Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
  • H01G9/00—Electrolytic capacitors, rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices; Processes of their manufacture
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
  • H01G9/00—Electrolytic capacitors, rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices; Processes of their manufacture
  • H01G9/004—Details
  • H01G9/008—Terminals
  • H01G9/012—Terminals specially adapted for solid capacitors

Definitions

• the invention relates to a capacitor with a capacitance which comprises an anode body with a dielectric layer and a cathode layer.
• the capacitance is encased in a housing which has an upper side and a lower side.
• the capacitor has an anode conductor which contacts the anode body and which is connected to an anode contact which has a contact section arranged on the underside of the housing.
• the capacitor has a cathode conductor, which contacts the cathode layer.
• capacitors of the type mentioned are known, which are tantalum electrolytic capacitors in chip design.
• the known capacitors have a cathode conductor, which is bent several times within the housing of the capacitor.
• a tantalum wire is sintered into the anode body, which is welded to an anode connecting wire. The welding is inside the housing.
• capacitor powder of a higher capacity for the anode body there is the possibility of using capacitor powder of a higher capacity for the anode body, or of increasing the effective volume of use of the capacity.
• the known capacitor has the disadvantage that due to the multiple bend of the cathode conductor within the housing, a considerable volume of the housing is used for the cathode conductor. Likewise, a considerable volume of the housing is used for the weld connection between the tantalum wire and the anode connecting wire. In relation to the external dimensions of the housing, only a relatively small anode body can thus be installed in the housing with a predetermined size, which accordingly also has a small capacity or a small CV product.
• JP 08 124 804 AA discloses a capacitor of the type mentioned at the outset, in which the cathode conductor is led straight out of the housing from the top of the anode body.
• the anode conductor is still welded inside the housing to an anode contact plate, which is bent several times within the housing.
• This capacitor has the disadvantage that a relatively large housing volume is necessary in order to guide the cathode conductor or the anode conductor away from the anode body onto the underside of the housing. Accordingly, the known capacitor has a small usable volume.
• the aim of the present invention is therefore to provide a capacitor with an increased usable volume.
• a capacitor is specified with a capacitance which comprises an anode body with a dielectric layer and a cathode layer and which is enveloped by a housing with an upper side and a lower side.
• the capacitor comprises an anode conductor which contacts the anode body and which is connected to an anode contact which has a contact arranged on the underside of the housing.
• the cathode conductor is led out of the housing.
• the cathode conductor is a sheet metal that has holes within the housing.
• the housing is made of a castable material that fills the holes in the sheet. This creates an intimate connection between the cathode conductor and the housing.
• a capacitor whose cathode conductor is attached to the top of the capacitance is particularly advantageous.
• the cathode conductor runs in a straight line inside the housing and is accordingly led straight out of the housing. Outside the housing, the cathode conductor is electrically conductively connected to a cathode contact arranged on the underside of the housing.
• the capacitor has the advantage that the holes in the sheet metal filled with the housing material create an intimate connection between the housing material and the cathode conductor, as a result of which only a small wall thickness on the Top of the case is required. This effectively increases the usable volume of the condenser.
• the capacitor also has the advantage that the risk of the top surface of the housing being destroyed by the bending forces which occur is reduced in the event of a subsequent bending operation of the cathode conductor after completion of the housing.
• the anode conductor can be a wire which is led out laterally from the inside of the anode body.
• a wire can, for example, be a tantalum wire that is tantalum powder, which is pressed around the wire and then sintered. This creates a porous sintered body as an anode body, which enables the production of a capacitor with a very large capacitance.
• anode contact within the housing is contacted with an anode conductor, which is preferably led out of the housing on the side of the housing opposite the cathode conductor and at a height which essentially corresponds to the height at which the cathode conductor is led out of the housing ,
• the connection between the anode conductor and the anode contact can preferably be made by welding.
• a capacitor is also specified, having a capacitance, which comprises an anode body with a dielectric layer and a cathode layer and which is encased by a housing with an upper side and a lower side.
• the capacitor comprises an anode conductor which contacts the anode body and which is connected to an anode contact which has a contact section arranged on the underside of the housing, and furthermore a cathode conductor which contacts the cathode layer.
• the cathode conductor runs in a straight line inside the housing and is accordingly led straight out of the housing. Outside the housing, the cathode conductor is electrically conductively connected to a cathode contact arranged on the underside of the housing.
• the anode conductor and the anode contact of the capacitor are integral components of an anode sheet which is led out laterally from the inside of the anode body and whose end section runs along the underside of the housing and forms a contact section.
• the cathode conductor can be attached to the top of the capacitance.
• Such a capacitor has the advantage that welding within the housing between an anode ter and an anode plate can be omitted, whereby the housing wall can be made thinner and at the same time the useful volume of the capacitor is increased.
• Such a capacitor also has the advantage that it can be produced relatively easily by applying a tantalum paste to a tantalum sheet and then sintering. In particular, pressing a powder around a wire is no longer necessary.
• An anode conductor in the form of a sheet also has the advantage that there is a large contact area between the anode conductor and the anode body, whereby the internal resistance of the capacitor can be effectively reduced.
• the anode sheet preferably runs straight within the housing and is bent on the outside of the housing around the housing. The end section of the anode sheet runs along the underside of the housing and forms the contact section there.
• the contact section formed by the anode sheet must still be made solderable.
• tantalum or niobium can be considered for the anode conductor. These materials are relatively difficult to solder.
• the contact section running on the underside of the housing can be made solderable, for example, by applying a metal-containing layer.
• Such a capacitor also has the advantage that fewer individual components are used, as a result of which the variety of materials and the effort required for this, for example for soldering the anode conductor and anode contact, are eliminated.
