JP4941594B2 - Ceramic electronic components - Google Patents

Description

  The present invention relates to a ceramic electronic component such as a ceramic capacitor or a ceramic varistor.

  At present, the medium- and high-voltage ceramic capacitors with a rating of 3 kV or more are mainly in the mounting type with lead wires. However, with the recent thinning of power supply substrates, the demand for surface mount types is increasing. For example, there is a surface mounting type ceramic capacitor described in Patent Document 1. This surface-mount type ceramic capacitor has ceramic elements with electrodes formed on both opposing main surfaces, two metal terminals connected to each electrode, and insulation that embeds part of the ceramic elements and metal terminals. And an exterior packaging material. The metal terminal is drawn out from the side surface of the insulating exterior material, and is bent from the side surface to the bottom end.

JP-A-5-109581

  However, in the conventional surface mount type ceramic capacitor, the metal terminal is firmly fixed by the insulating exterior material, and mechanical stress when the mounting substrate is bent is directly applied to the ceramic element, and the ceramic element is cracked. There was a problem that it occurred. Further, in the conventional surface mount type ceramic capacitor, there is a possibility that the creeping discharge when the high voltage is applied cannot be sufficiently prevented because the creeping distance of the insulating exterior material between the two metal terminals is short.

  SUMMARY OF THE INVENTION Therefore, a main object of the present invention is to provide a ceramic electronic component in which mechanical stress when a mounting substrate is bent is not directly applied to a ceramic element and creeping discharge can be prevented.

  In general, the insulating exterior material is molded by injection molding or transfer molding. However, in this case, there is a problem in the adhesion between the insulating sheathing material and the ceramic element, and considering the case where a gap is generated between the insulating sheathing material and the ceramic element, the ceramic is prevented to prevent creeping discharge. An electrode cannot be formed on the entire main surface of the element, and it is necessary to form the electrode by retreating from the outer peripheral edge of the main surface. For this reason, there is a restriction that the ceramic element cannot be reduced in size. In general, the insulating exterior material is formed by transfer molding a thermosetting resin, but the yield of the insulating exterior material is poor and the productivity is not good.

The present invention includes a ceramic substrate having a first main surface and a second main surface opposite to each other on an outer peripheral surface, a first electrode provided on the first main surface, and a second electrode provided on the second main surface, , A first metal terminal joined to the first electrode, a second metal terminal joined to the second electrode, a ceramic element, a part of the first metal terminal and one of the second metal terminals A ceramic electronic component comprising an insulating exterior material covering a portion,
The first metal terminal extends parallel to the first main surface and is joined to the first electrode, and extends parallel to the first joint and is mounted on the mounting substrate. A first mounting part, and a first relay part that connects the first joint part and the first mounting part,
The second metal terminal extends parallel to the second main surface and joined to the second electrode, and extends parallel to the second joint and is mounted on the mounting substrate. A second mounting part, and a second relay part that connects the second joint part and the second mounting part,
The insulating exterior material is provided so as to cover the ceramic element, the first joint portion, the first relay portion, and the second joint portion, and so that the first mounting portion and the second mounting portion are exposed,
In a portion where the outer peripheral surface of the ceramic substrate and the first relay portion of the first metal terminal face each other, an insulating exterior material that covers the outer peripheral surface of the ceramic substrate and an insulating property that covers the first relay portion of the first metal terminal A ceramic electronic component characterized in that a space is formed between the outer packaging material and the outer packaging material. The first electrode and the second electrode may be provided on the entire surfaces of the first main surface and the second main surface, respectively.

  In this invention, a space is formed between the insulating exterior material that covers the outer peripheral surface of the ceramic element and the insulating exterior material that covers the first relay portion of the first metal terminal. Therefore, the boundary portion between the first joint portion and the first relay portion of the first metal terminal has a spring property due to this space, and mechanical stress when the mounting board is bent is applied to the boundary portion. Mechanical stress is not directly applied to the ceramic element. Furthermore, this space increases the creeping distance of the insulating exterior material between the first mounting part of the first metal terminal and the second mounting part of the second metal terminal, and creeping discharge when a high voltage is applied. Less likely to occur. Furthermore, the amount of the insulating exterior material used is reduced, and it is not always necessary to use a mold when forming the insulating exterior material.

