DE102006005832A1 - Capacitor has capacitor winding, which is arranged in housing, comprising conductive winding layer, where distance of later welding area to outer surface of housing is larger than distance of former welding area to outer surface of housing - Google Patents

Abstract

It is a capacitor with a housing and disposed therein Capacitor winding (5) specified, the winding layers comprises, wherein the winding layers one above the other folded over and in at least one for external welding through the housing inaccessible Area welded together are.

Description

A double-layer capacitor in which an electrode pad of the capacitor winding is contacted by the lid of the housing, z. B. from the document DE 202 04 027 U1 known.

A to be solved Task is to use a capacitor with a low-impedance Specify contact of a capacitor winding. Another task The invention is a method for producing such Specify double-layer capacitor.

It is a capacitor with a housing and disposed therein Capacitor winding specified, comprising conductive winding layers, wherein the winding layers one above the other folded and in at least one - preferably for an external welding through the housing through inaccessible area welded together are.

Under the winding layers are one above the other laid windings of rolled up to a coil electrode pad to understand.

Of the for one External welding inaccessible Area is z. B. nearby (preferably below) an area with increased housing thickness. The area can but also nearby a kink in the housing lie. In this welding area are Although the winding layers with each other, but preferably not with the housing welded.

Of the below the area with elevated case thickness lying welding area is at a given welding power for external welding through the housing inaccessible, being this welding power against z. B. for welding other areas of the housing is sufficient with the capacitor winding.

The Thickness of the housing in the for the external welding inaccessible Welding area exceeds the one in one for the external welding accessible Range preferably by at least a factor of two.

Of the Capacitor winding comprises a first and a second electrode pad, which are electrically isolated from each other by means of a separating layer. The winding layers comprise first winding layers which are a first Associated electrode pad of the coil, and second winding layers, which are associated with a second electrode pad of the coil.

The casing includes a housing cup and a lid. The capacitor winding is in the housing cup arranged. In the capacitor winding, a core tube is preferably arranged.

In at least one first welding area are protruding Regions of the winding layers of the first Elektrodenbelags together and welded to the lid. In at least one second welding area are protruding Regions of the winding layers of the first Elektrodenbelags together welded. In the second welding area Although the winding layers are preferably together, they are not with the housing welded. The distance of the winding end face to the outer surface of the housing is in the second welding area greater than in the first welding area, so that the second welding area for one welding through the lid is not suitable. The distance to the outer surface in the second welding area is preferably at least twice the distance in the first welding area.

The Thickness of the lid over exceeds the second welding area preferably the one above the first welding area. Possible but is also that the second welding area through an air gap spaced from the lid and therefore for the welding of Outside inaccessible is. In this case, there is no direct contact of the coil to Casing.

Under the second welding area is in particular a lid-facing frontal area to understand the capacitor winding, in contrast to the first Area for the weld from the outside through the lid is not accessible. A second welding area is preferably adjacent to an inwardly facing edge of the first welding area at. Another second welding area preferably adjoins an outwardly facing edge of the first Weld area.

It it is possible, in particular the winding layers facing the core tube and / or the outermost ones Wrapping layers to be welded together using the usual Welding power density due to a relatively high thickness of the overlying lid portions for one welding inaccessible through the lid are.

Out the fact that the winding layers including the terminal winding layers through a frontal weld shorted together, results in a low ESR value (ESR = Electrical Serial Resistance) and a relatively high power density of the capacitor.

The capacitor winding has a second electrode covering comprising several winding layers, wherein according to an advantageous variant protruding portions of the winding layers of the second electrode covering are welded together in at least one third welding area and with the bottom of the housing cup. In at least one fourth welding region, projecting regions of the winding layers of the second electrode coating are welded together, but not welded to the bottom of the housing cup. The thickness of the bottom of the housing cup over the fourth weld area preferably exceeds that above the third weld area.

Preferably are at least two out of five to the side wall of the housing cup facing layers of the respective electrode coating their protruding Areas welded together. Preferably, in at least two out of five winding layers facing the core tube the respective electrode coating their protruding areas together welded.

The Winding layers of the respective electrode coating can by means of laser welding welded together become. Other welding methods but also come into consideration.

