A laser seal repair method

Abstract

The application discloses a laser sealing and welding repair method, which comprises the following steps: clamping a device to be repaired on a workbench; controlling the outer side of a cutting device to be aligned with the inner side of a shell; controlling the Z-axis of the cutting device to cut along a welding track at a preset feed amount, and adopting a downward feeding mode multiple times to feed the cutting device to 70%-95% of the thickness of a cover plate; controlling the working surface of the cutting device to be aligned with the inner side of the shell, and controlling the cutting device to move towards the shell by a preset value; controlling the Z-axis of the cutting device to cut along the welding track at the preset feed amount, and adopting the downward feeding mode multiple times to feed the cutting device to 70%-95% of the thickness of the cover plate; cutting off the metal wires on the shell along the cutting chip side wall, cleaning the surface debris of the device, and prying open the cover plate; after repairing the components and devices in the shell, placing a new cover plate on the shell, and performing laser sealing and welding. The application can ensure high precision, low pollution, high efficiency and good structure recovery effect of the repair work.

Description

Technical Field

[0001] This invention relates to the field of connector welding technology, and specifically to a laser sealing and repair method. Background Technology

[0002] With increasingly stringent reliability requirements for electronic devices and aerospace-grade circuits, stable operation under conditions such as moisture, mechanical shock, and radiation is essential, thus placing higher demands on device packaging. Laser welding utilizes the principle of laser energy radiation, transferring energy through the laser to the overlap between the cover plate and the casing, forming a molten pool at the overlap, which then cools to form a weld. Because the welding trajectory is guided by a programmable laser welding machine, laser sealing can achieve encapsulation of various complex shapes. Furthermore, due to its energy transfer characteristics, it can be used to weld various metal materials, including Kovar alloys, aluminum-silicon alloys, and aluminum alloys. Its molten sealing properties enable high-airtightness packaging, meeting the operating environments of various high-airtightness products, making it one of the primary packaging methods.

[0003] After packaging, most devices undergo a series of tests. These tests may damage internal electronic components or cause other issues, necessitating component replacement. Laser-sealed devices, due to their fusion welding characteristics, are essentially non-repairable. If internal electronic components are damaged, the entire device must be scrapped, which is extremely expensive and should be avoided as much as possible. Summary of the Invention

[0004] The purpose of this invention is to provide a laser sealing repair method to solve the problem of difficult repair after laser sealing in the prior art.

[0005] To achieve the above objectives, the present invention is implemented using the following technical solution: In a first aspect, this application discloses a laser sealing repair method, including: Step 1: Clamp the device to be repaired onto the worktable; wherein the device includes a housing and a cover plate laser-sealed into the stepped groove of the housing; Step 2: Align the outer side of the cutting device with the inner side of the outer casing; Step 3: Control the Z-axis of the cutting device to cut along the welding trajectory with a preset feed rate. Use multiple downward feeds along the welding trajectory to feed the cutting device to 70%-95% of the cover plate thickness. Step 4: Control the working surface of the cutting device to align with the inner side of the outer shell, and control the cutting device to move towards the outer shell by a preset value. Control the Z-axis of the cutting device to cut along the welding trajectory with a preset feed amount. Use multiple downward feeds along the welding trajectory to feed the cutting device to 70%-95% of the cover plate thickness. Step 5: Cut off the metal wire on the outer casing along the chip sidewall, clean the debris from the surface of the device, and pry open the cover plate; Step 6: After repairing the components inside the casing, place the new cover plate on the casing and perform laser sealing.

[0006] Furthermore, aligning the outer side of the cutting device with the inner side of the housing includes: The center of the cutting device is aligned with the welding trajectory of the component; Control the cutting device to move away from the outer casing by half the size of the cutting device.

[0007] Furthermore, the step of clamping the device to be repaired onto the worktable includes: Place the bottom surface of the component to be repaired onto the suction cup, and activate the suction cup to fix the component to be repaired. The electric push rods of multiple floating clamping devices are extended to make the chucks of the floating clamping devices contact the side wall of the device to be repaired. After the chucks contact the side wall of the device to be repaired, the electric push rods are extended by a preset amount to clamp the device to be repaired.

[0008] Furthermore, the cutting device in steps 2, 3, and 4 is a milling cutter with a diameter of 1 mm.

