Charging inlet

Abstract

A charging inlet (1) comprises: a plurality of terminals (10) for power supply; an inlet housing (20) that holds the plurality of terminals (10) with tip end portions (11) thereof exposed to the outside; a rear case (40) that is connected to the inlet housing (20); a plurality of inner terminals (70) that are individually connected to base portions (12) of the plurality of terminals (10), inside the rear case (40), and are individually connected to the ends of a plurality of electric cables (100) introduced from the outside; and a filling portion (80). The rear case (40) includes: an accommodating portion (41) that accommodates, at least, the base portion (12) of each of the plurality of terminals (10) and the plurality of inner terminals (70); and fins (43e) that are exposed to the outside. The filling portion (80) is molded or configured from an insulating filler that fills the remaining part of the accommodating portion (41). The material of the rear case (40) is an electrically insulating thermally conductive resin obtained by filling a thermoplastic resin with a carbon-based or ceramic-based filler.

Description

Charging inlet

[0001] The present invention relates to a charging inlet.

[0002] Conventionally, there are charging inlets that are installed in vehicles such as electric vehicles or plug-in hybrid vehicles to supply power from outside the vehicle to the onboard battery. It is important for charging inlets to further suppress heat generation in order to accommodate higher output to shorten charging times. Patent Document 1 discloses technology related to a charging inlet that includes a cover structure with a cooling mechanism at the opening of a housing that houses part of a power supply terminal, which generates a particularly large amount of heat during charging.

[0003] US Patent Application Publication No. 2021 / 0021077

[0004] In the charging inlet disclosed in Patent Document 1, the cooling mechanism is provided in the cover structure that covers the opening of the housing, which makes the overall structure complex.

[0005] The present invention has been made in view of the problems inherent in the conventional technology, and an object of the present invention is to provide a charging inlet that has heat resistance and heat dissipation performance with a simple structure.

[0006] One aspect of the present invention is a charging inlet for connecting an external charging connector, comprising: a plurality of rod-shaped terminals for supplying power whose tips contact the external terminal of the charging connector; an inlet housing that holds the plurality of terminals with their tips exposed to the outside; a rear case connected to the inlet housing; a plurality of inner terminals that are individually connected to base portions of the plurality of terminals inside the rear case and individually connected to ends of a plurality of electric wires introduced from the outside; and a filling portion, wherein the rear case has a housing portion that houses at least the base portions of the plurality of terminals and the plurality of inner terminals, and fins exposed to the outside, and the filling portion is molded or formed from an insulating filler that fills the remaining portion of the housing portion, and the material of the rear case is an electrically insulating thermally conductive resin in which a carbon-based or ceramic-based filler is filled in a thermoplastic resin.

[0007] According to the present invention, it is possible to provide a charging inlet that has heat resistance and heat dissipation performance with a simple structure.

[0008] Fig. 1 is a perspective view of a charging inlet according to an embodiment. Fig. 2 is an exploded perspective view of a charging inlet according to an embodiment. Fig. 3 is a cross-sectional view of a charging inlet according to an embodiment. Fig. 4A is a perspective view that allows the front side of a rear case to be seen in an embodiment. Fig. 4B is a perspective view that allows the back side of a rear case to be seen in an embodiment. Fig. 4C is a perspective view that allows the back side of a rear case to be seen in an embodiment. Fig. 5 is a cross-sectional view of a charging inlet that illustrates a filling portion molding process.

[0009] A charging inlet according to one embodiment will be described in detail below with reference to the drawings. Note that the dimensional proportions in the drawings are exaggerated for the sake of convenience and may differ from the actual proportions.

[0010] Fig. 1 is a perspective view of a charging inlet 1 according to one embodiment. Fig. 2 is an exploded perspective view of the charging inlet 1. Note that in Fig. 2, a filling portion 80 is actually formed inside the rear case 40 by hardening a potting material after the charging inlet 1 is assembled, but for convenience, this filling portion 80 is depicted in an already hardened state. Fig. 3 is a cross-sectional view of the charging inlet 1 corresponding to section III-III in Fig. 1. The cross-section in Fig. 3 is an imaginary plane that includes the central axes of both of the two power supply terminals 10.

[0011] The charging inlet 1 is installed in a vehicle, such as an electric vehicle or a plug-in hybrid vehicle, and is a connector for supplying power to an on-board battery by appropriately connecting a charging connector (not shown) from outside the vehicle. The external charging connector is sometimes referred to as a "charging gun." The charging inlet 1 can be applied to various existing charging methods, but in this embodiment, it is illustrated as being compliant with the North American Charging Standard (NACS). Furthermore, for structures and the like not specifically mentioned or shown in the following description of the charging inlet 1, structures that comply with the NACS regulations can be applied.

[0012] As an example, the following description will assume that a charging connector is connected to the charging inlet 1, and define the direction in which the charging inlet 1 moves toward the charging connector as the X direction. In this case, the direction in which the charging connector moves toward the charging inlet 1 is opposite the X direction. The forward direction along the X direction may be referred to as "front," and the backward direction may be referred to as "rear." Furthermore, a YZ plane perpendicular to the X direction is assumed, and define the Y and Z directions perpendicular to each other. The Y direction is approximately horizontal. The Z direction is approximately opposite the vertical direction.

