JP2011014755A - Coil component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coil component capable of securely reducing generation of noise due to a gap of a core half.SOLUTION: The coil component 1 includes a pair of core halves 2a, 2b, whose inner magnetic legs 3a, 3b are inserted into a cylinder of a bobbin 5 having a winding around an outer circumferential part. The inner magnetic legs 3a, 3b are disposed opposite each other and have an adhesive tape 11a stuck on a facing surface 30a and side walls 31a of the inner magnetic leg 3a interposing the facing surface 30a and positioned on both sides thereof and also have an adhesive tape 11b stuck on a facing surface 30b and side walls 31b of the inner magnetic leg 3b interposing teh facing surface 30b and positioned on both sides thereof. Then a cylinder inner wall of the bobbin 5, and the side walls 31a and 31b of the inner magnetic legs 3a and 3b are bonded together with an impregnant 9.

Description

  The present invention relates to a coil component comprising a bobbin and a core wound with a winding, and more particularly to a coil component in which a gap is formed between opposing magnetic legs.

  Conventionally, various coil components such as a choke coil and a transformer have been used in accordance with applications and required characteristics. For example, the coil component 10 shown in FIG. 6 includes a cylindrical bobbin 5 around which a winding 6 is wound around an outer peripheral portion, and a core 2. The pair of core halves 2a and 2b constituting the core 2 are the same, and the cross-sectional shape is E-shaped. That is, the core half 2a (2b) includes two outer magnetic legs 4a (4b) and one middle magnetic leg 3a (3b) disposed therebetween. The core halves 2a and 2b are arranged so as to face each other so that the middle magnetic legs 3a and 3b and the outer magnetic legs 4a and 4b abut each other.

  In the coil component 10 shown in FIG. 6, the gap 7 is formed by sandwiching the spacer 8 between the middle magnetic legs 3a and 3b and between the outer magnetic legs 4a and 4b. Thereby, magnetic saturation of the core 2 is prevented. The gap 7 may be formed only between the middle magnetic legs 3a and 3b.

  By the way, the coil component in which the gap is formed sometimes generates a beat sound (hereinafter referred to as “abnormal noise”) due to the vibration of the magnetic leg during driving. Therefore, a technique has been proposed in which the magnetic legs of a pair of core halves are joined with an adhesive to suppress the vibration of the core halves and prevent the generation of abnormal noise (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 2004-200336

  As a method of joining the magnetic legs of the pair of core halves, for example, a method of immersing the coil component 10 shown in FIG. 6 in a dip tank storing the impregnating agent 9 is simple. As the impregnating agent 9, for example, varnish is used. Thus, according to the coil component 10 ′ impregnated with the impregnating agent 9, the core halves 2a (2b) and the bobbin 5 are joined together by the impregnating agent 9, and the vibration of the core half 2a (2b) is suppressed. The generation of abnormal noise can be reduced (FIG. 7).

  However, such a coil component 10 'has a narrow gap between the middle magnetic legs 3a, 3b and the bobbin 5, and the core half 2a (2b) and the tolerance in manufacturing the bobbin 5 and the core half 2a (2b during impregnation) ) And the position of the bobbin 5 may be insufficiently penetrated by the impregnating agent 9 into the bobbin 5 (FIG. 8). As a result, the degree of adhesion between the core halves 2a (2b) and between the core halves 2a (2b) and the bobbin 5 is weakened, and it may be impossible to reduce the occurrence of abnormal noise.

  Here, it is possible to try to improve the insufficient permeation of the impregnating agent 9 such as extending the impregnation time of the impregnating agent 9. However, since it is difficult to manage the deviation of the position of the core half 2a (2b) and the bobbin 5 at the time of impregnation, it is substantially possible to suppress individual differences between coil parts with respect to the degree of adhesion by the impregnating agent 9, Impossible. As a result, as shown in FIG. 8, the bobbin 5 is biased with respect to the core half 2a (2b), which is a cause of abnormal noise. For this reason, the coil component which can reduce generation | occurrence | production of abnormal noise reliably was desired.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a coil component that can reliably reduce the generation of abnormal noise caused by the gap in the core half.

