JP6385682B2 - Trance - Google Patents

Description

  The present invention relates to, for example, a transformer that ensures a creepage distance between a primary winding and a secondary winding that are wound adjacent to a rod provided on a bobbin.

For example, in Patent Document 1, as shown in FIG. 7, a primary winding and a secondary winding (not shown) wound adjacent to the flanges 113 a and 113 b provided on the bobbin 110, and the bobbin 110 A transformer bobbin device having a case 140 fitted from the upper side and a bottom plate 150 for closing the lower side of the case 140 is described.
In this transformer bobbin device, the protrusions 141 and 151 provided on the case 140 and the bottom plate 150 are fitted into annular recesses 117 provided between the flanges 113a and 113b, respectively.
As a result, the entire circumference of the bobbin is surrounded, and a creeping distance between the primary winding and the secondary winding can be sufficiently secured.

The creeping distance X ₁ between the primary winding and the secondary winding in the transformer bobbin device of FIG. 7 will be described in FIG. In FIG. 8, symbol Y indicates the bobbin winding axis direction.
As shown in FIG. 8, the creeping distance X ₁ is represented by the following (Equation 1).
X ₁ = A ₁ + T ₁ + D + T ₃ + D + T ₂ + A ₂ (Formula 1)
In (Equation 1) above,
A ₁ : Distance from the outer edge of the flange 113 a to the primary winding A ₂ : Distance from the outer edge of the flange 113 b to the secondary winding D: The protrusion 141 (or protrusion 151) is fitted into the recess 117. Depth T ₁ : Thickness in the winding axis direction of the flange 113 a T ₂ : Thickness in the winding axis direction of the flange 113 b T ₃ : Thickness in the winding axis direction of the protrusion 141 (or protrusion 151)

Japanese Utility Model Publication No. 61-166516

However, as shown in FIG. 9, the creepage distance X ₂ between the primary winding and the secondary winding at the portion where the lower side of the protruding portion 141 and both sides of the protruding portion 151 are abutted with each other is axially become straight path, the creeping distance X ₂ is represented by the following (equation 2).
X ₂ = A ₁ + T ₁ + T ₃ + T ₂ + A ₂ (Formula 2)
In (Equation 2) above,
A _1: distance from the outer edge of the flange 113a to the primary winding A _2: distance from the outer edge of the flange 113b to the secondary winding T _1: thickness of the winding shaft direction of the flange 113a T _2: winding axis of the flange 113b Thickness in the direction T ₃ : Thickness in the winding axis direction of the protrusion 141 (or protrusion 151)

Thus, the creeping distance X ₂ in abutting face of the projecting portion 141 and the projecting portion 151 is shorter than the creeping distance X _1.
Therefore, in the configuration as in the conventional example, there is a possibility that a sufficient creepage distance between the primary winding and the secondary winding cannot be secured.
Therefore, the extended creepage distance X ₂ in the structure as in the prior art, it is conceivable to increase the length and the length of the flange in the winding axis direction of the ridges, the transformer becomes large.

Then, an object of this invention is to provide the transformer which can lengthen the creeping distance between the primary winding and the secondary winding between the protrusion part of a case, and the protrusion part of a baseplate.
Further, the present invention provides a transformer that can increase the creepage distance between the primary winding and the secondary winding between the protrusion of the case and the protrusion of the bottom plate without increasing the size of the transformer. The purpose is to provide.

The transformer of the present invention made to achieve the above object is:
A bobbin having a flange on the outer periphery of the tubular portion;
A primary winding and a secondary winding wound adjacent to the ridge across the ridge,
A core incorporated in the tubular part;
A case having a first protrusion on the inside and covering the bobbin from above;
A bottom plate mounted on the lower side of the bobbin;
An annular recess is formed on the outer edge of the collar,
The first protrusion and the second protrusion are fitted over the entire circumference in the recess,
Both ends of the first ridge portion and both ends of the second ridge portion are overlapped when viewed from the winding axis direction of the bobbin,
The overlapped portion extends from the inside of the recess to the outside of the heel ,
The creepage distance between the primary winding and the secondary winding in the overlapped portion includes a portion fitted in the recess and a portion extending outward of the flange,
The creepage distance X _4B of the portion extending outward of the collar is the same as the creepage distance X _{4A of the} portion fitted in the recess ,
Transformer characterized by that.

