Processing method of thin-wall plastic part

Abstract

The invention discloses a machining method for a thin-wall plastic part. The machining method comprises the steps that S1, a blank material is prepared; s2, fixing the blank material by using a vacuum chuck; s3, the four vertical thin-wall facades are machined in a segmented machining mode, and the first-time machining size of the vertical thin-wall facades does not reach the final forming size of the vertical thin-wall facades; s4, two symmetrically-distributed arc thin-wall vertical faces are milled, and meanwhile cut-off end faces of notch parts are milled at the two ends of the arc length of the arc thin-wall vertical faces; s5, the heights of steps around the four vertical thin-wall vertical faces are milled for the second time, and the size reaches the final forming size; s6, the internal structure of the cavity is milled; s7, the outer circle is milled, and a complete circle of material is reserved on the blank material on the periphery; and S8, the machined part is taken down from the vacuum suction cup, and machining is completed. The whole part cannot be deformed, the percent of pass of part machining is increased, and therefore it is guaranteed that the development task of a newly-developed product is smoothly conducted, and the development progress requirement is met.

Description

Technical Field

[0001] The invention relates to the technical field of milling plastic parts, in particular to a processing method for thin-walled plastic parts. Background Art

[0002] With the development of industrial technology, high-end industrial production has gradually entered people's lives. The production and design of various products need to go through several steps, including drawing design, mold finalization and production manufacturing. Generally, plastic parts are processed by mold finalization, but some plastic parts have too high precision requirements and need to be processed by milling.

[0003] The prior art discloses a comparative document of a material removal processing method for a thin-walled workpiece, with the announcement number: DE102005039148A1, which specifically includes the following processing steps: clamping the blank, removing material from one surface, filling the resulting recess with a filling material, and removing material from other surfaces. For example, wax is suitable as a filling material; the method is particularly suitable for processing plastic parts or other parts that are difficult to process or relatively soft, which means that milling, rotation, grinding, etc. can all be used to achieve the processing of plastic parts, but for plastic parts with smaller volumes and requiring more complex and fine processing, first of all, the filling filler cannot be filled, and thus more fine processing operations cannot be achieved.

[0004] A contactor model Q / JC780-B0N, in which a plastic part - a small cap (such as Figure 1 ), the material is PBT4310 plastic. In the new product development stage, the milling method is used to process the parts. The plastic parts are small in size and require high processing precision. Due to the properties of the material itself and the processing method used, the plastic parts are severely deformed after processing, making most of these plastic parts unable to be put into use. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a method for processing thin-walled plastic parts.

[0006] The present invention is achieved through the following technical solutions.

[0007] The present invention provides a method for processing thin-walled plastic parts, comprising the following steps:

[0008] S1: prepare blank material in the shape of a disc;

[0009] S2: Use vacuum suction cup to fix the blank material;

[0010] S3: Milling four vertical thin-wall facades, using segmented processing to process the dimensions of the four vertical thin-wall facades. The first processing dimensions of the vertical thin-wall facades did not reach the final forming dimensions of the vertical thin-wall facades;

[0011] S4: Milling out two symmetrically distributed arc thin-walled facades, and at the same time milling out the cut end faces of the notch part at both ends of the arc length of the arc thin-walled facade;

[0012] S5: Milling is performed around the two arc thin-wall facades from the notch portion to form a semicircular side wall facade, and a second milling process is performed on the two groups of vertical thin-wall facades. The heights of the four vertical thin-wall facades are increased, and the sizes of the four vertical thin-wall facades reach the final molding size;

[0013] S6: Milling the surrounding excess material to form the internal structure of the cavity, and then milling two circular protrusions and two rectangular grooves inside the cavity;

[0014] S7: Milling the outer circle so that an annular groove is formed between the outer circle and the blank material, and a complete circle of material is retained on the outer blank material, so that the machined part is not completely separated from the outer blank material;

[0015] S8: Remove the processed parts from the vacuum suction cup to complete the processing.

[0016] Preferably, in S2, two locating pins are provided on the vacuum suction cup, and two countersunk holes are milled on the bottom of the blank material. The two countersunk holes are respectively installed on the two locating pins, and the vacuum pump is started. The vacuum suction cup firmly fixes the blank material on the vacuum suction cup, so that the bottom and the two countersunk holes serve as the positioning reference for part processing.

[0017] Preferably, in S3, the step height dimension around the four vertical thin-walled facades is milled to separate the four vertical thin-walled facades, two of the four vertical thin-walled facades form a group, and the two groups of vertical thin-walled facades are symmetrically arranged with the center as the center of the circle.

[0018] Preferably, in S5, the height dimension of the arc thin-walled facade is milled once, and then the cut end surface of the notch part is milled to the required size of the part, and the height dimension of the arc thin-walled facade is no longer processed during the subsequent fine milling of the arc thin-walled facade.

[0019] Preferably, the two groups of vertical thin-walled facades correspond to two arc-shaped thin-walled facades respectively, and the vertical thin-walled facades in the same group are integrally connected to the corresponding arc-shaped thin-walled facades.

[0020] Preferably, in S8, a 5mm wide annular groove is formed between the outer circle and the blank material, a 0.2mm thick material is retained at the bottom of the annular groove, and a complete circle of blank material with a thickness of about 2mm is retained around the periphery of the annular groove.

[0021] Preferably, in S9, the parts removed from the vacuum chuck are placed for 24 hours to release the processing stress and the internal stress of the material through natural aging. After the stress is released, the shape and size of the parts are completely fixed.

[0022] Preferably, the part is separated from the blank material manually, the fitter drills through holes on the two circular protrusions respectively, and removes the flash and burrs on the part to complete the processing.

[0023] The beneficial effects of the present invention are:

[0024] 1. After the semi-finished parts are processed through various processes, a circle of blank materials is retained on the outside, which has a certain protective effect on the overall parts. The semi-finished products are removed from the vacuum suction cup and no longer processed by milling. They are placed in a natural environment for 24 hours. After natural aging, the processing stress and internal stress of the material are released. Since the machined parts are not completely separated from the peripheral blank materials at this time, the formed parts will no longer be deformed. After the stress is released, the shape and size of the parts are completely fixed. The parts and the blank materials are separated manually, so that the overall parts will not be deformed, and the qualified rate of parts processing is improved, thereby ensuring the smooth progress of the new product development task and meeting the development progress requirements.

[0025] 2. When processing vertical thin-walled facades, the dimensions of the vertical thin-walled facades are processed in sections to avoid defects such as corner chipping and deformation during the milling process and to protect the parts as a whole.

[0026] 3. Use vacuum suction cups to clamp and locate parts. On the one hand, the parts are firmly adsorbed to facilitate the subsequent milling of the parts. On the other hand, it avoids squeezing or even damage to the outer side of the parts as much as possible. It has a certain protective effect during the parts processing and ensures the smooth completion of the parts processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the parts structure of the present invention;

[0028] Figure 2 It is a schematic top view of the parts structure of the present invention;

[0029] Figure 3 It is a schematic front view of the parts structure of the present invention;

[0030] Figure 4 It is a schematic side view of the parts structure of the present invention;

[0031] Figure 5 It is a schematic diagram of a blank material of the present invention;

[0032] Figure 6It is a schematic diagram of the structure of the vacuum suction cup of the present invention;

[0033] Figure 7 It is a schematic diagram of the parts processing structure of the present invention mainly processing four vertical thin-wall facades;

[0034] Figure 8 It is a schematic diagram of the parts processing structure of the present invention mainly processing two arc thin-walled vertical surfaces;

[0035] Fig. 9 It is a schematic diagram of the structure of parts mainly for further processing four vertical thin-walled facades and two arc thin-walled facades in the present invention;

[0036] Fig.10 It is a schematic diagram of the structure of the semi-finished parts of the present invention.

[0037] Explanation of the reference numerals: 1 - vacuum suction cup; 101 - positioning pin; 102 - vacuum pump; 2 - vertical thin-wall facade; 3 - arc thin-wall facade; 4 - circular protrusion; 5 - rectangular groove; 6 - annular groove; 7 - countersunk hole. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0040] In an embodiment of the present application, a processing method for a special thin-walled plastic part is provided. The special thin-walled plastic part is a part of a newly developed contactor of model Q / JC780-B0N, and the material used is PBT4310 plastic.

[0041] The specific structure of the parts is as follows Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, this part has four vertical thin-walled facades 2 and two arc thin-walled facades 3. Meanwhile, the four vertical thin-walled facades 2 and the two arc thin-walled facades 3 are all located on the base plate structure.

[0042] This processing method is a processing method for a small cap cover, and the specific steps are as follows:

[0043] S1: Figure 4 As shown, prepare the blank material, the material is made of polybutylene terephthalate resin material, brand PBT4310, the shape is a disc, the size is It is convenient for subsequent clamping and milling processing, and avoids deformation of parts during processing.

[0044] S2: Figure 5 As shown, the blank material is clamped by a vacuum suction cup 1, two positioning pins 101 are arranged on the vacuum suction cup 1, and two countersunk holes 7 are milled at the bottom of the blank material, and the size of the countersunk holes 7 is The two countersunk holes 7 are respectively installed on the two positioning pins 101, and the vacuum pump 102 is started. The vacuum suction cup 1 firmly fixes the blank material on the vacuum suction cup 1, so that the bottom and the two countersunk holes 7 are used as the positioning reference for part processing to fix the blank material.

[0045] The parts are firmly adsorbed, which is convenient for subsequent milling of the parts. The use of the vacuum suction cup 1 can also avoid excessive clamping of the parts, thereby avoiding damage to the parts during the processing, and ensuring the smooth progress of the entire processing of the parts.

[0046] S3: Figure 7 and Figure 8 As shown, four vertical thin-walled facades 2 are milled in a segmented processing manner. The initial models of the four vertical thin-walled facades 2 are milled for the first time, and the step height dimensions around the four vertical thin-walled facades 2 are milled again. The four vertical thin-walled facades 2 are separated and the specific dimensions of the vertical thin-walled facades 2 are milled. The dimensions obtained by this processing do not reach the final molding dimensions, so as to avoid defects such as chipping and deformation. Two vertical thin-walled facades 2 that are close to each other among the four vertical thin-walled facades 2 are divided into a group, so that the two groups of vertical thin-walled facades 2 are symmetrically arranged with the center as the center of the circle.

[0047] S4: Figure 8 As shown, two symmetrically distributed arc thin-walled facades 3 are milled, the height dimension of the arc thin-walled facade 3 is milled in place at one time, and then the cut end face of the notch part is milled to the required size of the part. The height dimension of the arc thin-walled facade 3 is no longer processed during the subsequent fine milling of the arc thin-walled facade 3, so as to avoid multiple milling processes causing material corner chipping.

[0048] S5: Fig. 9As shown, the two arc thin-walled facades 3 are milled around the notch to form a semicircular side wall facade, and the size remains unchanged. The surrounding step heights of the two groups of vertical thin-walled facades 2 are also milled for a second time, so that the heights of the four vertical thin-walled facades 2 are increased. The two groups of vertical thin-walled facades 2 correspond to two arc thin-walled facades 3 respectively, and the vertical thin-walled facades 2 in the same group are integrally connected with the corresponding arc thin-walled facades 3 to form the final forming size.

[0049] S6: Fig.10 As shown, the surrounding excess material is milled to form the internal structure of the cavity, and then two circular protrusions 4 and two rectangular grooves 5 are milled inside the cavity; the outer blank material is retained.

[0050] S7: Fig.10 As shown, the outer circle is milled, and a 5mm wide annular groove 6 is formed between the outer circle and the blank material. A 0.2mm thick material is retained at the bottom of the annular groove 6, and a complete circle of blank material with a thickness of about 2mm is retained around the annular groove 6, so that the processed parts are not completely separated from the peripheral blank material, which facilitates the subsequent separation of the parts and the blank material.

[0051] S8: The parts removed from the vacuum suction cup 1 are placed for 24 hours to allow the parts with blank materials to undergo natural aging and release the processing stress and internal stress of the material. After the stress is released, the shape and size of the parts are completely fixed, the processing is completed, and the formed parts will no longer be deformed.

[0052] S9: The parts are separated from the blank material manually, and the fitter drills through holes on the two circular protrusions 4 respectively, and removes the flash and burrs on the parts, and the processing is completed.

[0053] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A method for processing thin-walled plastic parts, characterized in that: The method comprises the following steps: S1: prepare blank material in the shape of a disc; S2: Use vacuum suction cup (1) to fix the blank material; S3: Milling four vertical thin-walled facades (2), and processing the dimensions of the four vertical thin-walled facades (2) by segment processing. The first processing dimensions of the vertical thin-walled facades (2) do not reach the final forming dimensions of the vertical thin-walled facades (2); S4: milling out two symmetrically distributed arc thin-walled vertical surfaces (3), and at the same time milling out the cut end surfaces of the notched parts at both ends of the arc length of the arc thin-walled vertical surface (3); S5: milling is performed around the two arc thin-walled facades (3) from the notch portion to form a semicircular side wall facade, and the four vertical thin-walled facades (2) are also milled for a second time, the heights of the four vertical thin-walled facades (2) are increased, and the dimensions of the four vertical thin-walled facades (2) reach the final molding dimensions; S6: Milling the surrounding excess material to form the internal structure of the cavity, and then milling two circular protrusions (4) and two rectangular grooves (5) inside the cavity; S7: milling the outer circle so that the outer circle and the blank material form an annular groove (6), and the outer blank material retains a complete circle of material, so that the machined part is not completely separated from the outer blank material; S8: The processed part is removed from the vacuum suction cup (1) to complete the processing.

2. A method for processing thin-walled plastic parts as claimed in claim 1, characterized in that: In the above S2, two positioning pins (101) are arranged on the vacuum suction cup (1), two countersunk holes (7) are milled on the bottom of the blank material, the two countersunk holes (7) are respectively installed on the two positioning pins (101), the vacuum pump (102) is started, and the vacuum suction cup (1) firmly fixes the blank material on the vacuum suction cup (1), so that the bottom and the two countersunk holes (7) serve as positioning references for part processing.

3. A method for processing thin-walled plastic parts as claimed in claim 1, characterized in that: The S3 is to mill the height dimensions of the steps around the four vertical thin-walled facades (2) to separate the four vertical thin-walled facades (2). Two of the four vertical thin-walled facades (2) form a group, and the two groups of vertical thin-walled facades (2) are symmetrically arranged with the center as the center of the circle.

4. A method for processing a thin-walled plastic part as claimed in claim 3, characterized in that: In the above S5, the height dimension of the arc thin-walled vertical surface (3) is milled once, and then the cut end surface of the notch part is milled to the required size of the part. The height dimension of the arc thin-walled vertical surface (3) is no longer processed during the subsequent fine milling of the arc thin-walled vertical surface (3).

5. A method for processing a thin-walled plastic part as claimed in claim 4, characterized in that: The two groups of vertical thin-walled facades (2) correspond to two circular arc thin-walled facades (3) respectively, and the vertical thin-walled facades (2) in the same group are integrally connected with the corresponding circular arc thin-walled facades (3).

6. A method for processing thin-walled plastic parts as claimed in claim 1, characterized in that: The S8 forms a 5mm wide annular groove (6) between the outer circle and the blank material, the bottom of the annular groove (6) retains a 0.2mm thick material, and the periphery of the annular groove (6) retains a complete circle of blank material with a thickness of about 2mm.

7. A method for processing thin-walled plastic parts as claimed in claim 1, characterized in that: In the step S9, the part removed from the vacuum chuck (1) is placed for 24 hours to release the processing stress and the internal stress of the material through natural aging. After the stress is released, the shape and size of the part are completely fixed.

8. A method for processing thin-walled plastic parts as claimed in claim 7, characterized in that: The parts are separated from the blank material manually, and the fitter drills through holes on the two circular protrusions (4) respectively, and removes the flash and burrs on the parts to complete the processing.

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