Connection structure between electric wire and circuit board, and temperature measuring unit

Abstract

To provide a connection structure between an electric wire and a circuit board, which can be reduced in height.SOLUTION: A connection structure 1 between an electric wire 20 and a circuit board 10 includes: the electric wire 20 having a core wire 21 and an insulating sheath 22 covering a circumference of the core wire 21; the circuit board 10 including an electric wire land to which the core wire 21 is to be connected by soldering; and a hard substrate 30 overlaid onto the circuit board 10 in a thickness direction of the circuit board 10. The hard substrate 30 includes an accommodating part 33 penetrating in the thickness direction and being open in a direction orthogonal to the thickness direction. The accommodating unit 33 includes a core wire accommodating part 35 accommodating the core wire 21, and is overlaid onto the electric wire land in the thickness direction.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a connection structure between an electric wire and a circuit board, and a temperature measurement unit.

Background Art

[0002] Conventionally, a temperature sensor described in Japanese Patent Application Laid-Open No. 2012-37384 (Patent Document 1 below) is known. This temperature sensor includes a thermistor that measures temperature, and a molded resin part that integrally forms the thermistor and a bracket. The bracket is provided with a thermistor temporary holding part that temporarily holds the thermistor and an electric wire temporary holding part that temporarily holds an electric wire led out to the outside of the molded resin part.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above configuration, since the molded resin part is formed so as to cover the thermistor, the connection part between the thermistor and the electric wire, and the bracket that temporarily holds the thermistor and the electric wire, it is likely to be enlarged. Therefore, the wiring space for the temperature sensor is narrow, and when it is necessary to reduce the height of the temperature sensor, it may be difficult to adopt the above configuration.

[0005] Unlike the above configuration, it is conceivable to configure a temperature sensor by electrically connecting an electric wire to a circuit board on which a thermistor is mounted. Enabling reduction in height of such a connection structure between an electric wire and a circuit board is an important issue not only for temperature sensors but also for configurations in various applications.

Means for Solving the Problems

[0006] The connection structure between an electric wire and a circuit board according to the present disclosure comprises an electric wire having a core wire and an insulating coating covering the outer circumference of the core wire; a circuit board having wire lands to which the core wire is connected by soldering; and a rigid substrate arranged superimposed on the circuit board in the thickness direction of the circuit board, wherein the rigid substrate has a housing portion that penetrates in the thickness direction and opens in a direction perpendicular to the thickness direction, the housing portion has a core wire housing portion in which the core wire is housed, and is arranged superimposed on the wire lands in the thickness direction. [Effects of the Invention]

[0007] According to this disclosure, it is possible to provide a connection structure between electric wires and circuit boards that allows for a lower profile design. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a perspective view of a temperature measuring unit according to Embodiment 1. [Figure 2] Figure 2 is an exploded perspective view of the temperature measuring unit. [Figure 3] Figure 3 is a plan view of the temperature measuring unit with some of the power lines omitted. [Figure 4] Figure 4 is a cross-sectional view of AA in Figure 3. [Figure 5] Figure 5 is a perspective view of a temperature measuring unit equipped with heat-shrink tubing and a protective member. [Figure 6] Figure 6 is a perspective view of the battery module. [Figure 7] Figure 7 is a plan view of the battery module. [Figure 8] Figure 8 is a cross-sectional view of BB in Figure 7. [Figure 9] Figure 9 is an enlarged perspective view of the bracket. [Figure 10] Figure 10 is a perspective view showing a fuse unit according to Embodiment 2. [Modes for carrying out the invention]

[0009] [Description of Embodiments of the Present Disclosure] First, embodiments of the present disclosure will be listed and described.

[0010] (1) The connection structure between the electric wire and the circuit board of the present disclosure includes an electric wire having a core wire and an insulating coating covering the outer periphery of the core wire, a circuit board provided with an electric wire land to which the core wire is connected by soldering, and a rigid substrate disposed to overlap the circuit board in the thickness direction of the circuit board. The rigid substrate has a housing portion that penetrates in the thickness direction and opens in a direction orthogonal to the thickness direction. The housing portion has a core wire housing portion in which the core wire is housed, and is disposed to overlap the electric wire land in the thickness direction.

