INJECTION-MOLDED WIRE HARNESS AND MOLDING METHOD

Abstract

An injection molded wire harness and a molding method. The wire harness includes a terminal and at least one conductor. One end of the terminal is connected to an electrical circuit of an electrical device, and the other end of the terminal is connected to the conductor. The wire harness is provided with a protective layer which is injection-molded and wraps the conductor, and at least one positioning device that is injection molded for fixing the position of the wire harness and/or at least one sealing device that is injection molded for waterproofing. The method can reduce manual operation, improve consistency of wire harness products, reduce production cost of wire harness products, and prolong the service life of the wire harness.

Claims

1. An injection molded wire harness comprising a terminal and at least one conductor, wherein one end of the terminal is connected to an electrical circuit of an electrical device, and the other end of the terminal is connected to the conductor; the wire harness is provided with a protective layer which is injection molded and wraps the conductor, and at least one positioning device that is injection molded for fixing the position of the wire harness and/or at least one sealing device that is injection molded for waterproofing.

2. The injection molded wire harness according to claim 1, wherein an insulation layer is arranged outside the conductor, and the protective layer is injection molded outside the insulation layer.

3. The injection molded wire harness according to claim 1, wherein the positioning device comprises a first fixing device connected to the wire harness, and a fitting device matched and connected with a mounting end for installing the wire harness, with the fitting device being connected to the first fixing device.

4. The injection molded wire harness according to claim 3, wherein the first fixing device is a cylindrical structure, and an inner wall of the cylindrical structure is fitted with an outer surface of the protective layer and wraps the outer surface of the protective layer.

5. The injection molded wire harness according to claim 3, wherein the fitting device is a columnar structure having an inverted tooth structure on the outer periphery of the columnar structure.

6. The injection molded wire harness according to claim 3, wherein the fitting device comprises a clip-shaped structure.

7. The injection molded wire harness according to claim 6, wherein the clip-shaped structure is provided with a groove in which barbs are arranged on both inner side walls.

8. The injection molded wire harness according to claim 3, wherein the fitting device comprises a circular ring structure or a C-shaped ring structure.

9. The injection molded wire harness according to claim 3, wherein the positioning device is a plastic member processed by injection molding.

10. The injection molded wire harness according to claim 1, wherein the sealing device comprises a second fixing device connected to the wire harness, and a waterproof device, one end of which is connected to the second fixing device.

11. The injection molded wire harness according to claim 10, wherein the second fixing device is a cylindrical structure, and an inner wall of the cylindrical structure is fitted with an outer surface of the protective layer and wraps the outer surface of the protective layer.

12. The injection molded wire harness according to claim 10, wherein the sealing device is a rubber member processed by injection molding.

13. The injection molded wire harness according to claim 1, wherein the wire harness is further provided with at least one sheath that is mutually inserted with an electrical device, and the terminal is fitted in a corresponding hole of the sheath.

14. The injection molded wire harness according to claim 13, wherein the sheath is integrally injection molded onto at least the terminal.

15. The injection molded wire harness according to claim 1, wherein the conductor is a solid conductor, a flat conductor, or a conductor composed of multiple strands of wire.

16. (canceled)

17. (canceled)

18. The injection molded wire harness according to claim 1, wherein when the at least one conductor is more than two conductors belonging to the same circuit, the conductors on a non-terminal side are connected according to a requirement of the circuit by crimping or welding to form a conductor connection point.

19. The injection molded wire harness according to claim 18, wherein the conductor connection point is wrapped and sealed by integral injection molding.

20. A method of preparing the wire harness according to claim 1, comprising: A. preparing a semi-finished wire harness; B. putting required raw materials into an injection molding equipment and drying them, then putting the semi-finished wire harness prepared in the step A into an injection mold; or putting the semi-finished wire harness prepared in the step A into an injection mold, and then putting required raw materials into an injection molding equipment and drying them; C. starting the injection molding equipment to heat and melt the raw materials, and injecting the raw materials into the injection mold for molding.

