KR101029514B1 - coil - Google Patents

Abstract

The metal coil sheets 34, 36, 38 are planar in shape and include center windows 34a, 36a, 38a. Slits 34b, 36b, 38b extend outwards through respective sheets from the windows. The sheets are provided with connection terminals 34c, 34d; 36c, 36d; 38c, 38d at opposite positions with each slit interposed therebetween. Metal coil sheets are laminated, and adjacent metal coil sheets are electrically connected by connecting terminals. Cores 60 and 62 are disposed in the windows of the stacked metal coil sheets. Metal coil sheets are individually coated by an insulating coating.

Description

Coil

1 is an exploded perspective view of a prior art transformer;

2 is an exploded perspective view of a transformer according to a first embodiment of the present invention;

3a to 3d are views showing the steps of manufacturing a metal coil sheet that can be used in the transformer shown in FIG.

4A is a plan view of a metal coil sheet usable in the transformer of FIG. 2;

4B is a cross-sectional view taken along line 4b-4b of the metal coil sheet shown in FIG. 4A;

4C is a cross-sectional view along line 4c-4c of the metal coil sheet shown in FIG. 4a;

5A is a cross-sectional view of a metal coil sheet that can be used in the transformer of FIG. 2;

5B is a cross-sectional view of a metal coil sheet used in a prior art transformer; And

6 is an exploded perspective view of a choke manufactured using the coil of the present invention.

Explanation of symbols on the main parts of the drawings

1, 2, 3, 4, 5, 6: metal coil sheet

1a, 2a 3a, 4a, 5a, 6a: windows

1b, 2b, 3b 4b, 5b, 6b: slit

1c, 2c, 3c, 4c, 5c, 6c, 1d, 2d, 3d, 4d, 5d, 6d: tab

9, 10, 11, 14, 17: insulation sheet                 

9a, 10a, 11a, 14a, 17a: center window

18, 19: core half

18a, 19a, 60a, 62a: center leg

18b, 18c, 19b, 19c, 60b, 60c, 62b, 62c: home

18d, 18e, 19d, 19e, 60d, 60e, 62d, 62e: outer leg

30, 32: winding

34, 36, 38, 40, 42, 44: metal coil sheet

34a, 36a, 38a, 40a, 42a, 44a: windows

34b, 36b, 38b, 40b, 42b, 44b: slit

34c, 36c, 38c, 34d, 36d, 38d, 40c, 42c, 44c, 40d, 42d, 44d: terminals

46: insulation film

59: copper sheet

52, 54: hole

56: polyimide film

58: epoxy resin layer

60, 62: core

The present invention relates to a coil that may be used, for example, as a component of a transformer or as a choke. The applicant of this application filed the high frequency high current transformer of this specification (published as US-2002-0070836-A1 on June 13, 2002) on December 6, 2001 in US Patent Application No. 10 / 006,478. The transformer disclosed in the US application comprises metal, for example copper coil sheets or planar coil members 1, 2, 3, 4, 5, 6, as shown in FIG. 1. The metal coil sheets 1, 2, 3, 4, 5, 6 are formed in a rectangular shape having windows 1a, 2a, 3a, 4a, 5a, 6a in the center thereof. One side of each coil sheet is cut | disconnected, and forms the slit 1b, 2b, 3b, 4b, 5b, 6b. The tabs 1c and 1d extend outward from the opposing portions with the slit 1b interposed therebetween. Similarly, tabs 2c and 2d, 3c and 3d and 4c from portions of respective coil sheets 2, 3, 4, 5 and 6 opposing each other with slits 2b, 3b, 4b, 5b and 6b in between. And 4d, 5c and 5d, 6c and 6d) extend outward. The tabs 1c, 2c, 3c, 4c, 5c, 6c are winding start terminals, and the tabs 1d, 2d, 3d, 4d, 5d, 6d are winding end terminals. The coil sheets 1, 2, 3 are stacked with the tabs 1d, 2c connected to each other and the tabs 2d, 3c connected to each other, thereby providing a primary winding of the transformer. Similarly, the coil sheets 4, 5, 6 are stacked with tabs 4c, 5c, 6c connected to each other and tabs 4d, 5d, 6d connected to each other, thereby providing a secondary winding. The insulating sheets 9, 10, 11, 14 are arranged in such a manner that each coil sheet 1, 2, 3 is sandwiched between two insulating sheets. The insulating sheet 17 is disposed on the laminate of the coil sheets 4, 5, 6, and the laminate of the coil sheets 4, 5, 6 is sandwiched between the insulating sheets 17, 14. The insulating sheets 9, 10, 11, 14, 17 have center windows 9a, 10a, 11a, 14a, 17a, respectively. Also, for example, two core halves 18 and 19 of ferrite are used. The core halves 18 and 19 have center legs 18a and 19a, and grooves 18b and 18c, 19b and 19c are formed on both sides of the center legs 18a and 19a. Outer legs 18d and 18e are formed outside the grooves 18b and 18c, respectively, and outer legs 19d and 19e are formed outside the grooves 19b and 19c, respectively. The center legs 18a and 19a can be extended and positioned through the center windows 1a to 6a of the coil sheets 1 to 6 and the center windows 9a to 14a and 17a of the insulating sheets 9 to 14 and 17. The core halves 18, 19 are combined.

