JPH0917640A - Element assembling member of transformer and pot core transformer - Google Patents

Abstract

PURPOSE: To provide a pot core transformer of high productivity wherein magnetic flux generated by a sheet coil does not leak. CONSTITUTION: In a pot core 1, a ring type trench 11 is formed in a magnetic cylinder, an aperture part 7 is formed in the upper part, and slits 4 penetrating from the bottom of the trench 11 to the lower part of the core are formed. A sheet coil is punched out of a spiral type conducting foil having through holes 21 formed at both ends, buy one stamping with a press. The surface is coated with insulator. A connection board 5 provided with connection terminals 51 is fixed to the lower surface of the bottom part of the pot core 1. The sheet coil 2 is accommodated in the trench 11 of the pot core 1l. Pins 3 are inserted in the slits 4. The insertion ends are connected with the connection terminals 51. Hence the element assembling member of a transformer is constituted. A primary side assembling member and a secondary side assembling member which are different in the number of the sheet coils 2 are mutually coupled in the aperture part 7. Thereby a pot core transformer is constituted.

Description

Detailed Description of the Invention

[0101]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high frequency pot core transformer and is suitable for a DC-DC converter.

[0092]

2. Description of the Related Art As a first conventional technique, a rectangular shape in which sheet coils each having a connecting portion, in which a coil pattern is formed by etching or plating on a thin insulating sheet sandwiched between both legs of an E-shaped core, are laminated. And a pin-shaped connecting conductor inserted into a through hole formed in each connecting portion provided at the end of this laminated body (for example, Japanese Patent Laid-Open No. 61-75510).

[0093]

However, in the prior art, since the connecting portions are provided at the ends of the laminated body, the magnetic flux generated by the coil end of the sheet coil protruding from the core leaks and becomes an ineffective magnetic flux. . Further, since the coil pattern is formed by etching or plating the sheet coil on a thin insulating sheet, there is a problem that productivity is poor. Therefore, an object of the present invention is to provide a highly productive pot core transformer in which the magnetic flux generated by the sheet coil does not leak.

[Means for Solving the Problems] A core of a magnetic material, a sheet coil in which through holes 21 are provided at the beginning and the end of a spiral conductor foil, and the sheet coil is housed in the core and the through hole is formed. In the element assembly of the transformer provided with the conductor pin 3 for inserting the core 21, the core is provided with the ring-shaped groove 11 in the magnetic cylindrical body, and the opening 7 is formed in the upper part.
A slit 4 penetrating from the bottom of the groove 11 to the bottom of the core.
And a connection board 5 having connection terminals 51 on the bottom surface of the bottom of the pot core 1 is provided. The sheet coil 2 is housed in the groove 11 of the pot core 1, the pin 3 is inserted through the slit 4, and the insertion end is connected to the connection terminal 51 to form a transformer element assembly. The element assembly of this transformer is made up of two sets of the primary side and the secondary side of which the number of the sheet coils 2 is different, and these two sets of the element assembly of the transformer are connected at the opening 7 to form a pot core transformer. . As another embodiment, the opening 7 of the pot core 1 is covered with the core 8 and the through hole 21 is formed.
Is a sheet coil 2A, 2B provided on the outside of the inner and outer diameters of the sheet coil 2, and the sheet coils 2A, 2B are superposed on each other, or the small-diameter sheet coil 2B is fitted on the inner diameter side of the large-diameter sheet coil 2A. Is stored in the groove 11.

[0093]

By the above means, the entire sheet coil is enveloped by the pot core. The sheet coil is punched with one stamp by the press, and the productivity is improved.

