JP2008182075A - Reactor - Google Patents

Abstract

Vibration and noise of a reactor including an annular core configured by assembling a plurality of core blocks formed from a compacted body of magnetic powder are suppressed.
An annular core 2 is formed by assembling a plurality of core blocks 4, 5 a, 5 b, 5 c formed of magnetic powder compacts through spacers 6, and an outer periphery of the annular core. A reactor comprising a provided coil 3 and a case for housing them, and comprising a fastening means 8 for fastening one or more of the core blocks or fastening the core blocks and the case together. did.
[Selection] Figure 3

Description

  The present invention relates to a reactor mounted on an electric vehicle such as a hybrid vehicle or a fuel cell vehicle.

  In recent years, automobiles that run by driving a motor with a DC power source such as a hybrid vehicle and a fuel cell vehicle have been developed due to environmental problems. These automobiles are equipped with a boost converter that boosts the voltage of a battery that is a DC power source. The step-up converter includes a reactor and a switching circuit.

  The reactor includes an annular core and a coil attached to the core. In a vehicle-mounted reactor, a pair of parallel I-shaped parts are configured by assembling two or more rectangular parallelepiped core blocks due to restrictions on mounting space, manufacturing method, and the like, and substantially U at both ends of these I-shaped parts. In many cases, a substantially elliptical annular core configured by connecting letter-shaped core blocks is employed.

  In the step-up converter, the on / off operation of the switching circuit is frequently repeated. Therefore, the vibration of the core is induced in conjunction with the switching cycle.

  There are several possible causes of the vibration, but the main causes are the electromagnetic attractive force and the magnetostrictive effect acting between the core blocks. That is, when the reactor coil having the above configuration is energized, due to the shape of the core and the shape of each core block, an electromagnetic attraction force is generated on the joint surface of the core block to form the magnetic body. They attract each other, and when a magnetic field is applied, the magnetic material itself is deformed by the magnetostrictive effect.

  Noise is generated by the vibration of the core, and this vibration is transmitted to a bobbin, a case, and the like provided around the core, and secondary and tertiary noises are also generated. On the other hand, in order to ensure heat dissipation, it is also difficult to vibration-insulate the core in the case. For this reason, vibrations of the case and the like are also transmitted through the air, generating unpleasant noise. It is also clear that the energy conversion efficiency of the reactor itself decreases when the above vibration occurs.

  In a reactor having a core formed of a laminated steel plate, a technique for suppressing the vibration by caulking the laminated steel plate with rivets has been proposed.

JP 11-186062 A

In the reactor described in the patent document, noise is reduced by setting the caulking pressure of the rivet to 50 kg / cm ² . However, it is very difficult to manage the rivet caulking pressure with high accuracy. It is also difficult to apply a large caulking pressure.

  In the reactor described in the above-mentioned patent document, a core formed from laminated steel plates is adopted, but it is necessary to form rivet holes in each steel plate, which increases the manufacturing cost. Moreover, since it is necessary to provide a rivet in the lamination direction of a laminated steel plate, it is difficult to make the said crimping pressure act with respect to the direction which a vibration generate | occur | produces according to the form of a reactor, etc.

  This invention makes it a subject to relieve | moderate effectively the vibration and noise of a reactor provided with the cyclic | annular core comprised by assembling the several core block formed from the compacting body of magnetic powder.

  The invention described in claim 1 is an annular core configured by assembling a plurality of core blocks formed of a compacted body of magnetic powder via a spacer, and a coil provided on the outer periphery of the annular core And a reactor that accommodates these, and includes a fastening means for fastening one or more of the core blocks or fastening the core blocks and the case together.

  Magnetostriction also occurs in the core block alone. Therefore, the vibration due to the magnetostriction can be suppressed by tightening one core block. Further, by tightening two or more core blocks, vibration due to electromagnetic attractive force or magnetostriction generated between these core blocks can be suppressed. Further, by tightening the core block and the case, the vibration of the case can be suppressed integrally with the annular core. For this reason, generation | occurrence | production of noise etc. can be suppressed.

