Noise filter

Abstract

[Object] A noise filter is provided, in which a shield layer of a shielded cable and a ground portion can be electrically connected to each other, and the electrical connection state can be stably maintained. [Solution] A noise filter includes a magnetic core, a ground member, and a case. The case includes a first case component and a second case component. The ground member is in contact with a ground portion at the second contact portion. The second case component is provided with a pressing portion that comes into contact with the shielded cable and presses the shielded cable in a direction approaching the ground portion when the second case component is mounted on the first case component. When the shielded cable is pressed by the pressing portion, the shielded cable presses the ground member in a direction approaching the ground portion.

Description

Technical Field

[0001] The present disclosure relates to a noise filter.Background Art

[0002] A noise filter attached to a shielded cable is known (for example, see Patent Document 1 below). The noise filter described in Patent Document 1 below includes a split type magnetic core and a holder case made of a conductive resin or having conductive foil added thereto. By using such a noise filter, the magnetic core can be disposed inside a shield structure formed by a shield braid and a holder case of the shielded cable.Citation ListPatent Literature

[0003] Patent Document 1: Japanese Unexamined Patent Application Publication No. H06-310340 ASummary of InventionTechnical Problem

[0004] However, the above Patent Document 1 merely discloses a technique of disposing a magnetic core inside a shield structure. Therefore, Patent Document 1 does not disclose any technique for electrically connecting the shield structure as described above and a portion having a ground potential (hereinafter, also referred to as a ground portion).

[0005] In this regard, for example, when the holder case and the ground portion near the holder case are brought into contact with each other as described in Patent Document 1, the holder case and the ground portion can be electrically connected to each other. However, it is not clear whether or not the holder case and the ground portion can be maintained in a state of being in contact with each other appropriately by simply bringing the holder case and the ground portion into contact with each other. In particular, when the noise filter is disposed in an environment where vibration occurs, the contact state between the holder case and the ground portion is not stable due to the vibration of the noise filter, and it is difficult to stably maintain the electrical connection.

[0006] In one aspect of the present disclosure, it is desirable to provide a noise filter that can electrically connect a shield layer of a shielded cable and a ground portion and can stably maintain the electrical connection state.Solution to Problem

[0007] (1) One aspect of the present disclosure is a noise filter to be attached to a shielded cable, the noise filter including a magnetic core, a ground member, and a case. The magnetic core is a tubular magnetic body that includes a first split core and a second split core, each of which is made of a magnetic material, and is formed by combining the first split core and the second split core. The ground member is made of a conductive material, includes a first contact portion and a second contact portion, and is in contact with an exposed portion at the first contact portion, the exposed portion of a shield layer of the shielded cable being exposed to an outer peripheral side. The ground member electrically connects the shield layer and the ground portion by being in contact with a ground portion having the ground potential at the second contact portion. The case includes a first case component and a second case component, in which the second case component is configured to be mountable on the first case component, the first split core and the ground member are mounted on the first case component, and the second split core is mounted on the second case component. When the second case component is mounted on the first case component in a state where the shielded cable is disposed between the first case component and the second case component, the shielded cable is disposed so as to penetrate the case, the first split core and the second split core are disposed at positions surrounding the outer periphery of the shielded cable to constitute the magnetic core, and the ground member is configured to be in contact with the exposed portion at the first contact portion. The second case component is provided with a pressing portion that comes into contact with the shielded cable and presses the shielded cable in a direction approaching the ground portion when the second case component is mounted on the first case component, and when the shielded cable is pressed by the pressing portion, the shielded cable presses the ground member in a direction approaching the ground portion, so that a contact pressure between the second contact portion and the ground portion is high as compared with a case where the pressing portion is not provided.

[0008] According to the noise filter configured as described above, when the second case component is mounted on the first case component in a state where the shielded cable is disposed between the first case component and the second case component, the shielded cable is disposed at a position where the shielded cable penetrates the case. At this time, the first split core and the second split core are disposed at positions surrounding the outer periphery of the shielded cable to constitute the magnetic core. Therefore, the magnetic core can be attached to the outer periphery of the shielded cable without performing an operation of inserting one end of the shielded cable into the inner periphery of the magnetic core. Therefore, for example, the magnetic core can be attached to the wired shielded cable in a post-installation manner.

[0009] When the second case component is mounted on the first case component, the ground member is in contact with the exposed portion at the first contact portion. the exposed portion of the shield layer of the shielded cable being exposed to the outer peripheral side. The ground member is in contact with the ground portion at the second contact portion. Therefore, the shield layer and the ground portion can be electrically connected to each other via the ground member, and the potential of the shield layer can be made equal to the ground potential.

