JP6569351B2 - Insulated transformer mounting board and power supply - Google Patents

Description

  The present invention relates to an insulating transformer mounting board in which an insulating transformer is mounted on a component mounting surface of the board, and a power supply device including the insulating transformer mounting board.

  For example, the following patent document discloses an invention of a small transformer (hereinafter also simply referred to as “transformer”) that is mounted on a substrate and constitutes a power supply circuit. This transformer uses a bobbin provided with hooks at both ends (upper end and lower end) of the cylindrical winding part, and a wire is wound around the cylindrical winding part of the bobbin so that the primary coil and the secondary coil are wound. Each of the next coils is formed. In addition, terminal pins for connecting both the wire materials of the primary coil and the secondary coil to the wiring pattern of the mounting board are respectively planted on the lower end of the bobbin. Further, in this transformer, an E-shaped ferrite core (magnetic core) is mounted so as to sandwich a bobbin in which a primary coil and a secondary coil are formed, and a magnetic path is formed around both coils.

  In this case, in this type of transformer, since it is necessary to sufficiently insulate the primary coil and the secondary coil, both coils are formed using a wire with a high insulation coating. However, even if a wire with a high insulation coating is used, the portion of the wire that has been removed to connect to the connection pin (the end of the wire on the connection pin side) or the connection pin to which the wire is connected The insulation is not maintained. Therefore, in this transformer, the primary coil and the secondary coil are formed by winding the wire only on the portion near the center portion in the tube length direction (the portion away from the flange) in the tube winding portion, thereby forming the tube A barrier space in which no coil exists is provided in a portion of the winding portion near both ends in the tube length direction (a portion close to the flange: a portion close to the terminal pin).

  Thereby, in this transformer, between the connection pin and the secondary coil (wire material for the secondary coil wound around the cylindrical winding part), which is implanted in the lower cage and connected to the primary coil. Insulation and insulation between the primary coil (wire material for the primary coil wound around the cylindrical winding) and the connection pin that is planted in the lower cage and connected to the secondary coil are secured. Has been.

JP-A-7-240324 (page 3-4, FIG. 1-6)

  However, the transformer disclosed in the above patent document has the following problems. That is, in a conventional transformer, a barrier space is provided in a portion near both ends of the cylindrical winding portion in the cylindrical length direction, so that the coil (wire) wound around the cylindrical winding portion and the rod are implanted. A configuration that ensures insulation between the terminal pins is employed. In this case, since the diameter of the wire with high insulation coating increases by the thickness of the coating, a large bobbin is required when the number of turns necessary for forming the coil is large. For this reason, when both a primary coil and a secondary coil are comprised with the wire with which high insulation coating was given, size reduction of a transformer becomes difficult.

  Therefore, the applicant configured either one of the primary coil and the secondary coil with a wire with a coating having a sufficiently high insulation, and the other coil with a wire with a simple coating. Prototype transformer. Specifically, while using the same bobbin and magnetic core as the transformer bobbin and magnetic core disclosed in the above patent document, as an example, a secondary coil with a small number of turns is provided with a highly insulating coating. About the primary coil comprised with a wire and many windings, it comprised with the wire with which simple coating | cover was given. By adopting such a configuration, the wire can be wound around the cylindrical winding portion over a sufficient number of turns without impairing the insulation between the coils or causing an increase in the size of the bobbin. It was confirmed that it was possible.

  On the other hand, in the transformer prototyped by the applicant, the magnetic core exists in the vicinity of the primary coil (primary winding) composed of a wire with a simple coating, so the secondary coil (secondary winding) It is preferable to ensure the insulation between the connection pin to which the wire rod is connected and the magnetic core (and thus the primary winding). In this case, in the bobbin disclosed in the above-mentioned patent document, a wall-like portion protruding downward between the connection pin and the magnetic core planted in the lower ridge (parallel in FIG. 9 of the above-mentioned patent document). A protruding piece 13e) is formed, and the presence of this wall-like portion increases the creeping distance between the connection pin and the magnetic core to some extent.

