JPH11186074A - Electromagnetic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an electromagnetic device which is capable of improving power efficiency, while surely maintaining lamination state of a core plate. SOLUTION: An electric discharge lamp stabilizer has a core structure body 26 formed of a side leg core 41, formed by laminating a plurality of core plates 41a, 42a and holding lamination state thereof and a central leg core 42, a coil 25 which is formed by winding conductors 29, 30 on coil bobbins 27, 28 and is fit to the core 42. Laminated core plates are bonded mutually by adhesives 45, 46 which are extended and provided in a thickness direction of the cores 41, 42, and laminated state of the core plates 41a, 42a is maintained. A material which causes little punching strain which becomes magnetic path resistance of a core structure body 26 can be adopted for each of core plates 41a, 42a and laminated state of the core plates 41a, 42a can be kept without providing the cores 41, 42 with a welding trace which turns into an eddy current path which flows over the entire central leg core 42 during energization.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic device such as a discharge lamp ballast such as a transformer or a choke coil provided in a fluorescent lighting device, and more particularly, to a laminated state in which a plurality of iron core plates are laminated. TECHNICAL FIELD The present invention relates to an electromagnetic device provided with an iron core holding the above.

[0002]

2. Description of the Related Art Electromagnetic devices such as a discharge lamp ballast have an iron core structure, and a conventional example of this structure is shown in FIGS. The iron core structure indicated by 1 in these figures comprises a side leg iron core 2 having a rectangular shape in plan view and a center leg iron core 3 having a cross shape in plan view. This side leg iron core 2 is pressed into the center in the width direction.
Has been combined with. As shown by the two-dot chain line in FIG. 19, the coil 4 in which the first conductor (copper wire) 4b is wound around the coil bobbin 4a and the second conductor (copper wire) 5b around the coil bobbin 5a around the center leg iron core 3. Coil 5
Are fitted.

As shown in FIG. 18, the side leg iron core 2 is formed by laminating a plurality of thin iron core plates 2a punched to the same size and holding the laminated state by the following connecting means. That is, connecting portions 2b are formed at a plurality of positions of each iron core plate 2a, each having a recess formed on one surface side of the iron core plate 2a and a projection projecting corresponding to the recess on the other surface side. I have. Then, the recess of the connecting portion 2b of one of the core plates 2a of the adjacent core plates 2a is inserted into the recess of the other core plate 2a.
Each of the iron core plates 2a is held in a laminated state by press-fitting the convex portions of the connecting portions 2b.

Similarly, as shown in FIG. 18, the center leg core 3 is also formed by laminating a plurality of thin core plates 3a punched to the same size, and connecting the laminated state similarly to the side leg core 2. Held by means. That is, connecting portions 3b are formed at a plurality of locations of each iron core plate 3a. The connecting portions 3b each have a concave portion formed on one surface side of the iron core plate 3a and a convex portion projecting corresponding to the concave portion on the other surface side. I have. Then, the connecting portion 3b of one of the adjacent iron core plates 3a
By press-fitting the protrusion of the connecting portion 3b of the other iron core plate 3a into the recess, and stacking it, the stacked state of each iron core plate 3a is maintained.

[0005] The center leg iron core 3 to which the coils 4 and 5 are fitted and attached has a joint end 6 comprising both ends in the longitudinal direction formed on the inner surface of the shorter frame portion of the side leg iron core 2. By press-fitting into the recesses 7, respectively, they are disposed inside the side leg cores 2 as shown in FIG. 19, and form a closed magnetic path together with the side leg cores 2.

Another conventional example of an iron core structure is shown in FIGS. 20 and 21. FIG. The iron core structure indicated by 1 in these figures is composed of a side leg core 2 having a rectangular shape in plan view and a center leg core 3 having an I-shaped plan shape. And is combined with the side leg core 2 by press-fitting at the center in the width direction. A coil (not shown) in which a conductor (copper wire) is wound around a coil bobbin is fitted to the center leg iron core 3.

As shown in FIG. 20, the side leg iron core 2 is formed by laminating a plurality of thin iron core plates 2a punched to the same size and holding the laminated state by welding. This welding is continuously performed on both side surfaces of the side leg iron core 2 in the thickness direction (the laminating direction) of the iron core plate 2a. Reference numerals 8a and 8b shown in FIG.

Similarly, the center leg iron core 3 is formed by laminating a plurality of thin iron core plates 3a punched to the same size and holding the laminated state by welding. This welding is continuously performed on both side surfaces of the center leg core 3 in the thickness direction (lamination direction) of the core plate 3a. Reference numerals 9a and 9b shown in FIGS. Is shown.