  As the tightening means, screw means can be adopted as in the invention described in claim 2. For example, bolts and nuts can be employed as the screw means. Various forms can be adopted as the fastening form. For example, a single core block can be tightened by providing a through hole in a specific core block where vibration is likely to occur, and a bolt inserted through the through hole and a nut screwed into the bolt. Further, the plurality of core blocks can be tightened together by providing a through hole in two or more core blocks, and a bolt inserted into the through hole and a nut screwed into the through hole. In this invention, since the core formed from a compacting body is employ | adopted, the said bolt insertion hole etc. can be formed easily. Therefore, the core manufacturing cost does not increase.

  Further, a female screw communicating with the through hole is formed in one core block or case, and a bolt and the female screw are screwed together to constitute a fastening means for fastening two or more core blocks or core blocks and the case together. You can also.

  Further, it is possible to constitute a fastening means for fastening the core from the outside of the annular core to suppress vibration. For example, a tightening means that suppresses vibration can be configured by using a frame-shaped or group-shaped member that can be clamped by sandwiching the outer peripheral portion of the annular core from both sides.

  The fastening means such as bolts and nuts are preferably made of a nonmagnetic material such as stainless steel that does not affect the magnetic circuit. Moreover, the fastening force by the said fastening means can be set according to forms, such as an annular core and a case. For example, it is preferable to apply a tightening force of about 50 MPa.

  According to a third aspect of the present invention, a pinching member is provided between the tightening means and the core block.

  Screw means such as bolts and nuts constituting the tightening means apply a tightening force in the axial direction of the bolt via a seating surface where the bolt head and the nut come into contact. For this reason, when the said axis line remove | deviates from the part which generate | occur | produces a vibration, the case where a vibration cannot be suppressed effectively is also considered. Moreover, when the core block with which the bolt head and the nut are brought into contact with each other is deformed, there may be a case where the tightening force cannot be applied to other core blocks evenly. In such a case, by providing the clamping member, it is possible to apply a uniform tightening force over a wide range, or to displace the operating point of the tightening force and apply the tightening force to a desired part. Become.

  The clamping member can be configured to be clamped by the clamping means and to exert an elastic pressing force on a portion other than the seating surface of the clamping means. For example, the pressing member can be configured to be elastically deformed by the tightening means and to apply an elastic pressing force to a portion away from the seating surface of the screw means or the like. By applying an elastic pressing force to a predetermined portion of the annular core via the pinching member, vibration can be more effectively suppressed. The clamping member is also preferably formed from a nonmagnetic material that does not affect the magnetic circuit. Of course, like the general washer, the pinching member has an effect of preventing the fastening means from loosening and preventing the seat surface from being damaged.

  Further, as the clamping member, a member formed of a material that can be elastically deformed or elasto-plastically deformed between the bolt head or nut and the seat surface can be employed. By holding the pressing member against the core block surface in a deformed state, the unevenness of the seating surface is absorbed to increase the contact area, and a high vibration damping effect can be expected. For example, a vibration-damping rubber material or a metal plate that is partially plastically deformed in a state in which a pressing force is applied can be employed. When an elasto-plastic material that is partly plastically deformed at a predetermined damping pressure is used, the tightening force can be easily managed.

  According to a fourth aspect of the present invention, there is provided a pair of parallel I-shaped parts in which two or more core blocks are assembled, and a pair of substantially U-shaped cores connected to both ends of these I-shaped parts. It is configured with blocks.

  The core of the above form is often employed in a vehicle-mounted reactor, and when vibration occurs, the driver feels unpleasant noise. In this type of core, an electromagnetic attractive force acts in the axial direction of the I-shaped portion, and therefore a large vibration suppressing effect can be obtained by applying a tightening force in this direction.

  The invention described in claim 5 of the present application is provided with a fastening means for fastening the plurality of core blocks constituting the I-shaped portion to each other.

  For example, as the tightening means, a bolt insertion hole penetrating each core block constituting the I-shaped portion is provided, and a bolt is continuously inserted into the bolt insertion hole, and a nut is screwed into the tightening means. Can be configured.

  Moreover, the core block which comprises the said I-shaped part can be integrally assembled | attached by the said fastening means by employ | adopting the said structure. For this reason, it is possible to omit the adhesive provided between the core block and the spacer, and it is possible to increase the efficiency of the assembly work of the core.

