JP5157956B2 - Reactor - Google Patents

Description

  The present invention relates to a reactor that easily suppresses vibration and noise.

  Conventionally, a reactor 90 having a structure shown in FIG. 12 is known. The reactor 90 is obtained by embedding a coil 92 and a core member 93 in a core 91 made of a magnetic powder mixed resin in which a magnetic powder is dispersed in a resin. Since a coil 92 and a core 91 generate heat when an electric current is passed, a core member 93 is inserted in order to improve heat dissipation.

  On the other hand, it is known that the coil 92 and the core 91 vibrate due to the magnetic field generated in the reactor 90 when an alternating current is passed through the coil 92. In order to suppress this vibration, a urethane resin 95 or the like is interposed between the case 94 and the core 91.

  When manufacturing the reactor 90, first, a member in which the core 91, the coil 92, and the core member 93 are integrated is formed. A liquid urethane resin 95 is stored in the case 94, and a member in which the core 91 and the like are integrated is stored in the case 94. Thereby, the liquid urethane resin 95 can be filled in the gap between the case 94 and the core 91.

JP 2008-198981 A

However, when the above manufacturing method is used, as shown in FIG. 13, when the core 91 is strongly pressed, the bottom surface 91a of the core 91 and the bottom surface 94a of the case 94 come into contact with each other, and a thin film of the urethane resin 95 may not be formed. is there.
In this case, when the coil 92 and the core 91 vibrate with energization, there is a problem that the vibration is transmitted to the bottom surface of the case 94 and noise is generated. Therefore, there is a demand for a reactor that can form a thin film of urethane resin (damping material) with a certain thickness between the bottom of the case and the bottom of the core, and that is less susceptible to vibration and noise.

  The present invention has been made in view of such conventional problems, and provides a reactor in which a thin film of a damping material can be formed between the bottom surface of the case and the bottom surface of the core with a constant thickness and is less likely to generate vibration and noise. It is something to try.

The first invention comprises a core made of a magnetic powder mixed resin in which a magnetic powder is dispersed in a resin;
A coil embedded in the core and generating magnetic flux when energized;
A core member that is positioned inside the coil and is formed in a columnar shape facing the axial direction of the coil, and is embedded in the core with at least one end face in the axial direction exposed from the bottom surface of the core When,
A storage case for storing the core together with the coil and the core member;
The case bottom surface of the storage case and the end surface of the core member are in direct or indirect contact with each other, and a bottom side gap is provided between the case bottom surface and the core bottom surface on the outer peripheral side of the contact portion. A side-side gap is provided between the inner peripheral surface of the storage case and the outer peripheral surface of the core, and the bottom-side gap and the side-side gap are located more than the core. It is filled with a damping material made of a material with a small Young's modulus ,
The case bottom surface is in a reactor characterized in that the contact portion projects from the outer peripheral portion toward the core member (claim 1).

Next, the effects of the present invention will be described.
In the present invention, the case bottom face and the end face of the core member are in contact with each other, and a bottom face side gap is formed between the case bottom face and the core bottom face on the outer peripheral side of the contact portion. The bottom gap was filled with a vibration damping material.
If it does in this way, the thickness of a damping material can be kept constant. That is, when manufacturing the reactor, first, a member in which the core, the core member, and the coil are integrated is manufactured. And a liquid damping material is stored in a storage case, and the said member is stored in the storage case. At this time, since the end surface of the core member is in contact with the case bottom surface, the core bottom surface and the case bottom surface are not in contact with each other, and the thickness of the damping material interposed therebetween can be kept constant. Thereby, the vibration of the coil and the core can be absorbed by the damping material, and noise and the like are easily suppressed.
In addition, when the reactor is manufactured, if the above member is put into the storage case with a strong force so that the end surface of the core member is always in contact with the contact portion of the bottom surface of the case, the vibration damping material becomes thicker than necessary. Can be prevented. If the damping material becomes too thick, problems such as a decrease in heat dissipation tend to occur.
In this example, since the damping material is also filled in the side surface side gap, it is possible to prevent the vibration of the coil or the like from being transmitted to the side surface of the case. Therefore, noise can be effectively suppressed.

  As described above, according to the present invention, a thin film of a damping material can be formed between the bottom surface of the case and the bottom surface of the core with a constant thickness, and a reactor that is unlikely to generate vibration and noise can be provided.