[0010] Further, when the second case component is mounted on the first case component, the pressing portion comes into contact with the shielded cable and presses the shielded cable in the direction approaching the ground portion. At this time, the shielded cable pressed by the pressing portion presses the ground member in the direction approaching the ground portion. Therefore, the contact pressure between the second contact portion and the ground portion is high as compared with a case where a similar pressing portion is not provided. Therefore, the electrical connection state between the second contact portion and the ground portion can be stably maintained as compared with the case where the similar pressing portion is not provided.

[0011] (2) In one aspect of the present disclosure, the first contact portion may be formed by an elastic clamping piece that is elastically deformed due to contact with the exposed portion and clamps the exposed portion by an elastic force generated in accordance with the elastic deformation.

[0012] According to the noise filter formed as described above, the first contact portion is formed by the elastic clamping piece as described above. Therefore, the elastic clamping piece is elastically deformed due to the contact with the exposed portion, and clamps the exposed portion by the elastic force generated in accordance with the elastic deformation. Therefore, compared to a case where the first contact portion is not elastically deformed, the contact pressure between the first contact portion and the exposed portion is high, and the electrical connection state between the first contact portion and the exposed portion can be stably maintained.

[0013] (3) In one aspect of the present disclosure, the second contact portion may be formed by an elastic pressing piece that is elastically deformed due to contact with the ground portion and presses the ground portion with the elastic force generated in accordance with the elastic deformation.

[0014] According to the noise filter formed as described above, the second contact portion is formed by the elastic pressing piece as described above. Therefore, the elastic pressing piece is elastically deformed due to the contact with the ground portion, and presses the ground portion by the elastic force generated in accordance with the elastic deformation. Therefore, compared to a case where the second contact portion is not elastically deformed, the contact pressure between the second contact portion and the ground portion is high, and the electrical connection state between the second contact portion and the ground portion can be stably maintained.

[0015] (4) In one aspect of the present disclosure, the magnetic core and the ground member may be disposed at positions adjacent to each other in an axial direction of the shielded cable. The first case component may have two through holes through which shaft portions of mounting screws pass when the first case component is mounted on a mounting target place. The two through holes may have the identical penetrating direction, and may be formed at positions having rotational symmetry such that the positions of the two through holes are interchangeable with each other by rotating the case by 180 degrees along a plane orthogonal to the penetrating direction. A passage through which the shielded cable passes in the case may be formed at a position having rotational symmetry such that, when the case is rotated 180 degrees so that the positions of the two through holes are interchanged with each other, a position of a central axis line of the passage does not change before and after the rotation.

[0016] According to the noise filter configured as described above, the positions of the two through holes can be interchanged by rotating the case by 180 degrees along the plane orthogonal to the penetrating direction of the through holes. At this time, the position of the central axis line of the passage through which the shielded cable passes can be maintained at a position that does not change before and after the rotation. Since the magnetic core and the ground member are disposed at positions adjacent to each other in the axial direction of the shielded cable, the positions of the magnetic core and the ground member are interchanged with each other before and after the rotation. Therefore, when the noise filter is rotated by 180 degrees, the position of the magnetic core and the position of the ground member can be interchanged without changing the position of the mounting screws or the position of the shielded cable.

[0017] (5) In one aspect of the present disclosure, the case may be provided with an engagement portion that engages the shielded cable from an outer peripheral side thereby to suppress relative displacement of the shielded cable with respect to the case when the second case component is mounted on the first case component after the shielded cable is disposed at a position to be the passage. The engagement portion may be provided at each of a position on the opposite side of the ground member side with the magnetic core interposed therebetween, a position between the magnetic core and the ground member, and a position on the opposite side of the magnetic core side with the ground member interposed therebetween.

[0018] According to the noise filter configured as described above, the engagement portion engages the shielded cable from the outer peripheral side, and thus it is possible to suppress relative displacement of the shielded cable with respect to the case. The engagement portion is provided at each of a position on the opposite side of the ground member side with the magnetic core interposed therebetween, a position between the magnetic core and the ground member, and a position on the opposite side of the magnetic core side with the ground member interposed therebetween. Therefore, the displacement of the shielded cable can be suppressed on each of the magnetic core side and the ground member side.Brief Description of Drawings