The center leg iron core 3 into which the coil is fitted has a joint end 6 comprising both ends in the longitudinal direction in a joint recess 7 formed on the inner surface of the shorter frame of the side leg iron core 2. By press-fitting, it is arranged inside the side leg iron core 2 and forms a closed magnetic path together with the side leg iron core 2.

[0010]

In the prior art shown in FIGS. 18 and 19, the provision of the connecting portions 2b and 3b increases the punching distortion of the iron core plates 2a and 3a. As shown in FIG. 21, the magnetic resistance of the magnetic path becomes larger due to the punching distortion as compared with the case where the iron core plates are simply laminated. Therefore, in a choke coil, a transformer, and the like using the iron core structure 1 shown in FIGS. 18 and 19, there is a problem that iron efficiency increases and power efficiency decreases.

In the conventional example shown in FIGS. 20 and 21, the metal structures of the iron core plates adjacent to each other in the lamination direction at the welding marks 8a, 8b, 9a, 9b are fused. The electric resistance is smaller than that of the other simply laminated portions, so that the current can easily flow. Therefore, the structure of the discharge lamp ballast including the center leg iron core 3 having the welding traces 9a and 9b provided on both sides in the thickness direction as described above has the following problems.

That is, when the discharge lamp ballast is used, an alternating magnetic flux passes through the two iron cores 2 and 3, and accordingly, an eddy current that generates a magnetic flux in a direction that prevents a change in the magnetic flux is generated.
The welding marks 8a, 8
b or 9a, 9b as a passage and flows into the two cores 2, 3. In this case, not only does the eddy current easily escape to the outside through a metal case (not shown) that accommodates the iron core structure 1, but also, compared to the side leg iron core 2 in which an air gap is provided between the iron core structure 1 and the center leg iron core 3. On the other hand, a large eddy current flows through the center leg iron core 3 because the coil current flowing through the conductor of the coil fitted thereto interlinks.

The eddy current flowing through the center leg core 3 is indicated by arrows D and E in FIG. Arrow F in FIG. 21 indicates the flow direction of the magnetic flux. The thin line arrow D indicates the eddy current flowing individually inside each core plate 3a, and the solid line arrow E indicates the central leg iron core with the upper and lower ends core plates 3a arranged at both ends in the stacking direction and the welding traces 9a and 9b as passages. The current value flowing over the entire 3 indicates a large eddy current. The upper and lower two iron core plates 3a adjacent in the laminating direction and the welding traces 9 corresponding thereto
Although eddy currents partially flow through the center leg iron core 3 even when a part of the eddy currents a and 9b are used as passages, these are not shown and the current values of these eddy currents and the eddy current indicated by the thin arrow D are Is smaller than the current value of the eddy current indicated by the solid arrow E.

When an eddy current flows between the iron core plates 3a in the central leg iron core 3 through the welding traces 9a and 9b as passages, iron loss in the central leg iron core 3 increases and power is consumed with heat generation. You. Therefore, in a choke coil, a transformer, or the like using the iron core structure 1 configured as described above, there is a problem that the loss due to the eddy current is large and the power efficiency is poor.

Accordingly, a first object of the present invention is to provide an electromagnetic device capable of improving power efficiency while reliably maintaining a laminated state of iron core plates.

A second problem to be solved by the present invention is as follows.
In order to solve the first problem, it is an object of the present invention to provide an electromagnetic device capable of further improving performance of holding iron core plates in a stacked state.

A third problem to be solved by the present invention is as follows.
In solving the second problem, it is an object of the present invention to provide an electromagnetic device that can improve manufacturability.

[0018]

According to the present invention, there is provided an iron core structure formed by laminating a plurality of iron core plates and holding the laminated state, and a conductor wound around a coil bobbin and a coil bobbin. It is assumed that the electromagnetic device includes at least one coil that is fitted to the coil bobbin in the center leg iron core of the iron core structure and is combined with the iron core structure.

In order to solve the first problem, the invention according to claim 1 is characterized in that the laminated iron core plates are bonded to each other with an adhesive extending in the thickness direction of the iron core. Characterized by maintaining the laminated state of

According to the first aspect of the present invention, since the laminated iron core plates are adhered to each other with an adhesive extending in the thickness direction of the iron core, the laminated state of the iron core plates is maintained. Can be reliably held.
Moreover, since the laminated state of the iron core plates is maintained by bonding as described above, welding traces having a small electric resistance used as an eddy current path are not provided on the iron core, and the magnetic path of the iron core structure is not provided. It is not necessary to use an iron core plate with a connecting portion having a punching distortion, which causes a magnetic resistance, to form a core by stacking and holding the iron core plates, so that iron loss of each iron core can be reduced.