• the cathode conductor is a sheet metal which is bent around the outside of the housing and around which the end section of the cathode conductor runs along the bottom of the housing and forms the cathode contact.
• Such a construction of the capacitor according to the invention has the advantage that the provision of an SMD-capable capacitor is possible with a cathode contact on the underside of the housing.
• the capacitor has the advantage that due to the absence of bends in the cathode conductor inside the housing, it has a very large usable volume inside the housing. As a result, an anode body with a large capacity or with a correspondingly large CxV value can be installed for a given housing dimension. Conversely, the capacitor can be reduced for a given CxV value.
• the capacitor according to the invention thus has a reduced space requirement with the CV product remaining the same.
• the reduction in the space requirement relates in particular to the lateral expansion, that is to say the expansion of the capacitor parallel to the top or bottom of the housing.
• the housing can be produced by molding the capacity with an epoxy resin.
• two injection molds each with a recess, are usually placed one above the other in such a way that a cavity is created which specifies the shape of the housing to be produced.
• Cathode arrester or the anode arrester are led out of the housing to be produced between the injection molds. If the cathode arrester and the anode arrester are now led out of the housing to be produced at the same height, injection molds with a very simple geometry, in particular with a respective flat surface, can be used.
• a capacitor which is produced by extrusion coating a capacitance provided with anode arrester and cathode arrester with a castable material forming the housing and subsequent bending of the cathode conductor led out of the housing and the anode contact led out of the housing.
• a capacitor has the advantage that it can be manufactured in a simple manner according to a standard process. Furthermore, such a capacitor has the advantage that the housing is not destroyed even after subsequent bending.
• the underside of the housing has a mounting surface, the height of which is selected in relation to the anode contact or in relation to the cathode contact so that it is suitable for gluing the housing onto a printed circuit board as part of a surface mounting technique.
• a capacitor has the advantage that it can be used as an SMD (Surface Mounted Device).
• a suitable arrangement of the mounting surface on the underside of the housing with respect to the anode contact or cathode contact could consist, for example, that the mounting surface lies in one plane with the underside of the cathode contact and the underside of the anode contact.
• This can advantageously be achieved by designing the underside of the housing in the form of a step, wherein in the sections of the housing which are elevated compared to a printed circuit board. the contacts (anode contact or cathode contact) are arranged on the underside.
• such a capacitor has the advantage that it corresponds to the standardized design with the name "Low Profile C".
• Low Profile C due to the absence of a bend in the cathode conductor, a large proportion of the length of the capacitor can be used for the capacitance.
• Figure 1 shows an example of a capacitor according to the invention in schematic cross section.
• Figure 2 shows an example of another capacitor according to the invention in schematic cross section.
• FIG. 3 shows an example of a cathode arrester for use in a capacitor according to the invention.
• FIG. 1 shows a capacitor with a capacitance 1, which is formed by an anode body 2, a dielectric layer 3 and a cathode layer 4.
• the anode body 2 is a porous sintered body which contains tantalum.
• the sintered body is surrounded by a dielectric layer 3, which contains tantalum pentoxide.
• the dielectric layer 3 in turn is surrounded by a cathode layer 4, which consists of graphite.
• the capacitance 1 is encased in a housing 5, which has a top 6 and a bottom 7.
• the housing 5 is made of epoxy resin and is produced by injection molding.
• capacitor shown in Figure 1 has one
• Anode conductor 8 which contacts the anode body 2.
• the anode conductor 8 is a tantalum wire, which is partially encapsulated by the tantalum powder of the anode body 2.
• the anode conductor 8 is furthermore led laterally out of the anode body 2 to an anode contact 9, which is a sheet made of a nickel / iron alloy. This sheet is made solderable with a copper or tin / lead coating.
• the invention can be implemented with any material forming a suitable porous sintered body and is not restricted to tantalum.
• the anode contact 9 has a contact section 10 which is arranged on the underside 7 of the housing 5. Furthermore, a cathode conductor 11 is fastened in an electrically conductive manner on the cathode layer 4 by means of a conductive adhesive 16.
• the cathode conductor 11 is a sheet made of an iron / nickel alloy, which has been made solderable by a corresponding coating. However, any other suitable material that is electrically conductive and solderable can also be used.
• the cathode conductor 11 contacts the cathode layer 4 and is at the same time attached to it.
• the cathode arrester 11 is straight and laterally led out of the housing 5, that is to say that the cathode arrester 11 runs straight within the housing 5 and has no curvatures or curves.
• the cathode conductor 11 is bent downward along the housing 5 around the housing 5 and forms a capacitor on the underside of the housing 5.
• thodentitle 12 which is suitable for soldering the capacitor on a circuit board.
• the invention is not limited to tantalum systems, but can be implemented with all other valve metals.
• the anode contact 9 is fastened to the anode conductor 8 by welding, a welding bead 17 being produced.
• the underside 7 of the housing 5 is stepped inwards again, so that an adhesive surface 15 is created, with its
• the capacitor can be glued to a printed circuit board, after which the soldering process then takes place, for example by means of wave soldering.
• the object shown in Figure 2 largely corresponds to the object shown in Figure 1. However, it differs in the design of the anode arrester.
• the anode conductor according to FIG. 2 is combined in one piece with the anode contact to form an anode plate 14 which contacts the anode body 2.
• This anode sheet 14 can be a tantalum sheet, for example, when using an anode body made of tantalum.
• the tantalum sheet can be coated with a tantalum paste and then sintered, whereby the anode body 2 is formed.
• the anode sheet 14 is led out laterally from the inside of the anode body 2 and runs straight within the housing 5 and is bent around the housing 5. As a result, in comparison with the object shown in FIG. 1, even more space can be saved in the lateral direction, since there is no need for further bends within the housing 5.
• the end section of the anode sheet 14 forms on the underside 7 of the housing 5 the contact section 10 which is suitable for soldering the capacitor onto a printed circuit board.
• FIG. 3 shows the design of a cathode conductor 11 in the form of a sheet which has holes 13. When the capacitance is encapsulated, these holes 13 can be filled with epoxy resin or another pourable material, which improves the mechanical stability of the cathode conductor 11 within the housing.