  In the bobbin having such a configuration, in order to further improve the insulation between the connection pin and the magnetic core, the magnetic core is provided with an insulating coating or the height of the wall-shaped portion (from the flange portion to the wall-shaped portion). It is necessary to extend the distance) to the lower end. However, for example, when an insulating coating is applied to the magnetic core, the work is not only complicated, but the manufacturing cost of the transformer may increase due to the material cost. When the height of the wall-like part (height from the collar part to the lower end of the wall-like part) is extended, the mounting height of the transformer (distance from the component mounting surface on the board to the upper end of the transformer) is Therefore, the mounting board on which the transformer is mounted may be increased in size even though a wire with a simple coating is used to avoid increasing the size of the transformer.

  The present invention has been made in view of such problems, and provides an insulating transformer mounting substrate and a power supply device in which insulation of each part of the insulating transformer is sufficiently ensured without causing an increase in manufacturing cost or an increase in size. The main purpose is to do.

In order to achieve the above object, the insulated transformer mounting board according to the present invention has a first insulating wire wound around a bobbin to form a primary winding, and a second insulating wire wound around the bobbin. An insulating transformer mounting substrate in which a secondary winding is formed and an insulating transformer having a magnetic core mounted on the bobbin is mounted on a component mounting surface of the substrate, wherein the bobbin is mounted on the substrate A first portion connecting the primary winding to the substrate in the mounted state by connecting a contact portion that can contact the component mounting surface of the substrate in the state and both ends of the first insulating wire, respectively. 1 connection terminal group and a second connection terminal group for connecting the secondary winding to the substrate in the mounted state by connecting both ends of the second insulation wire, respectively, First connection end A first reference point having the shortest separation distance from the magnetic core among the projecting portions of at least one of the group and the second connection terminal group, and the first reference point in the magnetic core A wall-like insulating portion extending the creeping distance between the first reference point and the second reference point is provided between the first reference point and the second reference point having the shortest separation distance from the second reference point, A terminal insertion hole through which each of the first connection terminal group and the second connection terminal group can be inserted, and a slit into which the wall-like insulating portion can be inserted. The connection terminal group and the second connection terminal group are inserted into the terminal insertion hole of the substrate, the contact portion of the bobbin is contacted with the component mounting surface of the substrate, and the bobbin At least in the wall insulation With part is inserted into the slit of the substrate, wherein the magnetic core is mounted on the substrate so as to face the component mounting surface in the thickness direction of the substrate without a position within the thickness of the substrate Yes.

In the insulating transformer mounting substrate according to the present invention, the insulating transformer has a coating in which one of the first insulating wire and the second insulating wire has higher insulation than the other insulating wire. The bobbin is provided with the wall-like insulating portion with only the first connecting terminal group as the one connecting terminal group when the one insulating wire is the first insulating wire. When the one insulating wire is the second insulating wire, the wall-like insulating portion is provided with only the second connecting terminal group as the one connecting terminal group .

  Further, in the power supply device according to the present invention, the insulating transformer mounting substrate is accommodated in a casing.

  In the insulated transformer mounting substrate according to the present invention, the first separation terminal is the shortest distance from the magnetic core among the protruding portions of at least one of the first connection terminal group and the second connection terminal group. A wall-like insulating portion extending a creeping distance between the first reference point and the second reference point between the reference point and the second reference point having the shortest distance from the first reference point in the magnetic core; Provided on the bobbin of the insulation transformer, the first connection terminal group and the second connection terminal group are inserted into the terminal insertion hole of the board, the contact part of the bobbin is brought into contact with the component mounting surface of the board, An insulating transformer is mounted on the substrate such that the wall-like insulating portion of the bobbin is inserted into the slit of the substrate and the magnetic core faces the component mounting surface of the substrate. In the power supply device according to the present invention, the insulating transformer mounting substrate is housed in the casing.

  Therefore, according to the insulated transformer mounting substrate and the power supply device according to the present invention, the board components are provided by the height of the wall-shaped insulating portion inserted into the slit without providing a large hole into which the magnetic core can be inserted. The height from the mounting surface to the upper end of the insulating transformer can be reduced. Thereby, the insulation transformer mounting substrate and the power supply device can be sufficiently downsized without causing a situation where the strength of the substrate is lowered. Moreover, since it is not necessary to apply an insulating coating to the magnetic core for the purpose of ensuring the insulation between the connection terminal group and the magnetic core, the manufacturing cost of the insulating transformer mounting substrate and the power supply device can be sufficiently reduced.

