Pre-inserted connector, wire harness with connector, and method for manufacturing pre-inserted connector.

Abstract

To provide a terminal-inserted connector and the like capable of securing a cut-off performance with excellent maintainability.SOLUTION: A terminal is connected to a coated conductor wire 11 at a crimping part 17. Hardening resin 19 is applied to one part in a peripheral direction including at least a top face side of the crimping part 17 of a resultant electric wire 1 with a terminal. Before the hardening resin 19 is hardened, the terminal is inserted in a terminal insertion part 23 of a connector housing 25, to which a mold release agent 27 is applied in advance. Then, the hardening resin 19 is hardened. This can obtain a terminal-inserted connector, in which at least one part of the crimping part 17 is in close contact with an inner face of the terminal insertion part 23 via the hardening resin 19.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a terminal-inserted connector with a terminal of a terminal-equipped electric wire used for electric wiring bodies such as moving bodies like vehicles and aircrafts, industrial robots, OA equipment, and home appliances, a wire harness with a connector, and a method for manufacturing the same.

Background Art

[0002] Conventionally, in fields such as automobiles, OA equipment, and home appliances, electric wires made of copper-based materials with excellent electrical conductivity have been used as power lines and signal lines. In particular, in the automobile field, the performance and functionality of vehicles are rapidly improving, and the number of various electric devices and control devices mounted on vehicles is increasing. Accordingly, the number of terminal-equipped electric wires used tends to increase accordingly.

[0003] Such terminal-equipped electric wires are sometimes used by being inserted into connectors. A plurality of terminal insertion portions are formed in the connector, and the terminals of the terminal-equipped electric wires are inserted into these terminal insertion portions and fixed there. By doing this, a plurality of terminal-equipped electric wires can be connected at one time.

[0004] On the other hand, with environmental issues attracting attention, weight reduction of automobiles is required. Therefore, the weight increase accompanying the increase in the usage amount of wire harnesses becomes a problem. For this reason, lightweight aluminum electric wires have attracted attention instead of conventionally used copper wires.

[0005] Here, when connecting such electric wires to each other or at connection parts of equipment and the like, connection terminals are used. However, even for a terminal-equipped electric wire using an aluminum electric wire, copper with excellent electrical properties may be used for the terminal part for the sake of reliability of the connection part and the like. In such a case, the aluminum electric wire and the copper terminal are bonded and used.

[0006] However, when dissimilar metals are brought into contact, there is a risk of so-called electrolytic corrosion due to the difference in standard electrode potential. In particular, the difference in standard electrode potential between aluminum and copper is large, so corrosion of the electrically less noble aluminum side progresses due to the effects of water splashing or condensation at the contact point. As a result, the connection between the wire and terminal at the connection point becomes unstable, which can lead to increased contact resistance, increased electrical resistance due to a decrease in wire diameter, and even wire breakage, potentially causing malfunction or failure of electrical components.

[0007] Therefore, as a countermeasure, Patent Document 1 proposes a method to prevent corrosion of the metal at the terminal connection by applying a modified silicone resin to the terminal connection and hardening the resin, thereby preventing the electrolyte from entering the terminal connection.

[0008] Furthermore, Patent Document 2 proposes a method of injecting a dark-curing ultraviolet-curing resin, which is a sealing material, into the gap between the outer surface of an electric wire inserted into the terminal housing chamber of the housing and the inner surface of the terminal housing chamber. In Patent Document 2, by simply irradiating the ultraviolet-curing resin exposed to the outside at the electric wire insertion opening of the terminal housing chamber with ultraviolet light, the ultraviolet-curing resin in parts of the terminal housing chamber that cannot be irradiated with ultraviolet light also hardens, preventing water from entering the terminal housing chamber of the housing. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Japanese Patent Publication No. 2013-25931 [Patent Document 2] Japanese Patent Publication No. 2014-207106 [Overview of the Initiative] [Problems that the invention aims to solve]

[0010] As mentioned above, in order to prevent corrosion of insulated wires with terminals using aluminum wires, it is important to protect the exposed aluminum portion of the terminal connection from the electrolyte. In Patent Documents 1 and 2, defects in the resin coating on the connection between the aluminum wire and the copper terminal are unacceptable.

[0011] However, in the case of Patent Document 1, a method is used to adhere modified silicone resin to the exposed aluminum portion by dropping, coating, or extruding. However, modified silicone resin tends to have a high viscosity among resin materials, making it difficult to spread the resin to all the necessary areas. In particular, it is difficult to cover the exposed aluminum portion of the side opening of the open barrel terminal.

[0012] Furthermore, when applying resin using a dispenser, for example, it is necessary to move the nozzle in a complex manner to ensure that the resin is applied precisely to the required areas, but this has the drawback of extending the application time. This effect is particularly pronounced as the diameter of the wire increases. Although a method has been proposed to reduce the viscosity of the resin by heating it to allow it to spread to the desired areas, this is expensive in terms of equipment costs, and depending on the curing method, the curing speed may accelerate too much, potentially causing defects or adverse effects on the equipment. In addition, with curable resins that harden over time, storage becomes complicated, as it is necessary to avoid contact with objects until the resin is touch-dry to prevent peeling in the uncured state immediately after application.

[0013] Furthermore, in the case of Patent Document 2, a low-viscosity resin must be used to avoid voids during injection, and high-viscosity resins and adhesives cannot be used. Also, since the sealing material is injected after inserting the insulated wire with terminals into the terminal housing chamber, it is not possible to visually confirm whether the exposed portion of the aluminum wire is properly covered. For this reason, corrosion is unavoidable, for example, if a small gap occurs in the opening of the terminal housing chamber or if there are areas where the aluminum wire is not adequately covered.

[0014] Furthermore, because this method involves injecting the sealing material into the terminal housing chamber, it takes more time compared to coating methods such as those described in Patent Document 1. In addition, a curing process is required after injection, resulting in a very long manufacturing time. Moreover, because dark-curable UV-curing resins have a fast reaction rate, careful handling is required, and their handling properties are poor. Furthermore, in the case of dark-curable UV-curing resins that use long-life radical species, the curing time becomes longer, reducing productivity.

[0015] Furthermore, if a low-viscosity resin is used to ensure that the sealing material is properly distributed within the terminal housing, the resin will adhere to the entire axial circumference of the terminal-equipped wire. However, this will firmly fix the terminal-equipped wire to the housing, making it impossible to remove the insulated wire from the housing. As a result, maintainability becomes extremely low from the perspective of repairs and hardware updates, which have been attracting attention recently.

[0016] This invention has been made in view of the above problems, and aims to provide a terminal-inserted connector and the like that offers excellent maintainability and ensures high watertightness. [Means for solving the problem]

[0017] To achieve the aforementioned objective, the first invention is a terminal-inserted connector in which at least one terminal is inserted into a terminal insertion portion of a connector housing, wherein the terminal has a terminal body and a crimping portion, the terminal is connected to a covered conductor at the crimping portion, is covered with a curable resin so as to cover at least the upper surface of the crimping portion, and the crimping portion and the curable resin are bonded together by the curing of at least a portion of the curable resin, and the shear adhesive force between the curable resin and the inner surface of the terminal insertion portion is smaller than the shear adhesive force between the curable resin and the crimping portion.

[0018] The curable resin may be cured at the contact point with the crimping portion, but not cured at the contact point with the inner surface of the terminal insertion portion.

[0019] The entire curable resin is cured, and a release agent may be applied between the inner surface of the terminal insertion portion and the curable resin.

[0020] The entire curable resin is cured, and a semi-solid material may be disposed between the inner surface of the terminal insertion portion and the curable resin.

[0021] It is preferable that the shear adhesive strength of the curable resin to the crimping portion measured in accordance with JIS K6850 (1999) is 0.2 MPa or more, and the shear adhesive strength of the curable resin to the inner surface of the terminal insertion portion measured in accordance with JIS K6850 (1999) is 0.001 MPa or less.

[0022] According to the first aspect of the invention, the terminal insertion portion of the connector housing into which the terminal of the electric wire with terminal is inserted is filled with resin so as to cover at least the connection portion between the terminal and the electric wire, so that the resin can suppress the intrusion of water into the terminal connection portion.

[0023] At this time, since at least a part of the curable resin is cured to bond the crimping portion and the curable resin together, intrusion of water into the crimping portion can be prevented. Further, since the shear adhesive strength between the curable resin and the inner surface of the terminal insertion portion is small, the terminal and the connector housing are not completely bonded to each other, and the terminal can be pulled out from the connector housing. Therefore, replacement of terminals and the like can be performed in maintenance and other operations. Even in this case, since the terminal and the connector housing are in close contact with each other via the curable resin, water stopping performance can be maintained.

[0024] For example, by curing the curable resin at the contact portion with the crimping portion and leaving it in an uncured state at the contact portion with the inner surface of the terminal insertion portion, the shear adhesive strength between the curable resin and the inner surface of the terminal insertion portion can be reduced.

[0025] Further, even when the entire curable resin is cured, applying a release agent between the inner surface of the terminal insertion portion and the curable resin can reduce the shear adhesive force between the curable resin and the inner surface of the terminal insertion portion.

[0026] Further, even when the entire curable resin is cured, disposing a non-curable semi-solid between the inner surface of the terminal insertion portion and the curable resin can also reduce the shear adhesive force between the curable resin and the inner surface of the terminal insertion portion.

[0027] In this case, if the shear adhesive force of the curable resin to the crimping portion measured in accordance with JIS K6850(1999) is 0.2 MPa or more, sufficient water stopping performance can be ensured. On the other hand, if the shear adhesive force of the curable resin to the inner surface of the terminal insertion portion measured in accordance with JIS K6850(1999) is 0.001 MPa or less, the terminal can be easily pulled out from the connector housing.

[0028] The second invention is a wire harness with a connector, which uses the terminal-inserted connector according to the first invention, wherein the connector housing has a plurality of the terminal insertion portions, and the plurality of terminals connected to the coated conductive wires are inserted into the terminal insertion portions.

[0029] According to the second invention, it is possible to obtain a wire harness with a connector that includes a plurality of terminal-attached electric wires, has high water stopping performance and excellent maintainability.

[0030] The third invention is a method for manufacturing a terminal-inserted connector, comprising the steps of: connecting a coated conductive wire via the crimping portion to a terminal having a terminal body and the crimping portion; applying a release agent or a curing inhibitor to the inner surface of the terminal insertion portion of a connector housing; applying a curable resin to a part in the circumferential direction including at least the upper surface side of the crimping portion; inserting the terminal into the terminal insertion portion before the curable resin is cured; and curing the curable resin.

[0031] It is desirable that the viscosity of the resin before curing is between 1 Pa·s and 300 Pa·s.

[0032] Furthermore, a method for manufacturing a terminal-inserted connector may also be a method for manufacturing a terminal-inserted connector, comprising the steps of: connecting a covered conductor to a terminal having a terminal body and a crimping portion at the crimping portion; applying a curable resin to a part of the circumferential direction including at least the upper surface of the crimping portion and curing it; applying a semi-solid material to the outer circumferential surface of the curable resin; and inserting the terminal into the terminal insertion portion of a connector housing.

[0033] According to the third invention, since the resin is applied to the terminal insertion portion of the housing before inserting the terminal, it is easy to determine whether the resin has been applied completely to the desired area. Furthermore, since the terminal is inserted into the terminal insertion portion of the housing before the resin hardens, the resin is spread inside the terminal insertion portion of the housing, ensuring that the terminal and the housing are tightly bonded by the curable resin.

[0034] Furthermore, if a release agent or curing inhibitor is applied to the inner surface of the terminal insertion area of ​​the connector housing beforehand, the shear adhesion force between the curable resin and the inner surface of the terminal insertion area can be reduced. This makes it possible to replace the terminals.

