JPH0851035A - Transformer - Google Patents

Abstract

PURPOSE:To obtain a transformer in which a space and a creeping distance satisfying the safety regulations are ensured between the windings while having a structure for realizing reduction in size. CONSTITUTION:At least one of primary winding 16A, 16B and secondary winding 17A, 17B is formed of an insulating wire applied with a plurality of layers of insulating coating. A bobbin 10 comprises a main bobbin part 11, an auxiliary bobbin part 12, and an intermediate flange part 14. The primary winding 16A, 16B and the secondary winding 17A, 17B are wound about the main bobbin part 11 while being overlapped in the radial direction of the bobbin 10. A part of the primary or secondary winding 16A, 16B or 17A, 17B or other winding 18 having small number of turns is wound about the auxiliary bobbin part 12. The lead out part 16a, 16b or 17a, 17b of the primary or secondary winding 16A, 16B or 17A, 17B made of the wire applied with a plurality of layers of insulation coating is led out through the auxiliary bobbin part 12 to a terminal pin 8A, 8B and soldered H thereto at the forward end thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used, for example, in a switching power supply device, and a primary winding and a secondary winding are wound around a bobbin in a radial direction of the bobbin so as to be miniaturized. It also relates to a transformer for a high frequency power supply.

[0002]

2. Description of the Related Art A transformer for a high-frequency power source, which is intended to be miniaturized, generally has a structure in which a primary winding and a secondary winding are wound around a bobbin in a radial direction of the bobbin. In this type of transformer, it is necessary to satisfy the conditions of the electrical insulation and the space / creep distance between the primary winding and the secondary winding, which are defined in the safety standard. To ensure such safety, transformers that use light-insulated wires, such as enamel-coated wires, that have a single-layer insulation film coated on the surface of the wire, such as enamel-coated wires, have coil bobbins. A barrier tape made of, for example, epoxy resin is wound around both ends of the winding frame in the axial direction,
A coil winding layer composed of a primary winding and a secondary winding is sequentially laminated between the respective coil winding layers at a position set between the barrier tapes on both sides with an insulating tape made of, for example, a polyester film interposed therebetween. There is. In this way, each barrier tape on both sides of the coil bobbin secures a space / creep distance satisfying safety standards between the primary winding and the secondary winding, and the insulating tape electrically insulates the coil winding layers. .

In the above-mentioned transformer, since a space for providing the barrier tape is required on both sides of the coil bobbin, the shape of the coil bobbin becomes large by the installation space. For this reason, in particular, in a transformer for a high-frequency power source, which is intended to be downsized, it conflicts with the requirement. Further, since a step of providing the barrier tape on each side of the coil bobbin for each coil winding layer is required, there is a drawback that assembly workability is poor and manufacturing cost is high.

Therefore, in recent years, as shown in FIG. 10, by forming a primary winding 1a, 1b using a heavy insulated wire such as a three-layer insulated wire having three layers of insulation coating, A transformer without a tape is being devised. This transformer is composed of the primary windings 1a and 1b and the enamel-coated electric wire by the three layers of the insulating coating layers of the primary windings 1a and 1b forming the first and fourth coil winding layers, respectively. Required insulation is secured between the secondary windings 2a and 2b and between the primary windings 1a and 1b and the base winding 3. The secondary windings 2a and 2b may be formed by using three-layer insulated wires instead of the primary windings 1a and 1b. The coil winding layers are electrically insulated by the insulating tape 4. However, the insulating tape 4 may be omitted. The coil bobbin 5 constitutes a magnetic circuit, for example, an E-shaped core portion 6a and an I-shaped core portion 6
It is attached to the EI core 6 made of b.

[0005]

By the way, the primary winding 1
The connection to the primary side terminal pin 8A of the three-layer insulated wire forming the coil is made by connecting the lead-out portion from the winding end of the primary winding 1 to the terminal pin 8A through the lead-out groove 5c of the one collar portion 5a of the coil bobbin 5. This is done by guiding and soldering the tip of the lead-out portion. Therefore, the primary winding 1a,
1b, the three-layer insulating coating layer of the soldering treated portion S1 shown by the parallel horizontal lines in FIG. This three-layer insulated wire is
Lost the function to secure space and creepage distance.