  Moreover, according to the insulated transformer mounting board | substrate which concerns on this invention, and the power supply device provided with the insulated transformer mounting board, it is higher than the other insulated wire among the 1st connection terminal group and the 2nd connection terminal group. In order to insert the wall-shaped insulating portion by providing the wall-shaped insulating portion on the bobbin with only one of the connecting wires connected to the insulating wire made of the wire coated with insulating properties as one connection terminal group Since only one slit is provided on the substrate, it is possible to provide an insulating transformer mounting substrate and a power supply device including a substrate having a sufficiently high strength.

3 is a cross-sectional view of the mounting substrate 1 in the power supply apparatus 100. FIG. 2 is a plan view of a substrate 2. FIG. 3 is an external perspective view of a bobbin 20 in a transformer 3. FIG. 4 is a bottom view of a bobbin 20 in a transformer 3. FIG. FIG. 3 is an enlarged cross-sectional view of the vicinity of a wall-like insulating portion 35 of the mounting substrate 1 in the power supply device 100.

  Hereinafter, embodiments of an insulating transformer mounting substrate and a power supply device will be described with reference to the accompanying drawings.

  A power supply device 100 shown in FIG. 1 is an AC / DC converter that is an example of a “power supply device”, and includes a mounting substrate 1 housed in an insulating case (not shown). The mounting board 1 is an example of an “insulating transformer mounting board”, and is configured by mounting a transformer 3 on a board 2. Note that the actual mounting substrate 1 is configured by mounting various electronic components other than the transformer 3 on the substrate 2, but in order to facilitate understanding of the configuration of the “insulating transformer mounting substrate”, the transformer Illustration and description of electronic components other than 3 are omitted.

  The board 2 is an example of a “board”, and is configured such that the transformer 3 and the like can be mounted on the component mounting surface Fa. As shown in FIG. 2, the substrate 2 is formed in a rectangular shape as a whole, and can pass through connection terminals 41a, 41a,..., 41b, 41b,. The terminal insertion holes 11a, 11a,.., 11b, 11b,... And a slit 12 that is an example of a “slit” are formed.

  The transformer 3 is an example of an “insulating transformer”, and as shown in FIG. 1, a bobbin 20, primary windings (for example, main primary winding and auxiliary primary winding) 21a, 21b, secondary winding 22 and A magnetic core 23 is provided. The bobbin 20 is an example of a “bobbin”. As shown in FIGS. 1 and 3, a “winding frame” including a cylindrical portion 31 and flange portions 32 a and 32 b, terminal holding portions 33 a and 33 b, and abutting portions 34. , 34 and the wall-like insulating part 35 are integrally formed by a molding process using an insulating resin material as a molding material, and the connection terminals 41a and 41b are inserted during the molding process to be integrated with the terminal holding parts 33a and 33b. It has become.

  In this case, as an example, the cylindrical portion 31 is inserted through the insertion hole 31h through the core portion (center pole portion) of the upper core member (E-shaped core) 23a and the lower core member (E-shaped core) 23b (see FIG. 1). It is formed in a rectangular tube shape so that it can be made. Further, in the bobbin 20 of this example, the terminal holding portion 33a is integrally formed near one end portion of the flange portion 32b, and the terminal holding portion 33b is integrally formed near the other end portion of the flange portion 32b. Connection terminals 41a, 41a,... Integrated with the holding portion 33a (an example of “first connection terminal group”), and connection terminals 41b, 41b, integrated with the terminal holding portion 33b (“the second connection terminal group”). An example of “connecting terminal group” is sufficiently separated.

  As shown in FIGS. 1, 3 and 4, in the bobbin 20 of this example, the contact portions 34 which are brought into contact with the component mounting surface Fa of the substrate 2 are formed on the bottom surfaces of the terminal holding portions 33 a and 33 b, respectively. ing. In FIG. 4, in order to facilitate understanding of the shape of the contact portion 34, the bottom surface of the contact portion 34 (surface that is in contact with the component mounting surface Fa of the substrate 2) is filled with a mesh line. Show.

