and a flat surface is formed on the surface of the exterior 24 that is substantially flush with each of the four side surfaces of both terminal electrodes 25.

Here, a preferred method of manufacturing the chip resistor 21 of the present embodiment will be described with reference to FIGS.

First, similarly to FIG. 18, a material rod having a circular cross section made of an unfired ceramic material obtained by a method such as extrusion molding is prepared, and this is cut into a predetermined length dimension corresponding to the part dimensions. To obtain a unit base material (unfired component body).

In order to obtain an unsintered component body, in addition to the above method, for example, a pair of upper and lower multi-cavity molds having a cavity corresponding to a half shape of the component body as described in FIG. 6 are prepared. Alternatively, a method of forming an unfired ceramic material using both molds may be used.

Next, the unfired component body is fired at a predetermined temperature, for example, about 1200 to 1400 ° C. when the unfired ceramic material is low-purity alumina of 70 to 80%,
After firing, these are collectively barrel-polished. In this barrel polishing, the ridge line of the component body is rounded to remove burrs and the like, and the surface of the resistive film described later is appropriately roughened so as to improve the adhesion of the resistive film.

Next, similarly to FIG. 20, a resistance film such as nickel chrome is formed on the entire surface of the component main body after barrel polishing by a technique such as sputtering. Since the ridgeline of the component body is rounded by the barrel polishing described above, the thickness of the resistive film at the same portion does not locally decrease.

Next, similarly to FIG. 20, the longitudinal end face of the component body after the formation of the resistive film is sandwiched by the same support as in FIG. The resistive film is scraped linearly with a trimming blade to form a spiral groove having a predetermined pitch and length to set a resistance value. Of course,
The above trimming can also be performed by partially melting and evaporating the resistive film by laser light irradiation.

Next, as shown in FIG. 27, a conductive paste containing nickel powder is adhered to both ends of the component body 22 after the resistance film trimming, to form a terminal electrode 25 having a regular square columnar outer shape. As a method of forming the terminal electrode 25, as shown in FIGS. 28A and 28B, a dip table T having a square-tape-shaped recess Ta is prepared, and a conductive paste is provided in the recess Ta. A method may be employed in which after filling the DP, the component main body 22 after the resistance film trimming is pushed into the DP, the component main body 22 is pulled up after the conductive paste DP is solidified.

Next, similarly to FIG. 12, the longitudinal end face of the component main body 22 after the formation of the metal film is sandwiched by the same support as in FIG. 5, and the terminal electrode 25 is rotated while rotating about the axis. An application roller is brought into contact with the resistive film 13 between the rollers, and an exterior resin separately supplied to the peripheral surface of the roller is applied slightly thicker to the same portion. Then, before the applied exterior resin is dried and solidified, its surface is leveled using a pressing plate parallel to each side surface of both terminal electrodes 25, and the surface is substantially flush with each side surface of both terminal electrodes 25. A uniform flat surface is formed.

The method of forming a flat surface on the surface of the exterior 24 is, in addition to the above-mentioned method, for example, such that after the applied exterior resin is dried and solidified, the surface is substantially flush with each side surface of both terminal electrodes 25. A method of flattening the surface of the component body, a method of flattening by applying a hot plate to the applied resin after drying and solidifying the resin for the exterior, or forming the exterior around the component body by resin molding using a mold It may be a method of doing.

Thereafter, if necessary, a metal film such as Sn-Pb is formed on the surfaces of both terminal electrodes 25 by electroless plating. Thus, the chip resistor shown in FIGS. 25 and 26 is manufactured.

In the chip resistor 21 of the present embodiment, the terminal electrodes 25 having a regular square columnar outer shape are formed symmetrically at both ends of the component main body 22, so that either one side surface of both terminal electrodes 5 is mounted. It can be used arbitrarily as a surface,
Thereby, stability at the time of mounting can be ensured, and rolling and sliding can be reliably prevented. Further, since the component itself has no front and back, it can be handled in the same manner as other square-shaped electronic components, can sufficiently cope with bulk supply, and greatly contributes to reduction in mounting cost.

Further, the component main body 2 is attached to both ends of the component main body 22.
Since the metal film is provided so as to have a regular polygonal columnar shape larger than 2 and is used as the terminal electrode 25, the component body 2
The terminal electrode 25 having a regular polygonal columnar outer shape can be easily formed irrespective of the outer shape 2 or without changing the shape of the component body 22.

Further, since the exterior 24 covering the periphery of the resistive film 23 is disposed in the annular concave portion formed between the regular polygonal column-shaped terminal electrodes 25 of the component main body 22, the external shape of the component main body is smaller than that of the terminal electrode 25. The strength of the part can be compensated for by the armor 24. Moreover, the resistance film 23 between the terminal electrodes 25 can be reliably protected by the exterior 24 having a sufficient thickness.
Even if the thickness is increased, the center of the component does not expand due to the exterior 24.

Further, since the ridgeline of the component body 22 is rounded, the influence of burrs and edges on the resistance film 23 and the terminal electrode 25, for example, the thickness of the resistance film 23 is locally reduced at the same position. And high quality parts can be obtained.

Further, since the edge of the exterior 24 extends to the boundary between the terminal electrode 25 in the shape of a regular polygonal prism and the component body 22 between the terminal electrodes 25, the above-described strength compensation is performed by the exterior covering the boundary. It can be performed more accurately. .

Furthermore, since a flat surface substantially flush with each side surface of both terminal electrodes 25 is provided on the surface of the exterior 24, the flat surface is used together with the side surfaces of both terminal electrodes 25 for more stable mounting. It can be carried out.