[0021] In order to solve the second problem, the invention according to claim 2, which is dependent on the invention of claim 1, forms a groove extending in the thickness direction of the iron core, and forms the adhesive in the groove. It is characterized by providing an agent.

In the invention of claim 2, claim 1
In addition to the effect of the invention, the groove provided in the iron core can increase the bonding area provided by the adhesive provided inside the core.

In order to solve the third problem, the invention according to claim 3 is dependent on the invention according to claim 2, wherein the outermost core plate is provided with both ends of the concave groove positioned at both ends in the stacking direction of the iron core. It is characterized by being closed by.

According to the third aspect of the present invention, the second aspect is provided.
In addition to the function of the invention of the above, the following function is provided. That is, when a number of core plates corresponding to a plurality of cores are laminated, the concave grooves of each core are discontinuous due to the outermost core plates of the adjacent cores, but are arranged in a line in the laminating direction of the cores. Provided. Then, in this state, by continuously applying the adhesive over the respective concave grooves arranged in a row as described above, the iron core plates of a plurality of iron cores can be simultaneously bonded, and the laminated state can be maintained. In this bonding, the bonding area is large in the groove and the bonding strength can be secured large, but the bonding area is small between the outermost core plates of the cores separating the adjacent grooves. Is small. Therefore, when the cores laminated and bonded as described above are made independent after the bonding, the cores can be easily separated at the boundary between adjacent outermost core plates by utilizing the difference in the bonding strength. Can be done.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS.

The electromagnetic device according to the first embodiment is a discharge lamp ballast 20, which comprises a transformer body (electromagnetic device body) 21 and a steel plate 22 as shown in FIG.
And a steel plate cover 23 which is caulked to both side edges 22 a of the bottom plate 22. Bottom plate 22
And the cover 23 form a ballast case (electromagnetic device case). In FIG. 5, reference numeral 24 denotes a synthetic resin terminal cover which covers the terminal fittings, which will be described later, exposed from the cover 23 and is attached to the transformer body 21 by claw engagement, and wires facing the respective terminal fittings. It has an insertion hole. The discharge lamp stabilizer 20 is used by attaching a bottom plate 22 to a chassis of a lighting fixture (not shown) by screwing or the like.

As shown in FIGS. 1 and 2, the transformer main body 21 includes a coil 25 and a press-fit assembled iron core structure 26. The coil 25 has coil bobbins 27 and 28 made of synthetic resin, one of which is wound with a primary conductor 29 made of copper wire, and the other is provided with a secondary conductor 30 made of copper wire. It is wound. Although the coil bobbins 27 and 28 are formed integrally, in the present invention, separately formed ones may be used in combination.

The coil bobbin flanges 27a, 27a,
Terminal blocks 31 and 32 are integrally formed on the outer surface of 8a, respectively. One or more terminal fittings 33 are attached to one terminal block 31, and one or more terminal fittings 34 are similarly attached to the other terminal block 32. These terminal fittings 33, 3
4 are required depending on the winding structure.
Lead wires and the like (not shown) inserted through the terminal portions and intermediate portions of the terminals 9 and 30 and the wire insertion holes of the terminal cover 24 are connected.

In FIG. 1 and FIG. 2, reference numeral 35 denotes an introduction portion integrally provided on the outer surfaces of the bobbin flanges 27a and 28a.
In FIG. 1 and FIG.
5a is provided. The arc-shaped introduction surface of the introduction portion 35 is continuous with the joint end surface of the center leg iron core, which will be described later, thereby enabling proper press-fit assembly while preventing the inclination of the center leg iron core in assembling the core structure 26. It is supposed to.

As shown in FIG. 1 to FIG.
6 is formed from two or more iron cores, for example, a side leg iron core 41 and a center leg iron core 42. The side leg iron core 41 is formed by stacking a plurality of iron core plates 41a made of a thin steel plate punched out to the same size in a rectangular frame shape when viewed from above, and adjacent to the core plate in the thickness direction (stacking direction). By adhering each other 41a with an adhesive 45, they are assembled while maintaining the laminated state. As the iron core plate 41a held in a laminated state by bonding as described above, a core plate having a concave portion on one surface and having no connecting portion protruding from the other surface is used.
The side leg iron core 41 has a short frame portion 4 opposed in the longitudinal direction.
1A has a joint recess 43 on the inner surface at the center.
These joint concave portions 43 are concave portions forming an arc shape in the width direction of the side leg iron core 41.