  Further, in the bobbin 20 of this example, as an example, the bottom surface of the terminal holding portion 33b in which the connection terminal 41a is integrated is not provided with a “wall-like insulating portion that is inserted into the slit of the substrate”. Only the bottom surface of the terminal holding portion 33b in which the terminal 41b is integrated is provided with a wall-like insulating portion 35 which is an example of “a wall-like insulating portion inserted into the slit of the substrate” (connection terminals 41b, 41b,... Is an example of a configuration in which “one connection terminal group” is used.

  In this case, as shown in FIG. 5, in the bobbin 20 of this example, as an example, the height H35 of the wall-like insulating portion 35 (the length from the lower end surface of the abutting portion 34 to the lower end portion of the wall-like insulating portion 35). However, the wall-shaped insulating portion 35 is formed so as to be approximately equal to the thickness T of the substrate 2 (the wall-shaped insulating portion 35 is inserted when the wall-shaped insulating portion 35 is inserted into the slit 12 of the substrate 2 as will be described later). The configuration in which the lower end portion of the portion 35 is flush with the back surface Fb of the substrate 2).

  Note that the height of the wall-like insulating portion 35 is defined to be lower than the thickness T (the lower end portion of the wall-like insulating portion 35 is the thickness T of the substrate 2 when the wall-like insulating portion 35 is inserted into the slit 12). In which the lower end portion of the wall-like insulating portion 35 extends from the back surface Fb of the substrate 2 when the wall-like insulating portion 35 is inserted into the slit 12. Projecting state). In this case, since the creepage distance between the magnetic core 23 and the connection terminal 41a can be increased as the height of the wall-shaped insulating portion 35 is increased, wall-shaped insulation is provided according to the insulation required for the transformer 3. What is necessary is just to prescribe | regulate the height of the part 35 arbitrarily.

  As shown in FIG. 1, in the transformer 3 of this example, as an example, an insulating wire is wound around the cylindrical portion 31 of the bobbin 20 to form a primary winding 21 a that is an example of a “primary winding”. Then, another insulation wire is wound around the periphery to form a secondary winding 22 which is an example of a “secondary winding”, and another insulation wire is wound around the periphery to form a “primary winding”. A primary winding 21b, which is another example of the “line”, is formed. In this case, an enamel-coated wire which is an example of a “first insulating wire” is used as the insulating wire constituting the primary windings 21a and 21b. Further, as an insulating wire constituting the secondary winding 22, a three-layer insulating wire which is an example of a “second insulating wire” (“wire material with a coating having higher insulation than the other insulating wire”) Example) is used.

  Further, in the transformer 3 of the present example, primary windings 21a and 21b each made of an insulating wire (enamel-coated wire) provided with a simple insulating coating are connected to the connection terminal 41a, and a high insulating property is achieved. A secondary winding 22 composed of an insulation wire (three-layer insulation wire) coated with a layer insulation coating is connected to the connection terminal 41b (the insulation wire constituting the secondary winding 22 is "one insulation An example of a configuration in which the connection terminals 41b, 41b,... Are “one connection terminal group”.

  In this case, in the transformer 3 of this example, as shown in FIGS. 1 and 5, the terminal holding of the “projecting part (part within the range of the length Lb)” protruding from the terminal holding part 33 a in the connection terminal 41 a. The end portion of the enameled wire for the primary windings 21a and 21b is connected within the range of the length La close to the portion 33a, and the projecting portion (length Lb of the length Lb) protrudes from the terminal holding portion 33b in the connection terminal 41b. The configuration is adopted in which the end of the three-layer insulating wire for the secondary winding 22 is connected within the range of the length La near the terminal holding portion 33b.

  Therefore, in the transformer 3 of this example, the end portions of the respective insulation wires connected to the connection terminals 41a and 41b do not touch the component mounting surface Fa of the board 2 so that the bottom portions of both terminal holding portions 33a and 33b are high. By providing the abutting portions 34 and 34 of length H34 (see FIG. 5), the state where the range of the length La of the connection terminals 41a and 41b is located on the component mounting surface Fa side of the substrate 2 is maintained. Configuration is adopted.

