Wiring structure of an electrical device

Abstract

The present application provides a wiring structure for an electrical device that can stabilize the height of the overhang of a busbar from a control board. The wiring structure of the electrical device comprises: a connector (4, 4a, 4b) attached to a housing (2) and having an outer connector housing (4a2, 4b2) and an inner connector housing (4a1, 4b1); a busbar (7) one side of which is located in the outer connector housing (4a2, 4b2) of the connector (4a, 4b) and the other side extends to the outside of the inner connector housing (4a1, 4b1) of the connector (4a, 4b); and a control board (3) through which the other side of the busbar (7) passes.The wiring structure of the electrical device then includes a seal (6) which is fitted by insertion between an outer circumferential section (4c) of the connector (4) and an inner circumferential section (2a) of the housing (2) which faces the outer circumferential section (4c) of the connector (4) and seals a gap between the connector (4) and the housing (2).

Description

Wiring structure of electrical equipment

[0001] The present application relates to a wiring structure for an electric device.

[0002] Conventional connectors use a sealing member to prevent water from entering the internal housing space that houses the ferrite core and to prevent water from adhering to the terminals. The bus bar is press-fitted into the inner housing to secure it, and the ferrite core is provided with a bus bar insertion hole through which the bus bar is inserted. The inner and outer housings are assembled by receiving a locking portion of the inner housing in a locking hole in the outer housing. The sealing member is disposed between the outer and inner housings and provides axial and planar sealing, preventing water from entering from outside the housing (see Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2020-113478

[0004] The wiring structure for electrical equipment described in the above-mentioned conventional Patent Document 1 is a structure in which the connector seals in the axial and planar directions to waterproof the space between separate structures. However, due to the planar sealing, the bus bar support part of the inner housing receives a reaction force caused by the sealing member being compressed in the planar direction, which causes a problem in that the positional accuracy of the bus bar is unstable.

[0005] Furthermore, the bus bar of the connector is electrically connected to the control board inside the housing of the wiring structure of the electrical device by soldering. As in the case of the conventional connector seal structure of the wiring structure of the electrical device described in Patent Document 1, if the connector receives a reaction force caused by the seal member being compressed in the surface direction, when the bus bar of the connector is inserted into the through hole of the control board and soldered, the reaction force of the surface seal at the surface seal portion between the housing and the connector pushes back the connector, causing an unstable amount of protrusion of the connector bus bar from the through hole in the control board, which affects the solderability.

[0006] For bus bars that extend in the direction in which the reaction force of the face seal is generated, it is necessary to consider ways to stabilize the amount by which the bus bar protrudes from the through hole in the control board and solve the problem of deterioration in solderability.

[0007] The present application discloses a technique for solving the above-mentioned problems, and its purpose is to provide a wiring structure for an electrical device that can stabilize the amount of bus bar protrusion from a control board.

[0008] The wiring structure of an electrical device disclosed in the present application is a wiring structure of an electrical device that includes a connector fixed to a housing and having a connector housing composed of an outer connector housing and an inner connector housing, a bus bar having one side disposed in the outer connector housing of the connector and the other side extending outside the inner connector housing of the connector, and a control board held in the housing and through which the other side of the bus bar is inserted, and is provided with a gasket that is inserted between the outer periphery of the connector and the inner periphery of the housing opposite the outer periphery of the connector, and seals the gap between the connector and the housing.

[0009] According to the wiring structure of the electrical device disclosed in the present application, a gasket that seals the gap between the connector and the housing is inserted between the outer periphery of the connector and the inner periphery of the housing that faces the outer periphery of the connector, thereby stabilizing the amount of protrusion of the bus bar from the control board.

[0010] 1 is a perspective view showing the wiring structure of an electric device according to embodiment 1. FIG. 2 is a perspective view showing the wiring structure of an electric device according to embodiment 1 as viewed from the back side of FIG. 1. FIG. 3 is a front view showing the wiring structure of an electric device according to embodiment 1. FIG. 4 is a cross-sectional view taken along line A-A in FIG. 3 of the wiring structure of an electric device according to embodiment 1. FIG. 5 is a front view showing a connector in the wiring structure of an electric device according to embodiment 1. FIG. 6 is a cross-sectional view corresponding to line A-A in FIG. 3 of the wiring structure of an electric device according to embodiment 2. FIG. 7 is an enlarged view of part B in FIG. 6 of the wiring structure of an electric device according to embodiment 2. FIG. 8 is a front view showing the wiring structure of an electric device according to embodiment 3. FIG. 9 is a cross-sectional view taken along line C-C in FIG. 8 of the wiring structure of an electric device according to embodiment 3. FIG. 10 is an enlarged view of part D in FIG. 9 of the wiring structure of an electric device according to embodiment 3.

