CN114054659A

CN114054659A - Twill forming die structure of riveting nut

Info

Publication number: CN114054659A
Application number: CN202010749467.1A
Authority: CN
Inventors: 郭明哲
Original assignee: Weiying Industrial Co ltd
Current assignee: Weiying Industrial Co ltd
Priority date: 2020-07-30
Filing date: 2020-07-30
Publication date: 2022-02-18

Abstract

A cross grain forming die structure of a riveting nut comprises a forging die seat, a 1 st forging die, a 2 nd forging die and a limiting piece; the forging die base is provided with a die cavity, and the die cavity is provided with a section of threaded part; the 1 st forging mold is provided with a nut mold cavity and a forging mold cavity, the nut mold cavity penetrates through the forging mold cavity, and an inclined shoulder part is formed between the nut mold cavity and the forging mold cavity; the 2 nd forging die is provided with an abutting inclined surface at the front end, an inclined line part and a through guide hole are arranged on the inner surface, and the inclined line part is composed of a plurality of inclined convex teeth; the 2 nd forging die is placed in the forging die cavity and is placed into the die cavity together with the 1 st forging die, the limit piece is limited in the die cavity, and the 2 nd forging die and the forging die cavity are in low-friction contact. The flange of the nut blank is directly compression-molded into a twill convex tooth at the twill part of the 2 nd forging die, and the 2 nd forging die easily rotates along with the inclination of the twill convex tooth of the twill part during die stripping, so that the flange is smoothly stripped from the 2 nd forging die.

Description

Twill forming die structure of riveting nut

Technical Field

The present invention relates to a mold structure for forming a rivet nut, and more particularly, to a mold structure for forming a rivet nut, which can directly form a spiral-shaped protrusion on a nut forming machine during a continuous forming process of the rivet nut.

Background

The clinch nut is a coupling member that is press-riveted and then coupled to an anchor hole of a metal thin plate to provide screw fastening of a bolt. Referring to fig. 1, a conventional clinch nut 10 with a helical-toothed portion is shown, the clinch nut 10 mainly includes a nut body 11 and a flange 12, a threaded hole 13 with an internal thread penetrates the nut body 11 and the flange 12, wherein the flange 12 has a helical-toothed portion 14 arranged at equal intervals around an outer surface thereof, the helical-toothed portion 14 is protruded from an outer surface of the flange 12 in an angular inclined manner, different from the conventional axial parallel-toothed design; the inclined-grain convex teeth 14 can improve the friction force between the riveting nut and the plate, and have the functions of preventing the riveting nut from rotating and preventing the riveting nut from axially disengaging.

The known production process of the riveting nut is mainly matched with a nut forming machine commonly used in the industry, a series of dies are arranged on the nut forming machine, a blank is formed into a nut prototype with a flange appearance after being subjected to a plurality of forging and pressing shaping procedures, however, the forging and pressing action of the nut forming machine is almost axial stroke, so that the nut forming machine is only suitable for processing the riveting nut with straight-line convex teeth, if the inclined-grain convex teeth are formed by forging and pressing the traditional dies in the known nut forming machine, the inclined-grain convex teeth are naturally limited by the appearance interference between the inclined-grain convex teeth and the dies, the films are difficult to directly peel off, the processed objects or the dies are easy to damage under the forced peeling, and the forming convex teeth in the industry are mainly formed through a knurling process at present.

As can be seen from the above description, the conventional twill-toothed riveting nut cannot be directly formed by the existing nut forming machine, and requires 2 times of knurling process, so that the overall production efficiency is greatly reduced, and the production capacity is greatly affected. Therefore, in order to improve the forming efficiency of the twill teeth, the related manufacturers need to discuss the improvement of better processing procedure or mold equipment.

Disclosure of Invention

The main objective of the present invention is to provide a die structure for forming a diagonal of a riveting nut, which can directly form a diagonal convex tooth portion of the riveting nut on a nut forming machine, thereby effectively improving the production efficiency and greatly increasing the production of the diagonal convex tooth riveting nut.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows: the utility model provides a twill forming die structure of riveting nut, its characterized in that, it contains: a forging die base, wherein the forging die base is provided with a die cavity which is provided with a section of threaded part; a 1 st forging die, wherein the 1 st forging die is provided with a nut die cavity and a forging die cavity, the nut die cavity penetrates through the forging die cavity, and an inclined shoulder part is formed between the nut die cavity and the forging die cavity; and a 2 nd forging die, the 2 nd forging die body is the hollow cylinder configuration, the 2 nd forging die front end has resisting the inclined plane, the inner face is made a twill portion and pierced through guide hole, the twill portion is formed by several oblique convex teeth; the 2 nd forging die is arranged in the forging die cavity and is arranged in the die cavity together with the 1 st forging die, a limiting piece is screwed on the threaded part of the forging die seat, the 1 st forging die and the 2 nd forging die are limited in the die cavity in a matching way, and the 2 nd forging die and the forging die cavity form low-friction contact.

The inclination of the abutting inclined surface corresponds to that of the inclined shoulder.

The outer wall of the 2 nd forging die is not contacted with the inner wall of the forging die cavity.

The overall height of the 2 nd forging die is more than 99.5 percent of the depth of the forging die cavity and less than the depth of the forging die cavity.

The inclination angle of the oblique convex teeth is between 35 and 45 degrees.

The flange of the nut blank of the invention can be directly formed into the twill convex tooth by compression molding at the twill part of the 2 nd forging die, and when the die is removed, the 2 nd forging die can easily rotate along with the inclination of the oblique convex tooth of the twill part because the 2 nd forging die is in low friction contact with the forging die cavity, and finally the flange can be smoothly released from the 2 nd forging die. In view of the above, this creation has broken through the disappearance that riveting nut's twill dogtooth can't directly accomplish processing at known nut processing machine, more can be because of omitting 2 processing of annular knurl processing procedure, and then promote twill riveting nut's production capacity by a wide margin.

Drawings

Figure 1 is a perspective view of a known twill clinch nut.

FIG. 2 is an exploded view of the preferred embodiment of the present invention.

FIG. 3 is a schematic cross-sectional view of the structure of the preferred embodiment of the present invention.

Figure 4 is a schematic view of extruding a nut stock having a flange into a chamfered portion.

FIG. 5 is a schematic view of the 2 nd forging die operating when the screw cap with the formed thread portion exits the cavity.

Description of the symbols:

10. riveting nut

11. Nut body

12. Flange

13. Screw hole

14. Convex tooth of twill

20. Forging die seat

21. Die cavity

22. Screw thread part

23. Position limiting piece

30. 1 st forging die

31. Forging die cavity

32. Nut mould cavity

33. Oblique shoulder

40. 2 nd forging die

41. Inclined plane

42. Twill portion

421. Oblique convex tooth

43. Guide hole

50. Nut blank

51. Flange

52. Convex tooth of twill

60a, front punch

60b, a rear punch.

Detailed Description

In order to fully describe the structural features, technical contents, effects and other features of the present invention, the following detailed description of the preferred embodiments is given with reference to the accompanying drawings.

First, referring to fig. 2, a preferred embodiment of the invention is disclosed, which is a cross-grain forming die structure of a rivet nut, and is mainly composed of a forging die base 20, a 1 st forging die 30 and a 2 nd forging die 40; the forging die base 20 is provided with a die cavity 21 for accommodating the 1 st forging die 30 and the 2 nd forging die 40, the 1 st forging die 30 is provided with a forging die cavity 31 for accommodating the 2 nd forging die 40, and the 2 nd forging die 40 is similar to the forging die cavity 31 in appearance but preset with a dimensional tolerance; a section of thread portion 22 is disposed in the cavity 21 near the open end, and a stopper 23 is screwed on the thread portion 22 to limit the 1 st forging die 30 and the 2 nd forging die 40 in the cavity 21.

Referring to fig. 3, which is a schematic sectional view of the cross-section of the riveting nut twill forming mold structure of fig. 2, the 1 st forging die 30 has a forging die cavity 31 and a nut die cavity 32, the nut die cavity 32 penetrates through the forging die cavity 31, and a slant shoulder 33 is formed between the two. Referring to fig. 4, the main body of the 2 nd forging die 40 is a hollow cylinder, the front end of the 2 nd forging die 40 is provided with a slope 41 corresponding to the slope of the slope shoulder 33, the inner surface of the 2 nd forging die 40 is provided with a thread portion 42 and a through guide hole 43, the thread portion 42 is a portion for forming a thread projection on the flange of the nut blank, the thread portion 42 is formed by a plurality of thread projections 421, and the angle of inclination of the thread projections 421 is between 35 ° and 45 °; the diameter of the outer wall of the 2 nd forging die 40 does not correspond to the inner wall of the forging die cavity 31, and the embodiment is explained by narrowing the diameter from the abutting inclined surface 41 to the rear end by 5 degrees, that is, the outer wall of the 2 nd forging die 40 does not correspond to the inner wall of the forging die cavity 31 in shape and does not contact with each other, and in addition, the whole height of the 2 nd forging die 40 is smaller than the depth of the forging die cavity 31 and larger than 99.5% of the depth of the forging die cavity 31, so that the 2 nd forging die 40 and the forging die cavity 31 form low friction joint.

Referring to FIG. 4, a forging operation according to a preferred embodiment of the present invention is shown. The forging process of the nut processing machine is mainly divided into two stages, namely a die stamping stage for simultaneously extruding a nut blank by a front punch and a rear punch, and a die withdrawing stage for pushing the nut blank out of a forming die cavity by a rear filling head; in this figure, there is shown a schematic view of the die of the present invention for extruding the nut blank 50 in the die stage, wherein the nut blank 50 is placed in the nut cavity 32 by the feeding mechanism before the punch is activated, and the nut blank 50 is extruded by the front punch 60a and the rear punch 60b, so that the flange 51 is compression molded to form the twill teeth 52 at the 2 nd die 40.

Finally, referring to fig. 5, a schematic diagram is shown for illustrating how the preferred embodiment of the present invention successfully performs the mold stripping operation. In the process, when the nut blank 50 is not rotated, the 2 nd forging die 40 is in low friction contact with the forging die cavity 31, so that the 2 nd forging die 40 can easily rotate along with the inclined teeth of the inclined thread part 42 as a whole, and finally the flange 51 of the nut blank 50 is smoothly released from the 2 nd forging die 40, thereby achieving the main purpose of directly forming and riveting the inclined teeth of the nut on the nut processing machine and avoiding damaging the inclined teeth 52 of the nut blank and the inclined thread part of the die.

After the above embodiments are described, it can be easily understood that the present invention has at least the following advantages: 1. the invention discloses a twill forming die structure of a riveting nut, which breaks through the defect that the conventional nut processing machine cannot smoothly complete the processing of twill convex teeth. 2. The application of the invention omits the known knurling process of the twill riveting nut for 2 times of processing, actually shortens the processing procedure and time and greatly improves the production of the twill riveting nut.

In summary, the invention of the twill forming mold structure of the riveting nut has achieved the default purpose and met the industrial requirement, and the patent application is proposed according to law. However, although the invention has been described with reference to the preferred embodiments, it is to be understood that the invention is not limited to the precise arrangements and instrumentalities shown, which are consistent with the spirit and scope of the invention, but rather are to be construed in breadth and scope in accordance with the appended claims.

Claims

1. The utility model provides a twill forming die structure of riveting nut, its characterized in that, it contains:

a forging die base, wherein the forging die base is provided with a die cavity which is provided with a section of threaded part;

a 1 st forging die, wherein the 1 st forging die is provided with a nut die cavity and a forging die cavity, the nut die cavity penetrates through the forging die cavity, and an inclined shoulder part is formed between the nut die cavity and the forging die cavity; and

a 2 nd forging die, the 2 nd forging die main part is the hollow cylinder configuration, 2 nd forging die front end have support inclined plane, the inside has a twill portion and feed hole that pierces through, the twill portion is formed by several oblique convex teeth;

the 2 nd forging die is arranged in the forging die cavity and is arranged in the die cavity together with the 1 st forging die, a limiting piece is screwed on the threaded part of the forging die seat, the 1 st forging die and the 2 nd forging die are limited in the die cavity in a matching way, and the 2 nd forging die and the forging die cavity form low-friction contact.

2. The rivet nut twill forming die structure defined in claim 1, wherein said abutment ramp corresponds to the slope of the beveled shoulder.

3. The clinch nut twill forming die structure of claim 1, wherein the 2 nd die outer wall is not in contact with the die cavity inner wall.

4. The rivet nut twill forming die structure of claim 1, wherein the 2 nd die overall height is greater than 99.5% of the die cavity depth and less than the die cavity depth.

5. The rivet nut twill forming die structure of claim 1, wherein the angle of inclination of the oblique teeth is between 35 ° and 45 °.