Electromagnetic driving hole guiding method and device for aircraft blind area structure

Abstract

The invention belongs to the field of aircraft assembly and maintenance, and relates to an electromagnetic drive hole guiding method and device for an aircraft blind area structure. According to the method, alternating bias voltage is used for acting on an electromagnet to generate an alternating magnetic field, so that an impact assembly containing a permanent magnet vibrates at high frequency, the vibration energy is small and controllable, punching marks are left on outer-layer parts, the method is suitable for composite materials, aluminum alloy and the like, and accurate and rapid hole guiding of connecting hole positions of the inner-layer parts of a closed structure assembly is achieved. The guide sleeve and the vibration impact assembly are fast to install, attract each other and are suitable for hole guiding in different postures, the permanent magnet on the vibration impact assembly can attract the guide piece, additional fixing is not needed, falling is avoided, and the device is suitable for efficient hole guiding in large-scale arrangement.

Description

Technical Field

[0001] The invention belongs to the field of aircraft assembly and maintenance, and relates to an electromagnetically driven hole-guiding method and device for an aircraft blind area structure. Background Art

[0002] In the process of aircraft assembly, more and more composite skin structures are used. The internal structure is very compact. When drilling holes in the external skin and frames, long spars, and ribs, there are many cases where the internal frames, long spars, and ribs are invisible and inaccessible. The width of the frames, long spars, and ribs is limited, and the hole position and hole margin accuracy are required to be very high. Therefore, it is difficult to ensure the accuracy of the connection holes on the frames, long spars, and ribs. In the process of repairing and replacing parts, it is also necessary to lead the holes on the structure to the new parts. The traditional punching method is not suitable for composite material hole leading, and the punching error is large for areas with large curvature.

[0003] In order to solve the above problems, a method is invented based on electromagnetic effect, which uses electromagnet to apply voltage of special waveform to drive the hole-guiding device to vibrate periodically, so as to guide the center of the guide hole on the inner blind area part to the outer part. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides an electromagnetically driven hole-drawing method and device for an aircraft blind area structure.

[0005] The technical solution of the present invention is as follows:

[0006] The electromagnetic driven hole-drawing method for the blind spot structure of aircraft uses a biased alternating voltage to make the electromagnet generate an alternating electromagnetic field. A special hole-drawing mechanism is installed on the inner side of the guide hole of the inner layer part. The hole-drawing mechanism contains a permanent magnet. The electromagnet is placed on the outer side of the outer layer part, and generates periodic attraction and repulsion with the permanent magnet on the inner side of the inner layer part, driving the hole-drawing tool to produce punch marks or traces on the outer layer part. The specific steps are:

[0007] Step 1: Power Waveform Selection

[0008] Choose a power supply with AC and DC series connection function, adjustable voltage and frequency; you can also choose a program-controlled power supply with a custom voltage waveform setting function. The final working voltage waveform is a biased sine wave or square wave, such as Figure 1 As shown, V is voltage, t is time, and Δ is DC bias voltage. The effect of this bias DC voltage is that within one AC cycle, the alternating magnetic field generated by the current in the electromagnet is asymmetric, and the maximum attraction to the permanent magnet is greater than the maximum repulsion. It can be simply understood that the magnetic field generated by the DC voltage produces an attraction to the permanent magnet, and the AC current produces periodic attraction and repulsion, and the peak voltage of the AC current is higher than the DC voltage.

[0009] Step 2: Select the Electromagnet

[0010] Select an alternating current electromagnet with a core made of silicon steel to reduce eddy current heating. The function of the electromagnet is to generate an electromagnetic field that constantly exchanges magnetic poles, causing the permanent magnet used for the hole to vibrate.