21. The method according to claim 20, wherein, the method further comprises one of: in the case of a single conductor, preparing the semi-finished wire harness comprises connecting the terminal to the conductor using a crimping or welding apparatus; the protective layer or the positioning device or the sealing device is injection molded in accordance with the step B to the step C; and in the case of more than one conductor, preparing the semi-finished wire harness comprises connecting the terminal to the conductors using a crimping or welding apparatus; the protective layer is injection molded outside the conductors arranged at intervals in accordance with the step B to the step C, and the positioning device or the sealing device is injection molded in accordance with the step B to the step C; and in the case of more than two conductors belonging to the same circuit, preparing the semi-finished wire harness comprises connecting the conductors according to a requirement of the circuit by crimping or welding to form a conductor connection point; a wire harness protection device is injection molded firstly in accordance with the step B to the step C, then the protective layer is injection molded and finally the positioning device or the sealing device is injection molded in accordance with the step B to the step C.

22. (canceled)

23. (canceled)

24. The method according to claim 20, wherein, the method further comprises one of: when the semi-finished wire harness is provided with a sheath, the terminal connected to the conductor is inserted into a corresponding hole of the sheath, and then an injection molding is performed; or the semi-finished wire harness is injection molded firstly, and then the terminal connected to the conductor is inserted into a corresponding hole of the sheath; and the semi-finished wire harness is put into the injection mold, and a sheath is integrally injection molded onto at least the terminal.

25. (canceled)

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0060] FIG. 1 is a schematic view of a wire harness with a single conductor, without sheath, and with a positioning device and a sealing device according to the present disclosure.

[0061] FIG. 2 is a schematic view of a wire harness with multiple conductors, with a sheath, and with a positioning device and a sealing device according to the present disclosure.

[0062] FIG. 3A is a cross-sectional schematic view of a wire harness with a single conductor and a protective layer according to the present disclosure.

[0063] FIG. 3B is a cross-sectional schematic view of a wire harness with multiple conductors arranged in a linear direction, and with a protective layer according to the present disclosure.

[0064] FIG. 3C is a cross-sectional schematic view of a wire harness with multiple conductors arranged in a circumferential direction, and with a protective layer according to the present disclosure.

[0065] FIG. 3D is a cross-sectional schematic view of a wire harness with multiple conductors, insulation layers, and a protective layer according to the present disclosure.

[0066] FIG. 4 is a schematic view of a wire harness with multiple conductors and conductor connection points according to the present disclosure.

[0067] FIG. 5 is a structural schematic diagram of a positioning device according to the present disclosure.

[0068] FIG. 6 is a schematic view of a fitting device with an inverted tooth structure.

[0069] FIG. 7 is a schematic view of a fitting device with a clip-shaped structure.

[0070] FIG. 8 is a schematic view of a fitting device with a C-shaped ring structure.

[0071] FIG. 9A is a structural schematic diagram of a wire harness with a sealing device matched with a via hole on a partition plate according to the present disclosure.

[0072] FIG. 9B is a partial sectional structural schematic diagram of FIG. 9A.

[0073] FIG. 10 is a structural schematic diagram of a sealing device for a conductor, a terminal and a protective layer according to the present disclosure.

[0074] FIG. 11 is a structural schematic diagram of a sealing device for a sheath according to the present disclosure.

[0075] FIG. 12 is a structural schematic diagram of an integrally molded sheath according to the present disclosure.

[0076] In the drawings, the reference numerals are: 1. terminal; 2. conductor; 3. insulation layer; 4. sealing device; 5. positioning device; 6. sheath; 7. protective layer; 8. wire harness protection device; 9. waterproof device; 10. second fixing device; 11. fitting device; 12. first fixing device; 13. waterproof jacket; 14. locking groove.

DETAILED DESCRIPTION

[0077] In order to further illustrate the technical features and effects of the present disclosure for achieving the intended object of the present disclosure, hereinafter specific embodiments, structures, features and functions thereof according to the present disclosure will now be described in detail in conjunction with the drawings and exemplary embodiments as follows.

