CA1093166A - Metallized film capacitors - Google Patents
Metallized film capacitorsInfo
- Publication number
- CA1093166A CA1093166A CA305,939A CA305939A CA1093166A CA 1093166 A CA1093166 A CA 1093166A CA 305939 A CA305939 A CA 305939A CA 1093166 A CA1093166 A CA 1093166A
- Authority
- CA
- Canada
- Prior art keywords
- metallized
- capacitor
- dielectric layer
- layer
- segment
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000003990 capacitor Substances 0.000 title claims abstract description 192
- 239000011104 metalized film Substances 0.000 title abstract 2
- 239000007921 spray Substances 0.000 claims abstract description 50
- 239000000463 material Substances 0.000 claims abstract description 23
- 239000003989 dielectric material Substances 0.000 claims abstract description 13
- 238000004804 winding Methods 0.000 claims description 26
- 238000004519 manufacturing process Methods 0.000 abstract description 9
- 239000007858 starting material Substances 0.000 abstract description 2
- 238000000034 method Methods 0.000 description 13
- 239000010408 film Substances 0.000 description 8
- 238000010276 construction Methods 0.000 description 7
- 230000035515 penetration Effects 0.000 description 5
- 239000002184 metal Substances 0.000 description 4
- 239000004793 Polystyrene Substances 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 229920000515 polycarbonate Polymers 0.000 description 3
- 239000004417 polycarbonate Substances 0.000 description 3
- 229920000728 polyester Polymers 0.000 description 3
- 238000003825 pressing Methods 0.000 description 3
- 239000011253 protective coating Substances 0.000 description 3
- 238000005476 soldering Methods 0.000 description 3
- 238000005507 spraying Methods 0.000 description 3
- 239000010409 thin film Substances 0.000 description 3
- 239000004743 Polypropylene Substances 0.000 description 2
- 239000011888 foil Substances 0.000 description 2
- 239000013528 metallic particle Substances 0.000 description 2
- -1 polypropylene Polymers 0.000 description 2
- 229920001155 polypropylene Polymers 0.000 description 2
- 229920002223 polystyrene Polymers 0.000 description 2
- YUBJPYNSGLJZPQ-UHFFFAOYSA-N Dithiopyr Chemical compound CSC(=O)C1=C(C(F)F)N=C(C(F)(F)F)C(C(=O)SC)=C1CC(C)C YUBJPYNSGLJZPQ-UHFFFAOYSA-N 0.000 description 1
- 241000543375 Sideroxylon Species 0.000 description 1
- 239000003985 ceramic capacitor Substances 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 230000000873 masking effect Effects 0.000 description 1
- 239000002923 metal particle Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
- H01G4/00—Fixed capacitors; Processes of their manufacture
- H01G4/002—Details
- H01G4/228—Terminals
- H01G4/232—Terminals electrically connecting two or more layers of a stacked or rolled capacitor
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
- H01G4/00—Fixed capacitors; Processes of their manufacture
- H01G4/26—Folded capacitors
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
- H01G4/00—Fixed capacitors; Processes of their manufacture
- H01G4/32—Wound capacitors
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Fixed Capacitors And Capacitor Manufacturing Machines (AREA)
- Ceramic Capacitors (AREA)
Abstract
METALLIZED FILM CAPACITORS
Abstract of the Disclosure The present invention provides a product which has all of the many advantages of pleated, wound, electrical capacitors and also has the added advantage that it may be manufactured with commercially available metallized die-lectric materials. A further advantage of the present invention is that the same basic starting materials may be used to manufacture capacitors that have a number of different pleating combinations. Thus, the invention provides for an electrical capacitor segment which comprises a dielectric layer having a center line, a first metallized electrode layer applied to one side of the dielectric layer so that an unmetallized margin ex-tends along each edge of a pair of parallel edges of the di-electric layer, and a second metallized electrode layer applied to the other side of the dielectric layer so that an unmetallized area is located adjacent the second metallized electrode layer.
The dielectric layer is pleated once along the unmetallized areas off of the center line so that one edge of the margin containing edges extends beyond the other of the edges along the same end of the capacitor segment and metallized spray material in contact with the second electrode layer.
Abstract of the Disclosure The present invention provides a product which has all of the many advantages of pleated, wound, electrical capacitors and also has the added advantage that it may be manufactured with commercially available metallized die-lectric materials. A further advantage of the present invention is that the same basic starting materials may be used to manufacture capacitors that have a number of different pleating combinations. Thus, the invention provides for an electrical capacitor segment which comprises a dielectric layer having a center line, a first metallized electrode layer applied to one side of the dielectric layer so that an unmetallized margin ex-tends along each edge of a pair of parallel edges of the di-electric layer, and a second metallized electrode layer applied to the other side of the dielectric layer so that an unmetallized area is located adjacent the second metallized electrode layer.
The dielectric layer is pleated once along the unmetallized areas off of the center line so that one edge of the margin containing edges extends beyond the other of the edges along the same end of the capacitor segment and metallized spray material in contact with the second electrode layer.
Description
3 1 ~
manuf~cture of conventional wound film capacitors. Furthermore, the capacitance per unit dielectric area is maximizec~ because of tlle substantially full use of the dielectric layer in the electric fielcl. Shorter winding lengths per unit capacitance are thereby required, reducing the winding labor. ~he dielectric lengths can also be calibrated and pre-cut to produce a capacitor of more accurate values. Another aàvantage of this type of capacitor is that there are no air layers between the metallized electrodes and the pleated film surfaces and this substantially increases the voltage, for example, one hundred volts or more, at which corona discharge starts, making this capacitor commercially attractive for new applications such as fluorescent lighting circuits~ Previously, fifty gauge film thickness or more was required of wound film capacitors to withstand the corona. With the capacitor of the present invention, thirty-two gauge or less dielectric film thickness may be utilized9 making ~und film capa-citors economically feasible for such applications.
~he McMahon patent suggested that leads could be attached to his capacitor by the well-known Schoop process. The application of high velocity metallic spray coatings tothe edges of the capacitor described by Mcl\~lahon is not commercially practical, however, because the spray will penetrate tllrough the dielectric area at a pleat and thereby short one electrode to the other. II the temperature and pressure of the spray are lowered, penet-ration of the dielectric tayers may be reduced but the adhesion of the metallic spray will generally be very poor. The multiple leads suggested in the McMahon patent also are not satisfactory since they tend to tear the dielectric ~_ a ~ ~ ., .L o ~ u material and to make the capacitor bully and inductive.
In order to solve the above mentioned spray shorting problem at a pleated edge, it has been suggested in Australian Patent No. 159, 958, patented on November 24, 1954 to provide unmetallized dielectric strips behind all of the pleats of a pleated metallized capacitor. While this solution may provide a technically feasible method of attaching leads to apleated metallized dielectric layer capacitorJ the number of unmetallized strips that are required on the dielectric layer greatly complicates the manu-~acturing process for both the dielectric layer itself and the pleated capacitor product. For example, in a capacitor having five pleats, there must be, in addition to the two unmetallized margin areas, five unmetallized strips that run along the entire length oi the dielectric material,with three of these strips being on one side of the dielectric layer and two of these strips being on the opposite side of the dielectric layer. It is ~ -apparent that the masking problems and the cost of manufacturing such a specialized item make the solution of the Australian patent commercially unattractive. This is especially true since the type of metallized dielectric layer that is u$ed in the capacitor of the present invention, (in which only the margin areas and one unmetallized central strip is required), is readily ~0 commercially available. Furthermore, the employment of an unmetallized strip behind the single pleated capacitor of the McMahon patent, however, still would not provide an end termination along the opposite edge of the wound capacitor segment that would allow a meSallized spray to be applied to this edge because the ends of the dielectric layer of the McMahon patent at this edge extended beyond both of the metallized electrodes and contact between the metallic spray and the inner electrode area would thereby be prevented .
~he leads of the capacitor of the United States Patent No. 3, 854, 075, i ssuecl Deceml)el 10, 1974 to John Philip Uhl, were used as mandrels to wind the pleated capacitor segment about the center, in a manner similar to that suggested in United States Patent No. 2, 887, 649 issued May 19, 1959 to Daniel B. Peck. In the Uhl patent, conductive foil tabs were inserted between the leads and the metallized electrode areas to make positive contact with the electrode and to protect the electrode from damage by the leads during winding. However, it has been determined that this construction leads to a higher failure rate than ~0 desirable due to opening of the electrode area around the periphery of the metal foil, for reasons which are not completely understood.
~he configuration of the capacitor of the present invention provides a product which has all of the advantages of single pleated, or single pleated and wound, capacitors and also has lhe added advantage that it may be manufactured with commercially available rnetallized dielectric material. A further advantage of the present invention is that the same basic starting material may be used to manufacture capacitors having à
number of different pleating combinations, which, of course, is not true for the capacitor of the Australian patent, in which each pleat combin-~0 ation requires a specially manufactured dielectric layer. In addition to the use of the present invention to manufacture wound film capacitors~
it is also possible to utilize the invention to produce ceramic capacitors in which the capacitor dielectric material is folded while the ceramic material is still in a "green" state, in a manner similar to that dis-~5 closed in United States Patent No. 3, 223, 494 issued December 14, 1965 to J. W. Crownover.
~.0~3.~
Thus broadly, the invention contemplates an elec~rical capa-citor segment whlch comprises a dielectric layer having a center line, a first metallized electrode layer applied to one side of the dielectric layer so that an unmetallized margin extends along each edge of a pair of parallel edges of the dielectric layer, and a second metallized electrode layer applied to the other side of the dielectric layer so that an unmetallized area is located ad-jacent the second metalli2ed electrode layer. The dielectric layer is pleated once along the unmetallized areas off of the center line 0 50 that one edge of the margin containing edges extends beyond the other of the edges along the same end of the capacitor segment and metallized spray material is in contact with the second electrode layer.