In the transformer of the present invention, as a further preferable feature,
“The first protrusion and the second protrusion are overlapped with each other in the thin-walled portions provided at both ends.”
“The thickness of the overlapped portion in the winding axis direction is the same as the thickness of the other portion of the first protrusion and the second protrusion not overlapped in the winding axis direction. "
Is.

According to the present invention, the creepage distance between the primary winding and the secondary winding at both ends of the first ridge and the both ends of the second ridge does not form a linear path in the winding axis direction. In addition, it passes through the overlapping portion extending from the inside of the recess to the outside of the ridge. That is, the creepage distance between the primary winding and the secondary winding at both ends of the first protrusion and the second protrusion extends from the portion fitted in the recess (inner path) or the flange. Go through the part (outer path)
Therefore, the present invention can increase the creepage distance between the primary winding and the secondary winding.

It is a disassembled perspective view of the trans | transformer in one Embodiment of this invention. It is a principal part perspective view of the trans | transformer of FIG. 1, (a) is a protrusion of a case, (b) is a recessed part of the collar in a bobbin, (c) is a protrusion of a bottom plate. FIG. 2 is a completed view of the transformer of FIG. 1, (a) is a plan view, (b) is a cross-sectional view along arrow AA in (a), (c) is a cross-sectional view along arrow BB in (a), and (d). (A) is a CC arrow cross-sectional view of (a), (e) is a DD arrow cross-sectional view of (b), (f) is a EE arrow cross-sectional view of (b). It is an example of the creeping distance in the state which combined Fig.2 (a), (b), (c). It is another example of the creepage distance in the state which combined Fig.2 (a), (b), (c). It is another example of the creepage distance in the state which combined Fig.2 (a), (b), (c). It is a disassembled perspective view of the trans | transformer of a prior art example. In FIG. 7, it is a creeping distance between the primary winding and the secondary winding in the protruding portion of the case fitted in the recess of the collar. In FIG. 7, it is the creeping distance between the primary winding and the secondary winding in the butt | matching surface of the protrusion part of a case, and the protrusion part of a baseplate.

  Hereinafter, embodiments of the present invention will be exemplarily described based on the drawings. However, the material, shape, relative arrangement, and the like of the component parts described in this embodiment are not intended to limit the scope of the present invention to that unless otherwise specified.

  (First embodiment)

  As shown in FIGS. 1 to 6, the transformer in this embodiment includes a bobbin 10, a primary winding 21, a secondary winding 22, a case 40, and a bottom plate 50.

  The bobbin 10 is formed of an insulating resin, and has an outer rod 12 provided on both sides of the rectangular tube-shaped tubular portion 11 and an intermediate rod 13 provided between the outer rods 12. An annular recess 17 is formed on the outer edge of the intermediate collar 13 at the same depth all around. Thereby, the middle collar 13 has a structure separated into two middle collars 13a and middle collar 13b. Two cylindrical E-shaped cores (not shown) are incorporated into the cylindrical portion 11 of the bobbin 10 from both sides to form a Japanese-shaped core. The Japanese character core may be a combination of an E core and an I core.

  A terminal block 18 is provided below the outer casing 12. The terminal block 18 has a plurality of connection terminals 19 that extend downward and are planted.

The primary winding 21 is wound around the cylindrical portion 11 along the winding axis direction (Y direction in the drawing) while being adjacent to the intermediate collar 13a. Further, the secondary winding 22 is wound around the cylindrical portion 11 along the winding axis direction while being adjacent to the intermediate collar 13b.
Terminals of the primary winding 21 and the secondary winding 22 are connected to the connection terminal 19. In this example, not only the primary winding 21 and the secondary winding 22 but also the auxiliary winding may be wound around the bobbin 10.

The case 40 covers the bobbin 10 from the upper side. The case 40 is formed in a ceiling tube shape having an opening on the lower surface by an insulating resin. The first protrusion is integrally formed on the inner surface of the case 40. Specifically, the first protrusions are respectively fitted to the main body part 41 of the protrusion that fits into the upper part 17a of the annular recess 17, and the right part 17b and the left part 17c of the annular recess 17 respectively. It consists of both ends 42 of the protruding ridge.
Thickness in the winding axis direction of the ends 42 of the main body portion 41 and the ridge portion of the ridge portion has the same thickness T _3, but the lower protrusions 42 are partially thin tabular The thin portion 42a. In the present example, the thickness T ₃₁ of the thin portion 42a is half of T ₃ .