Of the Winding a double-layer capacitor has two electrode pads and a interposed therebetween, electrically insulating separating layer. The winding layers of a specific electrode associated Electrode pads are preferably on the corresponding front side of the roll over the insulating release layer addition. The capacitor winding is in a housing mug angeord with a lid. In the cover can bulges (beads) be formed in the form of a tub, which is to the protruding Parts of the electrode pad produce a pressure contact. The floor the bead is preferably thinner as their sidewalls and includes the first welding area. The side walls include the second welding area. The second welding areas lie especially outside of the relatively thin-walled Bottom of the bead.

It will be added electrical and mechanical contact between the lid (in Area of the beads) and some winding layers of the electrode covering z. B. by spot welding means generated by a laser. By so formed cross connections between different winding layers of the capacitor winding become current paths kept low in the electrode coating.

• – überstehende Bereiche von Wickelschichten eines Kondensatorwickels werden übereinander umgelegt und miteinander verschweißt,
• – der Kondensatorwickel wird in einem Gehäuse platziert und die Wickelschichten stirnseitig mit dem Gehäuse verschweißt.

Furthermore, the method for producing the above-described double-layer capacitor is given. This method comprises the steps:

• - protruding areas of winding layers of a capacitor winding are folded over each other and welded together,
• - The capacitor winding is placed in a housing and the winding layers welded frontally to the housing.

in the Below are advantageous embodiments with reference to schematic and not to scale Figures explained. Show it:

1 in cross-section a capacitor with a capacitor winding whose winding layer are welded together;

2 the top view of the lid of the capacitor according to the 1 ;

3 the top view of the capacitor winding, with the lid of the capacitor according to the 1 and 2 is welded.

In 1 is a capacitor with a capacitor winding 5 shown, which is arranged in a housing. In the capacitor winding 5 is a core tube 6 arranged.

The housing includes a housing cup 1 and a lid 2 , with which the housing cup is sealed. The lid 2 is from the housing mug 1 z. B. electrically insulated by means of a rubber seal.

The lid 2 has an external connection 20 on, which may be provided for electrical connection to another capacitor by means of an electrically conductive connection element. The external connection 20 is the first external connection 20 provided of the capacitor.

The floor 10 of the housing cup 1 serves as the second external connection of the capacitor. Both external connections are used for external contacting in the 1 not shown electrode pads of the capacitor winding 5 ,

The in 3 shown first electrode coating 3 the capacitor winding 5 includes first winding layers. The second electrode coating of the capacitor winding 5 comprises second winding layers which are electrically insulated from the first winding layers. The winding layers of a variety are preferably folded over one another and welded together.

The lid 2 has a bead 41 or more, e.g. B. - as in 2 shown - three such beads 41 . 42 . 43 on, each contact the capacitor winding electrically. Because the beads 41 . 42 . 43 are preferably formed substantially identical, only the bead 41 and her connection to the wrap 5 described.

The bead 41 has the shape of a tub with a bottom and side walls. The bottom of the bead 41 is preferably relatively thin-walled with respect to its side walls. In the region of the preferably flat bead bottom, the cover touches the winding layers of the capacitor winding and is in at least a first welding region 21 welded with these. The first welding area 21 includes at least one spot weld. In the variant according to the 2 For example, indicated that the weld between the winding and the lid in two welds 21 . 22 . 23 per bead occurs. The welding of the lid and the capacitor winding is preferably carried out by means of an external welding, ie the welding through the lid.

In the 1 you can see that the sidewalls of the bead 41 compared with the bead bottom are relatively thick walls, with their wall thickness exceeds the wall thickness of the soil. In the areas which are arranged below the relatively thick-walled areas of the housing or the cover, the distance between the surface of the housing and the upper end side of the coil is 5 larger than in the winding directly contacting and provided for the external welding first welding areas 21 . 22 . 23 ,

But even with the same wall thickness, the side walls of the bead can not be perpendicular to their bottom, but be inclined, with the distance between the surface of the lid 2 and the upper end side of the roll 5 Also larger than in the intended for the external welding first welding areas 21 . 22 . 23 , Due to the greater distance, such areas are the end face of the roll 5 , which are below the sidewalls of the beads 41 . 42 . 43 are not accessible for external welding.

