Manufacturing method of large-diameter space electromagnetic shielding effect test wire harness

Abstract

The invention belongs to an aircraft wire harness manufacturing technology, and relates to a manufacturing method of a large-diameter space electromagnetic shielding effect test wire harness. According to the needed layout, a polyethylene hose with the cable diameter consistent with that of a simulation part is selected to replace a wire harness needing to be tested, bifurcation is achieved through a fusion method, a silica gel self-adhesive tape is used at a bifurcation connector for fixing and transition, and a large-diameter space simulation wire harness is formed; by adopting a common polytetrafluoroethylene material end connection method, different wire harness specifications and shapes can be realized, a space wire harness model is formed, a sensor is simple and convenient to install and fix, analogue simulation of a large-diameter wire harness is realized, and a space electromagnetic shielding effect test can be realized.

Description

Technical Field

[0001] The invention belongs to aircraft harness manufacturing technology and relates to a method for manufacturing a large-diameter space electromagnetic shielding effect test harness. Background Art

[0002] In order to meet the ability to measure the spatial electromagnetic shielding effect of large-diameter cables in a laboratory environment, it is necessary to simulate the large-diameter cables specifically for the test environment. If the simulation is directly performed using real wires, a special test harness needs to be designed because the metal wires will affect the distribution and numerical testing of the electromagnetic effect. Summary of the invention

[0003] The objects of the present invention are:

[0004] The purpose of the present invention is to provide a special test cable specially designed for simulating and testing the electromagnetic shielding effect of a large diameter space, which can not only meet the test of the space shielding effect, but also has no influence on the test result.

[0005] The technical solution of the present invention is: a method for manufacturing a large-diameter space electromagnetic shielding effect test harness, comprising the following steps:

[0006] Step 1: Layout of the wiring harness: According to the required layout, a polyethylene hose with the same cable diameter as the simulated part is selected to replace the wiring harness to be tested, and the bifurcation is achieved by fusion. Silicone self-adhesive tape is used to fix and transition at the bifurcation interface to form a large-diameter space simulation wiring harness;

[0007] Step 2: Perform electromagnetic shielding treatment on the wire harness outside the large-diameter space simulation wire harness to form a large-diameter space simulation shielded wire harness;

[0008] Step 3: Select a coaxial cable with the same length as the test harness as the sensor cable. Reserve a shield layer at each end of the sensor cable and remove the shield layer in the middle.

[0009] Step 4: The sensor cable passes through a large diameter space to simulate a shielded harness with several branches passing through several sensor cables;

[0010] Step 5: Use copper foil to wrap the end of the shielded wire harness in a large diameter space.

[0011] Step 6: Place the end guards on both ends of the sensor test cable.

[0012] The fusion method in step 1 is as follows: the bifurcation of the polyethylene hose main bundle pipe is mechanically processed to form a branch opening, and the polyethylene hose branch pipe is fixed at the branch opening by a hot-melt clamp and fused by heating.

[0013] The hot melt clamp includes a branch pipe clamp 16, a main pipe clamp 17, and a tightening force rod 18; the polyethylene hose branch pipe is embedded in the branch pipe clamp 16 of the hot melt clamp, and the polyethylene hose main pipe is embedded in the main pipe clamp 17 of the hot melt clamp. The branch pipe clamp 16 and the main pipe clamp 18 are connected, and the force rod 18 is tightened.

[0014] How to use the hot melt clamp: embed the polyethylene hose branch pipe into the branch pipe clamp 16 of the hot melt clamp, and embed the polyethylene hose main bundle pipe into the main bundle pipe clamp 17 of the hot melt clamp. Use a hot melt tool to heat the connection part. After reaching the connection temperature, quickly connect the branch pipe clamp 16 and the main bundle pipe clamp 17, tighten the force rod 18, and connect the heated polyethylene hose until the connection part cools and solidifies.

[0015] The electromagnetic shielding processing method includes: inserting an electromagnetic shielding heat shrink tube into a large-diameter space simulation wiring harness, and then using a hot air gun to continuously heat the electromagnetic shielding heat shrink tube for 2 minutes at a temperature of 110° C.-130° C., so that the electromagnetic shielding heat shrink tube fits tightly to the large-diameter space simulation wiring harness.

[0016] After the electromagnetic shielding treatment is completed, the resistance at both ends of the internal shielding layer after the shield connection is no more than 1 ohm

[0017] In step 3, the reserved shielding layer length at both ends of the sensor cable is 20 mm.

[0018] The sensor cable end is protected by a plastic sheath.

[0019] The advantages of the present invention are:

[0020] The present invention adopts a terminal connection method that does not require complicated equipment and processes and uses commonly used polytetrafluoroethylene materials to achieve different wire harness specifications and shapes to form a space wire harness model. The installation and fixation of the sensor is simple and convenient, and the simulation of large-diameter wire harnesses can be achieved, which can realize the test of space electromagnetic shielding effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Typical process steps;

[0022] Among them: 1-large diameter space simulation shielded wire harness, 2-sensor cable a, 3-sensor cable b, 10 is hot melt clamp

[0023] Figure 2 Single harness process manufacturing method;

[0024] Among them: 4-single harness large diameter space simulation shielded harness 5-sensor cable.c

[0025] Figure 3 Multi-branch wiring harness manufacturing method;

[0026] Among them: 6-multi-branched large-diameter space simulation shielded wire harness, 7-sensor cable d, 8-sensor cable e, 9-sensor cable f.

[0027] Figure 4 Three-way multi-branch large diameter space simulation shielded wire harness;

[0028] Including: 11-polyethylene hose b

[0029] Figure 5 Hot melt clamp.

[0030] Among them: 16-branch pipe clamp 17-main bundle pipe clamp 18-force rod DETAILED DESCRIPTION

[0031] In order to make the purpose and advantages of the present invention more clearly understood, the present invention is specifically described below in conjunction with the embodiments. The following text is only used to describe one or several specific implementations of the present invention, and does not strictly limit the protection scope of the specific claims of the present invention.

[0032] A method for manufacturing a large-diameter space electromagnetic shielding effect test harness comprises the following steps:

[0033] Step 1: Layout of the wiring harness: According to the required layout, a polyethylene hose with the same cable diameter as the simulated part is selected to replace the wiring harness to be tested, and the bifurcation is achieved by fusion. Silicone self-adhesive tape is used to fix and transition at the bifurcation interface to form a large-diameter space simulation wiring harness;

[0034] The fusion method is as follows: mechanically process the bifurcation of the polyethylene hose main bundle pipe to form a branch opening, fix the polyethylene hose branch pipe at the branch opening by a hot melt clamp to ensure reliable connection of the bifurcation point, embed the polyethylene hose branch pipe into the branch pipe clamp 16 of the hot melt clamp 10, and embed the polyethylene hose main bundle pipe into the main bundle pipe clamp 17 of the hot melt clamp, remove impurities and oil stains from the polyethylene hose at the connection part, use a hot melt tool to heat the connection part, quickly dock the branch pipe clamp 16 and the main bundle pipe clamp 17 after reaching the connection temperature, tighten the force rod 18, and connect the heated polyethylene hose until the connection part cools and solidifies.

[0035] Step 2: Perform electromagnetic shielding treatment on the wire harness outside the large-diameter space simulation wire harness to form a large-diameter space simulation shielded wire harness;

[0036] Electromagnetic shielding treatment method: Use electromagnetic shielding heat shrink tube to put it into the large-diameter space simulation wire harness, and then use a hot air gun to heat the electromagnetic shielding heat shrink tube for 2 minutes at a temperature of 110℃-130℃, so that the electromagnetic shielding heat shrink tube fits tightly to the large-diameter space simulation wire harness.

[0037] After the electromagnetic shielding treatment is completed, the resistance at both ends of the internal shielding layer after the shield connection is no more than 1 ohm

[0038] Step 3: A coaxial cable with the same length as the test harness is selected as the sensor cable. A shielding layer is reserved at each end of the sensor cable, and the shielding layer in the middle is removed. The length of the shielding layer reserved at both ends of the sensor cable is 20 mm.

[0039] Step 4: The sensor cable passes through a large diameter space to simulate a shielded harness with several branches passing through several sensor cables;

[0040] Step 5: Use copper foil to wrap the end of the shielded wire harness in a large diameter space.