  According to a sixth aspect of the present invention, there is provided a fastening means provided between the pair of substantially U-shaped core blocks so as to span the I-shaped portion and the substantially U-shaped core block. is there.

  For example, the pair of substantially U-shaped core blocks are provided with bolt insertion holes that communicate with the inner side of the annular core, and are screwed into the bolts that are inserted into the bolt insertion holes through the inner part of the annular core. The tightening means can be constituted by a nut.

  The tightening means applies a tightening force to the I-shaped portion so as to be sandwiched between substantially U-shaped cores arranged on both sides. For this reason, the whole annular core can be efficiently tightened with a set of bolts and nuts. Moreover, since the said annular core can be assembled | attached with one set of volt | bolt nuts etc., the efficiency of an assembly | attachment operation | work can be improved like Claim 4.

  According to a seventh aspect of the present invention, there is provided a fastening means provided between the annular core block and the case so as to span the I-shaped portion, the substantially U-shaped core block, and the case. It is provided.

  By employ | adopting the said structure, the said annular core and the case which accommodates this can be clamp | tightened integrally. For this reason, it is possible to integrally suppress vibrations of the annular core and the case. Moreover, since the structure which hold | maintains the said cyclic | annular core to the said case is combined, it also becomes possible to improve the assembly | attachment workability | operativity of a reactor more.

  According to an eighth aspect of the present invention, there is provided a fastening means that is provided in a spanning manner in a direction orthogonal to the annular surface of the annular core and that fastens the substantially U-shaped core block and the case. .

  In a reactor provided with the annular core of the said form, a coil is provided in the outer periphery of the said I-shaped part. For this reason, a fastening means can be comprised, without changing the form of a reactor or a case by fastening the said substantially U-shaped part in the direction orthogonal to the said annular surface.

  By tightening one or two or more core blocks, or by tightening these core blocks and the case together, it is possible to suppress reactor vibration and noise due to magnetic attractive force or magnetostriction.

  1 to 3 show a first embodiment of the present invention.

  As shown in FIG. 1 and FIG. 2, the reactor 1 includes an annular core 2 and a coil 3 attached around the core 2. Usually, a bobbin (not shown) for holding the coil 3 at a predetermined interval around the outer periphery of the core 2 is inserted between the core 2 and the coil 3 and the whole is formed into a box-shaped case. Contained.

  FIG. 3 shows a cross section taken along line III-III in FIG.

  In the present embodiment, a pair of parallel I-shaped parts 5 is formed by assembling three rectangular parallelepiped core blocks 5 a, 5 b, 5 c, and substantially U-shaped core blocks 4 are formed at both ends of these I-shaped parts 5. , 4 are connected to form a substantially oval annular core 2. Spacers 6 formed of a ceramic material which is a non-magnetic material are inserted in gaps set between the core blocks.

  In the reactor including the annular core 2 having the above configuration, a magnetic attractive force acts on the joint surface of each core block with the spacer 6 interposed therebetween, and the I-shaped portion 5 is likely to vibrate in the axial direction.

  In the present embodiment, the bolt 8a provided in a spanning manner through the center portion of the annular core to the pair of substantially U-shaped core blocks 4 and 4 and a nut 8b screwed to the bolt 8a, A fastening means 8 for fastening the annular core 2 in the axial direction of the I-shaped portion is configured. The bolt 8a and the nut 8b are made of a nonmagnetic material such as stainless steel.

  The substantially U-shaped core blocks 4, 4 are formed with bolt insertion holes 7, 7 leading to the inner side of the annular core 2. In addition, the cylindrical outer peripheral portions of the substantially U-shaped core blocks 4 and 4 are cut out with a predetermined width in a direction orthogonal to the generatrix, thereby forming the seat surfaces 10 and 10 of the bolt 8a and the nut 8b. The nuts 8b are screwed into bolts 8a that are inserted into the bolt insertion holes 7 and 7 through the inner portion of the annular core 2 to thereby form the pair of I-shaped portions 5 and the substantially U-shaped core block 4. Is tightened in the axial direction of the I-shaped portion 5 by the tightening means 8 including the bolt 8a and the nut 8b.

