Method for processing curved surfaces of a foam core

Abstract

The present application relates to the technical field of foam core processing, and particularly relates to a foam core curved surface processing method, comprising the following steps: 1) establishing a blank model and a product model, and importing a programming software; 2) designing a tool processing path through the programming software; 3) using a five-axis machining center to process according to the designed tool processing path, and using a flat-bottom end mill to obtain a final product. The length of the tool needs to be greater than the maximum height of the product, the blade length of the tool needs to be greater than the maximum cutting depth when the product is processed, and the diameter of the tool is determined according to the curved surface shape of the product. The foam core curved surface processing method adopts a flat tool, and the five-axis machining contact material is the flat bottom of the tool, so that the contact surface is larger, the processing efficiency is high, and the processing precision is better. The method of the present application eliminates many processes such as roughing, finishing and corner cleaning in traditional processing, and avoids operations such as tool replacement and tool setting.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of foam core processing, and particularly to a foam core curved surface processing method. BACKGROUND

[0002] Foam cores have the advantages of light weight, high specific strength and specific stiffness, impact resistance, fatigue resistance, excellent corrosion resistance, high temperature resistance, etc., and have been widely used in the fields of aviation, aerospace and high-speed rail. With the in-depth application, the modeling of foam cores is becoming more and more complex.

[0003] At present, the foam core curved surface processing basically adopts ball knives or R-angle cutters for processing, and this method has the following limitations or deficiencies:

[0004] (1) The method of using ball knives or R-angle cutters for processing has low processing efficiency because the contact surface between the cutter and the material is the vertex of the ball knife or the R-angle cutter.

[0005] (2) Since the R-angle cutter is used to finish process the foam core curved surface, there are many residual materials on the foam curved surface, and the precision is not high; if the precision is high, the processing efficiency will be very low.

[0006] (3) Since the R-angle cutter is not suitable for roughing, there is an operation of changing the cutter in the processing, which not only needs to install more cutters, but also needs additional positioning of the cutter and numerical control programming.

[0007] Therefore, it has become one of the difficult problems to be solved in the field to design a new foam core curved surface processing method with higher processing efficiency and processing precision. SUMMARY

[0008] The purpose of the present application is to provide a foam core curved surface processing method.

[0009] To achieve the above purpose, the present application provides the following technical scheme:

[0010] A foam core curved surface processing method, comprising the following steps:

[0011] (1) Establishing a blank model and a product model, and importing a programming software; (2) designing a cutter processing path through the programming software; (3) using a five-axis machining center to process with a flat-bottom end mill according to the designed cutter processing path, to obtain a final product.

[0012] In the step (2), according to the embryo model and the shape of the product, the excess amount required for processing is determined, so that the tool used is determined. Wherein, the length of the tool needs to be greater than the maximum height of the product, the blade length of the tool needs to be greater than the maximum cutting depth when the product is processed, and the diameter of the tool is determined according to the shape of the curved surface of the product. The simpler the UV curvature of the curved surface of the product is, the larger the diameter of the tool is; the more complex the UV curvature of the curved surface of the product is, the smaller the diameter of the tool is.

[0013] In the step (3), the top of the product is processed first, and the bottom surface of the tool is always tangent to the curved surface of the top of the product; when the embryo to be processed is not greater than the blade length, the cutting can be completed in one step; when processing, the speed of the machine tool is 10000r / min, the feed is 3000mm / min, the tool extension length needs to be greater than the cutting height, and the step distance of the tool is not greater than 60% of the diameter of the tool; if the embryo amount is too large, part of the material needs to be cut off in advance to prevent collision with the tool and cause damage to the material.

[0014] After the top of the product is processed, the side wall of the product is processed, and the side blade of the tool is always attached to the side wall to process the complex side surface in one step;

[0015] If the curvature of the side wall is complex, the bottom surface of the tool can be tangent to the curved surface of the side wall of the product, and when processing, the speed of the machine tool is 10000r / min, the feed is 3000mm / min, the tool extension length needs to be greater than the cutting height, and the step distance of the tool is not greater than 60% of the diameter of the tool.

[0016] In the step (3), the embryo is processed by adopting the adsorption type fixation or using the double-sided adhesive tape and the limiting block for fixation.

[0017] If the product is a double curved surface, 50% or less of the depth of the side wall can be processed first when the side wall is processed, and the remaining amount of the side wall is processed after the reverse curved surface is processed; finally, part of the material needs to be left, and the burr and the reserved fixing material are removed manually.