Therefore, the flange portion 5a on one side where the terminal pins 8A and 8B on the primary side and the secondary side of the coil bobbin 5 are provided.
Is set to be larger than the thickness of the flange portion 5b on the other side, and the tip portion S2 of the insulating coating layer in the lead-out portion of the primary winding 1a where heat is not deteriorated and the winding end portion of the secondary winding 2a are formed. During this period, a space / creep distance D that satisfies the safety standards is secured. That is, although the above-mentioned transformer can save the labor of winding the barrier tape, the entire shape of the coil bobbin 5 cannot be downsized as compared with the case where the barrier tape is provided, and thus the transformer is used as a transformer for a high frequency power supply. Not suitable.

[0007] Therefore, an object of the present invention is to provide a transformer having a structure capable of ensuring a space and a creepage distance satisfying safety standards between windings and achieving miniaturization.

[0008]

According to the present invention, in order to achieve the above-mentioned object, at least one of a primary winding and a secondary winding is formed of a heavy insulated electric wire coated with a plurality of layers of insulation coating. In a transformer in which the primary winding and the secondary winding are wound around the bobbin attached to the core in the radial direction of the bobbin, the main bobbin portion and the auxiliary bobbin portion have an intermediate brim portion on the bobbin. A lead-out portion for interposing a winding made of the heavy-insulated electric wire, which is arranged in parallel in the axial direction of the bobbin via the intermediate winding portion, is connected to the terminal pin through the auxiliary winding frame portion by soldering, and the main winding frame portion is provided. The primary winding and the secondary winding are wound on,
Of the windings, a part of the windings made of a heavy insulated wire connected to the terminal pin or another winding is wound around the auxiliary winding frame portion.

[0009] In a preferred embodiment of the present invention, the intermediate flange portion is inserted from the end portion thereof toward the bottom portion, and the primary winding or the secondary winding portion is transferred from the main winding frame portion to the auxiliary winding frame portion. An insertion groove is formed to pass through. Instead of this insertion groove, a lead-out groove may be formed that extends from the bottom portion of the intermediate flange portion toward the end portion while being inclined in the axial direction.

In another preferred embodiment of the invention,
Terminal pins for the primary winding and the secondary winding are respectively disposed on the flange portion of the auxiliary winding frame portion on the first and second side portions of the bobbin that face each other in the radial direction. , The leg portion of the terminal pin inserted into the wiring board is a so-called vertical transformer extending in the axial direction of the bobbin,
Third and fourth members that face each other in the radial direction on the intermediate collar portion.
The insertion groove is formed in at least one of the side portions of the. In this embodiment, further, one of the primary winding and the secondary winding is made of the heavy insulated electric wire, and the other is made of a light insulated electric wire having a single-layer insulating film, and the one of the windings is inserted in the insertion groove. The wire may be passed through, and a second insertion groove for passing the other winding may be formed on a side portion of the intermediate flange portion where the terminal pin for the other winding is disposed.

In still another preferred embodiment of the present invention, each of the brim portion of the main bobbin portion and the brim portion of the auxiliary bobbin portion is located on the first side portion of the bobbin,
A so-called horizontal transformer in which terminal pins for the primary winding and the secondary winding are arranged, and a second side portion that faces the first side portion in the radial direction is provided on the intermediate flange portion. The insertion groove is formed on at least one side portion of the third and fourth side portions that face each other in the radial direction.

[0012]

FUNCTION AND EFFECT All or most of the primary winding and the secondary winding are wound around the main bobbin of the bobbin in the radial direction of the bobbin. At least one of the primary winding and the secondary winding is formed of a heavy insulated wire provided with a plurality of insulating coating layers. On the other hand, the auxiliary winding part is individually wound with other windings having a small number of turns such as a base winding in a transformer for a switching power supply device, or a part of the winding consisting of a heavy insulated wire is mainly wound. It is continuously wound from the frame.

Further, in this transformer, at least one of the primary winding and the secondary winding is formed of a heavy insulated wire such as a three-layer insulated wire having a plurality of layers, for example, three layers of insulation coating. The three insulating coating layers ensure a sufficient space and creepage distance between the coil winding layers of the primary winding and the secondary winding. The lead-out portion of the heavy insulated wire is connected to the terminal pin by soldering through the auxiliary winding frame portion.