The First Embodiment

[0078] As shown in FIGS. 1 and 3A, the wire harness includes a single conductor 2, and both ends of the conductor 2 are respectively connected to a terminal 1. The terminal 1 is a copper terminal, which is made of a copper alloy with a copper content of 60%, thereby ensuring good electrical conductivity and workability of the copper terminal. The surface of the terminal 1 can be plated with one selected from the group of nickel, cadmium, zirconium, chromium, cobalt, manganese, aluminum, tin, titanium, zinc, copper, silver, and gold. The plating can slow down the corrosion of the terminal and prolong the service life of the terminal. One end of the terminal 1 is connected to the conductor 2, and the other end of the terminal 1 is connected to an electrical circuit of an electrical device when in use. In this embodiment, the conductor 2 is composed of multiple core wires, and the cross section of the multiple core wires is circular. In other embodiments, the conductor 2 may also be a solid conductor or a flat conductor. The cross section of the conductive portion of the conductor 2 may also be elliptical, polygonal, wavy, or profiled. The wire harness is provided with a protective layer 7 which is injection molded and wraps the conductor 2. The protective layer 7 is made of plastic or rubber. In this embodiment, the material of the protective layer 7 is PVC. The wire harness is also provided with at least one positioning device 5 that is injection molded for fixing the position of the wire harness and/or at least one sealing device 4 that is injection molded for waterproofing.

[0079] The conductor 2 may be an externally purchased electric wire with an insulation layer 3, and the protective layer 7 is injection molded outside the insulation layer 3. Alternatively, the protective layer 7 may be directly injection molded outside the conductor 2. As shown in FIG. 3A, the single conductor 2 is arranged in the middle, and the protective layer 7 is injection molded on the periphery of the single conductor 2.

[0080] After the conductor 2 is cut by a predetermined length, both ends of the conductor 2 are connected to the terminal 1 by crimping or welding to obtain a semi-finished product. The semi-finished product is then put into an injection mold, and the protective layer 7, the positioning device 5 and the sealing device 4 are formed by injection molding according to predetermined dimensions. The specific injection molding method is as follows:

[0081] A. preparing a semi-finished wire harness;

[0082] B. putting the required raw materials into an injection molding equipment and drying them, then putting the semi-finished wire harness prepared in the step A into an injection mold; or putting the semi-finished wire harness prepared in the step A into an injection mold, and then putting the required raw materials into an injection molding equipment and drying them;

[0083] C. starting the injection molding equipment to heat and melt the raw materials, and injecting the raw materials into the injection mold for molding.

[0084] The material of the positioning device 5 is PA66, and in other embodiments, the positioning device 5 may be a plastic member processed by injection molding. As shown in FIG. 5, the positioning device 5 includes a first fixing device 12 connected to the wire harness and a fitting device 11 matched and connected with a mounting end for installing the wire harness. The fitting device 11 is connected to the first fixing device 12. The first fixing device 12 is a cylindrical structure, and an inner wall of the cylindrical structure is fitted with an outer surface of the protective layer 7 and wraps the outer surface of the protective layer 7. The specific structure of the fitting device 11 may include an inverted tooth structure which is mutually inserted with a mounting hole for installing the wire harness. Specifically, the fitting device is a columnar structure, and the outer periphery of the columnar structure is provided with an inverted tooth structure which is mutually inserted and snapped with the mounting hole (as shown in FIG. 6). In other embodiments, the fitting device may also be provided with a clip-shaped structure (as shown in FIG. 7) for matching and connecting with a plate. Specifically, the fitting device 11 is provided with a groove, on the two inner side walls of which barbs for latching with the plate are provided. Alternatively, the fitting device 11 is provided with a circular ring structure or a C-shaped ring structure for matching with a tubular or cylindrical structure (as shown in FIG. 8).

[0085] It should be noted that, the material of the sealing device 4 is EPDM, and in other embodiments, the sealing device 4 may be a rubber member processed by injection molding. Generally, when installed, the wire harness needs to pass through some via holes on a partition plate located between dry and wet areas. In order to prevent the water in the wet areas from entering into the dry areas, as shown in FIGS. 9A and 9B, the sealing device 4 in this embodiment includes a second fixing device 10 connected to the wire harness and a waterproof device 9, and the waterproof device 9 is connected to the second fixing device 10. The second fixing device 10 is a cylindrical structure, and an inner wall of the cylindrical structure is fitted with an outer surface of the protective layer 7 and wraps on the outer surface of the protective layer 7. The waterproof device 9 includes a waterproof jacket 13 having one end connected to the second fixing device 10, and a locking groove 14 connected to the other end of the waterproof jacket 13 and used for fitting with a waterproof hole.

