JPH0662519U - Thin transformer and E-type iron core for the thin transformer - Google Patents

Abstract

(57) [Abstract] [Purpose] The lead wire of the high voltage side coil does not interfere with the winding, the number of turns is increased, and the insulation performance between the lead wire of the high voltage side coil and other coils and between the iron core is improved. . [Structure] A plurality of coils 62, 64 are wound around a body portion 70, a middle leg 98 of an E-shaped iron core 66 is fitted into a center hole 82 of the body portion 70, and a plurality of iron cores 66, 68 are joined and mounted. It consists of the bobbin 60. Then, through-holes 90 and the like into which the lead wires 106 of the high-voltage side coil 64 are inserted are provided in the terminal installation protrusions 78 of the bobbin 60 at the winding start position and the winding end position with respect to the body portion 70, and the lead wire installation to the terminals 74 is installed. The iron core 66 is not arranged at the place. Therefore, as the E-shaped iron core 66, the one provided with the middle leg 98 close to one edge of the base portion 104 connecting both outer legs is used.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a thin transformer used for an inverter circuit and the like, and an E-type iron core suitable for the thin transformer.

[0002]

[Prior art]

 2. Description of the Related Art Conventionally, in electronic devices and the like, a compact transformer in which an E-type, I-type, or the like iron core is joined and attached to a bobbin wound with a plurality of coils is used to miniaturize the device. For example, a thin transformer 10 having a sectional structure as shown in FIG. 13 is used for the inverter circuit. In the figure, 12 is a bobbin, 14 and 16 are primary and secondary coils wound around the bobbin 12, and 18 and 20 are E-type and I-type iron cores attached to the bobbin 12 and attached. The bobbin 12 has a bilaterally symmetrical plane structure as shown in FIG. 14. The bobbin 12 has a circular collar portion 24 on the upper side of the coil winding body portion 22 and further left and right sides of the collar portion 24 on the lower side. There are rectangular terminal installation protrusions 30 and 32 provided with six terminal pins 26 and 28, respectively, and a circular through hole 34 vertically penetrating the center of the body portion 22 is provided at the center. Then, the circular middle leg 36 of the E-shaped iron core 18 as shown in FIG. 15 is fitted into the center hole 34 of the bobbin 12. Incidentally, FIG. 16 is a left side view of the E-shaped iron core 18.

In such an E-shaped iron core 18, the cross-sectional area of the middle leg 36 is made equal to the cross-sectional area of both the outer legs 38, 40, and the base portion 42 connecting the both outer legs 38, 40 to make the transformer 10 thin. The thickness of the base is reduced and the width of the left and right is increased to increase the area of the base portion 42. Then, the middle leg 36 is provided at the center of the base 42. Therefore, the primary and secondary coils 14 and 16 are wound around the body portion 22 of the bobbin 12, the middle leg 36 of the E-shaped iron core 18 is fitted into the center hole 34 of the body portion 22, and the I-shaped iron core 20 When they are joined and attached, a left-right symmetric planar structure as shown in FIG. 17 is obtained, and an enlarged sectional view taken along line X-X thereof is as shown in FIG. In the figure, 44 (44a, 44b) and 46 (46a and 46b) are lead wires of the primary and secondary coils 14 and 16, and 50 and 52 are lead wires provided near the terminal pins 26 and 28. The positioning grooves of the wires 46 and 44, and 54 and 56 are insulating papers which are interposed between the primary and secondary coils 14 and 16 and cover the primary coil 14.

[0004]

[Problems to be solved by the device]

 However, in such a thin transformer 10, the lead wires 44 and 46 of the primary and secondary coils 14 and 16 are drawn out along the inner surfaces of the right and left terminal installation protrusions 32 and 30, respectively. It is put in the positioning grooves 52 and 50 near 26 and then wound around the terminal pins 28 and 26, respectively. Therefore, the lead wire 46 of the secondary coil 16, which is the high-voltage side where the bobbin 10 starts to be wound around the body portion 22, interferes with the winding of the primary and secondary coils 14 and 16, and the number of windings is reduced. Moreover, since the lead wire 46 of the secondary coil 16 on the high voltage side is in contact with the primary coil 14 or passes in the vicinity thereof, the insulation performance between the lead wire 46 of the secondary coil 16 and the primary coil 14 is low. Let's do it.