Therefore, the drawn-out portion of this heavy insulated wire necessarily has a length longer than the width of the auxiliary winding frame portion. Therefore, even if the insulating coating layer in the vicinity of the soldered portion of the insulated wire deteriorates due to heat deterioration and the insulation property deteriorates, the leading end portion of the insulated wire lead-out portion that is not thermally deteriorated is The space / creeping distance to the winding end of the other winding is a length along the inner surface of the auxiliary winding frame portion, which can sufficiently secure the safety standard. That is, since the transformer of the present invention secures the necessary space and creepage distance by utilizing the auxiliary bobbin portion of the bobbin used for the original purpose of winding the winding, the bobbin shape can be compared with the conventional one. Therefore, it can be miniaturized, and is suitable for a high frequency power supply.

According to a preferred embodiment of the present invention, the primary winding or the secondary winding is smoothly moved from the main winding frame portion to the auxiliary winding frame portion through the insertion groove or the drawing groove formed in the intermediate collar portion. Can be introduced.

According to another preferred embodiment of the present invention, the brim portion of the auxiliary winding frame portion is provided with terminal pins located on first and second side portions of the bobbin which are opposed to each other in a radial direction. In the vertical transformer, since the insertion groove is formed in at least one of the third and fourth side portions that face each other in the radial direction, the intermediate flange portion is formed of a heavy insulated wire. One of the windings wraps around the bobbin from the third or fourth side to the first or second side through the insertion groove and is then connected to the terminal pin by soldering. Therefore, the space / creeping distance from the tip of the heavy insulated wire connected to the terminal pin, which is not thermally deteriorated, to the other winding is further increased. When one winding made of the heavy insulated wire is passed through the insertion groove and the other winding made of the light insulated wire is passed through the second insertion groove, both windings are inserted in the same insertion groove. Unlike the case of passing through, no wire cross-linking occurs, so that the drawing and soldering work become easy.

According to still another preferred embodiment of the present invention, in a horizontal transformer, a second side portion, a third side portion or a third side portion opposite to the first side portion on which the terminal pin is arranged is provided. Since the insertion groove is formed in the side portion of the bobbin, one of the windings made of the heavy insulated wire passes through the insertion groove and extends from the second, third or fourth side portion of the bobbin to the first side. After wrapping around, it is connected to the terminal pins by soldering. Therefore, the space and the creepage distance from the tip of the heavy insulated wire connected to the terminal pin, which is not thermally deteriorated, to the other winding are further increased.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. 1 is a vertical sectional view showing a vertical transformer according to a first embodiment of the present invention, and FIG. 2 is a perspective view showing the bobbin. In these figures, bobbin 10
The main winding frame 11, the auxiliary winding frame 12 having a shorter axial length than the main winding frame 11, and the insertion hole 13 of the core 6 are integrally formed. The intermediate flange portion 14 interposed between the main winding frame portion 11 and the auxiliary winding frame portion 12 has first and second side portions F1 and F1 that face each other in the radial direction of the bobbin 10.
A plurality of first and second through-grooves 14a, 14 located at each of the two and entering from the end toward the bottom.
b is formed. The flange portion 15 of the auxiliary winding frame portion 12 is also formed with a plurality of lead-out grooves 15a located at the first and second side portions F1 and F2, respectively, and the lead-out groove 15a in the flange portion 15 is formed. A plurality of lead-out grooves 15b are formed on the end faces of the two side portions where the groove is formed.

Further, the flange portion 15 of the auxiliary reel 12 is provided with the required number of primary side and secondary side terminal pins 8A, 8B located on the first and second side portions F1, F2. The protruding leg portions are arranged by insert molding with the leg portions oriented in the axial direction of the bobbin 10. The legs of the terminal pins 8 are inserted into the wiring board 50. As a result, the core 6 becomes vertical to the wiring board 50 (vertical transformer).

FIG. 1 illustrates a vertical transformer for a switching power supply device. On the main bobbin 11 of the bobbin 10, most of the primary windings 16A and 16B and the secondary winding 17 are provided.
All of A and 17B are overlapped and wound in the radial direction of the bobbin 10, and the auxiliary winding frame portion 12 of the bobbin 10 is
A base winding 18 (a kind of other winding) for driving the switching element and a part of each of the primary windings 16A and 16B are wound in a radial direction of the bobbin 10. These primary windings 1
The 6A, 16B, the secondary windings 17A, 17B, and the base winding 18 are magnetically coupled via the core 6, as shown in FIG.