[0086] In this embodiment, when the wire harness is in a wet area, the sealing device is provided between the protective layer 7, the conductor 2 and the terminal 1 of the wire harness, to seal and wrap the protective layer 7, the conductor 2 and the terminal 1. As shown in FIG. 10, the sealing device 4 is injection molded on the conductor 2, a connection position between the terminal 1 and the conductor 2, and the outside of the protective layer. The portion of the sealing device 4 corresponding to the conductor 2 and the terminal 1 is the waterproof device 9, and the portion of sealing device 4 corresponding to the protective layer 7 is the second fixing device 10.

The Second Embodiment

[0087] As shown in FIGS. 2, 3B and 3C, the wire harness includes more than one conductor 2, and both ends of each of the conductors 2 are respectively connected to a terminal 1. The surface of the terminal 1 can be plated with one selected from the group of nickel, cadmium, zirconium, chromium, cobalt, manganese, aluminum, tin, titanium, zinc, copper, silver, and gold. The conductor 2 and the terminal 1 in this embodiment are the same as those in the First Embodiment, so will not be described in detail. The difference between this embodiment and the First Embodiment is that the wire harness is further provided with at least one sheath 6 for mutually inserting with an electrical device. After the conductor 2 is connected to the terminal 1, the terminal 1 is fitted in the sheath 6, and different terminals 1 correspond to different holes of the sheath 6 according to design requirements, so as to connect different circuits, and also protect the terminal 1 from damage. The sheath 6 is integrally injection molded onto at least the terminal 1.

[0088] After the multiple conductors 2 are cut respectively by a predetermined length, both ends of each conductor 2 are connected to the terminal 1 by crimping or welding to obtain a semi-finished product. The semi-finished product is then put into an injection mold, and the protective layer 7, the positioning device 5 and the sealing device 4 are formed by injection molding according to predetermined dimensions. Specifically, the wire harness protective layer 7 is injection molded firstly, then the wire harness protection device 8 is injection molded and finally the positioning device 5 or the sealing device 4 is injection molded.

[0089] In this embodiment, when the wire harness is in a wet area, the sealing device 4 is provided between the protective layer 7, the conductor 2 and the terminal 1 of the wire harness, to seal and wrap the protective layer 7, the conductor 2 and the terminal 1. As shown in FIG. 10, the sealing device 4 is injection molded on the conductor 2, a connection position between the terminal 1 and the conductor, and the outside of the protective layer 7. The portion of the sealing device 4 corresponding to the conductor 2 and the terminal 1 is the waterproof device 9, and the portion of the sealing device 4 corresponding to the protective layer 7 is the second fixing device 10.

[0090] The specific injection molding method is as follows:

[0091] A. preparing a semi-finished wire harness;

[0092] B. putting the required raw materials into an injection molding equipment and drying them, then putting the semi-finished wire harness prepared in the step A into an injection mold; or putting the semi-finished wire harness prepared in the step A into an injection mold, and then putting the required raw materials into an injection molding equipment and drying them;

[0093] C. starting the injection molding equipment to heat and melt the raw materials, and injecting the raw materials into the injection mold for molding.

[0094] The parameters of injection molding include heating temperature, cooling temperature, injection molding pressure, and injection molding time. The injection molding operation is performed according to the conventional operation method of the existing injection molding equipment. Requirements are that the injection-molded products shall be free of defects such as impurities, pits, flash, pores, and etc.

[0095] As shown in FIGS. 3B and 3C, the multiple conductors 2 are arranged in the middle, and the protective layer 7 is molded around the periphery of the multiple conductors 2. Therefore, in one aspect, the multiple conductors 2 are bound together by the protective layer 7 to prevent the conductors 2 from scattering during the wire harness installation, and in the other aspect, the multiple conductors 2 are insulated and isolated by the protective layer 7 to prevent the multiple conductors 2 from being short-circuited to each other and from being damaged by an external force such as scraping after the wire harness is installed. In this embodiment, the conductor 2 is a solid conductor or a flat conductor, and the cross section of the conductive portion of the conductor 2 is a profiled structure, oval structure, or wavy structure. The protective layer 7 is made of PVC. The positioning device 5 and the sealing device 4 are the same as those of the First Embodiment, and are not described in detail herein.

