Noise filter unit and power conversion device

Abstract

To provide a noise filter unit in which a core cover accommodating a core is fixed to a housing such that the core cover is prevented from coming off from the housing.SOLUTION: There is provided a noise filter unit in which a conductor plate for connecting a battery and a power conversion circuit is inserted. The noise filter unit includes a core formed of a cylindrical magnetic body, a cylindrical core cover 13 accommodating the core, a housing 10 into which the core cover 13 can be inserted from a direction along the axis core of the core cover 13 so as to hold the inserted core cover 13, and a bonding layer for bonding the core cover 13 and the housing 10. A snap-fit structure 20 is provided for restricting movement of the core cover 13 relative to the housing 10 toward an opposite side to the insertion direction in which the core cover 13 is inserted into the housing 10.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a noise filter unit and a power conversion device. [Background technology]

[0002] For example, Patent Document 1 discloses a power conversion device that reduces the inductance of a noise filter circuit to increase output. The power conversion device disclosed in Patent Document 1 includes a power supply side conductor connected to a high-voltage battery and a core member through which the power supply side conductor passes. Such a core member suppresses electromagnetic noise by absorbing fluctuations in the current flowing through the power supply side conductor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6838775 Summary of the Invention [Problem to be solved by the invention]

[0004] The core member of the power conversion device disclosed in Patent Document 1 is formed in a cylindrical shape. Such a cylindrical core is housed in, for example, a core cover similarly formed in a cylindrical shape, and fixed to the housing. In addition, the conductor through which electric power is passed is formed in a plate shape and disposed so as to pass through the central opening of the core cover. Incidentally, the core cover housing the core is adhered to the housing using, for example, an adhesive. However, in a power conversion device mounted on a vehicle, the core cover may be detached from the housing due to vibrations during vehicle running, etc. The core cover can be supported by the conductor even if it is detached from the housing, since the conductor penetrates through the core cover. However, this may cause performance changes due to changes in the distance between the core and the conductor, or abnormal noise due to contact with surrounding members.

[0005] The present invention has been made in consideration of the above-mentioned problems, and has an object to prevent a core cover that houses a core from becoming detached from a housing in a noise filter unit in which the core cover is fixed to the housing. [Means for solving the problem]

[0006] The present invention employs the following configuration as a means for solving the above problems.

[0007] A first aspect of the present invention is a noise filter unit through which a DC transmission conductor connecting a battery and a power conversion circuit is inserted, the noise filter unit comprising a core made of a cylindrical magnetic material, a cylindrical core cover accommodating the core, a housing formed so that the core cover can be inserted from a direction along the axis of the core cover and holding the inserted core cover, and an adhesive layer bonding the core cover and the housing, and adopts a configuration in which a movement restriction structure is provided for restricting movement of the core cover relative to the housing in the direction opposite to the insertion direction when the core cover is inserted into the housing.

[0008] A second aspect of the present invention is a power conversion device comprising a power terminal connected to a battery and converting power passing through the power terminal, the power terminal comprising a noise filter unit according to the first aspect of the present invention for suppressing electromagnetic noise. Effect of the Invention

[0009] In addition to the adhesive layer that bonds the core cover and the housing, the present invention includes a movement restriction structure that restricts the movement of the core cover relative to the housing in the direction opposite to the insertion direction when the core cover is inserted into the housing. Therefore, even if the adhesion between the core cover and the housing is peeled off, the core cover can be prevented from coming off the housing. In addition, the movement restriction structure can bear a part of the load due to vibrations during driving of the vehicle, etc., and the load on the adhesive layer can be reduced. Therefore, the adhesive force of the adhesive layer can be prevented from decreasing. Therefore, the present invention makes it possible to prevent the core cover from coming off the housing in a noise filter unit in which a core cover that accommodates a core is fixed to the housing. [Brief description of the drawings]