The perspective view of the reactor in Example 1. FIG. Sectional drawing of the reactor in Example 1. FIG. The principal part enlarged view of FIG. The manufacturing process explanatory drawing of the reactor in Example 1. FIG. The figure following FIG. The figure following FIG. The figure following FIG. The principal part enlarged view of the reactor which made the center core member protrude in the reference example 1. FIG. Sectional drawing at the time of making both a bottom face and a core member protrude in Example 1. FIG. Sectional drawing at the time of interposing the member for raising a bottom in the reference example 2. FIG. The example of the circuit which used the reactor in Example 1. FIG. Sectional drawing of the reactor in a prior art example. It is sectional drawing of the reactor in a prior art example, Comprising: Explanatory drawing of the state by which the damping material is not formed in the bottom part.

A preferred embodiment of the present invention described above will be described.
In the present invention, the bottom of the case, said contact sites than the outer peripheral side thereof that is configured to protrude into the central core member.
Therefore, since the abutting portion is formed so as to protrude, when the member in which the core, the coil, and the core member are integrated is put in the storage case, the end surface of the core member contacts the abutting portion. In contact therewith, a bottom side gap is reliably formed on the outer peripheral side. Moreover, if the protrusion height of the contact part is determined in advance, the thickness of the damping material will not be thinner than that height.

Moreover, it is preferable that the edge part of the said core member protrudes from the said core bottom face, and this edge part is contacting the said case bottom face (Claim 2 ).
In this way, since the end portion of the central core member is protruded from the core bottom, can that form the bottom side gap. Further, if the protruding height of the end portion is determined in advance, the thickness of the damping material will not be thinner than that height.

Further, the storage case has a core fixing projection at the bottom of the storage case, the core member has a recess that fits into the projection, and the outer surface of the projection and the recess between the inner surface, it is preferable that the damping material is filled (claim 3).
If it does in this way, a core can be fixed to a storage case with the above-mentioned projection. Further, a damping material is filled between the outer surface of the protrusion and the inner surface of the recess. Damping material (urethane resin, etc.) has a higher thermal conductivity than air. Therefore, with the above structure, the damping material is not filled and heat is the core member compared to the case where there is an air layer. It becomes easy to be transmitted from the storage case. Therefore, heat dissipation can be improved.

In addition, the protruding portion includes a trunk portion protruding from the bottom of the storage case, and a reduced diameter portion provided on the distal end side of the trunk portion and having a smaller outer diameter than the trunk portion, It is formed in a stepped shape that fits to each of the backbone portion and the reduced diameter portion, and the gap between the reduced diameter portion and the core member is narrower than the gap between the backbone portion and the core member. (Claim 4 ).
In this case, since the gap between the reduced diameter portion and the core member is narrow, the member in which the core, the core member, and the coil are integrated is fixed at an accurate position with respect to the storage case. can do. Thereby, the side surface side gap mentioned above can be controlled accurately, and the thickness of the damping material on the side surface can be easily controlled. If the damping material is too thin, noise will be transmitted easily, and if it is too thick, the heat dissipation will decrease.However, with the above configuration, the thickness of the damping material can be controlled, and the noise suppression effect and heat dissipation You will be able to demonstrate both.

  Moreover, it is preferable to use the reactor of this invention for the power converter circuit for vehicles. Since the power conversion circuit for a vehicle passes a large current, the amplitude of the vibration of the coil is large. In addition, there is a strict requirement for quietness so that noise is not transmitted to vehicle occupants. Therefore, when the reactor of this invention is used for the power converter circuit for vehicles, the effect acquired is especially large.

  On the other hand, the bottom side gap is preferably 0.5 to 2.0 mm. Moreover, it is preferable that a side surface side gap is 0.5-2.0 mm. If the bottom surface side gap is less than 0.5 mm or the side surface side gap is less than 0.5 mm, the vibration damping material becomes too thin, and vibration may not be sufficiently absorbed. On the other hand, if the gap on the bottom side exceeds 2.0 mm or the gap on the side side exceeds 2.0 mm, the damping material becomes too thick, and the heat of the core may be difficult to be transmitted to the storage case.

