CN112496222A

CN112496222A - Cold-heading device, nut and clamping jaw assembly that nut was used

Info

Publication number: CN112496222A
Application number: CN202011334528.4A
Authority: CN
Inventors: 潘家云; 段森月
Original assignee: Penn Engineering Automotive Fasteners Kunshan Co ltd
Current assignee: Penn Engineering Automotive Fasteners Kunshan Co ltd
Priority date: 2020-11-25
Filing date: 2020-11-25
Publication date: 2021-03-16

Abstract

The invention discloses a cold heading device for a nut, the nut and a clamping jaw assembly, wherein the nut comprises a nut body and a flange sleeved on the nut body, a preset distance is formed between the end part of one end of the nut body and the end part of one end of the flange close to the nut body, the preset distance is not more than 5mm, the cold heading device comprises a first die, a second die, a third die, a fourth die, a fifth die and a clamping jaw assembly for moving a workpiece between the fourth die and the fifth die, wherein the clamping jaw assembly at least comprises two clamping jaws which are oppositely arranged, each clamping jaw comprises a first clamping part which is attached to the side surface of a flange, the second clamp part is attached to the side face of the preset part, a first clamp space matched with the flange is formed between the first clamp parts, a second clamp space matched with the preset part is formed between the second clamp parts, and the nut is formed by cold heading through the cold heading device. Through using this cold-heading device to simplify nut course of working, improve machining efficiency.

Description

Cold-heading device, nut and clamping jaw assembly that nut was used

Technical Field

The invention relates to the field of fastener manufacturing, in particular to a cold heading device for a nut, the nut and a clamping jaw assembly.

Background

The cold heading process is one of the few new processes for non-cutting metal press working. The method is a processing method which utilizes the plastic deformation generated by metal under the action of external force and redistributes and transfers the volume of the metal by means of a die so as to form the required part or blank. The cold heading process is most suitable for producing standard fasteners such as bolts, screws, nuts, rivets, pins, and the like.

However, when some short parts are machined by using the existing cold heading process, because the parts are too short, for example, when the size of the parts exposed out of the die is 4 mm-5 mm, the existing clamps cannot clamp the parts, so that the clamps in the existing cold heading machine cannot transfer the machined parts, the product needs to be completed by two steps of the cold heading process and the machining process, and the machining efficiency of the product is seriously reduced.

Disclosure of Invention

In order to overcome the defects in the prior art, the embodiment of the invention provides the cold heading device for the nut, the nut can be processed by cold heading by using the cold heading device, the processing steps are reduced, and the processing efficiency is improved.

In order to achieve the purpose, the invention adopts the technical scheme that: a cold heading device for a nut is disclosed, wherein the nut comprises a nut body and a flange sleeved on the nut body, a preset distance is formed between the end part of one end of the nut body and the end part of one end, close to the nut body, of the flange, and the preset distance is not more than 5 mm; the cold heading device includes:

a first die for forming a first portion of a pre-set blank into a straight section;

a second die for extruding a first bore within the straight section;

a third die for extruding a second bore within a second portion of the pre-set billet;

a fourth mold for molding a flange between the straight section and the second portion and forming a preset portion having the preset distance between an end of the second portion and an end of the flange adjacent to the second portion;

the fifth die is used for separating the waste material positioned between the first inner hole and the second inner hole from the machined part, so that the first inner hole is communicated with the second inner hole to form a central hole;

the clamping jaw assembly is used for moving the workpiece and comprises at least two oppositely arranged clamping jaws, each clamping jaw comprises a first clamping part and a second clamping part, the first clamping part is attached to the side face of the flange, the second clamping part is attached to the side face of the preset part, a first clamping space matched with the flange is formed between the first clamping parts, and a second clamping space matched with the preset part is formed between the second clamping parts.

In the above technical solution, when the workpiece in the fourth mold is in a demolding state, the first clamping space is opposite to the main mold cavity of the fourth mold, the preset portion is located in the first clamping space, and a part of the flange is attached to the first clamping portion.

In the technical scheme, the first clamping part and the second clamping part are both arc-shaped surfaces, and when the clamping part is in a clamping state, the arc-shaped surfaces are in surface contact with the side surfaces of the machined part.

In the technical scheme, the clamping jaws extend along the horizontal direction.

In the above technical scheme, the first clamping portion and the second clamping portion are inwardly recessed to form an avoiding portion, and the width of the avoiding portion is smaller than that of the flange.