[0010] [Figure 1] 1 is a circuit diagram showing a schematic electrical configuration of a power conversion device according to an embodiment of the present invention; [Diagram 2] 1 is an exploded perspective view showing a schematic structural outline of a power conversion device according to an embodiment of the present invention; [Diagram 3] 2 is a schematic exploded perspective view of a noise filter unit included in the power conversion device according to the embodiment of the present invention; FIG. [Figure 4] 2 is a schematic exploded perspective view of a core unit included in the power conversion device according to the embodiment of the present invention; FIG. [Diagram 5] 3 is a schematic cross-sectional view including a flexible piece and a protrusion of a noise filter unit included in a power conversion device according to an embodiment of the present invention. FIG. [Figure 6] 3 is a schematic enlarged perspective view including a flexible piece and a protrusion of a noise filter unit included in a power conversion device according to an embodiment of the present invention; FIG. [Figure 7] 13 is a schematic diagram of a housing included in a modified example of a noise filter unit included in a power conversion device according to an embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a noise filter unit according to an embodiment of the present invention will be described with reference to the drawings.

[0012] 1 is a circuit diagram showing a schematic electrical configuration of a power conversion device 1 of this embodiment. The power conversion device 1 of this embodiment is mounted on a vehicle such as an electric car, and is provided between a motor M and a battery B. The power conversion device 1 of this embodiment performs power conversion between the motor M and the battery B. For example, the power conversion device 1 of this embodiment converts DC power supplied from the battery B into three-phase AC power and supplies it to the motor M. The power conversion device 1 also converts regenerative power (AC power) from the motor M into DC power and supplies it to the battery B.

[0013] The power conversion device 1 of this embodiment has a power conversion circuit H as shown in Fig. 1. The power conversion circuit H converts DC power into AC power as described above. The power conversion circuit H also converts AC power into DC power. Such a power conversion circuit H includes a capacitor C, an inverter circuit E, and a noise filter F. The power conversion device 1 may also include, for example, a step-up / step-down converter or a DC-DC converter (not shown).

[0014] Moreover, the power conversion device 1 of this embodiment includes conductive lines BU through which power is conducted. For example, the power conversion device 1 of this embodiment includes a conductive line BU that connects the inverter circuit E and the battery B, and a conductive line BU that connects the inverter circuit E and the motor M.

[0015] As shown in FIG. 1, the inverter circuit E includes three legs R corresponding to the respective phases of the motor M. Each leg R includes an upper arm HA and a lower arm LA. The upper arm HA is connected to the positive electrode side of a battery B via a conductive line BU. The lower arm LA is connected to the negative electrode side of the battery B via a conductive line BU. The upper arm HA and the lower arm LA are connected in series. An output terminal that connects the legs R and the motor M is connected between the upper arm HA and the lower arm LA.

[0016] As shown in Fig. 1, the power conversion device 1 of this embodiment includes power devices D (semiconductor substrates) corresponding to each leg R. That is, in this embodiment, the power conversion device 1 includes three power devices D. Each power device D includes a power transistor corresponding to the upper arm HA and a power transistor corresponding to the lower arm. That is, in this embodiment, each power device D includes two power transistors. Each of these power transistors is formed using a plurality of semiconductor elements.

[0017] 1, the power conversion device 1 of this embodiment is provided with a noise filter F so as to surround a conductive line BU connected to the positive electrode side of the battery B and a conductive line BU connected to the negative electrode side of the battery B. This noise filter F suppresses changes in the current flowing through the conductive line BU, and suppresses the generation of electromagnetic noise.

[0018] Fig. 2 is an exploded perspective view showing a schematic structural configuration of the power conversion device 1 of this embodiment. As shown in Fig. 2, the power conversion device 1 of this embodiment includes an inverter case 2, an intelligent power module 3, a capacitor unit 4, and a power supply terminal 5. The power conversion device 1 may also include other components such as a reactor unit forming a step-up / step-down circuit and a DC-DC converter unit forming a DC-DC converter.

[0019] The inverter case 2 is a case that houses the intelligent power module 3, the capacitor unit 4, the power terminal 5, etc., and includes a center plate 2a and a case cover 2b. The center plate 2a and the case cover 2b are formed separately so as to be detachable. Note that in FIG. 2, the case cover 2b is shown separated upward from the center plate 2a. However, the installation posture of the power conversion device 1 is not particularly limited. In other words, the power conversion device 1 may be mounted on the vehicle so that the case cover 2b is located to the side of the center plate 2a.