[0013] The charging inlet 1 comprises a plurality of terminals 10, an inlet housing 20, a terminal holding substrate 30, a rear case 40, a rear holder 50, a rear cover 60, a plurality of inner terminals 70, a plurality of bolts 71, a plug member 72, and a filling portion 80.

[0014] Each of the multiple terminals 10 is a rod-shaped male terminal made of metal. In particular, the terminals 10 here correspond to terminals for charging, i.e., power supply, that are connected to female terminals (not shown) (hereinafter referred to as "external terminals") provided on the charging connector when the charging connector is connected to the charging inlet 1. In this embodiment, the charging inlet 1 complies with the NACS and therefore has two terminals 10: a first terminal 10a that functions as a DC positive or AC positive terminal, and a second terminal 10b that functions as a DC negative or AC negative terminal.

[0015] Note that a charging inlet that complies with a general standard includes, in addition to a terminal for supplying power, a terminal for grounding, a terminal for transmitting a signal used to allow charging to begin, and a terminal for transmitting a signal used to confirm the connection of the charging connector. Although not shown, the charging inlet 1 that complies with the NACS also includes these three terminals.

[0016] Terminal 10 has a tip portion 11 and a base portion 12. When a charging connector is connected to charging inlet 1, tip portion 11 is directly connected to an external terminal. Base portion 12 is located rearward of tip portion 11 and connects one of a plurality of inner terminals 70. Base portion 12 has a bolt hole 12a formed in advance along the axial direction of terminal 10. Note that, in each terminal 10, a plug 11a manufactured separately in advance is provided on tip portion 11, and other portions may also be configured by combining a plurality of members.

[0017] The inlet housing 20 is made of synthetic resin, holds the terminals 10, and forms an exterior portion that is exposed to the outside when the charging connector is connected. The inlet housing 20 has a cylindrical portion 21, a protrusion 22, a flange portion 23, and a mounting frame portion 24.

[0018] Cylindrical portion 21 protects and positions tip portions 11 of the multiple terminals 10 in an internal space whose axial direction is the X direction. A charging port 21a is provided at the front end of cylindrical portion 21 as an opening into which the tip portion of a charging connector is fitted when starting charging. A rear end of cylindrical portion 21 is a rear wall portion 21b through which multiple terminal holding holes 21c pass and hold terminals such as terminals 10. In other words, for all terminals held in rear wall portion 21b, all tip portions, including tip portions 11 of each terminal 10, are positioned in the internal space of cylindrical portion 21 but are exposed to the outside through charging port 21a.

[0019] The protrusion 22 protrudes forward from the rear wall 21b inside the cylindrical portion 21, with its base end supported by the rear wall 21b. The protrusion 22 is provided to protect the terminals 10, etc., or to prevent erroneous insertion of the tip of the charging connector, and engages with a hole pre-formed in the charging connector when the tip of the charging connector is fitted into the cylindrical portion 21. When the tip of the charging connector is properly fitted into the cylindrical portion 21 in this manner, power is supplied to the vehicle battery from an external power source or the like, and the vehicle battery is charged.

[0020] The flange portion 23 supports the cylindrical portion 21 and the mounting frame portion 24. The specific shape of the flange portion 23 is determined according to the specifications of the vehicle in which the charging inlet 1 is installed. For example, bolt insertion holes 23a that penetrate in the X direction are formed at multiple locations on the flange portion 23. Bolts (not shown) are inserted into the bolt insertion holes 23a when the charging inlet 1 is attached to a predetermined location on the vehicle.

[0021] The mounting frame 24 is attached to the housing connection opening 42a of the rear case 40 when the inlet housing 20 is connected to the rear case 40. In this embodiment, the mounting frame 24 is a tubular portion with a circular opening cross section. One end of the mounting frame 24 is integrated with the flange 23 on the back side opposite to the front side where the tubular portion 21 is continuous. The other end of the mounting frame 24 is an open end that enters the interior of the housing connection opening 42a.

[0022] The terminal holding substrate 30 mounts and holds terminals for signal transmission separate from the terminals 10 for power supply. The terminal holding substrate 30 is disposed inside the mounting frame 24 of the inlet housing 20. The terminal holding substrate 30 has a circular planar shape that covers the bottom surface 23b on the flange portion 23 side when disposed on the mounting frame 24. The terminal holding substrate 30 has a plurality of terminal through-holes 31 and a plurality of pin terminals 32 used for signal transmission and the like. Each of the plurality of terminal through-holes 31 passes through a terminal 10. That is, in this embodiment, there are two terminal through-holes 31: one for passing the first terminal 10a and one for passing the second terminal 10b. The plurality of pin terminals 32 are a group of terminals that are electrically connected to the terminals for signal transmission and the like.

[0023] Fig. 4A is a perspective view showing the front side of the rear case 40. Fig. 4B and Fig. 4C are perspective views showing the back side of the rear case 40, each viewed from a different direction. Here, the front side of the rear case 40 refers to the side where the opening of the housing connection port 42a is open, i.e., the side to which the inlet housing 20 is connected. On the other hand, the back side of the rear case 40 is opposite the front side, in the opposite direction from the X direction, which corresponds to the direction in which the inlet housing 20 is connected to the rear case 40.