  The present invention includes a first bobbin having a cylindrical bobbin having a winding wound around an outer peripheral portion, and a middle magnetic leg that extends in the cylinder axis direction of the bobbin and is inserted into the cylinder of the bobbin. And a second core half disposed opposite to the middle magnetic leg with a predetermined gap, and an adhesive tape material affixed to the middle magnetic leg, and impregnated with the inner wall of the bobbin and the side wall of the middle magnetic leg The adhesive tape material is bonded to the first main surface and the both sides of the first main surface when the surface of the middle magnetic leg facing the second core half is the first main surface. It is characterized by being affixed to the side wall of the middle magnetic leg located in

  According to the invention configured as described above, the adhesive tape material is formed on the first main surface facing the second core half of the middle magnetic legs and on both sides of the first main surface. Affixed to the side wall of the leg. For this reason, the tape material part affixed on the 1st main surface functions as a spacer, and it becomes unnecessary to insert a spacer separately. In addition, the tape material part affixed to the side walls of the middle magnetic legs located on both sides of the first main surface prevents the bias of the position of the first core half with respect to the bobbin, and the bobbin has a good impregnating agent. Can be spread over. For this reason, the individual difference between coil components with respect to the adhesion degree of an impregnating agent can be suppressed, and generation | occurrence | production of the noise of a coil component can be reduced reliably.

  Here, it is preferable that the adhesive tape material is affixed to the side wall over the whole extending direction of the middle magnetic leg. According to this configuration, it is possible to reliably prevent the middle magnetic leg from being inclined with respect to the bobbin in the extending direction of the middle magnetic leg (in the cylinder axis direction of the bobbin), and to improve the impregnation property of the impregnating agent inside the bobbin.

  Moreover, you may comprise an adhesive tape material with the 1st tape affixed on the 1st main surface in the predetermined direction, and the 2nd tape affixed on the direction orthogonal to a 1st tape. According to this configuration, it is possible to effectively prevent the occurrence of a positional deviation in the radial direction of the first core half with respect to the bobbin.

  Further, in the coil component including the second intermediate surface that has the second main surface that is inserted into the bobbin cylinder and is opposed to the first main surface, the second core half is disposed on the opposite side intermediate magnetic leg. The opposite-side adhesive tape is further provided, and the inner wall of the bobbin cylinder and the side wall of the opposite-side middle magnetic leg are bonded via an impregnating agent, and the opposite-side adhesive tape is formed on the second main surface and the second main surface. It is preferable that it is affixed to the side wall of the opposite side magnetic leg located on both sides of the sheet.

  According to this structure, the adhesive tape affixed on the 1st main surface and the opposing side adhesive tape affixed on the 2nd main surface function as a spacer, and it becomes unnecessary to insert a spacer separately. Moreover, the adhesive tape affixed to the side walls of the middle magnetic legs located on both sides of the first main surface and the opposite side affixed to the side walls of the opposing side magnetic magnetic legs located on both sides of the second main surface Each of the side adhesive tapes can prevent the position of the first core half and the second core half with respect to the bobbin from being biased, and can satisfactorily spread the impregnating agent inside the bobbin. For this reason, the individual difference between coil components with respect to the adhesion degree of an impregnating agent can be suppressed, and generation | occurrence | production of the noise of a coil component can be reduced reliably.

  Here, it is preferable that the opposing side adhesive tape material is stuck to the side wall over the whole extending direction of the opposing side magnetic leg. According to this configuration, it is possible to reliably prevent the occurrence of an inclination of the opposing side magnetic leg with respect to the bobbin in the extending direction of the opposing side magnetic leg (in the cylinder axis direction of the bobbin), and improve the impregnation property of the impregnating agent inside the bobbin. be able to.