Therefore, in order to solve these problems, a slit for inserting each lead wire of the coil on the high voltage side is formed on the protruding portion for installing the terminal of the bobbin from the winding start position with respect to the body portion to the vicinity of the terminal pin, and is wound again. The ones provided from the end position to the vicinity of the terminal pins are presented. However, when the lead wire is inserted by forming a slit in the bobbin terminal installation protrusion in this way, the lead wire is now placed near the base of the iron core, so insulation performance between the lead wire and the iron core is a problem. become. In addition, in order to improve the insulation performance between the primary coil and the secondary coil, there is a bobbin divided for each coil, but the structure is complicated and the number of windings is reduced.

The present invention has been made in view of such a conventional problem, and the lead wire of the high-voltage coil does not obstruct the winding, the number of windings can be increased, and the coil of the high-voltage side can be drawn out. An object of the present invention is to provide a thin transformer having good insulation performance between a wire and another coil and an iron core, and an E-shaped iron core suitable for enhancing the insulation performance of the thin transformer.

[0007]

[Means for Solving the Problems]

 To achieve the above object, the thin transformer 58 according to the present invention has a plurality of coils 62 and 64 wound around a body 70, and at least one E-shaped iron core 66 is used in a center hole 82 of the body 70. The bobbin 60 is formed by fitting legs 98 and joining a plurality of iron cores 66 and 68 to each other. Then, through holes 90 and 92 for receiving the lead wires 106 of the high-voltage side coil 64 are provided in the terminal installation protrusion 78 of the bobbin 60 at the winding start position and the winding end position with respect to the body portion 70, respectively. The iron core 66 should not be arranged in the vicinity of each lead wire installation location from the through holes 90, 92 to the connecting terminal pin 74. Further, the E-type iron core 66 used for such a thin transformer 58 has its middle leg 98 located near one edge of the base 104 connecting both outer legs 100 and 102.

[0008]

[Action]

 With the configuration described above, one lead wire 106a of the high voltage side coil 64 is inserted into the through hole 90 provided at the winding start position for the body portion 70 and guided to the terminal pin 74, and the other lead wire 106b is finished. If the iron core 66 is not placed in the vicinity of the respective lead wire installation points from the holes 90, 92 to the terminal pin 74 to be connected, the lead wire 66 is inserted into the through hole 92 provided at Since 106 enters through holes 90 and 92 provided at the positions of the beginning of winding and the positions at the end of winding, respectively, the number of windings can be increased without hindering the winding of coils 62 and 64. In addition, since each lead wire 106 of the high-voltage coil 64 can be inserted into the through holes 90 and 92 and separated from the other coil 62, the lead wire 106 of the high-voltage coil 64 and the other coil 62 can be separated from each other. The insulation performance is improved. Further, since the iron core 66 is not arranged in the vicinity of each lead wire installation location from the through holes 90, 92 into which each lead wire 106 of the high voltage side coil 64 is inserted to the connecting terminal pin 74, the lead wire 106 of the high voltage side coil 64 is not provided. The insulation performance between the core 66 and the iron core 66 is also improved.

When the middle leg 98 of the E-shaped iron core 66 is provided near one edge of the base portion 104 connecting the outer legs 100 and 102, the base portion 104 does not exist on one side of the base of the middle leg 98. Therefore, when the middle leg 98 of the E-shaped iron core 66 is fitted into the center hole 82 of the body portion 70 of the bobbin 60, the through holes 90 and 92 for inserting the lead wires 106 of the high voltage side coil 64 are provided for terminal installation. It is easy to arrange so that the base 104 does not exist on the side of the protrusion 78.

[0010]

【Example】

 Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. 1 and 2 are views showing the structure of the main part of a thin transformer for an inverter circuit to which the present invention is applied (enlarged sectional view taken along line YY and ZZ in FIG. 11), respectively. . In the figure, 58 is a thin transformer, 60 is its bobbin, 62 and 64 are primary and secondary coils wound around the bobbin 60, and 66 and 68 are E-type and I-type attached to the bobbin 60. It is an iron core.

FIG. 3 is a plan view of the bobbin, FIG. 4 is a left side view thereof, and FIG. 5 is a bottom view thereof. This bobbin 60 also has a circular collar portion 72 on the upper side of the coil winding body portion 70, and six terminal pins 74, 76 on the lower side that further project to the left and right from the collar portion 72. There are shaped terminal installation protrusions 78 and 80, and a circular through hole 82 that vertically penetrates the center of the body 70 near the center. However, the body portion 70 and the collar portion 72 are offset to the left side, and the center of the through hole is also offset to the left side from the center of the bobbin 60. Then, the upper surface of the right side portion 84 is further lowered from the vicinity of the through hole 82 of the flange portion 72 so that the I-shaped iron core 68 is placed. Further, the bottom center portion 86 of the bobbin 60 is raised except the end portions of the left and right terminal installation protrusions 78 and 80, and the lower surface is raised further, and the right side portion 88 from the through hole 82 is connected to the base portion of the E-shaped iron core 66. Make it a place to install.