  Further, according to the present invention, the width dimension of the first joint portion of the first metal terminal is larger than the width dimension of the ceramic element, and the edge portion of the ceramic element recedes from the edge portion of the first joint portion in a plan view. Features. Thereby, the electric field concentration at the edge of the ceramic element is alleviated.

  According to the present invention, a fillet made of a bonding material for bonding the first electrode of the ceramic element and the first metal terminal is formed between the edge of the ceramic element and the first bonding portion, and the first A bonding material or a bonding material and an insulating exterior material are filled between the electrode and the first bonding portion. As a result, the bonding material is filled between the edge of the ceramic element and the first metal terminal, and there is no space between the first electrode and the first bonding portion, and high frequency is generated in the ceramic electronic component. Creeping discharge when applied is prevented.

  The present invention is also characterized in that the minimum distance between the second electrode and the second metal terminal of the ceramic element and the first metal terminal is equal to or greater than the thickness dimension of the ceramic substrate. Thereby, a ceramic electronic component having a design withstand voltage of the ceramic element itself can be obtained without being affected by the thickness of the insulating exterior material.

  Furthermore, the present invention is characterized in that each of the first joint portion and the second joint portion has a convex portion protruding toward the ceramic element side. As a result, a gap is formed between the first and second joint portions and the first and second main surfaces of the ceramic element, and the bending stress of the first and second metal terminals is not directly applied to the edge portion of the ceramic element.

  Furthermore, the insulating exterior material is made of an epoxy-based powder resin. By performing powder resin coating using such a material, the adhesion between the insulating exterior material and the ceramic element is improved, the yield of the insulating exterior material is improved, and the productivity is increased.

  Further, a flat portion having a diameter of about 2.5 mm or more is provided on the upper surface of the insulating exterior material, and a portion protruding upward is provided in a range having a diameter of about 4 mm or more in the same center as the flat portion. It is characterized by not. Thereby, the ceramic electronic component which can be attracted | sucked by an automatic mounting machine is obtained.

  According to this invention, since the space is formed between the insulating exterior material that covers the outer peripheral surface of the ceramic element and the insulating exterior material that covers the first relay portion of the first metal terminal, Depending on the space, the boundary portion between the first joint portion of the first metal terminal and the first relay portion has a spring property, and mechanical stress when the mounting substrate is bent is applied to the boundary portion, and mechanically. Stress is not directly applied to the ceramic element. Furthermore, this space increases the creeping distance of the insulating exterior material between the first mounting portion of the first metal terminal and the second mounting portion of the second metal terminal, and causes creeping discharge when a high voltage is applied. Can be suppressed. Further, the amount of the insulating exterior material used can be reduced, and when the insulating exterior material is formed, it is not always necessary to use a mold, so that the production efficiency is good. As a result, it is possible to obtain a ceramic electronic component in which mechanical stress when the mounting substrate is bent is not directly applied to the ceramic element, and creeping discharge can be prevented.

  The above-mentioned object, other objects, features and advantages of the present invention will become more apparent from the following description of embodiments for carrying out the invention with reference to the drawings.

(A) is a top view of the ceramic electronic component of 1st Embodiment, (B) is II sectional drawing of (A). It is a perspective view which shows a ceramic element. (A) is a top view of the ceramic electronic component of 2nd Embodiment, (B) is III-III sectional drawing of (A). (A) is a top view of the ceramic electronic component of 3rd Embodiment, (B) is IV-IV sectional drawing of (A). (A) is a top view of the ceramic electronic component of 4th Embodiment, (B) is the side view, (C) is VV sectional drawing of (A). (A) is a top view of the ceramic electronic component of 5th Embodiment, (B) is VI-VI sectional drawing of (A). (A) is a top view of the ceramic electronic component of 6th Embodiment, (B) is VII-VII sectional drawing of (A).

(First embodiment)
FIG. 1A is a plan view of the surface mount type ceramic capacitor of the first embodiment, and FIG. 1B is a cross-sectional view taken along the line II of FIG. The ceramic capacitor is formed by covering a disk-shaped ceramic element 1 made of BaTiO ₃ or the like, metal terminals 2 and 3 bonded to the front and back of the ceramic element 1, and part of the ceramic element 1 and the metal terminals 2 and 3. The insulating exterior material 4 is provided.

