JP2007234708A - Capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a capacitor which is raised in reliability and capable of suppressing the occurrence of a crack in the drawing-out part of the outside connecting terminals from a sealing resin, even when circumferential temperature is changed in the arrangement place of the capacitor. <P>SOLUTION: A capacitor element 1 is stored in a case 2 so as to be filled with the resin 3, and the outside connecting terminals 6, 7 are derived from the filling resin 3 to an outside concerning the capacitor. Notched parts 10 obtained by notching the outside connecting terminals 6, 7 are formed at contacts between the outside connecting terminals 6, 7 and the surface of the resin and in each adjacent position so as to be arcuately recessed from both the sides of the outside connecting terminals 6, 7. The filling resin 3 entering the notched parts 10 reinforce the restriction of a relative vertical movement concerning the outside connecting terminal 6, 7 and the filling resin 3. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a capacitor having a structure in which a capacitor element is housed in a case and filled with resin.

Capacitors having a structure in which a capacitor element is housed in a case and filled with resin are known (for example, Patent Document 1 and Patent Document 2). A schematic structure of this capacitor is shown in FIG. In the figure, reference numeral 21 denotes a capacitor element. The capacitor element 21 is housed in a case 22 opened upward, and is sealed with an epoxy resin 23 in this state. Metallicon electrodes 24, 25 are formed on the upper and lower surfaces of the capacitor element 21. External connection terminals 26, 27 are connected to the metallicon electrodes 24, 25 by soldering 28, and the external connection terminals 26, 27 are connected to each other. The lead is led out from the sealing resin 23 to the outside.
JP-A-2005-159107 Japanese Patent Laying-Open No. 2005-039058

  By the way, in the capacitor having the above-described structure, when the ambient temperature at the place where the capacitor is installed changes, cracks are generated in the portions where the external connection terminals 26 and 27 are drawn from the sealing resin 23 (arrow A portion in FIG. 2). May arise. This is because the coefficient of thermal expansion of each part differs due to the difference in the material of the capacitor element 21, the sealing resin 23, and the external connection terminals 26 and 27. In order to prevent this, the soft resin 23 may be used, but in that case, it is expected that there will be an inconvenience of increasing the cost.

  The present invention has been made to solve the above-described conventional problems, and its object is to crack the lead-out portion of the external connection terminal from the sealing resin even if the ambient temperature of the capacitor installation location changes. Therefore, it is possible to provide a capacitor with improved reliability.

  Therefore, the capacitor of the present invention is a capacitor in which the capacitor element 1 is housed in the case 2 and filled with the resin 3, and the external connection terminals 6 and 7 are led out from the filled resin 3 to the outside. 7 is characterized in that a constricted portion 10 having a smaller cross-sectional area than other portions is provided at a portion in contact with the resin surface and in the vicinity thereof.

  In the present invention, when the flat external connection terminals 6 and 7 are used, the external connection terminals 6 and 7 are notched so that the constricted portion 10 is recessed in an arc shape from both sides of the external connection terminals 6 and 7. It is formed as a notch 10 that has been cut.

  In addition, through holes 11 are provided at appropriate positions of the external connection terminals 6 and 7 so that the filling resin 3 enters the through holes 11.

  Further, the external connection terminals 6 and 7 are provided with through holes 12 in the portions 6 a and 7 a that are in contact with the metallicon electrodes 4 and 5 of the capacitor element 1, and the filling resin 3 is connected to the metallicon electrodes 4 and 5 through the through holes 12. I try to make contact.

  In the capacitor according to the present invention, the restriction of relative movement between the external connection terminal and the filling resin, for example, relative movement in the vertical direction in FIG. As a result, it is possible to suppress the occurrence of cracks in the lead-out portion of the external connection terminal from the sealing resin even if the ambient temperature of the capacitor installation location changes. Therefore, a capacitor with improved reliability can be obtained. Can be provided.

  Further, in the capacitor according to the present invention, a through hole is provided at an appropriate position of the external connection terminal, and the filling resin is intruded into the through hole, so that the restriction on relative movement between the external connection terminal and the filling resin is strengthened. As a result, the occurrence of cracks can be more effectively suppressed, and the reliability of the capacitor can be further improved.

  Furthermore, in the capacitor according to the present invention, the external connection terminal is provided with a through hole in a portion of the capacitor element that contacts the metallicon electrode, and the filling resin is in contact with the metallicon electrode through the through hole. Restriction of relative movement of terminals, filling resin, and metallicon electrodes has been strengthened. As a result, temperature deformation stress acting on metallicon electrodes can be reduced, cracks can be more effectively suppressed, and the reliability of capacitors can be further improved. .