[0009] Furthermore, step 3 includes: The Z-axis feed of the cutting device is controlled to be 25-35% of the cover plate thickness, and the cutting is performed along the welding trajectory. The Z-axis of the cutting device is fed again to 15-25% of the cover plate thickness, and the cutting is performed along the welding trajectory. The Z-axis of the cutting device is fed again to 10-20% of the cover plate thickness, and the cutting is performed along the welding trajectory. The Z-axis of the cutting device is fed again to 8-15% of the cover plate thickness, and the cutting is performed along the welding trajectory. The Z-axis of the control cutting device is fed again to 5-10% of the cover plate thickness, and cutting is performed along the welding trajectory.

[0010] Furthermore, the preset value for controlling the cutting device to move towards the outer shell includes: controlling the cutting device to move towards the outer shell by 0.004-0.005mm.

[0011] Furthermore, both the outer casing and the cover plate of the device are made of metal.

[0012] Furthermore, cleaning the debris on the device surface includes cleaning the debris on the device surface by blowing it with compressed air.

[0013] Furthermore, cutting the metal wires on the outer casing along the chip sidewall includes: using a blade perpendicular to the chip sidewall to cut the metal wires on the outer casing.

[0014] Furthermore, prying open the cover includes: Choose a pry bar or metal sheet as the pry tool; After determining the pry point, place the pry tool against the edge of the cover plate and apply pressure evenly to make the cover plate lift up, gradually widening the opening to pry open the cover plate.

[0015] According to the above technical solution, the beneficial effects of the present invention are as follows: The rework method described in this application employs a multi-feed cutting process, removing metal wires from the outer casing and cleaning debris from the device surface before rework. This ensures high precision, low contamination, high efficiency, and excellent structural restoration during the rework process, significantly improving the performance and lifespan of the reworked device. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the cover plate and the shell after welding according to the present invention; Figure 2 This is a schematic diagram of the laser-sealed cover plate and housing of the present invention; Figure 3 This is a schematic diagram of the cover plate in this invention; Figure 4 This is a schematic diagram of the clamping fixture in this invention; Figure 5 This is a flowchart of the method of the present invention.

[0017] Among them, 1. cover plate; 2. outer shell; 3. milling cutter; 01. stepped groove; 11. suction cup; 12. clamping device; 121. chuck; 122. floating part; 123. electric push rod. Detailed Implementation

[0018] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0019] It should be noted that in the description of this invention, the terms "front," "rear," "left," "right," "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used only for the convenience of describing the invention and do not require the invention to be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on the invention. The terms "front," "rear," "left," "right," "upper," and "lower" used in the description of this invention refer to the directions shown in the accompanying drawings, while the terms "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively.

[0020] like Figure 5As shown, a laser sealing and repair method includes: Step 1: Clamping the component to be repaired onto a worktable; wherein the component includes a housing and a cover plate laser-sealed into a stepped groove in the housing. Step 2: Controlling the outer side of the cutting device to align with the inner side of the housing. Step 3: Controlling the Z-axis of the cutting device to cut along the welding trajectory with a preset feed amount, and using multiple downward feeds along the welding trajectory to feed the cutting device to 70%-95% of the cover plate thickness. Step 4: Controlling the working face of the cutting device to align with the inner side of the housing, and controlling the cutting device to move towards the housing by a preset value, controlling the Z-axis of the cutting device to cut along the welding trajectory with a preset feed amount, and using multiple downward feeds along the welding trajectory to feed the cutting device to 70%-95% of the cover plate thickness. Step 5: Cutting off the metal wire on the housing along the chip sidewall, cleaning the debris on the component surface, and prying open the cover plate. Step 6: After repairing the components inside the housing, placing a new cover plate on the housing and performing laser sealing.

[0021] This application ensures precise alignment between the cutting device and the component to be repaired through clamping in step 1 and alignment of the outer surface with the inner surface in steps 2 and 4, guaranteeing the accuracy of the cutting trajectory. Multiple downward feeds along the welding trajectory further ensure precise control of the cutting depth, avoiding over-cutting or under-cutting and improving the accuracy of the repair work. By cutting to 70%-95% of the cover plate thickness, a certain cover plate thickness is preserved, effectively preventing direct damage to internal components or structures during the cutting process. This layered cutting method also reduces heat accumulation and cutting force during the cutting process, helping to protect heat-sensitive or easily deformed internal components. The multiple downward feeds along the welding trajectory in steps 3 and 4, and the cutting of metal wires and cleaning of debris along the chip sidewall in step 5, effectively reduce the debris generated during the cutting process, preventing it from falling into the component and causing contamination or interference, thus ensuring the performance of the repaired component. Cutting along the welding trajectory, using the original welding boundary as much as possible, helps maintain the structural integrity of the outer shell and new cover plate after installation, ensuring the overall strength and sealing performance of the repaired component.

[0022] The above setup forms a complete rework process, from clamping, precise positioning, layered cutting, debris cleaning to cover plate replacement and sealing welding. This improves rework efficiency and reduces unnecessary intermediate steps and repetitive work.

[0023] like Figures 1-5 As shown, step 1 involves clamping the device to be repaired onto the worktable; wherein the device includes a housing 2 and a cover plate 1 that is laser-sealed and connected to the stepped groove 01 of the housing.

[0024] Specifically, the design of the stepped groove of the outer shell can meet the requirements of laser sealing design, and the placement and fitting accuracy of the cover plate 1 and the outer shell 2 is 0.01.

[0025] In this step, the component to be repaired is clamped onto the worktable. The worktable must be stable, shockproof, and easy to operate to ensure that the component remains stationary during the repair process, avoiding any impact on precision work due to positional movement. Clamping methods include using clamps, suction cups, magnetic bases, locating pins, and bolt fastening.

[0026] Since the component to be repaired (electrical connector) in this application is a thin-walled tubular part, it is necessary to ensure uniform clamping force distribution during clamping to avoid cracking or instability caused by local overload, and to ensure stable clamping of the component to be repaired. Therefore, in a further embodiment of this application, a clamping fixture is also designed. This clamping fixture adopts a combination of suction cups and floating clamping, such as... Figure 4 As shown, the clamping fixture includes a suction cup 11 disposed on the worktable and at least three floating clamping devices 12 disposed on the worktable. The three floating clamping devices 12 are independent of each other and are evenly distributed on the outer periphery of the suction cup 11.

[0027] The floating clamping device 12 includes a chuck 121, a floating part 122, and an electric push rod 123 arranged sequentially. The floating part 122 is spring-fed. Therefore, in this embodiment, clamping the device to be repaired onto the worktable specifically involves: placing the bottom surface of the device to be repaired onto the suction cup 11, activating the suction cup 11 to fix the device; controlling the electric push rods 123 of the multiple floating clamping devices 12 to extend, so that the chuck 121 contacts the side wall of the device to be repaired; after the chuck 121 contacts the side wall of the device to be repaired, controlling the electric push rod 123 to extend by a preset amount to clamp the device to be repaired. After the chuck 121 contacts the device to be repaired, the preset extension amount of the electric push rod 123 is determined according to the spring and the material of the device to be repaired, and is usually set to extend by 2-6 mm.

[0028] In this embodiment, the floating clamping device 12 has a clamping element with micro-displacement capability, allowing the thin-walled tube shell to undergo slight deformation under clamping force, releasing internal stress, and then gradually clamping to the set value, reducing stress concentration during initial clamping. The suction cup 11 has a large contact area with the device to be repaired, ensuring that the adsorption force is evenly distributed on the surface of the device to be repaired, reducing local stress. By combining the suction cup 11 adsorbing the bottom surface with multiple floating clamping devices 12 clamping the sides, the clamping stability of the device to be repaired can be guaranteed, and deformation of the device to be repaired can be prevented.

[0029] Step 2: Align the outer side of the cutting device with the inner side of the outer casing.

[0030] In this step, the cutting device can be a laser cutting device, a waterjet cutting device, a mechanical cutting tool, etc.

[0031] The center of the cutting device is aligned with the welding trajectory of the component; it can be aligned with any point on the welding trajectory. The cutting device is moved by half the size of the cutting device to the side away from the housing; this design ensures that the cover 1 is cut by the cutting device.

[0032] In a further embodiment, the cutting device employs a milling cutter 3. The milling cutter 3 has a diameter of 1 mm and is connected to a machining center milling machine with a rotational speed of 3000 r / min.

[0033] Step 3: Control the Z-axis of the cutting device to cut along the welding trajectory with a preset feed rate. Use multiple downward feeds along the welding trajectory to feed the cutting device to 70%-95% of the cover plate thickness.

[0034] In this step, the Z-axis of the cutting device refers to the axis in the cutting device responsible for controlling the up-and-down movement of the cutting tool. By precisely controlling the movement of the Z-axis, the height of the cutting head relative to the workpiece (cover plate) can be adjusted, thereby changing the cutting depth.

[0035] The welding trajectory can be obtained through scanning or by retrieving the laser welding program. The advantages of cutting along the welding trajectory are: preserving the structural integrity of the outer shell 2 and cover plate 1; cutting along the welding line minimizes the impact on the surrounding area, helps maintain the original structural integrity of the outer shell 2, and reduces overall strength loss.

[0036] Using a multi-feed downward approach for cutting offers several advantages: multiple shallow cuts avoid the damage to the workpiece or cutting tool caused by the excessive heat generated by a single deep cut. Step-by-step cutting reduces the cutting force of each individual cut, minimizing the risk of workpiece deformation or tool wear. By progressively approaching the target depth, the operator can achieve more precise control over the cutting process, especially near the completion stage, contributing to higher cutting accuracy.

[0037] Since the laser welding penetration depth is 40%-60% of the cover plate, this application selects a cutting depth of 70%-95% of the cover plate thickness to ensure complete cutting of the weld joint. This design also preserves a certain thickness: by retaining a portion of the cover plate thickness to maintain its connection with the outer shell 2, it prevents excessively deep cuts from causing accidental damage to internal components, and also ensures that metal shavings generated during the cutting process do not enter the shell, thus preventing damage to internal components.

[0038] Furthermore, firstly, the Z-axis of the cutting device is fed to 30% of the thickness of the cover plate 1, and cutting is performed along the welding trajectory; then, the Z-axis of the cutting device is fed to 25% of the thickness of the cover plate 1 again, and cutting is performed along the welding trajectory; next, the Z-axis of the cutting device is fed to 20% of the thickness of the cover plate 1 again, and cutting is performed along the welding trajectory; then, the Z-axis of the cutting device is fed to 10% of the thickness of the cover plate 1 again, and cutting is performed along the welding trajectory; finally, the Z-axis of the cutting device is fed to 5% of the thickness of the cover plate 1 again, and cutting is performed along the welding trajectory.

[0039] This application employs a five-stage decreasing feed, precisely controlling each stage to adjust the Z-axis feed of the cutting device to a specific percentage (30%, 25%, 20%, 10%, 5%) of the cover plate thickness, thus achieving refined management of the cutting depth. This layered cutting method ensures accurate attainment of the predetermined cutting depth without damaging internal components, thereby improving cutting precision.

[0040] Step 4: Control the working surface of the cutting device to align with the inner side of the outer shell 2, and control the cutting device to move towards the outer shell 2 by a preset value. Control the Z-axis of the cutting device to cut along the welding trajectory with a preset feed amount. Use multiple downward feeds along the welding trajectory to feed the cutting device to 70%-95% of the thickness of the cover plate 1.

[0041] This step is the same as step 3, except that the purpose of this step is to cut the outer casing 2. By cutting the outer casing 2, some metal debris that was stuck to the inside of the outer casing 2 in step 3 can be removed, ensuring the cleanliness of the inner wall of the outer casing 2.

[0042] In one embodiment, the cutting device is preferably extended outward by 0.005 mm. Although the cutting device path is extended outward, due to the presence of the stepped groove 01, even if the cutting device is extended by 0.005 mm, as long as the fitting accuracy reaches 0.01 (i.e., the step height difference is greater than 0.01 mm), the debris will not fall into the device under the action of gravity. This design utilizes the characteristics of the stepped structure to effectively prevent the problem of debris falling.

[0043] Step 5: Cut the metal wire on the outer casing 2 along the chip sidewall, clean the debris from the surface of the device, and pry open the cover plate 1. During the cutting process in steps 3 and 4, metal wires (thin, elongated metal strips) may be generated on the cutting surface. These wires may remain on the housing 2, especially near the cutting edge. This step involves carefully cleaning these metal wires along the sidewalls of the cut surface using appropriate tools (such as pliers, blades, scissors, or a special wire remover) to ensure that the surface of the housing 2 is smooth and free of protrusions. This is crucial for the subsequent installation of the new cover plate 1 and laser sealing.

[0044] Cleaning debris from the device surface: During operations such as cutting and prying open cover plate 1, various debris (such as metal powder, oxides, etc.) may accumulate on the device surface. This step thoroughly removes these debris using ultrasonic cleaning, compressed air blowing, wiping, etc., ensuring that the device surface is clean and free of contaminants. This helps improve the welding quality between the new cover plate 1 and the outer shell 2, preventing foreign objects from affecting electrical performance or causing short circuits.

[0045] The preferred cleaning method is to use compressed air to blow it out.

[0046] Pry open cover 1: After removing the metal wire and cleaning the surface, use a pry bar, screwdriver, or other specialized tools to pry cover 1 off the outer casing 2 along the cut edge. Use moderate force during operation to avoid damaging the outer casing 2 or internal components due to excessive force. Once cover 1 is pried open, the internal components can be repaired.

[0047] Step 6: After repairing the components inside the outer casing 2, place the new cover plate 1 on the outer casing 2 and perform laser sealing.

[0048] In this step: 1. After the cover plate 1 is pried open, the exposed faulty components are diagnosed, replaced, repaired, or adjusted to ensure they return to normal function. This may involve various operations such as circuit testing, component replacement, soldering repair, and parameter adjustment. 2. After completing the internal component repair, the prepared new cover plate 1 is precisely aligned with the corresponding position on the outer shell 2 and placed stably. Ensure that the fit clearance and positional accuracy between the new cover plate 1 and the outer shell 2 meet the design requirements to prepare for subsequent laser sealing. 3. Using laser sealing equipment, precise welding is performed along the joint edge of the new cover plate 1 and the outer shell 2 according to the preset welding parameters (such as power, speed, focal length, etc.). Laser sealing has the advantages of concentrated energy, small heat-affected zone, fast welding speed, and high weld quality. It can form a high-strength, airtight weld joint, ensuring that the new cover plate 1 is firmly and reliably fixed on the outer shell 2, restoring the overall sealing and functionality of the device.

[0049] Prying open cover plate 1 includes: selecting a pry bar or metal sheet as a pry tool; after determining the pry point, fitting the pry tool against the edge of cover plate 1, applying pressure evenly to make cover plate 1 pry up, and gradually widening the opening to pry open cover plate 1.

[0050] In this step, for symmetrically distributed cover plates 1, the prying progress on both sides should be kept as consistent as possible to avoid twisting and deforming cover plates 1 due to one side being completely pried open first. If necessary, two pry bars can be used simultaneously to ensure symmetrical force application. Avoid excessive force: Throughout the prying process, closely monitor the connection between cover plate 1 and housing 2. If significant loosening is felt, immediately reduce the force to avoid excessive prying that could cause cover plate 1 to break or excessive stretching of the connection. For stubborn connection points, try prying from different angles or using a finer tool. Complete separation: When most of cover plate 1 has separated from housing 2, gently hold the edge of cover plate 1 with your hand and use a pry bar to make the final separation at the remaining connection points. Be careful to keep your hand steady and avoid violent shaking or pulling. Clean up residue: After prying open cover plate 1, use a soft cloth or cotton swab to clean any remaining metal wires, debris, or other impurities from the edges of cover plate 1, the stepped grooves of housing 2, and the surface of the components to ensure a clean repair environment.

[0051] In one embodiment, the process of using milling cutter 3 for rework is as follows: First, place the part to be reworked on the milling machine's operating table and align the tool position. Second, set the milling machine program to offset the outer edge of the cover plate 1 inward by 0.5mm, so that the outer side of the milling cutter just contacts the edge of the outer shell 2. Figure 3 As shown. Third step: Start the milling machine, set the Z-axis feed to 0.005mm, and feed downwards multiple times until the milling cutter reaches a depth of 90% of the cover plate 1 thickness (the standard laser welding depth is approximately 40%-60%), preventing debris from falling into the component. Fourth step: Extend the milling machine program outwards (towards housing 2) by 0.005mm, repeating step three to mill away the metal debris adhering to housing 2. With a step and a fit accuracy of 0.01, no debris will fall into the component. Fifth step: Remove the component from the center of the milling cutter's operation, and use an insert to cut away the metal wires adhering to the housing along the chip sidewall. Sixth step: After cleaning the surface debris, use a tool to pry open the cover plate. Seventh step: Replace the repaired component with a new cover plate and perform laser welding again.

[0052] As is known from common technical knowledge, this invention can be implemented through other embodiments that do not depart from its spirit or essential characteristics. Therefore, the disclosed embodiments described above are merely illustrative in all respects and are not the only ones. All modifications within the scope of this invention or its equivalents are included in this invention.

Claims

1. A laser sealing repair method, characterized in that, include: Step 1: Clamp the device to be repaired onto the worktable; wherein the device includes a housing and a cover plate laser-sealed into the stepped groove of the housing; Step 2: Align the outer side of the cutting device with the inner side of the housing, including: The center of the cutting device is aligned with the welding trajectory of the component; Control the cutting device to move away from the outer casing by half the size of the cutting device; Step 3: Control the Z-axis of the cutting device to cut along the welding trajectory with a preset feed rate. Use multiple downward feeds along the welding trajectory to feed the cutting device to 70%-95% of the cover plate thickness. Step 4: Control the working surface of the cutting device to align with the inner side of the outer shell, and control the cutting device to move towards the outer shell by a preset value. Control the Z-axis of the cutting device to cut along the welding trajectory with a preset feed amount. Use multiple downward feeds along the welding trajectory to feed the cutting device to 70%-95% of the cover plate thickness. Step 5: Cut off the metal wire on the outer casing along the chip sidewall, clean the debris from the surface of the device, and pry open the cover plate; Step 6: After repairing the components inside the casing, place the new cover plate on the casing and perform laser sealing.

2. The laser sealing and repair method according to claim 1, characterized in that, The step of clamping the component to be repaired onto the worktable includes: Place the bottom surface of the component to be repaired onto the suction cup, and activate the suction cup to fix the component to be repaired. The electric push rods of multiple floating clamping devices are extended to make the chucks of the floating clamping devices contact the side wall of the device to be repaired. After the chucks contact the side wall of the device to be repaired, the electric push rods are extended by a preset amount to clamp the device to be repaired.

3. The laser sealing repair method according to claim 1, characterized in that, The cutting device in steps 2, 3 and 4 is a milling cutter with a diameter of 1 mm.

4. The laser sealing and repair method according to claim 1, characterized in that, Step 3 includes: The Z-axis feed of the cutting device is controlled to be 25-35% of the cover plate thickness, and the cutting is performed along the welding trajectory. The Z-axis of the cutting device is fed again to 15-25% of the cover plate thickness, and the cutting is performed along the welding trajectory. The Z-axis of the cutting device is fed again to 10-20% of the cover plate thickness, and the cutting is performed along the welding trajectory. The Z-axis of the cutting device is fed again to 8-15% of the cover plate thickness, and the cutting is performed along the welding trajectory. The Z-axis of the control cutting device is fed again to 5-10% of the cover plate thickness, and cutting is performed along the welding trajectory.

5. The laser sealing repair method according to claim 1, characterized in that, The preset value for controlling the cutting device to move towards the outer shell includes: controlling the cutting device to move towards the outer shell by 0.004-0.005mm.

6. The laser sealing repair method according to claim 1, characterized in that, The outer casing and cover of the device are both made of metal.

7. The laser sealing repair method according to claim 1, characterized in that, Cleaning debris from the surface of components includes using compressed air to blow away debris from the surface of components.

8. The laser sealing repair method according to claim 1, characterized in that, Cutting the metal wires on the outer casing along the chip sidewall involves: using a blade held vertically against the chip sidewall to cut the metal wires off the outer casing.

9. The laser sealing repair method according to claim 1, characterized in that, Prying open the cover includes: Choose a pry bar or metal sheet as the pry tool; After determining the pry point, place the pry tool against the edge of the cover plate and apply pressure evenly to make the cover plate lift up, gradually widening the opening to pry open the cover plate.

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