[0011] According to such a configuration, by filling the inside of the housing portion with solder for connecting the electric wire and the circuit board, it is easy to control the shape and the dimensions in the thickness direction of the solder. Therefore, the connection structure between the electric wire and the circuit board can be made lower-profile.

[0012] (2) In the connection structure between the electric wire and the circuit board described in (1), it is preferable that the housing portion has a plating portion formed on at least a part of the inner wall of the housing portion.

[0013] According to such a configuration, it becomes easier to fill the inside of the housing portion with solder. Further, by connecting the solder and the plating portion, the connection strength of the solder can be increased.

[0014] (3) In the connection structure between the electric wire and the circuit board described in (2), it is preferable that the dimension of the plating portion in the thickness direction is formed with a negative tolerance with respect to the dimension of the rigid substrate in the thickness direction.

[0015] According to such a configuration, it is possible to suppress the plating portion from being formed outside the housing portion. Therefore, it is possible to suppress the solder from leaking out of the housing portion.

[0016] (4) In the connection structure between the electric wire and the circuit board according to any one of (1) to (3), it is preferable that the accommodating portion has an opening end that opens in a direction orthogonal to the thickness direction, and an insulating coating accommodating portion that is arranged on the opening end side continuously with the core wire accommodating portion and accommodates the insulating coating.

[0017] According to such a configuration, the insulating coating can be accommodated in the accommodating portion. Therefore, the movement of the portion of the electric wire accommodated in the insulating coating accommodating portion with respect to the rigid substrate can be restricted. Thus, it is possible to suppress the generation of stress at the connection portion between the core wire and the wire land due to the stress or vibration applied to the electric wire. In addition, it is possible to suppress damage to the core wire in the portion not covered with solder due to the stress or vibration applied to the electric wire concentrating on the core wire.

[0018] (5) In the connection structure between the electric wire and the circuit board according to (4), it is preferable that the insulating coating accommodating portion has a rounded arc portion in an end region including the opening end, and is formed wider as it approaches the opening end.

[0019] According to such a configuration, it is possible to suppress damage to the insulating coating by contacting the end portion on the opening end side of the accommodating portion.

[0020] (6) In the connection structure between the electric wire and the circuit board according to any one of (1) to (5), it is preferable that the rigid substrate has a resist on the surface arranged on the opposite side to the circuit board in the thickness direction.

[0021] According to such a configuration, it is possible to suppress the adhesion of solder to the surface of the rigid substrate.

[0022] (7) The temperature measurement unit of the present disclosure includes the connection structure between the electric wire and the circuit board according to any one of (1) to (6), and a thermistor mounted on the circuit board.

[0023] According to such a configuration, the temperature measurement unit can be made low-profile.

[0024] [Details of the embodiments of this disclosure] Embodiments of the present disclosure are described below. The present disclosure is not limited to these examples, but is indicated by the claims, and all modifications within the meaning and scope equivalent to the claims are intended.

[0025] <Embodiment 1> Embodiment 1 of this disclosure will be described with reference to Figures 1 to 9. In the following description, the direction indicated by arrow Z is considered upward, the direction indicated by arrow X is considered forward, and the direction indicated by arrow Y is considered left. Note that for multiple identical components, reference numerals may be assigned to only some of the components, while the reference numerals for other components may be omitted.

[0026] As shown in Figure 1, this embodiment describes an example in which a connection structure 1 (hereinafter referred to as connection structure 1) between the electric wire 20 and the circuit board 10 is applied to the temperature measuring unit 2. The temperature measuring unit 2 comprises a circuit board 10 on which a thermistor P1 is mounted, an electric wire 20, and a rigid substrate 30.

[0027] [Circuit board] The circuit board 10 in this embodiment is a flexible substrate. As shown in Figure 2, the circuit board 10 has an overall elongated shape in the front-to-back direction. The circuit board 10 comprises a main body portion 11 that is substantially rectangular in plan view, and two first extensions 12 that extend rearward from the rear end of the main body portion 11. The two first extensions 12 are arranged side by side in the left-to-right direction. The circuit board 10 is constructed by forming conductive paths 13 on the surface of a flexible insulating sheet using printed wiring technology.