The Third Embodiment

[0096] As shown in FIG. 4, the wire harness includes more than one conductor 2. The ends of some conductors 2 are connected to a terminal 1, and the ends of the other conductors 2 are connected according to a circuit requirement by crimping or welding to form a conductor connection point. The surface of the terminal 1 is plated with one selected from the group of silver, nickel, cadmium, zirconium, chromium, cobalt, manganese, aluminum, tin, titanium, zinc, and gold. After the conductors 2 is connected to the terminal 1, the terminal 1 is fitted in a sheath 6 for mutually inserting with an electrical device, and different terminals 1 correspond to different holes of the sheath 6 according to design requirements. At the time of preparation, the conductor connection point is entirely sealed by a wire harness protection device 8, which is a rubber member or a plastic member processed by injection molding. As shown in FIG. 3D, an insulation layer 3 is disposed outside the conductors 2, and a protective layer 7 is injection molded outside the insulation layer 3. The terminal 1 and the sheath 6 in this embodiment are the same as those in the First Embodiment, and are not described in detail herein.

[0097] After the multiple conductors 2 are cut respectively by a predetermined length, according to a design requirement, some conductors 2 are connected to the terminals 1 by crimping or welding, respectively. When the other conductors 2 are two or more conductors and belong to the same circuit, the conductors on a non-terminal side are connected to form a conductor connection point by crimping or welding according to the requirement of the circuit, so as to obtain a semi-finished product. The semi-finished product is then put into an injection mold, and according to the predetermined dimensions, the protective layer 7 is injection molded firstly, then the wire harness protection device 8 is injection molded, and finally the positioning device 5 and/or the sealing device 4 is injection molded according to the injection molding steps described in the Second Embodiment. In this embodiment, the conductor 2 includes multiple strands of wire, and the cross section of the conductive portion of the conductor 2 is a polygonal structure. The material of the wire harness protection device 8 is plastic, and in other applications, the material of the wire harness protection device 8 may be rubber. The protective layer 7, the positioning device 5, and the sealing device 4 in this embodiment are the same as those of the Second Embodiment, and are not described in detail herein.

[0098] In the method of preparing the wire harness by injection molding, when the semi-finished wire harness is provided with a sheath 6, the terminal 1 connected to the conductor 2 is inserted into the corresponding hole of the sheath 6, and then injection molding is performed; or the semi-finished wire harness is injection molded firstly, and then the terminal 1 connected to the conductor 2 is inserted into the corresponding hole of the sheath 6.

[0099] As shown in FIG. 11, when the sheath 6 is in wet areas, in order to prevent water from entering into the sheath 6, the sealing device 4 is provided to seal the holes of the sheath 6, and a waterproof device 9 is injection molded in the gaps between the sheath 6 and the conductors 2 to seal the sheath 6 for waterproof, and a second fixing device 10 is connected at the ends of the waterproof device 9 and the sheath 6. The waterproof device 9 is formed by injection molding, and the second fixing device 10 is a sleeve structure for matching with the protective layer 7 outside the conductors 2.

[0100] As shown in FIG. 12, the sheath 6 described in this embodiment may also be integrally injection molded. The semi-finished wire harness is put into an injection mold, and the sheath 6 is integrally injection molded onto at least the terminal 1. In other embodiments, the sheath 6 may also be integrally injection molded onto the terminal 1 and the conductor 2, or the sheath 6 may be integrally injection molded onto the terminal 1, the conductor 2 and the protective layer 7.

[0101] In order to demonstrate the influences of the wire harness processed by the conventional method and the integrally injection molded wire harness according to the First, Second, and Third Embodiments of the present disclosure on the mechanical properties and electrical properties of the terminal and conductor of the wire harness, the inventor of the present application has conducted a series of experiments on mechanical properties, electrical properties and service life of the two kinds of wire harnesses processed by the above two different methods.