In the third embodiment, the component body 2
Although a cylindrical outer shape is used as 2, as shown in FIG. 29, a component having a square quadrangular outer shape may be used as the component body 26 and the resistance film 27 may be formed on the surface of the component main body 26.
In the case where the component main body has a regular quadrangular prism shape, a side surface of the component main body and a side surface of the metal film may have a predetermined angle difference as in FIG.

In the third embodiment, the exterior 24
Is shown, the surface height of which is substantially equal to each side surface of both terminal electrodes 25. However, the surface of the exterior 24 is lower in height than each side surface of the terminal electrode 25 as in the first embodiment. It may be something.

FIG. 30 shows an example of a shape useful for mounting by soldering. FIG. 3A shows the second and third positions.
According to the embodiment, recesses 33 that are continuous in the circumferential direction are formed at both ends in the longitudinal direction of the exterior 32 adjacent to the edge of the terminal electrode 31. FIG. 3B corresponds to the first embodiment, and a recess 43 that is continuous in the circumferential direction is formed at both ends in the longitudinal direction of the exterior 42 adjacent to the edge of the terminal electrode 41. These recesses 33 and 43 are
This is useful for forming flat surfaces almost flush with the side surfaces of both terminal electrodes on the terminals 2 and 33. By receiving solder balls that may be generated at the time of soldering, they serve to prevent scattering. , Soldering can be performed well.

As described above, in each of the above embodiments, the present invention is applied to a chip resistor. However, the present invention is not limited to a chip resistor, and a component circuit is formed around a component body sandwiched between terminal electrodes. Possible electronic components, for example, a chip capacitor in which a plurality of internal electrode layers are formed around a component body via an insulating layer, a chip inductor in which a multilayer or single-layered coil conductor is formed around the component body, a component, The present invention can be widely applied to a chip jumper having a short-circuit conductor formed around a main body.

[0086]

As described in detail above, according to the present invention,
Since any one side surface of both terminal electrodes can be arbitrarily used as a mounting surface, excellent stability during mounting can be ensured, and rolling and rolling can be reliably prevented. In addition, since the parts themselves have no front and back sides, they can sufficiently cope with bulk supply, and can greatly contribute to reduction in mounting cost.

[Brief description of the drawings]

FIG. 1 is a perspective view of a chip resistor according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1;

FIG. 3 is an enlarged view of a main part of FIG. 2;

FIG. 4 is a diagram showing a unit base material forming step.

FIG. 5 is a view showing a cutting process of a unit base material.

FIG. 6 is a diagram showing another method for creating a component body.

FIG. 7 is a perspective view of an unsintered component body.

FIG. 8 is a perspective view of the component main body after barrel polishing.

FIG. 9 is a view showing a resistive film forming step.

FIG. 10 shows a trimming step.

FIG. 11 is a view showing an exterior forming step.

FIG. 12 is a diagram showing an attached state of an exterior resin.

FIG. 13 is a view showing a metal film forming step.

FIG. 14 is a perspective view showing another example of the shape of the component body.

FIG. 15 is a perspective view showing another example of the shape of the component body.

FIG. 16 is a perspective view of a chip resistor according to a second embodiment of the present invention.

FIG. 17 is a sectional view taken along line BB of FIG. 16;

FIG. 18 is a view showing a unit base material forming step.

FIG. 19 is a view showing a resistive film forming step.

FIG. 20 is a diagram showing a trimming step.

FIG. 21 is a view showing a metal cap fitting step.

FIG. 22 is a view showing an exterior forming step.

FIG. 23 is a perspective view showing another example of the shape of the component body.

FIG. 24 is a perspective view showing another fitting direction of the component body and the metal cap.

FIG. 25 is a perspective view of a chip resistor according to a third embodiment of the present invention.

26 is a sectional view taken along line CC of FIG. 25.

FIG. 27 is a perspective view showing a state in which a metal film is formed.

FIG. 28 is a view showing a metal film forming step.

FIG. 29 is a perspective view showing another example of the shape of the component body.

FIG. 30 is a cross-sectional view showing an example in which recesses are formed at both ends of the exterior.

FIG. 31 is an external perspective view of a columnar chip resistor showing a conventional example.

[Explanation of Signs] 1 ... chip resistor, 2 ... component body, 2a ... regular polygonal prism part,
2b: Boundary portion, 3: Resistive film, 4: Exterior, 5: Terminal electrode (metal film), 5a: Edge of metal film, Z1: Material rod, Z2
... Material sheet, K ... Unit base material, M ... Mold, F ... Exterior resin, 6,7,8 ... Part body, 6a, 7a, 8a ... Regular polygonal column, 6b, 7b, 8b ... Boundary part, 11: chip resistor, 12: component body, 13: resistive film, 14: exterior, 15
... Terminal electrode (metal cap), Z3 ... Material rod, 16,1
7: component body, 21: chip resistor, 22: component body,
23 ... resistive film, 24 ... exterior, 25 ... terminal electrode (metal film), 26 ... part body, 27 ... resistive film, 31 ... metal cap or metal film, 32 ... exterior, 33 ... dent, 41 ... metal film, 42 ... exterior, 43 ... dent.

Claims (1)

[Claims] A component body having integral and symmetrical regular polygonal prism portions having a larger outer shape than the small external portion at both ends of the small external portion; a metal film formed on the entire surface of the component body; A terminal electrode formed so as to cover the metal film portion on the prismatic portion, and an exterior formed so as to cover the metal film portion on the small external portion, the component circuit is formed by the metal film portion on the small external portion. A chip component comprising: