CN217370281U

CN217370281U - Double-taper cold heading pre-forming die

Info

Publication number: CN217370281U
Application number: CN202221435144.6U
Authority: CN
Inventors: 孙明; 唐宁波
Original assignee: Shaanxi Frant Auto Parts Co ltd
Current assignee: Shaanxi Frant Auto Parts Co ltd
Priority date: 2022-06-10
Filing date: 2022-06-10
Publication date: 2022-09-06
Anticipated expiration: 2032-06-10

Abstract

The utility model relates to the field of preformed dies, in particular to a double-taper cold heading preformed die which comprises a male die and a blank; a cone b and a cone a are sequentially arranged at the opening of the male die from outside to inside, the cone angle of the cone a is alpha, the cone angle of the cone b is beta, and the cone b and the cone a are coaxially arranged; the length and diameter of the billet are l and d, respectively. The utility model discloses can be used to the upset forging deformation than bigger product, application scope is wider, and has simple structure, and mould low in manufacturing cost waits advantage, still can reduce cold-heading forming station number simultaneously, better reduction the manufacturing cost of product.

Description

Double-taper cold heading pre-forming die

Technical Field

The utility model relates to a preforming mould field specifically is a bipyramid degree cold-heading preforming mould.

Background

Fig. 1 shows one of the most common forms of a pre-heading forming die for a head portion of a cold-headed product, which is a single-tapered structure. It is mainly used for the preforming of product head cold-heading. The method aims to improve the longitudinal stability of material deformation during final heading forming, reduce deformation resistance and avoid metal surface cracking. The preforming die with a general single-cone structure shown in FIG. 1 is only suitable for the middle preforming of the head of a product with the blank length-diameter ratio l/d less than or equal to 2.4, as shown in FIG. 2. If the length-diameter ratio l/d of the head forming blank of the product is more than 2.4, when a single-cone-shaped structure preforming die is used for forming, the phenomenon of longitudinal upsetting instability (bending) can be generated, so that the metal flow line of the head of the product is not distorted and folded, and the final upsetting forming quality of the head of the product cannot be ensured. Therefore, it is necessary to increase the number of times of preforming the head of the product or to perform the forming using a closed preforming die, which increases the cost of the die and the cost of manufacturing the product.

SUMMERY OF THE UTILITY MODEL

The utility model discloses the purpose is to the product head that exists among the background art when shaping blank draw ratio l d > 2.4 can't guarantee the problem of product head final upsetting shaping quality, provides a bipyramid degree cold-heading preforming mould.

The technical scheme of the utility model: a double-taper cold heading pre-forming die comprises a male die and a blank;

a cone b and a cone a are sequentially arranged at the opening of the male die from outside to inside, the cone angle of the cone a is alpha, the cone angle of the cone b is beta, and the cone b and the cone a are coaxially arranged; the length and diameter of the billet are l and d, respectively.

Preferably, the sum of the cone volumes of cones a and b is equal to 75% -85% of the volume of the head of the product, i.e. V _{Awl a} +V _{Awl b} ＝(0.75～0.85)V _{Head with a rotatable shaft} 。

Preferably, the volume of the cone a is designed according to the principle that the length-diameter ratio l/d of the blank is less than 2.8, the cone angle alpha is smaller than that of a conventional pre-forming die, and the cone angle alpha is designed according to the principle that the larger the length-diameter ratio of the blank is, the smaller the angle of the cone angle alpha is.

Preferably, the volume of the cone b depends on the total material length L of the head of the product _{General assembly} And 75-85% of the total volume of the blank, subtracting the material length of the cone a to calculate the volume of the blank, designing the cone according to the principle that the length-diameter ratio l/d is less than or equal to 2.4, wherein the cone angle beta is smaller than that of a conventional pre-forming die, and the cone angle beta is designed according to the principle that the larger the length-diameter ratio of the blank is, the smaller the angle of the cone angle beta is.

Preferably, the cone a and the cone b are arranged on the male die and the female die, respectively.

Compared with the prior art, the utility model discloses following profitable technological effect has: the double-taper pre-forming die can be used for pre-forming the head of a product with the maximum length-diameter ratio of a blank of 3.5 under the condition of not increasing a pre-forming station, and the pre-forming die with the structure has the advantages that in the longitudinal upsetting process, metal cannot generate longitudinal instability, and the metal flow line of the head of the product is smooth and free of distortion and folding, so that compared with a single-taper pre-forming die, the double-taper pre-forming die can be used for upsetting products with larger deformation ratio, the application range is wider, the double-taper pre-forming die has the advantages of simple structure, low die manufacturing cost and the like, meanwhile, the number of cold upsetting forming stations can be reduced, and the manufacturing cost of the product is well reduced.

Drawings

FIG. 1 is a schematic diagram of a prior art pre-forming die;

FIG. 2 is a schematic view of a blank construction;

FIG. 3 is a schematic structural diagram according to a first embodiment;

fig. 4 is a schematic structural diagram of the second embodiment.

Reference numerals: 1. a male die; 2. a blank; 3. a cone a; 4. a cone b; 5. and (5) forming a female die.

Detailed Description

Example one

As shown in fig. 3, the utility model provides a double-taper cold heading pre-forming die, which comprises a punch 1 and a blank 2;

a cone b4 and a cone a3 are sequentially arranged at the opening of the male die 1 from outside to inside, the cone angle of the cone a3 is alpha, the cone angle of the cone b4 is beta, and the cone b4 and the cone a3 are coaxially arranged; the length and diameter of the blank 2 are l and d, respectively. The cone volume of cones a3 and b4 is equal to 75% -85% of the product head volume, i.e. V _{Awl a} +V _{Awl b} ＝(0.75～0.85)V _Head . The volume of the cone a3 is designed according to the principle that the length-diameter ratio l/d of the blank 2 is less than 2.8, the cone angle alpha is smaller than that of a conventional preforming die, and the cone angle alpha is designed according to the principle that the larger the length-diameter ratio of the blank is, the smaller the angle of the cone angle alpha is. The volume of the cone b4 is determined by the total material length L of the head of the product _{General assembly} 75-85% of the total volume of the blank, subtracting the material length of the cone a3 to calculate the volume, designing the cone according to the principle that the length-diameter ratio l/d is less than or equal to 2.4, wherein the cone angle beta is smaller than that of a conventional pre-forming die, and the cone angle beta is designed according to the principle that the larger the length-diameter ratio of the blank is, the smaller the angle of the cone angle beta is.

In the embodiment, under the condition that a preforming station is not increased, the method can be used for preforming the head of a product with the maximum length-diameter ratio of 3.5 of a blank, and the preforming die with the structure has the advantages that in the longitudinal upsetting process, metal cannot generate longitudinal instability, and the metal flow line of the head of the product is smooth and free of distortion and folding.

Example two

As shown in fig. 4, compared with the first embodiment, the double-taper cold-heading pre-forming die of the present invention has a cone a3 and a cone b4 respectively disposed on the punch 1 and the die 5.

In the embodiment, the cone a3 and the cone b4 are respectively arranged between the punch 1 and the die 5, the die is particularly suitable for forming the middle part and the lower step of a rod-shaped product, and the longitudinal upset longitudinal instability phenomenon of longitudinal upsetting can not occur in the upsetting deformation process of the product blank 2 with the length-diameter ratio of 3 through the reasonable design of the cone a3 and the cone b 4.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited thereto, and various changes can be made without departing from the gist of the present invention within the scope of knowledge possessed by those skilled in the art.

Claims

1. A double-taper cold heading pre-forming die is characterized by comprising a male die (1) and a blank (2);

a cone b (4) and a cone a (3) are sequentially arranged at the opening of the male die (1) from outside to inside, the cone angle of the cone a (3) is alpha, the cone angle of the cone b (4) is beta, and the cone b (4) and the cone a (3) are coaxially arranged; the length and diameter of the blank (2) are l and d respectively.

2. A double-taper cold-heading pre-forming die as claimed in claim 1, wherein the sum of the taper volumes of the taper bodies a (3) and b (4) is equal to 75-85% of the volume of the head of the product, i.e., V _{Awl a} +V _{Awl b} ＝(0.75～0.85)V _{Head with a rotatable shaft} 。

3. A double taper cold heading pre-forming die as claimed in claim 1, wherein the volume of the taper a (3) is designed based on the principle that the length/d of the billet (2) is less than 2.8, and the taper angle α is smaller than that of the conventional pre-forming die, and the taper angle α is designed based on the principle that the larger the length/d of the billet is, the smaller the angle of the taper angle α is.

4. The double-taper cold-heading pre-forming die of claim 1, wherein the volume of the taper b (4) is based on the total product head material length L _{General (1)} And 75-85% of the total volume of the blank, subtracting the material length of the cone a (3) to calculate the volume of the blank, designing the cone according to the principle that the length-diameter ratio l/d is less than or equal to 2.4, wherein the cone angle beta is smaller than that of a conventional pre-forming die, and the cone angle beta is designed according to the principle that the larger the length-diameter ratio of the blank is, the smaller the angle of the cone angle beta is.

5. A double-taper cold-heading pre-forming die as claimed in claim 1, wherein the taper body a (3) and the taper body b (4) are provided on the punch (1) and the die (5), respectively.