[0102] The specific experimental process is as follows: the actual use environment of the harness is simulated, but the test conditions are increased to a level much stricter than those of the actual use environment, so as to obtain the test results in a short time, which can be achieved for a long time under the actual use environment. The series of experiments include: 1) testing the initial pullout force and voltage drop of the terminal 1 and the conductor 2 of the two kinds of wire harnesses obtained by the above two different methods to obtain the initial mechanical and electrical properties of the wire harnesses; 2) carrying out a salt spray experiment for 1000 hours, by spraying salt water onto the two kinds of wire harnesses using a salt spray experimental box, which can replace the salt spray resistance test for ten years in the actual coastal environment; 3) carrying out a high and low temperature experiment for 200 hours, by putting the two kinds of wire harnesses under the highest and lowest temperatures of the use environment for one hour respectively, with a temperature switching time of less than 5 seconds, and the temperature switching is performed for 100 cycles, which can replace the high and low temperature resistance test for 10 years in the external cold-hot alternate environment; 4) carrying out a vibration test for 120 hours, by fixing the two kinds of wire harnesses on a vibration experiment table, selecting a vibration amplitude according to the use environment, and vibrating the two kinds of wire harnesses in three directions, which can replace the vibration test for 10 years in the actual vibration environment; 5) carrying out an aging test for 6,000 hours, by putting the two kinds of wire harnesses into an aging experiment box to simulate an environment exceeding the rated use conditions, which can replace the aging test for 20 years in the actual use environment. The voltage drop value and the pullout force value of the terminal 1 and the conductor 2 of the two kinds of wire harnesses are tested after each experiment. The experimental results are shown in Tables 1-1, 1-2 and 1-3.

TABLE-US-00001 TABLE 1-1 Influence of the conventional wire harness and the integrally injection molded wire harness on the pullout force and the voltage drop of the terminal and the conductor (before experiment and after the salt spray test for 1000 hours) Type of wire harness Conventional Integrally injection Conventional Integrally injection wire harness molded wire harness wire harness molded wire harness State After the processing is completed After 1,000 hours of salt spray experiment Pullout Voltage Pullout Voltage Pullout Voltage Pullout Voltage force drop force drop force drop force drop Test (N) (mV) (N) (mV) (N) (mV) (N) (mV) 1 2343 0.35 2456 0.34 2057 0.42 2388 0.37 2 2567 0.37 2547 0.35 2136 0.46 2436 0.37 3 2476 0.37 2458 0.36 2085 0.45 2384 0.38 4 2541 0.38 2572 0.35 2064 0.45 2492 0.36 5 2347 0.37 2438 0.36 2088 0.43 2397 0.38 6 2463 0.39 2589 0.35 2126 0.46 2416 0.37 7 2389 0.37 2548 0.34 2063 0.45 2404 0.36 8 2554 0.34 2490 0.33 2081 0.43 2426 0.35 9 2487 0.38 2561 0.32 2066 0.45 2484 0.38 10 2454 0.36 2548 0.33 2083 0.46 2438 0.35 Average 2462.1 0.368 2520.7 0.343 2084.9 0.446 2426.5 0.367 value

TABLE-US-00002 TABLE 1-2 Influence of the conventional wire harness and the integrally injection molded wire harness on the pullout force and the voltage drop of the terminal and the conductor (200 hours of high and low temperature experiment and 120 hours of vibration experiment) Type of wire harness Conventional Integrally injection Conventional Integrally injection wire harness molded wire harness wire harness molded wire harness State After 200 hours of high and low temp, experiment After 20 hours of vibration experiment Pullout Voltage Pullout Voltage Pullout Voltage Pullout Voltage force drop force drop force drop force drop Test (N) (mV) (N) (mV) (N) (mV) (N) (mV) 1 2046 0.43 2373 0.38 2072 0.42 2385 0.36 2 2074 0.45 2426 0.37 2045 0.43 2433 0.36 3 2125 0.44 2387 0.36 2131 0.45 2369 0.37 4 2052 0.46 2448 0.37 2077 0.44 2435 0.37 5 2077 0.43 2372 0.38 2094 0.45 2364 0.38 6 2054 0.45 2435 0.37 2048 0.44 2466 0.37 7 2098 0.46 2416 0.36 2093 0.44 2425 0.38 8 2125 0.45 2462 0.39 2084 0.46 2432 0.36 9 2058 0.43 2469 0.37 2038 0.44 2479 0.36 10 2064 0.44 2415 0.37 2047 0.47 2447 0.38 Average 2077.3 0.444 2420.3 0.372 2072.9 0.444 2423.5 0.369 value