The bottom plate 50 is attached to the lower side of the bobbin 10 and is formed of an insulating resin. On the upper surface of the bottom plate 50, a main body portion 51 of the ridge portion and the both ends 52 of the ridge portion that are fitted to the lower portion 17d of the annular recess 17 as the second ridge portion are integrally provided. .
Further, the thickness T ₄ of the main body portion 51 of the ridge portion in the winding axis direction is the same as T ₃ , but both ends of the ridge portion are flat thin portions 51 a formed partially thin. . In this example, the thickness T ₄₁ of the thin portion 51a is half of T ₄ (that is, T ₃ ).

Further, the length L ₁ of the protrusion of the bottom plate 50 in the direction perpendicular to the winding axis direction (X direction in the drawing) is formed to be longer than the length L ₂ of the intermediate collar 13. That is, the protruding portion of the bottom plate 50 extends outward from the intermediate collar 13. And the center of the thin part 51a in the X direction is arranged on the left and right outer edges 14 of the middle collar as viewed from the winding axis direction (see FIG. 3 (e)).

When the bobbin 10 is attached to the case 40, the protrusion 41 is fitted into the upper portion 17a of the annular recess 17, and the protrusion 42 is fitted to the right portion 17b and the left portion 17c of the annular recess 17. The
When the bottom plate 50 is attached to the lower side of the bobbin 10, the main body portion 51 of the protruding portion of the bottom plate 50 is fitted into the lower portion 17 d of the annular recess 17.
In that case, the 1st protrusion part and the 2nd protrusion part are mutually overlapped in the thin part provided in each both ends. That is, the thin portion 42a of the ridge portion 42 and the thin portion 51a of the ridge portion 51 are arranged so as to overlap and contact each other when viewed from the winding axis direction.

Then, the thickness in the winding axis direction of the overlapped portion is the same as the thickness in the winding axis direction of the other portions where the first protrusion and the second protrusion are not overlapped. In other words, the winding axis direction of the thickness of the overlapping portion is the sum of the thickness T ₄₁ of the thickness T ₃₁ and the thin portion 51a of the thin portion 42a, the same as the thickness T ₃ of the ridge of the case. Thus, protrusions which are fitted into the annular recess 17, the winding axis direction of the thickness is in the T ₃ in all parts. Incidentally, the winding axis direction of the width of the annular recess 17 in this embodiment is substantially the same as T _3.

  The above-described overlapping portion extends from the inside of the recess 17 to the outer side of the center rod 13 when viewed from the winding axis direction, and the center of the overlapping portion in the X direction is the left and right sides of the middle shaft when viewed from the winding axis direction. (See FIG. 3 (e)).

In the transformer 1 of the present embodiment configured in this manner, creeping distance X ₃ between the definitive besides overlapping portion of the primary winding 21 and secondary winding 22 is expressed by the following equation (3) (4 reference).
X ₃ = A ₁ + T ₁ + D + T ₃ + D + T ₂ + A ₂ (Formula 3)
In (Equation 3) above,
A ₁ : Distance from the outer edge of the intermediate flange 13a to the primary winding A ₂ : Distance from the outer edge of the intermediate flange 13b to the secondary winding D: The protrusion of the case 40 (or the protrusion of the bottom plate 50) Depth fitted in the recess 17 T ₁ : Thickness in the winding axis direction of the intermediate collar 13 a T ₂ : Thickness in the winding axis direction of the intermediate collar 13 b T ₃ : The protrusion (or the bottom plate 50 of the case 40) Thickness in the winding axis direction of the protrusion) In the present invention, the creepage distance means the shortest distance between the conductive parts measured along the insulator surface.

Thus, the creeping distance X ₃ of the primary winding 21 definitive besides overlapping portion of the two windings 22 are the same as the creeping distance X ₁ of a conventional example.

Next, a description will be given creepage distance X ₄ between the primary winding 21 and secondary winding 22 in the overlapped portion of the.
For the creeping distance X _4, 2 two paths are contemplated. That is, the creeping distance X ₄ are creeping distance X _{4A (inner} path, see FIG. 5) at the upper end of the overlapping portion and, creeping distance X _4B in addition the upper end of the overlapping portion _(outer path, see FIG. 6) is.