[0020] The central plate 2a has a bottom wall portion to which the intelligent power module 3, the capacitor unit 4, and the power terminal 5 are fixed, and a side wall portion that surrounds the intelligent power module 3, the capacitor unit 4, and the power terminal 5. In other words, the central plate 2a is formed in a container shape that opens on the case cover 2b side. Such a central plate 2a is provided with a water channel as necessary, and is formed so as to be able to guide a coolant that cools the intelligent power module 3, the capacitor unit 4, and the power terminal 5.

[0021] The case cover 2b is fixed to the central plate 2a and covers the intelligent power module 3 and the capacitor unit 4. That is, the intelligent power module 3 and the capacitor unit 4 are exposed when the case cover 2b is detached from the central plate 2a.

[0022] Such an inverter case 2 is fixed to, for example, a housing (not shown) that covers the motor M or a gear case that houses a gear that transmits the power generated by the motor M to the outside. In such a case, for example, the center plate 2a is fastened to the motor housing or the gear case using a bolt (not shown) or the like. Note that, if the housing that covers the motor M has a space for accommodating the power conversion device 1, the case cover 2b may be omitted.

[0023] The inverter case 2 also holds a conductive line BU (see FIG. 1) that connects the power supply terminal 5 to the intelligent power module 3 and the capacitor unit 4, and a bus bar that forms part of the conductive line BU (see FIG. 1) (not shown) that connects the intelligent power module 3 to the motor M. Note that these bus bars are omitted in FIG. 1.

[0024] The intelligent power module 3 includes a power module 3a and a substrate unit 3b. The power module 3a is a module provided with a plurality of power devices D, which will be described later. In other words, the power module 3a forms an inverter circuit E with the plurality of power devices D.

[0025] The board unit 3b is arranged by being stacked on the power module 3a. The board unit 3b includes, for example, a gate driver board and an ECU (Electronic Control Unit) board. The gate driver board is a board provided with a gate driver that generates a drive signal for the inverter circuit E formed by the power module 3a. The ECU board is a board provided with an ECU that controls the gate driver board.

[0026] The capacitor unit 4 is a unit in which a capacitor element is housed. Such a capacitor unit 4 is connected to the power module 3a. Also, it is connected to a power supply terminal 5 by a bus bar (not shown). Such a capacitor unit 4 forms the capacitor C shown in FIG. 1.

[0027] The power supply terminal 5 is a connection portion of the power conversion device 1 of this embodiment with the battery B. A terminal portion of a harness (not shown) connected to the battery B is inserted into the inverter case 2. The power supply terminal 5 is connected to the battery B by being fastened to the harness.

[0028] Such a power supply terminal 5 includes a conductor plate holding portion 6, a conductor plate 7 (DC transmission conductor), and a noise filter unit 8. The conductor plate holding portion 6 is fastened to the center plate 2a of the inverter case 2 and holds the conductor plate 7. The conductor plate 7 is connected to the battery B and is a plate-shaped transmission path through which DC power flows. Two conductor plates 7 are provided. One conductor plate 7 is connected to the positive electrode side of the battery B. The other conductor plate 7 is connected to the negative electrode side of the battery B. These conductor plates 7 are arranged in parallel with a certain gap therebetween. Such conductor plates 7 form a part of the conductive line BU shown in FIG. 1. In other words, these conductor plates 7 are DC transmission conductors that connect the battery B and the power conversion circuit H.

[0029] The noise filter unit 8 has the above-mentioned two conductor plates 7 inserted therethrough, and suppresses large fluctuations in the current flowing through the conductor plates 7, thereby suppressing the generation of electromagnetic noise. Fig. 3 is a schematic exploded perspective view of the noise filter unit 8. As shown in this figure, the noise filter unit 8 includes a housing 10 and a core unit 11.

[0030] The housing 10 is fastened to the center plate 2a of the inverter case 2 and holds the core unit 11. As shown in Fig. 3, the housing 10 is provided with an accommodating portion 10a that accommodates the core unit 11. The accommodating portion 10a has a cylindrical peripheral wall portion 10b and an annular bottom wall portion 10c.

[0031] The peripheral wall portion 10b is formed in a cylindrical shape with its axis aligned in the extension direction (direction in which current flows) of the conductive plate 7. The bottom wall portion 10c is an annular portion provided so as to connect to one end of the peripheral wall portion 10b in the axial direction. The bottom wall portion 10c is formed in an annular shape centered on the axis of the peripheral wall portion 10b, and has an opening in the center through which the conductive plate 7 is inserted.