  The ceramic element 1 has a ceramic substrate having a front surface 11a and a back surface 11b facing each other, and an outer peripheral surface 11c. As shown in FIG. 2A, electrodes 5 and 6 are formed on the entire surface 11a and back surface 11b of the ceramic substrate 1a. The electrodes 5 and 6 are made of Ni, Cu, Ag, Cr, or an alloy mainly containing any one of these, and are formed by an electroless plating method, a vapor deposition method, or a printing method. As shown in FIG. 2B, the electrodes 5 and 6 may be formed so as to recede from the outer peripheral edge of the ceramic substrate 1a without being formed on the entire surface 11a and back surface 11b.

  The metal terminals 2 and 3 are formed by bending. That is, the metal terminal 2 extends in parallel to the surface 11a and is bonded to the electrode 5, and the mounting portion that extends in parallel to the bonding portion 20 and is mounted on the mounting substrate P. 24 and a relay part 22 that connects the joint part 20 and the mounting part 24. The joint portion 20 protrudes relatively long from the edge of the ceramic element 1, and the relay portion 22 extends in a substantially vertical direction. Similarly, the metal terminal 3 extends in parallel to the back surface 11b and is bonded to the electrode 6, and the mounting that extends in parallel to the bonding portion 30 and is mounted on the mounting substrate P. Part 34, and a relay part 32 that connects the joint part 30 and the mounting part 34. The relay part 32 extends in a substantially vertical direction. The mounting portions 24 and 34 of the metal terminals 2 and 3 are led out to the left and right opposite sides with the ceramic element 1 therebetween. The material of the metal terminals 2 and 3 is preferably a material having a linear expansion coefficient close to that of the ceramic element 1 such as SUS430. The surface of the metal terminals 2 and 3 is Sn plated, and a base plating such as Ni may be applied as necessary.

  As a bonding material between the metal terminals 2 and 3 and the electrodes 5 and 6, for example, a conductive adhesive mainly composed of Ag powder or Cu powder coated with Ag, or lead such as LF high-temperature solder is contained. Bonding material that is not used is used.

  The insulating exterior material 4 is provided so as to cover the ceramic element 1, the joint portion 20 and the relay portion 22 of the metal terminal 2, and the joint portion 30 of the metal terminal 3. The mounting portions 24 and 34 of the metal terminals 2 and 3 are exposed from the insulating exterior material 4. As the insulating exterior material 4, an epoxy powder resin, a silicone resin, or the like is used, and is formed by a dipping method or the like. In particular, when an epoxy powder resin is used as the insulating exterior material 4, it has good adhesion to the ceramic element 1 and the metal terminals 2 and 3 and can secure high sealing performance, so that creeping discharge hardly occurs. Therefore, the electrodes 5 and 6 can be formed on the entire surface 11a and back surface 11b of the ceramic substrate 1a, and a small ceramic capacitor can be obtained while maintaining high withstand voltage characteristics. In addition, by performing powder resin coating using an epoxy-based powder resin, the adhesion between the insulating exterior material 4 and the ceramic element 1 is improved, the yield of the insulating exterior material 4 is good, and high productivity is achieved. Obtainable.

  And in the part which the outer peripheral surface 11c of the ceramic substrate 1a and the relay part 22 of the metal terminal 2 oppose, the insulating exterior material 4 which coat | covers the outer peripheral surface 11c of the ceramic substrate 1a, and the relay part 22 of the metal terminal 2 are coat | covered A space S is formed between the insulating exterior material 4 to be formed.

  The surface mount type ceramic capacitor having the above configuration is formed between the insulating exterior material 4 covering the outer peripheral surface 11 c of the ceramic element 1 and the insulating exterior material 4 covering the relay portion 22 of the metal terminal 2. The creeping distance of the insulating exterior material 4 between the mounting portion 24 of the metal terminal 2 and the mounting portion 34 of the metal terminal 3 is increased by the space S, and creeping discharge when high voltage is applied is suppressed. Can do. Furthermore, due to the space S, the boundary portion between the joint portion 20 and the relay portion 22 of the metal terminal 2 has a spring property, and mechanical stress when the mounting substrate P is bent is applied to the boundary portion, Mechanical stress is not directly applied to the ceramic element 1. As a result, it is possible to obtain a ceramic capacitor in which mechanical stress when the mounting substrate P is bent is not directly applied to the ceramic element 1 and can prevent creeping discharge. Furthermore, since the usage amount of the insulating exterior material 4 can be reduced and the insulating exterior material 4 is formed, it is not necessary to use a mold, so that the production efficiency is good.