[0019] FIG. 1A is a perspective view of a noise filter in a state where a case is closed. FIG. 1B is a perspective view of the noise filter in a state where the case is opened. FIG. 2A is a plan view of the noise filter. FIG. 2B is a left-side view of the noise filter. FIG. 2C is a front view of the noise filter. FIG. 2D is a right-side view of the noise filter. FIG. 2E is a rear view of the noise filter. FIG. 2F is a bottom view of the noise filter. FIG. 3A is a perspective view of the noise filter in a state of being attached to a shielded cable and in a state where a case is closed. FIG. 3B is a perspective view of the noise filter in a state of being attached to the shielded cable and in a state where the case is opened. FIG. 4A is a front view of the noise filter in a state of being attached to the shielded cable. FIG. 4B is a cross-sectional view taken along line IVB-IVB in FIG. 4A. FIG. 5A is a perspective view of a ground member. FIG. 5B is a cross-sectional view taken along line VB-VB in FIG. 4. FIG. 6A is a plan view of the case in the open state. FIG. 6B is a perspective view of the case in the open state. Reference Signs List

[0020] 1 Noise filter, 3 Magnetic core, 3A First split core, 3B Second split core, 5 Ground member, 5A First contact portion, 5B Second contact portion, 7 Case, 7A First case component, 7B Second case component, 7C Hinge portion, 11 First engaging portion, 12 Second engaging portion, 13 Fixing portion, 15 Through hole, 21 Claw portion, 23 Groove portion, 25 Spring portion, 27 Snap portion, 29 Mounting hole, 31 Pressing portion, 33 Passage, 35 Engagement portionDescription of Embodiments

[0021] Next, the noise filter described above will be explained using an exemplary embodiment.Configuration of Noise Filter

[0022] As illustrated in FIGS. 1A, 1B, 2A, 2B, 2C, 2D, 2E, 2F, and 4B, a noise filter 1 includes a magnetic core 3, a ground member 5, and a case 7. The noise filter 1 is attached to a shielded cable 91 as illustrated in FIGS. 3A, 3B, and 4A.

[0023] As illustrated in FIGS. 1B and 3B, the magnetic core 3 includes a first split core 3A and a second split core 3B. The first split core 3A and the second split core 3B are each made of a magnetic material (e.g., ferrite). As illustrated in FIG. 4B, the magnetic core 3 is a tubular magnetic body formed by combining the first split core 3A and the second split core 3B. More specifically, the first split core 3A and the second split core 3B are semi-tubular objects obtained by splitting a tubular object into two by an imaginary plane passing through a central axis line C2 (see FIG. 2A and the like). These are combined to form the tubular magnetic core 3. Note that the central axis line C2 is a straight line that extends along a longitudinal direction of the shielded cable 91 and through which the center of the shielded cable 91 passes when the shielded cable 91 is disposed.

[0024] As illustrated in FIGS. 1A, 1B, 3A, 3B, 5A, and 5B, the ground member 5 includes a first contact portion 5A and a second contact portion 5B. The ground member 5 is made of a conductive material (copper alloy in the present embodiment). As illustrated in FIG. 5B, the shielded cable 91 exemplified in the present embodiment has a structure in which four signal lines 93 are bundled, the outer periphery thereof is covered with a shield layer 95, and the outer periphery thereof is further covered with a sheath 97. Note that the first contact portion 5A and the second contact portion 5B are electrically continuous with each other (in other words, electrically connected to each other).

[0025] As illustrated in FIGS. 3B and 5B, the shielded cable 91 is provided with an exposed portion 95A in which the shield layer 95 is exposed to the outer peripheral side by partially peeling off the sheath 97. The ground member 5 is in contact with the exposed portion 95A of the shield layer 95 at the first contact portion 5A. As illustrated in FIG. 5B, the ground member 5 is in contact with a ground portion 99 having the ground potential at the second contact portion 5B. Thus, the ground member 5 electrically connects the shield layer 95 and the ground portion 99. Note that the ground portion 99 is at least a part of a conductive member (for example, a mounting target place described later) disposed outside the noise filter 1.

[0026] As illustrated in FIG. 5B, the first contact portion 5A is formed as an elastic clamping piece that clamps the exposed portion 95A of the shield layer 95 from both sides in a front-rear direction in the figure. The elastic clamping piece is shaped to form a gap narrower than the diameter of the exposed portion 95A of the shield layer 95 in an unloaded state. When the exposed portion 95A of the shield layer 95 is introduced into the gap, the elastic clamping piece is elastically deformed in a direction in which the gap is widened due to contact with the exposed portion 95A, and clamp the exposed portion 95A using an elastic force generated in accordance with the elastic deformation.

[0027] As illustrated in FIG. 5B, the second contact portion 5B is formed as an elastic pressing piece that presses the ground portion 99 downward in the figure. The elastic pressing piece is elastically deformed due to the contact with the ground portion 99, and presses the ground portion 99 by using the elastic force generated in accordance with the elastic deformation.

[0028] The case 7 includes a first case component 7A and a second case component 7B. In the case of the present embodiment, the first case component 7A and the second case component 7B are formed to be openable and closable by being coupled via three hinge portions 7C as illustrated in FIGS. 1A, 1B, 2E, 3A, 3B, 4B, and 5B. As illustrated in FIGS. 4A and 4B, three first engaging portions 11 are provided on the first case component 7A, and three second engaging portions 12 are provided on the second case component 7B.

[0029] When the first case component 7A and the second case component 7B are closed as illustrated in FIG. 1A, the three first engaging portions 11 and the corresponding three second engaging portions 12 are engaged with each other in a one-to-one manner, and the first case component 7A and the second case component 7B are maintained in a closed state. When the three first engaging portions 11 and the three second engaging portions 12 are disengaged, the first case component 7A and the second case component 7B can be opened as illustrated in FIG. 1B.

[0030] In the case of the present embodiment, the first case component 7A and the second case component 7B are integrally molded with the hinge portion 7C using a resin material (for example, polyamide). However, in order to make the case 7 openable and closable, it is sufficient that the second case component 7B is configured to be attachable to and detachable from the first case component 7A. Therefore, it is optional whether or not the hinge portion 7C is provided.

[0031] For example, instead of the hinge portion 7C, an engagement mechanism equivalent to the first engaging portion 11 and the second engaging portion 12 described above may be provided, and whereby the second case component 7B can be attached to and detached from the first case component 7A. That is, as long as the second case component 7B is configured to be mountable on the first case component 7A, the first case component 7A and the second case component 7B may be an integrally molded product that is connected via the hinge portion 7C, or may be separate resin-molded products that are not connected.

[0032] The first case component 7A is configured to be mountable on a mounting target place. In the case of the present embodiment, the mounting target place is the above-described ground portion 99 (see FIG. 5B), and for example, metal frames, panels, chassis, and the like are used. In the case of the present embodiment, two fixing portions 13 are provided on the first case component 7A as illustrated in FIGS. 1A, 2A, and 2F. A through hole 15 is formed in each of the fixing portions 13.

[0033] When the first case component 7A is mounted on the mounting target place, for example, a female screw (that is, a screw hole) is formed in advance in the mounting target place. Then, the shaft portion of a male screw (for example, a hexagon head bolt) passes through the through hole 15 of the fixing portion 13, the male screw is screwed into the female screw formed in the mounting target place, and the male screw is fastened, whereby the first case component 7A can be fixed to the mounting target place.

[0034] Alternatively, for example, a male screw (that is, a screw shaft) is erected in advance at the mounting target place. Then, the first case component 7A is disposed at the mounting target place so that the male screw passes through the through hole 15 of the fixing portion 13, a female screw (for example, a hexagonal nut) is screwed to the male screw, and the female screw is fastened, whereby the first case component 7A can be fixed to the mounting target place.

[0035] As illustrated in FIGS. 1B and 3B, the first split core 3A and the ground member 5 are mounted on the first case component 7A.

[0036] As illustrated in FIGS. 6A and 6B, three claw portions 21 are formed on the first case component 7A, and as illustrated in FIG. 4B, the claw portions 21 are hooked on groove portions 23 of the first split core 3A, whereby the first split core 3A is mounted on the first case component 7A. As illustrated in FIGS. 2F and 4B, two spring portions 25 are provided on the first case component 7A. The two spring portions 25 are elastically deformed due to the contact with the first split core 3A, and the first split core 3A is biased upward in FIG. 4B by the elastic force generated in accordance with the elastic deformation.

[0037] As illustrated in FIGS. 1B and 3B, the second split core 3B is mounted on the second case component 7B. As illustrated in FIGS. 6A and 6B, the three claw portions 21 are formed on the second case component 7B, and as illustrated in FIG. 4B, the claw portions 21 are hooked on the groove portions 23 of the second split core 3B, whereby the second split core 3B is mounted on the second case component 7B. As illustrated in FIGS 2A and 4B, the two spring portions 25 are provided on the second case component 7B. The two spring portions 25 are elastically deformed due to the contact with the second split core 3B, and the second split core 3B is biased downward in FIG. 4B by the elastic force generated in accordance with the elastic deformation.

[0038] With these configurations, the first split core 3A and the second split core 3B are biased in a direction in which the contact pressure therebetween increases, and the magnetic characteristics of the magnetic core 3 are improved.

[0039] As illustrated in FIGS. 5B and 6A, the first case component 7A is provided with a snap portion 27. The snap portion 27 is inserted into a mounting hole 29 (see FIGS. 5A and 5B) of the ground member 5, and thus the ground member 5 is mounted on the first case component 7A.

[0040] When the second case component 7B is mounted on the first case component 7A in a state where the shielded cable 91 is disposed between the first case component 7A and the second case component 7B as illustrated in FIG. 3B, the noise filter 1 is attached to the outer periphery of the shielded cable 91 as illustrated in FIG. 3A.

[0041] When the second case component 7B is mounted on the first case component 7A, the shielded cable 91 is disposed at a position penetrating the case 7 as illustrated in FIG. 3A. Further, as illustrated in FIG. 4B, the first split core 3A and the second split core 3B are disposed at positions surrounding the outer periphery of the shielded cable 91 to constitute the magnetic core 3. Further, as illustrated in FIG. 5B, the ground member 5 is in contact with the exposed portion 95A of the shield layer 95 at the first contact portion 5A. The magnetic core 3 and the ground member 5 are disposed at positions adjacent to each other in an axial direction of the shielded cable 91.

[0042] In the case of the present embodiment, when the first case component 7A is mounted on the mounting target place, the ground member 5 comes into contact with the ground portion 99 at the second contact portion 5B as illustrated in FIG. 5B. In the case of the present embodiment, the mounting target place itself functions as the ground portion 99. However, a part of the mounting target place may be configured to function as the ground portion 99.

[0043] As illustrated in FIGS. 1B, 3B, and 5B, the second case component 7B is provided with a pressing portion 31. When the second case component 7B is mounted on the first case component 7A, the pressing portion 31 comes into contact with the shielded cable 91 and presses the shielded cable 91 in a direction approaching the ground portion 99 as illustrated in FIG. 5B. When the shielded cable 91 is pressed by the pressing portion 31, the shielded cable 91 presses the ground member 5 in the direction approaching the ground portion 99. As such, when the pressing portion 31 is provided, the contact pressure between the second contact portion 5B and the ground portion 99 is high as compared with the case where the pressing portion 31 is not provided.

[0044] Further, when the shielded cable 91 is disposed in a passage 33 (see FIGS. 2B and 2D) penetrating the case 7, the shielded cable 91 is sandwiched between the pressing portion 31 and the ground member 5. Accordingly, the shielded cable 91 is disposed straight at the position of the central axis line C2 illustrated in FIGS. 2A, 2C, 2E, and 2F between the pressing portion 31 and the ground member 5. Therefore, unlike the case where there is no configuration corresponding to the pressing portion 31, even when the shielded cable 91 receives an elastic force from the first contact portion 5A, the shielded cable 91 can be prevented from bending upward in the figure at the place where the elastic force is received. Therefore, it is possible to prevent an excessive load from being applied to the shielded cable 91 due to the occurrence of such bending.

[0045] The two through holes 15 provided in the first case component 7A are formed at positions having rotational symmetry such that the positions of the two through holes 15 can be interchanged with each other by rotating the case 7 by 180 degrees along a plane orthogonal to the penetrating direction (the vertical direction in the figure). To be more specific, the two through holes 15 have rotational symmetry such that the positions of the two through holes 15 are interchanged with each other when the case 7 is rotated 180 degrees about the axis line C1 illustrated in FIGS 2B, 2C, 2D, and 2E. That is, the positions having rotational symmetry are a plurality of positions on the same circumference around the axis line (here, C1).

[0046] The passage 33 (see FIGS. 2B and 2D) through which the shielded cable 91 in the case 7 penetrates is formed at a position having rotational symmetry such that when the case 7 is rotated by 180 degrees so that the positions of the two through holes 15 are interchanged with each other, the position of the central axis line C2 of the passage 33 illustrated in FIGS. 2A, 2C, 2E, and 2F does not change before and after the rotation.

[0047] Therefore, even when the case 7 is rotated by 180 degrees about the axis line C1 as the rotation center to interchange the positions of the two through holes 15, the noise filter 1 can be mounted on the mounting target place without changing the positions of the mounting screws or the position of the shielded cable 91. Therefore, when the noise filter 1 is rotated by 180 degrees, the position of the magnetic core 3 and the position of the ground member 5 can be interchanged without changing the positions of the mounting screws or the position of the shielded cable 91.