  The seating surfaces 10 and 10 are set to a depth that can accommodate the head of the bolt 8a and the nut 8b, and the fastening means 8 can be secured without greatly changing the form of the annular core 2 or a case for housing the same. Can be configured.

  The U-shaped core blocks 4 and 4 and the I-shaped portions 5 and 5 are integrally tightened by the tightening means 8. Thereby, the vibration of the axial direction which arises in the said I-shaped part 5 can be suppressed. It is desirable that the tightening means 8 adjust the tightening force of the tightening means 8 so that a pressure of about 50 MPa acts on the I-shaped portion.

  Further, as is apparent from FIG. 3, the core blocks constituting the annular core 2 can be integrally assembled by the fastening means 8 comprising the bolts 8a and the nuts 8b. For this reason, it is possible to reduce or omit the amount of adhesive provided between each core block and the spacer, and to simplify the assembling work.

  FIG. 4 shows a second embodiment.

  In the second embodiment, there is provided fastening means 28 for fastening a pair of I-shaped portions 25 configured by assembling rectangular parallelepiped core blocks 25a, 25b, 25c directly in the axial direction using bolts 28a and nuts 28b. ing.

  Bolt insertion holes 27a, 27b, 27c, 26a, 26a penetrating in the axial direction are formed in the rectangular core blocks 25a, 25b, 25c and the spacers 26 inserted therebetween. In addition, a concave portion 29a capable of accommodating the head of the bolt 28a and the nut 28b is formed at a joint portion between the substantially U-shaped core blocks 24, 24 and the rectangular core blocks 25a, 25c at both ends of the I-shaped portion 25. 29b, and a hole 26b corresponding to the recess is formed in the central portion of the spacer 26. The I-shaped portion 5 is tightened in the axial direction by the bolt 28a inserted into the bolt insertion holes 27a, 27b, and 27c and the nut 28b screwed into the bolt 28a.

  By adopting the above configuration, it is possible to suppress vibration caused by magnetic attraction force or the like in the pair of I-shaped portions 5. Moreover, since the said fastening means 28 is accommodated in the inside of the annular core 22, the form of the annular core 22 is not changed greatly.

  FIG. 5 shows a third embodiment of the present invention.

  In this embodiment, a pinching member 39 is provided between the head of the bolt 38 a and the nut 38 b and the seat surface 30 a of the substantially U-shaped core block 34.

  The clamping member 39 includes a flat portion 39a along the seating surface 30a, and curved portions 39b and 39b that extend from both sides of the flat portion 39a and bend along the outer surface of the substantially U-shaped core block 34. It is configured with. On the outer surface of the substantially U-shaped core block 34, concave portions 30b, 30b for accommodating the curved portions 39b, 39b are formed.

  The curved portions 39b and 39b of the pinching member 39 are formed with a radius of curvature smaller than the radius of curvature of the concave portions 30b and 30b in a natural state where no tightening force is applied, as indicated by broken lines.

  When the clamping member 39 is clamped between the nut 38b and the seat surface 30a, the curved portions 39b and 39b are brought into contact with the concave portions 30b and 30b of the substantially U-shaped core block, and It is elastically deformed in the direction of arrow W. As a result, an elastic force in the direction indicated by the arrow F acts on the substantially U-shaped core block 34. The elastic force F can suppress vibration in the direction in which both ends of the substantially U-shaped core block 34 open and close. Further, the tightening force of the substantially U-shaped core block can be evenly applied to the pair of I-shaped portions.

  6 and 7 show a fourth embodiment of the present invention. The form of the annular core is the same as that of the first embodiment, and the description thereof is omitted.

  In this embodiment, a fastening means 48 for fastening the annular core 42 together with a case 50 for housing the annular core 42 is provided.

  As shown in FIG. 6, the case 50 is formed with an accommodation space 50 a corresponding to the shape of the annular core 42. Further, a step portion 50b for holding the substantially U-shaped portion is formed at the bottom of the case 50, and the I-shaped portion 45 of the annular core and the coil 43 wound around this are floated in the case 50. It is configured so that it can be held in a state.