[0032] The storage section 10a is formed so that the core unit 11 can be inserted from the side of the peripheral wall section 10b where the bottom wall section 10c is not provided. Note that the moving direction when inserting the core unit 11 into the storage section 10a is referred to as the insertion direction. The direction toward which the insertion direction leads is referred to as the back side, and the side opposite the back side is referred to as the front side.

[0033] As shown in Fig. 3, flexible pieces 10d are provided at the upper and lower parts of the peripheral wall 10b. These flexible pieces 10d are strip-shaped portions formed so that the ends on the front side in the insertion direction leave a gap between them and the main body of the peripheral wall 10b, and the ends on the front side in the insertion direction are elastically deformable so as to move in the radial direction of the peripheral wall 10b. Each flexible piece 10d is provided with an opening 10e.

[0034] Further, a groove portion 10f is provided on each of the left and right portions of the peripheral wall portion 10b. Each groove portion 10f is provided on the inner wall surface of the peripheral wall portion 10b so as to be recessed radially outward from the axis of the peripheral wall portion 10b. Each groove portion 10f is provided linearly in parallel with the insertion direction, and is formed so that a protrusion portion 13f of the core unit 11 described below can be inserted from the front side in the insertion direction.

[0035] The flexible pieces 10d and the grooves 10f are provided in pairs. In other words, the flexible pieces 10d and the grooves 10f are provided in multiple numbers. The flexible pieces 10d and the grooves 10f are alternately arranged in the circumferential direction around the axis of the peripheral wall 10b as viewed from the insertion direction.

[0036] 4 is a schematic exploded perspective view of the core unit 11. As shown in this figure, the core unit 11 includes a core 12 and a core cover 13. The core 12 is made of a magnetic material and formed into a cylindrical shape. The core 12 is formed so that, when the core unit 11 is inserted into the storage portion 10a of the housing 10, the axis of the core 12 overlaps with the axis of the peripheral wall portion 10b.

[0037] The core cover 13 is a cylindrical hollow cover that houses the core 12. The core cover 13 is formed in a cylindrical shape centered on the axis L. Such a core cover 13 has an outer peripheral wall 13a, an inner peripheral wall 13b, a front end wall 13c, and a rear end wall 13d. The outer peripheral wall 13a is a wall portion that faces the outer peripheral surface of the core 12 from the radial outside of the core 12. The inner peripheral wall 13b is a wall portion that faces the inner peripheral surface of the core 12 from the radial inside of the core 12. The front end wall 13c is a wall portion that faces the end face of the core 12 on the front side in the insertion direction. The rear end wall 13d is a wall portion that faces the end face of the core 12 on the rear side in the insertion direction.

[0038] Such a core cover 13 is divided into a container body part in which the outer peripheral wall 13a, the inner peripheral wall 13b, and the front end wall 13c are integrated, and a lid part consisting of a rear end wall 13d. By removing the lid part from the container body part, the core 12 can be accommodated inside the container body part. The core 12 is bonded to the core cover 13 with an adhesive (not shown). Moreover, the lid part is bonded to the container body part with an adhesive (not shown).

[0039] The core cover 13 is provided with protrusions 13e protruding from the outer peripheral surface at the top and bottom. Each of these protrusions 13e is inserted into the opening 10e of the flexible piece 10d when the core unit 11 is accommodated in the accommodation section 10a. Each of the protrusions 13e is provided at a position where the end face on the front side in the insertion direction abuts against the edge of the opening 10e when inserted into the opening 10e in this manner. The protrusions 13e have an inclined surface formed by continuously decreasing the amount of protrusion from the front side toward the back side in the insertion direction.

[0040] Moreover, the width dimension of each protrusion 13e is substantially the same as the width dimension of the opening 10e within a range in which the protrusion 13e can be inserted into the opening 10e. Therefore, by inserting the protrusion 13e into the opening 10e, the core cover 13 is positioned in the circumferential direction about the axis L of the core cover 13 (i.e., the core unit 11). Furthermore, by inserting the protrusion 13e into the opening 10e, movement of the core cover 13 (i.e., the core unit 11) in the circumferential direction about the axis L is restricted.