[0028] [Electric Wire Land] The circuit board 10 is provided with two conductive paths 13 extending in the front-to-back direction. The two conductive paths 13 are arranged side by side in the left-to-right direction. A wire land 13A is formed at one end (rear end) of the conductive path 13. An element land 13B is formed at the other end (front end) of the conductive path 13. The two wire lands 13A are each positioned near the rear end of the first extension 12. A wire 20 is connected to each of the two wire lands 13A by soldering. A recess 12A is provided at a position behind the wire lands 13A of the first extension 12, recessed forward from the rear end of the first extension 12.

[0029] A thermistor P1 is positioned in the center of the left-right direction, near the front end of the main body 11. The thermistor P1 is connected to two element lands 13B provided in the two conductive paths 13. Each of the two element lands 13B is connected to the electrodes of thermistor P1 by soldering.

[0030] [Electric wire] The temperature measuring unit 2 of this embodiment is connected to two wires 20. The wires 20 are connected to a device (not shown) that measures the resistance value of the thermistor P1 via a connector (not shown). The wires 20 comprise a core wire 21 and an insulating sheath 22 covering the outer circumference of the core wire 21. At the ends of the wires 20, the insulating sheath 22 is removed, exposing the core wire 21. As shown in Figure 4, the core wire 21 is connected to the wire land 13A of the circuit board 10 by soldering.

[0031] [Hard substrate] The rigid substrate 30 is formed, for example, by impregnating a glass fiber cloth with epoxy resin and curing it. As shown in Figure 2, the rigid substrate 30 has a roughly gate shape in plan view. The rigid substrate 30 comprises a base portion 31 that is roughly rectangular in plan view, and two second extension portions 32 that extend rearward from the rear end of the base portion 31. The two second extension portions 32 are arranged side by side in the left-right direction. As shown in Figure 1, the rigid substrate 30 is arranged superimposed on the circuit board 10 in the thickness direction (vertical direction) of the circuit board 10. For example, the rigid substrate 30 is superimposed on the circuit board 10 such that the thickness direction of the rigid substrate 30 is aligned with the thickness direction of the circuit board 10. The lower surface of the rigid substrate 30 is attached to the upper surface of the circuit board 10 with an adhesive or the like. Each second extension portion 32 is positioned to overlap with each first extension portion 12 in the vertical direction. The base portion 31 is positioned so as to overlap with the rear end of the main body portion 11 in the vertical direction.

[0032] [Housing section, open end] As shown in Figure 2, each second extension 32 has a housing portion 33 that penetrates vertically and opens to the rear (an example of a direction perpendicular to the thickness direction). The housing portion 33 extends in the front-rear direction. The housing portion 33 has, for example, an open end 34 that opens to the rear, a core wire housing portion 35 in which the core wire 21 is housed, and an insulating coating housing portion 36 in which the insulating coating 22 is housed.

[0033] [Core wire housing section, insulation housing section] As shown in Figure 3, the core wire housing section 35 is located on the side opposite to the open end 34 (front side) of the housing section 33. For example, the core wire housing section 35 has a length of about three-quarters of the housing section 33 in the front-to-back direction. The insulating coating housing section 36 is located on the side of the open end 34 (rear side), continuous with the core wire housing section 35. For example, the insulating coating housing section 36 has a length of about one-quarter of the housing section 33 in the front-to-back direction.

[0034] The width (horizontal dimension) of the core wire housing section 35 is set to be slightly larger than the thickness of the core wire 21. The width of the insulation coating housing section 36 is set to be slightly larger than the thickness of the insulation coating 22 (electric wire 20). Also, the width of the insulation coating housing section 36 is greater than the width of the core wire housing section 35. The rear end of the core wire housing section 35 and the front end of the insulation coating housing section 36 are smoothly connected by an inclined section 37 that slopes so that the width of the housing section 33 widens towards the rear.

[0035] [R section] The insulating coating housing portion 36 has a rounded radius portion 38 in the end region including the open end 34. The radius portion 38 smoothly connects the left and right inner walls of the insulating coating housing portion 36 to the rear end surface of the second extension portion 32. Due to the provision of the radius portion 38, the insulating coating housing portion 36 is formed to be wider as it approaches the open end 34.

