CN111644506B - Female die assembly for punching thin annular tooth-shaped piece and preparation method thereof - Google Patents
Female die assembly for punching thin annular tooth-shaped piece and preparation method thereof Download PDFInfo
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- CN111644506B CN111644506B CN202010511387.2A CN202010511387A CN111644506B CN 111644506 B CN111644506 B CN 111644506B CN 202010511387 A CN202010511387 A CN 202010511387A CN 111644506 B CN111644506 B CN 111644506B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D28/00—Shaping by press-cutting; Perforating
- B21D28/02—Punching blanks or articles with or without obtaining scrap; Notching
- B21D28/14—Dies
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D37/00—Tools as parts of machines covered by this subclass
- B21D37/20—Making tools by operations not covered by a single other subclass
- B21D37/205—Making cutting tools
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Abstract
The invention discloses a female die component for punching a thin annular tooth-shaped piece and a preparation method thereof, relating to the field of fine blanking, wherein the method comprises the following steps: the method comprises the following steps: s1, turning a female die hoop, wherein the interference magnitude of the female die hoop relative to the female die core is 1.2-1.7 mm, the female die hoop and the female die core are concentric, the concentricity error is less than 0.1mm, and a tooth root circle female die cavity is formed in the female die core; s2, placing the female die hoop under the condition that the temperature is 700-900 ℃ and preserving heat for 1.5-3 hours, and then sleeving the female die hoop on the female die core. The female die assembly comprises a female die core, a female die hoop is sleeved on the female die core, a tooth root circle female die cavity is formed in the female die core, the female die core and the female die hoop are in interference fit, the interference magnitude is 1.2-1.7 mm, two end faces of the female die hoop are lower than two end faces of the female die core, namely two ends of the female die core protrude out of the end faces of the female die hoop. The invention can avoid the damage of the female die, improve the qualification rate of parts and reduce the production cost.
Description
Technical Field
The invention relates to the field of fine blanking, in particular to a female die assembly for punching a thin annular tooth-shaped piece and a preparation method thereof.
Background
At present, the application range of the die is wider and wider, the requirement on die materials is higher and higher, and particularly in a fine blanking die, a female die and a male die need to be made of imported high-strength steel materials so as to ensure the performance and the service life of the die.
The current mechanical products gradually tend to be miniaturized, corresponding parts are developed towards small, thin and light, thin annular parts are more and more in machining, thin annular tooth-shaped parts with the thickness of 1.5mm to 4mm are usually made of 65Mn or other spring steel after heat treatment, the hardness requirement is uniform, the dimensional tolerance requirement is strict, particularly, the dimensional tolerance zone of a root circle needs to be controlled to be 0.08mm, and the section brightness zone is controlled to be more than 75%.
The part is easy to deform in the heat treatment process, if tooth punching is carried out firstly and then heat treatment is carried out, the dimensional tolerance of a tooth root circle is difficult to guarantee, the qualification rate is low, the process is made to be fine punching after heat treatment, however, the hardness can reach 30-35 HRC after heat treatment, a convex-concave die and a concave die can generate large impact force during fine punching, meanwhile, the part is high in hardness and poor in ductility, the chamfer angle of a concave die cutting edge needs to be increased for guaranteeing the quality of a section after punching, when the chamfer angle of the concave die cutting edge is carried out, the lateral extrusion force of the concave die is large, the concave die can generate outward micro deformation during fine punching, the concave die core can easily generate cracks, the appearance size of the part can be increased, the concave die is damaged, the qualification rate of the part is reduced, the frequency of the updated concave die is increased, and the production cost is high.
Meanwhile, the existing female die is generally of an integral structure, most of the female die is made of CADIE (steel), and the cost is high.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a female die component for punching a thin annular tooth-shaped piece and a preparation method thereof, which can avoid the damage of a female die, improve the qualification rate of parts and reduce the production cost.
In order to achieve the above purposes, the technical scheme adopted by the invention is as follows:
a method of making a die assembly for punching thin annular teeth, comprising the steps of:
s1, lathing a female die hoop (2), wherein the interference magnitude of the female die hoop (2) relative to a female die core (1) is 1.2-1.7 mm, the female die hoop (2) and the female die core (1) are concentric, the concentricity error is less than 0.1mm, and a root circle female die cavity (3) is formed in the female die core (1);
s2, placing the female die hoop (2) at the temperature of 700-900 ℃ and preserving heat for 1.5-3 hours, and then sleeving the female die hoop (2) on the female die core (1).
Further, step S2 specifically includes the following steps:
placing the concave mould hoop (2) under the condition that the temperature is 700-900 ℃ for heat preservation for 1.5-3 hours, simultaneously placing the concave mould core (1) on a flat plate, placing a plurality of gaskets with the height of 2-4 mm on the outer side of the concave mould core (1), sleeving the heated concave mould hoop (2) on the concave mould core (1), and enabling the bottom end of the concave mould hoop (2) to be abutted against the gaskets for rapidly cooling by tap water.
Further, step S3 is followed by the following steps: and chamfering the cutting edge of the concave mold core (1), wherein the chamfer angle is 30 degrees according to 0.3 mm.
Furthermore, the interference of the female die hoop (2) relative to the female die core (1) is 1.5 mm.
Further, in the step S2, the temperature of the female mold hoop (2) is 700 ℃ and the time is 2 h.
The utility model provides a die subassembly that is used for punching press thin ring tooth spare that above-mentioned method was made, includes female mold core (1), female mold hoop (2) have been cup jointed on female mold core (1), be root circle die cavity (3) in female mold core (1), female mold core (1) and female mold hoop (2) interference fit, and the magnitude of interference is 1.2 ~ 1.7mm, female mold core (1) and female mold hoop (2) set up with one heart, and the concentricity error is less than 0.1mm, the both ends face of female mold hoop (2) is less than the both ends face of female mold core (1), promptly the both ends protrusion of female mold core (1) is outside the terminal surface of female mold hoop (2).
Furthermore, the interference magnitude between the concave mold core (1) and the concave mold hoop (2) is 1.5 mm.
Furthermore, the female die core (1) is made of CADIE materials, and the female die hoop (2) is made of 45# steel.
Furthermore, the chamfer angle of the cutting edge on the concave mold core (1) is 0.3mm and 30-degree bevel angle.
Compared with the prior art, the invention has the advantages that:
(1) the female die assembly for stamping the thin circular ring tooth-shaped piece comprises a female die core, wherein a female die hoop is sleeved on the female die core, a tooth root circle female die cavity is formed in the female die core, the female die core is in interference fit with the female die hoop, and the interference magnitude is 1.2-1.7 mm, so that the female die hoop has a pretightening force on the female die core, the female die core is prevented from being expanded due to heat under the condition of being heated and deforming outwards slightly, the female die core is prevented from being damaged, the service life of the die can be ensured, and the use cost is reduced; the concave die core and the concave die hoop are concentrically arranged, the concentricity error is smaller than 0.1mm, the lateral compression of the outer wall of the concave die core is uniform, the concave die core is prevented from generating outward force when the concave die core is subjected to fine blanking to cause the enlargement of a tooth root circle concave die cavity, the overall dimension of a part is further caused to deform, the overall dimension of the part can be effectively ensured, and the qualification rate of the part is improved.
(2) According to the female die assembly for punching the thin annular tooth-shaped piece, two end faces of the female die hoop are lower than two end faces of the female die core, namely two ends of the female die core protrude out of the end faces of the female die hoop, so that the female die assembly can be conveniently clamped in subsequent finish machining, and meanwhile, a reference surface is reserved for surface correction; the concave die core is made of a CADIE material, the concave die hoop is made of 45# steel, the cost of the conventional integral concave die is high due to the high cost of the CADIE material, the concave die component in the embodiment of the invention only uses the CADIE material for the concave die core, and the cost of the concave die component is effectively reduced, and in the embodiment, the cost of the concave die component is only 1/2 of the cost of the integral concave die.
(3) The preparation method of the female die component for punching the thin annular tooth-shaped piece comprises the steps of machining a female die hoop by a lathe, wherein the interference magnitude of the female die hoop relative to a female die core is 1.2-1.7 mm, the female die hoop and the female die core are concentric, the concentricity error is less than 0.1mm, and a tooth root circle female die cavity is arranged in the female die core; and (3) placing the female die hoop under the condition that the temperature is 700-900 ℃ for heat preservation for 1.5-3 hours, and then sleeving the female die hoop on the female die core.