When manufacturing such a transformer, it is necessary to alternately stack a metal coil sheet and an insulating sheet, which increases the manufacturing cost of the transformer. In this arrangement, since the metal coil sheet is exposed to air, oxidization may occur after prolonged use. In addition, in order to satisfy the safety standard for the transformer, the insulation sheets 9, 10, 11, 14, and 17 are arranged so as to maintain sufficient creepage distance even when the insulation sheets are slightly displaced with respect to the metal coil sheets. Should be. For this purpose, a larger insulating sheet must be used, which makes the transformer large in size.

It is an object of the present invention to provide a coil having a small number of working steps, difficult to oxidize and small in size.

The coil according to an embodiment of the present invention includes a coil part having a plurality of metal coil sheets. The coil sheets are planar in shape and each has a window in the center thereof. In addition, slits are formed in each coil sheet, and the slits extend from the position around the window to the outer periphery of the sheet through the sheet. Connection terminals are formed at positions in the sheet facing each other with the slits interposed therebetween. The coil sheets are stacked, and adjacent coil sheets are electrically connected to each other by connecting terminals. In addition, a core is disposed in the window of the coil sheets. Each of the metal coil sheets is individually covered with an insulating coating before being laminated.

In the above configuration, since each metal coil sheet of the coil is individually coated with an insulating film, it is not necessary to arrange the insulating sheet between adjacent coil sheets when the metal coil sheets are laminated, thereby reducing the manufacturing process and Therefore, manufacturing cost can be reduced. In addition, by covering the entire surface of each metal coil sheet with an insulating film, the metal coil sheets are oxidized and rust hardly occurs. In addition, since each metal sheet is individually coated with an insulating film, it is not necessary to arrange the insulating sheets with respect to the metal coil sheets when laminating the metal coil sheets. Therefore, since it is not necessary to take such a displacement when calculating creeping distance, creeping distance can be set small. Therefore, the size of the transformer can be reduced.

Also, a plurality of coil parts may be used. The core is arranged to extend through the window of the metal coil sheet of the coil portion, and the plurality of coil portions are inductively coupled to each other. This configuration can be manufactured at low cost, is difficult to rust, and provides a small transformer.

The insulating film may be formed by applying an insulating resin directly on the metal coil sheet. Alternatively, before laminating the metal coil sheets, the insulating film may be adhered so as to apply part or all of the surface of the metal coil sheet. In addition, the insulating resin may be used as an adhesive for bonding the preformed insulating film to the metal coil sheet.

The present invention may be implemented in a high frequency high current transformer, as shown in FIG. The transformer comprises a plurality, for example two coil parts, or windings 30, 32.