[0036] The accommodating section 33 is arranged overlapping the wire land 13A in the vertical direction. In a plan view, at least a portion of the wire land 13A is located inside the accommodating section 33. In this embodiment, the wire land 13A is arranged overlapping the entire core wire accommodating section 35 and the front portion of the inclined section 37. As shown in Figure 4, in this embodiment, the width of the wire land 13A is set to be greater than the width of the core wire accommodating section 35. Both ends of the wire land 13A in the width direction are positioned opposite the lower surfaces of the rigid substrates 30 located on both sides of the core wire accommodating section 35.

[0037] The core wire 21 housed in the core wire housing section 35 is placed on the wire land 13A. The solder S1 connecting the core wire 21 and the wire land 13A is filled into the core wire housing section 35. This prevents the solder S1 from protruding beyond the hard substrate 30 in the thickness direction of the circuit board 10. Therefore, the housing section 33 makes it easier to control the shape and height of the solder S1. This makes it easier to reduce the height of the connection structure 1.

[0038] [Plating part] In this embodiment, the housing section 33 has a plated portion 39 formed on at least a part of the inner wall of the housing section 33. The plated portion 39 is made of, for example, copper, tin, nickel, etc. The provision of the plated portion 39 improves the wettability of the solder S1 to the inner wall of the housing section 33, making it easier to fill the housing section 33 with solder S1. In addition, since the plated portion 39 is connected to the solder S1 together with the wire land 13A and the core wire 21, the connection strength of the solder S1 connecting the core wire 21 and the wire land 13A can be increased. Therefore, it is preferable that the area on which the plated portion 39 is provided includes at least a part of the inner wall of the core wire housing section 35. In this embodiment, the plated portion 39 is provided on substantially the entire inner wall of the housing section 33.

[0039] In this embodiment, the vertical dimension of the plated portion 39 is formed with a negative tolerance relative to the vertical dimension of the hard substrate 30. This prevents the plated portion 39 from forming on the upper surface of the hard substrate 30 if the manufacturing tolerance of the plated portion 39 becomes large. Therefore, it is possible to prevent solder S1 from adhering to the upper surface of the hard substrate 30. Furthermore, it is possible to prevent solder S1 from rising above the upper surface of the hard substrate 30. Note that the vertical dimension of the plated portion 39 being formed with a negative tolerance relative to the vertical dimension of the hard substrate 30 means that the vertical dimension of the plated portion 39 is less than or equal to the vertical dimension of the hard substrate 30. Also, the upper end of the plated portion 39 may be located below the upper surface of the hard substrate 30.

[0040] [Resist] The rigid substrate 30 has a resist 40 on the surface (top surface) that is located on the side opposite to the circuit board 10 in the thickness direction. The resist 40 is made of an insulating material and repels molten solder S1. Therefore, it is possible to suppress the adhesion of solder S1 to the top surface of the rigid substrate 30.

[0041] As shown in Figure 5, the temperature measuring unit 2 may include a heat-shrinkable tube 41 to protect the connection structure 1 and a protective member 42 to protect the thermistor P1. The heat-shrinkable tube 41 covers the first extension 12, the second extension 32, and the end of the electric wire 20 from the outside. The protective member 42 is a plate-like shape that is roughly rectangular in plan view. A housing hole 43 is provided in the center of the protective member 42, penetrating the protective member 42 in the vertical direction. The protective member 42 is attached to the upper surface of the front end of the main body 11 with an adhesive or the like. The thermistor P1 is placed inside the housing hole 43. The protective member 42 is made of an elastic material such as sponge.

[0042] [Regarding the manufacturing process of temperature measuring units] The configuration of the temperature measuring unit 2 in this embodiment is as described above, and now an example of the manufacturing process for the temperature measuring unit 2 will be explained below.

[0043] A circuit board 10 is formed using printed circuit board technology, and a thermistor P1 is mounted on the circuit board 10. A plated portion 39 and a resist 40 are formed on the hard substrate 30.

[0044] Next, the upper surface of the circuit board 10 and the lower surface of the rigid substrate 30 are attached together using an adhesive or the like. The first extension portion 12 and the second extension portion 32 are arranged to overlap in the vertical direction.