  Next, specific embodiments of the capacitor of the present invention will be described in detail with reference to the drawings. In FIG. 1, reference numeral 1 denotes a capacitor element. This capacitor element 1 is housed in a case 2 that opens upward and is sealed with an epoxy resin 3 in this state. Metallicon electrodes 4 and 5 are formed on the upper and lower surfaces of the capacitor element 1 by, for example, zinc spraying, and flat external connection terminals 6 and 7 are connected to the metallicon electrodes 4 and 5 by soldering 8. The external connection terminals 6 and 7 are led out from the sealing resin 3 to the outside. The external connection terminal 6 connected to the upper metallicon electrode 4 is formed by integrally forming an electrode connection portion 6a, a lead-out portion 6b led out to the outside, and a connecting portion 6c for connecting them. . Similarly, the external connection terminal 7 connected to the lower metallicon electrode 5 is also integrally formed with an electrode connection portion 7a, a lead-out portion 7b led out to the outside, and a connecting portion 7c for connecting them. The external connection terminal 7 is electrically insulated from the upper metallicon electrode 4.

  As shown in FIG. 1 (b), in the external connection terminals 6 and 7, the lead-out portions 6b and 7b are located in the middle of the contact portion with the resin surface and in the vicinity thereof (filling A constricted portion 10 having a smaller cross-sectional area than other portions is provided in a portion drawn from the resin 3. In this case, the constricted portion 10 is formed as a cutout portion 10 in which the external connection terminals 6 and 7 are cut out so as to be recessed in an arc shape from both sides of the external connection terminals 6 and 7. The lower half of the notch 10 is embedded in the filling resin 3. Further, as shown in FIG. 1A, through holes 11 and 11 are formed in portions of the connecting portions 6c and 7c in the external connection terminals 6 and 7 facing the upper metallicon electrode 4 in the respective connecting portions 6c and 7c. The filling resin 3 is also allowed to enter the through holes 11 and 11. Further, as shown in FIG. 1A, a through hole 12 is formed in the electrode connecting portion 6a of the external connection terminal 6 connected to the upper metallicon electrode 4, and the filling resin 3 is passed through the through hole. The metallicon electrode 4 and the filling resin 3 are brought into close contact with each other. Although not shown, a through hole similar to the above is also formed in the electrode connection portion 7 a of the external connection terminal 7 connected to the lower metallicon electrode 5.

  In the capacitor described above, the relative movement between the external connection terminals 6 and 7 and the filling resin 3, for example, the relative movement in the vertical direction in FIG. As a result, it is possible to suppress the occurrence of cracks in the lead-out portions of the external connection terminals 6 and 7 from the sealing resin 3 even if the ambient temperature at the capacitor installation location is changed. A capacitor with improved reliability can be provided.

  In the capacitor, since the through holes 11 are provided in the connecting portions 6c and 7c of the external connection terminals 6 and 7, and the filling resin 3 is intruded into the through holes 11, the external connection terminals 6 and 7 and the filling resin As a result, the occurrence of cracks can be more effectively suppressed and the reliability of the capacitor can be further improved.

  Further, in the capacitor, the external connection terminals 6 and 7 are provided with through holes 12 in the portions 6a and 7a that are in contact with the metallicon electrodes 4 and 5 of the capacitor element 1. 4 and 5, the restriction of relative movement of the external connection terminals 6 and 7, the filling resin 3, and the metallicon electrodes 4 and 5 is strengthened. As a result, the temperature deformation acting on the metallicon electrodes 4 and 5 is enhanced. Stress can be reduced, cracks can be suppressed more effectively, and the reliability of the capacitor can be further improved.

  Although the specific embodiment of the capacitor of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention. . For example, in the above-described embodiment, the through hole 11 is provided in the connecting portions 6c and 7c of the external connection terminals 6 and 7, but this through hole 11 is embedded in the filling resin 3 in the lead-out portions 6b and 7b. You may provide in the part. Further, the filling resin 3 is not limited to the epoxy resin, and the metallicon electrodes 4 and 5 are not limited to the zinc spraying, and these materials can be variously changed.

It is a figure which shows the capacitor | condenser which is embodiment of this invention, (a) is a top view which shows the state before resin filling, (b) is sectional drawing after resin filling. It is a figure which shows the conventional capacitor | condenser, (a) is a top view which shows the state before resin filling, (b) is sectional drawing after resin filling.

Explanation of symbols

    1 .. Capacitor element 2 .. Case 3 .. Filling resin 4, 5 .. Metallicon electrode, 6, 7 .. External connection terminal, 8 .. Solder part, 10. ) 、 11 ・ ・ Through hole, 12 ・ ・ Through hole

Claims (4)

  The capacitor element (1) is housed in the case (2) and filled with the resin (3), and the external connection terminals (6) and (7) are led out from the filled resin (3) to the outside. In the connection terminals (6) and (7), a constriction portion (10) having a smaller cross-sectional area than other portions is provided at the contact portion with the resin surface and in the vicinity thereof.   The external connection terminals (6) and (7) are flat, and the constricted portion (10) is externally connected to the external connection terminals (6) and (7) so as to be recessed in an arc shape from both sides. 6. The capacitor according to claim 1, wherein the notch is formed as a notch (10).   3. A through hole (11) is provided at an appropriate position of the external connection terminal (6) (7), and the filling resin (3) is inserted into the through hole (11). Capacitor.   The external connection terminals (6) and (7) are provided with through holes (12) in portions (6 a) and (7 a) that are in contact with the metallicon electrodes (4) and (5) of the capacitor element 1. The capacitor according to any one of claims 1 to 3, wherein the filling resin (3) is brought into contact with the metallicon electrode (4) (5).