  Further, the opposing side adhesive tape material is constituted by a first opposing side tape attached in a predetermined direction on the second main surface and a second opposing side tape attached in a direction orthogonal to the first opposing side tape. May be. According to this configuration, it is possible to effectively prevent the deviation of the position in the radial direction of the second core half with respect to the bobbin.

  According to the present invention, it is possible to suppress individual differences between coil parts with respect to the degree of adhesion of the impregnating agent, and reliably reduce the occurrence of abnormal noise caused by the gap of the core half.

It is sectional drawing which shows one Embodiment of the coil components of this invention. It is a perspective view of the core used for the coil component of this invention. It is a perspective view of a core in the state where an adhesive tape was stuck. It is a perspective view of a core in the state where an adhesive tape was stuck. It is sectional drawing which shows the deformation | transformation form of the coil components of this invention. It is sectional drawing which shows the conventional coil components. It is sectional drawing which shows the conventional coil components. It is sectional drawing which shows the conventional coil components.

  FIG. 1 is a cross-sectional view showing an embodiment of a coil component of the present invention. FIG. 2 is a perspective view of a core used for the coil component of the present invention. The coil component 1 includes a cylindrical bobbin 5 around which a winding 6 is wound around an outer peripheral portion, and an EER-type core 2. The pair of core halves 2a and 2b constituting the core 2 are the same, and the cross-sectional shape is E-shaped. That is, the core half 2a (2b) includes two outer magnetic legs 4a (4b) and one middle magnetic leg 3a (3b) disposed therebetween. The core halves 2a and 2b are arranged such that the middle magnetic legs 3a and 3b and the outer magnetic legs 4a and 4b face each other.

  The middle magnetic legs 3 a and 3 b extend in the cylinder axis direction of the bobbin 5 and are inserted into the cylinder of the bobbin 5. Between the middle magnetic legs 3a and 3b and between the outer magnetic legs 4a and 4b, a gap 7 with a predetermined interval is formed in order to prevent magnetic saturation and improve DC superposition characteristics. The gap 7 is formed by sandwiching the spacer 8 between the outer magnetic legs 4a and 4b.

  Referring to FIG. 1, in coil component 1, adhesive tapes 11 a and 11 b are attached to both middle magnetic legs 3 a and 3 b from the side walls through opposing surfaces 30 a and 30 b toward the opposite side walls, respectively. . That is, each of the middle magnetic legs 3a and 3b has opposing faces 30a and 30b arranged so as to face each other, and the adhesive tape 11a is located on the opposing face 30a and on both sides of the opposing face 30a. The adhesive tape 11b is attached to the side wall 31b of the middle magnetic leg 3b located on both sides of the opposing surface 30b and the opposing surface 30b. The adhesive tapes 11a and 11b function as a spacer 8 between the middle magnetic legs 3a and 3b.

  According to this configuration, the middle magnetic legs 3a and 3b are stably positioned near the center of the bobbin 5 inside the cylinder. Thus, in this embodiment, one of the core halves 2a and 2b functions as the “first core half” of the present invention, and the other functions as the “second core half” of the present invention. When the core half 2a functions as the “first core half” of the present invention and the core half 2b functions as the “second core half” of the present invention, the facing surface 30a of the middle magnetic leg 3a is the present invention. On the other hand, the facing surface 30b of the middle magnetic leg 3b corresponds to the “second main surface” of the present invention. Further, the middle magnetic leg 3b corresponds to the “opposite side magnetic leg” of the present invention, and the adhesive tape 11b corresponds to the “opposite side adhesive tape” of the present invention.