Drawings
FIG. 1 is a schematic diagram of a die assembly for punching thin annular teeth in an embodiment of the present invention;
FIG. 2 is a schematic view of the structure of the female die assembly in cooperation with the thin annular toothed element;
FIG. 3 is a schematic view of the structure of the female die assembly in cooperation with the thin annular toothed element.
In the figure: 1-concave mould core, 2-concave mould hoop and 3-tooth root round concave mould cavity.
Detailed Description
Embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.
Referring to fig. 1, the embodiment of the invention provides a female die assembly for punching a thin circular ring tooth-shaped member, which comprises a female die core 1, wherein a female die hoop 2 is sleeved on the female die core 1, a tooth root circle female die cavity 3 is arranged in the female die core 1, the female die core 1 is in interference fit with the female die hoop 2, and the interference magnitude is 1.2-1.7 mm (optimally 1.5mm), so that the female die hoop 2 has a pretightening force on the female die core 1, the female die core 1 and the female die hoop 2 are concentrically arranged, and the concentricity error is less than 0.1mm, so that the outer wall of the female die core 1 is uniformly pressed in the lateral direction.
The thickness of the female die hoop 2 is 50mm, the thickness of the female die core 1 is 55mm, and the two end faces of the female die hoop 2 are lower than the two end faces of the female die core 1, namely the two ends of the female die core 1 protrude out of the end faces of the female die hoop 2, so that the female die assembly can be conveniently clamped in subsequent finish machining, and meanwhile, a reference surface is reserved for surface correction.
The concave die assembly in the embodiment of the invention only uses the CADIE material for the concave die core 1, so that the cost of the concave die assembly is effectively reduced, and in the embodiment, the cost of the concave die assembly is only 1/2 of the cost of the integral concave die.
When the female die component of the embodiment of the invention is used for punching a thin circular ring tooth-shaped piece, the bright band of the section of the part is more than or equal to 80 percent,
the invention also provides a preparation method of the female die component for punching the thin annular tooth piece, which comprises the following steps:
s1, turning the female die hoop 2, wherein the interference magnitude of the female die hoop 2 relative to the female die core 1 is larger than or equal to 1.2-1.7 mm (optimally 1.5mm), the female die core 1 and the female die hoop 2 are arranged concentrically, and the concentricity error is smaller than 0.1 mm.
S2, performing hot hooping on the female die hoop 2
After a female die hoop 2 with the interference magnitude of 1.5mm is placed under the condition that the temperature is 700-900 ℃ and is kept warm for 1.5-3 hours (the optimal condition is that the temperature is kept warm for 2 hours under the condition of 800 ℃), meanwhile, a female die core 1 is placed on a flat plate, a plurality of gaskets with the height of 2-4 mm are placed on the outer side of the female die core 1, the heated female die hoop 2 is sleeved on the female die core 1, the bottom end of the female die hoop 2 is abutted against the gaskets, tap water is used for rapidly cooling, and the female die is guaranteed not to be annealed to reduce the hardness of the outer side.
And S3, chamfering the cutting edge of the concave mold core 1, and chamfering by 30 degrees according to 0.3 mm.
In preparing the die assemblies, the following comparative tests were also performed:
comparative example
Placing the female die hoop 2 with the interference magnitude of 1mm at the temperature of 600 ℃ for heat preservation for 2 hours, sleeving the heated female die hoop 2 on the female die core 1, measuring the hardness of the female die core 1, wherein the hardness of all points is HRC58-60 and is basically consistent with that before hot hooping, the cutting edge of the female die core 1 is chamfered by 30 degrees at an oblique angle of 0.2mm, the appearance size of the part after trial punching is qualified, and the section of the bright belt is 60 percent and cannot meet the quality requirement; the chamfer angle of the cutting edge of the concave mold core 1 is increased to 0.3mm, the brightness after punching is obviously improved to 80 percent, and the requirement is met; however, the size of the root circle die cavity 3 is: the diameter is 250.5mm, the tolerance requirement is 0.005mm, and the composite fine blanking process characteristic determines the external dimension of the fine blanking part determined by the cavity of the female die, and the size requirement of the root circle of the part is as follows: the diameter is 250.5mm, the tolerance requirement is 0.08mm, the actually measured tooth root circle size of the part is 250.60 mm-250.65 mm, the above difference is 0.02 mm-0.07 mm, and the size of the obtained part does not meet the requirement.
