JP2008041879A - Reactor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the material cost and manufacturing cost of a reactor, and further to improve the performance of the rector by reducing an influence of leakage magnetic flux. <P>SOLUTION: The reactor 1 is provided with a circular core 2 formed of a magnetic body, and a coil 3 provided at the external circumference of a predetermined part of this core. In the reactor 1, a bobbin 4 is provided at the external circumference of the core, and the coil is formed by winding a plurality of winding wires 5a, 5b having round cross sections in parallel with the external circumference of the bobbin. <P>COPYRIGHT: (C)2008,JPO&INPIT

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 supply, and a reactor is a main component of the boost converter.

  As described in Patent Document 1, the reactor includes an annular core and a coil wound around a predetermined portion of the core. In a vehicle-mounted reactor, a pair of parallel I-shaped parts are formed by assembling two or more core blocks, respectively, due to restrictions on mounting space, manufacturing method, etc., and substantially U-shaped cores at both ends of these I-shaped parts. In many cases, a substantially oval annular core configured by connecting blocks is employed. By passing a current through the coil, an annular magnetic circuit is formed in the core.

JP 2003-77746 A

  In the reactor described in Patent Document 1, a coil shaped body is formed by winding a conducting wire having a rectangular cross section in advance into a rectangular cylindrical shape, and a rectangular core is formed in the cylindrical inner space of the coil molded body. Is inserted and fixed, a coil is provided on the outer periphery of the I-shaped portion. Thereafter, a manufacturing method is adopted in which a substantially U-shaped core block is connected to both ends of the I-shaped portion to form an annular body.

  When the coil molded body is employed, a thick winding having a rectangular cross section must be accurately formed into a rectangular cylindrical shape, which requires a special manufacturing apparatus and increases the material cost and processing cost. .

  In addition, since the rectangular core block must be inserted and fixed in the cylindrical inner space of the coil molded body, a certain amount of gap is provided between the inner periphery of the coil molded body and the rectangular core block. Must be secured. If the gap between the coil and the core becomes large, not only will the performance of the coil be reduced, but if there is a backlash or the like, it will cause vibration and noise. For this reason, in the reactor described in Patent Document 1, a special positioning jig that fixes the winding of the coil to the outer periphery of the core is employed, but this increases the cost.

  In addition, when the coil molded body is used, a rectangular winding having a large cross-sectional area is used, so that the influence of leakage magnetic flux extends over a large range of the coil cross-section, and eddy current is likely to occur. There is a problem that becomes larger.

  The present invention provides a reactor that not only solves the above-described conventional problems and can reduce the material cost and the manufacturing cost, but also can improve the performance by reducing the influence of leakage magnetic flux.

  The invention described in claim 1 is a reactor including an annular core formed of a magnetic material and a coil provided on an outer periphery of a predetermined portion of the core, wherein a bobbin is provided on the outer periphery of the core, and the coil Is formed by winding a plurality of windings having a circular cross section around the bobbin in parallel.

  In the present invention, a coil is formed by winding a winding directly on the outer periphery of a core provided with a bobbin. Since the coil can be formed by directly winding the winding around the outer periphery of the core, a special coil molding machine or the like is not necessary, and the processing cost of the coil can be reduced.

  In order to directly wind the winding wire constituting the coil around the core, a certain degree of flexibility is required for the winding wire, and thus a winding wire having a large cross-sectional area equivalent to that of the conventional winding wire cannot be employed. Further, the number of turns of the windings determines the reactor characteristics (inductance) and cannot be changed.

  In the present invention, a plurality of windings having a circular cross section are wound in parallel in order to ensure a cross-sectional area of the winding and a specified number of turns. That is, a winding assembly consisting of a plurality of windings thinner than the conventional winding is wound around the core outer periphery as a single winding.

  By winding a plurality of windings in parallel, the cross-sectional area per wire can be reduced. For this reason, the deformation resistance of the winding becomes small and can be easily wound around the outer periphery of the core. On the other hand, by setting the cross-sectional area of the plurality of winding assemblies to be the same as the cross-sectional area of the conventional winding, a specified current value and number of turns can be secured. Moreover, the winding with a circular cross section is less expensive than the winding with a rectangular cross section employed in the coil molded body, and the material cost can be reduced.

  Furthermore, in the present invention, since the winding can be directly wound around the outer periphery of the core, it is not necessary to set a large gap between the outer periphery of the core and the inner peripheral portion of the winding. Usually, a bobbin formed of an insulating material is interposed between the core and the winding, but the winding can be wound in a state where the bobbin is in close contact with the outer periphery of the core. For this reason, it becomes possible to make a coil inner peripheral part adjoin to a core outer peripheral part, and a coil can be reduced in size by that.

  According to a second aspect of the present invention, a guide groove for winding the winding is provided on the outer periphery of the bobbin.