  In this embodiment, the substantially U-shaped core blocks 44 a and 44 b are formed with bolt insertion holes 47 b and 47 c that communicate with the inside of the annular core 42, and the bolts are inserted into one side wall 50 c of the case 50. Bolt insertion holes 47a communicating with the holes 47b and 47c are formed. A tightening means 48 for tightening the case 50 and the annular core 42 integrally using a bolt 48a inserted into the bolt insertion holes 47a, 47b, 47c and a nut 48b screwed to the bolt 48a. Provided.

  By integrally tightening the case 50 and the annular core 42, vibration generated in the annular core 42 can be efficiently suppressed.

  Further, the annular core 48 and the case 50 can be reliably brought into contact with each other by the fastening means 48. For this reason, the heat dissipation of the annular core 48 is also improved.

  FIG. 8 shows a fifth embodiment of the present invention.

  In this embodiment, a fastening means 58 for fastening the pair of substantially U-shaped core blocks 54, 54 to the bottom surface of the case 60 is provided.

  Bolt insertion holes 57a and 57a are formed in the pair of substantially U-shaped core blocks 54 and 54 in a direction orthogonal to the annular surface. On the other hand, the stepped portion 60b of the case 60 is formed with a screw hole 58b into which the bolt 58a is screwed.

  The substantially U-shaped core block, 54, 54, and the case 60 can be integrally tightened by screwing the bolt 58a inserted through the bolt insertion holes 57a, 57a into the screw hole 58b. .

  In the embodiment, the I-shaped portion is formed by three core blocks. However, the number and form of the core blocks are not limited to the embodiment.

  The present invention is not limited to the above-described embodiments. The embodiments disclosed herein are illustrative in all respects and should not be construed as being restrictive. The scope of the present invention is defined not by the above-described meaning but by the scope of the claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

  According to the present invention, the vibration of the annular core can be suppressed, so that a low noise reactor can be provided.

It is a perspective view which shows the external appearance of 1st Example of the reactor which concerns on this invention. It is a side view of the reactor shown in FIG. It is sectional drawing which follows the III-III line | wire in FIG. It is a figure which shows the 2nd Example of the reactor which concerns on this invention, and is sectional drawing equivalent to FIG. It is a figure which shows the 3rd Example of the reactor which concerns on this invention, and is sectional drawing of the principal part corresponded in FIG. It is a top view which shows the 4th Example of the reactor which concerns on this invention. It is sectional drawing which follows the VII-VII line in FIG. It is a figure which shows the 5th Example of the reactor which concerns on this invention, and is sectional drawing equivalent to FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reactor 2 Ring core 3 Coil 4 Core block 5a Core block 5b Core block 5c Core block 6 Spacer 8 Tightening means

Claims (8)

An annular core configured by assembling a plurality of core blocks formed of a compacted body of magnetic powder via a spacer, a coil provided on the outer periphery of the annular core, and a case for housing these A reactor with which
A reactor comprising a fastening means for fastening one or more of the core blocks, or fastening the core blocks and the case together.   The reactor according to claim 1, wherein the fastening means is a screw means.   The reactor in any one of Claim 1 or Claim 2 provided with the pinching member inserted between the said clamping means and the said core block.   The annular core includes a pair of parallel I-shaped parts assembled with two or more core blocks, and a pair of substantially U-shaped core blocks connected to both ends of the I-shaped parts. The reactor in any one of Claims 1-3.   The reactor of Claim 4 which provided the fastening means which fastens the several core block which comprises the said I-shaped part mutually.   5. The reactor according to claim 4, further comprising a fastening means that is provided between the pair of substantially U-shaped core blocks so as to tighten the I-shaped portion and the substantially U-shaped core block.   5. The reactor according to claim 4, wherein the reactor is provided in a spanning manner between the annular core and the case, and is provided with fastening means for fastening the I-shaped portion, the substantially U-shaped core block, and the case to each other. .   The reactor according to claim 4, further comprising a fastening unit that is provided in a direction orthogonal to the annular surface of the annular core and fastens the substantially U-shaped core block and the case together.

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