In a further embodiment the invention contemplates an electri-cal capacitor segment which comprises at least one group of pleated layers comprising a dielectric layer, a first metallized electrode layer applied to one side of the dielectric layer so that an un-metallized margin extends along each edge of a pair of parallel edges of the dielectric layer, a pair of metallized electrode 20 layers on the other side of the dielectric layer, and at least one unmetallized strip that runs between the metallized layers on the other side of the dielectric layer. The dielectric layer is pleated M number of times where M = a ~ (N)b where a is an odd num~er 3 or greater, and b is an even number 2 or greater, and where N may be zero or any positive integer so that at least one pleat of the pleated dielectric strip extends along one end of the pleated dielectric layer beyond at least one other pleat that extends along the same end as the extending pleat, or pleats, with all o~ the extending pleats having unmetallized strips behind them 30 along their length. The edges of the metallized dielectric strip which contain the margins extend along the opposite end of the pleated dielectric layer beyond the other plea~ts that extend along the same end as the margin containing edges, wherein the extending pleat or pleats along the one end of the dielectric layer and the margin containing edges along the other end of the dielectric layer are sufficient in length to allow metallized spray material to be sprayed against both of the ends without penetration of the spray far enough to contact any of the pleats except the extending pleat or pleats.
Case 316U-20 ~3~
Description of the l~)rawings ~he present invention is illustrated by reference to the drawings in which:
Fig. 1 is a perspective view of a portion of a metalli~ed dielectric layer which may be used in the construction of a capacitor in accordance with the present invention;
Fig. 2 is a perspective view of a partially pleated metallized di-electric layer in accordance with Fig. 1 having five pleat lines;
Fig. 3 is a perspective view of a fully pleated dielectric layer in accordance with Fig. 1;
l~ Fig. 4 is a perspective view of the fully pleated dielectric layer of Fig. 3 which, in addition, shows a winding mandrel and an unmetallized dielectric insert;
Fig. 5 is a diagrammatic showing of the winding of a capacitor segment in accordance with the construction of Fig. 4;
l~ Fig. 6 is an end view of a capacitor segment, before lead attacllment, that is wound in accordance with the showing of Figs.
4 and 5;
Fig. 7 is an end view of the wound capacitor segn~ent of Fig. 6 after it has been pressed into an oval shape;
Fig. ~3 is a side view of a completcd cap.lcilor follo~ g tlle attachment of axial leads;
., Case 31~8-20 ~3~
Fig. 9 is a side view of a completed capacitor following attach-ment of radial leads;
Fig. 10 is a perspective view of an alternate version of a capacitor constructed in accordance witll the present invention;
Fig. 11 is a perspective view of an additional alternate embodi-ment; ;
Fig. 12 is a perspective view of a further alternate embodiment;
Fig. 13 is a perspective view of a portion of a metallizecl dielectric layer which may be used in the construction of a capacitor in accordance with the present invention;
Fig. 14 is a perspective view of a single pleated dielectric layer in accordance with Fig. 13;
Fig. 15 is a perspective view of the fully pleated dielectric layer of Fig. 14 whichJ in addition, shows a winding mandrel and an unmetallized la dielectric insert;
Fig. 16 is a diagrammatic showing of the winding Oe a capacitor Segment in accordance witll the construction of Fig. 15;
Fig. 17 is a perspective view of a portion of a metallized dielectric layer which rnay be used in the construction of a capacitor in accor-~ dance with the present invention;
Fig. 18 is a perspective view of a pleated metalli%ed dielectriclayer in ~accordance with Fig. 17 having two pleat lines;
!
Case 316~ 20 ~0~3.~6 :Fig. 19 is a diagrammatic showing of the winding of a capacitor segment in accordance witl the construction of Fig. 18; and :Fig. 20 is a perspective view of an alternate version of a capacitor constructed in accordance with the present invelltiol~.
~echnical Description of the Invention A portion of a commercially available metallized dielectric strip which may be unwound from a reel, that is suitable for the maliing of a capacitor in accordance with the present invention is shown in Fig. 1.
~he metallized dielectric strip is formed with a dielcctric laycl 12 Or a thin film dielectric material, such as polyester, polypropylene, poly-styrene, polycarbonate or other suitable material. A thin metallized electrode layer 14 is applied to the upper surface of the dielectric layer 12 in such a fashion that unmetallized margin areas 16, 18 extend along the longitudinal edges of the strip 10. ~wo thill metallized electrode areas 20, 22 are applied to the lower surface of the dielectric layer 12 so that the metallized layer 20 extends to the left hand margin of the layer as shown in Fig. 1, while the metallized layer 22 e~tends to the right hand margin of the layer. ~ central unmetallized strip 24 lies between the metallized electrode areas 20, 22.
In the embodiment shown in Fig. 1, the longitudinal dimellsioll of the metallized strip 10 is shown along the arrows 26 while the narrow ` ` '" ~
(~ase 31(;8-20 transverse dimension is shown along the arrows 28. ~he capacitor is pleated along the imaginary line 30 which extends through tlle length of the unmetallized central strip 24. rrhis version of tlle presellt invention, however, is not limited to one in which folding is along longituclinal lines since a capacitor could be made in accordance with the present invention by pleating along transverse lines if the appropriate corresponding metallized and unmetallized areas were provided.
A partially pleated capacitor is shown in Fig. 2 wherein one pleat occurs along the longitudinal center line 30 and other pleats occur along the longitudinal pleat lines 32, 34, 36 and 38. It is to be noted that lines 32, 34, 36 and 38 are spaced so that the center pleat 40 ex-tends beyond the other pleats 42, 44 that run along the right hand long- -itudinal edge of the metallized strip 10 of Fig. 1 so that the inside of the pleat 40 in the area 46 is unmetallized. ~he e~;tension of the center pleat 40 beyond the pleats 42, 44 is preferably at least 0. 020 inches. In addition, it is noted that the pleats are positioned so that tlle lOngitudinal ends 4~, 50 of the metallized strip 10 are aligned with each other but so that they extend beyond the pleats 52, 54 that run along the left hand longitudinal edge of the metallized strip. Again, the ex-~ tension of the ends 48, 50 beyond the pleats 52, 54 is prefeI~al~ly at least 0. 020 inches. ~he unmetallized margin 16, therefore, faccs upwardly while the unmetallized margin 18 faces downwardLy when the capacitor Case 316~3-20 ~3~
segment has been fully pleated as shown in Fig. 3.
After the capacitor has beell processed to form the cap~citor seg-ment shown in Fig. 3, a number of different additional processing steps may be undertaken. l?or example, the pleated capacitor segrment of Fig. 3 could be used to form a capacitor merely by spraying the right and left hand longitudinal edges of the segment with a metallized spray, such as babbitt or other suitable metal, in accordance with conventional practice, and then electrical leads could be secured to them, for e~ample, by soldering. Alternately, the capacitor segment of F`ig. 3 could be cut along a transverse line, such as the line 43, and a number of such seg-ments could be stacked upon each other, with the terminal end 50 of one capacitor segment being adjacent to and aligned with the terminal end 48' of the capacltor segment that is positioned immediately belo~Y it, as shown diagrammatically by the dotted line representative of Fig. 3, and then their ends could be sprayed with a metallized spray and leads could then be secured to the stacked array of such segments. In conjunction with the p resently preferred embodiment of the present invention, however, Fig. 3 represents two layers of a capacitor segment formed by winding of the di-electric strip along the longitudinal dimension of the stri,v 1OJ aS shown in ~0 Figs. 4 and 5, to form a wound capacitor. Another version of this capacitorcould be achieved, however, by pleating the capacitor segment of l~ig. 3 a number of times transversely along transverse fold lines such as the line 43, or alternately pleating several times, and then completing the segInent by winding the remainder of the length of the dielectric strip.
Casc 31 G~3- 20 3~6~
~he winding of the capacitor segmellt of l~ig. 3 into a ~ound capacitor may be achieved with various winding techniques, including the use of a removable spllt mandrel such as the mandrel ~6 of Figs. 4 and 5.
~n unmetallized dielectric strip 5~ is desirably initially wound around the S mandrel to protect the metallized electrode areas of the metallized strip 10. Near the completion of winding, an additional unmetallized dielectric strip 60 is desirably wound into the structure to form an outer protective coating. ~he dielectric strip 60 may also be heat-sealed to itself to form the pleated capacitor segment 61 which is shown in Fig. 6. 'rhe removal of the mandrel 56 from the capacitor segment 61 leaves an opening 62 in the unit. ~he opening 62 may be closed by applying pressure, or pressure and heat~ in accordance with the type of dielectric use(l and conventional manufacturing techniques, to the capacitor segment ~1 so that it assumcs an oval shape as shown in Fig. 7.
Once the capacitor segment of the embodiment of Figs. 4 th~ough 7 has been wound, a metallized spray may then be directed against the longitudinal edges of the unit in accordance with conventional processing techniques to interconnect thc elcctl o(lc layers alollg thesc edges and to provide for the connection of electrical leads to the unit.
~0 ~he metallized spray will penetrate into the open area between the ends 48 and 50 on the left hand longitudinal edge of the capacitor segment, as shown diagrammatically in Fig. 3 to a depth such as that indicated , .,., - ,. ..
Case 31~ 20 3~,6 by the plane ~5. ~he plane 65 indicates the maximum depth that any high velocity spray particles will penetlate and it may tln~s bc located any place between the ends 48 and 50 of the metallized strip 10 and the edges oE the pleats 52, 54. ~ccordingly) the metallized spray material will extend into the left hand opening of the capacitor between the ends 4~, 50 far enough to nake contact to the two facing metallized electrode areas 20, 22, but not so far that it will penetrate through the dielectric material at the pleats 52, 54. ~he configuration of the present invention tllus provides for reliable lead termination at the left hand longitudinal edge of the capacitor segment of Fig. 3 without the necessity of providing unmetallized longitudinal strips along the inside of the pleats 52, 54, tl~ereby saving considerable processing expenses in the manufacture of completed capacitors OI this type.