[0018] If the UV curvature of the product is a hyperbolic structure, most of the embryo can be removed first, and the remaining amount can be removed by a ball cutter or a smaller flat cutter.

[0019] The programming software can adopt any one of UG, MASTERCAM, WORKNC and Powermill.

[0020] Compared with the prior art, the foam core curved surface processing method has the following advantages:

[0021] (1) The foam core curved surface processing method adopts a flat cutter, contacts the material with the bottom of the flat cutter in five-axis processing, and has a larger contact surface, so that the processing efficiency is high and the processing precision is better.

[0022] (2) The method of the present application eliminates many processes of roughing, finishing and corner cleaning in traditional processing, and avoids tool changing and tool setting operations.

[0023] (3) Compared with the traditional ball cutter or R-angle cutter processing method, the method of the present application greatly improves the processing efficiency and processing precision. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a schematic view of a flat-bottomed end mill;

[0025] Figures 2-4 is a schematic view of processing paths for processing different curved surfaces using the foam core curved surface processing method of the present application;

[0026] Figure 5 is a schematic view of processing a side wall using the foam core curved surface processing method of the present application;

[0027] Figure 6 is a schematic view of a product processed in an example. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0029] EMBODIMENT

[0030] A foam core curved surface processing method, comprising the following steps:

[0031] 1) A blank model and a product model are established using UG software, and then imported into the UG software.

[0032] 2) A tool processing path is designed by UG programming software; according to the blank model and the shape of the product, the required processing allowance is determined, so as to determine the tool used. As shown in the figure, the length L2 of the tool needs to be greater than the maximum height of the product, the blade length L1 of the tool needs to be greater than the maximum cutting depth when the product is processed, and the tool diameter D1 is determined according to the shape of the product curved surface. The simpler the UV curvature of the product curved surface is, the larger the tool diameter is; the more complex the UV curvature of the product curved surface is, the smaller the tool diameter is. Figure 1

[0033] 3) A five-axis machining center is used to process according to the designed tool processing path, and a flat-bottomed end mill is used to process to obtain the final product.

[0034] ​In the embryo processing, the adsorption type fixing or the double-sided tape and the limiting block are adopted for fixing, and if the double-sided tape is adopted, the thickness of the tape needs to be considered to affect the precision of the product.

[0035] In the processing, the top of the product is processed first, and the bottom surface of the cutter is always tangent to the curved surface of the top of the product. Figures 2-4 For the machining path of the common different curved surfaces, when the embryo to be processed is not greater than the length of the blade, the cutting can be completed in one step; in the processing, the rotating speed of the machine tool is 10000r / min, the feeding is 3000mm / min, the extension length of the cutter needs to be greater than the cutting height, and the step distance of the cutter is not greater than 60% of the diameter of the cutter; if the embryo is too large, part of the material needs to be cut in advance to prevent the collision of the cutter from causing the damage of the material.

[0036] As shown in Figure 5 , after the top of the product is processed, the side wall of the product is processed, the side blade of the cutter is always attached to the side wall, and the complex side surface is processed in one step.

[0037] If the curvature of the side wall is complex, the bottom blade of the cutter can be used to process the side wall, and the bottom surface of the cutter is tangent to the curved surface of the side wall of the product; in the processing, the rotating speed of the machine tool is 10000r / min, the feeding is 3000mm / min, the extension length of the cutter needs to be greater than the cutting height, and the step distance of the cutter is not greater than 60% of the diameter of the cutter. When the bottom blade of the cutter is used to process the side wall, the material generally needs to be raised to facilitate the five-axis rotary processing to have enough space.

[0038] If the product is a double curved surface, 50% or less of the depth can be processed when the side wall is processed, and the remaining amount of the side wall is processed after the reverse curved surface is processed; finally, part of the material needs to be left, and the burr and the reserved fixing material are removed manually.

[0039] If the UV curvature of the product is a hyperbolic structure, the above processing method can be used to remove most of the embryo, and the remaining amount can be removed by a ball cutter or a smaller flat cutter.

[0040] The above processing method is used to process a PMI foam product, and the shape of the product is as shown in Figure 6 .

[0041] In order to highlight the beneficial effects of the application, the ball cutter is used to process the above product (the processing method of the R-angle cutter is similar to that of the ball cutter, and is not repeated here), and the processing method is as follows:

[0042] The comparative example adopts the ball cutter to process

[0043] The processing method includes the following steps:

[0044] 1) First, the top of the whole embryo is roughened by using a flat knife. The step distance is 60% of the diameter of the tool. The rotation speed is 10000 r / min, the feed is 3000 mm / min, and a 1 mm allowance is left.

[0045] 2) The curved surface is finished by using a ball knife, and the step distance is 0.5-0.2 mm. The rotation speed is 10000 r / min, and the feed is 5000 mm / min.

[0046] 3) The side wall is roughened by using a flat knife, and a 1 mm allowance is left. The down-cutting amount is 5-10 mm, the rotation speed is 10000 r / min, and the feed is 3000 mm / min.

[0047] 4) Then, the ball knife is used for finishing, and the down-cutting amount is gradually changed according to the curvature. The down-cutting amount can be slightly larger in the steeper area, and the down-cutting amount is smaller in the flatter area. The basic range is between 0.2-0.8 mm. The rotation speed is 10000 r / min, and the feed is 5000 mm / min.

[0048] 5) Finally, the corner processing is locally performed according to the processing effect, and the part is removed.

[0049] The processing method of the comparative example is compared with the processing method of the embodiment, and the results are as follows:

[0050] (1) First, the ball knife / R angle knife is used for processing, and the tool needs to be replaced constantly, while the processing method of the embodiment can not replace the tool, which saves the tool changing and tool setting time and reduces the tool cost.

[0051] (2) When the curved surface is processed by using the ball knife / R angle knife, not only roughing is needed, but also the step distance of finishing is very small, otherwise the curved surface is rough and the processing time is long. In comparison, the processing time of the embodiment is only 1 / 10 of that of the comparative example. Although the time ratio of different shapes of products is different, the processing efficiency of the method of the embodiment can be improved by at least five times.

[0052] (3) The contact surface of the R angle and the curved surface is always a point, and the curved surface processed is generally rough, unless a very small step distance is used; while in the processing method of the embodiment, the flat knife contacts the curved surface with a large area, which not only improves the processing efficiency, but also improves the curved surface effect, and is more in line with the requirements of foam products.

[0053] Although the embodiments of the present application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A method of curved surfacing of a foam core material, characterized by, The method comprises the following steps: (1) establishing a blank model and a product model, and importing a programming software; (2) designing a tool machining path through the programming software, determining a required machining allowance according to the blank model and the shape of the product, thereby determining a tool to be used, the length of the tool needs to be greater than the maximum height of the product, the blade length of the tool needs to be greater than the maximum cutting depth during machining of the product, the diameter of the tool is determined according to the shape of the product curved surface, the simpler the UV curvature of the product curved surface is, the greater the diameter of the tool is, and the more complex the UV curvature of the product curved surface is, the smaller the diameter of the tool is; (3) machining the product to obtain a final product by using a five-axis machining center according to the designed tool machining path and using a flat-bottom end mill; the top of the product is machined first, the bottom surface of the tool is always tangent to the curved surface of the top of the product, when the blank to be machined is not greater than the blade length, the cutting can be completed in one step, the machining speed of the machine tool is 10000r / min, the feeding is 3000mm / min, the tool extension length needs to be greater than the cutting height, and the step distance of the tool is not greater than 60% of the diameter of the tool; if the amount of the blank is too large, part of the material needs to be cut in advance to prevent collision of the tool and damage of the material; the side wall of the product is machined after the top of the product is machined, the side blade of the tool is always attached to the side wall, and the complex side surface is machined in one step; if the curvature of the side wall is complex, the bottom surface of the tool can be tangent to the curved surface of the side wall of the product, the machining speed of the machine tool is 10000r / min, the feeding is 3000mm / min, the tool extension length needs to be greater than the cutting height, and the step distance of the tool is not greater than 60% of the diameter of the tool; if the product is a double curved surface, 50% or less of the depth of the side wall can be machined first when the side wall is machined, the remaining allowance of the side wall is machined after the machining of the reverse curved surface is completed, and part of the material needs to be reserved for manual removal of burrs and reserved fixing material.

2. The method of claim 1, wherein: In the step (3), the blank is fixed by adsorption or fixed by using double-sided tape and a limiting block.

3. The method of claim 2, wherein: If the UV curvature of the product is a hyperbolic structure, most of the blank can be removed first, and the remaining allowance can be removed by a ball cutter or a smaller flat cutter.

4. The method of claim 3, wherein: The programming software can be any one of UG, MASTERCAM, WORKNC and Powermill.

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