[0011] Embodiment 1. Hereinafter, embodiment 1 of the present application will be described with reference to Figures 1 to 5, with the same or equivalent members and parts in each figure being denoted by the same reference numerals. Figure 1 is a perspective view showing the wiring structure of an electrical device according to embodiment 1. Figure 2 is a perspective view showing the wiring structure of an electrical device according to embodiment 1 as viewed from the back side of Figure 1. Figure 3 is a front view showing the wiring structure of an electrical device according to embodiment 1. Figure 4 is a cross-sectional view of the wiring structure of an electrical device according to embodiment 1 taken along line A-A in Figure 3. Figure 5 is a front view showing a connector in the wiring structure of an electrical device according to embodiment 1.

[0012] The wiring structure for an electrical device according to the first embodiment is a structure that transmits and receives signals to and from the outside and controls power using the signals, and is characterized in that the housing and connector are waterproofed with an axial seal. Examples of wiring structures for electrical devices include devices that require a waterproof structure, such as a power conversion device, and that control power to a desired level using a control board inside the structure.

[0013] Conventional connectors waterproof the gap between the inner and outer housings with a surface seal and an axial seal. However, because the surface seal also seals, a reaction force is generated from the sealing material in the direction in which the bus bar extends, making the position of the bus bar unstable in the direction in which it extends.

[0014] The connector attached to the wiring structure of the electrical device of this application uses a bus bar to send and receive electrical signals, and the bus bar is inserted into a through hole in the control board inside the housing and soldered to provide electrical contact.

[0015] Connectors that send and receive electrical signals have thin bus bars adjacent to each other at a short pitch, and it is known that solder bridges can occur between adjacent bus bars depending on the length of the bus bars that protrude from the through holes in the control board.

[0016] In the case of a face seal structure like the background art, the connector is pushed back by the reaction force of the packing, and the position of the tip of the bus bar is likely to shift in the direction of the reaction force, making it difficult to control the length of the bus bar that protrudes from the through hole.

[0017] The structure of the present application uses a shaft packing and generates a reaction force perpendicular to the direction in which the bus bar protrudes from the through hole, which stabilizes the length of the bus bar protruding from the through hole and improves solderability.

[0018] A wiring structure 1 for an electrical device according to a first embodiment of the present invention will be described with reference to Figures 1 to 4. Connector 4 is fixed to housing 2 with screws and is composed of two connectors, 4a and 4b, with connector 4a being composed of an outer connector housing 4a2 and an inner connector housing 4a1. Connector 4b being composed of an outer connector housing 4b2 and an inner connector housing 4b1.

[0019] One side of each of the multiple bus bars 7 is disposed within the outer connector housing 4a2 and inner connector housing 4a1 of connector 4a, and the other side extends outside the inner connector housing 4a1 of connector 4a. Also, one side of each of the multiple bus bars 7 is disposed within the outer connector housing 4b2 and inner connector housing 4b1 of connector 4b, and the other side extends outside the inner connector housing 4b1 of connector 4b.

[0020] The control board 3 is held in the housing 2, and the other sides of the bus bars 7, 7 extending outward from the inner connector housing 4a1 of the connector 4a and the inner connector housing 4b1 of the connector 4b are inserted into through holes in the control board 3.

[0021] Because signal connectors 4 are susceptible to noise, they often have ferrite cores 5 attached. Packing 6 is inserted between the outer periphery 4c of connector 4 and the inner periphery 2a of housing 2 that faces outer periphery 4c of connector 4, sealing the gap between connector 4 and housing 2. Positioning packing 6 within the axial length of ferrite core 5 allows the length of busbar 7 to be minimized.