The bonding may be performed on the outer surface or the inner surface of the side leg core 41, but in the present embodiment, the pair of short frame portions 41A has a central outer surface in the longitudinal direction and a pair of long frames extending in the longitudinal direction of the side leg core 41. The adhesive is applied to the outer surface at the center in the longitudinal direction of the portion 41B so as to extend in the entire thickness direction of the side frame core 41. Adhesive 45 provided on short frame portion 41A
Is a side leg region corresponding to the width of the joint end of the center leg core 42 pressed into the side leg core 41, in other words, the side leg core 4
It is included in a region 41 </ b> C sandwiched between the extension lines of both side surfaces of the center leg iron core 42 press-fitted into 1, and corresponds to the joint concave portion 43.

As shown in FIG.
Is formed by laminating a plurality of iron core plates 42a made of a thin steel plate punched into the same size in a plane shape having a cruciform shape having a projecting portion integrally on both side surfaces in the longitudinal center portion, and having an outer periphery thereof. The iron core plates 42a adjacent to each other in the thickness direction (lamination direction) on the surface are bonded to each other with an adhesive 46,
It is assembled while maintaining the laminated state. Both ends in the longitudinal direction of the center leg iron core 42 are used as joint end portions 42E which are press-fitted into the joint concave portions 43, and the end surfaces thereof, that is,
The joint end surface 42E1 is formed by a circular arc surface in the width direction.
Further, the protruding portions are laminated with each other to form the long frame portion 41.
A leakage convex portion 44 is formed so as to approach and face the inner surface of the central portion of B. The bonding to the center leg iron core 42 is performed by applying an adhesive 46 extending over the entire thickness direction of the center leg iron core 42 at the joint end surface 42E1 and the tip of the leakage convex portion 44.

As the adhesives 45 and 46, a thermosetting adhesive such as an epoxy-based thermosetting adhesive, or a room temperature setting adhesive such as a two-part room temperature setting adhesive can be used. 1 and 2 is the bobbin flange 2.
Claws protruded integrally from the outer surfaces of 7a and 28a. The terminal covers 24 are attached to the transformer main body 21 by being hooked on these.

To assemble the transformer main body 21 included in the discharge lamp ballast 20 having the above-described structure, as shown in FIG. 1 and FIG. 41 are set on a press-fitting machine (not shown) via a jig or the like, and a pressurizing tool of the press-fitting machine, for example, as shown by an arrow G in FIG.
This is performed by pressing the upper surface of the joint end portion 42E of the center leg iron core 42 protruding from the inner leg core 41 into the inside of the side leg iron core 41. In this case, before the joint end 42E is pressed into the joint recess 43, the coil bobbin 2
Since the introduction portions 35 of 7 and 28 slide through the inner surface of the joint concave portion 43 and guide the joint end portion 42E to the joint concave portion 43, the press-fitting is performed while maintaining the parallelism of the central leg iron core 42 with the side leg iron core 41. Can be done. The structure of the transformer main body 21 formed by the above procedure is shown in FIG.
The structure of only the assembled core structure 26 is shown in FIG. Then, by the press-fitting, the joint end surface 42E1 of the center leg iron core 42 is pressed against the inner surface of the joint concave portion 43 of the side leg iron core 41 to form a closed magnetic path extending between both iron cores 41 and 42, and the long length of the side leg iron core 41 is increased. Inner surface of frame portion 41B and leakage convex portion 4
4, an air gap g for magnetic leakage is formed.

The side leg core 41 and the center leg core 42 forming the iron core structure 26 provided in the discharge lamp ballast 20 having the above-described structure.
Are a plurality of laminated core plates 41a and the core plates 4a.
The lamination state of each of the members 2a is maintained by the adhesives 45 and 46 without using welding.

Therefore, as will be described with reference to the center leg core 42 where the coil currents flowing through the conductors 29 and 30 are linked, the center leg core 42 is intended to cancel the AC magnetic flux passing through it in the longitudinal direction. Since no welding trace having a small electric resistance used as an eddy current path for generating a magnetic flux is generated, an eddy current generated in the center leg core 42 is mainly generated inside each iron core plate 42a. (See arrow D indicated by a thin line in FIG. 6, and F in FIG. 6 indicates the direction of the coil current.) Therefore, iron loss caused by eddy current inside the center leg iron core 42 at the time of energization can be reduced, and accordingly, the power efficiency of the discharge lamp ballast 20 can be improved, and naturally, a rise in temperature due to heat generation can also be suppressed. it can.