~ermination to the right hand longitudinal edge of the capacitor ~5 segmellt of Fig. 3 is similarly provided by a metallized spray ~h ich ex-tends over the protruding center pleat 40 to a depth, such as that indicated by the plane 67, which is sufficient to allow the metallized spray to make good contact to the electrode area 14, but which will prevent the penetration of the spray metallic particles throu~h the dielect-O ric at the pleats 42, 44. ~he locationof the plane 67 may be anywhere between the edges of the pleats 42, 44 and the e(lge of the pleat 40 as long as there is sufficient depth of spray to provide adequate contact termination to the electrode area 14. Again, a considerable cost savings ~ ~ . ~ .
Case ~1 G ~3- 20 3~
is achieved by the prescnt invention since the pleats D~2, 4~, lil~e the pleats 52, 54, did not have to be provided with their own unmetallized strips. It will be noted in the present invention that only onc unmetallized strip 24 is required in the center of the metallized strip 109 and, thus, the same general pattern may be used for various pleat configurations and a separate individually configurated metalli~cd strip is no~ rcqui for each pleat pattern.
Once the metallic spray has been applied to the edges of the capacitor segment of l?ig. 7~ either radial or axial leads may be applied to it. For example, axial leads 70J 72 with conventional spiral "pig-tail"
ends (not shown) may be soldered, arc-welded or connected by other means to the sprayed edge termination layers 66, 68 at the ends o the wound ~ l;
film capacitor segment 61, as shown in Fig. 8. Alternately, raclial leads 74, 76 may be soldered, arc-welded or connected by other methods to 1~ the sprayed metàllized layers 66, 68 if a radial leaded capacitor is desired, as shown in Fig. 9.
It will be noted from the foregoing description that the number of pleats that may be used to form a capacitor in accorclance with the previously described embodiment of the present invention is M where ~0 M = 5 ~ (N)4 and N may be 0 or any positive integer. 'rhe number of pleats M in a capacitor made in accordance with this embodiment, therefore, will always be an odd number.
Other alternate versions of the present invention are shown in Case 31G~ 20 33~6 Figs. 10-12. In Fig. 10 the pleated capacitor segment is formed so that the end pleats ~2, 44 have unmetallized strips 46' behind these pleats while the center pleat 40 does not. ~he two end pleats 42, 44 extend be-yond the recessed center pleat 40. Ihis version is less desira~le, how-ever, than the version of Fig. 3 becausc it requires all a(ldiLiollal stri,u.
Another alternate embodiment is shown in Fig. 11 wherein only one of the end pleats 42 extends beyond the center pleat 40 and the other of the end pleats 44. In this version only one unmetallized strip 46" is required behind the extending end pleat 42, but the charging path is longer for this configuration than that of Fig. 3.
Still another alternate embodiment is ~lown in Fig. 12 which cliffers from the version shown in Fig. 3 in that intermediate dielectric layers ~9, 69' are inserted between alternating groups 71, 73 of pleated layers ~vith the center pleat extended, as in Fig. 3, but with the alternating groups 71, 73 facing in opposite directions. If the capacitor Oe Fig. 12 is to be a wound embodiment, the alternating groups 71, 73 o~ pleated layers which face in opposite directlons may be supplied fro}n a different pleated segment supply. Also, it is apparent that the groups of pleated layers shown in Figs. 10 and 11 could be employed to for}n a capacitor in accordance with tlle teaching of Fig. 12 by facing alternating groups of these layers in opposite directions ancl by scpar-ating these alternating groups with dielectric material.
t~ase ".16~3-20 3~L6~
~ portion of another commercially available metalli%ed dielectric strip which may be unwound from a reel, that is suitable for a making of a capacitor in accordance with the present invention is shown in Fig. 13.
~his metallized dielectric strip may also be forllled witll a dielcctric layer 112 of a thin film dielectric material, such as polyester, p oly,~ ropylellc, polystyrene, polycarbonate or other suitable material. ~ thin metallized electrode layer 114 is applied to the upper surface of the dielectric layer 112 in such a fashion that unmetallized margin areas 116, 118 extend along the longitudinal edges of the strip 110. 'rwo thin metallized electrode areas 12Q, 122 are applied to the lower surface of the dielectric layer 112 so that the metallized layer 120 e~tends to the left halld malgin of the layer as shown in Fig. 13, while the metallized layer 122 extencls to the right hand margin of the layer. A central unmetallized strip 124 lies between the metallized electrode areas 120, 122.
1~ In the embodiment shown in Fig. 13, the longitudinal dimension of the metallized strip 110 is shown along the arrows 126 tid~ile the narro~r transverse dimension is shown along the arro-vs 128. ~his is to allow the capacitor to be pleated along the imaginary line 130 which extends through the length of the unmetallized central strip 124. This version o~ the present invention, however, is also not limited to one in which folding is along longitudinal lines since a capacitor could be made in accordance with this version of the present invention by pleating along transverse lines if the appropriate corresponding llletallized and unmctalli%ed areas wcre provided.
C~lsc 31~ 20 3~i6 A capacitor with a single pleat 140 along line 130 is sllowll in Fig. 14 which is slightly off of the center linc 131 of the metalli%ccl strip 110 with the inside of the pleat 140 in the area being unmetallized. r~he longitudinal ends 148, 150 of the metallized strip 110 are arranged in a staggered pattern so that one end 48 extends beyond the other end 150 along the left hand longitudinal edge of the metallized strip because of the off-center pleat of the dielectric layer. ~he e~;tension of tlle encl l~S beyond thc end 150 is preferably at least 0. 020 inches, and this extension allows the metallic spray to make contact with at least the upwardly facing o electrode area 12~ shown i~ Fig. 14. The unmetallized margin 116 faces upwardly while the unmetallized margin 11~ faces downwardly when the capacitor segment has been pleated as shown in Fig. 14.
After the capacitor has been processed to form the capacitor seg-ment sllo~,vn in F`ig. 14, a number of different additional proc~ssing steps l~ may be undertaken. For example, the pleated capacitor segment of Fig. 14 could be used to form a capacitor merely by spraying the right and left hand longitudinal edges of the segment with a metallized spray. such as babbitt or other suitable metal, in accordallcc \vlth con-ventional practice, and then electrical leads could be securcd io them, `0 for example, by soldering. Alternately, the capacitor segment o-f Fig.
14 could be cut along a transverse line, such as the line 143, and a number of such segments could be stacked uyon each othel, with the termillal end 150 of one capacitor segment being adjacent to but not extending as far as the terminal end 148' of the capacitor scgmcllt that is p ositionecl `5 immediately below it, as shown diagrammatically by the dotted l;ne re-Ca,se 3168-20 ~3~l6~i presentative of Fig. 14, and then their ends could l?e sprayed with a met-allized spray and leads could then be secured to the staclced array of such segments. In conjunction with the presently preferred embodiment of the present inventio~, however, Fig. 14 re~rcsellts t~o laycls Or ~ c~ac;to segment formed by winding of the dielectric strip about tlle longitudinal dimension of the strip 110, as shown in Figs. 15 and 16, to form a wound capacitor. Another version of this capacitor could be achieved, however, by pleating the capacitor segment of Fig. 14 a number of times transversely along transverse fold lines, such as the line 143, or alternately, pleating several times and then completing the segment by wincling the remainclcr ol the length of the dielectric str-ip.
~he winding of the capacitor segment of Fig. 14 into a wound capacitor may be achieved with various winding techniques, including the use o a split mandrel such as the mandrel 156 of Figs. 15 and 16, which may be removed from the capacitor segment after it has been wound.
~n unmetallized dielectric strip 58 is desirably initially wound around the mandrel to protect the metallized electrode areas of the metallized strip 110. ~he winding of the capacitor segment then continues until it is almost completed, at which time an additional unmetallized clielectric ~ strip 160 is then desirably wound into the structure to form an outer pro-tective coating. ~he dielectric strip 160 may also l~e heat-sealed to itself to form a pleated capacitor segment in the manner shown in Fig. 5 'rhe Case 31~8-20 removal of the mandrel 156 Erom the wound capacitor segment leaves an open-ing in the unit. ~his opening may be closed by applying pressure, or pressure and heat in accordance with the type of dielectric layer used and conventional manufacturing techniques to the capacitor segnlcllt so that it assumes an oval shape as shown in Fig. 6.
Once the capacitor segment has been wound, a metallized spray may then be directed against the longitudinal edges of the unit in accordance with conventional processing techniques to interconnect the electrode layers along these edges and to provide for the connection oE electrical leads to the unit. ~he metallized spray will penetrate into the open area resulting from the staggering of the ends 148 and 150 on the left hand longitudinal edge of the capacitor segment, so that the inner electrode provided by the metallized areas 120, 122, is contacted by the sprayed metal particles, but so that the electrode layer 114 is not contacted by such particlesJ as indicated by the imaginar~y plallc lG5 whicll represents the maximum depth of penetration of the spray particles. 'rhe configuration of the present invention thus provides for reliable lead termination at the left hand longitudinal edge oE the capacitor segment of Fig. 14 in a manner such that metalli~ed end terminations may be employed ~rith a single pleat metallized capa-citor. ~ermination to the right hand longitudinal edge Or the capacito segment of Fig. 15 is similarly provided by a metalliæed spray which extends over the protruding center pleat 140 to a depth which .
Case 31G8-20 is sufficient to allow the metallized spray to make good contact to the electrode area 114.
Once the metallic spray has been applied to the edgcs of thc capacitor segment either radial or axial leads may be applied to it as previously shown in Figs. 7 and 8, A portion of another commercially available metallized dielectric strip which may be unwound from a reel, that is suitable for a making of a capacitor in accordance with the present inventioll is shown in Fig. 17. ~his metallized dielectric strip may also be formed with a dielectric layer 212 of a thin film dielectric material, such as polyester, polypropylene, polystyrene, polycarbonate or other suitable material. A
thin metallized electrode layer 214 is applied to the upper surface of the dielectric layer 212 and a thin metallized electrode layer 220 is applied to the lower surface of the dielectric laycr in S-lCh a fasllioll ~5 that unmetallized margin areas 216, 218 extend along the opposite long-itudinal edges of the strip 210 on opposite sides of the strip.
