JPH0314043Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention is a capacitor element made into a flat shape by winding an anode foil and a cathode foil through a separator and pressing them together with a sealing member. This relates to a flat electrolytic capacitor built into a case.

[Conventional technology and problems] Conventionally, in this type of flat electrolytic capacitor, the capacitor element is pressed into a flat shape and impregnated with an electrolyte, and then the capacitor element is assembled into a flat case together with a sealing body. Due to this structure, the capacitor element inevitably swells after being assembled into the case. This swelling action has the disadvantage of increasing the so-called interpolar distance between the anode foil and the cathode foil, resulting in deterioration of the properties of the electrolytic capacitor.

On the other hand, as for the capacitor element inside the case, a fixing agent such as adhesive polypropylene is used to fix it to the case, but as the capacitor element becomes thinner and smaller, there is no space for filling the fixing agent. It is becoming difficult to fix it.

Furthermore, when assembling the sealing body into the flat case, it is necessary to position it correctly, which makes the work complicated.

Furthermore, such flat electrolytic capacitors usually have an explosion-proof groove formed at the bottom of the case, but the bottom of the case is strong enough to withstand the occurrence of gas inside the case. Since it did not deform, it did not operate even if the specified internal pressure was reached.

[Summary of the invention] However, the present invention forms a concave surface on the case for the purpose of suppressing the swelling of the capacitor element, fixing the capacitor element, and facilitating the positioning of the sealing body, and also forms a concave surface on this concave surface according to the standard. The present invention provides a flat electrolytic capacitor in which an explosion-proof groove is formed to provide accurate explosion-proof function.

[Example] Examples of the flat electrolytic capacitor according to the present invention will be described below with reference to the drawings.

That is, in the flat electrolytic capacitor 1,
The capacitor element 2 is formed into a flat shape by winding an anode foil and a cathode foil made of aluminum foil with a required separator made of electrolytic paper interposed therebetween and pressing them together. The separator or other insulating tape is wound around the outer periphery of the capacitor element 2 thus formed, so that it is electrically insulated.

Further, the bottomed flat case 3 having an opening surface 3e on one side is formed using an aluminum material or the like, and from the opening side of the flat case 3 except for the vicinity of the opening surface 3e to the vicinity of the bottom portion 3g. On the flat side surface 3f leading to the step part 3b, the sealing body 4 to be incorporated can be locked via its tip edge 4a.
and the capacitor element 2
A concave surface 3a is formed that enables the formation of a space having a width approximately equal to the thickness in the length direction.

A linear explosion-proof groove 5 is formed in the center of the concave surface 3a in a direction intersecting the opening surface 3e of the flat case 3.

In addition, in the present invention, the concave surface 3a can be formed only on one side of the case 3, or can be formed on both sides, and the linear explosion-proof groove 5 is formed so that the concave surface 3a is When it is formed on only one side of the case 3, it can be formed on the concave surface 3a, and when it is formed on both sides, it can be formed on either side or both sides.

On the other hand, the capacitor element 2 is incorporated into the case 3 together with the sealing body 4 after being impregnated with a required electrolytic solution. During this installation, the sealing body 4 is held in contact with the step portion 3b defining the concave surface 3a via its tip edge 4a, and is properly positioned within the case 3.

After the capacitor element 2 and the sealing body 4 are properly positioned and assembled in the case 3 in this way, the open end of the case 3 is curled 3c, and the sealing body portion of the case 3 is drawn 3d. be done.

[Effects of the invention] As described above, according to the invention, the capacitor element 2 is supported by coming into contact with the concave surface 3a formed in the case 3, so that it can be easily fixed within the case 3. . Moreover, capacitor element 2
The sealing body 4, which is also incorporated into the case 3, can be engaged with the stepped portion 3b defining the concave surface 3a via its tip edge 4a, so that its positioning can be easily performed.

In addition, in the case where the capacitor element 2 swells, the concave surface 3a can suppress the swelling, thereby preventing the space ratio inside the case 3 from decreasing. Furthermore, this concave surface 3a is
In addition to eliminating the need for a fixing agent for fixing the capacitor element 2, it is possible to improve the strength of the case 3 itself and prevent it from deforming.

Furthermore, when gas is generated in the case 3, the linear explosion-proof groove 5 formed in the concave surface 3a located on the side surface of the case 3 is activated, and as a result, the conventional explosion-proof groove is formed in the bottom of the case. Its operation can be ensured compared to other products.

Moreover, since the linear explosion-proof groove 5 is formed with a simple single-line structure, the explosion-proof activation point can be standardized by adjusting its length, groove width, and groove depth as appropriate. It is possible to easily reduce variations in product quality.

[Brief explanation of the drawing]

FIG. 1 is a developed view of a flat electrolytic capacitor according to the present invention, FIG. 2 is a longitudinal sectional view of the flat electrolytic capacitor, and FIG. 3 is a partially enlarged sectional view of a case. In the figure, 1...Flat type electrolytic capacitor, 2...Capacitor element, 3...Flat type case, 3a...Concave surface, 3b...Step part, 3e...Opening surface, 3f...Side surface, 3g...Bottom part , 4... Sealing body, 4a... Tip edge, 5... Straight explosion-proof groove.

Claims (1)

[Scope of utility model registration request] In a flat electrolytic capacitor in which an anode foil and a cathode foil are wound through a separator and a flat capacitor element is assembled together with a sealing member in a flat case, the opening side of the flat case except for the vicinity of the opening surface. A flat side surface extending from the bottom to the vicinity of the bottom is defined by a stepped portion that allows the sealing body to be incorporated to be locked via its tip edge, and
A concave surface is provided that enables the formation of a space having a width that substantially matches the thickness in the length direction of the capacitor element, and a concave surface is provided at the center of the concave surface in a direction that intersects with the opening surface of the flat case. A flat electrolytic capacitor characterized by having a single straight explosion-proof groove.