  The guide groove is formed according to the cross section of the winding and the number of windings wound in parallel. For example, when two windings are wound in parallel, two spiral guide grooves are formed.

  By providing the guide groove, the winding can be wound while guiding the winding, so that the winding operation is facilitated. In addition, by providing the guide groove, it is possible to increase the density of the winding on the outer periphery of the core by regularly winding the winding, and to reduce the size of the device by reducing the cross-sectional area of the coil forming portion on the outer periphery of the core. Can also be planned.

  In the invention described in claim 3 of the present application, the annular core is composed of a pair of parallel I-shaped portions around which the coil is wound, and a substantially U-shaped portion connected to both ends of these I-shaped portions. In addition, the coil is formed by winding the winding around the outer periphery of a bobbin provided in the pair of parallel I-shaped portions.

  The invention described in claim 3 is the one in which the present invention is applied to a reactor of a form that is often employed in a hybrid vehicle or the like. Thereby, in this kind of reactor, while being able to reduce material cost and processing cost, it becomes possible to reduce loss.

  Further, as in the invention described in claim 4, the pair of parallel I-shaped portions can be configured by integrally joining a plurality of rectangular core blocks with spacers interposed therebetween.

  The invention described in claim 5 of the present application is a method for manufacturing a reactor including an annular core formed of a magnetic material and a coil provided on an outer periphery of a predetermined portion of the core, and a part of the annular core. A coil forming step of winding a plurality of windings having a circular cross section in parallel on the outer periphery of the bobbin attached to

  The invention described in claim 6 of the present application is an application of the invention described in claim 5 to a method of manufacturing a reactor in a form that is often employed in a hybrid vehicle or the like. That is, a method of manufacturing a reactor in which the annular core includes a pair of parallel I-shaped portions provided with the coils and substantially U-shaped portions connected to both ends of the I-shaped portions. The I-shaped part forming step of forming the I-shaped part by connecting the rectangular core blocks with a spacer interposed therebetween, and the bobbin attaching process of attaching a bobbin provided with a guide groove on the outer periphery of the I-shaped part A coil forming step for winding the winding along the guide groove, and a substantially U-shaped portion for connecting a substantially U-shaped core block to both ends of the I-shaped portion wound with the winding. And a connecting step.

  According to the present invention, not only the material cost and manufacturing cost of the reactor can be reduced, but also the performance of the reactor can be improved by reducing the influence of leakage magnetic flux.

  As shown in FIG. 1, the reactor 1 includes an annular core 2 and a coil 3 mounted around the core 2. As shown in FIG. 3, between the core 2 and the coil 3, a bobbin 4 for holding the coil 3 on the outer peripheral portion of the core 2 with a predetermined interval is inserted and the whole is shown. It is housed in a box-shaped case.

  FIG. 2 is an overall perspective view of the annular core. In the present embodiment, a pair of parallel I-shaped portions 6 and 6 are formed by assembling three rectangular core blocks 6a, 6b and 6c, respectively, and substantially U-shaped at both ends of these I-shaped portions. A substantially oval annular core 2 is formed by connecting the core blocks 7 and 7. Spacers 8 made of a ceramic material that is a non-magnetic material are interposed between the core blocks 7, 6a, 6b, and 6c. A rounded portion 9 is formed at the outer peripheral corner of the rectangular core block so that the winding can be wound directly. These core blocks 7, 6a, 6b, 6c are integrally joined using an adhesive.

  In the present embodiment, the substantially U-shaped core block 7 has a core cross-sectional area in the direction from the axial center of the substantially U-shaped core block to the outer periphery and the axial direction with respect to the cross section of the I-shaped portion 6. It is formed in a form in which the core cross-sectional area in the direction along (the vertical direction on the paper) is increased. Step portions 10 and 11 are formed at the connecting portion between the I-shaped portion 6 and the substantially U-shaped core block 4 by increasing the core cross-sectional area.

  FIG. 3 is a perspective view showing a state where the bobbin 4 is mounted on the I-shaped portion 6. The bobbin 4 is formed by using an insulating resin material and including a cylindrical portion 4a attached to the outer periphery of the I-shaped portion 6 and a flange portion 4b attached to the stepped portion. ing. The bobbin 4 is desirably formed in a thin shape so that the inner peripheral surface of the coil and the outer peripheral surface of the core can be held with a distance as small as possible.

  As shown in FIG. 4, a guide groove 12 corresponding to the thickness of the winding 5 constituting the coil is formed on the outer periphery of the tubular portion 4 a of the bobbin 4. In the present embodiment, the guide is formed by forming two semicircular grooves in parallel on the outer peripheral surface of the bobbin 4 so that two windings having a circular cross section can be wound in parallel. A groove 12 is formed. By providing the guide groove 12, the winding work can be facilitated and the winding 5 can be wound with high density. In the embodiment, the winding is wound in three layers in the annular space formed by the flange portion and the cylindrical portion.

  The reactor is manufactured as follows.