[0041] When inserting the core cover 13 into the storage portion 10a, the core cover 13 is moved in the insertion direction relative to the housing 10. At this time, the flexible piece 10d is elastically deformed by the protrusion 13e so as to spread radially outward. When the protrusion 13e reaches the opening 10e, the flexible piece 10d is restored to its original shape. FIG. 5 is a schematic cross-sectional view including the flexible piece 10d and the protrusion 13e. FIG. 6 is a schematic enlarged perspective view including the flexible piece 10d and the protrusion 13e. As shown in these figures, the flexible piece 10d and the protrusion 13e are engaged with each other.

[0042] Such flexible piece 10d and protrusion 13e form a snap-fit ​​structure 20. The snap-fit ​​structure 20 functions as a movement restriction structure that restricts movement of the core cover 13 (i.e., the core unit 11) relative to the housing 10 in the direction opposite to the insertion direction when the core cover 13 is inserted into the housing 10. The power conversion device 1 of this embodiment has two such snap-fit ​​structures 20. These snap-fit ​​structures 20 are provided above and below the axis L of the core cover 13. In other words, a plurality of snap-fit ​​structures 20 are provided in the circumferential direction centered on the axis L.

[0043] Furthermore, the core cover 13 is provided with protrusions 13f protruding from the outer circumferential surface at the left and right parts. Each of these protrusions 13f is formed to protrude from the outer circumferential surface of the core cover 13 and extend linearly in the direction along the axis L. Each of the protrusions 13f is inserted into the groove 10f of the housing 10 when the core unit 11 is accommodated in the accommodation portion 10a.

[0044] Further, the width dimension of each of the protrusions 13f is substantially the same as the width dimension of the groove 10f within a range in which the protrusions 13f can be inserted into the groove 10f. Therefore, by inserting the protrusions 13f into the groove 10f, the movement of the core cover 13 (i.e., the core unit 11) in the circumferential direction about the axis L is restricted.

[0045] Such protrusions 13f and grooves 10f function as a rotation restriction structure 30 that restricts the core cover 13 from rotating in the circumferential direction about the axis L relative to the housing 10. In the power conversion device 1 of this embodiment, that is, the rotation restriction structure 30 has protrusions 13f that protrude from the circumferential surface of the core cover 13 and extend linearly in the direction along the axis L. The rotation restriction structure 30 also has grooves 10f that are recessed into the inner wall surface of the housing 10. The grooves 10f allow the protrusions 13f to be inserted or removed by moving the protrusions 13f in the direction along the axis L.

[0046] The power conversion device 1 of the present embodiment has two such rotation restriction structures 30. These rotation restriction structures 30 are provided on the left and right sides of the axis L of the core cover 13. In other words, a plurality of rotation restriction structures 30 are provided in the circumferential direction around the axis L.

[0047] Such snap-fit ​​structures 20 and rotation restriction structures 30 are provided in pairs and arranged alternately in the circumferential direction centered on the axis L. That is, in this embodiment, the snap-fit ​​structures 20 and the rotation restriction structures 30 are arranged alternately at intervals of 40° in the circumferential direction centered on the axis L.

[0048] Further, the noise filter unit 8 has an adhesive layer 14 as shown in Fig. 5. The adhesive layer 14 bonds the core cover 13 and the housing 10. In this embodiment, as shown in Fig. 5, the adhesive layer 14 is formed between the bottom wall portion 10c of the housing 10 and the inner end wall 13d of the core cover 13. In this manner, the housing 10 has the bottom wall portion 10c that faces the end face of the core cover 13 in the insertion direction. The adhesive layer 14 bonds the end face of the core cover 13 and the bottom wall portion 10c of the housing 10.

[0049] In such a power conversion device 1, when the core unit 11 is about to move forward in the insertion direction due to the vehicle traveling or the like, the load is received by the adhesive layer 14 and the snap-fit ​​structure 20. In addition, when the core unit 11 is about to move in the circumferential direction around the axis L due to the vehicle traveling or the like, the load is received by the snap-fit ​​structure 20 and the rotation restriction structure 30.