Example 1
A reactor according to an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is an exploded perspective view of a reactor 1 according to this example, and FIG. 2 is a cross-sectional view. FIG. 3 is an enlarged view of a main part of FIG.
As shown in FIGS. 1 and 2, the reactor 1 of this example includes a core 2 made of a magnetic powder mixed resin in which a magnetic powder is dispersed in a resin.
A coil 3 that generates magnetic flux when energized is embedded in the core 2.
As shown in FIG. 2, it is located inside the coil 3, is formed in a column shape facing the axial direction of the coil 3, and at least one end surface 41 in the axial direction is exposed from the bottom surface 20 of the core 2. A core member 4 embedded in the core 2 is provided.
Further, a storage case 5 for storing the core 2 together with the coil 3 and the core member 4 is provided.
As shown in FIGS. 2 and 3, the case bottom surface 50 of the storage case 5 and the end surface 41 of the core member 4 are in direct contact with each other. A bottom surface side gap 10 is provided between the case bottom surface 50 and the core bottom surface 20 on the outer peripheral side of the contact portion 51. A side surface side gap 11 (see FIG. 2) is provided between the inner peripheral surface 52 of the storage case 5 and the outer peripheral surface 21 of the core 2. The bottom gap 10 and the side gap 11 are filled with a damping material 6 made of a material having a Young's modulus smaller than that of the core 2.
The details will be described below.

  The reactor 1 of this example is used for a power conversion circuit for a vehicle. The core 2 is made by dispersing a magnetic powder such as iron powder in a thermosetting resin such as an epoxy resin. The coil 3 is formed by winding a copper wire, and the storage case 5 and the core member 4 are made of an aluminum alloy. Further, the damping material 6 is made of urethane resin.

  As shown in FIG. 3, the case bottom surface 50 is configured such that the contact portion 51 protrudes from the outer peripheral side. The end surface 41 of the core member 4 is in contact with the contact portion 51.

  As shown in FIG. 7, the storage case 5 has a core fixing projection 7 at the bottom of the storage case 5, and the core member 4 has a recess 40 that fits into the projection 7. As shown in FIG. 2, the damping material 6 is filled between the outer surface 7 a of the protrusion 7 and the inner surface 40 a of the recess 40.

  Further, as shown in FIG. 7, the protruding portion 7 includes a trunk portion 70 that protrudes from the bottom of the storage case 5, and a reduced diameter portion 71 that is provided on the distal end side of the trunk portion 70 and has an outer diameter smaller than that of the trunk portion 70. It has. The recess 40 is formed in a stepped shape that fits into the core portion 70 and the reduced diameter portion 71, and the gap d <b> 1 (see FIG. 2) between the reduced diameter portion 71 and the core member 4 is defined between the core portion 70 and the core portion. It is narrower than the gap d2 with the member 4.

Next, the manufacturing method of the reactor 1 of this example is demonstrated. As shown in FIG. 4, first, the core member 4 and the coil 3 are housed in a molding die 8 (different from the housing case 5). Thereafter, as shown in FIG. 5, the liquid core 2 is poured into the mold 8. The core 2 is obtained by dispersing iron powder or the like in a thermosetting resin as described above, and is in a liquid state before being cured.
Thereafter, when heat treatment is performed at a predetermined temperature, the thermosetting resin is cured, and a member 15 in which the core member 4, the coil 3, and the core 2 are integrated is formed as shown in FIG. The member 15 is taken out from the mold 8.

  Next, as shown in FIG. 7, a predetermined amount of liquid damping material 6 is stored in the storage case 5. The damping material 6 is mainly composed of a urethane resin as described above, and can be heated to be liquid. When the member 15 is stored in this state, the end surface 41 of the core member 4 comes into contact with the contact portion 51 of the storage case 5. Here, since the contact part 51 protrudes from the outer peripheral side, the bottom face side gap 10 (see FIG. 2) is formed between the core bottom face 20 and the case bottom face 50. The bottom surface side gap 10 and the side surface side gap 11 are filled with a liquid damping material 6. Thereafter, the vibration damping material 6 is solidified by cooling.

  As described above, the projecting portion 7 includes the basic portion 70 and the reduced diameter portion 71, and the gap d2 (see FIG. 2) between the basic portion 70 and the core member 4 is relatively wide, and the reduced diameter portion. A gap d1 between 71 and the core member 4 is narrow. More specifically, the gap d1 between the reduced diameter portion 71 and the core member 4 is almost zero. Therefore, the concave portion 40 does not enter the reduced diameter portion 71 unless a strong force is applied.

  In addition, after the member 15 is stored in the storage case 5, the bolt 80 is screwed into the female screw portion 43 to fix the member 15 to the storage case 5.