[0022] With the packing 6 attached to the connector 4, the connector 4 is fixed to the housing 2 with screws. After the connector 4 is fixed to the housing 2, the control board 3 is fixed to the housing 2 with screws, the bus bar 7 is inserted into the through hole of the control board 3, and the control board 3 and the bus bar 7 are electrically connected by soldering.

[0023] When the connector 4 is attached to the housing 2, a reaction force is unlikely to occur in the direction opposite to the direction in which the connector 4 is pushed into the housing 2, and the reaction force of the packing 6 occurs in a direction perpendicular to the direction in which the connector 4 is attached, so that the positional accuracy of the tip of the bus bar 7 soldered to the control board 3 is stable, resulting in good solderability and good accuracy in the amount of protrusion of the bus bar 7 from the control board 3.

[0024] 4 has an axial seal structure, but a face seal structure is also acceptable for the packing 6 that is designed to minimize the bus bar 7. By shortening the length of the bus bar 7, the volume of the conductive material is reduced, which has the advantages of lower material costs and lower electrical resistance.

[0025] Furthermore, the multiple bus bars 7 arranged in the connector 4 generally form a circuit in which current travels back and forth between adjacent bus bars 7, and the inductance is proportional to the length of the bus bars 7. Therefore, if the length of the bus bars 7 is shortened as in the present application, the inductance is reduced, and if noise is carried on the bus bars 7, the voltage fluctuation is reduced, resulting in a smaller error relative to the desired voltage.

[0026] Next, the structure of the connector 4 shown in Figure 5 will be described. Electrical device wiring structures 1 often use multiple connectors 4, and Figure 5 shows a structure in which two connectors 4a and 4b, which are originally separate components, are molded side-by-side. By arranging them side-by-side, the connector 4 becomes larger, and the shaft seal mounting portion becomes more susceptible to collapse due to resin shrinkage during molding. Therefore, a reinforcing rib 8 is provided in the center of the connector 4 to prevent the resin wall for mounting the packing 6 from collapsing.

[0027] As shown in Figure 5, when the ferrite core 5 is mounted inside the connector 4, the inner periphery of the packing 6 becomes longer, which causes more pronounced deformation, so the reinforcing rib 8 is an effective countermeasure. Also, the ferrite core 5 in Figure 5 is not circular, but has a straight portion 5a. In Figure 5, the ferrite core 5 is outsert, and a positioning structure 4d is attached to the connector 4, allowing positioning using the straight portion 5a of the ferrite core 5.

[0028] Also, insert molding is possible because the ferrite core 5 can be fixed during molding by applying the injection pressure during resin molding to the ferrite core 5 and pressing a mold against the straight portion 5a of the ferrite core 5. Furthermore, when two or more ferrite cores 5 are attached to the connector 4, there is the advantage that the cost of the mold for the ferrite core 5 can be reduced by making the ferrite cores 5 the same shape.

[0029] In addition, the connector opening that connects to the outside and the bus bar that is soldered extend straight, but it is easy to imagine a connector structure in which the bus bar is bent so that the direction of the soldered bus bar differs from the direction of the connector opening.

[0030] Second Embodiment Next, a second embodiment will be described with reference to Figures 6 and 7, with the same or corresponding components and parts being designated by the same reference numerals in each figure. Figure 6 is a cross-sectional view of the wiring structure of an electrical device according to the second embodiment, taken along line A-A in Figure 3. Figure 7 is an enlarged view of part B in Figure 6 of the wiring structure of an electrical device according to the second embodiment.

[0031] 7, the inner peripheral portion 2b of the housing 2 is tapered. By tapering the inner peripheral portion 2b of the housing 2, the connector 4 equipped with the packing 6 can be easily attached to the inner peripheral portion 2b of the housing 2, and the risk of the packing 6 being torn when sandwiched between the inner peripheral portion 2b of the housing 2 and the outer peripheral portion 4c of the connector 4 is reduced.

[0032] Embodiment 3. Next, embodiment 3 will be described with reference to Figures 8 to 10, with the same or equivalent members and parts in each figure being denoted by the same reference numerals. Figure 8 is a front view showing the wiring structure of an electrical device according to embodiment 3. Figure 9 is a cross-sectional view of the wiring structure of an electrical device according to embodiment 3 taken along line CC in Figure 8. Figure 10 is an enlarged view of part D in Figure 9 of the wiring structure of an electrical device according to embodiment 3.