[0024] The rear case 40 is connected to the inlet housing 20 and has an accommodating portion 41 that accommodates at least the base portion 12 for each terminal 10 and a plurality of inner terminals 70. In this embodiment, the accommodating portion 41 accommodates at least the base portions 12 for two terminals 10 and the two inner terminals 70 corresponding to each terminal 10. The accommodating portion 41 will be described in detail below. The rear case 40 integrally includes a housing connecting portion 42, a wire connecting portion 43, a connection opening portion 44, and a connector portion 45.

[0025] The housing connecting portion 42 connects the mounting frame portion 24 of the inlet housing 20. The housing connecting portion 42 has a housing connecting opening portion 42a and a first bottom wall portion 42b.

[0026] The housing connection port 42a is a cylindrical portion into which the mounting frame 24 is fitted when connecting the housing connection portion 42. The axial direction of the housing connection port 42a is along the X direction, which is the connection direction to the inlet housing 20. The opening cross section of the housing connection port 42a is a circle that is preset to match the shape of the outer periphery of the mounting frame 24 so that the mounting frame 24 can be fitted. One end of the housing connection port 42a is an opening through which the mounting frame 24 is introduced when fitting the mounting frame 24. The other end of the housing connection port 42a is supported by the first bottom wall 42b.

[0027] The first bottom wall portion 42b is a flat portion perpendicular to the connecting direction. One of the main planes of the first bottom wall portion 42b faces the inner space of the housing connecting port portion 42a. The other main plane of the first bottom wall portion 42b faces the inner space of the tubular main body portion 43a of the wire connecting portion 43. The first bottom wall portion 42b also has terminal insertion holes 42c for inserting the base portions 12 of each terminal 10 into the tubular main body portion 43a when connecting the inlet housing 20 holding multiple terminals 10 to the housing connecting portion 42. The opening shape of the terminal insertion hole 42c is an elongated hole with a major axis set along the Y direction and a minor axis set along the Z direction so that two base portions 12 arranged side by side in the Y direction can be inserted into one hole.

[0028] The wire connection portion 43 forms a space portion that accommodates the ends of the plurality of wires 100 and connects the plurality of wires 100 to the base portions 12 of the corresponding terminals 10 via the inner terminals 70. In this embodiment, there are two wires 100. The wire connection portion 43 has a main body tubular portion 43a, a wire connection port portion 43b, and a second bottom wall portion 43c.

[0029] The main body tubular portion 43a constitutes the main body of the electric wire connection portion 43. The axial direction of the main body tubular portion 43a is along the opposite direction to the Y direction, which is the direction in which the electric wires 100 are introduced. The opening cross section of the main body tubular portion 43a is an elongated hole shape with the major axis set along the Z direction and the minor axis set along the X direction so that two electric wires 100 can be introduced in a parallel orientation in the Z direction. A portion of the outer surface of the main body tubular portion 43a is continuous with the housing connection port 42a. Another portion of the outer surface of the main body tubular portion 43a, which is located on the opposite side in the X direction from the portion continuous with the housing connection port 42a, is continuous with the connection work port 44.

[0030] The wire connection port 43b is one end of the main body tubular portion 43a and is an opening for introducing two electric wires 100 from the outside into the main body tubular portion 43a. In this embodiment, the opening cross section of the wire connection port 43b matches the opening cross section of the main body tubular portion 43a. In addition, the wire connection port 43b has a plurality of first locking protrusions 43d on its outer circumferential surface that engage with engaging pieces 53a provided on the rear holder 50 when the rear holder 50 is attached.

[0031] The second bottom wall portion 43c is the other end of the main body tubular portion 43a and is a wall portion that faces the opening of the electric wire connection port portion 43b in the Y direction.

[0032] The connection opening 44 is a cylindrical portion for performing the connection operation between the base portion 12 of the terminal 10 introduced through the terminal insertion hole 42c and the inner terminal 70 introduced through the wire connection opening 43b inside the cylindrical main body portion 43a of the wire connection portion 43. One end of the connection opening 44 is an opening for introducing the multiple bolts 71 and part of the tool used to fasten each bolt 71 during the connection operation. The other end of the connection opening 44 is supported on the outer surface of the cylindrical main body portion 43a, as described above. The opening of the connection opening 44 faces the opening of the terminal insertion hole 42c in the X direction via the cylindrical main body portion 43a. In other words, the axial direction of the connection opening 44 is aligned with the X direction. The cross section of the opening of the connection opening 44 is elongated, with the major axis set along the Y direction and the minor axis set along the Z direction. The connection opening 44 also has a plurality of second locking projections 44a on its outer circumferential surface that engage with the engagement pieces 62a provided on the rear cover 60 when the rear cover 60 is attached.

[0033] The connector portion 45 is a cylindrical portion that houses the multiple pin terminals 32 mounted on the terminal holding substrate 30 while exposing them to the outside. One end of the connector portion 45 is an opening for connecting an external connector. The other end of the connector portion 45 is supported by the first bottom wall portion 42b of the housing connecting portion 42. The hole portion 45a of the connector portion 45 opens from the first bottom wall portion 42b to the inside of the housing connecting portion 42. In other words, the axial direction of the connector portion 45 is along the X direction. The cross section of the opening of the connector portion 45 is rectangular with long sides set along the Y direction and short sides set along the Z direction.