Similarly, in maintaining the laminated state, a connecting part which is recessed on one surface and protrudes from the other surface is provided on the iron core plate as in the prior art, and these connecting parts are pressed into each other to maintain the laminated state. Since it is not necessary to adopt a structure, a plate-shaped core plate having no connecting portion as described above can be used for each of the core plates 41a and 42a. for that reason,
Since the magnetic resistance in the magnetic path of the iron core structure 26 does not increase as in the case where the connecting portion is provided, it is possible to prevent an increase in iron loss, thereby improving the power efficiency of the discharge lamp ballast 20, Naturally, a rise in temperature due to heat generation can also be suppressed.

Further, in the first embodiment, in maintaining the laminated state of the core plates 42a of the center leg iron core 42,
Since the bonding is performed by applying and bonding the adhesive 46 to at least the joint end surface 42E1, the strength of the joint end 42E of the center leg iron core 42 can be increased. Therefore, when assembling the core structure 26 by press-fitting the center leg iron core 42 into the side leg iron core 41 as described above, a predetermined laminated state is maintained by withstanding the upward force in the thickness direction acting on the joint end 42E. Therefore, irrespective of the force that the joint end 42E receives in the thickness direction,
The core plate 42a can be prevented from peeling or warping.

Similarly, in order to maintain the laminated state of the core plates 41a of the side leg cores 41, at least the adhesive 45 is applied to the outer surface of the region 41C located between the extension lines on both sides of the central leg core 42. As described above, when the center leg core 42 is pressed into the side leg core 41 as described above, the region 41C in which a force acts downward on the frame portion 41A of the side leg core 41 in the thickness direction. Strength, adhesive 45
Can be increased. Therefore, the center leg iron core 42
Similarly to the above, it is possible to prevent the core plate 41a forming the side leg iron core 41 from peeling off or warping despite the fact that the region 41C receives a downward force in the thickness direction during the press-fitting.

FIGS. 7 to 10 show a second embodiment of the present invention. This embodiment has basically the same configuration as that of the first embodiment. Therefore, the same components are denoted by the same reference numerals as those of the first embodiment, and the configuration and operation will be described. Are omitted, and different portions will be described below. The difference between the second embodiment and the first embodiment is the structure of the portion where the adhesives 45 and 46 are provided.

That is, each frame portion 41A of the side leg iron core 41,
A concave groove 61 extending continuously over the entire thickness direction of the iron core 41 is formed on the outer surface of the central portion of the iron core 41B in the longitudinal direction. In order to form these grooves 61, FIG.
As shown in FIG. 2, a core plate 41a having a notch 61a provided in a corresponding portion is employed, and by stacking these iron core plates 41a, the notches 61a are connected to form the concave grooves 6a.
I have one. Then, the adhesives 45 are applied to the insides of the concave grooves 61 so as to extend in the thickness direction of the side leg iron cores 41, respectively, so that the laminated state of the iron core plates 41a stacked by the adhesives 45 is maintained. The side leg iron core 41 is assembled.

Similarly, each joint end surface 42 of the center leg iron core 42
A concave groove 62 extending continuously over the entire thickness direction of the iron core 42 is formed on the distal end surface of E1 and each of the leakage convex portions 44, respectively. In order to form these concave grooves 62,
As shown in FIG. 10, a core plate 42a provided with a notch 62a in a corresponding portion is employed.
The notches 62a are made continuous by stacking 2a to obtain the concave grooves 62. An adhesive 46 is applied to each of the concave grooves 62 so as to extend in the thickness direction of the center leg iron core 42, so that the iron core plates 42 a stacked by these adhesives 46 are kept in a laminated state. The leg iron core 42 is assembled. The configuration other than the above is the same as that of the first embodiment, including the configuration not shown in FIGS.

In the configuration of the second embodiment,
Since the laminated state of the plurality of iron core plates 41a is held by the adhesive 45 and the laminated state of the plurality of iron core plates 42a is held by the adhesive 46, the present invention is used for the reason already described in the first embodiment. Can be solved. Moreover,
Since the portions where the adhesives 45 and 46 are provided are the concave grooves 61 and 62, a large bonding area can be ensured, and accordingly, the bonding strength can be improved and the assembling strength of the iron cores 41 and 42 can be increased. Moreover, the concave grooves 61, 62 can restrict the adhesives 45, 46 applied to the inside thereof from spreading around and can also be used as a guide of the application position, so that the application of the adhesives 45, 46 is easy and easy. It can be performed reliably.