[0045] A core wire 21 of a predetermined length is exposed at the end of the electric wire 20. The electric wire 20 with the core wire 21 exposed is inserted into the housing portion 33 of the rigid substrate 30. The core wire 21 is placed in the core wire housing portion 35, and the insulating sheath 22 is placed in the insulating sheath housing portion 36. The lower part of the tip of the insulating sheath 22 is housed inside a recess 12A provided in the circuit board 10.

[0046] Solder S1 is filled into the housing section 33. More specifically, the solder S1 is filled into a groove-shaped space formed by the left and right inner walls of the core wire housing section 35 and the upper surface of the wire land 13A. Since a plated portion 39 is provided on the inner wall of the housing section 33, the solder S1 spreads easily within the housing section 33. Furthermore, the plated portion 39 is formed with a negative tolerance to the vertical dimension of the inner wall of the housing section 33, and a resist 40 is provided on the upper surface of the hard substrate 30, making it difficult for the solder S1 to move from inside the housing section 33 to the upper surface of the hard substrate 30. Therefore, the solder S1 can be kept inside the housing section 33, and the shape and height dimensions of the solder S1 can be stabilized.

[0047] [Regarding the usage of the temperature measurement unit] The temperature measuring unit 2 of this embodiment is attached to an object to be measured and used to measure the temperature of that object. The following describes an example of the configuration of a battery module 3 that measures the temperature of the energy storage element 4 using the temperature measuring unit 2, with reference to Figures 6 to 9. This battery module 3 can be mounted in vehicles such as electric vehicles or hybrid vehicles.

[0048] As shown in Figure 6, the battery module 3 comprises a temperature measuring unit 2, a group of energy storage elements 4S in which multiple energy storage elements 4 are stacked, and a bracket 50 attached to the upper surface of the group of energy storage elements 4S. The energy storage elements 4 are flat rectangular parallelepipeds. Energy storage elements (not shown) are housed inside the energy storage elements 4. The energy storage elements 4 have positive and negative electrode terminals 4A and 4B on their upper surfaces.

[0049] The bracket 50 is made of an insulating synthetic resin. As shown in Figures 6 and 7, the bracket 50 is plate-shaped and has an electrode insertion hole 51 and a temperature measuring unit mounting section 52. The electrode terminals 4A and 4B of the energy storage element 4 are inserted through the electrode insertion hole 51. The temperature measuring unit 2 is mounted in the temperature measuring unit mounting section 52. As shown in Figure 9, the temperature measuring unit mounting section 52 has a cable routing recess 53 that is groove-shaped and extends in the front-rear direction, a temperature measuring opening 54, and a pressing wall 55. The cable routing recess 53 comprises a bottom wall 53A and a pair of side walls 53B that extend upward from both side edges of the bottom wall 53A. The pair of side walls 53B extend upward relative to the upper surface of the bracket 50. The temperature measuring opening 54 is located at the front end of the temperature measuring unit mounting section 52 and penetrates the bottom wall 53A in the vertical direction. The pair of side walls 53B form the wall portion of the temperature-measuring opening 54. At the front portion of the temperature-measuring opening 54, the upper ends of the pair of side walls 53B are connected by a pressing wall 55. The pressing wall 55 covers the front portion of the temperature-measuring opening 54 from above.

[0050] As shown in Figure 8, the rear half of the temperature measuring unit 2, specifically the rear end of the main body 11, the first extension 12, the rigid substrate 30, the electric wire 20, and the heat shrink tubing 41 are arranged in the cable routing recess 53. The front end of the temperature measuring unit 2, specifically the front end of the main body 11, the thermistor P1, and the protective member 42 are positioned between the upper surface of the energy storage element 4 and the pressing wall 55. The protective member 42, which is made of an elastic material, is pressed downward by the pressing wall 55. That is, the distance between the upper surface of the energy storage element 4 and the lower surface of the pressing wall 55 is set to be slightly smaller than the thickness of the protective member 42 in its natural state. As a result, the front end of the main body 11 on which the thermistor P1 is mounted is pressed against the upper surface of the energy storage element 4, which is the object to be measured.