  The coil component 1 is immersed in a dip tank in which an impregnating agent 9 such as varnish is stored, so that the inner wall of the bobbin 5 and the side walls 31a and 31b of the middle magnetic legs 3a and 3b are bonded via the impregnating agent 9. ing. The adhesive tapes 11a and 11b are wound around a tape material used in other parts of the coil component, for example, an exterior tape that fixes the core halves 2a and 2b from the outside, or the outer periphery of the bobbin 5. By diverting the same tape material, such as interlayer tape, used for the purpose of separating the distance between the winding 6 and the surrounding parts (other windings, cores, etc.), the price of the parts can be reduced. It is also desirable because it is a material that has been certified for safety. As such a tape material, for example, an insulating tape made of a polyester film or a support made of a polyester film and a polyester nonwoven fabric and an acrylic pressure-sensitive adhesive can be used.

  FIG. 3 is a perspective view of the core in a state where an adhesive tape is attached. As shown in FIG. 3, the adhesive tape material 11a (11b) is preferably attached to the side wall 31a (31b) over the entire extending direction of the middle magnetic leg 3a (3b) (the cylindrical axis direction of the bobbin 5). . Thereby, the tilting of the middle magnetic leg 3a (3b) with respect to the bobbin 5 in the extending direction of the middle magnetic leg 3a (3b) can be reliably prevented, and the impregnation of the impregnating agent 9 into the bobbin 5 can be improved. .

  Further, the adhesive tape may be applied in two directions as shown in FIG. 4 in addition to the case where the adhesive tape is applied in one direction on the facing surface 30a (30b) of the middle magnetic leg 3a (3b). . Specifically, on the facing surface 30a, the adhesive tape 11a (corresponding to the “first tape” of the present invention) and the adhesive tape 12a (corresponding to the “second tape” of the present invention) in the direction orthogonal to the adhesive tape 11a. ) May be pasted. Further, on the opposing surface 30b, the adhesive tape 11b (corresponding to the “first opposing tape” of the present invention) and the adhesive tape 12b (corresponding to the “second opposing tape” of the present invention) in a direction orthogonal to the adhesive tape 11b are used. Equivalent) may be pasted. Thus, the middle magnetic legs 3a and 3b are positioned more stably near the center inside the cylinder of the bobbin 5 than when the adhesive tape is applied in one direction by applying the adhesive tape in two directions. In this case, the adhesive tape 11a and the adhesive tape 12a constitute the “adhesive tape material” of the present invention, and the adhesive tape 11b and the adhesive tape 12b constitute the “opposite side adhesive tape material” of the present invention.

  As described above, according to this embodiment, in the coil component 1, the middle magnetic legs 3a and 3b are stably positioned near the center inside the cylinder of the bobbin 5 by the adhesive tapes 11a and 11b. The deviation of the position of the core half 2a (2b) with respect to the bobbin 5 can be suppressed. For this reason, the individual difference between coil parts with respect to the adhesion degree of the impregnating agent 9 can be suppressed, and generation | occurrence | production of the noise of a coil part can be reduced reliably.

<Example>
2000 coil parts according to the example and 2000 coil parts according to the conventional example were produced, and abnormal noise during driving was measured for each coil part. The measurement results (average abnormal noise) are shown in Table 1. In the coil component according to the embodiment, the adhesive tape is attached to one core half in one direction, and the two adhesive tapes are attached to the other core half in two directions orthogonal to each other. .

  In the coil component 10 ′ according to the conventional example, as shown in FIG. 7, there is no adhesive tape on the middle magnetic legs 3 a and 3 b, and the gap 7 is formed by the spacer 8. Other components, for example, core dimensions, gap dimensions, and the like are all the same as those of the coil component 1 according to the embodiment.

  The abnormal noise during driving is evaluated by measuring the abnormal noise emitted from the coil components with a noise meter (NL-22 manufactured by Rion Co., Ltd.) when each coil component is used as a converter transformer in the switching power supply circuit. went. The measurement frequency range of the used sound level meter was 20 to 8 k [Hz], and the sound level meter was directly brought into contact with the core for measurement. In the measurement results shown in Table 1, the amount of change from the reference value is described with the conventional noise as a reference (0 [dB]).