Further, since the surface after the adhesive 46 is cured is roughened in an irregular shape, the unevenness causes the joint end face 42E1 and the joint recess 43 in the case of the first embodiment.
There is a possibility that a slight gap is formed between the iron cores 41 and 42 and the magnetic coupling at the joint between the iron cores 41 and 42 is impaired. However, according to the configuration in which the concave groove 62 is provided in the joint end surface 42E and the adhesive 46 is accommodated and provided therein as described above, the adhesive 46 is prevented from being caught in the joint portion between the iron cores 41 and 42. Can be. Therefore, it is possible to prevent the magnetic coupling at the joint portion from being damaged due to the adhesive 46, and therefore, it is possible to reduce the variation in the characteristics of the discharge lamp ballast 20.

FIGS. 11 to 17 show a third embodiment of the present invention. This embodiment is basically similar to the first embodiment.
Since the configuration is the same as that of the first embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, and the description of the configuration and operation is omitted, and different portions will be described below. The difference between the third embodiment and the first embodiment is the structure of the portion where the adhesives 45 and 46 are provided.

That is, each frame portion 41A of the side leg iron core 41,
A groove 61 extending in the thickness direction of the iron core 41 is formed on the outer surface of the central portion in the longitudinal direction of 41B.
Both ends of the concave groove 61 are closed by outermost iron core plates 41ae located at both ends in the stacking direction.

In order to form the concave groove 61 having such a structure, the first core plates 41a stacked on each other and the outermost first core plates 41a stacked so as to sandwich the first core plates 41a and positioned at both ends in the stacking direction of the side leg iron cores 41. Two types of iron core plates, ie, two iron core plates 41ae, are employed. That is, as shown in FIG. 14, the notch 61a
The recesses 61 are obtained by laminating these iron core plates 41a to connect the notches 61a. As shown in FIG. 13, the second iron core plate 41ae having no notch is used. The adhesive 45 is applied to the inside of the concave groove 61 whose both ends are partitioned by the pair of second iron core plates 41ae as described above so as to extend in the thickness direction of the side leg iron core 41. Core plates 41a, 41ae laminated by the agent 45
The side leg iron core 41 is assembled while maintaining the laminated state.

Similarly, each joint end surface 42 of the center leg iron core 42
A groove 62 extending in the thickness direction of the iron core 42 is formed on each of the distal end surfaces of E1 and each of the leakage convex portions 44, and both ends of the groove 62 are outermost iron cores positioned at both ends in the stacking direction. It is closed by the plate 42ae.

In order to form the concave groove 62 having such a structure, the first iron core plates 42a stacked on each other and the outermost first iron core plates 42a stacked so as to sandwich them are positioned at both ends in the stacking direction of the central leg iron core 42. Two types of iron core plates, ie, two iron core plates 42ae, are employed. That is, as shown in FIG. 16, the notch 62a is formed in the corresponding portion of the first iron core plate 42a.
The recesses 62 are obtained by laminating the iron core plates 42a to connect the notches 62a. As shown in FIG. 15, the second iron core plate 42ae having no notch is used. The adhesive 46 is applied to the inside of the concave groove 62 having both ends partitioned by the pair of second core plates 42ae as described above so as to extend in the thickness direction of the center leg iron core 42, respectively. Core plates 42a, 42 stacked via the agent 46
The center leg iron core 42 is assembled while maintaining the laminated state of ae. In addition,. Structures other than the above are shown in FIGS.
This is the same as the first embodiment, including the configuration not shown in FIG.

In the configuration of the third embodiment,
The laminated state of the plurality of core plates 41a and 41ae is
5 and a plurality of iron core plates 42a, 42a
Since the laminated state of e is held by the adhesive 46, the first problem of the present invention can be solved for the reason already described in the first embodiment. In addition, since the portions where the adhesives 45 and 46 are provided are formed as the concave grooves 61 and 62, a large bonding area can be secured, and accordingly the bonding strength is improved and the two iron cores 41 and 42 are improved.
Can increase the assembling strength. Moreover, the concave groove 6
The adhesives 45, 4 applied to the inside thereof by 1, 62
The adhesives 45 and 46 can be easily and reliably applied since the adhesive 6 can be restricted so as not to spread around and can be used as a guide for the application position.