[0033] In the third embodiment, a connector 4 is provided with an elastic engaging body 9, which has an arm 9a extending toward the outer periphery of the housing 2, with a claw-shaped engaging piece 9b, for example, provided at the tip of the arm 9a, and an engaging portion 2c, for example, a recess, with which the engaging piece 9b of the elastic engaging body 9 engages, provided on the outer periphery of the housing 2. When the connector 4 is attached to the housing 2, the arm 9a of the elastic engaging body 9 slides along the outer periphery of the housing 2 in a bent state, and when it reaches the engaging portion 2c, which is the recess of the housing 2, the engaging piece 9b of the elastic engaging body 9 engages with the engaging portion 2c, which is the recess of the housing 2, and is fixed.

[0034] 9 and 10 are described for the case where the engaging portion 2c of the housing 2 is a recess, but the same effect can be achieved by making the engaging portion 2c of the housing 2 a protrusion and providing an engaging hole at the tip of the engaging piece 9b of the elastic engaging body 9 provided on the connector 4 so that the engaging piece 9b formed by the engaging hole of the elastic engaging body 9 engages with the protrusion of the engaging portion 2c of the housing 2. Furthermore, as long as one or more elastic engaging bodies 9 are provided, they can exert a force to fix the housing 2, so there is no limit to the number of elastic engaging bodies 9.

[0035] Furthermore, the amount of compression of the packing 6 can be increased in parts other than the waterproof part of the packing 6 to fix the connector 4 to the housing 2. Of course, it is also possible to use an elastic body other than the packing 6 to provide a gap between the connector 4 and the housing 2, fill the gap with the elastic body, and fix the connector 4 to the housing 2.

[0036] Although various exemplary embodiments and examples are described in this application, the various features, aspects, and functions described in one or more embodiments are not limited to the application of a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless variations not illustrated are contemplated within the scope of the technology disclosed in this specification. For example, this includes cases where at least one component is modified, added, or omitted, or where at least one component is extracted and combined with components of another embodiment.

[0037] The present application is suitable for realizing a wiring structure for an electrical device that can stabilize the amount of bus bar protrusion from a control board.

[0038] 1 Wiring structure of electrical equipment, 2 Housing, 2a, 2b Inner peripheral portion, 3 Control board, 4, 4a, 4b Connector, 4a1, 4b1 Inner connector housing, 4a2, 4b2 Outer connector housing, 4c Outer peripheral portion, 4d Positioning structure, 5 Ferrite core, 5a Straight portion, 6 Packing, 7 Bus bar, 8 Reinforcing rib, 9 Elastic engagement body, 9a Arm portion, 9b Engagement piece

Claims

1. A wiring structure for an electrical device having a connector fixed to a housing and having a connector housing composed of an outer connector housing and an inner connector housing, a bus bar having one side disposed in the outer connector housing of the connector and the other side extending outside the inner connector housing of the connector, and a control board held in the housing and through which the other side of the bus bar is inserted, characterized in that the wiring structure for an electrical device is provided with a gasket inserted between the outer periphery of the connector and the inner periphery of the housing opposite the outer periphery of the connector to seal the gap between the connector and the housing.

2. The wiring structure for an electrical device according to claim 1, wherein the bus bar is surrounded by a ferrite core, and the packing is disposed within the axial length of the ferrite core.

3. The wiring structure for an electrical device according to claim 1 or 2, characterized in that the contact surface of the housing with the packing is formed in a tapered shape.

4. A wiring structure for an electrical device as described in claim 1 or claim 2, characterized in that an elastic engaging body is provided on the connector, and an engaging portion is provided on the outer periphery of the housing with which the engaging piece of the elastic engaging body engages.

5. The wiring structure for an electrical device according to claim 2, wherein the ferrite core has a straight portion.

6. The wiring structure for an electrical device according to claim 2 or 5, characterized in that a plurality of the ferrite cores are provided, and reinforcing ribs are provided between the ferrite cores.

7. The wiring structure for an electric device according to claim 6, wherein the plurality of ferrite cores are configured as ferrite cores of the same shape.

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