Primary windings 16A, 16B forming the first and fourth coil winding layers of the main winding frame 11 and the base forming the first coil winding layer of the auxiliary winding frame 12 of FIG. The windings 18 are each formed of a heavy insulated wire such as a three-layer insulated wire. The above-mentioned three-layer insulated wire has, for example, a modified polyester as the lower two layers and a polyamide as the upper one layer coated on the surface of the electrical wire. Secondary windings 17A and 17B forming the second and third coil winding layers of the main winding frame 11
Is made of light insulated wire such as ordinary enamel coated wire. On the other hand, the adjacent coil winding layers are electrically insulated by the existing insulating tape 4. This insulating tape 4 is used for each winding 16A, 16B, 17A, 17
For B and 18, while preventing the winding disorder,
Mechanical protection is provided against the force applied radially inward of the bobbin 10.

The primary windings 16A and 16B are the auxiliary winding frame 1
After being continuously wound around the main winding frame part 11 through the first insertion groove 14a from 2, the linearly returning to the auxiliary winding frame part 12 along the axial direction. The primary side terminal pin 8A in which the lead-out portions 16a and 16b from the winding ends in the auxiliary winding frame portion 12 are located in the first side portion F1 via the lead-out groove 15a.
As shown in FIG. 4, the tip end portion is wound around the terminal pin 8A, and then the solder H
It is connected to this terminal pin 8A by attachment. on the other hand,
In the secondary windings 17A and 17B of FIG. 1, the lead-out portions 17a and 17b from the winding ends of the main winding frame portion 11 are inserted through the second insertion groove 14b, the auxiliary winding frame portion 12 and the lead-out groove 15a. After being pulled out to the secondary side terminal pin 8B located on the second side portion F2 (left side in FIG. 1), it is connected to this terminal pin 8 by soldering H as in the case shown in FIG. ing. Here, since the primary windings 16A and 16B are heavy insulated wires and have high insulation properties, it is necessary to set a large insulation distance between the lead-out portions 17a and 17b of the secondary windings 17A and 17B and the primary windings 16A and 16B. Absent. Further, in the base winding 18, the lead-out portion 18a from the winding end of the auxiliary winding frame portion 12 is connected to the primary side terminal pin 8A through the lead-out groove 15a.
After being pulled out, it is connected to this terminal pin 8A by soldering H.

In the transformer of this embodiment, the primary windings 16A and 16B and the secondary winding 17 which are adjacent to each other by three layers of insulating coating layers of the primary windings 16A and 16B made of heavy insulated wires.
The space and creepage distance between the coil winding layers by A and 17B are sufficiently secured. Further, if both the primary windings 16A and 16B and the secondary windings 17A and 17B are formed of heavy insulated wires, the magnetic coupling between the two windings is weakened, and the desired transformer performance cannot be obtained. On the other hand, in this embodiment,
Since the heavy insulated wire is used only for the primary windings 16A, 16B, both the primary and secondary windings 16A, 16B, 17
A high magnetic coupling is obtained between A and 17B, and the desired performance of the transformer is maintained.

Primary windings 16A, 16 made of heavy insulated wires
At the end of B, the portion of the insulating coating layer indicated by the parallel horizontal line S1 in FIG.
Lead-out portions 16a and 16b of the primary windings 16A and 16B
The space / creep distance D1 from the tip portion S2 not thermally deteriorated to the winding end portion (lower end portion in FIG. 1) of the main winding frame portion 11 of the adjacent secondary windings 17A and 17B is equal to the auxiliary winding frame portion 12 The length is along the axial direction of, and is sufficiently long as specified in the safety standard.

That is, the transformer has a main winding frame portion 11
By winding a part of one of the primary windings 16A, 16B or the secondary windings 17A, 17B, which are wound on top of each other, formed of a heavy insulated wire around the auxiliary winding part 12, A part of the primary windings 16A and 16B in 10 and the auxiliary winding portion 12 for winding the base winding 18 are used to secure a required space / creep distance D1 defined in the safety standard. . On the other hand, in the bobbin 5 of the conventional transformer shown in FIG. 10, the required space / creep distance D is secured by forming the collar portion 5a having a large thickness, which is unrelated to the winding of the winding wire which is the original purpose. . Therefore, as is clear from the comparison between FIG. 1 and FIG. 10, the bobbin 10 of the transformer of the first embodiment has a vertical direction (axial direction) and a vertical direction (axial direction) when set to wind the same number of windings as in FIG. The size in the left-right direction (radial direction) is smaller than that of the bobbin 5 shown in FIG. 10, and it is suitable as a transformer for a high-frequency power supply that requires miniaturization.