The winding 30 comprises a plurality, for example, three metal coil sheets 34, 36, 38, which are formed in a rectangular shape and are the same size. Windows 34a, 36a, 38a are formed in the central region of the metal coil sheets 34, 36, 38, respectively. The windows 34a, 36a, 38a are the same size. The metal coil sheets 34, 36, 38 are formed of metal, for example, copper. Each coil sheet 34, 36, 38 includes slits 34b, 36b, 38b on one of the four sides around the window. Slits are formed on one side of the completed transformer, but the positions of the slits 34b, 36b, 38b are offset relative to each other. Terminals 34c and 34d are provided at portions of the coil sheet 34 facing each other with the slit 34b therebetween. Similarly, terminals 36c and 36d and terminals 38c and 38d are provided in opposing coil sheets 36 and 38 with respective slits 36b and 38b interposed therebetween. The terminals 34c, 36c, 38c are winding start terminals, and the terminals 34d, 36d, 38d are winding end terminals. The metal coil sheets 34, 36, 38 are laminated so that the windows 34a, 36a, 38a coincide with each other. The position of the slits 34b, 36b, 38b is determined so that when stacking the coil sheets, the terminals 34d, 36c coincide vertically and the terminals 36d, 38c coincide vertically.

The winding 32 includes metal coil sheets 40, 42, 44 configured identically to the metal coil sheets 34, 36, 38 of the winding 30. The metal coil sheets 40, 42, 44 have respective windows 40a, 42a, 44a, respective slits 40b, 42b, 44b, and respective terminal pairs 40c and 40d, 42c and 42d, 44c. And 44d). The metal coil sheets 40, 42, 44 are also laminated so that the windows 40a, 42a, 44a vertically coincide. When the metal coil sheets 40, 42, 44 are stacked, the positions of the slits 40b, 42b, 44b are determined so that the terminals 40d, 42c coincide vertically and the terminals 42d, 44c coincide vertically. do.

Each metal coil sheet 34, 36, 38, 40, 42, 44 has an insulating coating 46, as represented by the metal coil sheet 38 shown in detail in FIGS. 4A-4C. have. The insulating film 46 is coated on the entire surface of the metal coil sheet 38. FIG. 4B is a cross-sectional view along the 4b-4b line of the metal coil sheet 38 having the insulating film shown in FIG. 4A, and FIG. 4C is a cross-sectional view along the 4c-4c line.

The insulating film 46 is formed of an insulating film and an epoxy resin layer, and is formed as follows. First, a metal coil sheet 38 is formed by punching the copper sheet 50 along a dotted line, as shown in Fig. 3A. In this step, holes 52 and 54 are also formed in the terminals 38c and 38d, respectively. Subsequently, as shown in FIG. 3B, two insulating films having an insulating adhesive layer, for example, an epoxy resin layer 58, for example, a polyimide film 56, may be used for each polyimide film 56. Prepare by coating an epoxy resin on one surface of. The polyimide film 56 has a larger rectangular shape than the metal coil sheet 38.

When the epoxy resin layers 58 are partially dried, the polyimide film 56 is positioned by bringing the epoxy resin layer 58 into contact with the major surface of the metal coil sheet 38, as shown in FIG. 3C. ) Are joined so as to face two main surfaces of the metal coil sheet 38. Therefore, the metal coil sheet 38 is sandwiched in a sandwich shape. As can be seen from FIG. 3C, the terminals 38c and 38d are not covered by the polyimide film 56.

Then, as shown in FIG. 3D, the metal coil sheet 38 is applied by applying pressure upward and downward to the polyimide film 56 by a press (not shown), for example, a press having a silicone rubber pressing surface. ), The metal coil sheet 38 and the polyimide film 56 are heated at a temperature between about 150 ° C and about 180 ° C for 3 to 5 hours to cure the epoxy resin layer 58. Thereafter, unnecessary portions of the peripheral and central portions of the polyimide film 56 and the epoxy resin layer 58 are punched out to remove the metal coil sheet 38 having the polyimide film 56 as shown in FIG. 4A. It becomes The holes 52, 54 of the terminals 38c, 38d are used for the positioning of the metal coil sheet 38 for this punching step. Other metal coil sheets have an insulating coating in the same manner as described above. 3A-3D and 4A-4C show the thickness of the polyimide film 56 and the epoxy resin layer 58 exaggerated.