[0050] The noise filter unit 8 of the power conversion device 1 of the present embodiment includes a conductive plate 7 that connects the battery B and the power conversion circuit H. The noise filter unit 8 of the present embodiment includes a core 12, a core cover 13, a housing 10, and an adhesive layer 14. The core 12 is made of a cylindrical magnetic material. The core cover 13 is formed in a cylindrical shape to accommodate the core 12. The housing 10 is formed so that the core cover 13 can be inserted from a direction along the axis L of the core cover 13, and holds the inserted core cover 13. The adhesive layer 14 bonds the core cover 13 to the housing 10. The noise filter unit 8 of the present embodiment includes a snap-fit ​​structure 20. The snap-fit ​​structure 20 restricts the core cover 13 from moving relative to the housing 10 in a direction opposite to the insertion direction when the core cover 13 is inserted into the housing 10.

[0051] The noise filter unit 8 in this embodiment includes, in addition to the adhesive layer 14 that bonds the core cover 13 to the housing 10, a snap-fit ​​structure 20 that restricts the core cover 13 from moving relative to the housing 10 in the direction opposite to the insertion direction when the core cover 13 is inserted into the housing 10. Therefore, even if the adhesion between the core cover 13 and the housing 10 is peeled off, the core cover 13 can be prevented from coming off the housing 10. In addition, the snap-fit ​​structure 20 can bear a part of the load due to vibrations during driving of the vehicle, etc., and the load on the adhesive layer 14 can be reduced. Therefore, the adhesive force of the adhesive layer 14 can be prevented from decreasing. Therefore, in the noise filter unit 8 in this embodiment, in the noise filter unit 8 in which the core cover 13 that houses the core 12 is fixed to the housing 10, the core cover 13 can be prevented from coming off the housing 10.

[0052] Furthermore, in the noise filter unit 8 of this embodiment, the snap-fit ​​structure 20 has a protrusion 13e and a flexible piece 10d. The protrusion 13e protrudes from the outer circumferential surface of the core cover 13. The flexible piece 10d is provided on the housing 10. Furthermore, the flexible piece 10d has an opening 10e into which the protrusion 13e can be inserted.

[0053] The noise filter unit 8 of this embodiment can restrict the core cover 13 from moving toward the front in the insertion direction relative to the housing 10 by the snap-fit ​​structure 20. Moreover, the noise filter unit 8 of this embodiment can restrict the core cover 13 from moving toward the front in the insertion direction relative to the housing 10 by using the snap-fit ​​structure 20 with a simple structure.

[0054] Moreover, in the noise filter unit 8 of the present embodiment, a plurality of snap-fit ​​structures 20 are provided in the circumferential direction centered on the axis L. According to such a noise filter unit 8 of the present embodiment, the plurality of snap-fit ​​structures 20 can restrict the core cover 13 from moving toward the front side in the insertion direction relative to the housing 10. This can further reduce the load on the adhesive layer 14. Also, the load on each snap-fit ​​structure 20 can be reduced.

[0055] Moreover, the noise filter unit 8 in this embodiment includes a rotation restricting structure 30. The rotation restricting structure 30 restricts the core cover 13 from rotating in the circumferential direction about the axis L relative to the housing 10. The rotation restricting structure 30 is provided separately from the snap-fit ​​structure 20.

[0056] In the noise filter unit 8 of the present embodiment, the rotation restricting structure 30 can restrict the core cover 13 from rotating relative to the housing 10. This can reduce the load on the adhesive layer 14 when the core cover 13 rotates relative to the housing 10.

[0057] Furthermore, in the noise filter unit 8 of this embodiment, the rotation restricting structure 30 has a protrusion 13f and a groove 10f. The protrusion 13f protrudes from the circumferential surface of the core cover 13 and extends linearly in the direction along the axis L. The groove 10f is recessed into the inner wall surface of the housing 10. Furthermore, by moving the protrusion 13f in the direction along the axis L, the groove 10f allows the protrusion 13f to be inserted or removed.

[0058] According to the noise filter unit 8 of the present embodiment, it is possible to provide a simple rotation restricting structure 30. Therefore, the noise filter unit 8 of the present embodiment can restrict the core cover 13 from rotating relative to the housing 10 with a simple structure.

[0059] Moreover, in the noise filter unit 8 of the present embodiment, a plurality of rotation restricting structures 30 are provided in the circumferential direction centered on the axis L. According to the noise filter unit 8 of the present embodiment, the plurality of rotation restricting structures 30 can restrict the core cover 13 from rotating relative to the housing 10. As a result, the load on the adhesive layer 14 can be further reduced.