[0035] Furthermore, by adjusting the viscosity of the curable resin before curing to a range of 9 Pa·s to 300 Pa·s, the resin can be retained in a desired location inside the terminal insertion section between the time the resin is applied and when it hardens.

[0036] Furthermore, by applying a curable resin to a portion of the circumferential direction, including at least the upper surface of the crimping portion, and allowing it to harden, and then applying a semi-solid material to the outer surface of the curable resin, and then inserting the terminal into the terminal insertion portion of the connector housing, the shear adhesion force between the curable resin and the inner surface of the terminal insertion portion can be reduced. This makes it possible to replace the terminal. [Effects of the Invention]

[0037] According to the present invention, it is possible to provide a pre-inserted connector or the like that offers excellent maintainability and ensures high watertightness. [Brief explanation of the drawing]

[0038] [Figure 1] A perspective view showing connector 20 with terminals inserted. [Figure 2] A perspective view showing wire 1 with terminals. [Figure 3] (a) is a cross-sectional view showing the state before inserting the terminal-equipped wire 1 into the connector housing 25, and (b) is a cross-sectional view showing the state after inserting the terminal-equipped wire 1 into the connector housing 25. [Figure 4] Cross-sectional view of line AA in Figure 3(b). [Figure 5] (a) is a cross-sectional view showing the state before inserting the terminal-equipped wire 1 into the connector housing 25 in another manufacturing method, and (b) is a cross-sectional view showing the state after inserting the terminal-equipped wire 1 into the connector housing 25. [Modes for carrying out the invention]

[0039] Embodiments of the present invention will be described below with reference to the drawings. Figure 1 is a perspective view showing a terminal-inserted connector 20 (wire harness with connector). The terminal-inserted connector 20 consists of a connector housing 25 and a wire with terminals 1, etc. The connector housing 25 is provided with a plurality of terminal insertion parts 23. The terminals 5 of the wire with terminals 1 are inserted into the terminal insertion parts 23 provided in the connector housing 25.

[0040] Note that the shape of the connector housing 25 and the number and arrangement of the terminal insertion sections 23 are not limited to the illustrated example. Also, when there are multiple terminal insertion sections 23, it is not necessary to place terminal-equipped wires 1 in all of the terminal insertion sections 23, and some may be left empty.

[0041] Thus, a pre-inserted connector 20 only requires that at least one terminal 5 is inserted into the terminal insertion portion 23 of the connector housing 25. Furthermore, in the case of a pre-inserted connector 20, if the connector housing 25 has multiple terminal insertion portions 23, multiple terminals 5 connected to insulated wires 11 are inserted into the multiple terminal insertion portions 23, and the bundled insulated wires 11 constitute a wire harness with a connector.

[0042] Figure 2 is a perspective view showing the terminal-equipped wire 1 before it is inserted into the connector housing 25. The terminal-equipped wire 1 is constructed by connecting the terminal 5 to the insulated conductor 11.

[0043] The insulated conductor 11 consists of a conductor 13 made of, for example, aluminum or an aluminum alloy, and an insulated portion 15 that covers the conductor 13. That is, the insulated conductor 11 comprises an insulated portion 15 and a conductor 13 exposed from its tip. The conductor 13 is, for example, a stranded wire in which multiple strands are twisted together.

[0044] Terminal 5 is, for example, an open barrel type and is made of, for example, copper or a copper alloy. An insulated conductor 11 is connected to terminal 5. Terminal 5 is constructed by connecting the terminal body 3 and the crimping portion 17 via a transition portion 4. The transition portion 4, located between the crimping portion 17 and the terminal body 3, has an opening at the top.

[0045] The terminal body 3 is formed from a plate-like material of a predetermined shape into a cylindrical body with a rectangular cross-section. The terminal body 3 has an elastic contact piece inside, which is formed by folding the plate-like material into the rectangular cylindrical body. The terminal body 3 is connected by inserting a male terminal or the like from its front end. In the following description, an example is shown where the terminal body 3 is a female terminal that allows the insertion of an insertion tab (not shown) for a male terminal or the like, but in the present invention, the shape of the details of this terminal body 3 is not particularly limited. For example, instead of a female terminal body 3, an insertion tab for a male terminal may be provided.

[0046] The crimping portion 17 is the part that is crimped to the insulated conductor 11, and before crimping, the cross-sectional shape perpendicular to the longitudinal direction of the terminal 5 is a roughly U-shaped barrel. The crimping portion 17 of the terminal 5 consists of a conductor crimping portion 7 that crimps the conductor 13 exposed from the insulated portion 15 on the tip side of the insulated conductor 11, an insulated crimping portion 9 that crimps the insulated portion 15 of the insulated conductor 11, and a barrel section 8 between the conductor crimping portion 7 and the insulated crimping portion 9. In other words, the terminal 5 is connected to the insulated conductor 11 at the crimping portion 17.

[0047] At the tip of the insulated conductor 11, the insulation 15 is stripped away, exposing the internal conductor 13. As described above, the insulation 15 of the insulated conductor 11 is crimped by the insulation crimping portion 9 of the terminal 5, and the conductor 13, which is exposed after the insulation 15 is stripped away, is crimped by the conductor crimping portion 7. In other words, the conductor 13 and the terminal 5 are electrically connected at the conductor crimping portion 7. The end face of the insulation 15 is located in the barrel space 8 between the insulation crimping portion 9 and the conductor crimping portion 7.

[0048] A portion of the inner surface of the wire crimping section 7 is provided with serrations (not shown) in the width direction (perpendicular to the longitudinal direction). By forming these serrations, the oxide film on the surface of the wire 13 is more easily destroyed when the wire 13 is crimped, and the contact area with the wire 13 can be increased.