In the above technical solution, the first mold, the second mold, the third mold, the fourth mold and the fifth mold each include a main mold and a punch mold that are correspondingly disposed;

the main die comprises a main die shell, a main die cushion block, a main die ejector pin and a main die core, wherein the main die cushion block, the main die ejector pin and the main die core are arranged in the main die shell;

the die comprises a die stamping shell, a die stamping cushion block and a die stamping thimble which are arranged in the die stamping shell, one end of the die stamping thimble is connected with the die stamping cushion block, and the other end of the die stamping thimble penetrates out of the die stamping shell to be opposite to the main die cavity.

In the above technical scheme, the main mold of the second mold, the third mold and the fourth mold further comprises a push-out thimble, the push-out thimble penetrates through the main mold cushion block, the top end of the push-out thimble abuts against the bottom of a push tube cushion block sleeved on the main mold thimble, a push tube sleeved on the main mold thimble abuts against the top of the push tube cushion block, and the top end of the push tube abuts against the end of the straight section.

In the above technical solution, a channel communicated with the inside of the push pipe is formed in the main die of the fifth die, and the waste material can slide down along the channel under the punching of the punch die thimble.

The utility model provides a nut, includes nut body and cover and establishes flange on the nut body, the internal centre bore that is including of nut body, the tip of the one end of nut body with the flange close on in form the distance of predetermineeing between the tip of the one end of nut body, it is not more than 5mm to predetermine the distance, should the nut is whole to be formed by the cold-heading.

A jaw assembly for use in moving a workpiece in a cold forging apparatus as set forth in claim 1, wherein: the clamping jaw comprises two opposite clamping jaws, a clamping space matched with the workpiece is formed between the opposite clamping jaws, and when the workpiece is moved, the clamping jaws are attached to the side forming surfaces of the workpiece.

Due to the application of the technical scheme, compared with the prior art, the invention has the following advantages:

1. the cold heading device comprises a first die, a second die, a third die, a fourth die and a fifth die, a clamping jaw assembly used for moving a workpiece is arranged between the fourth die and the fifth die, and the clamping jaw assembly can move a nut with a preset distance not more than 5mm, so that the forming of a central hole in the nut can be completed by cold heading, the steps of subsequent machining are reduced, and the machining efficiency is improved.

In order to make the aforementioned and other objects, features and advantages of the invention comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic view of a nut according to the present invention;

FIG. 2 is a schematic view of the cold forging apparatus according to the present invention;

FIG. 3 is a schematic view of a nut forming process of the present invention;

FIG. 4 is a schematic view of a workpiece in a fourth mold in a demolding state according to the present invention;

FIG. 5 is a schematic view showing a moving process of a work piece in the present invention;

figure 6 is a schematic view of a jaw assembly of the present invention.

Reference numerals of the above figures: 1. a nut; 11. presetting a blank; 12. a straight section; 13. a first inner bore; 14. a second inner bore; 15. a presetting section; 16. a flange; 17. a nut body; 18. a central bore; l, a preset distance;

2. a jaw assembly; 21. a clamping jaw; 211. a first clamping part; 212. a second clamping part; 213. a first clamping space; 214. a second gripping space;

3. a first mold; 4. a second mold; 5. a third mold; 6. a fourth mold; 7. a fifth mold;

8. performing primary molding; 81. a main formwork; 82. a main die cushion block; 83. a main die thimble; 84. a main mold core; 85. pushing out the thimble; 86. a pipe pushing cushion block; 87. pushing the tube; 88. a channel;

9. punching a die; 91. punching a mould shell; 92. punching a cushion block; 93. punching a thimble;

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The first embodiment is as follows: referring to fig. 1 to 6, a cold heading device for a nut, wherein the nut 1 comprises a nut body 17 and a flange 16 sleeved on the nut body 17, a preset distance L is formed between an end of one end of the nut body 17 and an end of one end of the flange 16 adjacent to the nut body 17, and the preset distance L is not more than 5 mm; the cold heading device includes:

a first die 3, said first die 3 being adapted to shape a first portion of a predetermined blank 11 into a straight section 12;

a second die 4, wherein the second die 4 is used for extruding and forming a first inner hole 13 in the straight section part 12;

a third die 5, said third die 5 being adapted to extrude a second inner bore 14 within a second portion of said predetermined blank 11;

a fourth die 6, said fourth die 6 being adapted to form a flange 16 between said straight section 12 and said second portion, and to form a predetermined portion 15 having said predetermined distance L between an end of said second portion and an end of said flange 16 adjacent to said second portion;

a fifth die 7, wherein the fifth die 7 is used for separating the scraps positioned between the first inner hole 13 and the second inner hole 14 from the machined part, so that the first inner hole 13 is communicated with the second inner hole 14 to form a central hole 18;

a clamping jaw assembly 2 for moving the workpiece is arranged between the fourth die 6 and the fifth die 7, the clamping jaw assembly 2 at least comprises two clamping jaws 21 which are arranged oppositely, each clamping jaw 21 comprises a first clamping portion 211 attached to the side surface of the flange 16 and a second clamping portion 212 attached to the side surface of the preset portion 15, a first clamping space 213 matched with the flange 16 is formed between the first clamping portions 211 which are opposite, and a second clamping space 214 matched with the preset portion 15 is formed between the second clamping portions 212 which are opposite.