Further, since the surface after the adhesive 46 is cured is roughened in an irregular shape, the unevenness causes the joint end face 42E1 and the joint recess 43 in the case of the first embodiment.
There is a possibility that a slight gap is formed between the iron cores 41 and 42 and the magnetic coupling at the joint between the iron cores 41 and 42 is impaired. However, according to the configuration in which the concave groove 62 is provided in the joint end surface 42E and the adhesive 46 is accommodated and provided therein as described above, the adhesive 46 is prevented from being caught in the joint portion between the iron cores 41 and 42. Can be. Therefore, it is possible to reduce the possibility that the magnetic coupling at the joining portion is damaged due to the adhesive 46, and therefore, it is possible to reduce the variation in the characteristics of the discharge lamp ballast 20.

Further, in the third embodiment, both iron cores 4
1 and 42 can be easily manufactured. Hereinafter, the side leg iron core 41 will be described as a representative.

That is, two types of iron core plates 41a, 41a
e, when assembling the side leg iron core 41, first, FIG.
As shown in FIG. 7, a plurality of core plates 41a, 41ae corresponding to the plurality of, for example, three side leg cores 41 are sequentially laminated.
In this laminated state, the concave grooves 61 of each iron core 41 are separated by the outermost iron core plates 41ae of the adjacent iron cores 41, and are formed in a row in the stacking direction of the iron cores 41, though discontinuous. Next, by continuously applying the adhesive 45 over the concave grooves 61 arranged in a line as described above, the core plates 41a, 4a of the three side leg cores 41 are simultaneously formed.
1ae is adhered and held in a laminated state. Finally, the three side leg cores 41 held in a laminated state by the bonding are made independent from each other, whereby the three side leg cores 41 can be manufactured at the same time.

Incidentally, in the three side leg cores 41 held in a laminated state by the bonding step, the bonding area is large in the concave groove 61, so that the bonding strength can be ensured to be large. Since the bonding area between the outermost iron core plates 41ae of the side leg iron cores 41 is small, the bonding strength is low. Therefore, when the laminated cores 41 are made independent after the bonding, the difference in the bonding strength is used to easily separate the side leg cores 41 between adjacent outermost core plates 41ae. be able to. In this way, the work of bonding the plurality of side leg cores 41 can be performed at the same time, and the subsequent work of separating each side leg core 41 can be easily performed, so that the productivity of the side leg cores 41 can be improved.

In this situation, both ends of the concave groove 62 are closed by the iron core plates 42ae, and the adhesive 46 is provided in the concave groove 62 to maintain the laminated state by the center leg iron core 42.
The same applies to.

It should be noted that the present invention is not limited to the above-described embodiments, but instead of providing a leakage convex portion on the side surface of the central portion of the central leg iron core 42 in the longitudinal direction, the central leg iron core 42 is not limited thereto.
The air-gap g is provided on the side surface of the side leg 41, and the leaking convex portion 44 which is opposed to and protrudes integrally with the inner surface of the long frame portion 41A of the side leg iron core 41A in the longitudinal direction and passes through the closed magnetic path of the iron core structure 26. The present invention can also be applied to a discharge lamp ballast having a magnetic leakage structure that leaks magnetic flux.

Further, the present invention provides an L-TL-L which is a combination of a pair of L-shaped side leg cores and a T-shaped center leg core disposed between these side leg cores to form a central leg. Device used as a transformer or choke coil having a core-shaped core structure, or a transformer or choke coil provided with an EI-shaped core structure in which an E-shaped core and an I-shaped core are combined with a central leg. , Or an electromagnetic device used as a transformer or a choke coil having an EE type iron core structure formed by combining a pair of E-type iron cores having a central leg, or a T-type having a central leg The present invention can also be applied to a transformer having a T-shaped iron core structure formed by combining an iron core and a U-shaped iron core, an electromagnetic device used as a choke coil, and the like.

[0058]

The present invention is embodied in the form described above and has the following effects.

According to the first aspect of the present invention, since the laminated core plates are adhered to each other with the adhesive extending in the thickness direction of the core, the laminated state of the core plates can be reliably maintained. With the superimposed structure of the laminated state, welding traces are not provided on the iron core and the magnetic resistance of the magnetic path of the iron core structure does not increase, and iron loss at the iron core can be reduced,
Power efficiency can be improved.