`in the embodiment shown in Fig. 17J the longitudinal dimension of the metallized strip 210 is shown along the arrows 226 while the narrow transverse dimension is shown aiong the arrows 2')8. ~he ~ capacitor is pleated along two imaginary lines 230, 232 whicll extend through the length of the strip 210. ~his version of the present il-ventionJ
howeverJ is also not limited to one in which folding is along two longitudinal casc 3lGn-~o 3~;6 lines since a capacitor could be made in accordance with tl~is ~ ersioll of the present invention by pleating along any even number of transverse lines.
A pleated capacitor is shown in Fig~ 18 wherein one pleat occurs along the longitudinal line 230 and another pleat occurs along the long-itudinal lines 232. It is to be noted that pleat lines 230, 2~2 are spaced so that the margin area 218 extends beyond the pleat 2~2 that runs ~long thc right hand longitudinal edge of the metallized slrip 210 of Fig. 17 witll thc margin area 218 facing downwardly. ~he extension oE the margin area 218 beyond the pleats 242 is preferably at least 0. 020 inches. In addition, it is noted that the margin area 216 is positioned so that it extends beyond the pleat 252 that runs along the left hand longitudinal edge of the met-allized strip and faces upwardly. Again, the cxtellsioll oî thc margi area 216 beyond the pleat 252 is preferably at least 0. 020 inches.
~fter the capacitor has been processed to form the capacitor seg-ment shown in Fig. 18, a number of different additional processing steps may be undertaken. For example, the pleated capacitor segrnent of Fig. 18 could be used to form a capacitor merely by sprayillg~ thc righ~
and left hand longitudinal edges of the segment with a metallix,ed spray, such as babbitt or other suitable metal, in accordance with conventional practice, and then electrical leads could be secured to them, for ex-ample. by soldering. ~lternately, the capacitor .segment of Fig. 18 could be cut along a transverse line, such as the line 243~ and a number Case :316 8-~0 ~ 3~
of such segments could be stacked upon eacll other, witll thc CIO~Vll-wardly facing margin 218 of one capacitor segment being adjacent to and aligned with a corresponding upwardly facing margin 218' of the capacitor segment that is positioned immediately below it, as sho~vn diagrammatically by the dotted line representative of Fig. 18, and then their ends could be sprayed with a metallized spray and leads could then be secured to the stacl;ed array of such segments. In conjunction with the presently preferred embodiment OI the present invention, how-ever, Fig. 19 represents two layers of a capacitor segment formed by '~ winding of the dielectric strip about the center of the longitudinal dimen-sion of the strip 210, as shown in Fig. 19, So form a wound capacitor seg-ment. Another version of this capacitor coi~ be achieved, ho\v~ver, by pleating~ instead ol winding, the capacitor segment of Fig. 18 a number of times along transverse fold lines such as the line 243. ~1ternate1y, the capacitor segment could be pleated transversely two or more times ~bout transverse lines~ such as the line 243, and then the segment could be comp1eted by windin~ the remainder of the length of the ` dielectric strip.
~he winding of the capacitor segment of Fig. 18 into a ~ und 1~ capacitor may be achieved with various winding techniques, including the use of a split mandrel such as the mandrel 256 of Fig. 19, which is removed from the capacitor segment after it has been wound. An unmet-allized dielectric strip (not shown) may be wound around the str~lcture to f~ :
Case 316~-20 ~0~3~
form an outer protective coating. ~his dielectric strip may be heat-sealed to itself to form the pleated capacitor segment, as shown in Fig. 6. ~he removal of the mandrel 56 from the capacitor segment leaves an opening in the unit. ~he opening may again be closed by applying pressure, or pressure and heat, in accordance with thc type of dielectric layer used and conventional manufacturing techniques to the capacitor segment so that it assumes an oval shape, as shown in l~ig. 7.
Once the capacitor segment has been wound, a metallized spray may then be directed against the longitudinal edges of tlle unit il~
accordance with conventional processing techniques to interconnect the electrode layers along these edges and to provide for the connection of electrical leads to the unit. The r~letallized spray will penetrate into the open area between the margin 216 areas Oll the left hand longitudinal edge of the capacitor segment, as shown diagrammatically in Fig. 18 to a depth such as that indicated by the plane 26G, so as to make contact with the electrode area 220. ~he plane 26G indicates the maximum depth that any high velocity spray particles will penetrate and it may thus be located any place between the end oE the margin 216 2Q areas of the metallized strip 210 and the edge of the pleat 252.
Accordingly, the metallized spray material will exlell(l into tlle left hand opening of the capacitor between the margill 216 areas far enougll to make contact to the facing metallized electrode on the other side of the dielectric strip, but not so far that it will penetrate through the ~5 dielectric material at the pieat 252.
- 22 ~
Case ~1G8-20 1.~ i6 ~erlllination to the right halld longitudinal eclge of the capacitor segment of Fig. 18 is similarly provided ~y a metallized spray which extends over the margin 218 area to a depth, such as that indicated by the plane 268, which is sufficient to allow the metallized spray to make good contact to the electrode 214 on the inside of the margin 218 area but ~VhiCIl ~vill prevent the penetration of the spray metallic par-ticles through the dielectric at the pleat 242. ~he location o~ thc plane
manuf~cture of conventional wound film capacitors. Furthermore, the capacitance per unit dielectric area is maximizec~ because of tlle substantially full use of the dielectric layer in the electric fielcl. Shorter winding lengths per unit capacitance are thereby required, reducing the winding labor. ~he dielectric lengths can also be calibrated and pre-cut to produce a capacitor of more accurate values. Another aàvantage of this type of capacitor is that there are no air layers between the metallized electrodes and the pleated film surfaces and this substantially increases the voltage, for example, one hundred volts or more, at which corona discharge starts, making this capacitor commercially attractive for new applications such as fluorescent lighting circuits~ Previously, fifty gauge film thickness or more was required of wound film capacitors to withstand the corona. With the capacitor of the present invention, thirty-two gauge or less dielectric film thickness may be utilized9 making ~und film capa-citors economically feasible for such applications.
~he McMahon patent suggested that leads could be attached to his capacitor by the well-known Schoop process. The application of high velocity metallic spray coatings tothe edges of the capacitor described by Mcl\~lahon is not commercially practical, however, because the spray will penetrate tllrough the dielectric area at a pleat and thereby short one electrode to the other. II the temperature and pressure of the spray are lowered, penet-ration of the dielectric tayers may be reduced but the adhesion of the metallic spray will generally be very poor. The multiple leads suggested in the McMahon patent also are not satisfactory since they tend to tear the dielectric ~_ a ~ ~ ., .L o ~ u material and to make the capacitor bully and inductive.
In order to solve the above mentioned spray shorting problem at a pleated edge, it has been suggested in Australian Patent No. 159, 958, patented on November 24, 1954 to provide unmetallized dielectric strips behind all of the pleats of a pleated metallized capacitor. While this solution may provide a technically feasible method of attaching leads to apleated metallized dielectric layer capacitorJ the number of unmetallized strips that are required on the dielectric layer greatly complicates the manu-~acturing process for both the dielectric layer itself and the pleated capacitor product. For example, in a capacitor having five pleats, there must be, in addition to the two unmetallized margin areas, five unmetallized strips that run along the entire length oi the dielectric material,with three of these strips being on one side of the dielectric layer and two of these strips being on the opposite side of the dielectric layer. It is ~ -apparent that the masking problems and the cost of manufacturing such a specialized item make the solution of the Australian patent commercially unattractive. This is especially true since the type of metallized dielectric layer that is u$ed in the capacitor of the present invention, (in which only the margin areas and one unmetallized central strip is required), is readily ~0 commercially available. Furthermore, the employment of an unmetallized strip behind the single pleated capacitor of the McMahon patent, however, still would not provide an end termination along the opposite edge of the wound capacitor segment that would allow a meSallized spray to be applied to this edge because the ends of the dielectric layer of the McMahon patent at this edge extended beyond both of the metallized electrodes and contact between the metallic spray and the inner electrode area would thereby be prevented .
~he leads of the capacitor of the United States Patent No. 3, 854, 075, i ssuecl Deceml)el 10, 1974 to John Philip Uhl, were used as mandrels to wind the pleated capacitor segment about the center, in a manner similar to that suggested in United States Patent No. 2, 887, 649 issued May 19, 1959 to Daniel B. Peck. In the Uhl patent, conductive foil tabs were inserted between the leads and the metallized electrode areas to make positive contact with the electrode and to protect the electrode from damage by the leads during winding. However, it has been determined that this construction leads to a higher failure rate than ~0 desirable due to opening of the electrode area around the periphery of the metal foil, for reasons which are not completely understood.
~he configuration of the capacitor of the present invention provides a product which has all of the advantages of single pleated, or single pleated and wound, capacitors and also has lhe added advantage that it may be manufactured with commercially available rnetallized dielectric material. A further advantage of the present invention is that the same basic starting material may be used to manufacture capacitors having à
number of different pleating combinations, which, of course, is not true for the capacitor of the Australian patent, in which each pleat combin-~0 ation requires a specially manufactured dielectric layer. In addition to the use of the present invention to manufacture wound film capacitors~
it is also possible to utilize the invention to produce ceramic capacitors in which the capacitor dielectric material is folded while the ceramic material is still in a "green" state, in a manner similar to that dis-~5 closed in United States Patent No. 3, 223, 494 issued December 14, 1965 to J. W. Crownover.
~.0~3.~
Thus broadly, the invention contemplates an elec~rical capa-citor segment whlch comprises a dielectric layer having a center line, a first metallized electrode layer applied to one side of the dielectric layer so that an unmetallized margin extends along each edge of a pair of parallel edges of the dielectric layer, and a second metallized electrode layer applied to the other side of the dielectric layer so that an unmetallized area is located ad-jacent the second metalli2ed electrode layer. The dielectric layer is pleated once along the unmetallized areas off of the center line 0 50 that one edge of the margin containing edges extends beyond the other of the edges along the same end of the capacitor segment and metallized spray material is in contact with the second electrode layer.