Therefore, when high-hardness materials are subjected to fine punching, the section bright zone of the part can be improved by increasing the cutting edge chamfer of the concave die core 1; after the female die hoop 2 with the interference magnitude of 1mm is matched with the female die core 1, the strength of the female die component is insufficient, and the cavity of the female die core 1 expands outwards during fine blanking, so that the size of the root circle is expanded by 0.12-0.15 mm, and the size of a part does not meet the requirement.
Example 1
In order to increase the strength of the female die assembly, the interference magnitude of the female die hoop 2 is adjusted to be 1.5mm, the temperature is kept at 800 ℃ for two hours, the interference magnitude is increased to increase the extrusion force of the female die hoop 2 on the female die core 1, the expansion amount of the female die core 1 during fine blanking is reduced, the temperature is increased to heat the female die hoop 2 to increase the expansion amount of the inner hole of the female die, and the female die hoop 2 can be conveniently placed into a female die.
The heated female die hoop 2 is sleeved on the female die core 1, the hardness of the female die core 1 is measured, the hardness of the edge of the hot hoop is reduced within 3mm and is HRC45-55, the rest part is HRC58-60, therefore, the hardness of the female die core 1 is not influenced by a hot hoop method, the cutting edge of a female die is chamfered by 30 degrees according to 0.3mm, the bright zone of the cross section of a part after punching is 80 percent, the technical requirement is met, the actual measurement of the size of a root circle with the diameter of 250.5mm and the tolerance requirement of 0.08mm is 250.52 mm-250.54 mm, the requirements are met, and the female die assembly prepared by adopting the comparative example is used for punching 30 parts, and is completely qualified after measurement and has stable size.
Example 2
The interference magnitude is adjusted to be 1.2, the heat preservation time is adjusted to be 700 ℃, the heat preservation time is 3 hours, other conditions are the same as the embodiment 1, the bright zone of the cross section of the part after the pilot punching is 81 percent,
the actual measurement of the size of the root circle with the diameter of 250.5mm and the tolerance requirement of 0.08mm is 250.51-250.55 mm, the practical measurement meets the requirement, and 30 pieces of die assemblies prepared by adopting the comparative example are all qualified after measurement and have stable size.
Example 3
The interference magnitude is adjusted to be 1.7, the heat preservation time is adjusted to be 900 ℃, the heat preservation time is 1.5 hours, other conditions are the same as the embodiment 1, the bright zone of the cross section of the part after the pilot punching is 81.5%, the diameter is set to be 250.5mm, the actual measurement of the size of the tooth root circle with the tolerance requirement of 0.08mm is 250.50 mm-250.53 mm, the requirements are met, and 30 parts of the female die assembly prepared by adopting the comparative example are completely qualified after the measurement and have stable size.
The present invention is not limited to the above-mentioned preferred embodiments, and any other products in various forms can be obtained by anyone with the teaching of the present invention, but any changes in the shape or structure thereof, which have the same or similar technical solutions as the present invention, are within the protection scope.
Claims (7)
1. A preparation method of a female die component for punching thin annular teeth is characterized in that: the method comprises the following steps:
s1, lathing a female die hoop (2), wherein the interference magnitude of the female die hoop (2) relative to a female die core (1) is 1.2-1.7 mm, the female die hoop (2) and the female die core (1) are concentric, the concentricity error is less than 0.1mm, and a root circle female die cavity (3) is formed in the female die core (1);
s2, placing the female die hoop (2) at 700-900 ℃ for heat preservation for 1.5-3 hours, meanwhile, placing the female die core (1) on a flat plate, placing a plurality of gaskets with the height of 2-4 mm on the outer side of the female die core (1), sleeving the heated female die hoop (2) on the female die core (1), enabling the bottom end of the female die hoop (2) to be abutted against the gaskets, and rapidly cooling with tap water;
s3, chamfering the cutting edge of the concave mold core (1), and chamfering the cutting edge by 30 degrees according to 0.3 mm.