  As is clear from the results in Table 1, in the coil component according to the example, abnormal noise (average abnormal noise) is greatly improved as compared with the coil component according to the conventional example. That is, in the coil component according to the example, it has been clarified that the individual difference between the coil components with respect to the degree of adhesion of the impregnating agent is suppressed, and the occurrence of abnormal noise of the coil component can be reduced.

<Others>
The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the above embodiment (FIG. 1), an “EER core” formed by combining core halves having an E-shaped cross section is used, but the present invention is not limited to this, and a core having another shape is used. It can also be applied to coil parts. Applicable cores include, for example, an “EI core” (see FIG. 5) formed by combining an E-shaped core half 2a and an I-shaped core half 2c, and a “PQ core”.

  FIG. 5 is a cross-sectional view showing a modified form of the coil component of the present invention. In this case, in the coil component 1A, a gap 7 is formed between the middle magnetic leg 3a of the E-shaped core half 2a and the I-shaped core half 2c. And the adhesive tape 11 is affixed on the opposing surface 30a which opposes the core half 2c, and the side wall 31a of the intermediate | middle magnetic leg 3a located in the both sides on both sides of this opposing surface 30a. The Even in this configuration, in the coil component 1A, the middle magnetic leg 3a is stably positioned near the center inside the cylinder of the bobbin 5 by the adhesive tape 11, and the position of the core half 2a relative to the bobbin 5 at the time of impregnation is offset. Can be suppressed. For this reason, the individual difference between coil parts with respect to the adhesion degree of the impregnating agent 9 can be suppressed, and generation | occurrence | production of the noise of a coil part can be reduced reliably.

  The coil component of the present invention can be applied to various electronic components formed by winding a winding around a core, such as a converter transformer according to an embodiment, a choke coil, and the like.

DESCRIPTION OF SYMBOLS 1, 1A, 10, 10 '... Coil components 2 ... Core 2a, 2b, 2c ... Core half 3a, 3b ... Middle magnetic leg 4a, 4b ... Outer magnetic leg 5 ... Bobbin 6 ... Winding 7 ... Gap 8 ... Spacer 9 ... Impregnating agent 11, 11a, 11b, 12a, 12b ... Adhesive tape

Claims (6)

A cylindrical bobbin with a winding wound around the outer periphery;
A first core half extending in the cylinder axis direction of the bobbin and having a middle magnetic leg inserted into the bobbin cylinder;
A second core half disposed opposite to the middle leg with a predetermined gap;
With an adhesive tape material to be affixed to the middle magnetic leg,
The inner wall of the bobbin cylinder and the side wall of the middle magnetic leg are bonded via an impregnating agent,
When the surface where the middle magnetic leg faces the second core half is the first main surface, the adhesive tape material is located on the first main surface and on both sides of the first main surface. A coil component attached to a side wall of the middle magnetic leg.   The coil component according to claim 1, wherein the adhesive tape material is affixed to the side wall over the entire extending direction of the middle magnetic leg.   The said adhesive tape material consists of the 1st tape stuck in the predetermined direction on the said 1st main surface, and the 2nd tape stuck in the direction orthogonal to the said 1st tape. Coil parts. The said 2nd core half body was provided in the cylinder side of the said bobbin, and was equipped with the opposing side middle magnetic leg which has a 2nd main surface facing the said 1st main surface. Coil components,
Further comprising an opposing side adhesive tape affixed to the opposing side magnetic leg,
The cylindrical inner wall of the bobbin and the side wall of the opposed middle magnetic leg are bonded via the impregnating agent,
The coil component, wherein the opposing adhesive tape is affixed to a side wall of the opposing intermediate magnetic leg located on both sides of the second main surface and the second main surface.   The coil component according to claim 4, wherein the facing-side adhesive tape material is affixed to the side wall over the entire extending direction of the facing-side middle magnetic leg.   On the second main surface, the opposing adhesive tape material is composed of a first opposing tape attached in a predetermined direction and a second opposing tape attached in a direction orthogonal to the first opposing tape. The coil component according to claim 4 or 5.

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