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• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Fixed Capacitors And Capacitor Manufacturing Machines (AREA)
• Thermistors And Varistors (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=7663948

Family Applications (1)

Country Status (11)

Families Citing this family (15)

Family Cites Families (11)

• 2000
  • 2000-11-20 DE DE10057488A patent/DE10057488B4/de not_active Expired - Fee Related
• 2001
  • 2001-11-20 WO PCT/DE2001/004351 patent/WO2002041344A1/de not_active Ceased
  • 2001-11-20 AU AU2002215863A patent/AU2002215863A1/en not_active Abandoned
  • 2001-11-20 IL IL15594601A patent/IL155946A0/xx unknown
  • 2001-11-20 EP EP01996874A patent/EP1336183A1/de not_active Withdrawn
  • 2001-11-20 KR KR10-2003-7006657A patent/KR20030084899A/ko not_active Withdrawn
  • 2001-11-20 US US10/432,449 patent/US6891716B2/en not_active Expired - Fee Related
  • 2001-11-20 JP JP2002543460A patent/JP2004523102A/ja active Pending
  • 2001-11-20 CZ CZ20031704A patent/CZ20031704A3/cs unknown
  • 2001-11-20 TW TW090128676A patent/TW541550B/zh not_active IP Right Cessation
  • 2001-11-20 CN CNA018191762A patent/CN1507642A/zh active Pending

Non-Patent Citations (1)

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