[0041] Step 6: Place the sensor cable end guards on both ends of the sensor test cable.

[0042] The sensor cable end is protected by a plastic sheath, which must match the sensor test cable to provide better mechanical protection and prevent the end from being squeezed by external forces.

[0043] For analog wiring harnesses with large differences between the end and the sensor cable, multiple transitions are used to achieve connection matching.

[0044] Example 1

[0045] like Figure 2 As shown, the single harness manufacturing method has the following steps: Figure 2 Including step 1: Layout of the harness: According to the single harness layout, a polyethylene hose with the same cable diameter as the simulated part is selected to replace the harness to be tested, forming a large-diameter single harness space simulation harness; step 2: electromagnetic shielding of the harness is performed outside the large-diameter space simulation harness to form a large-diameter single harness space simulation shielded harness 4; step 3: a sensor cable c5 is selected, and a 20mm shielding layer is reserved at both ends of the sensor cable, and the middle shielding layer is removed. Step 4: The sensor cable c5 passes through the large-diameter space simulation shielded harness 4; step 5: copper foil is used to wrap the end of the large-diameter space simulation shielded harness 4. Step 6: The end protection is placed at both ends of the sensor cable c5 to form a single-beam large-diameter space electromagnetic shielding effect test harness.

[0046] Example 2

[0047] like Figure 3As shown, a multi-branch harness manufacturing process method, the specific process is step 1: harness layout: according to the required three-branch layout, a polyethylene hose with a cable diameter consistent with the simulation part is selected to replace the harness to be tested, and a silicone self-adhesive tape is used at the fork interface for fixing and transition to form a large-diameter space simulation harness; step 2: the harness is electromagnetically shielded outside the large-diameter space simulation harness to form a large-diameter space simulation shielded harness 6; step 3: the sensor cable selects 3 coaxial cables with the same length as the test harness as sensor cables 7, sensor cables 8, and sensor cables 9, and a 20mm shielding layer is reserved at both ends of the sensor cable, and the middle shielding layer is removed. Step 4: the sensor cable passes through the large-diameter space simulation shielded harness, which has three branches and passes through three sensor cables; step 5: copper foil is used to wrap the end of the three-branch large-diameter space simulation shielded harness 6. Step 6: the end protection is placed at both ends of the sensor test cable.

[0048] Example 3

[0049] like Figure 1 As shown, the single bifurcated wiring harness manufacturing method comprises the following steps: Figure 1 Including step 1: Layout of the harness: According to the single bifurcated harness layout, a polyethylene hose with the same cable diameter as the simulated part is selected to replace the harness to be tested. Step 2: Mechanically process the bifurcation to form a connection interface, and use the interface fixing device to bifurcate the connection. Step 3: Use a hot air gun to heat-melt the interface, and after cooling, a large-diameter single-harness space simulation harness is formed; Step 4: Perform electromagnetic shielding treatment on the harness outside the large-diameter space simulation harness to form a large-diameter single-harness space simulation shielded harness 4; Step 5: Select a sensor cable c5, reserve 20mm shielding layer at both ends of the sensor cable, and remove the middle shielding layer. Step 4: The sensor cable c5 passes through the large-diameter space simulation shielded harness 4; Step 6 Use copper foil to wrap the end of the large-diameter space simulation shielded harness 4. Step 7: Place the end protection at both ends of the sensor cable c5 to form a single-harness large-diameter space electromagnetic shielding effect test harness.

[0050] Example 4

[0051] like Figure 4 As shown, the single bifurcated wiring harness manufacturing method comprises the following steps: Figure 4Including step 1: Layout of the harness: According to the single bifurcated harness layout, a polyethylene hose with a cable diameter consistent with the simulated part is selected to replace the harness to be tested. Step 2 Select a polyethylene three-way connector 11 consistent with the requirements at the bifurcation. Step 3: Insert a matching polyethylene hose on the branch formed by it to form a large-diameter single-harness space simulation harness; Step 4: Perform electromagnetic shielding treatment on the harness outside the large-diameter space simulation harness to form a large-diameter single-harness space simulation shielded harness 4; Step 5: Select a sensor cable c5, reserve a 20mm shielding layer at both ends of the sensor cable, and remove the middle shielding layer. Step 6: The sensor cable c5 passes through the large-diameter space simulation shielded harness 4; Step 7 Use copper foil to wrap the end of the large-diameter space simulation shielded harness 4. Step 8: Place the end protection at both ends of the sensor cable c5 to form a single-harness large-diameter space electromagnetic shielding effect test harness.