The original clamping jaw in the original cold heading device clamps the preset part 15 from one end of the nut 1, but the nut 1 comprises the flange 16, the diameter of the flange 16 is about 19.5mm, and the preset distance L of the preset part 15 is not more than 5mm, so that the original clamping jaw can be abutted against the flange 16 in the clamping process, and the effective clamping force cannot be applied to the preset part 15. Therefore, the central hole 18 in the nut 1 cannot be formed by the cold heading device in the original process. Machining is required to complete the operations of outer diameter/face turning, drilling, tapping, etc. The clamping jaw 21 comprises a first clamping part 211 attached to the side surface of the flange 16 and a second clamping part 212 attached to the side surface of the presetting part 15, so that the attaching area of the clamping jaw 21 and the nut 1 is increased, and the movement of a workpiece between the dies is realized. The workpiece is conveniently moved to the fifth die, and the scrap between the first inner hole 13 and the second inner hole 14 is separated from the workpiece by the fifth die to form a central hole 18, wherein the diameter of the central hole 18 is about 5.5mm to 5.6 mm. By forming the central bore 18 by cold heading, the number of machining steps is reduced and the machining efficiency is improved.

Referring to fig. 2, each of the first mold 3, the second mold 4, the third mold 5, the fourth mold 6, and the fifth mold 7 includes a main mold 8 and a punch 9 that are disposed correspondingly;

the main mold 8 comprises a main mold 81, a main mold cushion block 82, a main mold thimble 83 and a main mold core 84, which are arranged in the main mold 81, wherein the main mold core 84 is provided with a main mold cavity with an opening facing the die 9, and the main mold thimble 83 penetrates through the main mold cushion block 82;

the die 9 comprises a die stamping shell 91, a die stamping cushion block 92 and a die stamping ejector pin 93 which are arranged in the die stamping shell 91, one end of the die stamping ejector pin 93 is connected with the die stamping cushion block 92, and the other end of the die stamping ejector pin 93 penetrates through the die stamping shell 91 to be opposite to the main die cavity.

The main mold 8 of the second mold 4, the third mold 5, and the fourth mold 6 further includes a push-out thimble 85, the push-out thimble 85 is disposed to penetrate through the main mold cushion block 82, a top end of the push-out thimble 85 abuts against a bottom of a push tube cushion block 86 sleeved on the main mold thimble 83, a push tube 87 sleeved on the main mold thimble 83 abuts against a top of the push tube cushion block 86, and a top end of the push tube 87 abuts against a section of the straight section 12. In the cold heading process, a section of the main die ejector pin 83 is arranged in the first inner hole 13, and the top end of the ejector tube 87 abuts against the end of the straight section 12. After the cold heading is completed, the die ejector pin 83 moves upward, so that an upward force is applied to the push tube cushion block 86, and the push tube cushion block 86 drives the push tube 87 to move upward, so that the workpiece is pushed out from the cavity of the main die.

Referring to fig. 2, a spring is arranged in the main die 8 of the second die 4, and after the punch ejector pin 93 pushes the workpiece into the main die cavity to form a closed die cavity, the spring contracts, and the workpiece flows to form the first inner hole 13.

Referring to fig. 1, the main mold 8 of the fifth mold 7 has a passage 88 communicating with the inside of the push tube 87, and the scrap can slide down along the passage 88 under the punching of the punch pin 93.

Referring to fig. 4, when the workpiece in the fourth mold 6 is in the demolding state, the first clamping space 213 is opposite to the main cavity of the fourth mold 6, the predetermined portion 15 is located in the first clamping space 213, and a part of the flange 16 is attached to the first clamping portion 211. Through the action of the push pipe 87 and the die ejector pin 93, the workpiece enters the first clamping space 213 along the first clamping part 211 until the preset part 15 enters the second clamping space 214, and the flange 16 abuts against the inner wall between the first clamping space 213 and the second clamping space 214.