Further, a slit 90 is formed as a through hole into which one lead wire of the secondary coil 64 is inserted in the left terminal installation protrusion 78, and two slits 90 are provided at the center from the vicinity of the body portion 70 to the vicinity of the terminal pin 74. It is provided in a straight line between the terminal pins 74. Further, the left terminal installation protrusion 78 is provided with a slit 92 as a similar through hole between the two rear terminal pins 74. However, the length from the terminal pin 74 near the slit 92 is shortened. Then, the innermost portion of the slit 90 is set to the winding start position with respect to the body portion 70 of the secondary coil 64, and the innermost portion of the slit 92 is set to the winding end position. It should be noted that a lead wire positioning groove 94 is provided between the terminal pins 74 having no slits 90 and 92 on the lower surface of the left terminal placement protrusion 78 so as to communicate with the central portion 86. Further, short grooves 96 for positioning the lead wire are provided between the terminal pins 76 on the upper surface of the right terminal installation projection 80.

FIG. 6 is a plan view of the E-shaped iron core, and FIG. 7 is a left side view thereof. The E-shaped iron core 66 makes the cross-sectional area of the mid-legs of the beam to be equal to the cross-sectional area of the outer legs 100 and 102, and the thickness of the base portion 104 connecting the outer legs 100 and 102 is reduced in order to make the transformer 58 thin. The area of the base 104 is increased by reducing the width and increasing the width on the left and right. However, the middle leg 98 is provided near the left edge. Thus, when the middle leg 98 is provided near the left edge of the base 104, the base 104 does not exist on the left side of the root of the middle leg 98.

FIG. 8 is a plan view of the I-shaped iron core, and FIG. 9 is a left side view thereof. The I-shaped iron core 68 has the same shape and size as the base portion 104 of the E-shaped iron core 66. Then, the bobbin 60 is joined to the E-type iron core 66 and mounted. Instead of the I-shaped iron core, it is also possible to use an E-shaped iron core in which the middle leg is located near the right edge of the base portion connecting both outer legs.

FIG. 10 is a front view of the assembled thin transformer, FIG. 11 is its plan view, and FIG. 12 is a bottom view. At the time of assembly, first, the secondary coil 64 on the high-voltage side, which has a large number of windings, is wound around the body portion 70 of the bobbin 60. The lead wire 106a on the winding start side has the slit 90 provided on the left terminal installation protrusion 78. The lead wire 106b on the winding end side is inserted into the slit 92 and guided to the adjacent terminal pins 74 and wound. After that, the low-voltage side primary coil 62 having a small number of windings is wound around the secondary coil 64, and the lead wire 108a on the winding start side is made to follow the inner surface of the right terminal installation protrusion 80, The lead wire 108b on the winding end side is also placed along the inner surface of the groove 96 at a position corresponding to the slit 90, and then inserted into the groove 96 at a position corresponding to the slit 92, and the terminal pin 76 in the vicinity thereof is inserted. Guide and wrap each. Note that each lead wire 106 of the secondary coil 64 passes through the slits 90 and 92, respectively, and extends below the left-side terminal installation protrusion 78, and after being positioned along the lower surface, the positioning adjacent to the slits 90 and 92 is performed. It is inserted into the groove for use 94 and is led to the terminal pin 74 to be connected.

In this way, when each lead wire 106 of the secondary coil 64 is inserted into the slits 90 and 92 provided at the winding start position and the winding end position, respectively, the secondary and primary coils 64 and 62 The secondary voltage can be increased by increasing the number of windings without disturbing the winding. Moreover, since each lead wire 106 of the secondary coil 64 can be separated from the primary coil 62 by inserting it into the slits 90 and 92, insulation between each lead wire 106 of the secondary coil 64 and the primary coil 62 is achieved. Performance is improved. Even if the primary voltage is 12V, the secondary voltage is several KV.