[0011] Step 3: Design the hole guide

[0012] The hole-guiding mechanism includes two components: a guide member and a vibration component. The guide member is a bushing structure made of carbon steel and can be attracted by a magnet. The outer circle of the guide member is inserted into the guide hole of the inner part. The guide member includes a boss, which is sandwiched between the inner and outer parts so as to be stably fixed. The vibration component is inserted into the guide hole and can vibrate in the guide under the action of the alternating magnetic field of the electromagnet. The vibration component includes a permanent magnet and a punch needle, which are fixedly connected. The punch needle is inserted into the guide hole and has a sharp point. When vibrating, a punch mark can be generated on the outer part. The punch mark is the center of the hole position of the inner part. Before the electromagnet works, the permanent magnet on the vibration component and the guide member attract each other to prevent the hole-guiding device from slipping out of the guide hole.

[0013] Step 4: Make Guide Holes

[0014] Before the outer layer parts are installed, a guide hole is first made on the inner layer parts. The diameter of the guide hole is smaller than the final hole diameter, and its hole diameter is consistent with the outer diameter of the guide part.

[0015] Step 5: Guide Installation

[0016] A guide piece is installed in the guide hole of the inner layer part, the outer diameter of the guide piece is consistent with the hole diameter of the inner part guide hole, and the inner hole diameter is consistent with the punching needle diameter of the hole guiding device.

[0017] Step 6: Outer Parts Installation

[0018] Install the vibration assembly inside the inner part and in the hole of the guide part, and then install the outer part to the outside of the inner part.

[0019] Step 7: Determine the electromagnet installation position

[0020] Use a lightweight and powerful permanent magnet to move on the outer part. Because there is a permanent magnet on the vibration device at the guide hole position of the inner part, the lightweight and compact permanent magnet will be adsorbed to the surface of the outer part. This position is the position of the permanent magnet on the vibration device, that is, the rough position of the guide hole of the inner part. Mark this position with a marker. The powerful permanent magnet is selected in a circular shape, and its inner circle can be easily marked with a marker.

[0021] Step 8: Electromagnet Working

[0022] Connect the electromagnet to the power supply selected in step 1, where the magnetic field generated by the DC power supply is consistent with the magnetic field direction of the permanent magnet on the vibration mechanism, that is, within one AC cycle, the attraction is greater than the repulsion, and place the electromagnet at the marked position in step 7.

[0023] Step 9: Power Supply Regulation

[0024] Adjust the AC voltage, frequency and DC voltage of the power supply, where the DC voltage is not greater than 2 / 3 of the AC voltage peak. Finally, adjust it to the point where the vibration mechanism produces stable vibration with an intensity sufficient for the working rod to produce punch marks on the outer parts. Record the adjusted AC voltage, frequency and DC voltage, and use this voltage and frequency directly when drilling holes later.

[0025] Step 10: Find the location of the punch mark or trace

[0026] When the outer layer parts are removed and the punch marks are difficult to find, place a permanent magnet at the marked position on the outside of the outer layer parts in step 7, and use the lightweight and compact permanent magnet in step 7 to move the inner side of the outer layer parts. The adsorption position is the rough position of the punch mark or trace position to confirm the punch mark.

[0027] Step 11: Making Holes

[0028] According to the punch mark positions produced in steps 9 and 10, make holes in the outer part, making the holes concentric with the holes in the inner part. Reinstall the outer part, align the holes made in the outer part with the guide holes in the inner part, and expand the holes to the final size.

[0029] Based on the above method, an electromagnetically driven hole-guiding device for a blind area structure is invented. The device includes an electromagnet assembly, a guide, a vibration impact assembly, a power supply, and a small annular magnet.

[0030] The electromagnet assembly is used to provide an alternating electromagnetic field, and includes an electromagnet, a handle, a switch, a cable, and a plug. The electromagnet and the handle are fixed together with bolts, and the plug is inserted into a power source to power the electromagnet.