(Second Embodiment)
FIG. 3A is a plan view of the surface-mounting type ceramic capacitor of the second embodiment, and FIG. 3B is a cross-sectional view taken along the line III-III in FIG. The ceramic capacitor includes a disk-shaped ceramic element 1, metal terminals 2 and 3 bonded to the front and back of the ceramic element 1, and an insulating exterior material covering a part of the ceramic element 1 and the metal terminals 2 and 3. 4 is provided. The ceramic element 1 is the same as that described in the first embodiment, and a detailed description thereof is omitted.

  The metal terminal 2 extends in parallel to the surface 11a and is bonded to the electrode 5, and the mounting portion 24 that extends in parallel to the bonding portion 20 and is mounted on the mounting substrate P. The relay unit 22 connects the joint unit 20 and the mounting unit 24. Similarly, the metal terminal 3 extends in parallel to the back surface 11b and is bonded to the electrode 6, and the mounting that extends in parallel to the bonding portion 30 and is mounted on the mounting substrate P. Part 34, and a relay part 32 that connects the joint part 30 and the mounting part 34. The width dimensions W1 and W2 of the joint portions 20 and 30 of the metal terminals 2 and 3 are designed to be larger than the diameter D of the ceramic element 1, and the edge portion of the ceramic element 1 is the edge portion of the joint portions 20 and 30 in a plan view. It is more backward.

  The metal terminals 2 and 3 and the electrodes 5 and 6 are joined together by a joining material 7. A fillet 61 made of the bonding material 7 is formed between the edge of the ceramic element 1 and the bonding portions 20 and 30 of the metal terminals 2 and 3. The minimum distance d between the electrode 6 and the metal terminal 3 provided on the back surface 11b of the ceramic substrate 1a and the metal terminal 2 is designed to be equal to or greater than the thickness dimension T of the ceramic substrate 1a.

  The insulating exterior material 4 is provided so as to cover the ceramic element 1, the joint portion 20 and the relay portion 22 of the metal terminal 2, and the joint portion 30 of the metal terminal 3. The mounting portions 24 and 34 of the metal terminals 2 and 3 are exposed from the insulating exterior material 4.

  And in the part which the outer peripheral surface 11c of the ceramic substrate 1a and the relay part 22 of the metal terminal 2 oppose, the insulating exterior material 4 which coat | covers the outer peripheral surface 11c of the ceramic substrate 1a, and the relay part 22 of the metal terminal 2 are coat | covered A space S is formed between the insulating exterior material 4 to be formed.

  The surface mount type ceramic capacitor having the above configuration is formed between the insulating exterior material 4 covering the outer peripheral surface 11 c of the ceramic element 1 and the insulating exterior material 4 covering the relay portion 22 of the metal terminal 2. The creeping distance of the insulating exterior material 4 between the mounting portion 24 of the metal terminal 2 and the mounting portion 34 of the metal terminal 3 is increased by the space S, and creeping discharge when high voltage is applied is suppressed. Can do. Furthermore, due to the space S, the boundary portion between the joint portion 20 and the relay portion 22 of the metal terminal 2 has a spring property, and mechanical stress when the mounting substrate P is bent is applied to the boundary portion, Mechanical stress is not directly applied to the ceramic element 1. As a result, it is possible to obtain a ceramic capacitor in which mechanical stress when the mounting substrate P is bent is not directly applied to the ceramic element 1 and can prevent creeping discharge.