[0048] As illustrated in FIGS 6A and 6B, the case 7 is provided with an engagement portion 35. The engagement portion 35 engages the shielded cable 91 from the outer peripheral side when the second case component 7B is mounted on the first case component 7A after the shielded cable 91 is disposed at a position to be the passage 33 (see FIGS. 2B and 2D). Thus, the engagement portion 35 suppresses the relative displacement of the shielded cable 91 with respect to the case 7.

[0049] In the case of the present embodiment, as illustrated in FIGS. 6A and 6B, the engagement portion 35 is provided at a position on the opposite side of the ground member 5 side with the magnetic core 3 interposed therebetween, a position between the magnetic core 3 and the ground member 5, and a position on the opposite side of the magnetic core 3 side with the ground member 5 interposed therebetween. When the engagement portion 35 is provided at such a position, the displacement of the shielded cable 91 can be suppressed on each of the magnetic core 3 side and the ground member 5 side.Beneficial Effects

[0050] According to the noise filter 1 configured as described above, when the second case component 7B is mounted on the first case component 7A in a state where the shielded cable 91 is disposed between the first case component 7A and the second case component 7B, the shielded cable 91 is disposed at a position where the shielded cable 91 penetrates the case 7. At this time, the first split core 3A and the second split core 3B are disposed at positions surrounding the outer periphery of the shielded cable 91 to constitute the magnetic core 3. Therefore, the magnetic core 3 can be attached to the outer periphery of the shielded cable 91 without performing an operation of inserting one end of the shielded cable 91 into the inner periphery of the magnetic core 3. Therefore, for example, the magnetic core 3 can be attached to the wired shielded cable 91 in a post-installation manner.

[0051] When the second case component 7B is mounted on the first case component 7A, the ground member 5 is in contact with the exposed portion 95A at the first contact portion 5A, the exposed portion 95A of the shield layer 95 of the shielded cable 91 being exposed to the outer peripheral side. The ground member 5 is in contact with the ground portion 99 at the second contact portion 5B. Therefore, the shield layer 95 and the ground portion 99 can be electrically connected to each other via the ground member 5, and the potential of the shield layer 95 can be made equal to the ground potential.

[0052] Further, when the second case component 7B is mounted on the first case component 7A, the pressing portion 31 comes into contact with the shielded cable 91 and presses the shielded cable 91 in the direction approaching the ground portion 99. At this time, the shielded cable 91 pressed by the pressing portion 31 presses the ground member 5 in a direction approaching the mounting target place. Therefore, the contact pressure between the second contact portion 5B and the ground portion 99 is high as compared with the case where the similar pressing portion 31 is not provided. Therefore, the electrical connection state between the second contact portion 5B and the ground portion 99 can be stably maintained as compared with the case where the similar pressing portion 31 is not provided.

[0053] In the case of the present embodiment, the first contact portion 5A is formed as the elastic clamping piece as described above. Therefore, compared to a case where the first contact portion 5A is not elastically deformed, the contact pressure between the first contact portion 5A and the exposed portion 95A is high, and the electrical connection state between the first contact portion 5A and the exposed portion 95A can be stably maintained.

[0054] In the case of the present embodiment, the second contact portion 5B is formed as the elastic pressing piece as described above. Therefore, compared to a case where the second contact portion 5B is not elastically deformed, the contact pressure between the second contact portion 5B and the ground portion 99 is high, and the electrical connection state between the second contact portion 5B and the ground portion 99 can be stably maintained.

[0055] In the case of the present embodiment, when the noise filter 1 is rotated by 180 degrees, the position of the magnetic core 3 and the position of the ground member 5 can be switched without changing the positions of the mounting screws or the position of the shielded cable 91.

[0056] In the case of the present embodiment, since the engagement portion 35 is provided at the position as described above, the displacement of the shielded cable 91 can be suppressed on each of the magnetic core 3 side and the ground member 5 side.Other Embodiments

[0057] While the noise filter 1 has been described above with reference to the exemplary embodiments, the embodiments described above are merely examples as an aspect of the present disclosure. That is, the present disclosure is not limited to the exemplary embodiments described above, and can be carried out in various forms without departing from the technical concept of the present disclosure.

[0058] For example, in the above embodiment, the elastic pressing piece constituting the second contact portion 5B has a shape extending diagonally forward down and diagonally rearward down in the figure, but the elastic pressing piece may have a shape extending diagonally leftward down and diagonally rightward down in the figure.