Further, as shown in FIG. 9, the contact portion 51 of the storage case 5 is protruded from the outer peripheral side, and the end portion 42 of the core member 4 is configured to protrude from the core bottom surface 20. You can also.

  Next, an example of a circuit using the reactor 1 of this example is shown in FIG. Reactor 1 is used in a power conversion circuit 82 for a vehicle. The power conversion circuit 82 includes an inverter unit 81 and a converter unit 83. The inverter unit 81 is composed of a plurality of semiconductor modules 85 as shown in the figure. Each semiconductor module 85 includes an IGBT element 85a and a flywheel diode 85b. Further, the reactor 1 is used in the converter unit 83. The converter unit 83 is used to boost the voltage of the DC power supply 84, and the boosted voltage is applied between the DC input terminals 88 a and 88 b of the inverter unit 81. An alternating voltage can be output from the output terminal 87 by switching the IGBT element 85a. Using this AC voltage, the three-phase AC motor 86 is driven to run the vehicle.

Next, the effect of the reactor 1 of this example is demonstrated.
In this example, as shown in FIGS. 2 and 3, the case bottom surface 50 and the end surface 41 of the core member 4 are in contact with each other, and the outer peripheral side of the contact portion 51 is between the case bottom surface 50 and the core bottom surface 20. A bottom side gap 10 was formed. And the damping material 6 was filled in this bottom face side gap 10.
In this way, the thickness of the damping material 6 can be kept constant. That is, when manufacturing the reactor 1, as shown in FIGS. 4 to 6, first, the member 15 in which the core 2, the core member 4, and the coil 3 are integrated is manufactured. Then, as shown in FIG. 7, the liquid damping material 6 is stored in the storage case 5, and the member 15 is stored in the storage case 5. At this time, since the end surface 41 of the core member 4 contacts the contact portion 51 of the case bottom surface 50, the core bottom surface 20 and the case bottom surface 50 do not contact each other, and the thickness of the damping material 6 interposed therebetween Can be kept constant. Thereby, the vibration of the coil 3 and the core 2 can be absorbed by the damping material 6, and noise and the like can be easily suppressed.
Further, when the reactor 15 is manufactured, if the member 15 is put into the storage case 5 with a strong force so that the end surface 41 of the core member 4 always comes into contact with the contact portion 51, the damping material 6 becomes thicker than necessary. Can be prevented. If the damping material 6 becomes too thick, problems such as a decrease in heat dissipation tend to occur.
In this example, since the damping material 6 is filled also in the side surface side gap 11, it is possible to prevent the vibration of the coil 3 and the like from being transmitted to the side surface of the case. Thereby, noise can be effectively suppressed.

In this example, as shown in FIGS. 2 and 3, the case bottom surface 50 is configured such that the contact portion 51 protrudes from the outer peripheral side.
In this case, since the contact portion 51 is formed to protrude, when the member 15 is put in the storage case 5, the end surface 41 of the core member 4 contacts the contact portion 51, and the bottom surface on the outer peripheral side thereof The side gap 10 is reliably formed. Moreover, if the protrusion height of the contact part 51 is determined in advance, the thickness of the damping material 6 will not be thinner than that height.

As shown in FIGS. 2 and 3, the reactor 1 of this example is filled with the damping material 6 between the outer surface 7 a of the protrusion 7 and the inner surface 40 a of the recess 40. More specifically, the damping material 6 enters the gap d2 between the backbone 70 and the core member 4 and further into the gap d3 above the gap d2.
With this configuration, for example, as shown in FIG. 7, the core 2 can be fixed to the storage case 5 by inserting the bolt 80 into the female screw portion 45 of the protrusion 7. Further, as shown in FIG. 2, the damping material 6 is filled between the outer surface 7 a of the protrusion 7 and the inner surface 40 a of the recess 40. Since the vibration damping material 6 (urethane resin or the like) has a higher thermal conductivity than air, the above structure is not filled with the vibration damping material 6 and heat is moderate compared to the case where an air layer is present. It becomes easy to be transmitted from the core member 4 to the storage case 5. Therefore, heat dissipation can be improved.