  In addition, the widths W1 and W2 of the joint portions 20 and 30 of the metal terminals 2 and 3 are designed to be larger than the diameter D of the ceramic element 1, and the edge of the ceramic element 1 of the joint portions 20 and 30 is seen through in plan view. Since it recedes from the edge portion, the electric field concentration at the edge portion of the ceramic element 1 can be relaxed, and a small and high withstand voltage capacitor can be manufactured. In the second embodiment, the widths W1 and W2 of the joints 20 and 30 of the metal terminals 2 and 3 are designed to be larger than the diameter D of the ceramic element 1, but at least the joints of the upper metal terminal 2 If the width dimension W1 of 20 is designed to be larger than the diameter D of the ceramic element 1, the effect of relaxing the electric field concentration at the edge of the ceramic element 1 can be obtained.

  In addition, fillets 61 made of the bonding material 7 are formed between the edge of the ceramic element 1 and the joints 20 and 30 of the metal terminals 2 and 3, respectively, and between the electrode 5 and the joint 20 and the electrode 6. And the joining portion 30 are filled with the joining material 7, respectively. As a result, the bonding material 7 is filled between the edge of the ceramic element 1 and the bonding portions 20, 30, and between the electrode 5 and the bonding portion 20 and between the electrode 6 and the bonding portion 30. Therefore, creeping discharge can be prevented when a high frequency is applied to the ceramic electronic component.

  Further, since the minimum distance d between the electrode 6 and the metal terminal 3 provided on the back surface 11b of the ceramic substrate 1a and the metal terminal 2 is designed to be equal to or greater than the thickness dimension T of the ceramic substrate 1a, the insulating property is improved. A ceramic capacitor having the design withstand voltage of the ceramic element 1 itself can be obtained without being affected by the thickness of the exterior material 4.

  Further, in the conventional ceramic capacitor, since the adhesion between the insulating exterior material and the ceramic body is difficult, the electrodes 5 and 6 are formed on the entire surface 11a and back surface 11b as shown in FIG. When the ceramic element 1 is used, there is a risk of creeping discharge when a gap is generated between the ceramic body 1 and the insulating exterior material. Therefore, in order to increase the creepage distance, conventionally, as shown in FIG. 2B, the electrode 5 is formed by retreating from the outer peripheral edge portion of the ceramic substrate 1a without being formed on the entire surface 11a and the back surface 11b. , 6 has to be provided around the gap. On the other hand, in the second embodiment, as shown in FIG. 3B, a fillet 61 is formed so that no space exists between the electrodes 5 and 6 and the metal terminals 2 and 3. Since creeping discharge is prevented, the electrodes 5 and 6 can be formed on the entire surface 11a and back surface 11b of the ceramic substrate 1a. Therefore, the portion of the ceramic substrate 1a around the electrodes 5 and 6, which has been necessary in the past, becomes unnecessary, and the ceramic element 1 can be downsized.

(Third embodiment)
FIG. 4A is a plan view of a surface mount type ceramic capacitor according to the third embodiment, and FIG. 4B is a cross-sectional view taken along the line IV-IV in FIG. The ceramic capacitor of the third embodiment is a modification of the ceramic capacitor of the second embodiment, and includes a disk-shaped ceramic element 1 and metal terminals 2 and 3 bonded to the front and back of the ceramic element 1. And an insulating exterior material 4 covering a part of the ceramic element 1 and the metal terminals 2 and 3. In FIGS. 4A and 4B, the same components and parts as those in the second embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The width dimensions W1 and W2 of the joint portions 20 and 30 of the metal terminals 2 and 3 are designed to be larger than the diameter D of the ceramic element 1, and the edge portion of the ceramic element 1 is the edge portion of the joint portions 20 and 30 in a plan view. It is more backward. At this time, the joint portions 20 and 30 of the metal terminals 2 and 3 may be designed so that the edge portion of the ceramic element 1 recedes from the edge portion of the joint portions 20 and 30. A part of the protruding joints 20 and 30 may be cut out to narrow the width dimension W1 ′. Further, as in a ceramic capacitor according to a fourth embodiment to be described later, if the joint portion 20 of the metal terminal 2 is designed so that the edge portion of the ceramic element 1 recedes from the edge portion of the joint portion 20, a hole is provided. You may provide 20a, 20b as needed.

(Fourth embodiment)
FIG. 5A is a plan view of the surface mount type ceramic capacitor of the fourth embodiment, FIG. 5B is a side view thereof, and FIG. 5C is a V- It is V sectional drawing. The ceramic capacitor includes a disk-shaped ceramic element 1, metal terminals 2 and 3 bonded to the front and back of the ceramic element 1, and an insulating exterior material covering a part of the ceramic element 1 and the metal terminals 2 and 3. 4 is provided. The ceramic element 1 is the same as that described in the first embodiment, and a detailed description thereof is omitted.

  The metal terminal 2 extends in parallel to the surface 11a and is bonded to the electrode 5, and the mounting portion 24 that extends in parallel to the bonding portion 20 and is mounted on the mounting substrate P. The relay unit 22 connects the joint unit 20 and the mounting unit 24. Similarly, the metal terminal 3 extends in parallel to the back surface 11b and is bonded to the electrode 6, and the mounting that extends in parallel to the bonding portion 30 and is mounted on the mounting substrate P. Part 34, and a relay part 32 that connects the joint part 30 and the mounting part 34. The width dimensions W1 and W2 of the joint portions 20 and 30 of the metal terminals 2 and 3 are designed to be larger than the diameter D of the ceramic element 1, and the edge portion of the ceramic element 1 is the edge portion of the joint portions 20 and 30 in a plan view. It is more backward.

  The joint portion 20 is formed with a circular hole 20a and a rectangular hole 20b extending to the relay portion 22, and a plurality of substantially conical convex portions 26 projecting toward the ceramic element 1 are provided around the circular hole 20a. Is provided. A circular hole 30a is formed in the joint portion 30, and a plurality of substantially conical convex portions 26 protruding toward the ceramic element 1 are provided around the circular hole 30a. The circular holes 20 a and 30 a are for supplying the bonding material 7 in the vicinity of the convex portion 26. A space between the electrode 5 and the bonding portion 20 and between the electrode 6 and the bonding portion 30 is filled with the bonding material 7 and the insulating exterior material 4. Thereby, there is no space between the electrode 5 and the joint part 20 and between the electrode 6 and the joint part 30, and creeping discharge when a high frequency is applied to the ceramic electronic component can be prevented. The rectangular hole 20b is for facilitating the supply of the insulating exterior material 4 to the outer peripheral surface 11c of the ceramic substrate 1a. If the thickness of the metal terminals 2 and 3 is 0.2 mm or less and the height of the convex portion 26 is about 0.2 mm or less, the step due to the circular holes 20a and 30a is filled at the stage where the insulating exterior material 4 is formed. The upper surface of the insulating exterior material 4 becomes flat and does not adversely affect the adsorption by the automatic mounting machine.

  The insulating exterior material 4 is provided so as to cover the ceramic element 1, the joint portion 20 and the relay portion 22 of the metal terminal 2, and the joint portion 30 of the metal terminal 3. The mounting portions 24 and 34 of the metal terminals 2 and 3 are exposed from the insulating exterior material 4.

  And in the part which the outer peripheral surface 11c of the ceramic substrate 1a and the relay part 22 of the metal terminal 2 oppose, the insulating exterior material 4 which coat | covers the outer peripheral surface 11c of the ceramic substrate 1a, and the relay part 22 of the metal terminal 2 are coat | covered A space S is formed between the insulating exterior material 4 to be formed.

  The surface-mounting type ceramic capacitor having the above configuration has the same effect as the ceramic capacitor of the second embodiment, and each of the joint portions 20 and 30 has a protruding portion 26 protruding to the ceramic element 1 side. Therefore, gaps are formed between the joint portions 20, 30 and the front and back surfaces 11 a, 11 b of the ceramic element 1, and the bending stress of the metal terminals 2, 3 is not directly applied to the edge portion E of the ceramic element 1. Thereby, the tolerance with respect to the bending of the mounting board | substrate P can be improved. Further, the convex portion 26 also has a function of attracting the bonding material 7 by capillary action, and has an effect of suppressing generation of voids due to contraction when the bonding material 7 is solidified. As for the height of the convex part 26, it is desirable to set to about 0.1-0.3 mm.