FIG. 5 is a vertical sectional view showing a transformer according to the second embodiment of the present invention, and FIG. 6 is a perspective view showing the bobbin 10. In this embodiment, instead of the insertion grooves 14a and 14b of the first embodiment, in the intermediate flange portion 14 of the bobbin 10 of FIG. 6, from the bottom of the main winding frame 11 side to the end of the auxiliary winding frame 12 side. Tapered first and second draw-out grooves 14c and 14d extending toward the axial direction are formed, and other shapes of the bobbin 10 are similar to those of the first embodiment.

Further, as shown in FIG. 5, the main winding frame portion 11 has all the numbers of turns of each of the primary windings 16A and 16B made of heavy insulated wires and the secondary windings 17A, 17B made of light insulated wires. A bobbin is wound in the radial direction of 10.
Only the base winding 18 is individually wound on the auxiliary winding frame 12. The lead-out portions 16a and 16b from the respective winding ends in the main winding frame portion 12 of the primary windings 16A and 16B are guided to the ends of the intermediate flange portion 14 along the lead-out grooves 14c and 14d, and the intermediate flange portion 14 is formed. Is pulled out to the terminal pin 8A on the primary side so as to bridge the lead-out groove 15b of the flange portion 15 of the auxiliary winding frame portion 12, and the tip end portion is wound around this terminal pin 8A and soldered to the terminal pin 8A. It is connected to the. Secondary winding 17A, 17
B is also drawn out in the same manner as the primary windings 16A and 16B, and the tips of the drawn-out portions 17a and 17b are connected to the secondary side terminal pins 8B. Further, the base winding 18 is
The lead-out portion 18a from the winding end of the auxiliary winding frame portion 12 is pulled out to the primary-side terminal pin 8A through the lead-out groove 15a, and then connected to the terminal pin 8A by soldering H.

The transformer of this embodiment is different from that of the first embodiment in that all of the primary windings 16A and 16B made of insulated wires are wound around the main winding frame 11, but the primary windings 16A and 16B Since the lead-out parts 16a and 16b from the winding end of the main winding frame 11 of 16B pass through the auxiliary winding part 12 and are connected to the terminal pin 8A on the primary side, the heat generated in the lead-out parts 16a and 16b is reduced. A space from the undegraded tip portion S2 to the winding end portion (lower end portion in FIG. 5) in the main winding frame portion 11 of the adjacent secondary windings 17A and 17B.
The creepage distance D2 is the same as in the first embodiment.
The length is along the axial direction of, and is sufficiently long as specified in the safety standard. In particular, in this embodiment, since all the primary windings 16A and 16B are wound inside the main winding frame part 11 together with the secondary windings 17A and 17B, there is an advantage that the winding process can be simplified.

FIG. 7 is a vertical sectional view showing a horizontal transformer according to the third embodiment of the present invention. Bobbin 1 of this transformer
The overall shape of 0 is almost the same as that of the bobbin 10 of the first embodiment, but the auxiliary winding frame portion 12 is also provided on the collar portion 19 of the main winding frame portion 11.
A drawing groove 19a similar to the drawing groove 15a (FIG. 2) of the collar portion 15 is formed. In addition, on one end surface of each of the brim portion 19 of the main bobbin portion 11 and the brim portion 15 of the auxiliary bobbin portion 12, the first side portion F1 of the bobbin 10 is located, and the required number of primary and secondary sides are located. The terminal pins 8A, 8B on the side are arranged with their legs directed in the radial direction of the bobbin 10. As a result, the core 6 becomes parallel to the wiring board 50 (horizontal transformer).

Primary windings 16A, 16 composed of heavy insulated wires
A large part of B is wound around the main winding frame 11, and then the remaining part is continuously wound around the auxiliary winding frame 12 through the insertion groove 14a. Draw-out portions 16a, 16 from the winding ends in the auxiliary frame portion 12B of the primary windings 16A, 16B
b is guided to the terminal pin 8A on the primary side (left side in FIG. 7) via the lead-out groove 15a, and the tip end is connected to the terminal pin 8A on the primary side by soldering H. The secondary windings 17A and 17B made of light insulated wires are wound in the main winding frame part 11 with all the numbers of turns, and the drawn-out parts 17a, 1 from the winding ends.
7b is a secondary side (right side in FIG. 7) through the drawing groove 19a.
Is guided to the terminal pin 8B, and the tip end is connected to the terminal pin 8 by soldering H. The base winding 18 is individually wound in the auxiliary winding frame portion 12, and is drawn out from the winding end portion 18a.
Is connected to the terminal pin 8A on the primary side by soldering H via the lead-out groove 15a.