First, the creepage distance _X4A will be described.
As shown in FIG. 5, the creepage distance X _4A is represented by the following formula (4A).
X _4A = A ₁ + T ₁ + √ (T ₄₁ ² + D ² ) + T ₃₁ + D + T ₂ + A ₂ (Formula 4A)
In the above (Formula 4A),
A ₁ : Distance from the outer edge of the intermediate collar 13a to the primary winding A ₂ : Distance from the outer edge of the intermediate collar 13b to the secondary winding D: Depth at which the thin portion 42a is fitted in the recess 17 T ₁ : winding axis direction of the center flange 13a thickness T _2: winding axis direction of the thickness T ₃₁ of the middle flange 13b: winding axis direction of the thickness of the thin portion 42a (in this example _T 3/2)
T _41: the winding axis direction of the thickness of the thin portion 51a (in this example _T 3/2)

Thus, the creeping distance X _4A of the inner path in the transformer of the present embodiment, with respect to the creeping distance X ₂ in abutting face of the projecting portion 141 and the protruding portion 151 as in the prior art, comprising the following X _4AL minutes longer. That is, since T ₄₁ + T ₃₁ = T ₃ ,
X _4AL = X _4A -X ₂
= √ (T ₄₁ ² + D ² ) + DT ₄₁ (Formula 4AL)
It becomes.
The creeping distance _{X 4A,} from the creeping distance _{X 3,} are slightly shorter form. This creeping distance X _4A is because through the thin portion 51a upper surface of the superimposed portion inclined.

Next, the creepage distance _X4B will be described.
As shown in FIG. 6, the creepage distance X _4B is represented by the following formula (4B).
X _4B = A ₁ + √ (T ₁ ² + E ² ) + T ₄₁ + √ (E ² + (T ₃₁ + T ₂ ) ² ) + A ₂ (Formula 4B)
In the above (Formula 4B),
A ₁ : Distance from the outer edge of the intermediate collar 13a to the primary winding A ₂ : Distance from the outer edge of the intermediate collar 13b to the secondary winding E: Length of the thin portion 42a protruding outward from the recess T ₁ : winding axis direction of the center flange 13a thickness T _2: winding axis direction of the thickness T ₃₁ of the middle flange 13b: winding axis direction of the thickness of the thin portion 42a (in this example _T 3/2)
T _41: the winding axis direction of the thickness of the thin portion 51a (in this example _T 3/2)

Thus, the creeping distance X _4B of the outer path of the transformer of this example, with respect to the creeping distance X ₂ in abutting face of the projecting portion 141 and the protruding portion 151 as in the prior art, comprising the following X _4BL minutes longer. That is, since T ₄₁ + T ₃₁ = T ₃ ,
X _4BL = X _4B -X ₂
= √ (T ₁ ² + E ² ) + √ (E ² + (T ₃₁ + T ₂ ) ² ) −T ₁ −T ₃₁ −T ₂ (Formula 4BL)

In the present example, the creeping distance X _4B of the outer path is made the same as the creeping distance X _4A of the inner path. That is, (Expression 4AL) = (Expression 4BL).
As a result, the creepage distance between the primary winding 22 and the secondary winding 23 at both ends 42 of the first protruding portion and both ends 52 of the second protruding portion is a portion (inside Route) or a part extended from the ridge (outer route).
If the creepage distance X _{4A of} the inner route is smaller than the creepage distance X _4B of the outer route, the inner route is the creepage distance X _{4 and} if the creepage distance X _4A of the inner route is larger than the creepage distance X _4B of the outer route, the outer route is the creepage distance _{X 4.}

Thus, the transformer 1 of the present example includes the bobbin 10 having the flange 13 on the outer periphery of the cylindrical portion 11, the primary winding 21 and the secondary winding wound adjacent to the flange 13 across the flange 13. A wire 22, a magnetic core incorporated in the tubular portion 11, a case 40 having first protrusions 41 and 42 on the inner side and covering the bobbin 10 from above, and a second protrusion 51 on the upper surface. , 52 and a bottom plate 50 mounted on the lower side of the bobbin 10.
An annular recess 17 is formed on the outer edge of the flange 13.
Moreover, the 1st protrusion part 41 and 42 and the 2nd protrusion part 51 and 52 are fitted by the recessed part 17 over the perimeter.
Further, both ends 42 of the first protrusion and both ends 52 of the second protrusion are overlapped when viewed from the winding axis direction of the bobbin 10.
Further, the overlapped portion extends from the inside of the recess 17 to the outside of the flange 13.
As a result, the overlapped portion is fitted in the recess when viewed from the winding axis direction, and is extended to the outside of the bag.
Therefore, the creepage distance between the primary winding and the secondary winding at both ends of the first protrusion and the second protrusion is not a linear path in the winding axis direction, It will pass through the overlapping part straddling the outside of the bag from the inside. That is, the creepage distance between the primary winding and the secondary winding at both ends of the first protrusion and the second protrusion extends from the portion fitted in the recess (inner path) or the flange. Go through the part (outer path)
For this reason, in this example, the creeping distance between the primary winding and the secondary winding can be increased as compared with the configuration of the conventional example.