In a further embodiment the invention contemplates an electri-cal capacitor segment which comprises at least one group of pleated layers comprising a dielectric layer, a first metallized electrode layer applied to one side of the dielectric layer so that an un-metallized margin extends along each edge of a pair of parallel edges of the dielectric layer, a pair of metallized electrode 20 layers on the other side of the dielectric layer, and at least one unmetallized strip that runs between the metallized layers on the other side of the dielectric layer. The dielectric layer is pleated M number of times where M = a ~ (N)b where a is an odd num~er 3 or greater, and b is an even number 2 or greater, and where N may be zero or any positive integer so that at least one pleat of the pleated dielectric strip extends along one end of the pleated dielectric layer beyond at least one other pleat that extends along the same end as the extending pleat, or pleats, with all o~ the extending pleats having unmetallized strips behind them 30 along their length. The edges of the metallized dielectric strip which contain the margins extend along the opposite end of the pleated dielectric layer beyond the other plea~ts that extend along the same end as the margin containing edges, wherein the extending pleat or pleats along the one end of the dielectric layer and the margin containing edges along the other end of the dielectric layer are sufficient in length to allow metallized spray material to be sprayed against both of the ends without penetration of the spray far enough to contact any of the pleats except the extending pleat or pleats.
Case 316U-20 ~3~
Description of the l~)rawings ~he present invention is illustrated by reference to the drawings in which:
Fig. 1 is a perspective view of a portion of a metalli~ed dielectric layer which may be used in the construction of a capacitor in accordance with the present invention;
Fig. 2 is a perspective view of a partially pleated metallized di-electric layer in accordance with Fig. 1 having five pleat lines;
Fig. 3 is a perspective view of a fully pleated dielectric layer in accordance with Fig. 1;
l~ Fig. 4 is a perspective view of the fully pleated dielectric layer of Fig. 3 which, in addition, shows a winding mandrel and an unmetallized dielectric insert;
Fig. 5 is a diagrammatic showing of the winding of a capacitor segment in accordance with the construction of Fig. 4;
l~ Fig. 6 is an end view of a capacitor segment, before lead attacllment, that is wound in accordance with the showing of Figs.
4 and 5;
Fig. 7 is an end view of the wound capacitor segn~ent of Fig. 6 after it has been pressed into an oval shape;
Fig. ~3 is a side view of a completcd cap.lcilor follo~ g tlle attachment of axial leads;
., Case 31~8-20 ~3~
Fig. 9 is a side view of a completed capacitor following attach-ment of radial leads;
Fig. 10 is a perspective view of an alternate version of a capacitor constructed in accordance witll the present invention;
Fig. 11 is a perspective view of an additional alternate embodi-ment; ;
Fig. 12 is a perspective view of a further alternate embodiment;
Fig. 13 is a perspective view of a portion of a metallizecl dielectric layer which may be used in the construction of a capacitor in accordance with the present invention;
Fig. 14 is a perspective view of a single pleated dielectric layer in accordance with Fig. 13;
Fig. 15 is a perspective view of the fully pleated dielectric layer of Fig. 14 whichJ in addition, shows a winding mandrel and an unmetallized la dielectric insert;
Fig. 16 is a diagrammatic showing of the winding Oe a capacitor Segment in accordance witll the construction of Fig. 15;
Fig. 17 is a perspective view of a portion of a metallized dielectric layer which rnay be used in the construction of a capacitor in accor-~ dance with the present invention;
Fig. 18 is a perspective view of a pleated metalli%ed dielectriclayer in ~accordance with Fig. 17 having two pleat lines;
!
Case 316~ 20 ~0~3.~6 :Fig. 19 is a diagrammatic showing of the winding of a capacitor segment in accordance witl the construction of Fig. 18; and :Fig. 20 is a perspective view of an alternate version of a capacitor constructed in accordance with the present invelltiol~.
~echnical Description of the Invention A portion of a commercially available metallized dielectric strip which may be unwound from a reel, that is suitable for the maliing of a capacitor in accordance with the present invention is shown in Fig. 1.
~he metallized dielectric strip is formed with a dielcctric laycl 12 Or a thin film dielectric material, such as polyester, polypropylene, poly-styrene, polycarbonate or other suitable material. A thin metallized electrode layer 14 is applied to the upper surface of the dielectric layer 12 in such a fashion that unmetallized margin areas 16, 18 extend along the longitudinal edges of the strip 10. ~wo thill metallized electrode areas 20, 22 are applied to the lower surface of the dielectric layer 12 so that the metallized layer 20 extends to the left hand margin of the layer as shown in Fig. 1, while the metallized layer 22 e~tends to the right hand margin of the layer. ~ central unmetallized strip 24 lies between the metallized electrode areas 20, 22.
In the embodiment shown in Fig. 1, the longitudinal dimellsioll of the metallized strip 10 is shown along the arrows 26 while the narrow ` ` '" ~
(~ase 31(;8-20 transverse dimension is shown along the arrows 28. ~he capacitor is pleated along the imaginary line 30 which extends through tlle length of the unmetallized central strip 24. rrhis version of tlle presellt invention, however, is not limited to one in which folding is along longituclinal lines since a capacitor could be made in accordance with the present invention by pleating along transverse lines if the appropriate corresponding metallized and unmetallized areas were provided.
A partially pleated capacitor is shown in Fig. 2 wherein one pleat occurs along the longitudinal center line 30 and other pleats occur along the longitudinal pleat lines 32, 34, 36 and 38. It is to be noted that lines 32, 34, 36 and 38 are spaced so that the center pleat 40 ex-tends beyond the other pleats 42, 44 that run along the right hand long- -itudinal edge of the metallized strip 10 of Fig. 1 so that the inside of the pleat 40 in the area 46 is unmetallized. ~he e~;tension of the center pleat 40 beyond the pleats 42, 44 is preferably at least 0. 020 inches. In addition, it is noted that the pleats are positioned so that tlle lOngitudinal ends 4~, 50 of the metallized strip 10 are aligned with each other but so that they extend beyond the pleats 52, 54 that run along the left hand longitudinal edge of the metallized strip. Again, the ex-~ tension of the ends 48, 50 beyond the pleats 52, 54 is prefeI~al~ly at least 0. 020 inches. ~he unmetallized margin 16, therefore, faccs upwardly while the unmetallized margin 18 faces downwardLy when the capacitor Case 316~3-20 ~3~
segment has been fully pleated as shown in Fig. 3.
After the capacitor has beell processed to form the cap~citor seg-ment shown in Fig. 3, a number of different additional processing steps may be undertaken. l?or example, the pleated capacitor segrment of Fig. 3 could be used to form a capacitor merely by spraying the right and left hand longitudinal edges of the segment with a metallized spray, such as babbitt or other suitable metal, in accordance with conventional practice, and then electrical leads could be secured to them, for e~ample, by soldering. Alternately, the capacitor segment of F`ig. 3 could be cut along a transverse line, such as the line 43, and a number of such seg-ments could be stacked upon each other, with the terminal end 50 of one capacitor segment being adjacent to and aligned with the terminal end 48' of the capacltor segment that is positioned immediately belo~Y it, as shown diagrammatically by the dotted line representative of Fig. 3, and then their ends could be sprayed with a metallized spray and leads could then be secured to the stacked array of such segments. In conjunction with the p resently preferred embodiment of the present invention, however, Fig. 3 represents two layers of a capacitor segment formed by winding of the di-electric strip along the longitudinal dimension of the stri,v 1OJ aS shown in ~0 Figs. 4 and 5, to form a wound capacitor. Another version of this capacitorcould be achieved, however, by pleating the capacitor segment of l~ig. 3 a number of times transversely along transverse fold lines such as the line 43, or alternately pleating several times, and then completing the segInent by winding the remainder of the length of the dielectric strip.
Casc 31 G~3- 20 3~6~
~he winding of the capacitor segmellt of l~ig. 3 into a ~ound capacitor may be achieved with various winding techniques, including the use of a removable spllt mandrel such as the mandrel ~6 of Figs. 4 and 5.
~n unmetallized dielectric strip 5~ is desirably initially wound around the S mandrel to protect the metallized electrode areas of the metallized strip 10. Near the completion of winding, an additional unmetallized dielectric strip 60 is desirably wound into the structure to form an outer protective coating. ~he dielectric strip 60 may also be heat-sealed to itself to form the pleated capacitor segment 61 which is shown in Fig. 6. 'rhe removal of the mandrel 56 from the capacitor segment 61 leaves an opening 62 in the unit. ~he opening 62 may be closed by applying pressure, or pressure and heat~ in accordance with the type of dielectric use(l and conventional manufacturing techniques, to the capacitor segment ~1 so that it assumcs an oval shape as shown in Fig. 7.
Once the capacitor segment of the embodiment of Figs. 4 th~ough 7 has been wound, a metallized spray may then be directed against the longitudinal edges of the unit in accordance with conventional processing techniques to interconnect thc elcctl o(lc layers alollg thesc edges and to provide for the connection of electrical leads to the unit.
~0 ~he metallized spray will penetrate into the open area between the ends 48 and 50 on the left hand longitudinal edge of the capacitor segment, as shown diagrammatically in Fig. 3 to a depth such as that indicated , .,., - ,. ..
Case 31~ 20 3~,6 by the plane ~5. ~he plane 65 indicates the maximum depth that any high velocity spray particles will penetlate and it may tln~s bc located any place between the ends 48 and 50 of the metallized strip 10 and the edges oE the pleats 52, 54. ~ccordingly) the metallized spray material will extend into the left hand opening of the capacitor between the ends 4~, 50 far enough to nake contact to the two facing metallized electrode areas 20, 22, but not so far that it will penetrate through the dielectric material at the pleats 52, 54. ~he configuration of the present invention tllus provides for reliable lead termination at the left hand longitudinal edge of the capacitor segment of Fig. 3 without the necessity of providing unmetallized longitudinal strips along the inside of the pleats 52, 54, tl~ereby saving considerable processing expenses in the manufacture of completed capacitors OI this type.