  In manufacturing the mounting substrate 1, first, the transformer 3 is manufactured. Specifically, the primary winding 21a is formed by winding an enamel-coated wire around the cylindrical portion 31 of the previously formed bobbin 20. At this time, both ends of the wound enamel-coated wire are connected to the pair of connection terminals 41a and 41a held by the terminal holding part 33a, respectively. In manufacturing the transformer 3, an insulating tape is disposed at an arbitrary position as necessary. However, in order to facilitate understanding of the manufacturing method of the transformer 3, illustration and description regarding the insulating tape are omitted.

  Next, the secondary winding 22 is formed by winding a three-layer insulation wire around the primary winding 21a. At this time, both ends of the wound three-layer insulation wire are connected to the pair of connection terminals 41b and 41b held by the terminal holding part 33b, respectively. Subsequently, the primary winding 21 b is formed by winding an enamel-coated wire around the secondary winding 22. At this time, both ends of the wound enamel-coated wire are connected to the other pair of connection terminals 41a and 41a held by the terminal holding portion 33b.

  In this case, the enamel-coated wire has a very small diameter compared to the three-layer insulated wire because the insulation coating is thin. Therefore, in the transformer 3 in which the primary windings 21a and 21b having a larger number of turns than the secondary winding 22 are formed by the enameled coated wire, an insulating wire having a necessary and sufficient number of turns is wound without increasing the size of the bobbin 20. Primary windings 21a and 21b can be formed. Thereafter, the upper core member 23a and the lower core member 23b are mounted so as to sandwich the bobbin 20 in which the primary winding 21a, the secondary winding 22 and the primary winding 21b have been formed. Thereby, the magnetic core 23 is formed and the transformer 3 is completed.

  Subsequently, the transformer 3 is mounted on the substrate 2. Specifically, as shown in FIG. 1, the connection terminals 41a, 41a,... Are inserted into the terminal insertion holes 11a, 11a, and the connection terminals 41b, 41b,. The transformer 3 is placed on the substrate 2 so that both the abutting portions 34 and 34 abut against the component mounting surface Fa and the wall-like insulating portion 35 is inserted into the slit 12. Thereafter, in a state where other electronic components other than the transformer 3 are placed on the component mounting surface Fa, the respective connection terminals 41a, 41a,..., 41b, 41b,. Each of the connection terminals is soldered to the wiring pattern, whereby the mounting of the transformer 3 is completed and the mounting substrate 1 is completed.

  In the transformer 3 mounted on the mounting substrate 1, as shown in FIG. 5, the “protruding portion (projecting portion) protruding from the terminal holding portion 33 b at the connecting terminals 41 b, 41 b... As“ at least one connecting terminal group ”. A reference point P1 (an example of a “first reference point”) having the shortest separation distance from the magnetic core 23 (in this example, the lower core member 23b) among the “parts within the range of the length Lb”; Reference points P1 and P2 between the magnetic core 23 (lower core member 23b) and the reference point P2 (an example of the “second reference point”) that is the shortest distance from the “projection part” of the connection terminal 41b. A contact portion 34 and a wall-like insulating portion 35 are provided so as to extend the creepage distance therebetween.

  In the transformer 3 in the mounting substrate 1 of this example, the bobbin 20 is formed so that the lower end surface of the magnetic core 23 (lower core member 23b) is substantially the same height as the lower end surfaces of the terminal holding portions 33a and 33b. Therefore, not only the wall-shaped insulating portion 35 but also the abutting portion 34 functions as a “wall-shaped insulating portion” that extends the creeping distance between the reference points P1 and P2. However, as described above, the abutting portion 34 prevents the insulating wire connected within the range of the length La of the connection terminals 41a and 41b from being in contact with the component mounting surface Fa of the substrate 2. For example, when the design is changed so that the lower end surface of the magnetic core 23 (lower core member 23b) is positioned at the same height as the lower end surface of the contact portion 34, the wall Only the insulative part 35 functions as a “wall-like insulating part”.