TABLE-US-00003 TABLE 1-3 Influence of the conventional wire harness and the integrally injection molded wire harness on the pullout force and the voltage drop of the terminal and the conductor (600 hours of aging experiment) Type of wire harness Conventional Integrally injection wire harness molded wire harness State After 600 hours of aging experiment Pullout Voltage Pullout Voltage force drop force drop Test (N) (mV) (N) (mV) 1 2064 0.48 2345 0.38 2 2037 0.47 2443 0.37 3 2024 0.47 2354 0.37 4 2034 0.48 2447 0.36 5 2072 0.46 2358 0.38 6 2047 0.48 2349 0.37 7 2052 0.47 2432 0.37 8 2034 0.47 2438 0.36 9 2036 0.48 2475 0.38 10 2049 0.47 2449 0.36 Average value 2044.9 0.473 2409 0.37

[0103] As can be seen from the results of the above Tables 1-1, 1-2 and 1-3, the values of the initial pullout force values and the voltage drop values of the terminal 1 and the conductor 2 of the wire harness processed by the conventional method, are close to those of the wire harness processed by the integrally injection molded method.

[0104] After being subjected to 1,000 hours of salt spray experiment, 200 hours of high and low temperature experiment, 120 hours of vibration experiment, and 6,000 hours aging experiment, respectively, the pullout force values of the terminal 1 and the conductor 2 of the integrally injection molded wire harness are much higher than those of the terminal 1 and the conductor 2 of the wire harness processed by the conventional method, and are also close to the initial pullout force values.

[0105] However, in the wire harness processed by the conventional method, the pullout force of the terminal 1 and the conductor 2 after the experiments is obviously reduced, the mechanical property is unstable, the terminal 1 and the conductor 2 of the wire harness may be disconnected, resulting in a short circuit of the wire harness, which may lead to functional failure in a gentle case and a burning accident in a serious case.

[0106] The voltage drop of the terminal 1 and the conductor 2 of the integrally injection molded wire harness after the experiments is basically the same as the initial voltage drop of the terminal 1 and the conductor 2 of the wire harness processed by the conventional method.

[0107] However, in the wire harness processed by the conventional method, the voltage drop of the terminal 1 and the conductor 2 is obviously reduced, the electrical performance is unstable, and the contact resistance between the terminal 1 and the conductor 2 is increased, which causes the terminal 1 and the conductor 2 of the wire harness to generate heat and turn red when in electric conduction, and in severe cases, the terminal 1 and the conductor 2 will burn due to excessive temperature, resulting in serious accidents.

[0108] Therefore, the mechanical and electrical properties of the integrally injection molded wire harness after the experiments are much better than those of the wire harness processed by the conventional method, thereby reducing the defective rate of the product and prolonging the service life of the wire harness.

[0109] In order to demonstrate the positioning effect of the fixing devices of the wire harnesses processed by the conventional method and by the integrally injection molded method according to the First, Second, and Third Embodiments of the present disclosure under a vibration environment, 100 of the two kinds of wire harnesses are selected respectively, and a vibration test is performed on the fixing devices of the two kinds of wire harnesses. The results are shown in the table below.

TABLE-US-00004 TABLE 2 Influence of the conventional wire harness and the integrally injection molded wire harness on performance of the fixing device through a vibration test (120 hours of vibration experiment) Integrally injection molded wire harness circular ring Conventional wire harness structure or fixing with a fixing with an clip-shaped C-shaped ring tie tape adhesive tape columnar structure structure structure wire wire wire wire wire positioning harness positioning harness positioning harness positioning harness positioning harness size discon- size discon- size discon- size discon- size discon- deviation nection deviation nection deviation nection deviation nection deviation nection 52% 11% 69% 24% 0% 0% 1% 0% 1% 0%

[0110] As can be seen from the above Table, in the conventional wire harness with the positioning device being fixed by a tie tape, the number of the wire harnesses with positioning size deviation of the positioning device 5 accounts for 52% of the total number of the wire harnesses, and the number of the wire harnesses disconnected accounts for 11% of the total number of the wire harnesses, with a very high defective rate. In the conventional wire harness with the positioning device 5 being fixed by an adhesive tape, the number of the wire harnesses with positioning size deviation of the positioning device 5 accounts for 69% of the total number of the wire harnesses, and the number of the wire harnesses disconnected accounts for 24% of the total number of the wire harnesses, with a very high defective rate. The high defective rate seriously affects the installation and function of the wire harness, and may cause function failure of the wire harness in severe cases.

