JP2595157Y2 - Trance - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transformer provided on a printed circuit board.

[0002]

2. Description of the Related Art Conventionally, when a transformer is provided on a printed circuit board, the transformer is configured as shown in FIG. 8, for example. That is, in FIG.
A coil is wound around a coil bobbin 2 formed in a hollow cylindrical shape having a hollow portion 2a and having flanges 2b and 2c at both ends, in a winding groove 2d between the flanges 2b and 2c. To form the primary coil 3 and the secondary coil 4, and the winding lead terminals of the coils 3 and 4 are provided with pins 5 provided so as to extend downward from the lower flange 2 c of the coil bobbin 2.
And the core 6 is inserted and fixed in the hollow portion 2 a of the coil bobbin 2.

When mounting the transformer 1 configured as described above on a printed circuit board 7, the respective pins 5 are inserted into mounting holes 7a provided in the printed circuit board 7, and the transformer 1 is mounted by soldering or the like. It is fixed on the printed board 7 and is electrically connected to a conductive pattern or the like formed on the printed board 7.

[0004]

However, in the transformer 1 constructed as described above, the primary coil 3 and the secondary coil 4 are formed by winding the winding around the groove of the coil bobbin 2, and the coil It is necessary to tie the winding lead terminals 3 and 4 to the pins 5. For this reason, the number of components is large, the assembling work is complicated, and at the time of mounting on a printed board, a coil bobbin having pins is mounted on the printed board, so that the mounting dimensions are relatively high. There was a problem.

In view of the above, the present invention reduces the number of components, forms a thin structure, and facilitates coil wiring work by forming some coils directly on a printed circuit board. The purpose is to provide a transformer that can be used.

[0006]

According to the present invention, there is provided a core mounted on a printed circuit board in a coil area of the printed circuit board so as to face both sides of the printed circuit board. A coil made of a long flexible substrate having a conductive pattern extending in a longitudinal direction, wound around a central core portion of the core inserted into the printed circuit board, and protruding from the flexible substrate. The extended portion is electrically connected to the conductive pattern disposed on the surface of the printed circuit board by being elastically contacted with the conductive pattern.
Achieved.

According to the present invention, a core mounted on a printed circuit board and a core inserted into the printed circuit board are arranged so as to face each other from both sides of the printed circuit board in a coil area of the printed circuit board. A coil made of a long flexible substrate provided with a conductive pattern extending in a longitudinal direction, wound around a central core portion of the formed core, and a spring member attached to the flexible substrate. Is achieved by a transformer, which is electrically connected to a conductive pattern provided on the surface of a printed circuit board by elastically contacting the conductive pattern.

[0008]

According to the above arrangement, the coil can be formed by directly winding the long flexible substrate having the conductive pattern extending in the longitudinal direction around the central core portion of the core. Since the coil bobbin for the coil is not required, the number of parts is reduced, and the cost of parts and the cost of assembly can be greatly reduced.

Further, since the coil bobbin is unnecessary and the coil is wound directly on the core,
The projecting height on the printed circuit board is greatly reduced, and the entire transformer can be configured to be thin.

[0010] Furthermore, the coil winding is electrically connected to the conductive pattern formed on the surface of the printed circuit board by an extension or a spring member protruding from the flexible board constituting the coil. Can be connected to

Therefore, since the soldering work is not required, the wiring work is facilitated, the assembly can be performed easily and in a short time, and the parts cost and the assembly cost can be reduced.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the embodiments shown in the drawings. FIG. 1 shows an embodiment of a transformer according to the present invention. Coil 1
2, cores 13 and 14 attached to the printed board 11 so as to face each other from above and below the printed board 11 in the area of the coil 12, and a secondary coil 15 wound around the core 13. It is composed of

As shown in FIG. 2, the primary coil 12 includes two connection lead patterns 1 extending leftward in the drawing.
6 and 17, one side (spiral outside) end 12a
Are directly and integrally connected to one of the lead patterns 16 and the other end (spiral inner side) 12 b
Is connected to the other lead pattern 17 so as to intersect the spirally formed primary coil 12.