Therefore, the wound layers to be welded together and in particular z. B. three to five terminal winding layers welded together before closing the housing. It will be - in the 1 arranged below the side walls of the beads - second welding areas 71 . 72 formed, which are not suitable for external welding.

In the second welding area 71 are at least two of the core tube 6 clever terminal first winding layers welded together. In the second welding area 72 are at least two of the housing cup 1 clever terminal first winding layers welded together.

The first winding layers are the first electrode covering 3 assigned in 3 is shown. In 3 are those in the crimps 41 . 42 . 43 arranged welds 21 . 22 . 23 shown in which the lid 2 with the first electrode coating 3 of the roll 5 is welded.

The said in connection with the connection of the first winding layers of the capacitor winding with the lid applies equally well for the connection of the second winding layers with the housing bottom 10 , The greater distance between the bottom of the housing cup 1 and the bottom of the roll 5 can in some areas z. B. due to bulges or thickening of the housing bottom 10 arise, so that these areas for a weld from the outside are not accessible. As for the lid 2 also applies to the housing bottom, that it can have beads, in which welding areas are arranged.

The External welding or the welding The winding layers can not only pointwise, but along welding lines or take place over a large area.

1

housing cup

10

ground of the housing cup

2

cover

20

capacitor terminal

21 22, 23

first sweat rich

3

first electrode coating of the capacitor winding 5

41 42, 43

beading

5

capacitor winding

6

core tube

71, 72

second welding areas

Claims (13)

Capacitor - comprising a housing and a capacitor winding arranged therein ( 5 ), which comprises conductive winding layers, - wherein the winding layers in at least one first welding region ( 21 . 22 . 23 ) with the housing ( 5 ), wherein the winding layers are folded over one another and in at least one second welding region ( 71 . 72 ) are welded together, - wherein the distance of the second welding area ( 71 . 72 ) to the outer surface of the housing ( 5 ) is greater than the distance of the first welding area ( 21 . 22 . 23 ) to the outer surface of the housing ( 5 ). Capacitor according to claim 1, - wherein the second welding region ( 71 . 72 ) is disposed in an area with increased housing thickness, which is inaccessible for external welding through the housing. Capacitor according to claim 2, - wherein the wall thickness of the second welding area ( 71 . 72 ) at least twice the wall thickness of the first welding area ( 21 . 22 . 23 ) is. A capacitor according to claim 1, - wherein the housing comprises a housing cup ( 1 ) and a lid ( 2 ), wherein the capacitor winding ( 5 ) in the housing cup ( 1 ), wherein the winding layers comprise first winding layers, which in the second welding region ( 71 . 72 ) with the lid ( 2 ) Capacitor according to claim 4, - wherein the winding layers comprise second winding layers, which in the further second welding region with the housing cup ( 1 ) are welded. Capacitor according to one of claims 1 to 5, - wherein at a predetermined welding power of the first welding area ( 21 . 22 . 23 ) accessible for welding through the housing and the second welding area ( 71 . 72 ) is not accessible for such a weld. Capacitor according to one of claims 1 to 6, - in which at least two out of five to the side wall of the housing skilled winding layers their overhanging Areas are welded together. Capacitor according to one of Claims 1 to 7, - in the capacitor winding ( 5 ) a core tube ( 6 ), wherein at least two out of five to the core tube ( 6 ) Wrapped winding layers their protruding areas are welded together. Capacitor according to one of claims 1 to 8, - in which to weld together Winding layers are welded together by laser welding. Capacitor according to one of claims 4 to 9, - wherein the lid ( 2 ) Having relatively thin-walled bottom walls and relatively thick-walled side walls, - the area accessible for external welding being arranged at the bottom of these corrugations, - the area which is inaccessible to external welding being arranged below side walls of these corrugations. Capacitor according to one of Claims 1 to 9, - in the second welding region ( 71 . 72 ) no direct contact of the coil to the housing ( 5 ) consists. Process for producing a double-layer capacitor, comprising the steps of: - projecting regions of winding layers of a capacitor winding ( 5 ) are folded over each other and welded together, - the capacitor winding ( 5 ) is placed in a housing and the winding layers welded frontally to the housing. The method of claim 12, wherein the winding layers by means of a laser welding welded together become.