[0034] As described above, the rear case 40 has an accommodating portion 41 that accommodates at least the base portions 12 of the two terminals 10 and the two inner terminals 70. The accommodating portion 41 is a portion of the rear case 40 that forms an internal space that is interconnected. Specifically, the accommodating portion 41 in this embodiment includes a portion that forms the internal space of the housing connecting portion 42, a portion that forms the internal space of the wire connecting portion 43, and a portion that forms the internal space of the connection opening 44, all of which are interconnected. In other words, the accommodating portion 41 is a portion of the rear case 40 that is sealed when the open ends of the housing connecting opening 42a, the wire connecting opening 43b, and the connection opening 44 are all closed. In other words, in this embodiment, the internal space that accommodates the base portions 12 of the two terminals 10 and the two inner terminals 70 corresponds to the internal space of the wire connecting portion 43, but the accommodating portion 41 is not limited to the portion that forms the internal space of the wire connecting portion 43.

[0035] The rear case 40 also has fins 43e exposed to the outside. The fins 43e are integrally molded with the rear case 40. In the present embodiment, the fins 43e are provided on the wire connection portion 43, as an example. Here, the rear holder 50 is attached to the wire connection port 43b of the wire connection portion 43. Therefore, the fins 43e are provided on the entire outer surface of each of the main body tubular portion 43a and the second bottom wall portion 43c, which are portions of the wire connection portion 43 excluding the wire connection port 43b. For example, the main body tubular portion 43a is provided with a plurality of fins 43e that are arranged parallel to each other in the Y direction and spaced apart at a regular interval. The second bottom wall portion 43c is provided with a plurality of fins 43e that are arranged parallel to each other in the X direction and spaced apart at a regular interval. Each fin 43e is a plate-shaped portion that protrudes to the same height from the outer surface of the main body tubular portion 43a or the second bottom wall portion 43c. However, since the main body cylindrical portion 43a includes a cylindrical portion near the electric wire connection port portion 43b, some of the fins 43e may be annular as a whole.

[0036] The specific shape or arrangement of the fins 43e in this embodiment is merely an example, and may be changed as appropriate, for example, in accordance with a change in the shape of the rear case 40. Furthermore, although the present embodiment illustrates the case where the fins 43e are provided on the electric wire connection portion 43, the fins 43e may also be provided on the connection opening 44, for example.

[0037] The rear case 40 is made of an electrically insulating, heat-conductive resin in which a carbon-based or ceramic-based filler is filled into the thermoplastic resin. In this embodiment, the thermoplastic resin is a polyester-based resin. Specifically, the polyester-based resin is polybutylene terephthalate (PBT). However, other thermoplastic resins, such as polyarylene-based resins, polyamide-based resins, or polyolefin-based resins, may also be used.

[0038] The thermal conductivity of simple thermoplastic resin is extremely low, even compared to that of aluminum, for example. Therefore, to increase the thermal conductivity, a highly thermally conductive carbon-based or ceramic-based filler is filled into the thermoplastic resin. This makes the resin used as the material for the rear case 40 an insulating type, so-called high thermal conductivity resin, with a thermal conductivity of, for example, 1.0 [W / (m·k)] or higher. The specific material of the carbon-based or ceramic-based filler is not particularly limited, as long as it can provide an appropriate thermal conductivity.

[0039] The rear holder 50 is made of synthetic resin and is attached to the electric wire connection port 43b of the rear case 40 so as to close the opening of the electric wire connection port 43b with two electric wires 100 inserted through the electric wire connection port 43b. The rear holder 50 integrally includes a plurality of support tube portions 51, a top plate portion 52, and an annular frame portion 53.

[0040] The plurality of support cylinder portions 51 are provided for each electric wire 100, and support the electric wire 100 by passing the electric wire 100 through the support cylinder portions 51 and coming into close contact with the outer peripheral surface of the electric wire 100. In this embodiment, there are two support cylinder portions 51.

[0041] The top plate portion 52 is a flat plate portion that is perpendicular to the opposite direction to the Y direction, which is the attachment direction of the rear holder 50 to the electric wire connection port 43b. The top plate portion 52 supports the two support tube portions 51 on one main flat surface side, with each opening open on the other main flat surface side. The top plate portion 52 covers the opening of the electric wire connection port 43b when the rear holder 50 is attached to the electric wire connection port 43b. Therefore, the planar shape of the top plate portion 52 is set in advance to match the outer cross section of the electric wire connection port 43b. Furthermore, the top plate portion 52 supports each support tube portion 51 so that their central axes are aligned along the Y direction and are parallel to each other in the Z direction.

[0042] When the rear holder 50 is attached to the wire connection port 43 b, the annular frame 53 introduces the tip of the wire connection port 43 b into the interior and faces closely to the outer circumferential surface of the wire connection port 43 b. The annular frame 53 is continuous with the edge of the main plane of the top plate 52 on the side opposite to the side on which the two support cylinders 51 are supported. A portion of the annular frame 53 is elastically deformable and has a plurality of engaging pieces 53 a formed with engaging holes that each engage with one of the plurality of first locking protrusions 43 d when the rear holder 50 is attached to the wire connection port 43 b.