~ermination to the right hand longitudinal edge of the capacitor ~5 segmellt of Fig. 3 is similarly provided by a metallized spray ~h ich ex-tends over the protruding center pleat 40 to a depth, such as that indicated by the plane 67, which is sufficient to allow the metallized spray to make good contact to the electrode area 14, but which will prevent the penetration of the spray metallic particles throu~h the dielect-O ric at the pleats 42, 44. ~he locationof the plane 67 may be anywhere between the edges of the pleats 42, 44 and the e(lge of the pleat 40 as long as there is sufficient depth of spray to provide adequate contact termination to the electrode area 14. Again, a considerable cost savings ~ ~ . ~ .
Case ~1 G ~3- 20 3~
is achieved by the prescnt invention since the pleats D~2, 4~, lil~e the pleats 52, 54, did not have to be provided with their own unmetallized strips. It will be noted in the present invention that only onc unmetallized strip 24 is required in the center of the metallized strip 109 and, thus, the same general pattern may be used for various pleat configurations and a separate individually configurated metalli~cd strip is no~ rcqui for each pleat pattern.
Once the metallic spray has been applied to the edges of the capacitor segment of l?ig. 7~ either radial or axial leads may be applied to it. For example, axial leads 70J 72 with conventional spiral "pig-tail"
ends (not shown) may be soldered, arc-welded or connected by other means to the sprayed edge termination layers 66, 68 at the ends o the wound ~ l;
film capacitor segment 61, as shown in Fig. 8. Alternately, raclial leads 74, 76 may be soldered, arc-welded or connected by other methods to 1~ the sprayed metàllized layers 66, 68 if a radial leaded capacitor is desired, as shown in Fig. 9.
It will be noted from the foregoing description that the number of pleats that may be used to form a capacitor in accorclance with the previously described embodiment of the present invention is M where ~0 M = 5 ~ (N)4 and N may be 0 or any positive integer. 'rhe number of pleats M in a capacitor made in accordance with this embodiment, therefore, will always be an odd number.
Other alternate versions of the present invention are shown in Case 31G~ 20 33~6 Figs. 10-12. In Fig. 10 the pleated capacitor segment is formed so that the end pleats ~2, 44 have unmetallized strips 46' behind these pleats while the center pleat 40 does not. ~he two end pleats 42, 44 extend be-yond the recessed center pleat 40. Ihis version is less desira~le, how-ever, than the version of Fig. 3 becausc it requires all a(ldiLiollal stri,u.
Another alternate embodiment is shown in Fig. 11 wherein only one of the end pleats 42 extends beyond the center pleat 40 and the other of the end pleats 44. In this version only one unmetallized strip 46" is required behind the extending end pleat 42, but the charging path is longer for this configuration than that of Fig. 3.
Still another alternate embodiment is ~lown in Fig. 12 which cliffers from the version shown in Fig. 3 in that intermediate dielectric layers ~9, 69' are inserted between alternating groups 71, 73 of pleated layers ~vith the center pleat extended, as in Fig. 3, but with the alternating groups 71, 73 facing in opposite directions. If the capacitor Oe Fig. 12 is to be a wound embodiment, the alternating groups 71, 73 o~ pleated layers which face in opposite directlons may be supplied fro}n a different pleated segment supply. Also, it is apparent that the groups of pleated layers shown in Figs. 10 and 11 could be employed to for}n a capacitor in accordance with tlle teaching of Fig. 12 by facing alternating groups of these layers in opposite directions ancl by scpar-ating these alternating groups with dielectric material.
t~ase ".16~3-20 3~L6~
~ portion of another commercially available metalli%ed dielectric strip which may be unwound from a reel, that is suitable for a making of a capacitor in accordance with the present invention is shown in Fig. 13.
~his metallized dielectric strip may also be forllled witll a dielcctric layer 112 of a thin film dielectric material, such as polyester, p oly,~ ropylellc, polystyrene, polycarbonate or other suitable material. ~ thin metallized electrode layer 114 is applied to the upper surface of the dielectric layer 112 in such a fashion that unmetallized margin areas 116, 118 extend along the longitudinal edges of the strip 110. 'rwo thin metallized electrode areas 12Q, 122 are applied to the lower surface of the dielectric layer 112 so that the metallized layer 120 e~tends to the left halld malgin of the layer as shown in Fig. 13, while the metallized layer 122 extencls to the right hand margin of the layer. A central unmetallized strip 124 lies between the metallized electrode areas 120, 122.
1~ In the embodiment shown in Fig. 13, the longitudinal dimension of the metallized strip 110 is shown along the arrows 126 tid~ile the narro~r transverse dimension is shown along the arro-vs 128. ~his is to allow the capacitor to be pleated along the imaginary line 130 which extends through the length of the unmetallized central strip 124. This version o~ the present invention, however, is also not limited to one in which folding is along longitudinal lines since a capacitor could be made in accordance with this version of the present invention by pleating along transverse lines if the appropriate corresponding llletallized and unmctalli%ed areas wcre provided.
C~lsc 31~ 20 3~i6 A capacitor with a single pleat 140 along line 130 is sllowll in Fig. 14 which is slightly off of the center linc 131 of the metalli%ccl strip 110 with the inside of the pleat 140 in the area being unmetallized. r~he longitudinal ends 148, 150 of the metallized strip 110 are arranged in a staggered pattern so that one end 48 extends beyond the other end 150 along the left hand longitudinal edge of the metallized strip because of the off-center pleat of the dielectric layer. ~he e~;tension of tlle encl l~S beyond thc end 150 is preferably at least 0. 020 inches, and this extension allows the metallic spray to make contact with at least the upwardly facing o electrode area 12~ shown i~ Fig. 14. The unmetallized margin 116 faces upwardly while the unmetallized margin 11~ faces downwardly when the capacitor segment has been pleated as shown in Fig. 14.
After the capacitor has been processed to form the capacitor seg-ment sllo~,vn in F`ig. 14, a number of different additional proc~ssing steps l~ may be undertaken. For example, the pleated capacitor segment of Fig. 14 could be used to form a capacitor merely by spraying the right and left hand longitudinal edges of the segment with a metallized spray. such as babbitt or other suitable metal, in accordallcc \vlth con-ventional practice, and then electrical leads could be securcd io them, `0 for example, by soldering. Alternately, the capacitor segment o-f Fig.
14 could be cut along a transverse line, such as the line 143, and a number of such segments could be stacked uyon each othel, with the termillal end 150 of one capacitor segment being adjacent to but not extending as far as the terminal end 148' of the capacitor scgmcllt that is p ositionecl `5 immediately below it, as shown diagrammatically by the dotted l;ne re-Ca,se 3168-20 ~3~l6~i presentative of Fig. 14, and then their ends could l?e sprayed with a met-allized spray and leads could then be secured to the staclced array of such segments. In conjunction with the presently preferred embodiment of the present inventio~, however, Fig. 14 re~rcsellts t~o laycls Or ~ c~ac;to segment formed by winding of the dielectric strip about tlle longitudinal dimension of the strip 110, as shown in Figs. 15 and 16, to form a wound capacitor. Another version of this capacitor could be achieved, however, by pleating the capacitor segment of Fig. 14 a number of times transversely along transverse fold lines, such as the line 143, or alternately, pleating several times and then completing the segment by wincling the remainclcr ol the length of the dielectric str-ip.
~he winding of the capacitor segment of Fig. 14 into a wound capacitor may be achieved with various winding techniques, including the use o a split mandrel such as the mandrel 156 of Figs. 15 and 16, which may be removed from the capacitor segment after it has been wound.
~n unmetallized dielectric strip 58 is desirably initially wound around the mandrel to protect the metallized electrode areas of the metallized strip 110. ~he winding of the capacitor segment then continues until it is almost completed, at which time an additional unmetallized clielectric ~ strip 160 is then desirably wound into the structure to form an outer pro-tective coating. ~he dielectric strip 160 may also l~e heat-sealed to itself to form a pleated capacitor segment in the manner shown in Fig. 5 'rhe Case 31~8-20 removal of the mandrel 156 Erom the wound capacitor segment leaves an open-ing in the unit. ~his opening may be closed by applying pressure, or pressure and heat in accordance with the type of dielectric layer used and conventional manufacturing techniques to the capacitor segnlcllt so that it assumes an oval shape as shown in Fig. 6.
Once the capacitor segment has been wound, a metallized spray may then be directed against the longitudinal edges of the unit in accordance with conventional processing techniques to interconnect the electrode layers along these edges and to provide for the connection oE electrical leads to the unit. ~he metallized spray will penetrate into the open area resulting from the staggering of the ends 148 and 150 on the left hand longitudinal edge of the capacitor segment, so that the inner electrode provided by the metallized areas 120, 122, is contacted by the sprayed metal particles, but so that the electrode layer 114 is not contacted by such particlesJ as indicated by the imaginar~y plallc lG5 whicll represents the maximum depth of penetration of the spray particles. 'rhe configuration of the present invention thus provides for reliable lead termination at the left hand longitudinal edge oE the capacitor segment of Fig. 14 in a manner such that metalli~ed end terminations may be employed ~rith a single pleat metallized capa-citor. ~ermination to the right hand longitudinal edge Or the capacito segment of Fig. 15 is similarly provided by a metalliæed spray which extends over the protruding center pleat 140 to a depth which .
Case 31G8-20 is sufficient to allow the metallized spray to make good contact to the electrode area 114.