(Fifth embodiment)
FIG. 6A is a plan view of a surface mount type ceramic capacitor according to the fifth embodiment, and FIG. 6B is a cross-sectional view taken along the line VI-VI in FIG. The ceramic capacitor of the fifth embodiment is a modification of the ceramic capacitor of the fourth embodiment, and includes a disk-shaped ceramic element 1 and metal terminals 2 and 3 joined to the front and back of the ceramic element 1. And an insulating exterior material 4 covering a part of the ceramic element 1 and the metal terminals 2 and 3. 6A and 6B, the same parts and the same parts as those of the fourth embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  A circular hole 20a and a rectangular hole 20b are formed in the joint portion 20 of the metal terminal 2, and an annular convex portion 26 having a substantially conical cross-sectional shape protruding toward the ceramic element 1 is formed around the circular hole 20a. Is provided. A circular hole 30 a is formed in the joint portion 30 of the metal terminal 3, and an annular convex portion 26 having a substantially conical cross section protruding toward the ceramic element 1 is provided around the circular hole 30 a. Yes.

(Sixth embodiment)
FIG. 7A is a plan view of a surface mount type ceramic capacitor according to the sixth embodiment, and FIG. 7B is a cross-sectional view taken along the line VII-VII in FIG. The ceramic capacitor includes a disk-shaped ceramic element 1, metal terminals 2 and 3 bonded to the front and back of the ceramic element 1, and an insulating exterior material covering a part of the ceramic element 1 and the metal terminals 2 and 3. 4 is provided. The ceramic element 1 is the same as that described in the first embodiment, and a detailed description thereof is omitted.

  The metal terminal 2 extends substantially parallel to the surface 11 a and is bonded to the electrode 5, and the mounting portion 24 that extends parallel to the bonding portion 20 and is mounted on the mounting substrate P. And a relay portion 22 that connects the joint portion 20 and the mounting portion 24. A step 21 is formed at the joint 20. Similarly, the metal terminal 3 extends in parallel to the back surface 11b and is bonded to the electrode 6, and the mounting that extends in parallel to the bonding portion 30 and is mounted on the mounting substrate P. Part 34, and a relay part 32 that connects the joint part 30 and the mounting part 34. The relay part 32 is bent into a substantially inverted U shape. Furthermore, each of the joint portions 20 and 30 is provided with a plurality of substantially conical convex portions 26 protruding toward the ceramic element 1 side.

  The insulating exterior material 4 is provided so as to cover the ceramic element 1, the joint portion 20 and the relay portion 22 of the metal terminal 2, and the joint portion 30 and the relay portion 32 of the metal terminal 3. The mounting portions 24 and 34 of the metal terminals 2 and 3 are exposed from the insulating exterior material 4. A flat portion having a diameter of approximately 2.5 mm or more is provided on the upper surface of the insulating exterior material 4, and a portion projecting upward within a range having a diameter of approximately 4 mm or more in the same center as the flat portion is not provided. Thereby, a ceramic capacitor that can be attracted by an automatic mounting machine is obtained. In order to provide a flat portion with a diameter of approximately 2.5 mm or more on the upper surface of the insulating exterior material 4, a flat portion with a diameter of approximately 3.5 mm or more may be provided on the metal terminal 2. However, it is needless to say that the metal terminal 2 may have a convex portion 26 or a hole as long as it can be smoothed by the insulating exterior material 4.

  And in the part which the outer peripheral surface 11c of the ceramic substrate 1a and the relay part 22 of the metal terminal 2 oppose, the insulating exterior material 4 which coat | covers the outer peripheral surface 11c of the ceramic substrate 1a, and the relay part 22 of the metal terminal 2 are coat | covered A space S <b> 1 is formed between the insulating exterior material 4 to be formed. Similarly, in the portion where the outer peripheral surface 11c of the ceramic substrate 1a and the relay portion 32 of the metal terminal 3 face each other, the insulating exterior material 4 that covers the outer peripheral surface 11c of the ceramic substrate 1a and the relay portion 32 of the metal terminal 3 are provided. A space S2 is formed between the insulating exterior material 4 to be covered.