[0049] Next, a method for manufacturing the terminal-inserted connector 20 will be described. As mentioned above, first, the insulated conductor 11 is connected to the terminal 5, which has a terminal body 3 and a crimping portion 17, at the crimping portion 17 (see Figure 2). Next, a curable resin is applied to a part of the circumferential direction of the resulting terminal-equipped wire 1, including at least the upper surface of the crimping portion 17. For example, the curable resin is applied so as to cover the upper surface and part of the side surface of the crimping portion 17. The method of applying the curable resin is not particularly limited.

[0050] Figure 3(a) is a cross-sectional view of the connector housing 25 before inserting the terminal-equipped wire 1. The curable resin 19 is applied so as to cover at least the entire portion of the exposed wire 13 (including the barrel section 8 and the transition section 4 side).

[0051] The type of curable resin 19 is not particularly limited, but silicone resins and modified silicone resins can be used, with modified silicone resins being particularly desirable. Modified silicone resins have a certain degree of viscosity, so that the curable resin 19 does not immediately run off after application. For example, the viscosity of the curable resin 19 at room temperature before curing is preferably 1 Pa·s or more and 300 Pa·s or less, and more preferably 20 Pa·s or more and 100 Pa·s or less.

[0052] Furthermore, moisture-curing resins and anaerobic-curing resins can be used as the curable resin 19. It may also be cured by heating or ultraviolet irradiation. The curable resin 19 may also contain a curing accelerator. In addition, additives may be included as needed, to the extent that they do not impair the physical properties. Specifically, examples include curing agents, curing catalysts, inorganic fillers, antioxidants, metal deactivators (copper damage inhibitors), ultraviolet absorbers, ultraviolet opacifiers, flame retardant additives, processing aids (lubricants, waxes, etc.), carbon and other coloring pigments, flexibility imparters, impact resistance imparters, organic fillers, diluents (solvents, etc.), oscillating agents, various coupling agents, defoaming agents, leveling agents, etc. Since the purpose is corrosion prevention, it is preferable to add a rust inhibitor.

[0053] On the other hand, a release agent 27 is pre-applied to the inner surface of the terminal insertion portion 23 of the connector housing 25. Examples of release agents 27 include fluorine-based and silicone-based agents, and if the curable resin 19 is a modified silicone resin, nitrogen compounds, phosphorus compounds, sulfur compounds, etc., can be used.

[0054] Next, before the curable resin 19 hardens, the terminal 5 is inserted into the terminal insertion portion 23 of the connector housing 25. Figure 3(b) is a cross-sectional view showing the state in which the terminal 5 of the wire with terminal 1 is inserted into the terminal insertion portion 23 of the connector housing 25. In this state, the curable resin 19 is fluid. Therefore, when the terminal 5 is inserted into the terminal insertion portion 23, the curable resin 19 is pushed outwards toward the terminal 5 by the inner surface of the terminal insertion portion 23.

[0055] Figure 4 is a cross-sectional view of the terminal insertion portion 23 perpendicular to the insertion direction of the terminal 5, and is a cross-sectional view taken along line AA in Figure 3(b). As mentioned above, the curable resin 19 is applied to at least the upper surface of the crimping portion 17. When the terminal 5 is inserted into the terminal insertion portion 23 in this state, the curable resin 19 spreads out so as to wrap around the crimping portion 17. In addition, since the curable resin 19 is pressed against the crimping portion 17, the conductor 13 can be reliably covered by the curable resin 19.

[0056] In this state, the entire curable resin 19 can be cured to manufacture the terminal-inserted connector 20. As mentioned above, the curing method of the curable resin 19 is not particularly limited, but room temperature humidity curing or anaerobic curing is preferred, and humidity curing is more preferably preferred.

[0057] Furthermore, the release agent 27 only needs to be applied to at least the area in which the curable resin 19 is spread. For example, it is sufficient if it is applied to the upper surface and a part of the inner surface of the terminal insertion portion 23.

[0058] As shown in the figure, the terminal insertion portion 23 is coated with a curable resin 19 so that at least the upper surface of the crimping portion 17 is covered. In addition, a non-adhering portion 24 is formed between the other circumferential portion of the crimping portion 17 and the inner surface of the terminal insertion portion 23, where the curable resin 19 is not present. More specifically, the upper surface of the crimping portion 17 is bonded to the inner surface of the terminal insertion portion 23 by the curable resin 19, and the lower surface of the crimping portion 17 becomes the non-adhering portion 24.

[0059] The non-adhering portion 24 can be formed by adjusting the amount of curable resin 19 applied in advance so that the curable resin 19 does not spread around the entire circumference of the crimping portion 17 when the terminal 5 is inserted into the terminal insertion portion 23. In other words, the amount of curable resin 19 applied is adjusted so that the volume of the curable resin 19 is smaller than the difference between the internal space volume of the terminal insertion portion 23 and the volume of the crimping portion 17 to be inserted.

[0060] As shown in the figure, it is desirable that a gap be formed between the inner surface of the terminal insertion portion 23 and the crimping portion 17 in the non-adhering portion 24, but a gap is not necessarily required. If the inner surface of the terminal insertion portion 23 and the crimping portion 17 are not bonded by the curable resin 19 in the non-adhering portion 24, the lower surface of the crimping portion 17 and the terminal insertion portion 23 may be in contact. Also, if the release agent 27 is applied to the entire circumference of the inner surface of the terminal insertion portion 23, the non-adhering portion 24 may be omitted.

[0061] In this way, since the curable resin 19 and the terminal insertion portion 23 are not firmly bonded, the transmission of force between the connector housing 25 and the terminal 5 can be suppressed. Therefore, for example, stress caused by temperature changes due to differences in thermal expansion coefficients, and external forces (vibrations) transmitted from the connector housing 25 to the terminal 5 can be reduced.

[0062] Furthermore, as mentioned above, in the portion covered with the curable resin 19, including the upper surface of the crimping portion 17, a release agent 27 is applied between the inner surface of the terminal insertion portion 23 and the curable resin 19. As a result, the curable resin 19 and the terminal insertion portion 23 (connector housing 25) are not bonded together, or the bond is extremely weak. In other words, the crimping portion 17 and the terminal insertion portion 23 (connector housing 25) are not bonded together, or the bond is extremely weak, around the entire circumference of the crimping portion 17.