[0056]

Embodiment An embodiment of the present invention will be described below with reference to FIG. FIG. 1 is a front sectional view showing an element assembly of a transformer (a) and a plan view showing a sheet coil (b) showing an embodiment. The element assembly of the transformer comprises a pot core 1, a sheet coil 2, pins 3 and a substrate 5. Pot core 1
Has a ring-shaped groove 11 having an opening 7 in the upper part of the magnetic cylindrical body, an inner core 12 on the inner diameter side, and an outer core 13 on the outer diameter side. At the bottom of the groove 11, the pot core 1
A slit 4 penetrating from the bottom of the groove 11 to the lower portion of the pot core 1 is provided at one location of the bottom of the groove 11 so that the connecting end of the pin 3 can be inserted with a wall surface of the slit 4 with a gap.
The sheet coil 2 is made of a conductor foil such as copper or aluminum whose inner diameter side is larger than the outer diameter of the inner core 12 and whose outer diameter side is smaller than the inner diameter of the outer core 13. Punching with, through holes 21, 21 are provided on the same radiation at the start and end of the spiral, and the through hole 2
The surfaces except 1 and 21 are formed by coating with an insulating agent. A predetermined number of sheet coils 2 are stacked and stored in the groove 11. A pin 3 made of a conductive material and having a length extending outward from the bottom surface of the pot core 1 is inserted into each of the starting end and the terminating end of the through holes 21, 21. The connection end of the pin 3 protruding from the bottom of the pot core 1 is connected to the connection terminal 51 provided on the connection substrate 5 fixed to the bottom of the pot core 1 by adhesion or the like. The lead 6 is connected to the other end of the connection terminal 51 to form a transformer element assembly. After the assembly of the element assembly of the transformer is completed, the groove 11 may be molded with resin for insulation, strength and cooling. In the element assembly of this transformer, the number of laminated sheet coils 2 is N1.
The primary side and the secondary side in which the number of laminated sheet coils 2 is N2 are made, and each set is coupled at the opening 7 to form a pot core transformer having an output voltage of N2 / N1.

FIG. 2 is a front sectional view of a pot core transformer (a) and a plan view of a sheet coil (b) showing a second embodiment. In this example, the groove 1 is formed on the primary side and the secondary side of the sheet coil.
It is stored in a stack in one. Pot core 1
The opening 7 is covered with a disk-shaped core 8. The sheet coils 2A and 2B on the primary side and the secondary side have substantially the same structure as the sheet coil 2 of the embodiment. The difference is in the positions where the through holes are provided. Each of the through holes 21 is located outside the outer diameter of the inner core 12 on the outer diameter side of the sheet coils 2A, 2B and on the inner diameter side of the sheet coils 2A, 2B. It is provided inside the inner diameter of the core 13. N1 sheets of the primary side sheet coil 2A and N2 sheets of the secondary side sheet coil 2B are housed in the groove 11 by superposing them in the groove 11 by shifting the radial position of each through hole 21 by 180 °, for example. To do. Two slits 4 are provided at the bottom of the pot core 1 corresponding to the shifted positions. The sheet coil 2A on the primary side and the sheet coil 2B on the secondary side each have a pin 3A on the primary side and a pin 3B on the secondary side inserted through the through holes 21. The substrate 5 has a connection terminal 5 on the primary side.
1A and the connection terminal 51B on the secondary side are provided so as to correspond to the position of the slit 4. With such a configuration, it becomes compact.

FIGS. 3A and 3B are (a) a front sectional view of a pot core transformer and (b) a plan view of a sheet coil, showing a third embodiment. In this example, the sheet coil 2C on the primary side and the sheet coil 2D on the secondary side are provided side by side in the groove 11 of the second embodiment. Similar to the embodiment, the sheet coil 2C on the primary side is provided with through holes 21 and 21 at the start end and the end, the inner diameter of the spiral is made larger than the outer diameter of the secondary sheet coil 2D, and the outer diameter of the outer core 13 is made larger. It is smaller than the inner diameter. Similar to the embodiment, the secondary side sheet coil 2D is provided with through holes 21 and 21 at the starting end and the terminating end, the inner diameter of the spiral is made larger than the outer diameter of the inner core 12, and the outer diameter is the primary side sheet coil. It is smaller than the outer diameter of 2C. The N2 sheets of the secondary side sheet coil 2D are fitted to the inner diameter side of the N1 sheets of the primary side sheet coil 2C.
And secondary side pins 3B and 3B respectively through holes 2
Insert 1 Similar to the embodiment, the substrate 5 is provided with the primary side connection terminal 51A and the secondary side connection terminal 51B in the slit 4.
It is provided corresponding to the position of.