[0043] The rear cover 60 is made of synthetic resin and is attached to the connection access port 44 so as to cover the opening of the connection access port 44 of the rear case 40. The rear cover 60 integrally includes a top plate portion 61 and an annular frame portion 62.

[0044] Top plate 61 is a flat plate that is perpendicular to the opposite direction to the Z direction, which is the attachment direction of rear cover 60 to connection opening 44. The planar shape of top plate 61 is set in advance to match the external cross section of connection opening 44.

[0045] The annular frame 62 is continuous with the edge of the top plate 61, and when the rear cover 60 is attached to the connection opening 44, the tip of the connection opening 44 is introduced into the annular frame 62, and the annular frame 62 faces closely to the outer circumferential surface of the connection opening 44. A portion of the annular frame 62 is elastically deformable and has a plurality of engaging pieces 62a formed with engaging holes that each engage with one of the plurality of second locking projections 44a when the rear cover 60 is attached to the connection opening 44.

[0046] The inner terminals 70 are terminal fittings manufactured by machining a sheet metal material having a certain thickness. The inner terminals 70 are individually connected to the base portions 12 of the terminals 10 and also individually connected to the ends of the electric wires 100 introduced from the outside. In this embodiment, there are two inner terminals 70: a first inner terminal 70a connected to the first terminal 10a and a second inner terminal 70b connected to the second terminal 10b.

[0047] Here, a plurality of electric wires 100 corresponding to the respective power supply terminals 10 are connected to the charging inlet 1. That is, in this embodiment, two electric wires 100 are connected to the charging inlet 1: a first electric wire 100a corresponding to the first terminal 10a, and a second electric wire 100b corresponding to the second terminal 10b. Each electric wire 100 has a core wire 101 which is a conductor and a sheath 102 which is an insulator that covers the core wire 101. The end of the core wire 101 exposed at one end of each electric wire 100 is joined to one of the two inner terminals 70. The other end of each electric wire 100 is pre-connected to an object inside the vehicle, such as an on-board battery.

[0048] In this embodiment, the two electric wires 100 are introduced in the direction opposite to the Y direction into the rear case 40, which houses the base portions 12 of the terminals 10, each oriented with its axial direction aligned with the X direction. In this case, the first inner terminal 70a and the second inner terminal 70b may each have the following structure or shape.

[0049] First, the second inner terminal 70b integrally includes a second connecting portion 70f and a second joint portion 70h. The second connecting portion 70f is a linear flat plate having a second through-hole 70g at its tip. When the second inner terminal 70b is housed in the main body tubular portion 43a of the rear case 40, the second connecting portion 70f contacts the base portion 12 of the second terminal 10b while its main plane is maintained parallel to the YZ plane. At this time, the second through-hole 70g is positioned approximately coaxially with the bolt hole 12a of the second terminal 10b. The second joint portion 70h is continuous with the second connecting portion 70f in the Y direction and joins the end of the core wire 101 of the second electric wire 100b. In this embodiment, the second joint portion 70h is a crimping portion that crimps the end of the core wire 101 of the second electric wire 100b. That is, in the Z direction, the height position of the central axis of the end portion of the second wire 100b is approximately the same as the height position of the central axis of each of the bolt holes 12a of the first terminal 10a and the second terminal 10b.

[0050] On the other hand, the first inner terminal 70a integrally includes a first connecting portion 70c and a first joint portion 70e. The first electric wire 100a, which is to be connected to the first inner terminal 70a, is introduced into the main body tubular portion 43a of the rear case 40 in parallel with the second electric wire 100b. Therefore, the height positions of the first electric wire 100a and the second electric wire 100b in the Z direction are different from each other. On the other hand, the first connecting portion 70c is a flat plate portion having a first through hole 70d at its tip. However, since the height positions of the bolt holes 12a of the first terminal 10a and the second terminal 10b in the Z direction are substantially the same, the height positions of the first through hole 70d and the second through hole 70g are also substantially the same. Therefore, the planar shape of the first connecting portion 70c is L-shaped so as to avoid the second connecting portion 70f, as shown in FIG. 2 . When the first inner terminal 70a is housed in the main body tubular portion 43a of the rear case 40, the first connecting portion 70c contacts the base portion 12 of the first terminal 10a while maintaining its principal plane parallel to the YZ plane. At this time, the first through-hole 70d is positioned approximately coaxially with the bolt hole 12a of the first terminal 10a. The first joint portion 70e is continuous with the first connecting portion 70c in the Y direction and joins an end of the core wire 101 of the first electric wire 100a. In this embodiment, the first joint portion 70e, like the second joint portion 70h, is a crimping portion that crimps an end of the core wire 101 of the first electric wire 100a. When the first inner terminal 70a and the second inner terminal 70b are housed in the main body tubular portion 43a, the first joint portion 70e and the second joint portion 70h are positioned approximately the same in the Y direction.