[0059] In the above embodiment, one magnetic core 3 and one ground member 5 are provided in the case 7, but two or more magnetic cores 3 and two or more ground members 5 may be provided. In this case, the magnetic cores 3 and the ground members 5 may be arranged in any order.

[0060] In addition, in the above-described embodiment, the magnetic core 3 is a tubular magnetic body, but as is clear from FIG. 4B, the tubular shape referred to in the present specification is not limited to a circular cylindrical shape in a strict sense, and may be any shape as long as the shielded cable 91 can penetrate the inner periphery of the magnetic core 3. For example, in the case of the above-described embodiment, the outer periphery of the magnetic core 3 includes a portion formed by a curved surface, a portion formed by a flat surface, a portion in which the groove portion 23 is formed, and the like, as illustrated in FIG. 4B. Such a shape of the magnetic core 3 also corresponds to an example of the tubular shape in the present specification.

[0061] That is, in the tubular magnetic core 3 referred to in the present specification, the shapes of the outer peripheral surface and the inner peripheral surface are not limited to specific shapes. Therefore, the shapes of the outer peripheral surface and the inner peripheral surface of the magnetic core 3 may be any of a shape in which the cross-sectional shape perpendicular to the axial direction of the magnetic core 3 is a circle, a shape in which the cross-sectional shape is a polygon such as a quadrangle or a hexagon, and a shape in which the cross-sectional shape is different from a circle or a polygon.

[0062] Further, the first split core 3A and the second split core 3B of the above embodiment are formed to have the same shape, but the first split core 3A and the second split core 3B may have different shapes. For example, the magnetic core may be formed in a rectangular tube shape having a substantially rectangular cross-sectional shape perpendicular to the axial direction. In this case, three sides of the substantially rectangular shape may be formed by the first split core, and one side of the substantially rectangular shape may be formed by the second split core.

[0063] In the above embodiment, the mounting target place of the first case component 7A is configured to function as the ground portion 99, but the mounting target place of the first case component 7A and the ground portion 99 may be separately provided. For example, in the above embodiment, the two fixing portions 13 have a shape assuming that the mounting target place is located below the noise filter 1 in the figure, but may have a shape assuming that the mounting target place is located on the front side or the rear side in the figure. In this case, a metal component (for example, a metal bracket) or the like that functions as the ground portion 99 may be disposed below the noise filter 1 in the figure, separately from the mounting target place.

[0064] Note that a plurality of functions implemented by one component illustrated in the above embodiment may be implemented by a plurality of components. One function implemented by one component illustrated in the above embodiment may be implemented by a plurality of components. A plurality of functions implemented by a plurality of components illustrated in the above embodiment may be implemented by one component. One function implemented by a plurality of components illustrated in the above embodiment may be implemented by one component. Additionally, a portion of the configurations exemplified in the embodiments described above may be omitted.Technical Concept Disclosed in Specification[Item 1]

[0065] A noise filter that is configured to be attached to a shielded cable including a shield layer and an exposed portion configured to expose the shield layer to an outer peripheral side, the noise filter including: a magnetic core that is a tubular magnetic body including a first split core and a second split core each made of a magnetic material, the magnetic core being formed by combining the first split core and the second split core; a ground member that is made of a conductive material, includes a first contact portion and a second contact portion, and electrically connects the shield layer and a ground portion having a ground potential by being in contact with the exposed portion of the shielded cable at the first contact portion and being in contact with the ground portion at the second contact portion; and a case including a first case component and a second case component, in which the second case component is configured to be mountable on the first case component, the first split core and the ground member are mounted on the first case component, and the second split core is mounted on the second case component, in which when the second case component is mounted on the first case component in a state where the shielded cable is disposed between the first case component and the second case component, the shielded cable is disposed so as to penetrate the case, the first split core and the second split core are disposed so as to surround an outer periphery of the shielded cable to constitute the magnetic core, and the ground member is configured to be in contact with the exposed portion at the first contact portion, the second case component is provided with a pressing portion, the pressing portion being configured to be in contact with the shielded cable and press the shielded cable in a direction approaching the ground portion when the second case component is mounted on the first case component, and when the shielded cable is pressed by the pressing portion, the shielded cable presses the ground member in a direction approaching the ground portion, so that a contact pressure between the second contact portion and the ground portion is high as compared with a case in which the pressing portion is not provided. [Item 2]

[0066] The noise filter according to item 1, in which the first contact portion is formed by an elastic clamping piece that is elastically deformed due to contact with the exposed portion and clamps the exposed portion by an elastic force generated in accordance with the elastic deformation.[Item 3]