  The surface mount type ceramic capacitor having the above configuration is formed between the insulating exterior material 4 covering the outer peripheral surface 11 c of the ceramic element 1 and the insulating exterior material 4 covering the relay portion 22 of the metal terminal 2. The mounting portion 24 of the metal terminal 2 and the mounting portion 34 of the metal terminal 3 are formed by the space S1 formed between the space S1 formed and the insulating exterior material 4 covering the relay portion 32 of the metal terminal 3. The creeping distance of the insulating exterior material 4 between the two is increased, and creeping discharge when a high voltage is applied can be suppressed. Further, the spaces S1 and S2 have spring properties at the boundary portion between the joint portion 20 and the relay portion 22 of the metal terminal 2 and the boundary portion between the joint portion 30 and the relay portion 32 of the metal terminal 3. Mechanical stress when the substrate P is bent is applied to these boundary portions, and mechanical stress is not directly applied to the ceramic element 1. As a result, it is possible to obtain a ceramic capacitor in which mechanical stress when the mounting substrate P is bent is not directly applied to the ceramic element 1 and can prevent creeping discharge.

(Other embodiments)
In addition, this invention is not limited to the said embodiment, In the range of the summary, it changes variously. The ceramic electronic component may be a varistor or the like in addition to the capacitor.

DESCRIPTION OF SYMBOLS 1 Ceramic element 1a Ceramic substrate 2, 3 Metal terminal 4 Insulating exterior material 5, 6 Electrode 7 Joining material 11a Surface (1st main surface)
11b Back surface (second main surface)
11c Outer peripheral surface 20, 30 Joint portion 22, 32 Relay portion 24, 34 Mounting portion 26 Convex portion 61 Fillet S, S1, S2 Space

Claims (8)

A ceramic having a ceramic substrate having a first main surface and a second main surface facing each other and an outer peripheral surface, and a first electrode provided on the first main surface and a second electrode provided on the second main surface. Elements,
A first metal terminal joined to the first electrode;
A second metal terminal joined to the second electrode;
An insulating exterior material covering the ceramic element, a part of the first metal terminal and a part of the second metal terminal;
A ceramic electronic component comprising:
The first metal terminal extends parallel to the first main surface and is joined to the first electrode, and the first metal terminal extends parallel to the first joint and is mounted. A first mounting portion mounted on a substrate, and a first relay portion connecting the first joint portion and the first mounting portion,
The second metal terminal extends in parallel to the second main surface and joined to the second electrode, and extends in parallel to the second joint. A second mounting portion mounted on the mounting substrate; and a second relay portion connecting the second joint portion and the second mounting portion;
The insulating exterior material covers the ceramic element, the first joint portion, the first relay portion, and the second joint portion, and the first mounting portion and the second mounting portion are exposed. Provided as
In the portion where the outer peripheral surface of the ceramic substrate and the first relay portion of the first metal terminal face each other, the insulating exterior material covering the outer peripheral surface of the ceramic substrate and the first relay portion of the first metal terminal A space is formed between the insulating exterior material covering
Features ceramic electronic parts.   2. The ceramic electronic component according to claim 1, wherein the first electrode and the second electrode are provided on the entire surfaces of the first main surface and the second main surface, respectively.   A width dimension of the first joint portion of the first metal terminal is larger than a width dimension of the ceramic element, and an edge portion of the ceramic element recedes from an edge portion of the first joint portion in a plan view. The ceramic electronic component according to claim 1 or 2.   A fillet made of a bonding material for bonding the first electrode of the ceramic element and the first metal terminal is formed between the edge of the ceramic element and the first bonding portion, and the first electrode The ceramic electronic component according to claim 3, wherein the bonding material or the bonding material and the insulating exterior material are filled between the first bonding portion and the first bonding portion.   The minimum distance between the second electrode and the second metal terminal of the ceramic element and the first metal terminal is equal to or greater than the thickness dimension of the ceramic substrate. A ceramic electronic component according to any one of the above.   The ceramic electronic component according to any one of claims 1 to 5, wherein each of the first joint portion and the second joint portion has a convex portion protruding toward the ceramic element side. .   The ceramic electronic component according to claim 1, wherein the insulating exterior material is made of an epoxy-based powder resin.   A flat portion having a diameter of about 2.5 mm or more is provided on the upper surface of the insulating exterior material, and a portion protruding upward is provided within a range having a diameter of about 4 mm or more in the same center as the flat portion. The ceramic electronic component according to claim 1, wherein the ceramic electronic component is not provided.

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