Once the metallic spray has been applied to the edgcs of thc capacitor segment either radial or axial leads may be applied to it as previously shown in Figs. 7 and 8, A portion of another commercially available metallized dielectric strip which may be unwound from a reel, that is suitable for a making of a capacitor in accordance with the present inventioll is shown in Fig. 17. ~his metallized dielectric strip may also be formed with a dielectric layer 212 of a thin film dielectric material, such as polyester, polypropylene, polystyrene, polycarbonate or other suitable material. A
thin metallized electrode layer 214 is applied to the upper surface of the dielectric layer 212 and a thin metallized electrode layer 220 is applied to the lower surface of the dielectric laycr in S-lCh a fasllioll ~5 that unmetallized margin areas 216, 218 extend along the opposite long-itudinal edges of the strip 210 on opposite sides of the strip.
`in the embodiment shown in Fig. 17J the longitudinal dimension of the metallized strip 210 is shown along the arrows 226 while the narrow transverse dimension is shown aiong the arrows 2')8. ~he ~ capacitor is pleated along two imaginary lines 230, 232 whicll extend through the length of the strip 210. ~his version of the present il-ventionJ
howeverJ is also not limited to one in which folding is along two longitudinal casc 3lGn-~o 3~;6 lines since a capacitor could be made in accordance with tl~is ~ ersioll of the present invention by pleating along any even number of transverse lines.
A pleated capacitor is shown in Fig~ 18 wherein one pleat occurs along the longitudinal line 230 and another pleat occurs along the long-itudinal lines 232. It is to be noted that pleat lines 230, 2~2 are spaced so that the margin area 218 extends beyond the pleat 2~2 that runs ~long thc right hand longitudinal edge of the metallized slrip 210 of Fig. 17 witll thc margin area 218 facing downwardly. ~he extension oE the margin area 218 beyond the pleats 242 is preferably at least 0. 020 inches. In addition, it is noted that the margin area 216 is positioned so that it extends beyond the pleat 252 that runs along the left hand longitudinal edge of the met-allized strip and faces upwardly. Again, the cxtellsioll oî thc margi area 216 beyond the pleat 252 is preferably at least 0. 020 inches.
~fter the capacitor has been processed to form the capacitor seg-ment shown in Fig. 18, a number of different additional processing steps may be undertaken. For example, the pleated capacitor segrnent of Fig. 18 could be used to form a capacitor merely by sprayillg~ thc righ~
and left hand longitudinal edges of the segment with a metallix,ed spray, such as babbitt or other suitable metal, in accordance with conventional practice, and then electrical leads could be secured to them, for ex-ample. by soldering. ~lternately, the capacitor .segment of Fig. 18 could be cut along a transverse line, such as the line 243~ and a number Case :316 8-~0 ~ 3~
of such segments could be stacked upon eacll other, witll thc CIO~Vll-wardly facing margin 218 of one capacitor segment being adjacent to and aligned with a corresponding upwardly facing margin 218' of the capacitor segment that is positioned immediately below it, as sho~vn diagrammatically by the dotted line representative of Fig. 18, and then their ends could be sprayed with a metallized spray and leads could then be secured to the stacl;ed array of such segments. In conjunction with the presently preferred embodiment OI the present invention, how-ever, Fig. 19 represents two layers of a capacitor segment formed by '~ winding of the dielectric strip about the center of the longitudinal dimen-sion of the strip 210, as shown in Fig. 19, So form a wound capacitor seg-ment. Another version of this capacitor coi~ be achieved, ho\v~ver, by pleating~ instead ol winding, the capacitor segment of Fig. 18 a number of times along transverse fold lines such as the line 243. ~1ternate1y, the capacitor segment could be pleated transversely two or more times ~bout transverse lines~ such as the line 243, and then the segment could be comp1eted by windin~ the remainder of the length of the ` dielectric strip.
~he winding of the capacitor segment of Fig. 18 into a ~ und 1~ capacitor may be achieved with various winding techniques, including the use of a split mandrel such as the mandrel 256 of Fig. 19, which is removed from the capacitor segment after it has been wound. An unmet-allized dielectric strip (not shown) may be wound around the str~lcture to f~ :
Case 316~-20 ~0~3~
form an outer protective coating. ~his dielectric strip may be heat-sealed to itself to form the pleated capacitor segment, as shown in Fig. 6. ~he removal of the mandrel 56 from the capacitor segment leaves an opening in the unit. ~he opening may again be closed by applying pressure, or pressure and heat, in accordance with thc type of dielectric layer used and conventional manufacturing techniques to the capacitor segment so that it assumes an oval shape, as shown in l~ig. 7.
Once the capacitor segment has been wound, a metallized spray may then be directed against the longitudinal edges of tlle unit il~
accordance with conventional processing techniques to interconnect the electrode layers along these edges and to provide for the connection of electrical leads to the unit. The r~letallized spray will penetrate into the open area between the margin 216 areas Oll the left hand longitudinal edge of the capacitor segment, as shown diagrammatically in Fig. 18 to a depth such as that indicated by the plane 26G, so as to make contact with the electrode area 220. ~he plane 26G indicates the maximum depth that any high velocity spray particles will penetrate and it may thus be located any place between the end oE the margin 216 2Q areas of the metallized strip 210 and the edge of the pleat 252.
Accordingly, the metallized spray material will exlell(l into tlle left hand opening of the capacitor between the margill 216 areas far enougll to make contact to the facing metallized electrode on the other side of the dielectric strip, but not so far that it will penetrate through the ~5 dielectric material at the pieat 252.
- 22 ~
Case ~1G8-20 1.~ i6 ~erlllination to the right halld longitudinal eclge of the capacitor segment of Fig. 18 is similarly provided ~y a metallized spray which extends over the margin 218 area to a depth, such as that indicated by the plane 268, which is sufficient to allow the metallized spray to make good contact to the electrode 214 on the inside of the margin 218 area but ~VhiCIl ~vill prevent the penetration of the spray metallic par-ticles through the dielectric at the pleat 242. ~he location o~ thc plane
2~8 may be anywhere between the edges of the pleat 242 and the end of the margin area 218 as long as there is sufficient depth of ~p ray to pro-vide adequate contact termination to the electrode area 214. Ihe con-figuration of the present invention thus provides for reliable lead ter-mination at the longituc~inal edges of the capacitor segm~llt ot` I~`ig. 1~
without the necessity of providing unmetallized longitudinal strips alollg the inside of the pleats 242, 252, thereby saving considerable processing expenses in the manufacture of completed capacitors of this type.
Once the metallic spray has been applied to the edges of the capacitor segment, either radial or a~ial leads lllay l e ap plicd to it, again as previously shown in Figs. 7 and 8.
Another alternate version of the present invention is shown in Fig. 20, wherein two layers of either a wound or a stacked capacitor segment is shown. Ihis version differs from that shown in Fig. 18 in that intermediate dielectric layers 269, 269' are inserted between alternating groups 271, 273 of pleated layers of the capacitor segment ~,~h ich face in opposite directions. If the capacitor of Fig. 20 is to be a wound embodi-~5 ment, the alternating groups 271, 273 of pleated layers which face in opposite directions may each be supplied from a different pleated seg-ment supply.
Case 31~-20 ~0~3~ ~6 rhe previously described embodiments oî the present invention are illustrative, but not exhaustive, of the various types of configurations that may come within the scope of the present invention. For instance, while winding about the exact center of the dielectric strip is prefe~red, it is apparent that winding about any number of transverse lines offset from the centerJ but intermediate the ends of the dielectric strip, are intended to be included within the scope of the present invention. It is also further apparent that more than two longitudinal pleat lines may be employed in the version shown in Fig. 18 wi~hin the scope of the present invention.
without the necessity of providing unmetallized longitudinal strips alollg the inside of the pleats 242, 252, thereby saving considerable processing expenses in the manufacture of completed capacitors of this type.
Once the metallic spray has been applied to the edges of the capacitor segment, either radial or a~ial leads lllay l e ap plicd to it, again as previously shown in Figs. 7 and 8.
Another alternate version of the present invention is shown in Fig. 20, wherein two layers of either a wound or a stacked capacitor segment is shown. Ihis version differs from that shown in Fig. 18 in that intermediate dielectric layers 269, 269' are inserted between alternating groups 271, 273 of pleated layers of the capacitor segment ~,~h ich face in opposite directions. If the capacitor of Fig. 20 is to be a wound embodi-~5 ment, the alternating groups 271, 273 of pleated layers which face in opposite directions may each be supplied from a different pleated seg-ment supply.
Case 31~-20 ~0~3~ ~6 rhe previously described embodiments oî the present invention are illustrative, but not exhaustive, of the various types of configurations that may come within the scope of the present invention. For instance, while winding about the exact center of the dielectric strip is prefe~red, it is apparent that winding about any number of transverse lines offset from the centerJ but intermediate the ends of the dielectric strip, are intended to be included within the scope of the present invention. It is also further apparent that more than two longitudinal pleat lines may be employed in the version shown in Fig. 18 wi~hin the scope of the present invention.
Claims (23)
1. An electrical capacitor segment comprising a dielectric layer having a center line, a first metallized electrode layer applied to one side of said dielectric layer so that an unmetallized margin extends along each edge of a pair of parallel edges of said dielectric layer, a second metallized electrode layer applied to the other side of said dielectric layer so that an unmetallized area is located ad-jacent said second metallized electrode layer, said dielectric layer being pleated once along said unmetallized areas off of said center line so that one edge of said margin containing edges extends beyond the other of said edges along the same end of said capacitor segment and metallized spray material in contact with said second electrode layer.
2. An electrical capacitor comprising a plurality of capacitor segments that are stacked upon each other wherein each capacitor segment comprises a dielectric layer having a center line, a first metallized electrode layer applied to one side of said dielectric layer so that an unmetallized margin extends along each edge of a pair of parallel edges of said dielectric layer, a second metallized electrode layer applied to the other side of said dielectric layer so that an unmetallized area is located adjacent said second metallized electrode layer, said dielectric layer being pleated once along said unmetallized area off of said center line so that one edge of said margin containing edges extends beyond the other of said edges along the same end of its associated capacitor segment and metallized spray material in contact with said second electrode layer, wherein said metallized end spray is applied to said capacitor segments after they have been stacked upon each other.