As shown in the drawing, the other end 12b of the primary coil 12 is connected to the lead pattern 17 via a jumper 19 which intersects an insulating layer 18 mounted on the primary coil 12 in the case shown in FIG. The end portion 1 can be connected, but is not limited thereto, for example, via a conductive pattern formed inside a multilayer printed circuit board 11.
2b may be connected to the lead pattern 17.

Of the cores 13 and 14, the core 13 is
As shown in FIG. 1, a disc-shaped main body 13a and
a central core portion 13b extending downward from the central portion of
An annular core portion 13c extending downward from a peripheral portion of the main body 13a.
Parts that are diametrically opposed to each other are cut away.

After the secondary coil 15 to be described later is wound around the center core portion 13b of the core 13 thus configured, the core 13 is moved to the center of the printed circuit board 11 including the coil 12. The core 13 b is
The annular core 13c is inserted into the insertion hole 11b, and the center core 13b and the annular core 13c projecting from the lower surface of the printed circuit board 11 are fixed to the upper surface of the core 14. I am getting it. As a result, the cores 13 and 14 are attached so as to sandwich the printed board 11.

Here, as shown in FIG. 3, the secondary coil 15 is formed of a long flexible substrate 15a and has a conductive pattern 15b extending along the longitudinal direction thereof. The conductive pattern 15b has connection terminals 15c and 15d with both ends bent in the vertical direction and protruding from the side edge of the flexible substrate 15a. Connecting such a flexible substrate 15a to the connection terminal 1
By winding such that 5c is on the inside, the secondary coil 15 can be configured as shown in FIG.

Further, the secondary coil 15 is fitted on the central core portion 13b of the core 13, and its connection terminal portions 15c and 15d are formed on the lead patterns 20 and 21 formed on the lower surface of the printed circuit board 11. It is adapted to be connected to the connection parts 20a, 21a. At this time, the connection terminal 1
As shown in FIG. 1, the flexible substrates 15 a are bent by bending the flexible substrate 15 a and the intermediate portion abuts against the inner wall of the core 14, thereby reducing the elasticity due to the flexibility of the flexible substrate 15 a itself. Based on this, the distal ends are pressed against the connection portions 20a and 21a, respectively. Thus, the connection terminal portions 15c, 15d
Can be electrically connected to the connection portions 20a and 21a, respectively.

The transformer 10 according to the present invention is configured as described above, and the core 1 on which the coil 15 is wound around the printed circuit board 11 on which the coil 12 is formed.
3 and 14 are mounted, and the connection terminal portions 15c and 15d of the coil 15 are brought into contact with the connection portions 20a and 21a of the lead patterns 20 and 21 of the printed circuit board 11, thereby completing the assembly of the transformer 10. Become.

Accordingly, the number of parts is small and no soldering work is required, so that the assembling can be easily performed.

Since the coils 12 and 15 are formed in a plane on the surface of the printed circuit board 11, the height of the coils 12 and 15 protruding above the printed circuit board 11 with the cores 13 and 14 mounted thereon. Can be significantly reduced,
Thinning can be promoted.

Further, the primary coil 12 and the secondary coil 15
Is configured as a multiple winding, so that the degree of coupling between the primary coil 12 and the secondary coil 15 can be relatively large.

FIG. 5 shows a modification of the above-described embodiment. In the embodiment of FIG. 1, the connection terminals 15c and 15d of the secondary coil 15 are
5a, the secondary coil 22 is formed by extending the conductive patterns 22b of the flexible substrate 22a in place of the connection terminals 15c and 15d. , A spring member 23 attached by soldering, welding, or the like.