[0060] Moreover, in the noise filter unit 8 of the present embodiment, the snap-fit ​​structures 20 and the rotation restricting structures 30 are provided in multiple and alternate arrangements in the circumferential direction centered on the axis L. According to the noise filter unit 8 of the present embodiment, the snap-fit ​​structures 20 and the rotation restricting structures 30 can be evenly arranged around the axis L.

[0061] In the noise filter unit 8 of the present embodiment, the housing 10 has a bottom wall 10c facing an end face in the insertion direction of the core cover 13. An adhesive layer 14 bonds the end face of the core cover 13 and the bottom wall 10c of the housing 10.

[0062] According to the noise filter unit 8 of the present embodiment, the adhesive layer 14 can be disposed between the flat surfaces, and the adhesive layer 14 can be prevented from contacting the snap-fit ​​structure 20 and the rotation restricting structure 30. Therefore, the adhesive layer 14 can reliably bond the core cover 13 and the housing 10 together.

[0063] Moreover, the power conversion device 1 of this embodiment includes a power supply terminal 5 connected to the battery B. Moreover, the power conversion device 1 of this embodiment converts the power passing through the power supply terminal 5. Furthermore, the power supply terminal 5 includes a noise filter unit 8 that suppresses electromagnetic noise.

[0064] According to the noise filter unit 8 of this embodiment, since the noise filter unit 8 is provided, it is possible to prevent the core cover 13 from becoming detached from the housing 10.

[0065] Although the preferred embodiment of the present invention has been described above with reference to the attached drawings, it goes without saying that the present invention is not limited to the above embodiment. The shapes and combinations of the components shown in the above embodiment are merely examples, and various modifications can be made based on design requirements, etc., without departing from the spirit of the present invention.

[0066] FIG. 7 is a schematic diagram of a housing 10 provided in a modified example of the noise filter unit 8. As shown in this figure, a protrusion 10g for press-fitting the core cover 13 may be provided on the inner wall surface of the peripheral wall portion 10b of the housing 10. For example, a plurality of protrusions 10g are provided in the circumferential direction centered on the axis of the peripheral wall portion 10b. In FIG. 7, four protrusions 10g are provided. The core cover 13 is press-fitted into the range surrounded by these protrusions 10g. By press-fitting the core cover 13 into the housing 10 in this manner, each protrusion 10g is pressed against the core cover 13, and movement of the core cover 13 relative to the housing 10 can be more reliably suppressed.

[0067] The above embodiment can also be described as, for example, the following supplementary notes.

[0068] (Appendix 1) A noise filter unit through which a DC transmission conductor that connects a battery and a power conversion circuit is inserted, A cylindrical core made of a magnetic material; A cylindrical core cover that houses the core; a housing formed so that the core cover can be inserted from a direction along an axis of the core cover and which holds the inserted core cover; an adhesive layer that bonds the core cover and the housing; Equipped with A movement restriction structure is provided in a direction opposite to a direction in which the core cover is inserted into the housing, the movement restriction structure restricting the movement of the core cover relative to the housing. A noise filter unit comprising:

[0069] (Appendix 2) The movement restriction structure is a snap-fit ​​structure, The snap-fit ​​structure is A protrusion protruding from an outer circumferential surface of the core cover; a flexible piece that is provided on the housing and has an opening into which the protrusion can be inserted; have 2. The noise filter unit according to claim 1.

[0070] (Appendix 3) The noise filter unit according to any one of claims 2 to 6, wherein the snap-fit ​​structures are provided in a plurality of positions in a circumferential direction around the axis.

[0071] (Appendix 4) The noise filter unit described in any one of appendix 1 to 3, characterized in that a rotation restriction structure that restricts the core cover from rotating in a circumferential direction around the axis relative to the housing is provided separately from the movement restriction structure.

[0072] (Appendix 5) The rotation restriction structure includes: a protruding portion that protrudes from a peripheral surface of the core cover and extends linearly in a direction along the axis; a groove portion that is recessed into an inner wall surface of the housing, and into which the protrusion portion can be inserted and removed by moving the protrusion portion in a direction along the axis; have 5. The noise filter unit according to claim 4.