[0051] The front end of the main body 11 rests on the upper surface of the energy storage element 4, and the rear end of the main body 11 rests on the bottom wall 53A of the cable routing recess 53. Therefore, the front end of the main body 11 is located lower than the rear end of the main body 11. However, in this embodiment, since the circuit board 10 is flexible, the middle portion of the main body 11 takes on a curved shape, which can absorb vertical displacement of the front and rear ends of the main body 11.

[0052] Since the temperature measuring unit 2 is located inside the vehicle, it is expected to be subjected to vibrations and stresses that pull on the electric wires 20. In this embodiment, a plated portion 39 is provided on the inner wall of the housing portion 33, which improves the connection strength of the solder S1. Therefore, it is easier to ensure the electrical connection between the electric wires 20 and the circuit board 10 even when subjected to vibrations inside the vehicle.

[0053] In this embodiment, since the housing portion 33 has an insulating coating housing portion 36, stress on the electric wire 20 is less likely to concentrate on the core wire 21. Therefore, it is possible to suppress the breakage of the portion of the core wire 21 that is not covered by the solder S1 and insulating coating 22. In addition, in this embodiment, the insulating coating housing portion 36 has a rounded portion 38, so that no sharp corners are formed at the end of the housing portion 33 on the open end 34 side. Therefore, it is possible to suppress the insulating coating 22 from coming into contact with and being damaged at the end of the housing portion 33 on the open end 34 side in a vibrating environment.

[0054] [Effects of Embodiment 1] According to Embodiment 1, the following actions and effects are achieved. The connection structure 1 between the electric wire 20 and the circuit board 10 according to Embodiment 1 comprises an electric wire 20 having a core wire 21 and an insulating coating 22 covering the outer circumference of the core wire 21; a circuit board 10 having an electric wire land 13A to which the core wire 21 is connected by soldering; and a rigid substrate 30 arranged superimposed on the circuit board 10 in the thickness direction (vertical direction) of the circuit board 10. The rigid substrate 30 has a housing portion 33 that penetrates in the thickness direction and opens in a direction perpendicular to the thickness direction, and the housing portion 33 has a core wire housing portion 35 in which the core wire 21 is housed, and is arranged superimposed on the electric wire land 13A in the thickness direction.

[0055] With this configuration, the shape and thickness of the solder S1 connecting the electric wire 20 and the circuit board 10 can be easily controlled by filling the housing section 33 with solder S1. Therefore, it is possible to suppress the increase in size of the connection structure 1 between the electric wire 20 and the circuit board 10 in the thickness direction of the circuit board 10 due to the solder S1. Consequently, the connection structure 1 between the electric wire 20 and the circuit board 10 can be made lower in profile.

[0056] In Embodiment 1, the housing portion 33 has a plated portion 39 formed on at least a part of the inner wall of the housing portion 33.

[0057] This configuration makes it easier to fill the inside of the housing section 33 with solder S1. In addition, the connection between solder S1 and the plated section 39 increases the connection strength of solder S1.

[0058] In Embodiment 1, the thickness dimension of the plated portion 39 is formed with a negative tolerance relative to the thickness dimension of the hard substrate 30.

[0059] This configuration makes it possible to prevent the plating portion 39 from forming outside the housing portion 33. Therefore, it is possible to prevent the solder S1 from leaking outside the housing portion 33.

[0060] In Embodiment 1, the housing portion 33 has an open end 34 that opens in a direction perpendicular to the thickness direction (rearward), and an insulating coating housing portion 36 that is arranged on the open end 34 side, continuous with the core wire housing portion 35, and houses the insulating coating 22.

[0061] With this configuration, the insulating coating 22 can be housed in the housing section 33. Therefore, the movement of the portion of the electric wire 20 housed in the insulating coating housing section 36 relative to the rigid substrate 30 can be restricted. Consequently, stress on the connection between the core wire 21 and the electric wire land 13A due to stress and vibration on the electric wire 20 can be suppressed. Furthermore, damage to the core wire 21 in the portion not covered by solder S1 can be suppressed by concentrating the stress and vibration on the electric wire 20 on the core wire 21.

[0062] In Embodiment 1, the insulating coating housing portion 36 has a rounded radius portion 38 in the end region including the open end 34, and is formed to become wider as it approaches the open end 34.

[0063] This configuration prevents the insulating coating 22 from coming into contact with and damaging the end of the housing portion 33 on the open end 34 side.