  Moreover, since the 1st protrusion part and the 2nd protrusion part mutually overlap in the thin part provided in each both ends, this example can lengthen a creepage distance by simple structure.

In addition, the thickness in the winding axis direction of the overlapped portion is the same as the thickness in the winding axis direction of the other portions where the first protrusion and the second protrusion are not overlapped.
Therefore, in this example, the creepage distance can be increased without increasing the size of the transformer.

  Moreover, in the said embodiment, although the thin part 42a of the protruding part 41 and the thin part 51a of the protruding part 51 are arranged in contact, if the total thickness of the part overlapped in the winding-axis direction is the same, The thin portion 42a of the ridge portion 41 and the thin portion 51a of the ridge portion 51 may be arranged with a slight gap in the winding axis direction.

  Moreover, in the said embodiment, although the flat strip part is formed in the protrusion part of a case, and the protrusion part of a bottom plate, respectively, it has overlapped with each other, It is not restricted to this. The creepage distance does not have to be a straight path in the winding axis direction as in the conventional example, but may pass through a portion fitted in the recess (inner path) or a part extended from the ridge (outer path). . For example, inclined portions notched in a slope shape (not shown) may be formed on the protruding portion of the case and the protruding portion of the bottom plate, respectively, and may be superimposed on each other.

DESCRIPTION OF SYMBOLS 1 Transformer 10 Bobbin 11 Cylindrical part 12 Outer cage 13, 13a, 13b
14 Left and right outer edges of the center 17 Depression 17a Upper portion of the recess 17b Right portion of the recess 17c Left portion of the recess 17d Lower portion of the recess 18 Terminal block 19 Connection terminal 21 Primary winding 22 Secondary winding 40 Case 41, 42 Case ridge (first ridge)
42a Thin-walled portion 50 Bottom plate 51, 52 The protruding portion of the bottom plate (second protruding portion)
Protrusions of 51a distance D case 40 from the outer edge of the distance A ₂ in the flange 13b from the outer edge of the thin portion A ₁ in the flange 13a to the primary winding 21 to secondary winding 22 (or ridges of the bottom plate 50 ) Is fitted into the recess 17 L ₁ The length of the protrusion of the bottom plate L ₂ The length of the middle collar 13 T ₁ The thickness of the middle collar 13 a T ₂ The thickness of the middle collar 13 b T ₃ Thickness of the ridge T ₃₁ Thickness of the thin portion 42a T ₄ Thickness of the ridge portion of the bottom plate T ₄₁ Thickness of the thin portion 51a

Claims (3)

A bobbin having a flange on the outer periphery of the tubular portion;
A primary winding and a secondary winding wound adjacent to the ridge across the ridge,
A core incorporated in the tubular part;
A case having a first protrusion on the inside and covering the bobbin from above;
A bottom plate mounted on the lower side of the bobbin;
An annular recess is formed on the outer edge of the collar,
The first protrusion and the second protrusion are fitted over the entire circumference in the recess,
Both ends of the first ridge portion and both ends of the second ridge portion are overlapped when viewed from the winding axis direction of the bobbin,
The overlapped portion extends from the inside of the recess to the outside of the heel ,
The creepage distance between the primary winding and the secondary winding in the overlapped portion includes a portion fitted in the recess and a portion extending outward of the flange,
The creepage distance X _4B of the portion extending outward of the collar is the same as the creepage distance X _{4A of the} portion fitted in the recess ,
Transformer characterized by that. The first ridge and the second ridge are overlapped with each other in thin portions provided at both ends,
The transformer according to claim 1. The thickness in the winding axis direction of the overlapped portion is the same as the thickness in the winding axis direction of the other portions where the first protrusion and the second protrusion are not overlapped,
The transformer according to claim 2.

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