[0051] The plurality of bolts 71 are fastening members used to fasten the base portion 12 of the terminal 10 to the inner terminal 70. In this embodiment, there are two bolts 71: one that is fastened to the bolt hole 12a of the first terminal 10a after the bolt shank passes through the first through hole 70d, and one that is fastened to the bolt hole 12a of the second terminal 10b after the bolt shank passes through the second through hole 70g.

[0052] The plug member 72 is, for example, a rubber plug, and seals the gap between the electric wire connection port 43b and the plurality of electric wires 100. The plug member 72 has two electric wire through holes 72a through which two electric wires 100 are individually passed. The plug member 72 is tightly held inside the electric wire connection port 43b in a state in which the electric wires 100 pass through each of the electric wire through holes 72a while being in close contact with each other.

[0053] In this embodiment, the filling portion 80 is formed by filling the remaining portion of the accommodating portion 41 with a potting material, which is an insulating filler. Here, the remaining portion of the accommodating portion 41 refers to the space excluding the elements disposed inside the accommodating portion 41, such as the base portion 12 of each terminal 10 and each inner terminal 70. In other words, after the filling portion 80 is formed, there is almost no space in the accommodating portion 41.

[0054] In this embodiment, the potting material used to form the filling portion 80 is a synthetic resin that is liquid before hardening and hardens at room temperature. For example, a silicone-based resin, which has excellent heat resistance, electrical insulation, and flexibility, is used. However, the specific material of the synthetic resin is not limited to these examples.

[0055] Next, a manufacturing process of the charging inlet 1 will be described assuming that the filling portion 80 is molded from a potting material.

[0056] The manufacturing process of the charging inlet 1 includes a process of assembling the charging inlet 1 and a process of molding a filling portion that is performed after the assembly process. Note that the manufacturing process may be performed by a worker, or may be performed in a factory where some or all of the manufacturing process is automated.

[0057] In the process of assembling the charging inlet 1, first, an inlet housing 20 is prepared, which preliminarily holds a plurality of terminals, including the power supply terminal 10, and a terminal holding substrate 30. Additionally, a first electric wire 100a having a first inner terminal 70a attached to its end, and a second electric wire 100b having a second inner terminal 70b attached to its end are prepared.

[0058] Next, the mounting frame portion 24 of the inlet housing 20 is fitted into the housing connecting portion 42 of the rear case 40, thereby connecting the inlet housing 20 to the rear case 40. At this time, at least a portion of the base portion 12 for each terminal 10 is introduced into the interior of the main body tubular portion 43a through the terminal insertion hole 42c.

[0059] Furthermore, the tip end of the first electric wire 100a, to which the first inner terminal 70a is attached, and the tip end of the second electric wire 100b, to which the second inner terminal 70b is attached, are introduced into the interior of the main body tubular portion 43a through the electric wire connection port 43b. Then, after the gap between the electric wire connection port 43b and the two electric wires 100 is sealed with the plug member 72, the rear holder 50 is attached to the electric wire connection port 43b. At this time, the first through hole 70d provided in the first inner terminal 70a is positioned approximately coaxially with the bolt hole 12a of the first terminal 10a, and the first connection portion 70c is adjacent to the base portion 12 of the first terminal 10a. Similarly, the second through hole 70g provided in the second inner terminal 70b is positioned so as to be approximately coaxial with the bolt hole 12a of the second terminal 10b, while the second connection portion 70f is close to the base portion 12 of the second terminal 10b.

[0060] Next, each bolt 71 is introduced into the interior of the tubular main body portion 43a through the connection opening 44 of the rear case 40. Subsequently, part of a tool used to tighten each bolt 71 is introduced into the interior of the tubular main body portion 43a through the connection opening 44. Then, by tightening one of the bolts 71, the first connection portion 70c of the first inner terminal 70a is connected to the base portion 12 of the first terminal 10a. Similarly, by tightening the other bolt 71, the second connection portion 70f of the second inner terminal 70b is connected to the base portion 12 of the second terminal 10b. This completes the assembly process of the charging inlet 1. However, at this stage, the rear cover 60 has not yet been attached to the connection opening 44 of the rear case 40.

[0061] FIG. 5 is a cross-sectional view of the charging inlet 1 illustrating the filling portion molding process, which is drawn to correspond to FIG.

[0062] In the filling portion molding process, first, the charging inlet 1 after the assembly process is maintained in an orientation in which the X direction is aligned with the vertical direction. Next, as indicated by the hollow arrow in FIG. 5 , the potting material before hardening is introduced into the accommodation portion 41 through the connection opening 44. The potting material is introduced until the remaining portion of the accommodation portion 41 is filled. At this time, the mounting frame 24 of the inlet housing 20 is fitted into the housing connection opening 42a of the rear case 40, preventing leakage of the potting material through the housing connection opening 42a. Furthermore, the plug member 72 and the rear holder 50 are attached to the electric wire connection opening 43b of the rear case 40, preventing leakage of the potting material through the electric wire connection opening 43b.

[0063] Next, the rear cover 60 is attached to the connection opening 44. As a result, the remaining portion of the housing section 41 in the rear case 40 is sealed in a state where it is filled with the potting material before hardening.