  As for the “contact portion”, the position where the contact portion 34 is formed on the bobbin 20 of this example as long as it is possible to prevent the insulated wires connected to the connection terminals 41a and 41b from being in contact with the component mounting surface Fa. It can be formed at a different position. Therefore, when a configuration in which no “contact portion” exists between the reference points P1 and P2, the height H34 of the contact portion 34 in the bobbin 20 and the height H35 of the wall-shaped insulating portion 35 are combined. By providing the “wall-like insulating portion” between the reference points P1 and P2, it is possible to ensure the insulating property, which will be described later, similar to the transformer 3 of this example.

  In this case, in the transformer 3 in the mounting substrate 1 of this example, in order to wind an insulation wire having a necessary number of turns without causing an increase in the size of the bobbin 20, the enamel-coated wire with a simple insulation coating is primary. Windings 21a and 21b are formed. Therefore, in the transformer 3 in which the magnetic core 23 is disposed in the vicinity of the primary windings 21a and 21b, the potential of the magnetic core 23 when energized is considered to be approximately the same as the potential of the primary windings 21a and 21b for safety standards. Necessary insulation measures must be taken. For this reason, in the transformer 3 of this example, the insulation between the primary windings 21a and 21b and the secondary winding 22, the insulation between the primary windings 21a and 21b and the connection terminal 41b, and the secondary winding It is necessary to ensure not only the insulation between the wire 22 and the connection terminal 41a, but also the insulation between the magnetic core 23 and the secondary winding 22, and the insulation between the magnetic core 23 and the connection terminal 41b. There is.

  In this case, insulation between the primary windings 21a, 21b and the secondary winding 22 is ensured by forming the secondary winding 22 with a three-layer insulation wire having high insulation. Further, between the primary windings 21a and 21b and the connection terminal 41b, the terminal holding portion 33b is sufficiently high so that the connection terminal 41b is sufficiently separated from the enamel wire wound around the cylindrical portion 31. As a result, insulation is ensured. Furthermore, between the secondary winding 22 and the connection terminal 41a, in addition to forming the secondary winding 22 with a three-layer insulated wire, the terminal holding portion 33a is sufficiently raised to surround the cylindrical portion 31. The insulation is ensured by sufficiently separating the connection terminal 41a from the wound three-layer insulation wire. In addition, insulation between the magnetic core 23 and the secondary winding 22 is ensured by forming the secondary winding 22 with a three-layer insulating wire.

  Furthermore, between the magnetic core 23 and the connection terminal 41b, a contact portion 34 and a wall-like insulating portion 35 are provided between the reference points P1 and P2 to sufficiently increase the creepage distance between the reference points P1 and P2. Insulation is secured by extending. Specifically, in a bobbin (not shown) in which the contact holding part 34 and the wall-like insulating part 35 are not present in the terminal holding part 33b, the creeping distance between the reference points P1 and P2 is the distance L shown in FIG. On the other hand, in the bobbin 20 of the present example provided with the contact portion 34 and the wall-like insulating portion 35, the creeping distance between the reference points P1 and P2 is the total length of the height H34 and the height H35 shown in FIG. It is a very long distance obtained by adding the distance L to twice the distance. The creepage distance between the reference points P1 and P2 is the distance L to the creepage distance (twice the height H34 shown in FIG. 5) on the bobbin (not shown) where the wall-like insulating portion 35 does not exist in the terminal holding portion 33b. It is sufficiently longer than the total distance).

  In this case, in order to ensure insulation between the magnetic core 23 and the connection terminal 41b, a “wall-like insulating portion” is obtained by summing the height H34 of the abutting portion 34 and the height H35 of the wall-like insulating portion 35. When the required transformer 3 is mounted on a “board” in which an element corresponding to the slit 12 in the board 2 is not provided, the lower end portion of the wall-shaped insulating portion 35 is in contact with the “component mounting surface”. Therefore, the mounting height from the “component mounting surface” of the “board” to the upper end of the transformer 3 (transformer 3) becomes high. On the other hand, in the mounting substrate 1 of this example in which the transformer 3 is mounted on the substrate 2 with the wall-shaped insulating portion 35 inserted in the slit 12, the insulation between the magnetic core 23 and the connection terminal 41b is impaired. Instead, the height (mounting height of the transformer 3) from the component mounting surface Fa of the substrate 2 to the upper end portion of the transformer 3 is lowered by the height H35 of the wall-like insulating portion 35 inserted into the slit 12.