[0063] For example, the shear adhesion strength of the curable resin 19 to the crimping portion 17, as measured in accordance with JIS K6850 (1999), is preferably 0.2 MPa or higher. On the other hand, the shear adhesion strength of the curable resin 19 to the inner surface of the terminal insertion portion 23, as measured in accordance with JIS K6850 (1999), is preferably 0.001 MPa or lower. Thus, although the crimping portion 17 and the curable resin 19 are bonded together by the curing of at least a portion of the curable resin 19, the shear adhesion strength between the curable resin 19 and the inner surface of the terminal insertion portion 23 is lower than the shear adhesion strength between the curable resin 19 and the crimping portion 17.

[0064] Thus, although the curable resin 19 adheres firmly to the crimping portion 17, it does not adhere firmly to the inner surface of the terminal insertion portion 23 due to the release agent 27, making it possible to remove the terminal 5 from the connector housing 25. Even in this case, the curable resin 19 adheres tightly to the inner surface of the terminal insertion portion 23, ensuring high watertightness.

[0065] Alternatively, instead of the release agent 27, a hardening inhibitor may be applied to the inner surface of the terminal insertion portion 23. By applying the hardening inhibitor in this way, the hardening of the curable resin 19 in that area is inhibited. As a result, the curable resin 19 hardens at the contact point with the crimping portion 17, but remains unhardened at the contact point with the inner surface of the terminal insertion portion 23. In this way, by applying the release agent 27 or hardening inhibitor to the inner surface of the terminal insertion portion 23 of the connector housing 25 in advance, it is possible to suppress the hardening resin 19 from adhering firmly to the inner surface of the terminal insertion portion 23.

[0066] Furthermore, the material of the connector housing 25 itself may be a material that is poorly bonded to the curable resin 19. For example, if the curable resin 19 is a modified silicone resin, the connector housing 25, which is poorly bonded to the modified silicone resin, may be made of polyolefin materials such as polypropylene, polyethylene, or polybutene, or fluororesins such as tetrafluoroethylene. In this way, it is possible to suppress the curable resin 19 from adhering firmly to the inner surface of the terminal insertion part 23 without applying a release agent 27.

[0067] As described above, according to this embodiment, since the curable resin 19 is applied to the upper surface of the crimping portion 17 before inserting the terminal 5 into the terminal insertion portion 23, the application state of the curable resin 19 can be checked before insertion. Therefore, it is possible to detect terminals that have insufficient curable resin 19 application. Furthermore, since the terminal 5 with the uncured curable resin 19 applied is inserted into the terminal insertion portion 23, the curable resin 19 is spread between the inner wall of the terminal insertion portion 23 and the crimping portion 17. Therefore, even with a highly viscous curable resin 19, it can be reliably distributed to the exposed portion of the conductor 13, improving reliability without the use of special equipment and shortening manufacturing time.

[0068] Furthermore, the curable resin 19 adheres the exposed portion of the conductor 13 of the terminal 5 to the inner wall of the terminal insertion portion 23, improving watertightness and providing high corrosion resistance.

[0069] Furthermore, since the curable resin 19 has high shear adhesion to the crimping portion 17, high watertightness can be ensured, and because the shear adhesion to the inner surface of the terminal insertion portion 23 is small, the wire with terminal 1 can be removed from the connector housing 25 even after the terminal 5 has been inserted into the connector housing 25 and cured.

[0070] Next, a method for manufacturing the terminal-inserted connector 20 according to the second embodiment will be described. Figure 5(a) is a cross-sectional view of the state before the terminal-equipped wire 1 is inserted into the connector housing 25. In the following description, components that perform the same function as in the first embodiment are denoted by the same reference numerals as in Figures 1 to 4, and redundant explanations are omitted.

[0071] In the second embodiment, similar to the first embodiment, the insulated conductor 11 is first connected at the crimp portion 17 of the terminal 5, and the curable resin 19 is applied so as to cover the entire portion of the exposed conductor 13 (including the barrel-to-barrel portion 8 and the transition portion 4 side). In this state, the curable resin 19 is allowed to harden.

[0072] Next, a semi-solid material 29 is applied to the outer surface of the fully cured curable resin 19 (for example, a part of the outer surface including the top surface). Examples of semi-solid materials 29 include non-curing adhesives, greases, and elastomers, and if the grease contains a rust inhibitor, corrosion resistance can be enhanced.

[0073] Next, with the semi-solid material 29 applied (not yet hardened), the terminal 5 is inserted into the terminal insertion portion 23 of the connector housing 25. Figure 5(b) is a cross-sectional view showing the state in which the terminal 5 of the wire with terminal 1 has been inserted into the terminal insertion portion 23 of the connector housing 25. In this state, the semi-solid material 29 is fluid. Therefore, when the terminal 5 is inserted into the terminal insertion portion 23, the semi-solid material 29 is pushed outwards toward the terminal 5 by the inner surface of the terminal insertion portion 23, and the semi-solid material 29 spreads out so as to wrap around the crimping portion 17.

[0074] Since the semi-solid material 29 hardly hardens, the semi-solid material 29 and the terminal insertion portion 23 (connector housing 25) are either not bonded or bonded very weakly. In other words, the crimping portion 17 and the terminal insertion portion 23 (connector housing 25) are either not bonded or bonded very weakly around the entire circumference of the crimping portion 17. Thus, by placing the semi-solid material 29 on the outer surface of the curable resin 19, the crimping portion 17 and the curable resin 19 are bonded, but the shear bond between the semi-solid material 29 and the inner surface of the terminal insertion portion 23 is smaller than the shear bond with the crimping portion 17.

[0075] Even in this manner, it is possible to remove the terminal 5 from the connector housing 25. In this case as well, the semi-solid material 29 adheres closely to the outer surface of the curable resin 19 and the inner surface of the terminal insertion part 23, thus ensuring high watertightness.