[0064] In this embodiment, the synthetic resin used for the potting material hardens at room temperature, so the potting material hardens when left to stand, forming the filling portion 80. This completes the filling portion molding process for the charging inlet 1, and ultimately completes the manufacturing process for the charging inlet 1.

[0065] For example, when charging inlets 1 are manufactured in a factory with automated manufacturing processes, it is conceivable that the manufacturing process will proceed with multiple charging inlets 1 placed on a conveyor. In this case, the charging inlet 1 with the rear cover 60 attached to the connection opening 44 is left on the conveyor for approximately 30 minutes, allowing the filling portion 80 to form naturally. In other words, as long as approximately 30 minutes have passed since the rear cover 60 was attached to the connection opening 44, the charging inlet 1 removed from the conveyor is in a completed state, i.e., ready to be shipped as a product.

[0066] Next, the effects of the charging inlet 1 will be described.

[0067] First, the charging inlet 1, which connects to an external charging connector, includes multiple rod-shaped terminals 10 for supplying power, whose tip ends 11 contact the external terminals of the charging connector, and an inlet housing 20 that holds the multiple terminals 10 with their tip ends 11 exposed to the outside. The charging inlet 1 also includes a rear case 40 connected to the inlet housing 20. The charging inlet 1 also includes multiple inner terminals 70 that are individually connected to the base portions 12 of the multiple terminals 10 and individually connected to the ends of multiple electric wires 100 introduced from the outside within the rear case 40, and a filling portion 80. The rear case 40 has a housing portion 41 that houses at least the base portions 12 of the multiple terminals 10 and the multiple inner terminals 70, and fins 43e exposed to the outside. The filling portion 80 is molded or formed from an insulating filler that fills the remaining portion of the housing portion 41. The rear case 40 is made of an electrically insulating, thermally conductive resin formed by filling a thermoplastic resin with a carbon-based or ceramic-based filler.

[0068] In the above example, the plurality of terminals 10 correspond to two terminals 10, namely, the first terminal 10a and the second terminal 10b. In the above example, the plurality of electric wires 100 correspond to two electric wires 100, namely, the first electric wire 100a and the second electric wire 100b. In the above example, the plurality of inner terminals 70 correspond to two inner terminals 70, namely, the first inner terminal 70a and the second inner terminal 70b.

[0069] In the charging inlet 1, the remaining portion of the accommodation portion 41 that accommodates each terminal 10, which generates a particularly large amount of heat during charging, and the inner terminals 70 connected to each terminal 10, is filled with a filling portion 80 that is molded or configured from an insulating filler. That is, the filling portion 80 is in direct contact with at least a portion of the terminal 10 and the entire inner terminal 70. Therefore, in the accommodation portion 41, the filling portion 80 can directly absorb and store heat from each terminal 10 and each inner terminal 70 during charging. Therefore, the charging inlet 1 can achieve heat resistance that complies with pre-defined charging standards with a simple structure.

[0070] Furthermore, because the remaining portion of the accommodation portion 41 is filled with the filling portion 80, there is little or no spatial area in the remaining portion where air simply exists. Generally, air in an enclosed space has an insulating effect and can inhibit heat transfer. In other words, with the charging inlet 1, the spatial area where air exists in the remaining portion of the accommodation portion 41 can be minimized, thereby improving the heat transfer performance from the terminal 10 and the inner terminal 70 during charging.

[0071] Furthermore, in the charging inlet 1, the rear case 40 that directly contacts the filling portion 80 is made of a highly thermally conductive resin, and a portion of the rear case 40 is provided with fins 43e that are exposed to the outside. This allows the rear case 40 to absorb heat stored in the filling portion 80 and release the heat to the outside through the fins 43e. Therefore, the charging inlet 1 can achieve more suitable heat dissipation performance with a simple structure.

[0072] As described above, according to this embodiment, it is possible to provide the charging inlet 1 that has heat resistance and heat dissipation performance with a simple structure.

[0073] In addition, in the charging inlet 1, the thermoplastic resin may be a polyester-based resin.

[0074] According to the charging inlet 1, the resin constituting the highly thermally conductive resin that can be used as the material for the rear case 40 can satisfy the requirements for heat resistance and the like.

[0075] In addition, in charging inlet 1, the polyester resin may be polybutylene terephthalate.

[0076] According to the charging inlet 1, since polybutylene terephthalate is a general-purpose so-called engineering plastic, the manufacturing cost of the charging inlet 1 can be reduced, for example.

[0077] Furthermore, in the charging inlet 1, the rear case 40 may have a wire connection portion 43 that forms a space for connecting the wire 100 to the base portion 12 of the terminal 10 via the inner terminal 70. The fin 43e may be provided on the wire connection portion 43.

[0078] According to the charging inlet 1, the fins 43e are provided in a position close to a part of the rear case 40 where the amount of heat generated is particularly large during charging, and therefore, higher heat dissipation performance can be achieved.

[0079] In addition, in the charging inlet 1, the filler material may be a potting material.

[0080] In this case, the filling portion 80 is formed from the potting material filled in the remaining portion of the accommodation portion 41. The potting material is initially liquid and has the property of hardening when heated or left at room temperature. Therefore, when providing the filling portion 80 in the remaining portion of the accommodation portion 41, the potting material can be spread to every corner of the remaining portion. Therefore, with this charging inlet 1, it is possible to further improve the heat transfer performance from the terminal 10 and the inner terminal 70 during charging.