  On the other hand, in order to further reduce the height from the “component mounting surface” of the “board” to the upper end portion of the transformer 3, not only the wall-shaped insulating portion 35 but also a part of the contact portions 34, 34 are “board”. When it is going to employ | adopt the structure located in the range of thickness of this, it will be necessary to provide two slits which can insert both contact parts 34 and 34 in a "board | substrate." Further, in order to further reduce the height from the “component mounting surface” of the “board” to the upper end portion of the transformer 3, the positions and shapes of the connection terminals 41 a and 41 b are appropriately changed so that a part of the magnetic core 23 is “ When it is intended to adopt a configuration that is positioned within the thickness range of the “substrate”, it is necessary to provide a large hole in the “substrate” into which the magnetic core 23 or the like can be inserted.

  For this reason, when trying to further reduce the height from the “component mounting surface” of the “board” to the upper end of the transformer 3, only one slit 12 is provided to insert the wall-like insulating part 35 in the transformer 3. There is a possibility that the strength of the “board” on which the transformer 3 is mounted is lowered as compared with the board 2 in the formed mounting board 1 of this example. On the other hand, in the board 2 in the mounting board 1 of the present example, the magnetic core 23 of the transformer 3 is in a state of facing the component mounting surface Fa, and a large hole for inserting the magnetic core 23 and the like is formed. Unlike the “substrate”, sufficient strength is secured.

  Thereafter, the mounting substrate 1 is accommodated in a resin case (not shown) to complete the AC / DC converter (not shown).

  As described above, in the mounting substrate 1, the “protrusion” in the connection terminal group (in this example, the connection terminals 41 b, 41 b...) Of the connection terminals 41 a, 41 a. The creepage distance between the reference points P1 and P2 is between the reference point P1 having the shortest separation distance from the magnetic core 23 and the reference point P2 having the shortest separation distance from the reference point P1 in the magnetic core 23. The extending wall-like insulating portion 35 is provided on the bobbin 20 of the transformer 3, the connection terminals 41 a and 41 b are inserted into the terminal insertion holes 11 a and 11 b of the substrate 2, and the contact portions 34 and 34 of the bobbin 20 are components of the substrate 2. Based on the transformer 3, the wall-like insulating portion 35 of the bobbin 20 is inserted into the slit 12 of the substrate 2 and the magnetic core 23 faces the component mounting surface Fa of the substrate 2. It has been implemented in 2. In the power supply device 100, the mounting substrate 1 is housed in a casing.

  Therefore, according to the mounting substrate 1 and the power supply device 100, without providing a large hole in the “substrate” into which the magnetic core 23 can be inserted, only the height H35 of the wall-shaped insulating portion 35 inserted into the slit 12 is obtained. The height from the component mounting surface Fa of the substrate 2 to the upper end of the transformer 3 can be reduced. Thereby, the mounting substrate 1 and the power supply device 100 can be sufficiently downsized without causing a situation where the strength of the substrate 2 is reduced. In addition, since it is not necessary to apply an insulating coating to the magnetic core 23 for the purpose of ensuring the insulation between the connection terminal 41b and the magnetic core 23, the manufacturing costs of the mounting substrate 1 and the power supply device 100 can be sufficiently reduced. it can.

  In addition, according to the mounting substrate 1 and the power supply device 100, the insulating wire (the book) made of a wire having a coating having higher insulation than the other insulating wire of the connecting terminal 41a and the connecting terminal 41b. In the example, the wall-like insulating portion 35 is provided on the bobbin 20 with only one (in this example, the connection terminal 41b) to which the three-layer insulation wire is connected as the "one connection terminal group", thereby providing a "wall-like Since the number of “slits” provided in the “substrate” for inserting the “insulating portion” is only one (in this example, only the slit 12), the mounting substrate 1 and the power supply device including the substrate 2 having sufficiently high strength are provided. 100 can be provided.