[0064] In Embodiment 1, the rigid substrate 30 has a resist 40 on the surface (top surface) that is located on the side opposite to the circuit board 10 in the thickness direction.

[0065] This configuration makes it possible to suppress the adhesion of solder S1 to the surface of the hard substrate 30.

[0066] The temperature measuring unit 2 according to Embodiment 1 comprises a connection structure 1 between the electric wire 20 and the circuit board 10, and a thermistor P1 mounted on the circuit board 10.

[0067] This configuration allows for a lower profile for the temperature measuring unit 2.

[0068] <Embodiment 2> Embodiment 2 of this disclosure will be described with reference to Figure 10. In this embodiment, an example will be described in which a connection structure 101 (hereinafter referred to as connection structure 101) between an electric wire 20 and a circuit board 110 is applied to a fuse unit 105. Unlike Embodiment 1, in this embodiment, the fuse unit 105 is provided with one connection structure 101. That is, in the fuse unit 105, one electric wire 20 and one circuit board 110 are connected. In the following description, components configured in the same way as in Embodiment 1 will be denoted by the same reference numerals as in Embodiment 1, and detailed descriptions may be omitted.

[0069] The fuse unit 105 comprises a circuit board 110 on which a chip fuse P2 is mounted, a rigid substrate 130, and electric wires 20. The circuit board 110 is a flexible substrate. The circuit board 110 comprises a main body portion 111 which is substantially rectangular in plan view, a first extension portion 112 which extends rearward from the rear end of the main body portion 111, and an expandable portion 114 provided on the front side of the main body portion 111. The expandable portion 114 is formed in a crank shape with notches. The expandable portion 114 is displaceable by a predetermined length in the vertical, horizontal, and front-to-back directions relative to the main body portion 111.

[0070] The circuit board 110 is provided with two conductive paths 113. Of the two conductive paths 113, the conductive path 113 located in the rear portion of the circuit board 110 comprises a wire land (not shown) located at its rear end and an element land 13B located at its front end. In Figure 10, the wire land is hidden by the hard substrate 130 and the wire 20, but its configuration is the same as the wire land 13A in Embodiment 1. Of the two conductive paths 113, the conductive path 113 located in the front portion of the circuit board 110 comprises an element land 13B located at its rear end and a busbar-side land 113C located at its front end.

[0071] The busbar-side land 113C is located on the expandable portion 114. The busbar-side land 113C is connected to the rear end of the metal piece 106 by soldering. The front end of the metal piece 106 is connected to the busbar 107 by welding or the like. In other words, the busbar-side land 113C is electrically connected to the busbar 107 via the metal piece 106. The busbar 107 is connected to the electrode terminals of an energy storage element (not shown). The energy storage elements are stacked to form an energy storage element group, and are arranged in the vehicle in the same manner as in Embodiment 1.

[0072] A chip fuse P2 is located in the center of the main body 111. The chip fuse P2 is connected to two element lands 13B provided on two conductive paths 113. Each of the two element lands 13B is connected to the electrodes of the chip fuse P2 by soldering.

[0073] The rigid substrate 130 comprises a base portion 131 and a second extension portion 132 extending rearward from the base portion 131. Except for the difference in the number of second extension portions 132, the rigid substrate 130 is configured similarly to the rigid substrate 30 of Embodiment 1. The electric wire 20 is arranged in the housing portion 33 and connected to the electric wire land by solder (not shown) that fills the housing portion 33.

[0074] The fuse unit 105 in this embodiment is part of a so-called voltage detection line. The wire 20 is connected to an ECU (Electronic Control Unit) or the like via a connector (not shown). The ECU is a well-known configuration equipped with a microcomputer, elements, etc., and has functions for detecting the voltage, current, temperature, etc. of each energy storage element, and for controlling the charging and discharging of each energy storage element.

[0075] The configuration of this embodiment is as described above. The effects and advantages of this embodiment are the same as those of Embodiment 1, so their explanation will be omitted.

