FORM 2
THE PATENTS ACT, 1970
(39 OF 1970)
&
PATENTS RULES, 2006
COMPLETE SPECIFICATION (SECTION 10; RULE 13)
"CAPACITOR ASSEMBLY USED FOR PLASTIC FILM CAPACITORS"
ALCON ELECTRONICS PVT. LTD., A COMPANY INCORPORATED UNDER THE COMPANIES ACT, 1956, HAVING ITS REGD. OFFICE AT 34-B, MIDC, INPUSTRIAL ESTATE, STAPUR, NASHIK- 422 007, MAHARASHTRA, INDIA.
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE NATURE OF THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED

Technical Field:
The present invention relates to improvements in capacitors. Particularly, the present invention relates to improvements in plastic film capacitors used for dc, ac pulse / filter application.
Background:
Capacitors known in the prior art, which are used as plastic film capacitor are described with reference to figure 1, wherein the same numerals denote the same parts-and wherein:
Figure la) shows the schematic of the capacitor assembly known in the prior art, Figure lb) shows the cross-sectional view of the capacitor assembly known in the prior art.
As shown in figure 1, the capacitor assembly comprises of a capacitor element (1), first and second terminal regions (3a, 3b), first and second regions (2a, 2b), wherein the first and second regions are connected to respective first and second terminals regions by a respective flexible conductors (2,4). These flexible conductors are connected to die respective regions and respective terminal regions by a single contact. The second-flexible conductor (4) passes through the hollow centre plastic core (6).

The aforesaid assembly is encapsulated in a metal or plastic container (5). The hermetic sealing between the capacitor element (1) and container (5) is achieved by filling the empty region (7) with an epoxy resin.
Due to aforesaid construction, an electrical loop is formed between point 10 (a) and point 10(b). This loop offers a self inductance. The bigger the loop, the bigger is die self inductance. This self inductance of die capacitor causes Self heating of the capacitor at high frequency operation.
Therefore, there was a need to improve the heat dissipation in plastic film capacitors used for dc/ac pulse application / filter application. Earlier, in power electronics field, linear power supplies were used. In such power supplies ripple current requirements were not high. So heat dissipation was not critical parameter for capacitor.
Switch mode power supplies were being used in power electronics field. For such supplies, ripple current requirement is relatively high. To cater increased current requirement, capacitor's heat dissipation has to be more effective.
As mentioned in prior art, flexible conductors were used for terminations, which forms loop. Loop offers more self inductance and ultimately causes heating of die capacitor.

Object of the invention:
The present invention obviates the aforesaid drawbacks by providing a capacitor assembly, which reduces the self inductance of the termination.
In the present invention, dip drawn cup assembly made up of electro copper is being used as electrode. Cup surface is provided wim multiple punched C shaped cut to improve solderability. Particular arrangement reduces inductance considerably and improves heat dissipation.
Summary of the invention:
The present invention relates to a capacitor assembly used for plastic film capacitors comprising of capacitor element wherein a first cup electrode is connected to the first region of the capacitor element, a polypropylene cap is placed Over the first cup electrode, a second cup electrode is placed on the polypropylene cap, a bottom cup connected to the second region of the capacitor element wherein the second cup electrode and bottom cup are connected with copper stripe and a mica disc is connected to bottom cup.
Detailed description of the invention
The present invention will now be described with reference to Figure (2) and Figure (3)

Figure (2) (a) to (h) shows the schematic of all the parts of the capacitor assembly.
Figure (3) (a) to (d) shows the cross-sectional view of the capacitor assembly and assembled capacitor.
Figure (2) (a) shows capacitor element marked with terminal regions (1) and (2). As shown in Figure (2)(b), the first electrode (el) is connected to the first region of the capacitor element.
Thereafter, polypropylene cap is inserted to provide electrical insulation between electrodes (el) and (e2). Figure 2(c) shows die above arrangement. Figure 2 (d) shows second electrode (e2) cup placed exactly opposite to electrode (el) and on the polypropylene surface. Figure 2 (e) shows a bottom Cup connected to second region Of element.
Figure 2 (f) shows second electrode (e2) cup and bottom cup are connected with copper stripe. Figure 2(g) shows bottom side of the finish assembly.
Mica disc is affixed to the bottom cup with thermally conductive but electrically insulating compound, thereby reducing thermal impedance of die capacitor. Figure 2(h) shows the capacitor assembly.

The assembly is electrically isolated and sealed in an enclosure of any material as shown in Figure 3 (c) & (d). This enclosure has bottom stud for mounting capacitor on to a conduction cooling device.
The aforesaid construction reduces the self inductance of die terminations considerably.
Although the invention has been described in terms of particular embodiments and applications, one of ordinary skill in the art, in light of this teaching, can generate additional embodiments and modifications without departing from the spirit of or exceeding die scope of the claimed invention. It should be emphasized that the above-described embodiments of the present invention, particularly any "preferred" embodiments, are merely possible examples of the invention of implementations, merely set forth for a clear understanding of the principles of the invention. Accordingly, it is to be understood that die drawings and descriptions herein are preferred % way of example to facilitate comprehension of the invention and should not be construed to limit the scope thereof.

We'Claim:'
i. A capacitor assembly used for plastic film capacitors comprising of
(i) capacitor element with two terminal regions and two cup electrodes;
(ii) first cup electrode is connected to first terminal region;
(iii) a polypropylene cap placed over said first cup electrode;
(iv) a second cup electrode placed on said polypropylene cap;
(v) a bottom cup connected to second terminal region;
(Vi) said second cup electrode and bottom cup connected with copper
stripe; (vii) mica disc connected to bottom cup.
2. A capacitor assembly as claimed in Claim 1 wherein said bottom cup has plurality of punch outs for soldering purposes.
3. A capacitor assembly as claimed in Claim 2 wherein said punch outs are 'C -shaped'.
4. A capacitor assembly as claimed in any of the aforesaid claims which is used for dc or ac pulse application and filter application.
5. A capacitor assembly as herein described with reference to die drawings accompanying the specification,