In a preferred embodiment, the first clamp 211 and the second clamp 212 are both arc-shaped surfaces, and in the clamping state, the arc-shaped surfaces are in surface contact with the side surface of the workpiece. The design of the arc-shaped surface enables the clamping jaw 21 to surround the outer side of the nut 1, so that the clamping jaw plays a role in fixing and is prevented from falling from the adjacent clamping jaws 21.

During the process of the nut 1, the main die 8 and the punch die 9 are horizontally arranged. The clamping jaws 21 arranged between adjacent dies extend in the horizontal direction. In the clamping process, the clamping part surrounds the nut 1 from the peripheral side, and the clamping part of the clamping jaw 21 is an arc-shaped surface, so that the bottom of the nut 1 is supported, and the two sides of the nut 1 are limited. Preferably, the clamping jaws 21 comprise two parts, which are oppositely arranged on two sides of the nut 1 along the horizontal direction.

Referring to fig. 2, a relief portion is formed between the first clip portion 211 and the second clip portion 212, and the width of the relief portion is smaller than that of the flange 16. The avoiding part can be used for avoiding partial burrs on the nut 1.

A nut is shown in figure 1 and comprises a nut body 17 and a flange 16 sleeved on the nut body 17, a central hole 18 is formed in the nut body 17, a preset distance L is formed between the end portion of one end of the nut body 17 and the end portion of one end, close to the nut body 17, of the flange 16, the preset distance L is not larger than 5mm, and the nut 1 is formed by cold heading.

A clamping jaw assembly is used for moving a workpiece in the cold forging device and comprises at least two clamping jaws 21 which are oppositely arranged, wherein each clamping jaw 21 comprises a clamping part, a clamping space matched with the workpiece is formed between the opposite clamping parts, and the clamping parts are attached to the side forming surfaces of the workpiece when the workpiece is moved.

The principle and the implementation mode of the invention are explained by applying specific embodiments in the invention, and the description of the embodiments is only used for helping to understand the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.

Claims

1. A cold heading device for a nut is disclosed, wherein the nut comprises a nut body and a flange sleeved on the nut body, a preset distance is formed between the end part of one end of the nut body and the end part of one end, close to the nut body, of the flange, and the preset distance is not more than 5 mm; its characterized in that, cold-heading device includes:

a second die for extruding a first bore within the straight section;

2. A cold heading device for a nut as claimed in claim 1, wherein: when the workpiece in the fourth mold is in a demolding state, the first clamping space is opposite to the main mold cavity of the fourth mold, the preset part is located in the first clamping space, and part of the flange is attached to the first clamping part.

3. A cold heading device for a nut as claimed in claim 1, wherein: the first clamping part and the second clamping part are both arc-shaped surfaces, and when the clamping part is in a clamping state, the arc-shaped surfaces are in surface contact with the side surfaces of the machined part.

4. A cold heading device for a nut as claimed in claim 1, wherein: the clamping jaw extends along the horizontal direction.

5. A cold heading device for a nut as claimed in claim 1, wherein: the first clamping part and the second clamping part are inwards recessed to form an avoiding part, and the width of the avoiding part is smaller than that of the flange.

6. A cold heading device for a nut as claimed in claim 1, wherein: the first mould, the second mould, the third mould, the fourth mould and the fifth mould respectively comprise a main mould and a stamping mould which are correspondingly arranged;

7. A cold-heading device for nuts, as claimed in claim 6, wherein: the main die of the second die, the third die and the fourth die further comprises a push-out thimble, the push-out thimble penetrates through the main die cushion block, the top end of the push-out thimble abuts against the bottom of a push tube cushion block sleeved on the main die thimble, a push tube sleeved on the main die thimble abuts against the top of the push tube cushion block, and the top end of the push tube abuts against the end part of the straight section part.

8. A cold-heading device for nuts, as claimed in claim 7, wherein: and a channel communicated with the inside of the push pipe is arranged in the main die of the fifth die, and the waste material can slide down along the channel under the stamping of the stamping die thimble.

9. A nut, characterized in that: establish including nut body and cover flange on the nut body, including the centre bore in the nut body, the tip of the one end of nut body with the flange close on in form between the tip of the one end of nut body and predetermine the distance, it is not more than 5mm to predetermine the distance, should the nut is whole to be formed by the cold-heading.

10. A jaw assembly for use in moving a workpiece in a cold forging apparatus as set forth in claim 1, wherein: the clamping jaw comprises two opposite clamping jaws, a clamping space matched with the workpiece is formed between the opposite clamping jaws, and when the workpiece is moved, the clamping jaws are attached to the side forming surfaces of the workpiece.