[0076] As described above, the second embodiment provides the same effects as the first embodiment. In this way, since the curable resin 19 hardens as a whole, the curable resin 19 and the crimping portion 17 are firmly bonded, and the semi-solid material 29 is placed between the inner surface of the terminal insertion portion 23 and the curable resin 19, and the semi-solid material 29 adheres closely to the inner surface of the terminal insertion portion 23 and the outer surface of the curable resin 19, thus providing high watertightness.

[0077] In the embodiments described above, the crimping portion 17 is of the so-called open barrel type, but the shape of the crimping portion is not particularly limited. Also, the materials of the terminal 5 and the conductor 13 are not limited to the examples described above, and other combinations of metals may be used. [Examples]

[0078] (Manufacturing method A) Connectors with pre-inserted terminals were fabricated and various evaluations were performed. In manufacturing method A, a coated wire (400 mm in length) with a conductor made of multiple twisted aluminum strands was used. The overall cross-sectional diameter of the conductor is circular with a diameter of 1.6 mm. The coating layer of the coated wire is made of polyvinyl chloride.

[0079] The insulated conductor was electrically connected to a copper terminal, and a curable resin was applied to the upper surface of the crimped area to a thickness of approximately 1000 μm. The curable resin to be applied will be described later. Immediately afterward, the uncured part was inserted into the connector housing and left in an atmosphere at 25°C and 70% relative humidity for 120 hours to cure.

[0080] (Manufacturing method B) On the other hand, in manufacturing method B, a covered wire (400 mm in length) with a conductor made of multiple twisted aluminum strands was also used. The overall diameter of the conductor was 1.6 mm, making it circular. The covering layer of the covered wire was made of polyvinyl chloride.

[0081] On the other hand, in manufacturing method B, the insulated conductor was electrically connected to a copper terminal, and resin was applied to the upper surface of the crimped part to a thickness of approximately 1000 μm. The resin was then left to cure in an atmosphere at 25°C and 70% relative humidity for 120 hours. After confirming that the resin had completely cured, it was inserted into the connector housing.

[0082] (Curable resin A) As the curable resin A, we used "EP001K" (product name) manufactured by Cemedyne Co., Ltd. "EP001K" is a two-component type and consists of liquid A (solvent-free (solid content concentration 100% by mass)) containing epoxy resin and a curing catalyst (organotin compound) for modified silicone resin (room temperature moisture curing type silicone resin), and liquid B (solvent-free (solid content concentration 100% by mass)) containing the modified silicone resin and an epoxy resin curing agent (modified polyamine). Liquid A / Liquid B was mixed at a ratio of 100 / 100 (parts by mass) and used for bonding.

[0083] (Curable resin B) As the curable resin B, we used "Super X No. 8008" (product name) manufactured by Cemedyne Co., Ltd. "Super X No. 8008" is a one-component curable resin composition (solvent-free (solid content concentration 100% by mass)) containing a polyfunctional (meth)acrylate compound, a modified silicone resin (room temperature moisture curing type silicone resin), and a curing catalyst for the modified silicone resin (dibutylsulcanized laurate).

[0084] (Curable resin C) As the curable resin B, "KE-3495" (product name) manufactured by Shin-Etsu Silicone Co., Ltd. was used. "KE-3495" is a curable resin composition (solvent-free (solid content concentration 100% by mass)) containing a silicone resin (room temperature moisture curing type silicone resin) and a curing catalyst for the silicone resin (dibutylsulose laurylate).

[0085] (Shear adhesion strength measurement) The shear adhesion strength was measured in accordance with JIS K6850 (1999). Specifically, a copper test specimen measuring 25.0 mm in width, 100.0 mm in length, and 1.6 mm in thickness was prepared. On one side, the area from one end of the specimen up to 12.5 mm was de-rusted with sandpaper, and then degreased with methyl ethyl ketone (MEK) to obtain a surface-treated copper test specimen.

[0086] Each of the curable resins described above was applied to the surface-treated area of ​​the surface-treated copper test piece, and the surface-treated area of ​​another surface-treated copper test piece was bonded to this applied surface. At this time, the test piece was fixed with a jig so that the thickness of the adhesive layer derived from the curable resin was approximately 0.2 mm, and any excess curable resin was wiped off. After that, the test sample was obtained by leaving it in an atmosphere of 23°C and 50% relative humidity for 7 days.

[0087] In addition, test samples were obtained in the same manner using 3.0 mm thick polyvinyl chloride test specimens, polybutylene terephthalate, and polytetrafluoroethylene test specimens, with the surface treatment being only degreasing with MEK. For the polybutylene terephthalate test specimens, test samples were also prepared in which a fluorine-based release agent (Type R) manufactured by Ichinen Chemicals was applied to the surface after surface treatment, followed by the application of a curable coating agent.

[0088] Subsequently, under conditions of 23°C and 50% relative humidity, the test sample was placed in a Shimadzu Autograph AG-Xplus and the breaking force was measured when the loading speed was set to break in 65 seconds ± 20 seconds. Five measurements were taken, and the average breaking force was divided by the bonding area of ​​the test specimen to determine the shear bonding strength. The results are shown in Table 1.

[0089] [Table 1]

[0090] All of the curable resins A to C exhibited shear adhesion strength of 2.0 MPa or higher to copper, polyvinyl chloride, and polybutylene terephthalate, respectively. However, applying a release agent to polybutylene terephthalate resulted in a shear adhesion strength of 0.001 MPa or less. Furthermore, for polytetrafluoroethylene, which exhibits poor adhesion to curable resins A to C, a shear adhesion strength of 0.001 MPa or less was achieved without the application of a release agent.

[0091] (Corrosion resistance test) The corrosion resistance test was conducted as follows: A 100 cm² area connected to the power supply's ground was immersed in a 1% sodium chloride aqueous solution. 2 The copper electrodes were immersed in water to a depth of 65 cm, and a sample of a connector with terminals inserted and connected to the positive terminal of the power supply was immersed in water to a depth of 60 cm, with the two positioned opposite each other. Then, 12V was applied for 6 hours and left to stand.