Therefore, the transformer of this embodiment is mainly different from the first embodiment only in the mounting form of the terminal pins 8A and 8B.
This is almost the same as the embodiment, and the primary windings 16A and 16B and the secondary windings 17A and 17 are to be provided with a predetermined space and creepage distance.
The space / creeping distance D3 with B is sufficiently long as specified in the safety standard.

FIG. 8 shows a vertical transformer according to the fourth embodiment. In the same figure, the first insertion groove 14a located at each of the third and fourth side portions F3, F4 of the bobbin 10 is formed at two locations on the intermediate flange portion 14, and the second insertion portion is formed at one location. A second insertion groove 14b located on the side portion F2 is formed. As shown by the solid line, the primary winding 16 made of a heavy insulated wire has one lead-out portion 16a soldered to the primary-side terminal pin 8A on the first side portion F1, and from this terminal pin 8A to the flange portion 15A. Drawout groove 15a
After being wound around the auxiliary winding frame part 12 through the first winding groove 14a in the third side part F3, the auxiliary winding frame part 12 is wound around the main winding frame part 11. The primary winding 16 then passes through the first insertion groove 14a in the fourth side portion F4, the auxiliary winding frame portion 12, the other lead-out groove 15a, and the other lead-out portion 16
b is soldered to another primary terminal pin 8A.

On the other hand, the secondary winding 17 made of light insulated wire
As shown by the alternate long and short dash line, one lead portion 17a is soldered to the secondary-side terminal pin 8B on the second side portion F2, and the lead-out groove 15a of the collar portion 15 is formed from this terminal pin 8B.
After passing through the auxiliary winding frame portion 12 through it, it is wound on the main winding frame portion 11 through the second insertion groove 14b in the second side portion F2. Then, the secondary winding 17 passes through the second insertion groove 14b again and the auxiliary winding frame portion 12, and the other lead-out portion 17b is soldered to the other terminal pin 8B on the secondary side.

Although not shown, the base winding is wound around the auxiliary winding frame portion 12, and the lead-out portions at both ends thereof are passed through the lead-out groove 15a of the flange portion 15 and soldered to the terminal pin 8A on the primary side. .

According to the fourth embodiment of FIG. 8, the intermediate collar portion 1
Since the first insertion groove 14a located at the third and fourth side portions F3 and F4 of the fourth winding 4 is formed, the primary winding 16 wound around the main winding frame portion 11 has the first insertion groove 14a. Through the third or fourth side portion F3, F4 to the first or second side portion, and then soldered to the primary side terminal pin 8A on the first side portion. . Therefore, in the space / creeping distance D4 in this case, the secondary winding 17 wound around the main winding frame 11 is exposed from the tips of the lead-out portions 16a and 16b connected to the terminal pins 8A, which are not thermally deteriorated. First
To the insertion groove 14a. This space / creeping distance D4 is the distance D1 to D in the first to third embodiments.
Compared with 3, when the axial length of the auxiliary winding frame portion 12 is the same, the first side portion F1 to the third or fourth side portion F1.
3, it will be much longer as it goes around F4. As a result, the safety standard can be more sufficiently secured.

Further, the primary winding 16 is connected to the first insertion groove 14a.
Since the secondary winding 17 is passed through the second insertion groove, unlike the case where both windings 16 and 17 are passed through a single insertion groove, a cross-link state does not occur. Work becomes easy. However, the second insertion groove 14b
By omitting this, it is possible to pass both windings 16 and 17 through the first insertion groove 14a. In addition, the first insertion groove 14a is 1
As an example, it may be provided only on the third or fourth side portions F3, F4.

FIG. 9 shows a horizontal transformer according to the fifth embodiment. In FIG. 9, the terminal pins 8A and the flange portions 15 and 19 of the main winding frame portion 11 and the auxiliary winding frame portion 12 are respectively attached.
8B is provided at the first side portion F1. The intermediate brim portion 14 is located on each of the second side portion F2, the third side portion F3, and the third side portion F3 that are radially opposite to the first side portion F1, and has a total of three insertion portions. The groove 14a is formed.