Next, the middle leg 98 of the E-shaped iron core 66 is fitted into the center hole 82 of the body portion 70, and the I-shaped iron core 68 is joined and mounted, whereby the assembly of the thin transformer 58 is completed. At this time, if the middle leg 98 of the E-shaped iron core 66 is provided near the left edge of the base portion 104, the base portion 104 does not exist on the left side of the root of the middle leg 98, so that the protrusion 78 for installing the left terminal is formed. It can be easily placed so that there is no base 104 on the side. Therefore, the insulation performance between each lead wire 106 of the secondary coil 64 and the E-shaped iron core 66 is also improved. The insulating paper 110 is interposed between the primary and secondary coils 62 and 64, and the surface of the primary coil 62 is covered with the insulating paper 112.

[0018]

[Effect of device]

 According to the present invention described above, since the through-holes for inserting the lead wires of the high-voltage side coil are provided in the bobbin terminal installation protrusions at the winding start position and the winding end position with respect to the body, respectively, The winding of the high voltage side coil does not get in the way of the leader wire, improving workability. Moreover, since the number of windings can be increased, a high voltage can be obtained. Also, if each lead wire of the high voltage side coil is placed in the through hole and separated from the other coil, it becomes easy to obtain the required insulation performance between the lead wire of the high voltage side coil and the other coil. Furthermore, since the iron core is not arranged near each lead wire installation location from the through hole to the connecting terminal pin, the insulation performance between the lead wire of the high-voltage coil and the iron core is also improved. Therefore, since it is easy to ensure insulation, the structure of the transformer can be simplified, the thickness can be made thinner, and the cost can be reduced.

Further, when the E-shaped iron core provided by arranging the middle leg near one edge of the base part connecting both outer legs is used, the base part does not exist on one side of the root of the middle leg, so that the body part of the bobbin is If the middle leg of the E-type iron core is fitted in the center hole, it is easy to arrange so that the base does not exist on the side of the terminal installation protrusion with the through hole for inserting each lead wire of the high voltage side coil. The insulation performance can be easily improved.

[Brief description of drawings]

FIG. 1 is a diagram (enlarged sectional view taken along line YY of FIG. 11) showing a structure of a main part of a thin transformer for an inverter circuit to which the present invention is applied.

FIG. 2 is a diagram (ZZ line enlarged sectional view of FIG. 11) showing a structure of another main part of the same thin transformer.

FIG. 3 is a plan view of a bobbin used in the thin transformer.

FIG. 4 is a left side view of the bobbin.

FIG. 5 is a bottom view of the bobbin.

FIG. 6 is a plan view of an E-shaped iron core used in the thin transformer.

FIG. 7 is a left side view of the E-shaped iron core.

FIG. 8 is a plan view of an I-type iron core used in the thin transformer.

FIG. 9 is a left side view of the same type I iron core.

FIG. 10 is a front view of the thin transformer.

FIG. 11 is a plan view of the thin transformer.

FIG. 12 is a bottom view of the thin transformer.

FIG. 13 is a diagram (enlarged sectional view taken along line XX in FIG. 17) showing a structure of a main part of a conventional thin transformer.

FIG. 14 is a plan view of a bobbin used in the thin transformer.

FIG. 15 is a plan view of an E-type iron core used in the thin transformer.

FIG. 16 is a left side view of the E-shaped iron core.

FIG. 17 is a plan view of the thin transformer.

[Explanation of symbols]

58 ... Thin transformer 60 ... Bobbin 62, 64 ... First and second coils 66, 68 ... E-type, I-type iron core 70 ...
Body portion 72 ... Collar portion 74, 76 ... Terminal pin 78, 80
... Left and right terminal installation protrusions 82 ... Center hole 90,
92 ... Slit 94, 96 ... Positioning groove 98 ... Middle leg 100, 10
2 ... Outer leg 104 ... Base 106, 108 ... Leader wire

Claims (2)

[Scope of utility model registration request] 1. A bobbin in which a plurality of coils are wound around a body, and at least one middle leg of an E-shaped iron core is fitted in a center hole of the body, and a plurality of iron cores are joined and mounted. In the thin transformer, through-holes for inserting the lead wires of the high-voltage coil are provided at the bobbin terminal-installing protrusions at the winding start position and the winding end position with respect to the body, and terminals are connected through these through holes. A thin transformer characterized in that an iron core is not placed near the locations where the respective lead wires are installed. 2. The E-type iron core for a thin transformer according to claim 1, wherein the middle leg is provided close to one edge of a base portion connecting both outer legs.