[0076] <Other Embodiments> (1) In the above embodiment 1, a portion of the core wire housing portion 35 and the inclined portion 37 of the housing portion 33 were arranged to overlap with the wire land 13A, but the invention is not limited to this, and it is sufficient if at least a portion of the housing portion is arranged to overlap with the wire land. (2) In the above embodiments 1 and 2, the circuit boards 10 and 110 were flexible substrates, but the invention is not limited to these, and the circuit board may be a rigid substrate. (3) In Embodiment 1, the circuit board 10 was equipped with a thermistor P1, and in Embodiment 2, the circuit board 110 was equipped with a chip fuse P2, but the circuit board is not limited to these, and may be equipped with electronic components other than these. Also, the circuit board may not be equipped with electronic components at all. (4) In Embodiment 1, two wires 20 were connected to one circuit board 10, and in Embodiment 2, one wire 20 was connected to one circuit board 110. However, the invention is not limited to these two configurations, and the number of wires connected to a single circuit board can be arbitrarily selected. (5) In Embodiment 1 above, a temperature measuring unit 2 was exemplified, and in Embodiment 2 above, a fuse unit 105 was exemplified, but the connection structure between the electric wire and the circuit board of this disclosure may be applied to a configuration other than these. (6) The housing section 33 does not have to have an insulating housing section 36. For example, the housing section 33 may not have an insulating housing section 36, but may have an open end 34 and a core wire housing section 35 in which the core wire 21 is housed. [Explanation of Symbols]

[0077] 1,101: Wires, circuit boards, and connection structures 2: Temperature measuring unit 3: Battery module 4: Energy storage element 4A,4B: Electrode terminal 4S: Energy storage element group 10,110: Circuit board 11,111: Main body 12,112: 1st extension part 12A: Recess 13,113: Conductive path 13A: Electric Wire Land 13B: Motoko Land 20: Electric wire 21: Core wire 22: Insulation coating 30,130: Rigid substrate 31,131: Base 32,132: 2nd extension part 33: Detention Unit 34: Open end 35: Core wire housing 36: Insulated coating housing 37: Inclined part 38: R section 39: Plating part 40: Resist 41: Heat shrink tubing 42: Protective component 43: Containment port 50: Bracket 51: Electrode insertion hole 52: Temperature measurement unit installation section 53: Routing recess 53A: Bottom wall 53B: Side wall 54: Temperature measurement opening 55: Pressure wall 105: Fuse Unit 106: Small metal pieces 107: Bus Bar 113C: Busbar side land 114: Telescopic part P1: Thermistor P2: Chip fuse S1: Handa

Claims

1. A wire having a core wire and an insulating coating covering the outer circumference of the core wire, A circuit board having wire pads to which the aforementioned core wires are connected by soldering, The circuit board comprises a rigid substrate that is superimposed on the circuit board in the thickness direction, When the direction perpendicular to the thickness direction is defined as the front-to-back direction, and the direction perpendicular to both the thickness direction and the front-to-back direction is defined as the width direction, The rigid substrate has a housing portion that penetrates in the thickness direction and opens to the rear, The aforementioned housing portion is arranged to overlap with the wire land in the thickness direction, The aforementioned housing structure for connecting an electric wire to a circuit board comprises a core wire housing portion in which the core wire is housed, an open end that opens to the rear, an insulating coating housing portion that is arranged to the rear of the core wire housing portion and houses the insulating coating, and an inclined portion that connects the rear end of the core wire housing portion and the front end of the insulating coating housing portion, and is inclined such that the width dimension of the housing portion increases towards the rear.

2. The connection structure between an electric wire and a circuit board according to claim 1, wherein the housing portion has a plated portion formed on at least a part of the inner wall of the housing portion.

3. The connection structure between an electric wire and a circuit board according to claim 2, wherein the dimension of the plated portion in the thickness direction is formed with a negative tolerance relative to the dimension of the hard substrate in the thickness direction.

4. The connection structure between an electric wire and a circuit board according to claim 1, wherein the insulating coating housing portion has a rounded radius portion in the end region including the open end, and is formed to become wider as it approaches the open end.

5. The connection structure between an electric wire and a circuit board according to any one of claims 1 to 3, wherein the rigid substrate has a resist on a surface that is located on the opposite side of the circuit board in the thickness direction.

6. A connection structure between an electric wire and a circuit board according to any one of claims 1 to 3, A temperature measuring unit comprising a thermistor mounted on the aforementioned circuit board.

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