As shown by the solid line, the primary winding 16 made of a heavy insulated wire has one lead-out portion 16a which is the auxiliary winding frame portion 12.
After being soldered to the primary side terminal pin 8A provided on the collar portion 15 and wound from the terminal pin 8A to the auxiliary winding frame portion 12 through the lead-out groove 15a of the collar portion 15, the second side portion It is wound around the main winding frame part 11 through the insertion groove 14a in F2. Subsequently, the insertion groove 14a on the third side portion F3
, The auxiliary winding frame portion 12, the lead groove 15a, and the other lead portion 16b is soldered to the primary-side terminal pin 8A. Primary winding 16 wound around the main winding frame 11
Although not shown, the intermediate portion thereof passes through the insertion groove 14a and the auxiliary winding frame portion 12 in the fourth side portion F4 and is soldered to another primary side terminal pin 8A to form an intermediate tap (Fig. 3) is formed.

On the other hand, the secondary winding 17 made of light insulated wire
As shown by the alternate long and short dash line, one lead portion 17a is soldered to the secondary side terminal pin 8B provided on the collar portion 19 of the main winding frame portion 12, and the terminal pin 8B to the collar portion 19 is soldered.
It is wound around the main winding frame portion 11 through the drawing groove 19a. The other lead-out portion 17b of the secondary winding 17 is provided in another lead-out groove 1
It is soldered to another terminal pin 8B through 9a.

According to the fifth embodiment, the terminal pins 8A,
Since the insertion groove 14a is formed in the second side portion, the third side portion, and the fourth side portion opposite to the first side portion F1 in which 8B is arranged, Winding 16
After wrapping around from the second, third, or fourth side portion to the first side portion through the insertion groove 14a, it is connected to the terminal pin 8A by soldering. Therefore, in this case, the space / creeping distance D5 is equal to the lead-out portion 16a connected to the terminal pin 8A,
Of the three insertion grooves 14a in which the secondary winding 17 wound on the main winding frame 11 is exposed from the terminal pin 8A to which the lead-out portion 16b is connected, the terminal pin of which is not thermally deteriorated in 16b. 8A closest to, eg, the third side F
3 is the distance to the insertion groove 14a. This space / creeping distance D5 is the distance D in the first to third embodiments.
1 to D3, when the axial length of the auxiliary reel part 12 is the same, the first side part F1 to the third side parts F3, F3
As it goes around 4, it will be significantly longer.

Further, since the three insertion grooves 14a are provided, unlike the case where all insertion portions of the secondary winding 16 are passed through a single insertion groove, a cross-linking state does not occur, so that the drawing and soldering work can be performed. It will be easier. However, the insertion groove 1
4a may be a single unit, in which case the terminal pins 8A, 8
It is preferable to provide only the insertion groove 14a on the second side portion farthest from the first side portion F1 on which the B is provided, which allows a longer space / creep distance.

In each of the above-described embodiments, the case where the primary winding is formed of a heavy insulated wire is shown, but the secondary winding is formed of a heavy insulated wire and the primary winding and the base winding are lightly insulated. You may form with an electric wire. In this case, the place where each winding is wound is changed. For example, the secondary winding is formed of heavy insulated wire, and most of the number of turns of this secondary winding is wound on the main bobbin part, and the remaining number of turns is wound on the auxiliary bobbin part, and the primary winding and the base are wound. Each of the windings may be formed of a light insulated electric wire, and all of the windings may be wound around the main winding frame portion. Further, the base winding may be formed of a light insulated wire, and may be wound around the auxiliary winding frame portion individually or overlapping a part of the primary winding or the secondary winding.

The point is that at least most of the number of turns of the primary winding and the secondary winding is wound on the main winding frame part, and
Of the secondary winding, the lead-out portion for connection of the winding consisting of heavy insulated wire passes through the auxiliary winding frame portion and is connected to the terminal pin, or is partially wound around the auxiliary winding frame portion and the terminal If it has a structure that is connected to a pin, the space and creepage distance specified in the safety standard can be secured.

Further, all of the primary winding, the secondary winding and the base winding may be formed of heavy insulated wires.