2. A method of making a die assembly for punching thin annular teeth according to claim 1, wherein: the interference magnitude of the female die hoop (2) relative to the female die core (1) is 1.5 mm.
3. A method of making a die assembly for punching thin annular teeth according to claim 1, wherein: in the step S2, the heat preservation temperature of the female die hoop (2) is 700 ℃, and the time is 2 h.
4. A die assembly for punching thin annular teeth made by the method of any one of claims 1 to 3, characterized by: including concave mould core (1), concave mould hoop (2) have been cup jointed on concave mould core (1), be tooth root circle die cavity (3) in concave mould core (1), concave mould core (1) and concave mould hoop (2) interference fit, and the magnitude of interference is 1.2 ~ 1.7mm, concave mould core (1) and concave mould hoop (2) set up with one heart, and the concentricity error is less than 0.1mm, the both ends face of concave mould hoop (2) is less than the both ends face of concave mould core (1), promptly the both ends protrusion of concave mould core (1) is outside the terminal surface of concave mould hoop (2).
5. A die assembly for punching thin annular teeth according to claim 4, wherein: the interference magnitude of the concave mold core (1) and the concave mold hoop (2) is 1.5 mm.
6. A die assembly for punching thin annular teeth according to claim 4, wherein: the female mold core (1) is made of CADIE materials, and the female mold hoop (2) is made of 45# steel.
7. A die assembly for punching thin annular teeth according to claim 4, wherein: the chamfer angle of the cutting edge on the concave mold core (1) is a bevel angle of 0.3mm and 30 degrees.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010511387.2A CN111644506B (en) | 2020-06-08 | 2020-06-08 | Female die assembly for punching thin annular tooth-shaped piece and preparation method thereof |
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| CN202010511387.2A CN111644506B (en) | 2020-06-08 | 2020-06-08 | Female die assembly for punching thin annular tooth-shaped piece and preparation method thereof |
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| CN111644506B true CN111644506B (en) | 2021-11-23 |
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| CN112387869B (en) * | 2020-10-28 | 2022-11-01 | 东风汽车零部件(集团)有限公司通用铸锻分公司 | Continuous stamping die of inside and outside sawtooth lock washer |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204449016U (en) * | 2014-12-26 | 2015-07-08 | 广东骏汇汽车科技股份有限公司 | Plate hot jacket gear ring plate structure in fine blanking die |
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| CH475805A (en) * | 1967-06-05 | 1969-07-31 | Feintool Ag | Fine cut punching tool |
| CN103464570A (en) * | 2012-06-05 | 2013-12-25 | 吴正伟 | Serrate wear-proof detachable shaving die |
| CN102764786A (en) * | 2012-08-01 | 2012-11-07 | 郑州机械研究所 | Method for prolonging service life of cold finishing die of shaft parts |
| CN203621129U (en) * | 2013-10-25 | 2014-06-04 | 盐城金刚星齿轮厂 | Once processing die of internal and external teeth of gear |
| CN203751082U (en) * | 2014-01-17 | 2014-08-06 | 福州锐新金属有限公司 | Fine blanking die for steel back of brake for improving dimensional stability and concave die service life |
| CN105855354A (en) * | 2016-05-16 | 2016-08-17 | 常州大学 | Chain wheel blanking forming method and device |
| CN207086657U (en) * | 2017-08-15 | 2018-03-13 | 聊城市博源节能科技有限公司 | The shaping fine blanking die of Car Change-speed Gear Box Binding Gear |
| CN109940356A (en) * | 2019-03-11 | 2019-06-28 | 深圳航空标准件有限公司 | The manufacturing procedure of double trimming formers and its double trimming formers |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN204449016U (en) * | 2014-12-26 | 2015-07-08 | 广东骏汇汽车科技股份有限公司 | Plate hot jacket gear ring plate structure in fine blanking die |
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Denomination of invention: A female die assembly for stamping thin ring gear parts and its preparation method Effective date of registration: 20220629 Granted publication date: 20211123 Pledgee: Bank of China Limited Wuhan Qingshan sub branch Pledgor: WUHAN HUAXIA FINE-BLANKING TECHNOLOGY CO.,LTD. Registration number: Y2022420000207 |