[0092] After the corrosion resistance test, the appearance of the crimped area was observed using a microscope. Items with no defects in the metal portion of the crimped area were marked with a circle (○), while those with defects were marked with an "X" (×).

[0093] (Cold cycle test) The prepared connectors with inserted terminals were placed in a thermal cycling test machine and held at 125°C for 15 minutes, followed by a period of 15 minutes at -40°C. This thermal cycling cycle was repeated 240 times to constitute the thermal cycling test. After this thermal cycling test, the "corrosion resistance test" described above was performed, and the appearance was evaluated in the same manner as in the corrosion resistance test.

[0094] Furthermore, after the thermal cycling test, the above-mentioned "corrosion resistance test" was conducted. For samples taken before the thermal cycling test, and after both the thermal cycling test and the corrosion resistance test, a resistance meter was used to electrically connect the terminal side of the connector with the wire end opposite the terminal side, and the resistance was measured. The resistance increase was defined as the difference between the resistance value after the corrosion resistance test and the resistance value before the thermal cycling test. A resistance increase of 1.0Ω or less was marked as ○, and a resistance increase exceeding 1.0Ω was marked as ×.

[0095] (Continuous heat resistance test) The manufactured connectors with inserted terminals were placed in a constant temperature chamber and left at 125°C for 120 hours to conduct a continuous heat resistance test. Subsequently, the "corrosion resistance test" described above was performed, and the appearance was evaluated in the same manner as in the corrosion resistance test.

[0096] Furthermore, after the continuous heat resistance test, the above-mentioned "corrosion resistance test" was conducted. For samples taken before the continuous heat resistance test, and after both the continuous heat resistance test and the corrosion resistance test, a resistance meter was used to electrically connect the terminal side of the connector with the wire end opposite the terminal side, and the resistance was measured. The resistance increase was defined as the difference between the resistance value after the corrosion resistance test and the resistance value before the continuous heat resistance test. A resistance increase of 1.0Ω or less was marked as ○, and a resistance increase exceeding 1.0Ω was marked as ×.

[0097] (Sampling test) We attempted to determine the orientation of the terminal-attached wires from the manufactured connectors with pre-inserted terminals using a special extraction tool. Those that could be extracted were marked with a circle (○), and those that could not be extracted were marked with a cross (×).

[0098] (Example 1) A connector with pre-inserted terminals was manufactured using manufacturing method A. In Example 1, curable resin A was used as the resin applied to the crimping portion. After applying Ichinen Chemicals' fluorine-based release agent R to the inner wall of the terminal insertion portion of the connector housing made of polybutylene terephthalate, the terminals were inserted into the terminal insertion portion using curable resin A before curing.

[0099] (Example 2) A connector with pre-inserted terminals was manufactured using manufacturing method A. In Example 2, curable resin B was used as the resin applied to the crimping portion. Ichinen Chemicals' fluorine-based release agent Type R was pre-applied to the inner wall of the terminal insertion portion of the connector housing made of polybutylene terephthalate, and then the terminals were inserted into the terminal insertion portion using curable resin B before curing.

[0100] (Example 3) A connector with pre-inserted terminals was manufactured using manufacturing method A. In Example 3, a curable resin C was used as the resin applied to the crimping portion. A release agent fluorine-based type R manufactured by Ichinen Chemicals was applied to the inner wall of the terminal insertion portion of the connector housing made of polybutylene terephthalate beforehand, and then the terminals were inserted into the terminal insertion portion using curable resin C before it cured.

[0101] (Example 4) A connector with pre-inserted terminals was manufactured using manufacturing method A. In Example 4, curable resin A was used as the resin to be applied to the crimping portion. After applying curable resin A, the terminals were inserted into the terminal insertion portion of a polytetrafluoroethylene connector housing before curing resin A.

[0102] (Example 5) A connector with pre-inserted terminals was manufactured using manufacturing method A. In Example 5, curable resin B was used as the resin to be applied to the crimping portion. After applying curable resin B, the terminals were inserted into the terminal insertion portion of a polytetrafluoroethylene connector housing before the curable resin B hardened.

[0103] (Example 6) A connector with pre-inserted terminals was manufactured using manufacturing method A. In Example 6, a curable resin C was used as the resin to be applied to the crimping portion. After applying the curable resin C, the terminals were inserted into the terminal insertion portion of a polytetrafluoroethylene connector housing before the curable resin C hardened.

[0104] (Comparative Example 1) A connector with pre-inserted terminals was manufactured using manufacturing method B. In Comparative Example 1, curable resin A was used as the resin applied to the crimping portion. After applying curable resin A, the terminals were inserted into the terminal insertion portion of the connector housing made of polybutylene terephthalate after curing of curable resin A.

[0105] (Comparative Example 2) A connector with pre-inserted terminals was manufactured using manufacturing method B. In Comparative Example 2, curable resin B was used as the resin applied to the crimping portion. After applying curable resin B, the terminals were inserted into the terminal insertion portion of the polybutylene terephthalate connector housing after curing of curable resin B.

[0106] (Comparative Example 3) A connector with pre-inserted terminals was manufactured using manufacturing method B. In Comparative Example 3, a curable resin C was used as the resin applied to the crimping portion. After applying the curable resin C, the terminals were inserted into the terminal insertion portion of the connector housing made of polybutylene terephthalate after the curable resin C had hardened.

[0107] (Comparative Example 4) A connector with pre-inserted terminals was manufactured using manufacturing method A. In Comparative Example 4, curable resin A was used as the resin applied to the crimping portion. After applying curable resin A, the terminals were inserted into the terminal insertion portion of a connector housing made of polybutylene terephthalate before curing of curable resin A.

[0108] (Comparative Example 5) A connector with pre-inserted terminals was manufactured using manufacturing method A. In Comparative Example 5, curable resin B was used as the resin applied to the crimping portion. After applying curable resin B, the terminals were inserted into the terminal insertion portion of a connector housing made of polybutylene terephthalate before curing of curable resin B.