  First, the rectangular core blocks 6a, 6b, 6c are integrated by interposing the spacers 8 therebetween to form a rectangular bar-shaped I-shaped portion 6. Next, the bobbin 4 is attached to the outer periphery of the I-shaped part 6 by inserting the I-shaped part 6 into the cylindrical part 4 a of the bobbin 4. And the coil | winding 5 is wound around the outer periphery of the cylindrical part 4a of the said bobbin 4, and the coil 3 is formed. Since the flange 4b and the guide groove 12 are formed on the bobbin 4, the winding 5 can be easily wound.

  As shown in FIG. 5, in this embodiment, the coil 3 is formed by winding two windings having a circular cross section in parallel. By winding a plurality of windings in parallel, a coil having the same cross-sectional area and number of turns as a conventional coil having a rectangular cross section can be formed.

  Further, the winding having a circular cross section is inexpensive, and the material cost of the coil 3 can be reduced. In addition, since the necessary cross-sectional area of the coil is divided into a plurality of windings and wound, the deformation resistance is small, and the winding can be wound directly on the bobbin 4. Therefore, the processing cost can be greatly reduced as compared with the conventional coil molded body.

  Further, since the winding 5 can be directly wound around the bobbin 4 attached to the I-shaped portion 6, the inner peripheral portion of the coil 3 can be positioned close to the outer peripheral portion of the I-shaped portion 6. it can. As a result, loss can be reduced and coil efficiency can be improved. Further, since an extra gap is not required as in the case where a conventional coil molded body is mounted, the size of the coil winding portion can be reduced to reduce the size of the apparatus.

  Furthermore, conventionally, since a coil is formed by winding a single winding having a large cross-sectional area, the influence of leakage magnetic flux affects the entire coil cross section, resulting in a large loss. On the other hand, in this embodiment, since the conventional cross-sectional area is divided into a plurality of windings 5a and 5b and wound, the influence of leakage magnetic flux does not reach the internal windings. For this reason, the influence of the leakage magnetic flux given to the coil is reduced, and the loss can be reduced.

  In the above-described embodiment, the present invention is applied to the reactor 1 including a pair of I-shaped portions formed of three rectangular core blocks and an annular core formed of a substantially U-shaped core block. The present invention can be applied to a reactor having an annular core of the form.

  Further, although two windings are wound in parallel, three or more windings can be wound in parallel.

  In addition, the bobbin is formed in a cylindrical shape and attached by inserting an I-shaped part. However, the bobbin can be divided into two along the generatrix and assembled from the side of the I-shaped part. May be.

  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-mentioned 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.

It is a perspective view which shows the external appearance of the reactor which concerns on the Example of this invention. It is a perspective view which shows the external appearance of the core of the reactor shown in FIG. It is a perspective view which shows the state which mounted | wore the core shown in FIG. It is sectional drawing which follows the IV-IV line in FIG. It is explanatory drawing which shows the state which is winding the several coil | winding in parallel.

Explanation of symbols

1 Reactor 2 Ring Core 3 Coil 4 Bobbin 5a Winding 5b Winding

Claims (6)

A reactor comprising an annular core formed of a magnetic body and a coil provided on the outer periphery of a predetermined portion of the core,
While providing a bobbin on the outer periphery of the core,
The coil is a reactor formed by winding a plurality of windings having a circular cross section around the bobbin in parallel.   The reactor of Claim 1 which provided the guide groove which winds the said coil | winding in the outer periphery of the said bobbin. The annular core is composed of a pair of parallel I-shaped portions around which the coil is wound, and substantially U-shaped portions connected to both ends of these I-shaped portions,
The reactor according to claim 1, wherein the coil is formed by winding the winding around an outer periphery of a bobbin provided on the pair of parallel I-shaped portions.   The reactor according to claim 3, wherein the pair of parallel I-shaped portions are formed by integrally joining a plurality of rectangular core blocks with a spacer interposed therebetween. A reactor manufacturing method comprising an annular core formed of a magnetic body and a coil provided on an outer periphery of a predetermined portion of the core,
A method for manufacturing a reactor, comprising: a coil forming step of winding a plurality of windings having a circular cross section in parallel on an outer periphery of a bobbin attached to a part of the annular core. A method of manufacturing a reactor, wherein the annular core includes a pair of parallel I-shaped portions provided with the coil, and substantially U-shaped portions connected to both ends of the I-shaped portions,
An I-shaped portion forming step of forming the I-shaped portion by connecting a plurality of rectangular core blocks with a spacer interposed therebetween;
A bobbin attaching step of attaching a bobbin provided with a guide groove on the outer periphery of the I-shaped part;
A coil forming step of winding the winding along the guide groove;
The manufacturing method of the reactor of Claim 5 including the substantially U-shaped part connection process which connects a substantially U-shaped core block to the both ends of the said I-shaped part which wound the said coil | winding.

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