[0081] In addition, in the charging inlet 1, the potting material may be a synthetic resin that hardens at room temperature.

[0082] With this charging inlet 1, the base portion 12 and the inner terminal 70 for each terminal 10 are connected to each other, and the filling portion 80 can be formed naturally by simply introducing the potting material before it hardens into the storage portion 41.

[0083] Furthermore, in the charging inlet 1, the synthetic resin may be a silicone-based resin.

[0084] According to the charging inlet 1, the filling section 80 is more suitable for storing heat, and therefore higher heat resistance can be obtained.

[0085] Furthermore, in the charging inlet 1, the filler may be a heat dissipation sheet.

[0086] In this case, the filling portion 80 is composed of a heat dissipation sheet filled in the remaining portion of the accommodating portion 41. The heat dissipation sheet is a sheet-like member manufactured by blending boron nitride or the like with a synthetic resin such as silicone resin, and has both high insulating and high thermal conductivity properties. When providing the filling portion 80 in the remaining portion of the accommodating portion 41, instead of the filling portion molding process described above, which corresponds to the case where the filling portion 80 is formed using a potting material, a filling portion construction process is performed in which a heat dissipation sheet is inserted into the remaining portion. In the filling portion construction process, for example, a heat dissipation sheet prepared in advance in a long, thin strip shape may be wrapped around the terminal 10 or the inner terminal 70, or a heat dissipation sheet prepared in strips may be packed into the remaining portion. In this case, compared to when the filling material is a potting material, a large amount of air may be present in the remaining portion of the accommodating portion 41, but the remaining portion can be largely filled with the heat dissipation sheet. Therefore, with the charging inlet 1, it is possible to improve the heat transfer performance from the terminal 10 and the inner terminal 70 during charging with a simpler structure or manufacturing process than when the filler is a potting material.

[0087] In the above description, a potting material made of a synthetic resin such as silicone resin is used as an example of a potting material for forming the filling portion 80. However, the potting material for forming the filling portion 80 may be a synthetic resin such as silicone resin further mixed with a metal powder such as aluminum alloy powder. Such a potting material has superior thermal conductivity compared to potting materials that do not contain metal powder. Therefore, a filling portion 80 formed with such a potting material is more suitable for heat storage than one formed with a potting material that does not contain metal powder, and as a result, higher heat resistance can be achieved.

[0088] In addition, in the charging inlet 1, as an example where the direction toward the external charging connector, i.e., the protruding direction of the multiple terminals 10, is defined as the X direction, the routing direction of the multiple electric wires 100 from the rear case 40 is along the Y direction, which is a roughly horizontal direction. However, the embodiment of the charging inlet 1 is not limited to this. For example, even if the posture of the inlet housing 20 of the charging inlet 1 is the same as the above example, the routing direction of the multiple electric wires 100 from the rear case 40 may be along the direction opposite to the Z direction, which is a roughly vertical direction.

[0089] The entire contents of Japanese Patent Application No. 2024-097495 (filing date: June 17, 2024) are incorporated herein by reference.

[0090] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims.

[0091] REFERENCE SIGNS LIST 1 Charging inlet 10 Terminal 10a First terminal 10b Second terminal 11 Tip portion 12 Base portion 20 Inlet housing 40 Rear case 41 Storage portion 43 Electric wire connection portion 43e Fin 70 Inner terminal 70a First inner terminal 70b Second inner terminal 80 Filling portion 100 Electric wire 100a First electric wire 100b Second electric wire

Claims

1. A charging inlet for connecting an external charging connector, comprising: a plurality of rod-shaped terminals for supplying power whose tips contact the external terminals of the charging connector; an inlet housing that holds the plurality of terminals with the tips exposed to the outside; a rear case connected to the inlet housing; a plurality of inner terminals that are individually connected to base parts of the plurality of terminals inside the rear case and individually connected to ends of a plurality of electric wires introduced from the outside; and a filling section, wherein the rear case has a housing section that houses at least the base parts of the plurality of terminals and the plurality of inner terminals, and fins exposed to the outside, the filling section is molded or made of an insulating filler that fills the remaining part of the housing section, and the material of the rear case is an electrically insulating, thermally conductive resin in which a carbon-based or ceramic-based filler is filled in a thermoplastic resin.

2. The charging inlet according to claim 1, wherein the thermoplastic resin is a polyester-based resin.

3. The charging inlet according to claim 2, wherein the polyester resin is polybutylene terephthalate.

4. A charging inlet according to any one of claims 1 to 3, wherein the rear case has a wire connection section that forms a space for connecting the wire to the base section of the terminal via the inner terminal, and the fin is provided on the wire connection section.

5. The charging inlet according to any one of claims 1 to 4, wherein the filling material is a potting material.

6. The charging inlet according to claim 5, wherein the potting material is a synthetic resin that hardens at room temperature.

7. The charging inlet according to claim 6, wherein the synthetic resin is a silicone-based resin.

8. The charging inlet according to any one of claims 1 to 4, wherein the filler is a heat dissipation sheet.

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