[0109] (Comparative Example 6) A connector with pre-inserted terminals was manufactured using manufacturing method A. In Comparative Example 6, a curable resin C was used as the resin applied to the crimping portion. After applying the curable resin C, the terminals were inserted into the terminal insertion portion of a connector housing made of polybutylene terephthalate before the curable resin C hardened.

[0110] As described above, Examples 1 to 6 employ a new manufacturing method in which the connector is inserted before the resin hardens, and either a release agent for the curable resin is applied to the terminal insertion part, or a connector housing with poor adhesion to the curable resin is used. On the other hand, Comparative Examples 1 to 3 employ a conventional manufacturing method in which the connector is inserted after the resin hardens. Comparative Examples 4 to 6 also employ a new manufacturing method in which the connector is inserted before the resin hardens, but without the application of a release agent. The results are shown in Tables 2 to 3.

[0111] [Table 2]

[0112] [Table 3]

[0113] As shown in Tables 2 and 3, in Examples 1-6, both the cold-heat cycle and continuous heat resistance were effectively suppressed because the insertion space of the housing and the crimped portion were tightly bonded via the curable resin, allowing the exposed portion of the aluminum conductor to be sufficiently isolated from the outside, thereby preventing metal damage and an increase in resistance. Furthermore, all of Examples 1-6 demonstrated good extractability.

[0114] On the other hand, in Comparative Examples 1-3, since the terminals were inserted into the connector housing after the resin cured, when exposed to thermal cycles or high temperatures for extended periods, defects in the metal parts and an increase in resistance were observed. This is thought to be due to the effects of heat, which caused cracks and peeling in some parts of the resin, reducing the watertightness of the crimped area. Furthermore, because the resin was highly viscous, it was difficult for the resin to spread evenly, which may have resulted in defects in the coating or areas where the coating was extremely thin and had low insulation properties, such as on the sides of the crimped area.

[0115] Furthermore, Comparative Examples 4-6, which employed a new manufacturing method in which the terminals were inserted into the connector housing before the resin cured, were able to effectively suppress metal part defects and increases in resistance even when exposed to thermal cycles or prolonged exposure to high temperatures. However, because the crimped portion was bonded to the terminal insertion portion, it was not possible to remove the wire with the terminal attached.

[0116] Although embodiments of the present invention have been described above with reference to the attached drawings, the technical scope of the present invention is not limited to the embodiments described above. It is clear to those skilled in the art that various modifications or alterations can be conceived within the scope of the technical idea described in the claims, and these will naturally also fall within the technical scope of the present invention. [Explanation of Symbols]

[0117] 1…Electric wire with terminals 3…Terminal body 4...Transition section 5… Terminals 7…Wire crimping section 8... Barrel section 9......Sheathing crimping part 11...Insulated wire 13……Conducting wire 15... Covering part 17… Crimping section 19......Curable resin 20… Connector with terminals inserted 23… Terminal insertion section 25… Connector housing 27… Release agent

Claims

1. A terminal-inserted connector in which at least one terminal is inserted into the terminal insertion portion of the connector housing, The terminal has a terminal body and a crimping portion, and the terminal is connected to the insulated conductor at the crimping portion. The crimped portion is covered with a curable resin so as to cover at least its upper surface, A terminal-inserted connector characterized in that, at least a portion of the curable resin hardens, thereby bonding the crimping portion and the curable resin, and the shear adhesive force between the curable resin and the inner surface of the terminal insertion portion is smaller than the shear adhesive force between the curable resin and the crimping portion.

2. The terminal-inserted connector according to claim 1, characterized in that the curable resin is cured at the contact portion with the crimping portion and uncured at the contact portion with the inner surface of the terminal insertion portion.

3. The terminal-inserted connector according to claim 1, characterized in that the curable resin is fully cured and a release agent is applied between the inner surface of the terminal insertion portion and the curable resin.

4. The terminal-inserted connector according to claim 1, characterized in that the curable resin is fully cured, and a semi-solid material is disposed between the inner surface of the terminal insertion portion and the curable resin.

5. The terminal-inserted connector according to claim 1, characterized in that the shear adhesive force of the curable resin to the crimped portion, as measured in accordance with JIS K6850 (1999), is 0.2 MPa or more, and the shear adhesive force of the curable resin to the inner surface of the terminal insertion portion, as measured in accordance with JIS K6850 (1999), is 0.001 MPa or less.

6. A wire harness with a connector using a terminal-inserted connector according to any one of claims 1 to 5, wherein the connector housing has a plurality of terminal insertion portions, and a plurality of terminals connected to the insulated conductors are inserted into the terminal insertion portions.

7. A method for manufacturing a connector with terminals already inserted, A terminal having a terminal body and a crimping portion, comprising the steps of connecting an insulated conductor at the crimping portion, A step of applying a release agent or hardening inhibitor to the inner surface of the terminal insertion part of the connector housing, A step of applying a curable resin to a part of the circumferential direction, including at least the upper surface of the crimped portion, Before the curable resin hardens, the process involves inserting the terminal into the terminal insertion section. A step of curing the aforementioned curable resin, A method for manufacturing a terminal-inserted connector, characterized by comprising the following:

8. The method for manufacturing a terminal-inserted connector according to claim 7, characterized in that the viscosity of the curable resin before curing is 1 Pa·s or more and 300 Pa·s or less.

9. A method for manufacturing a connector with terminals already inserted, A terminal having a terminal body and a crimping portion, comprising the steps of connecting an insulated conductor at the crimping portion, A step of applying a curable resin to a part of the circumferential direction, including at least the upper surface of the crimped portion, and curing it, A step of applying a semi-solid material to the outer surface of the curable resin, The process of inserting the terminal into the terminal insertion section of the connector housing, A method for manufacturing a terminal-inserted connector, characterized by comprising the following:

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