According to the second aspect of the invention, which is dependent on the first aspect of the invention, in addition to the effect of the first aspect of the invention, a large bonding area is secured by the concave groove provided with the adhesive.
The performance of holding the iron core plates in a stacked state can be improved.

According to the third aspect of the invention, which is dependent on the second aspect, in addition to the effect of the second aspect, a portion where the plurality of iron cores are laminated and each of the iron cores has a concave groove is provided. In order to make each iron core laminated independently after applying adhesive continuously, the strength difference between the adhesive in the groove and the adhesive between the adjacent outermost iron core plates is used. hand,
Since the laminated cores can be easily separated at the boundary between the adjacent outermost core plates, a plurality of cores can be bonded at the same time and the separation is easy, thereby improving the manufacturability. be able to.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a configuration of a transformer main body of a discharge lamp ballast according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing the configuration of the transformer main body shown in FIG. 1;

FIG. 3 is an exploded perspective view showing a configuration of an iron core structure of the transformer main body shown in FIG. 1;

FIG. 4 is a plan view showing the configuration of the iron core structure shown in FIG. 3;

FIG. 5 is a perspective view showing the configuration of the entire discharge lamp ballast according to the first embodiment.

FIG. 6 is a diagram for explaining an eddy current generated in a center leg iron core included in the transformer main body shown in FIG. 1;

FIG. 7 is an exploded perspective view showing a configuration of an iron core structure provided in a discharge lamp ballast according to a second embodiment of the present invention.

FIG. 8 is a plan view showing the configuration of the iron core structure shown in FIG. 7;

9 is a plan view showing a configuration of a core plate for a side leg iron core included in the iron core structure shown in FIG. 7;

FIG. 10 is a plan view showing a configuration of a core plate for a center leg iron core included in the iron core structure shown in FIG. 7;

FIG. 11 is an exploded perspective view showing a configuration of an iron core structure provided in a discharge lamp ballast according to a third embodiment of the present invention.

FIG. 12 is a plan view showing the configuration of the iron core structure shown in FIG. 11;

FIG. 13 is a plan view showing a configuration of a first core plate for a side leg iron core provided in the iron core structure shown in FIG. 11;

FIG. 14 is a plan view showing a configuration of a second core plate for a side leg iron core included in the iron core structure shown in FIG. 11;

FIG. 15 is a plan view showing a configuration of a first iron core plate for a center leg iron core included in the iron core structure shown in FIG. 11;

FIG. 16 is a plan view showing a configuration of a second core plate for a center leg iron core included in the iron core structure shown in FIG. 11;

17 is a perspective view showing a state in which a plurality of side leg iron cores included in the iron core structure shown in FIG. 12 are stacked;

FIG. 18 is an exploded perspective view showing a configuration of an iron core structure provided in a discharge lamp ballast according to a first conventional example.

FIG. 19 is a plan view showing a configuration of an iron core structure provided in a discharge lamp ballast according to a first conventional example.

FIG. 20 is an exploded perspective view showing a configuration of an iron core structure provided in a discharge lamp ballast according to a second conventional example.

FIG. 21 is a diagram for explaining an eddy current generated in a center leg iron core included in an iron core structure provided in a discharge lamp ballast according to a second conventional example.

[Explanation of symbols]

 Reference Signs List 20: discharge lamp stabilizer (electromagnetic device), 21: transformer body (electromagnetic device body), 25: coil, 26: iron core structure, 27, 28: coil bobbin, 29, 30 ... conductor, 41: side leg iron core, 41a ... side core plate of side leg core, 41ae ... outermost core plate of side leg core, 42 ... center leg core, 42a ... core plate of center leg core, 42ae ... outermost core plate of center leg core, 45, 46 ... adhesive, 61, 62 ... concave grooves.

Claims (3)

[Claims] An iron core structure formed by laminating a plurality of iron core plates and maintaining the stacked state, a core wound around a coil bobbin and having a conductor wound around a coil bobbin. And at least one coil combined with the iron core structure by fitting the coil bobbin to the iron core structure. An adhesive provided by extending the stacked iron core plates in the thickness direction of the iron core is provided. An electromagnetic device wherein the laminated state of the iron core plates is maintained by bonding. 2. The electromagnetic device according to claim 1, wherein a concave groove extending in a thickness direction of the core is formed in the iron core, and the adhesive is provided in the concave groove. 3. The electromagnetic device according to claim 2, wherein both ends of the concave groove are covered with outermost iron core plates located at both ends in the stacking direction of the iron core.