[0067] The noise filter according to item 1 or 2, in which the second contact portion is formed by an elastic pressing piece that is elastically deformed due to contact with the ground portion and presses the ground portion by an elastic force generated in accordance with the elastic deformation.[Item 4]

[0068] The noise filter according to any one of items 1 to 3, in which the magnetic core and the ground member are disposed at positions adjacent to each other in an axial direction of the shielded cable, the first case component includes two through holes through which shaft portions of mounting screws pass when the first case component is mounted on a mounting target place, the two through holes have an identical penetrating direction and are formed at positions having rotational symmetry such that the positions of the two through holes are interchangeable with each other by rotating the case by 180 degrees along a plane orthogonal to the penetrating direction, and a passage through which the shielded cable passes in the case is formed at a position having rotational symmetry such that, when the case is rotated 180 degrees so that the positions of the two through holes are interchanged with each other, a position of a central axis line of the passage does not change before and after the rotation. [Item 5]

[0069] The noise filter according to item 4, in which the case is provided with an engagement portion that engages the shielded cable from an outer peripheral side to suppress relative displacement of the shielded cable with respect to the case when the second case component is mounted on the first case component after the shielded cable is disposed at a position to be the passage, and the engagement portion is provided at each of a position on the opposite side of the ground member side with the magnetic core interposed therebetween, a position between the magnetic core and the ground member, and a position on the opposite side of the magnetic core side with the ground member interposed therebetween.

Claims

1. A noise filter that is configured to be attached to a shielded cable including a shield layer and an exposed portion configured to expose the shield layer to an outer peripheral side, the noise filter comprising: a magnetic core that is a tubular magnetic body including a first split core and a second split core each made of a magnetic material, the magnetic core being formed by combining the first split core and the second split core; a ground member that is made of a conductive material, includes a first contact portion and a second contact portion, and electrically connects the shield layer and a ground portion having a ground potential by being in contact with the exposed portion of the shielded cable at the first contact portion and being in contact with the ground portion at the second contact portion; and a case including a first case component and a second case component, in which the second case component is configured to be mountable on the first case component, the first split core and the ground member are mounted on the first case component, and the second split core is mounted on the second case component, wherein when the second case component is mounted on the first case component in a state where the shielded cable is disposed between the first case component and the second case component, the shielded cable is disposed so as to penetrate the case, the first split core and the second split core are disposed so as to surround an outer periphery of the shielded cable to constitute the magnetic core, and the ground member is configured to be in contact with the exposed portion at the first contact portion, the second case component is provided with a pressing portion, the pressing portion being configured to be in contact with the shielded cable and press the shielded cable in a direction approaching the ground portion when the second case component is mounted on the first case component, and when the shielded cable is pressed by the pressing portion, the shielded cable presses the ground member in a direction approaching the ground portion, so that a contact pressure between the second contact portion and the ground portion is high as compared with a case in which the pressing portion is not provided.

2. The noise filter according to claim 1, wherein the first contact portion is formed by an elastic clamping piece that is elastically deformed due to contact with the exposed portion and clamps the exposed portion by an elastic force generated in accordance with the elastic deformation.

3. The noise filter according to claim 1 or 2, wherein the second contact portion is formed by an elastic pressing piece that is elastically deformed due to contact with the ground portion and presses the ground portion by an elastic force generated in accordance with the elastic deformation.

4. The noise filter according to claim 1 or 2, wherein the magnetic core and the ground member are disposed at positions adjacent to each other in an axial direction of the shielded cable, the first case component includes two through holes through which shaft portions of mounting screws pass when the first case component is mounted on a mounting target place, the two through holes have an identical penetrating direction and are formed at positions having rotational symmetry such that the positions of the two through holes are interchangeable with each other by rotating the case by 180 degrees along a plane orthogonal to the penetrating direction, and a passage through which the shielded cable passes in the case is formed at a position having rotational symmetry such that, when the case is rotated 180 degrees so that the positions of the two through holes are interchanged with each other, a position of a central axis line of the passage does not change before and after the rotation.

5. The noise filter according to claim 4, wherein the case is provided with an engagement portion that engages the shielded cable from an outer peripheral side to suppress relative displacement of the shielded cable with respect to the case when the second case component is mounted on the first case component after the shielded cable is disposed at a position to be the passage, and the engagement portion is provided at each of a position on an opposite side of the ground member side with the magnetic core interposed therebetween, a position between the magnetic core and the ground member, and a position on an opposite side of the magnetic core side with the ground member interposed therebetween.

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