The metal coil sheets 34, 36, 38 having respective insulating films formed in the above-described manner have a terminal 36c disposed on the terminal 34d and a terminal 38c disposed on the terminal 36d. Stacked in such a way that the windings 30 are formed. Similarly, the metal coil sheets 40, 42, 44 having respective insulating films formed in the manner described above have a terminal 42c disposed on the terminal 40d and a terminal 44c disposed on the terminal 42d. Are stacked in such a way that the windings 32 are formed. The terminals 34d and 36c of the winding 30 are electrically connected to each other, and the terminals 36d and 38c are also electrically connected. Similarly, the terminals 40d and 42c of the winding 32 are electrically connected to each other, and the terminals 42d and 44c are also electrically connected to each other.

The two windings 30, 32 are vertically aligned with windows 34a, 36a, 38a, 40a, 42a, 44a, for example, a winding in which ferrite cores 60, 62 are stacked vertically. It is laminated | stacked by the method arrange | positioned at the sandwich shape above and below (30,32). More specifically, the upper core 60 has a center leg 60a, two outer legs 60d and 60e, and between the center leg 60a and the outer leg 60d and between the center leg 60a and the outer side. It has grooves 60b and 60c between the legs 60e, respectively. Similarly, the lower core 62 has a center leg 62a, two outer legs 62d and 62e, and a center leg 62a and an outer leg 62d, and a center leg 62a and an outer leg 62e. Have grooves 62b and 62c, respectively. When the cores 60, 62 are disposed above and below the stacked windings 30, 32, the center legs 60a, 62a are disposed in the windows 34a, 36a, 38a, 40a, 42a, 44a, each Two opposing sides of the metal coil sheets 34, 36, 38, 40, 42 and 44 are disposed in respective spaces formed by the grooves 60b, 60c, 62b and 62c.

5A is a cross-sectional view of a metal coil sheet 38 having an insulating coating 46. FIG. 5B is a cross-sectional view of the metal coil sheet 2 (FIG. 1) of the prior art which does not have an insulation film such as the insulation film 46, for example, insulated by the insulation sheets 10, 11. The metal coil sheets 38 and 2 have the same size. As can be seen from FIG. 5B, the metal coil sheet 2 of the prior art is used to secure the creepage distance required when the position of the coil sheet 2 with respect to the insulating sheets 10, 11 deviates from the nominal position. Large insulating sheets are required to provide a long creepage distance "a". On the other hand, according to the present invention, as shown in Fig. 5A, since the metal coil sheet 38 is bonded to the insulating film 46, the creepage distance " b " can be set only as necessary and needs to be longer than necessary. none. The shorter the creepage distance, the smaller the transformer can be. In addition, since the metal coil sheets are individually covered with the insulating film (polyimide film) 56, the work of arranging the insulating sheets between adjacent metal coil sheets can be eliminated, thereby reducing the manufacturing cost. In addition, since the insulating film (polyimide film) 56 completely covers the metal coil sheets 38 individually, the sheets 38 can be prevented from rusting.

6 shows a coil according to the invention used to form a high frequency choke. The structure of the high frequency choke is the same as removing the winding 30 from the transformer shown in FIG. Therefore, the same reference numerals used in FIG. 2 are used for the same portions, and detailed description of the chalk is omitted.

Instead of the two windings 30, 32 used in the transformer shown in FIG. 2, more windings may be used to form a transformer with one primary winding and a plurality of secondary windings. In addition, instead of polyimide and epoxy, other materials may be used as the insulating film and the insulating adhesive.

According to the coil according to the present invention, it is possible to provide a coil having a small number of working steps, difficult to oxidize, and small in size.

Claims (6)

A coil portion including a plurality of metal coil sheets each having a planar shape, and having a center window and a slit extending from the window to its outer edge and having connection terminals at positions facing each other with the slit interposed therebetween, The plurality of metal coil sheets are laminated, and coil parts in which adjacent metal coil sheets are electrically connected to each other by the connection terminals; And A core having a central leg disposed in said window of said laminated metal coil sheets, Each of the metal coil sheets is individually coated with an insulating coating before being laminated, Each said insulating film arrange | positions the preformed two planar insulating film which is larger in size than the said metal coil sheet above and below the said metal coil sheet, between which the insulating resin was apply | coated, and pressure and heat And attaching the metal coil sheet and the insulating film so that a portion corresponding to the window is removed later. A transformer comprising a plurality of coil parts according to claim 1, wherein said center leg of said core is disposed in said windows of said stacked metallic coil sheets of said plurality of coil parts. delete delete delete delete

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