As shown in FIG. 2, the gap d <b> 1 between the reduced diameter portion 71 and the core member 4 is narrower than the gap d <b> 2 between the backbone 70 and the core member 4.
In this way, the member 15 (see FIG. 7) can be fixed at an accurate position with respect to the storage case 5. Thereby, the side surface side gap 11 mentioned above can be controlled accurately, and the thickness of the damping material 6 on the side surface can be easily controlled. If the damping material 6 becomes too thin, noise will be transmitted easily, and if it becomes too thick, the heat dissipation will decrease. However, by adopting the above configuration, the thickness of the damping material 6 can be controlled, and the noise suppression effect and heat dissipation will be reduced. And will be able to demonstrate both.

  On the other hand, the bottom side gap 10 is preferably 0.5 to 2.0 mm. Moreover, it is preferable that the side surface side gap 11 is 0.5-2.0 mm. If the bottom surface side gap 10 is less than 0.5 mm or the side surface side gap 11 is less than 0.5 mm, the vibration damping material 6 becomes too thin, and vibration may not be sufficiently absorbed. In addition, when the bottom surface side gap 10 exceeds 2.0 mm or the side surface side gap 11 exceeds 2.0 mm, the damping material 6 becomes too thick, and thus the heat of the core 2 is difficult to be transmitted to the storage case 5. There is.

As described above, according to this example, it is possible to provide the reactor 1 in which the thin film of the damping material 6 can be formed with a certain thickness between the case bottom surface 50 and the core bottom surface 20 and vibration and noise are hardly generated. it can.
(Reference Example 1)
Next, a reference example of the reactor 1 is shown in FIG. In the reactor 1, the end portion 42 of the core member 4 protrudes from the core bottom surface 20, and the end portion 42 is in contact with the case bottom surface 50.
If comprised in this way, it can prevent that the core bottom face 20 and the case bottom face 50 contact, and can prevent that the space | interval of the bottom face side gap | interval 10 becomes too narrow similarly to the structure of FIG.
In addition, since the end portion 42 of the core member 4 protrudes from the core bottom surface 20, the bottom surface side gap 10 can be reliably formed even if the case bottom surface 50 is flat. In addition, if the protruding height of the end portion 42 is determined in advance, the thickness of the damping material 6 will not be thinner than that height.
(Reference Example 2)
Further, as shown in FIG. 10, a bottom raising member 44 may be interposed between the core member 4 and the storage case 5. The bottom raising member 44 is preferably made of metal. Since heat conductivity is high if it is a metal, heat is conducted from the core member 4 to the storage case 5 quickly. Thereby, the heat generated from the core 2 and the like can be effectively transmitted to the storage case 5.

DESCRIPTION OF SYMBOLS 1 Reactor 10 Bottom face side gap 11 Side face side gap 2 Core 20 Core bottom face 3 Coil 4 Core member 5 Storage case 50 Case bottom face 6 Damping material

Claims (4)

A core made of a magnetic powder mixed resin in which a magnetic powder is dispersed in a resin;
A coil embedded in the core and generating magnetic flux when energized;
A core member that is positioned inside the coil and is formed in a columnar shape facing the axial direction of the coil, and is embedded in the core with at least one end face in the axial direction exposed from the bottom surface of the core When,
A storage case for storing the core together with the coil and the core member;
The case bottom surface of the storage case and the end surface of the core member are in direct or indirect contact with each other, and a bottom side gap is provided between the case bottom surface and the core bottom surface on the outer peripheral side of the contact portion. A side-side gap is provided between the inner peripheral surface of the storage case and the outer peripheral surface of the core, and the bottom-side gap and the side-side gap are located more than the core. It is filled with a damping material made of a material with a small Young's modulus ,
The reactor is characterized in that the bottom surface of the case is configured such that the contact portion protrudes toward the core member rather than the outer peripheral portion. Oite to claim 1, the ends of the central core member reactor, characterized in that projecting from the core base, the end portion in contact with the bottom of the case. 3. The storage case according to claim 1, wherein the storage case has a core fixing projection at the bottom of the storage case, and the core member has a recess that fits into the projection. A reactor in which the damping material is filled between the outer surface of the part and the inner surface of the recess. 4. The concave portion according to claim 3, wherein the protrusion includes a trunk portion protruding from a bottom portion of the storage case, and a reduced diameter portion provided on a distal end side of the trunk portion and having an outer diameter smaller than the trunk portion. Is formed in a stepped shape that fits into each of the backbone portion and the reduced diameter portion, and a gap between the reduced diameter portion and the core member is narrower than a gap between the backbone portion and the core member. Reactor characterized by becoming.

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