FIG. 4A shows a flat coil of the fourth embodiment,
A side view and a (b) plan view are shown. In this example, the sheet coil 2 of the embodiment is replaced with a flat coil 25 in which a conductive wire having a thin insulating coating is spirally wound, and coil ends 26, 26 are perpendicular to the flat surface at the start and end of the spiral. It is bent in the direction. On the primary side, N1 flat plate coils 25 are stacked and housed in the groove 11 of the pot core 1 in the same manner as in the embodiment, the second embodiment and the third embodiment, and the slit 4 (N1 * 2) is used. ) Pull out the coil ends 26 of the book and connect each to the connection terminal 51 (or 51A). Similarly to the primary side, the secondary side is formed by laminating N2 flat plate coils 25,
The (N2 * 2) coil ends 26 are connected to the connection terminals 51 (or 51B). With such a configuration, connection of the coil end 25 to the connection terminal is troublesome, but an inexpensive conductor can be used.

[0099]

The above-mentioned structure has the following effects. (1) Since the entire sheet coil is enveloped by the pot core, the magnetic flux generated by the sheet coil does not leak. (2) Since the sheet coil is formed by punching out a conductive foil, the productivity is good.

[Brief description of the drawings]

FIG. 1A is a front sectional view of an element assembly of a transformer, and FIG. 1B is a plan view of a sheet coil, showing an embodiment of the present invention.

FIG. 2A is a front sectional view of a pot core transformer and FIG. 2B is a plan view of a sheet coil according to a second embodiment of the present invention.

FIG. 3A is a front sectional view of a pot core transformer and FIG. 3B is a plan view of a sheet coil, showing a third embodiment of the present invention.

FIG. 4 shows a flat coil according to a fourth embodiment of the present invention,
(A) Front view, (b) Plan view.

[Explanation of symbols]

 1 Pot Core 11 Groove 12 Inner Core 13 Outer Core 2, 2A, 2B, 2C, 2D Sheet Coil 21 Through Hole 3, 3A, 3B Pin 4 Slit 5 Substrate 51, 51A, 51B Connection Terminal 6 Lead 7 Opening 8 Core 25 Flat Plate Coil 26 coil end

Claims (5)

[Claims] 1. A core of a magnetic material, a sheet coil in which a spiral conductor foil is provided with through holes at the beginning and end thereof, and a conductor for accommodating the sheet coil in the core and inserting the through hole. In the element assembly of the transformer provided with the pin, the core has a groove in the magnetic cylindrical body, and an opening is formed in the upper portion,
It is a pot core provided with a slit penetrating from the bottom of the groove to the lower portion of the core, the sheet coil is a sheet coil punched by pressing a foil of a conductor, the surface is an insulation coating, on the bottom surface of the bottom of the pot core A connection board having a connection terminal is provided, the sheet coil is housed in the groove of the pot core, the pin is inserted through the slit, and the insertion end is connected to the connection terminal. Element assembly. 2. The transformer element assembly is composed of two sets, a primary side and a secondary side having different numbers of sheet coils, and the two sets of the transformer element assemblies are connected at the opening. Pot core transformer. 3. An element assembly of the transformer is covered at its opening side with a disk-shaped core, and the sheet coils are made up of two sets, a primary side and a secondary side, in which the positions of the through holes are displaced, and are stacked. The pot core transformer is also housed in the groove of the pot core. 4. An element assembly of the transformer is covered on its opening side with a disk-shaped core, and the sheet coil has two types, a large diameter one and a small diameter one, and an inner diameter side of the large diameter sheet coil. A pot core transformer characterized by having a small-diameter sheet coil fitted in. 5. The sheet coil is formed by spirally winding a thin conductive wire coated with insulation, and replacing the coil end at the start end and the end of the spiral with a flat plate coil bent in a direction perpendicular to the plate surface of the flat plate coil. The pot core transformer according to claim 2, wherein an end portion of the coil end is connected to the connection terminal.