Further, in the vertical transformer shown in FIGS. 1, 4 and 8, from the side surface of the flange portion 15 facing the bobbin radial direction, as shown by the broken line in FIG.
Type arranged so as to extend in the radial direction of 0, or
There is a type in which the terminal pin 81 extends in the radial direction of the bobbin 10 from the side surface, is bent midway, and the tip end portion thereof extends in the axial direction to be a leg portion that is inserted into the wiring board 50.
In the horizontal transformers shown in FIGS. 7 and 9, the terminal pins 82 extend in the axial direction of the bobbin 10 from the side surfaces in the axial direction of both the flange portions 15 and 19 as shown by the broken lines in FIG. Or a leg portion in which the terminal pin 83 extends from the side surface in the axial direction of the bobbin 10 and is bent midway, and the tip end portion extends in the radial direction and is inserted into the wiring board 50. There are types. The present invention is applicable to any of these types.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing a transformer according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a bobbin in the embodiment.

FIG. 3 is a circuit diagram showing wiring of the same transformer.

FIG. 4 is an enlarged front view showing a main part of the above embodiment.

FIG. 5 is a vertical sectional view showing a transformer according to a second embodiment of the present invention.

FIG. 6 is a perspective view showing a bobbin in the embodiment.

FIG. 7 is a vertical sectional view showing a transformer according to a third embodiment of the present invention.

FIG. 8 is a perspective view showing a bobbin of a transformer according to a fourth embodiment of the present invention.

FIG. 9 is a perspective view showing a bobbin of a transformer according to a fifth embodiment of the present invention.

FIG. 10 is a vertical sectional view showing a conventional transformer.

[Explanation of symbols]

6 ... Core, 8A, 8B ... Terminal pin, 10 ... Bobbin, 11
... main reel part, 12 ... auxiliary reel part, 14 ... intermediate brim part, 1
5 ... Collar portion on the side of the auxiliary reel, 19 ... Collar portion on the side of the main reel,
16, 16A, 16B ... Primary winding, 16a, 16b ... Primary winding extraction portion, 17, 17A, 17B ... Secondary winding,
17a, 17b ... Lead-out portion of secondary winding, 18 ... Base winding (other winding), F1 ... First side portion, F2 ... Second side portion, F3 ... Third side portion, F4 ... Fourth side.

Claims (8)

[Claims] 1. At least one of the primary winding and the secondary winding is formed of a heavy insulated wire having a plurality of layers of insulation coating,
In a transformer in which the primary winding and the secondary winding are wound around the bobbin attached to the core in the radial direction of the bobbin, the main bobbin portion and the auxiliary bobbin portion have an intermediate brim portion on the bobbin. The winding wire is connected in parallel to the axial direction of the bobbin, and the lead-out portion for connecting the winding made of the insulated wire is connected to the terminal pin by soldering through the auxiliary winding frame portion. While the primary winding and the secondary winding are wound, in the auxiliary winding part, a part of the winding formed of a heavy insulated wire connected to the terminal pin, or another winding, of each of the windings. A wound transformer. 2. The method according to claim 1, wherein the intermediate brim is
A transformer having an insertion groove that is inserted from an end portion thereof toward a bottom portion to pass the primary winding or the secondary winding from the main winding frame portion to the auxiliary winding frame portion. 3. The intermediate brim portion according to claim 1,
A transformer having a lead-out groove extending from the bottom toward the end in the axial direction and passing the primary winding or the secondary winding from the main winding frame portion to the auxiliary winding frame portion. 4. The primary winding and the secondary winding according to claim 2, wherein the flange portion of the auxiliary winding frame portion is located at first and second side portions of the bobbin which are opposed to each other in the radial direction. A transformer in which a terminal pin for winding is disposed, and the insertion groove is formed in the intermediate flange portion at at least one of third and fourth side portions facing each other in the radial direction. 5. The method according to claim 4, wherein the other of the primary winding and the secondary winding is a light insulated wire having a single-layer insulating film, and the one winding is passed through the insertion groove. A transformer having a second insertion groove through which the other winding is inserted, on a side portion of the intermediate flange portion where the terminal pin for the other winding is disposed. 6. The primary winding and the secondary winding according to claim 2, wherein the collar portion of the main bobbin portion and the collar portion of the auxiliary bobbin portion are respectively located on a first side portion of the bobbin. A terminal pin for winding is disposed, a second side portion that faces the first side portion in the radial direction, and a third side and a fourth side that face each other in the radial direction, in the intermediate collar portion. A transformer having the insertion groove formed on at least one of the side portions. 7. The transformer according to claim 1, wherein the primary winding is formed of a heavy insulated wire, and the primary winding is wound around the auxiliary winding frame portion. 8. The auxiliary winding frame portion according to claim 1,
A transformer in which the other winding formed of a heavy insulated wire is wound.