[0031] The vibration impact assembly is used to vibrate under the action of an alternating electromagnetic field to leave a punch mark on the product. The vibration impact assembly includes a punch needle, a permanent magnet A5-2, a permanent magnet B, and a spring. The annular permanent magnet A and permanent magnet B are nested on both sides of the punch needle head. The permanent magnets A and B attract each other, and adsorb the permanent magnets A, B, and the punch needle as a whole. The spring is sleeved on the working rod of the punch needle and will not detach under the magnetic attraction of the permanent magnet B, assisting the device to generate stable vibration. The working rod of the punch needle is sleeved in the inner hole of the guide part, clamping the spring between the guide part and the punch needle head. The guide part is used to insert into the guide hole of the inner layer part of the product to be processed, and the inner hole of the guide part is coaxial with the guide hole of the inner layer part.

[0032] Beneficial effects of the present invention:

[0033] The method of the present invention is designed to use an alternating bias voltage to act on an electromagnet to generate an alternating magnetic field, so that an impact component containing a permanent magnet vibrates at a high frequency, the vibration energy is small and controllable, and punch marks are left on the outer parts. It is suitable for composite materials, aluminum alloys, etc., and realizes accurate and rapid hole drawing of the connection holes of the inner parts of a closed structure assembly.

[0034] The guide sleeve and vibration impact assembly of the invention are quick to install and attract each other, and are suitable for drilling holes in different postures. The permanent magnet on the vibration impact assembly can attract the guide piece and does not need additional fixation to prevent it from falling off, so it is suitable for large-scale deployment and efficient drilling. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a schematic diagram of a biased sine wave, Δ is the biased DC voltage;

[0036] Figure 2 is a schematic diagram of a biased square sine wave, Δ is the biased DC voltage;

[0037] Figure 3 Axonometric view of electromagnetic driven hole guiding device;

[0038] Figure 4 Axonometric view of the electromagnet assembly;

[0039] Figure 5 Cross-sectional view of the guide and vibration impact assembly in working condition.

[0040] In the figure: 1-inner parts; 2-outer parts; 3-electromagnet assembly; 4-guide; 5-vibration impact assembly; 6-power supply; 7-small annular magnet. 3-1 electromagnet; 3-2 handle; 3-3 switch; 3-4 cable; 3-5 plug; 5-1 punch pin; 5-2 permanent magnet A; 5-3 permanent magnet B; 5-4 spring. DETAILED DESCRIPTION

[0041] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings and technical solutions.

[0042] Step 1: Make guide holes for inner parts

[0043] Before the outer layer part 2 is installed, a plurality of guide holes are made on the inner layer part 1. The diameter of the guide holes is smaller than the final design diameter, and the drilled guide holes are consistent with the outer diameter of the guide member 4.

[0044] Step 2: Install the guide and vibration impact assembly

[0045] Insert several guide members 4 into the guide holes made in step 1 from the front side of the inner layer part 1 , and then insert several vibration impact components 5 into the inner holes of the guide members 4 from the back side of the inner layer part 1 .

[0046] Step 3: Install the outer parts

[0047] Install the outer part 2 to the outside of the inner part 1 and fix it in the theoretical position.

[0048] Step 4: Determine the initial hole position

[0049] Shake the small magnet 7 outside the outer part 2. Its adsorption position is the approximate position of the vibration impact assembly 5 containing the permanent magnet. Use a marker to mark the outer part 2 through the center circle hole of the small magnet 7. Repeat this step to mark all the guide hole positions.

[0050] Step 5: Connect the Electromagnet Assembly and Power Supply

[0051] Insert the plug 3 - 5 of the electromagnet assembly 3 into the power supply 6 and turn on the power transmission switch of the power supply 6 .

[0052] Step 6: Placing the Electromagnet for Vibration

[0053] Place the electromagnet 3 at the position marked in step 4, turn on the switch 3-3, the electromagnet is powered on and starts working, generating an alternating electromagnetic field. The vibration impact assembly 5 vibrates under the action of the alternating electromagnetic field of the electromagnet, and the punch needle 5-1 generates a punch mark on the outer part 2. Adjust the AC voltage, frequency and DC voltage value of the power supply 6 to change the impact force of the punch needle 5-1, and finally ensure that a recognizable punch mark is generated on the part 2. Record the voltage and frequency values, which can be used directly later.

[0054] Step 7: Remove the Outer Parts and Vibration Shock Assembly

[0055] Remove the outer layer part 2, remove the vibration impact assembly 5 from the guide member 4, and then remove the guide member 4 from the inner layer part 1.

[0056] Step 8: Find the punch mark location and make the guide hole

[0057] When the punch mark produced in step 6 on the inner side of the outer part 2 is not obvious, place the vibration impact assembly 5 at the mark of step 4 on the outer side of the outer part 2, fit the permanent magnet 5-2 with the outer part 2, and shake the small magnet 7 on the inner side of the outer part 2. The place attracted by the permanent magnet 5-2 is the approximate position of the punch mark, which makes it easy to find the position of the punch mark. Drill a guide hole on the outer part 2 according to the position of the punch mark, and its diameter is consistent with the diameter of the guide hole of the inner part.

[0058] Step 9: Make the Final Hole

[0059] Repeat step 3 to reinstall the outer layer part 2 on the outside of the inner layer part 1 and fix it, and expand the guide holes made in steps 1 and 8 to the final hole diameter.

Claims

1. An electromagnetically driven hole-guiding method for an aircraft blind area structure, characterized in that: Here are the steps: Step 1: Power Waveform Selection The waveform of the working voltage is a biased sine wave or square wave. The effect of the biased DC voltage is that in one AC cycle, the alternating magnetic field generated by the current in the electromagnet is asymmetric, and the maximum attraction force on the permanent magnet is greater than the maximum repulsion force; Step 2: Select the Electromagnet Step 3: Design the hole guide The hole guiding mechanism comprises two components, namely a guide member (4) and a vibration component. The guide member (4) is a bushing structure. The outer circle of the guide member (4) is inserted into the guide hole of the inner layer component (1). The guide member (4) comprises a boss, which is sandwiched between the inner and outer layer components (2) so as to be stably fixed. The vibration component is inserted into the hole of the guide member (4) and can vibrate in the guide member (4) under the action of the alternating magnetic field of the electromagnet. Step 4: Make Guide Holes Before the outer layer part (2) is installed, a guide hole is first made on the inner layer part (1), the diameter of the guide hole is smaller than the final hole diameter, and the hole diameter is consistent with the outer diameter of the guide part (4); Step 5: Install the guide (4) A guide member (4) is installed in the guide hole of the inner layer part (1), wherein the outer diameter of the guide member (4) is consistent with the hole diameter of the inner part guide hole, and the inner hole diameter is consistent with the punching needle diameter of the hole guiding device; Step 6: Outer Parts (2) Installation Install the vibration assembly inside the inner part (1) and in the hole of the guide member (4), and after the installation, install the outer part (2) on the outer side of the inner part (1); Step 7: Determine the electromagnet installation position Use a permanent magnet to move on the outer part (2). Because there is a permanent magnet on the vibration device at the position of the guide hole of the inner part (1), the permanent magnet will be adsorbed to the surface of the outer part (2). This position is the position of the permanent magnet on the vibration device, that is, the rough position of the guide hole of the inner part (1). Mark this position with a marker. Step 8: Electromagnet Working Connect the electromagnet to the power supply selected in step 1, wherein the magnetic field generated by the direct current of the power supply is consistent with the magnetic field direction of the permanent magnet on the vibration mechanism, that is, in one AC cycle, the attractive force is greater than the repulsive force, and place the electromagnet at the marked position in step 7; Step 9: Power Supply Regulation Adjust the AC voltage, frequency and DC voltage of the power supply, wherein the DC voltage is not greater than 2 / 3 of the AC voltage peak value, and finally adjust the vibration mechanism to produce stable vibration, the intensity of which is sufficient for the working rod to produce a punch mark on the outer part (2), and record the adjusted AC voltage, frequency and DC voltage, and directly use the voltage and frequency when drilling holes later; Step 10: Find the punch mark or trace position When the outer part (2) is removed and the punch mark is difficult to find, a permanent magnet is placed at the marked position on the outside of the outer part (2) in step 7, and the light and compact permanent magnet of step 7 is moved on the inside of the outer part (2). The adsorption position is the rough position of the punch mark or trace position, so as to confirm the punch mark; Step 11: Making Holes According to the punch marks produced in steps 9 and 10 on the outer part (2), a hole is made on the outer part (2), the hole made is concentric with the hole on the inner part (1), the outer part (2) is reinstalled, the hole made on the outer part (2) is aligned with the guide hole on the inner part (1), and the hole is expanded to the final size.

2. The electromagnetically driven hole-guiding method for an aircraft blind area structure according to claim 1, characterized in that: The vibration component of step 3 comprises a permanent magnet and a punching needle, which are fixedly connected to each other. The punching needle is inserted into the hole of the guide member (4) and has a sharp point. When vibrating, a punch mark can be generated on the outer layer part (2). The punch mark is the center of the hole position of the inner layer part (1). Before the electromagnet works, the permanent magnet on the vibration component and the guide member (4) attract each other, which can prevent the hole-guiding device from slipping out of the hole of the guide member (4).

3. The electromagnetic driven hole-guiding method for aircraft blind area structure according to claim 1 or 2, characterized in that: The strong permanent magnet in step 7 is selected to be in a circular shape, and its inner circle can be easily marked with a marker pen.

4. The electromagnetically driven hole-guiding method for an aircraft blind area structure according to claim 1 or 2, characterized in that: In the step 2, the core of the AC electromagnet is a silicon steel sheet.

5. The electromagnetically driven hole-guiding method for aircraft blind area structure according to claim 3, characterized in that: In the step 2, the core of the AC electromagnet is a silicon steel sheet.

6. The electromagnetically driven hole-guiding method for aircraft blind area structure according to claim 1, 2 or 5, characterized in that: The guide member (4) is made of carbon steel and can be attracted by a magnet.

7. The electromagnetically driven hole-making method for an aircraft blind area structure according to claim 3, characterized in that: The guide member (4) is made of carbon steel and can be attracted by a magnet.

8. The electromagnetically driven hole-guiding method for an aircraft blind area structure as claimed in claim 4, characterized in that: The guide member (4) is made of carbon steel and can be attracted by a magnet.

9. An electromagnetically driven hole-guiding device for an aircraft blind area structure, characterized in that: It comprises an electromagnet assembly (3), a guide member (4), a vibration impact assembly (5), a power source (6), and a small annular magnet (7); The electromagnet assembly (3) is used to provide an alternating electromagnetic field, and comprises an electromagnet (3-1), a handle (3-2), a switch (3-3), a cable (3-4), and a plug (3-5). The electromagnet (3-1) and the handle (3-2) are fixed together by bolts, and the plug (3-5) is used to supply power to the electromagnet (3-1) after being inserted into a power source (6); The vibration impact component (5) is used for vibrating under the action of an alternating electromagnetic field to leave a punch mark on a product. The vibration impact component (5) comprises a punch needle (5-1), a permanent magnet A5-2, a permanent magnet B (5-3), and a spring (5-4); wherein the annular permanent magnet A (5-2) and the permanent magnet B (5-3) are nested on both sides of the head of the punch needle (5-1), and the permanent magnet A (5-2) and the permanent magnet B (5-3) attract each other, so that the permanent magnet A (5-2), the permanent magnet B (5-3), the punch needle ( 5-1) is adsorbed as a whole; the spring (5-4) is sleeved on the working rod of the punching needle (5-1) and will not be separated under the magnetic attraction of the permanent magnet B (5-3), thereby assisting the device to generate stable vibration; the working rod of the punching needle (5-1) is sleeved in the inner hole of the guide member (4), and the spring is clamped between the guide member (4) and the head of the punching needle (5-1); the guide member (4) is used to be inserted into the guide hole of the inner layer part (1) of the product to be processed, and the inner hole of the guide member (4) is coaxial with the guide hole of the inner layer part (1).

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