In this case, the free end 23a of the spring member 23 is connected to the connecting portion 2 of the lead patterns 20 and 21 of the printed circuit board 11 based on its inherent elasticity.
0a and 21a can be elastically contacted.

Thus, both ends of the conductive pattern 22b constituting the secondary coil 22 can be electrically connected to the lead patterns 20, 21 via the spring member 23.

FIG. 6 shows another embodiment of the transformer according to the present invention. That is, in FIG.
Has the same configuration as the transformer 10 of FIG. 1 except for the secondary coil 31. Here, the secondary coil 31
Is a long flexible substrate 31a as shown in FIG.
And a conductive pattern 3 extending along its longitudinal direction.
1b. The conductive pattern 31b has both ends bent in the vertical direction and protrudes from the side edge of the flexible substrate 31a, thereby forming the connection terminal portions 31c and 31d.
Is composed.

In this case, the width of the flexible substrate 31a is slightly smaller than the height of the internal space of the cores 13 and 14, and the connection terminals 31c and 31d are
By providing notches on both sides, each has a required length.

By winding such a flexible substrate 31a such that the connection terminals 31c are on the inside,
As shown in FIG. 6, the secondary coil 31 can be configured by being incorporated in the cores 13 and 14 of the transformer 30.

According to this configuration, the secondary coil 31 has the conductive pattern 31b displaced in the vertical direction because the both sides of the flexible substrate 31a have relatively little backlash with respect to the inner walls of the cores 13 and 14. I won't. Therefore, the degree of coupling between the primary coil 12 and the secondary coil 31 can be maintained in a relatively large state.

[0030]

As described above, according to the present invention, by forming some coils directly on a printed circuit board, the number of parts is reduced and the structure is reduced.
It is possible to provide an extremely excellent transformer in which the wiring work of the coil can be easily performed.

In the above description, the terminal portion or the spring member of the secondary coil and the lead pattern (conductive pattern) may be soldered. In this case, the two are more securely connected.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a transformer according to the present invention.

FIG. 2 is a schematic cross-sectional view of the transformer of FIG.

FIG. 3 is a development view of a secondary coil in the transformer of FIG.

FIG. 4 is a schematic perspective view of the secondary coil of FIG. 3 in a state of use.

FIG. 5 is a schematic sectional view showing a modified example of the transformer of FIG.

FIG. 6 is a schematic sectional view showing another embodiment of the transformer according to the present invention.

FIG. 7 is a developed view of a secondary coil in the transformer of FIG.

FIG. 8 is a schematic sectional view showing an example of a conventional transformer.

[Explanation of symbols]

10, 30 Transformer 11 Printed circuit board 11a, 11b Insertion hole 12 Primary coil 13 Upper core 13a Central core part 14 Lower core 15, 22, 31 Secondary coil 15a, 31a Flexible board 15b, 31b Conductive pattern 15c, 31c Connection terminal part 15d , 31d Connection terminal part 16, 17 Lead pattern 18 Insulating layer 19 Jumper 20, 21 Lead pattern (conductive pattern) 20a, 21a Connection part 23 Spring member

Claims (2)

(57) [Scope of request for utility model registration] 1. A core mounted on a printed circuit board and a central core portion of the core inserted into the printed circuit board in a coil region of the printed circuit board so as to be opposed from both sides of the printed circuit board. And a coil made of a long flexible substrate provided with a conductive pattern extending along the longitudinal direction.The extended portion protruding from the flexible substrate is disposed on the surface of the printed circuit board. A transformer characterized by being electrically connected to a conductive pattern by elastically contacting the conductive pattern. 2. In a region of a coil of the printed circuit board, a core attached to the printed circuit board and a central core portion of the core inserted into the printed circuit board are opposed to each other from both sides of the printed circuit board. And a coil made of a long flexible substrate provided with a conductive pattern extending along the longitudinal direction.The coil member is mounted on a surface of the printed circuit board. Characterized by being electrically connected to the conductive pattern by elastically contacting the conductive pattern.