[0073] (Appendix 6) The noise filter unit according to any one of claims 1 to 5, wherein the rotation restriction structure is provided in a plurality of positions in a circumferential direction around the axis.

[0074] (Appendix 7) The noise filter unit according to any one of claims 4 to 6, wherein the movement restriction structure and the rotation restriction structure are provided in a plurality of positions alternately arranged in a circumferential direction around the axis.

[0075] (Appendix 8) the housing has an opposing wall that faces an end surface of the core cover in the insertion direction, The adhesive layer bonds the end surface of the core cover and the opposing wall of the housing. 8. The noise filter unit according to claim 1, wherein the noise filter unit comprises:

[0076] (Appendix 9) A power conversion device comprising a power supply terminal connected to a battery, the power conversion device converting power passing through the power supply terminal, 9. A power conversion device, wherein the power supply terminal comprises a noise filter unit according to any one of claims 1 to 8 for suppressing electromagnetic noise. [Explanation of symbols]

[0077] 1...power conversion device, 2...inverter case, 3...intelligent power module, 4...capacitor unit, 5...power terminal, 6...conductor plate holding portion, 7...conductor plate (DC transmission conductor), 8...noise filter unit, 10...housing, 10a...accommodating portion, 10b...peripheral wall portion, 10c...bottom wall portion (opposing wall), 10d...flexible piece, 10e...opening, 10f...groove portion, 10g...projection portion, 11...core unit, 12...core, 13...core cover, 13a...outer peripheral wall, 13b...inner peripheral wall, 13c...front end wall, 13d...rear end wall, 13e...projection portion, 13f...projection portion, 14...adhesive layer, 20...snap-fit ​​structure (movement restriction structure), 30...rotation restriction structure, B...battery, BU...conductive line, C...capacitor, D...power device, E...inverter circuit, F...noise filter, H...power conversion circuit, L...shaft core, M...motor

Claims

1. A noise filter unit through which a DC transmission conductor that connects a battery and a power conversion circuit is inserted, A cylindrical core made of a magnetic material; A cylindrical core cover that houses the core; a housing formed so that the core cover can be inserted from a direction along an axis of the core cover and which holds the inserted core cover; an adhesive layer that bonds the core cover and the housing; Equipped with A movement restriction structure is provided in a direction opposite to a direction in which the core cover is inserted into the housing, the movement restriction structure restricting the movement of the core cover relative to the housing. A noise filter unit comprising:

2. The movement restriction structure is a snap-fit ​​structure, The snap-fit ​​structure is A protrusion protruding from an outer circumferential surface of the core cover; a flexible piece that is provided on the housing and has an opening into which the protrusion can be inserted; have 2. The noise filter unit according to claim 1.

3. 3. The noise filter unit according to claim 2, wherein the snap-fit ​​structures are provided in a plurality in a circumferential direction around the shaft core.

4. The noise filter unit according to any one of claims 1 to 3, characterized in that a rotation restriction structure that restricts the core cover from rotating in a circumferential direction around the axis relative to the housing is provided separately from the movement restriction structure.

5. The rotation restriction structure includes: a protruding portion that protrudes from a peripheral surface of the core cover and extends linearly in a direction along the axis; a groove portion that is recessed into an inner wall surface of the housing, and into which the protrusion portion can be inserted and removed by moving the protrusion portion in a direction along the axis; have 5. The noise filter unit according to claim 4.

6. 6. The noise filter unit according to claim 5, wherein the rotation restricting structure is provided in a plurality in a circumferential direction around the shaft core.

7. 5. The noise filter unit according to claim 4, wherein the movement restricting structure and the rotation restricting structure are provided in a plurality of positions and arranged alternately in a circumferential direction about the shaft core.

8. the housing has an opposing wall that faces an end surface of the core cover in the insertion direction, The adhesive layer bonds the end surface of the core cover and the opposing wall of the housing.

4. The noise filter unit according to claim 1, wherein the first and second electrodes are arranged in a first direction.

9. A power conversion device comprising a power supply terminal connected to a battery, the power conversion device converting power passing through the power supply terminal, 4. A power conversion device, comprising: the power supply terminal comprising the noise filter unit according to claim 1, which suppresses electromagnetic noise.

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