3. An electrical capacitor segment comprising a dielectric layer having a center line, a first metallized electrode layer applied to one side of said dielectric layer so that an unmetallized margin extends along each edge of a pair of parallel edges of said dielectric layer, second and third metallized electrode areas applied to the other side of said dielectric layer so that a centrally located unmetallized strip runs between said metallized areas, said dielectric layer being pleated once along said unmetallized center strip slightly off of said center line so that one edge of said margin containing edges extends beyond the other of said edges along the same end of said capacitor segment wherein said extension is sufficient in length to allow metallized spray material to make contact with at least one of said second and third electrode areas.
4. An electrical capacitor comprising a plurality of capacitor segments that are stacked upon each other wherein each capacitor segment comprises a dielectric layer having a center line, a first metallized electrode layer applied to one side of said dielectric layer so that an unmetallized margin extends along each edge of a pair of parallel edges of said dielectric layer, second and third metallized electrode areas applied to the other side of said dielectric layer so that a centrally located unmetallized strip runs between said metallized areas, said dielectric layer being pleated once along said unmetallized strip slightly off of said center line so that one edge of said margin containing edges extends beyond the other of said edges along the same end of its associated capacitor segment wherein said extension is sufficient in length to allow metallized spray material to make contact with at least one of said second and third electrode areas, wherein said metallized end spray is applied to said capacitor segments after they have been stacked upon each other.
5. An electrical capacitor segment comprising a di-electric layer having a center line, a first metallized electrode layer applied to one side of said dielectric layer so that an unmetallized margin extends along each edge of a pair of parallel edges of said dielectric layer, second and third metallized electrode layers applied to the other side of said dielectric layer so that a centrally located unmetallized strip runs between said second and third metallized layers, said dielectric layer being pleated once along said unmetallized center strip slightly off of said center line so that one edge of said margin containing edges extends beyond the other of said edges along the same end of said capacitor segment and a first metallized spray material in contact with only one of said second or third electrode layers at said same end of the segment, with said first electrode area having a second metallized spray material at the other end of the segment.
6. An electrical capicitor comprising a plurality of capacitor segments that are stacked upon each other wherein each capacitor segment comprises a dielectric layer having a center line, a first metallized electrode layer applied to one side of said dielectric layer so that an unmetallized margin extends along each edge of a pair of parallel edges of said dielectric layer, second and third metallized electrode layers applied to the other side of said dielectric layer so that a centrally located unmetallized strip runs between said metallized layers, said dielectric layer being pleated once along said unmetallized strip slightly off of said center line so that one edge of said margin containing edges extends beyond the other of said edges along the same end of its associated capacitor segment and a first metallized spray material in contact with only one of said second or third electrode layers at the same end of the segments with said first electrode having a second metallized spray material at the other end of the segments.
Claim 7. An electrical capacitor segment as claimed in Claim 1, wherein said dielectric layer is an elongated layer and said capacitor segment is wound about the center of said dielectric strip along the elongated dimension of said layer subsequent to said pleating along longitudinal pleat lines and said metallized sprayed material is applied to the ends of said capacitor after said winding has been completed.
Claim 8. An electrical capacitor segment as claimed in Claim 3, wherein said dielectric layer is an elongated layer and said capacitor segment is wound about the center of said dielectric strip along the elongated dimension of said layer subsequent to said pleating along longitudinal pleat lines and said metallized sprayed material is applied to the ends of said capacitor after said winding has been completed.
Claim 9. An electrical capacitor segment as claimed in Claim 5, wherein said dielectric layer is an elongated layer and said capacitor segment is wound about the center of said dielectric strip along the elongated dimension of said layer subsequent to said pleating along longitudinal pleat lines and said metallized sprayed material is applied to the ends of said capacitor after said winding has been completed.
Claim 10. An electrical capacitor segment as claimed in Claim 1, wherein said dielectric layer is an elongated layer and said capacitor segment is pleated along lines transverse to the elongated dimension of said layer subsequent to said pleating along longitudinal pleat lines and said metallized sprayed material is applied to the ends of said capacitor after said transverse pleating has been completed.
Claim 11. An electrical capacitor segment as claimed in Claim 3, wherein said dielectric layer is an elongated layer and said capacitor segment is pleated along lines transverse to the elongated dimension of said layer subsequent to said pleating along longitudinal pleat lines and said metallized sprayed material is applied to the ends of said capacitor after said transverse pleating has been completed.
Claim 12. An electrical capacitor segment as claimed in Claim 5, wherein said dielectric layer is an elongated layer and said capacitor segment is pleated along lines transverse to the elongated dimension of said layer subsequent to said pleating along longitudinal pleat lines and said metallized sprayed material is applied to the ends of said capacitor after said transverse pleating has been completed.
13. An electrical capacitor as claimed in Claim 2, wherein alternating ones of said plurality of capacitor segments face in opposite directions and are separated from their neighboring segments by dielectric material.
14. An electrical capacitor as claimed in Claim 4, wherein alternating ones of said plurality of capacitor segments face in opposite directions and are separated from their neighboring segments by dielectric material.
15. An electrical capacitor as claimed in Claim 6, wherein alternating ones of said plurality of capacitor segments face in opposite directions and are separated from their neighboring segments by dielectric material.
16. An electrical capacitor segment as claimed in Claim 1, further comprising a third metallized electrode area applied to the same side of said dielectric layer as said second metallized electrode area.
17. An electrical capacitor as claimed in Claim 2 further comprising a third metallized electrode area applied to the same side of said dielectric layer as said second metallized electrode area.
18. An electrical capacitor as claimed in Claim 1, Claim 2 or Claim 3, wherein a lead is secured to each of said metallized sprayed ends of said capacitor segment.
19. An electrical capacitor as claimed in Claim 4, Claim 5 or Claim 6, wherein a lead is secured to each of said metallized sprayed ends of said capacitor segment.
20. An electrical capacitor as claimed in Claim 7, Claim 8 or Claim 9, wherein a lead is secured to each of said metallized sprayed ends of said capacitor segment.
21. An electrical capacitor as claimed in Claim 10, Claim 11 or Claim 12, wherein a lead is secured to each of said metallized sprayed ends of said capacitor segment.
22. An electrical capacitor as claimed in Claim 13, or Claim 14, wherein a lead is secured to each of said metallized sprayed ends of said capacitor segment.
23. An electrical capacitor as claimed in Claim 15, Claim 16 or Claim 17, wherein a lead is secured to each of said metallized sprayed ends of said capacitor segment.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA360,216A CA1109935A (en) | 1977-07-12 | 1980-09-12 | Metallized film capacitors |
| CA360,215A CA1105578A (en) | 1977-07-12 | 1980-09-12 | Metallized film capacitors |
Applications Claiming Priority (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US05/814,954 US4128857A (en) | 1977-07-12 | 1977-07-12 | Pleated metallized film capacitor wound about its center |
| US814,945, | 1977-07-12 | ||
| US814,958 | 1977-07-12 | ||
| US05/814,945 US4127890A (en) | 1977-07-12 | 1977-07-12 | Single pleat metallized film capacitor with sprayed edge terminations |
| US814,954 | 1977-07-12 | ||
| US05/814,958 US4127891A (en) | 1977-07-12 | 1977-07-12 | Pleated metallized film capacitor with sprayed edge terminations |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1093166A true CA1093166A (en) | 1981-01-06 |
Family
ID=27420100
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA305,939A Expired CA1093166A (en) | 1977-07-12 | 1978-06-21 | Metallized film capacitors |
Country Status (9)
| Country | Link |
|---|---|
| JP (1) | JPS5441453A (en) |
| BR (1) | BR7804182A (en) |
| CA (1) | CA1093166A (en) |
| DE (1) | DE2830423A1 (en) |
| FR (1) | FR2397708A1 (en) |
| GB (3) | GB2067016B (en) |
| IT (1) | IT1096938B (en) |
| MX (1) | MX144868A (en) |
| NL (1) | NL7807154A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19548501A1 (en) * | 1995-12-22 | 1997-01-16 | Hsp Hochspannungsgeraete Porz | High voltage capacitor formed from strip dielectric band - has metal layers on both sides that have isolating gaps with band folded into zig=zag pattern |
-
1978
- 1978-06-21 CA CA305,939A patent/CA1093166A/en not_active Expired
- 1978-06-27 FR FR7819120A patent/FR2397708A1/en active Pending
- 1978-06-30 BR BR7804182A patent/BR7804182A/en unknown
- 1978-06-30 NL NL7807154A patent/NL7807154A/en not_active Application Discontinuation
- 1978-07-07 MX MX174094A patent/MX144868A/en unknown
- 1978-07-10 IT IT25481/78A patent/IT1096938B/en active
- 1978-07-11 DE DE19782830423 patent/DE2830423A1/en not_active Withdrawn
- 1978-07-11 JP JP8366478A patent/JPS5441453A/en active Pending
- 1978-07-12 GB GB8013611A patent/GB2067016B/en not_active Expired
- 1978-07-12 GB GB7829582A patent/GB2001199B/en not_active Expired
-
1979
- 1979-07-12 GB GB8013604A patent/GB2066572B/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| IT1096938B (en) | 1985-08-26 |
| BR7804182A (en) | 1979-04-10 |
| GB2067016B (en) | 1982-08-11 |
| MX144868A (en) | 1981-11-27 |
| GB2067016A (en) | 1981-07-15 |
| NL7807154A (en) | 1979-01-16 |
| JPS5441453A (en) | 1979-04-02 |
| IT7825481A0 (en) | 1978-07-10 |
| FR2397708A1 (en) | 1979-02-09 |
| GB2066572B (en) | 1982-08-11 |
| DE2830423A1 (en) | 1979-01-25 |
| GB2001199A (en) | 1979-01-24 |
| GB2001199B (en) | 1982-05-26 |
| GB2066572A (en) | 1981-07-08 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |