Processing method of burr-free lug clamp spring

Abstract

The invention discloses a processing method of a burr-free lug clamp spring. The processing method comprises the following steps: step 1, punching a positioning hole and two small holes; 2, pre-cutting and leveling are conducted, specifically, the blank is preliminarily separated through a pre-cutting and leveling die, and a blanking gap Z is controlled to be larger than or equal to t * 5% and smaller than or equal to t * 8% at the thickness t of a stamped profile, so that the blank is leveled, and the angle collapse of a blanking section is reduced; 3, positive and negative pressure flashing is carried out, positive and negative pressure flashing treatment is carried out on the blank piece and the small holes in the blank piece along the circumference through a positive and negative pressure flashing mold, burrs are removed through the profiling design of a boss and a sinking table, and secondary leveling of the blank piece is completed; step 4, blanking; and 5, waste is cut off. The stamping die can replace an existing process scheme to effectively solve the problem of burrs of stamped products.

Description

Technical Field

[0001] The invention belongs to the technical field of stamping and specifically discloses a processing method of a hairless and piercing-free clip spring. Background Art

[0002] like Figure 1 As shown in the figure, the ear spring is a key fastener in the engine system, and plays an irreplaceable role in ensuring the positioning and assembly reliability of parts. This part belongs to the category of open C-shaped retaining rings, and its structural design is unique: the overall C-shaped opening, with an eccentricity of about 2 mm between the inner and outer circles, this special geometric configuration not only ensures that it has good elastic deformation ability, but also provides convenience for its installation and disassembly.

[0003] In terms of the performance indicators of the ear circlip, the requirements for its flatness are particularly stringent. The technical specifications clearly stipulate that the flatness of the upper and lower surfaces of the product must be controlled within 0.1 mm. This strict tolerance requirement stems from its important function in the engine assembly process: ensuring a close fit with the mating surface to prevent loosening or displacement during engine operation. However, this high-precision processing requirement also brings significant manufacturing difficulties, that is, burrs are easily formed on the edges of parts during the production process.

[0004] To address the burr problem, the traditional production process adopts a continuous operation mode of "stamping - deburring - heat treatment - phosphating - packaging and warehousing". Among them, the deburring process usually relies on mechanical treatment methods such as rolling or shot blasting. However, these traditional deburring processes have obvious limitations: first, the mechanical deburring process is prone to cause irregular scratches on the surface of the parts. These surface defects not only affect the aesthetics of the product, but are also likely to damage its anti-corrosion performance; second, in the batch processing process, parts are prone to entanglement and hooking, which significantly reduces the efficiency of the subsequent packaging process.

[0005] More importantly, the existing process faces severe challenges in large-scale production. Due to the efficiency bottleneck of the deburring process and the large amount of manpower required for parts sorting and sorting in the packaging process, the entire production line is difficult to meet the needs of large-scale, continuous and stable delivery. This not only increases production costs, but also affects the company's delivery capabilities and market competitiveness.

[0006] Therefore, it is urgent to develop a technical solution for solving the burr problem in the processing of the above-mentioned ear clips. Summary of the invention

[0007] In view of the technical problems in the background technology, the present invention discloses a method for processing a burr-free retaining spring, which can replace the existing process solutions and effectively solve the burr problem of stamping products.

[0008] The invention discloses a processing method for a hairless and burr-free circlip, which comprises the following steps: step 1: punching a positioning hole and two small holes, and ensuring the step accuracy of continuous die feeding by punching the positioning hole, and satisfying the design requirements of the circlip by punching the two small holes, so as to provide a positioning and processing basis for subsequent processes; step 2: pre-cutting and leveling, preliminarily separating the blanks by pre-cutting and leveling dies, and controlling the blanking gap Z within the thickness t of the stamping profile, t*5%≤Z≤t*8%, so as to level the blanks and reduce the blanking breakage. Surface collapse angle; Step 3: Positive and negative pressure burring, the blank and the small holes on it are subjected to positive and negative pressure burring treatment along the circumference through the positive and negative pressure burring mold, and the burrs are eliminated and the secondary leveling of the blank is completed by using the contour design of the boss and the sinker; Step 4: Blanking, the blank is completely separated from the material belt through the blanking die, and the blank is collected along the slide by gravity; Step 5: Cutting off the waste, cutting the waste by the upper and lower waste cutting punches and concave dies, and the waste slides into the waste box under the action of gravity to complete the waste collection.

[0009] In a preferred embodiment of the present invention, the following step is also included between step 1 and step 2: misfeed sensing detection, by automatically detecting the accuracy of the feeding step and transmitting the detection signal to the stamping equipment in real time, to achieve automated coordinated operation of the continuous mold and the stamping equipment.

[0010] In a preferred embodiment of the present invention, the pre-cutting and leveling mold includes a pre-cutting and leveling die and a pre-cutting and leveling punch. The pre-cutting and leveling die is provided with a die hole corresponding to the shape of the ear retaining spring, and the pre-cutting and leveling punch is provided with a pressure head corresponding to the shape of the ear retaining spring. The pre-cutting and leveling blanking gap Z = the outer diameter of the die hole - the outer diameter of the pressure head, t*5%≤Z≤t*8%, and t is the thickness of the stamping profile.

[0011] In a preferred embodiment of the present invention, the pre-cut depth h1, 80% of the thickness of the stamped profile ≤ h1 ≤ the thickness of the stamped profile * 90%.

[0012] In a preferred embodiment of the present invention, the positive and negative pressure flashing mold includes a positive and negative pressure flashing punch and a positive and negative pressure flashing die, the positive and negative pressure flashing punch has a first boss and a second boss corresponding to the shape of the ear retaining ring, the first boss is used to form the outer shape of the ear retaining ring, and the second boss is used to form the small hole on the ear retaining ring.

[0013] In a preferred embodiment of the present invention, the height of the first boss is 0.6-0.8 times the thickness t of the stamped profile; the outer diameter of the first boss The value is The height h3 of the second boss is 0.5-0.7 times the thickness t of the stamping profile.

[0014] In a preferred embodiment of the present invention, the diameter of the second boss is The value is The taper of the second boss is 30°; the transition radius of the second boss is generally 0.2-0.5 mm.

[0015] In a preferred embodiment of the present invention, the depth of the sink is 0.6-0.8 times the thickness t of the stamped profile; the diameter of the sink is The value is The taper of the sinker is 30°; the transition radius of the sinker is 0.2-0.5mm.

[0016] In a preferred embodiment of the present invention, the pre-cutting and leveling mold also includes a pre-cutting and leveling top material block, on which is provided a top head corresponding to the shape of the ear spring, and on the pre-cutting and leveling die is provided a groove corresponding to the shape of the pre-cutting and leveling top material block, and the groove is connected to the mold hole.

[0017] In a preferred embodiment of the present invention, the boss and the sink of the positive and negative pressure flashing mold are both designed in a contoured manner and have a taper and a rounded corner.

[0018] The present invention has the following beneficial effects: First, the present invention has a simple structure and is easy to use. By adopting a continuous die design, it realizes the automated production of continuous stamping of ear clips without burrs, and solves the problems of complicated process flow and unstable product quality of mechanical deburring such as rolling and shot blasting, thereby greatly improving the production process accuracy, production capacity and service life of the product, and effectively reducing the production cost of the product. Secondly, the present invention solves the positioning error problem caused by the unstable feeding of the three-in-one feeder by optimizing the feeding system, so that the processing accuracy and continuity of the parts are greatly improved. In addition, by introducing pre-cut leveling dies and positive and negative pressure burring dies, the present invention effectively solves the problem of unqualified flatness of continuously stamped parts, and stably controls the flatness within the customer's technical requirements. At the same time, it completely solves the problem of burrs on the end faces of continuous stamping, and realizes positive and negative pressure burring along the circumference of the parts and two small holes, thereby significantly improving the quality level and service life of the product.

[0019] At the same time, the present invention adopts precise mold design and process control in the stamping process, which solves the problem of scratches and indentations on the surface of parts during continuous stamping and blanking, and greatly improves the appearance quality level of parts. At the same time, the present invention integrates the process links of stamping, pre-cutting and leveling, positive and negative pressure burring, etc., which significantly improves production efficiency and reduces production costs, meets the needs of large-scale production, and significantly improves the delivery capacity and market competitiveness of enterprises. In summary, the present invention not only solves many technical problems in the traditional processing technology of ear retaining springs, but also achieves significant improvements in production efficiency, processing accuracy, cost control and product quality, providing an efficient and feasible solution for the large-scale and high-quality production of ear retaining springs. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions being implemented, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. It is obvious that the accompanying drawings described below are embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0021] Figure 1 This is the front view of the ear circlip;

[0022] Figure 2 It is a schematic diagram of a layout of a processing method of a hairless and piercing-free circlip of the present invention;

[0023] Figure 3 It is a schematic diagram of a continuous die for realizing a method for processing a hairless and piercing retainer according to the present invention;

[0024] Figure 4 The schematic diagram of continuous mold arrangement for realizing a method for processing a hairless and piercing retainer according to the present invention is

[0025] Figure 5 It is a schematic diagram of a continuous die for realizing a method for processing a hairless and piercing retainer according to the present invention;

[0026] Figure 6 It is a schematic diagram of a continuous die pre-cutting and leveling die for realizing a method for processing a hairless and piercing retainer according to the present invention;

[0027] Figure 7 yes Figure 6 A partial enlarged view of;

[0028] Figure 8 It is a cross-sectional view of a continuous die positive and negative pressure flashing die for realizing a method for processing a hairless and piercing clip according to the present invention;

[0029] Fig. 9 yes Figure 8 B is a partial enlarged view of;

[0030] Fig.10 It is a schematic diagram of a continuous die pre-cutting and leveling punch for realizing a method for processing a hairless and piercing retainer according to the present invention;

[0031] Fig.11 It is a schematic diagram of a continuous die pre-cutting and leveling concave die for realizing a method for processing a hairless and piercing retainer according to the present invention;

[0032] Fig.12 It is a schematic diagram of a continuous die positive and negative pressure flashing punch for realizing a method for processing a hairless and piercing clip according to the present invention;

[0033] Fig.13 It is a top view of a continuous die positive and negative pressure flashing punch die for realizing a method for processing hairless and piercing retaining rings of the present invention;

[0034] Fig.14 It is a cross-sectional view of a continuous die positive and negative pressure flashing punch die for realizing a method for processing a hairless and piercing retaining ring of the present invention;

[0035] Fig.15 yes Figure 4 D partial enlarged view;

[0036] Fig.16 It is a schematic diagram of a continuous die positive and negative pressure flashing die for realizing a method for processing a hairless and piercing retaining ring of the present invention;

[0037] Fig.17 It is a cross-sectional view of a continuous die positive and negative pressure flashing die for realizing a method for processing a hairless and piercing retaining ring of the present invention;

[0038] Fig.18 yes Fig.17 D partial enlarged view;

[0039] Fig.19 It is a schematic diagram of the mold hole and the pressure head gap of the continuous mold pre-cutting and leveling mold for realizing a method for processing hairless and piercing retaining rings of the present invention;

[0040] Fig. 20 It is a schematic diagram of the application of the continuous mold of the present invention;

[0041] Fig.21 It is a schematic diagram comparing the effects of using the continuous mold of the present invention. DETAILED DESCRIPTION

[0042] The technical solution of the present invention (including the preferred technical solution) is further described in detail below by means of the accompanying drawings and by listing some optional 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.

[0043] The present invention relates to a method for processing a hairless and piercing-free clip spring. The specific implementation manner of the present invention is described in detail below in conjunction with the accompanying drawings.

[0044] The continuous die of the present invention adopts an innovative process design, completely eliminating the rolling and deburring process in the traditional process, and realizing continuous burr-free processing of parts by reasonably arranging various workstations on a set of continuous dies.

[0045] The invention discloses a processing method for a hairless and burr-free circlip, comprising the steps of: 1, punching a positioning hole, the purpose of which is to ensure the accurate feeding step of a continuous die and to assist in guiding and positioning subsequent workstations; punching two small holes, the purpose of which is to pre-punch two small holes of required sizes of the product before the misfeeding induction detection step according to the product size requirements;

[0046] Step 2: misfeeding induction detection, the purpose of which is to automatically detect the accuracy of the feeding step and transmit the detection signal to the stamping equipment in real time to achieve continuous automated production of continuous dies and stamping equipment;

[0047] Step 3, pre-cutting and leveling, is an important station of the present invention, and its purpose is to separate the blank into the shape of the product by pre-cutting, so that the blank meets the product size requirements and is "separated" from the material strip, and at the same time, the blank is leveled by controlling the height difference between the top material block and the pre-cutting and leveling die, and the blanking clearance of the pre-cutting and leveling convex and concave dies is controlled so that the blank and the two small holes can be punched forward and backward along the circumference by the subsequent station;

[0048] Step 4, positive and negative burring, is an important workstation of the present invention, and its purpose is to perform positive and negative burring on the blank and the two small holes. The burring convex and concave dies are designed with a boss or sinker with a taper and a rounded corner and a certain gap reserved according to the product shape and the aperture for profiling. The blank is first pushed back in the direction of the material strip by the burring convex die, so that the burr surface of the blank is completely exposed outside the material strip, and then the blank and the two small holes are burred positively and negatively along the circumference by the burring convex and concave die, so as to realize continuous stamping without burrs, and the blank is leveled twice to simplify the mold structure of the pre-cutting and leveling step;

[0049] Step 5, blanking, the purpose of which is to completely separate the blank from the material strip by the blanking punch, and use the blank's own gravity to slide out of the mold area along a dedicated slide in an orderly manner to collect the blank;

[0050] Step 6, cutting off the waste, the purpose of which is to automatically cut off the waste by cutting the upper and lower waste cutting convex and concave dies against each other, and the waste slides into the waste box along the inclined waste chute under the action of gravity for waste collection.

[0051] The method of the present invention is based on Figure 2-20The continuous die shown in the figure is realized, and the continuous die is arranged in sequence along the feeding direction of the stamping profile with a punching and guiding hole and small hole die 1, a pre-cutting and leveling die 4, a positive and negative pressure flashing die 5, a blanking die 2 and a cutting die 3. Through this scientific station arrangement, the processing tasks of punching, pre-cutting and leveling, positive and negative pressure flashing, blanking and cutting off waste materials of parts can be completed in sequence, and finally a high-quality ear spring product with no burrs along the circumference can be obtained.

[0052] In terms of mold structure design, the pre-cutting and leveling mold 4 is an important innovation of the present invention. The mold includes two main parts: a pre-cutting and leveling die 41 and a pre-cutting and leveling punch 42. The pre-cutting and leveling die 41 is precisely processed with a die hole that completely corresponds to the shape of the ear clip, and the pre-cutting and leveling punch 42 is designed with a pressure head that matches the shape of the ear clip. In order to ensure the processing quality, the pre-cutting and leveling punch 42 is installed above the stamping profile, while the pre-cutting and leveling die 41 is located below the stamping profile. This upper and lower structural design can ensure stability and accuracy during the processing.

[0053] The present invention introduces precise parameter control in the pre-cutting and leveling process. The pre-cutting and leveling blanking gap Z, that is, the difference between the outer diameter of the die hole and the outer diameter of the punch, is strictly controlled within a specific range: t5% ≤ Z ≤ t8% (where t is the thickness of the stamping profile). This precise gap control plays a key role in ensuring the processing quality. At the same time, the pre-cutting depth h1 is also strictly controlled between 80% and 90% of the thickness of the stamping profile. This precise depth control ensures that the workpiece can achieve the ideal state of "seemingly separated but not separated", creating favorable conditions for the subsequent flashing process.

[0054] The design of the positive and negative pressure flashing mold 5 also reflects the innovation of the present invention. The mold includes a positive and negative pressure flashing punch 51 and a positive and negative pressure flashing die 52. A sink corresponding to the shape of the ear circlip is designed on the positive and negative pressure flashing die 52, and a boss corresponding to the shape of the ear circlip is designed on the positive and negative pressure flashing punch 51. Among them, the design of the boss is particularly exquisite, including two parts with different functions: a first boss for forming the main body of the ear circlip and a second boss for forming the upper hole of the ear circlip. The first boss completely corresponds to the shape of the ear circlip, and the second boss is located on the first boss and is arranged one by one corresponding to each hole on the ear circlip.

[0055] In terms of specific dimensional parameters, the present invention has been strictly controlled. The height of the first boss is controlled to be 0.6-0.8 times the thickness t of the stamping profile. The following conditions must be met: The design of the second boss is also precise, and its height h3 is controlled to be 0.5-0.7 times the thickness t of the stamping profile. Need to meet: In addition, the second boss adopts a 30° taper design, and the transition radius is generally 0.2-0.5mm. The precise control of these parameters ensures the processing quality.

[0056] The design of the sink is also important. Its depth is controlled to be 0.6-0.8 times the thickness of the stamping profile. Need to meet: The sink table also adopts a 30° taper design, and the transition radius is 0.2-0.5mm. The precise control of these parameters is crucial to achieve burr-free processing.

[0057] In order to further improve the processing quality, the present invention further adds a pre-cutting and leveling top material block 43 in the pre-cutting and leveling die, on which a head corresponding to the shape of the ear clip is designed. Accordingly, a groove corresponding to the shape of the pre-cutting and leveling top material block 43 is provided on the pre-cutting and leveling concave die 41, and the groove is connected to the die hole. This design can not only improve the positioning accuracy of the workpiece, but also ensure the stability of the processing process.

[0058] The working principle of the present invention is to pre-cut the blank before blanking, and accurately control the pre-cut depth and gap. The pre-cut depth h1 is controlled between 80-90% of the blank material thickness t. This control ensures that the blank and the material strip are in a "separated but not separated" state, and at the same time plays a leveling role on the blank. The gap Z between the pre-cut convex and concave dies is controlled between 5-8% of the blank material thickness t. This precise control can effectively reduce the collapse angle θ1 of the blanking section, creating favorable conditions for the ejection of the subsequent stations and the positive and negative pressure flashing along the circumference.

[0059] In terms of the overall layout of the mold, the present invention adopts an innovative design. The positive and negative punching convex die is installed on the lower fixed plate, and the concave die is installed on the upper fixed plate. The bosses or sinks of the positive and negative punching convex and concave dies are carefully designed to be similar to the product shape and have tapers and chamfers. During the processing, the blank is pressed into the positive and negative punching concave die through the downward movement of the upper die, so that the blank and the two small holes are punched along the circumference, thereby achieving the purpose of continuous stamping parts without burrs on the end face.

[0060] The present invention can be combined with a three-in-one feeder to form an automatic production line. The coil is fed into the continuous die area through the three-in-one feeder. Under the action of the stamping equipment, it passes through the steps of punching the positioning hole and two small holes, misfeeding induction detection, pre-cutting leveling, positive and negative pressure burring, blanking, and cutting off the waste material, thus realizing the fully automated production of continuous stamping parts without burrs. The specific method steps are:

[0061] Step 1: Punch the positioning hole, the purpose of which is to ensure the accurate feeding step of the continuous die, and at the same time play an auxiliary role in guiding and positioning the subsequent stations; Punch two small holes, the purpose of which is to pre-punch two small holes of the required size of the product before the misfeeding induction detection step according to the product size requirements;

[0062] Step 2: misfeeding induction detection, the purpose of which is to automatically detect the accuracy of the feeding step and transmit the detection signal to the stamping equipment in real time to achieve continuous automated production of continuous dies and stamping equipment;

[0063] Step 3, pre-cutting and leveling, is an important station of the present invention, and its purpose is to separate the blank into the shape of the product by pre-cutting, so that the blank meets the product size requirements and is "separated" from the material strip, and at the same time, the blank is leveled by controlling the height difference between the top material block and the pre-cutting and leveling die, and the blanking clearance of the pre-cutting and leveling convex and concave dies is controlled so that the blank and the two small holes can be punched forward and backward along the circumference by the subsequent station;

[0064] Step 4, positive and negative burring, is an important workstation of the present invention, and its purpose is to perform positive and negative burring on the blank and the two small holes. The burring convex and concave dies are designed with a boss or sinker with a taper and a rounded corner and a certain gap reserved according to the product shape and the aperture for profiling. The blank is first pushed back in the direction of the material strip by the burring convex die, so that the burr surface of the blank is completely exposed outside the material strip, and then the blank and the two small holes are burred positively and negatively along the circumference by the burring convex and concave die, so as to realize continuous stamping without burrs, and the blank is leveled twice to simplify the mold structure of the pre-cutting and leveling step;

[0065] Step 5, blanking, the purpose of which is to completely separate the blank from the material strip by the blanking punch, and use the blank's own gravity to slide out of the mold area along a dedicated slide in an orderly manner to collect the blank;

[0066] Step 6, cutting off the waste, the purpose of which is to automatically cut off the waste by cutting the upper and lower waste cutting convex and concave dies against each other, and the waste slides into the waste box along the inclined waste chute under the action of gravity for waste collection.

[0067] It should be pointed out that punching, blanking and cutting off of waste materials which are not specifically described in the present invention all belong to the prior art.

[0068] Those skilled in the art will readily appreciate that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, combinations, replacements, improvements, etc. made within the spirit and principles of the present invention are included within the protection scope of the present invention.

Claims

1. A method for processing a hairless and earless circlip, characterized in that: The following steps are involved: Step 1: Punch the positioning hole and two small holes; Step 2: Pre-cutting and leveling, preliminarily separate the blanks through the pre-cutting and leveling die, and control the blanking gap Z within the thickness t of the stamping profile, t*5%≤Z≤t*8%, so as to level the blanks and reduce the collapse angle of the blanking section; Step 3: Positive and negative pressure flashing, the blank and the small holes on it are subjected to positive and negative pressure flashing treatment along the circumference through the positive and negative pressure flashing die, and the burrs are eliminated and the secondary leveling of the blank is completed by using the profiling design of the boss and the sink; Step 4: Blanking; Step 5: Cut off the scraps.

2. The method for processing a hairless and piercing-free circlip according to claim 1, characterized in that: The following steps are also included between step 1 and step 2: misfeed sensing detection, which automatically detects the accuracy of the feeding step and transmits the detection signal to the stamping equipment in real time, thereby realizing the automated coordinated operation of the continuous mold and the stamping equipment.

3. The method for processing hairless and piercing-free circlips according to claim 1, characterized in that: The pre-cutting and leveling die comprises a pre-cutting and leveling die and a pre-cutting and leveling punch. The pre-cutting and leveling die is provided with a die hole corresponding to the shape of the ear retaining spring, and the pre-cutting and leveling punch is provided with a pressure head corresponding to the shape of the ear retaining spring. The pre-cutting and leveling blanking gap Z = the outer diameter of the die hole - the outer diameter of the pressure head, t*5%≤Z≤t*8%, and t is the thickness of the stamping profile.

4. The method for processing hairless and piercing-free circlips according to claim 1, characterized in that: Pre-cut depth h1, 80% of the thickness of the stamping profile ≤ h1 ≤ the thickness of the stamping profile * 90%.

5. The method for processing hairless and piercing-free circlips according to claim 1, characterized in that: The positive and negative pressure flashing mold includes a positive and negative pressure flashing punch and a positive and negative pressure flashing die. The positive and negative pressure flashing punch has a first boss and a second boss corresponding to the shape of the ear retaining ring. The first boss is used to form the outer shape of the ear retaining ring, and the second boss is used to form the small hole on the ear retaining ring.

6. The method for processing hairless and piercing-free circlips according to claim 5, characterized in that: The height of the first boss is 0.6-0.8 times the thickness t of the stamped profile; the outer diameter of the first boss The value is the outer diameter of the ear circlip The height h3 of the second boss is 0.5-0.7 times the thickness t of the stamping profile.

7. The method for processing hairless and piercing-free circlips according to claim 6, characterized in that: The diameter of the second boss The value is the diameter of the hole on the ear card The taper of the second boss is 30°; the transition radius of the second boss is generally 0.2-0.5 mm.

8. The method for processing hairless and piercing-free circlips according to claim 7, characterized in that: The depth of the sink is 0.6-0.8 times the thickness t of the stamped profile; the diameter of the sink is The value is the outer diameter of the ear circlip The taper of the sinker is 30°; the transition radius of the sinker is 0.2-0.5mm.

9. The method for processing hairless and piercing-free circlips according to claim 1, characterized in that: The precutting and leveling mold also includes a precutting and leveling top material block, on which a top head corresponding to the shape of the ear spring is provided, and on the precutting and leveling concave mold a groove corresponding to the shape of the precutting and leveling top material block is provided, and the groove is connected to the mold hole.

10. The method for processing hairless and piercing-free circlips according to claim 1, characterized in that: The bosses and sinks of the positive and negative pressure flashing dies are designed in a contoured manner with tapers and rounded corners.

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