[0111] However, for three kinds of positioning devices 5 of the integrally injection molded wire harness, the number of the wire harnesses with positioning size deviation of the positioning device 5 accounts for only 0%, 1% and 1% of the total number of the wire harnesses respectively, and the number of the wire harnesses disconnected accounts for 0% of the total number of the wire harnesses. Therefore, in the integrally injection molded wire harness, the positioning device 5 is more firmly combined with the wire harness, the positioning device 5 is not easy to fall off, and the positioning effect is better. Even in a relatively harsh vibration environment, the positioning function failure of the wire harness caused by the positioning size deviation of the positioning device 5 or the disconnection of the wire harness rarely occurs, which can significantly prolong the service life of the wire harness.

[0112] In order to demonstrate the protection levels of the sealing devices 4 in the wire harness processed by the conventional method and in the integrally injection molded wire harness according to the First, Second, and Third Embodiments of the present disclosure against external dust and water attack, 100 of the two kinds of wire harnesses are selected respectively, and the protection level of the sealing devices 4 of the two kinds of wire harnesses are tested. The results are shown in the table below.

TABLE-US-00005 TABLE 3 The passing ratios of protection level of the sealing devices in the conventional wire harness and the integrally injection molded wire harness Conventional wire harness Integrally injection molded wire harness Sealing of Sealing of Sealing of Sealing of via hole on terminal and Sealing of via hole on terminal and Sealing of partition plate conductor sheath partition plate conductor sheath IP54 IP67 IP54 IP67 IP54 IP67 IP54 IP67 IP54 IP67 IP54 IP67 89% 68% 92% 75% 88% 71% 100% 99% 100% 100% 100% 100%

[0113] As can be seen from the above Table, in the protection level test of IP54, the passing ratios of three kinds of sealing devices 4 in the conventional wire harness are only 89%, 92% and 88% respectively, and in the protection level test of IP67, the passing ratios are only 68%, 75% and 71% respectively, thus the low passing ratios of the protection level makes it impossible to ensure the sealing performance of the wire harness or to prevent the corrosion of the conductor 2 by dust and water from the external environment, which will causes function failure of the wire harness.

[0114] In the protection level test of IP54, the passing ratios of three kinds of sealing devices 4 of the integrally injection molded wire harness are totally 100%, and in the protection level test of IP67, the passing ratios are 99%, 100% and 100% respectively, which fully satisfy the sealing performance requirement of the wire harness, make the sealing performance of the wire harness better, prevent dust and water in the external environment from corroding the conductor, and remarkably improve the service life of the wire harness.

[0115] In order to demonstrate the influence of wrapping the conductor connection points in different ways on the risk of breakage of the conductor connection points of the wire harness processed by the conventional method and the integrally injection molded wire harness according to the First, Second, and Third Embodiments of the present disclosure, 100 of the two kinds of wire harnesses are selected respectively, then a 120 hours of vibration experiment is performed on the two kinds of wire harnesses respectively, and then the breakage ratios of the conductor connection points are measured. The results are shown in the table below.

TABLE-US-00006 TABLE 4 The breakage ratios of the conductor connection points of conventional wire harness and the integrally injection-molded wire harness Integrally injection Conventional wire harness molded wire harness Conductor connection Conductor connection Conductor connection points are wrapped points are wrapped points are wrapped with an adhesive tape with a heat shrink tubing by injection-molding 26% 18% 0%

[0116] As can be seen from the above Table that there are two ways of wrapping the conductor connection point of the conventional wire harness. After the wire harnesses are subjected to the 120 hours of vibration experiment, the breakage ratio of the conductor connection points wrapped with an adhesive tape is 26%, and the breakage ratio of the conductor connection points wrapped with a heat shrink tubing is 18%. This shows that the breakage ratio of the conductor connection points is high, which cannot guarantee the electrical conductivity of the wire harness in harsh vibration environment, resulting in a great risk of function failure of the wire harness.

[0117] However, the breakage ratio of the conductor connection points wrapped by injection molding of the injection molded wire harness is 0%, which can completely meet the conduction performance requirement of the wire harness in the harsh vibration environment, and remarkably improve the service life of the wire harness.

[0118] The above embodiments are only exemplary embodiments of the present disclosure, and the scope of protection of the present disclosure is not limited thereto. Any non-essential changes and substitutions made by those skilled in the art on the basis of the present disclosure are within the scope of the claimed invention.