[0052] The above is only a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principles of the present invention, and these improvements and modifications should also be considered as the protection scope of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention shall be implemented according to the conventional means in the art unless otherwise specified and limited.

Claims

1. A method for manufacturing a large-diameter space electromagnetic shielding effect test harness, characterized in that: The following steps are involved: Step 1: Layout of the wiring harness: According to the required layout, a polyethylene hose with the same cable diameter as the simulated part is selected to replace the wiring harness to be tested, and the bifurcation is achieved by fusion. Silicone self-adhesive tape is used to fix and transition at the bifurcation interface to form a large-diameter space simulation wiring harness; Step 2: Perform electromagnetic shielding treatment on the wire harness outside the large-diameter space simulation wire harness to form a large-diameter space simulation shielded wire harness; Step 3: Select a coaxial cable with the same length as the test harness as the sensor cable. Reserve a shield layer at each end of the sensor cable and remove the shield layer in the middle. Step 4: The sensor cable passes through a large diameter space to simulate a shielded harness with several branches passing through several sensor cables; Step 5: Use copper foil to wrap the end of the shielded wire harness in a large diameter space. Step 6: Place the end guards on both ends of the sensor test cable.

2. The method for manufacturing a large-diameter space electromagnetic shielding effect test harness according to claim 1, characterized in that: The fusion method in step 1 is as follows: the bifurcation of the polyethylene hose main bundle pipe is mechanically processed to form a branch opening, and the polyethylene hose branch pipe is fixed at the branch opening by a hot-melt clamp and fused by heating.

3. The method for manufacturing a large-diameter space electromagnetic shielding effect test harness according to claim 2, characterized in that: The hot melt clamp comprises a branch pipe clamp (16), a main pipe clamp (17), and a tightening force rod (18); the polyethylene hose branch pipe is embedded in the branch pipe clamp (16) of the hot melt clamp, the polyethylene hose main pipe is embedded in the main pipe clamp (17) of the hot melt clamp, the branch pipe clamp (16) and the main pipe clamp (18) are butt-jointed, and the force rod (18) is tightened.

4. The method for manufacturing a large-diameter space electromagnetic shielding effect test harness according to claim 3, characterized in that: Method for using the hot melt clamp: embed the polyethylene hose branch pipe into the branch pipe clamp (16) of the hot melt clamp, embed the polyethylene hose main bundle pipe into the main bundle pipe clamp (17) of the hot melt clamp, use a hot melt tool to heat the connection part, and quickly connect the branch pipe clamp (16) and the main bundle pipe clamp (17) after reaching the connection temperature, tighten the force rod (18), and connect the heated polyethylene hose until the connection part cools and solidifies.

5. The method for manufacturing a large-diameter space electromagnetic shielding effect test harness according to claim 1, characterized in that: Electromagnetic shielding treatment method: Use electromagnetic shielding heat shrink tube to put it into the large-diameter space simulation wire harness, and then use a hot air gun to heat the electromagnetic shielding heat shrink tube for 2 minutes at a temperature of 110℃-130℃, so that the electromagnetic shielding heat shrink tube fits tightly to the large-diameter space simulation wire harness.

6. The method for manufacturing a large-diameter space electromagnetic shielding effect test harness according to claim 1, characterized in that: After the electromagnetic shielding process is completed, the resistance at both ends of the internal shielding layer after the shield connection is no more than 1 ohm.

7. The method for manufacturing a large-diameter space electromagnetic shielding effect test harness according to claim 1, characterized in that: In step 3, the reserved shielding layer length at both ends of the sensor cable is 20 mm.

8. The method for manufacturing a large-diameter space electromagnetic shielding effect test harness according to claim 1, characterized in that: The sensor cable end is protected by a plastic sheath.

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