  Note that the configurations of the “insulating transformer mounting substrate” and the “power supply device” are not limited to the configuration examples of the mounting substrate 1 and the power supply device 100 described above. For example, the configuration in which the wall-shaped insulating portion 35 as the “wall-shaped insulating portion” is provided only in the terminal holding portion 33b has been described as an example, but the terminal holding portion 33a has the same “wall” as the wall-shaped insulating portion 35. ”-Like insulating portion” can be provided. When the “bobbin” having such a configuration is adopted, in addition to the slit 12, a “slit” into which the wall-like insulating portion 35 formed in the terminal holding portion 33a can be inserted may be provided.

  In addition, the bobbin 20 in which the connection terminals 41a and 41b are held in the terminal holding portions 33a and 33b by insert molding has been described as an example. However, the configuration of the “bobbin” is not limited to this example. It is also possible to adopt a configuration in which the connection terminals 41a and 41b are held by being press-fitted into terminal insertion holes formed in advance in portions corresponding to the terminal holding portions 33a and 33b. Furthermore, although the example which comprised the magnetic core 23 by the upper core member 23a comprised by the E-shaped core and the lower core member 23b was demonstrated, the structure of a "magnetic core" is not limited to this, An E-shaped core, I A configuration in which a “magnetic path” similar to that of the magnetic core 23 is formed by appropriately combining a character core, a T-shaped core, a C-shaped core, and the like can be employed.

  Further, the power supply device 100 (AC / DC converter) which is an example of the “power supply device” has been described as an example. However, in the various “power supply devices” such as a DC / DC converter and a DC / AC converter, the mounting board described above is used. 1 can be adopted.

DESCRIPTION OF SYMBOLS 100 Power supply device 1 Mounting board 2 Board | substrate 3 Transformer 11a, 11b Terminal insertion hole 12 Slit 20 Bobbin 21a, 21b Primary winding 22 Secondary winding 23 Magnetic core 23a Upper core member 23b Lower core member 31 Cylindrical part 31h Insertion hole 32a , 32b Flange portion 33a, 33b Terminal holding portion 34 Abutting portion 35 Wall-like insulating portion 41a, 41b Connection terminal Fa Component mounting surface Fb Back surface H34, H35 Height L Distance La, Lb Length P1, P2 Reference point T Thickness

Claims (3)

A first insulated wire is wound around a bobbin to form a primary winding, and a second insulated wire is wound around the bobbin to form a secondary winding, and a magnetic core is attached to the bobbin. An insulated transformer mounting board in which the insulated transformer is mounted on the component mounting surface of the board,
In the mounted state, the bobbin is connected to a contact portion that can contact the component mounting surface of the substrate in a mounted state mounted on the substrate and both end portions of the first insulating wire. A first connection terminal group for connecting the primary winding to the substrate and both ends of the second insulating wire are connected to each other to connect the secondary winding to the substrate in the mounted state. 2 connection terminal groups, and the separation distance from the magnetic core is the shortest among the protruding portions of at least one of the first connection terminal groups and the second connection terminal groups. The creepage distance between the first reference point and the second reference point is between the first reference point and the second reference point having the shortest separation distance from the first reference point in the magnetic core. Extending wall insulation Is configured provided,
The substrate is provided with a terminal insertion hole through which the first connection terminal group and the second connection terminal group can be inserted, and a slit into which the wall-like insulating portion can be inserted,
In the insulating transformer, the first connection terminal group and the second connection terminal group are inserted into the terminal insertion hole of the board, and the abutting portion of the bobbin contacts the component mounting surface of the board. And at least a portion of the wall-like insulating portion of the bobbin is inserted into the slit of the substrate, and the magnetic core is not positioned within the thickness range of the substrate, and the thickness direction of the substrate the component mounting surface and in which an insulating transformer mounting board is implemented on the substrate so as to face in. The insulating transformer is composed of a wire material provided with a coating in which either one of the first insulating wire and the second insulating wire has a higher insulating property than the other insulating wire,
The bobbin is provided with the wall-shaped insulating portion with only the first connecting terminal group as the one connecting terminal group when the one insulating wire is the first insulating wire, and the one insulating wire is 2. The insulated transformer mounting substrate according to claim 1, wherein when the second insulating wire is used, the wall-like insulating portion is provided with only the second connecting terminal group as the one connecting terminal group.   A power supply apparatus in which the insulating transformer mounting board according to claim 1 is accommodated in a casing.

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