CN214920167U

CN214920167U - Reducing female die and cold heading die

Info

Publication number: CN214920167U
Application number: CN202120802578.4U
Authority: CN
Inventors: 赵辉
Original assignee: Fasteners Branch Co Of Fawer Automotive Parts Co ltd; Fawer Automotive Parts Co Ltd
Current assignee: Fasteners Branch Co Of Fawer Automotive Parts Co ltd; Fawer Automotive Parts Co Ltd
Priority date: 2021-04-19
Filing date: 2021-04-19
Publication date: 2021-11-30
Anticipated expiration: 2031-04-19

Abstract

The utility model relates to a cold-heading forming die technical field especially relates to a thin die and cold-heading mould contract. The shrinkage female die comprises a female die body, a shrinkage hole, a transition hole and a preformed hole; the female die body is provided with a working end face, the opening of the preformed hole is formed in the working end face, the shrinkage hole is formed in the female die body, and two ends of the transition hole are respectively communicated with the shrinkage hole and the bottom of the preformed hole; the preformed hole and the transition hole are tapered holes with larger size towards one end of the working end face, the preformed hole and the transition hole are connected through an arc connecting section, and the arc connecting section is tangent to the hole wall of the preformed hole and the hole wall of the transition hole respectively. The cold heading die comprises the reducing female die. This shrink die and cold-heading mould, arc linkage segment are tangent with the pore wall of preformed hole and the pore wall of transition hole respectively, form smooth transition between first convergent section and second convergent section, avoid forming the cave-in between the two, avoid forming irregular fold or stress concentration in follow-up manufacturing procedure.

Description

Reducing female die and cold heading die

Technical Field

The utility model relates to a cold-heading forming die technical field especially relates to a thin die and cold-heading mould contract.

Background

In the process of processing the stepped rod piece by adopting the cold heading forming method, a convex die and a reducing concave die are matched to process the equal-diameter rod piece. In the related art, as shown in fig. 1, a state is shown in which a punch 1 ' is cold-headed together with a reducing die 2 ' to form a stepped bar 3 ', and specifically, the punch 1 ' is used to press an equal-diameter straight bar into the reducing die 2 ', and a portion of the equal-diameter straight bar pressed into the reducing die 2 ' is reduced, so that the equal-diameter straight bar is formed into the stepped bar 3 '.

As shown in fig. 2 to 4, which are a schematic structural diagram of the reducing die 2 ', a partially enlarged view of the reducing die 2 ' at a, and a schematic structural diagram of the stepped rod 3 ' obtained by cold heading and reducing, respectively, it can be known that, due to unreasonable structures such as the pre-forming angle 21 ' and the sharp bevel 20 ' formed at the opening of the forming hole of the reducing die 2 ', the formed stepped rod 3 ' is likely to form the non-smooth transition dead zone 30 ' shown in fig. 4 at the shoulder, and the dead zone 30 ' is likely to have wrinkles or end-turns in the next process, thereby causing the product quality to be unqualified.

SUMMERY OF THE UTILITY MODEL

A first object of the utility model is to provide a reduce thin die to solve current thin die structure and unreasonable the technical problem who leads to the work piece after the shaping to form the blind spot of unsmooth transition easily to a certain extent.

A second object of the utility model is to provide a cold-heading mould to solve the work piece that the thin die that contracts of current cold-heading grinding apparatus leads to after the shaping easily at the shoulder department and form the technical problem in the blind spot of unsmooth transition to a certain extent.

In order to achieve the above object, the present invention provides the following technical solutions;

based on the first purpose, the utility model provides a reducing concave die, which comprises a concave die body, a reducing hole, a transition hole and a preformed hole;

the female die body is provided with a working end face, an opening of the preformed hole is formed in the working end face, the shrinkage hole is formed in the female die body, and two ends of the transition hole are respectively communicated with the shrinkage hole and the bottom of the preformed hole;

the preformed hole with the transition hole is the orientation the great bell mouth of one end size of working end face, just the preformed hole with the transition hole passes through the arc linkage segment and connects, the arc linkage segment respectively with the pore wall in preformed hole with the pore wall in transition hole is tangent.

In any of the above solutions, optionally, the fine shrinkage hole, the transition hole, the arc connecting section, and the preformed hole are all a revolving body with a predetermined axis as a central rotation axis.

In any of the above solutions, optionally, the curvature of the arc-shaped connecting section in the axial section is equal everywhere.

In any of the above solutions, optionally, the direction from the transition hole to the preformed hole along the predetermined axis is defined as a positive direction of the predetermined axis;

the hole wall of the transition hole forms a first included angle with the positive direction of the preset axis under the axial cross section, and the first included angle is 10-20 degrees.

In any of the above technical solutions, optionally, the first included angle is 15 °.

In any of the above technical solutions, optionally, a second included angle is formed between the hole wall of the preformed hole and the positive direction of the common axis under the radial interface, and the second included angle is 25 to 45 °.

In any of the above technical solutions, optionally, the second included angle is 25 to 35 °.

In any of the above technical solutions, optionally, the second included angle is 30 °.

In any of the above technical solutions, optionally, a depth of the preformed hole is not less than a depth of the transition hole.

Based on above-mentioned second purpose, the utility model provides a cold-heading mould, the thin die that contracts that provides including above-mentioned arbitrary technical scheme.

Adopt above-mentioned technical scheme, the beneficial effects of the utility model are that:

the utility model provides a thin die contracts, include the die body, contract pore, transition hole and preforming hole. Wherein, preformed hole, transition hole and the pore that contracts set up in the inside of die body in order to at the first convergent section of the stage shaping in order of the undergauge, second convergent section and the section of reducing the footpath. The preformed hole and the transition hole are tapered holes with larger size towards one end of the working end surface, so that the first tapered section and the human tapered section form a tapered shape with gradually reduced radial size towards the reduced diameter section; and the preforming hole is connected with the transition hole through the arc connecting section, and the arc connecting section is tangent to the hole wall of the preforming hole and the hole wall of the transition hole respectively, so that smooth transition is formed between the first reducing section and the second reducing section, depression is prevented from being formed between the first reducing section and the second reducing section, further irregular folds or stress concentration in subsequent processing procedures is avoided, the risk of turning around of a bolt is reduced, namely the obtained step rod piece can be smoothly unfolded in the subsequent processing procedures, and the product quality is ensured.

The utility model provides a cold-heading mould, including foretell thin die that contracts, therefore can realize this all beneficial effects of the thin die that contracts.

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

FIG. 1 is a schematic view of the working state of a cold heading die in the prior art;

FIG. 2 is a schematic structural view of a prior art reduction die;

FIG. 3 is an enlarged view of a portion of FIG. 2 at A;

FIG. 4 is a schematic structural view of a stepped rod member formed by a cold heading die according to the prior art;

fig. 5 is a schematic structural view of a narrowing die provided in an embodiment of the present invention;

fig. 6 is a schematic view of an operating state of a cold heading die provided by the second embodiment of the present invention;

fig. 7 is a schematic structural view of a step rod formed by the cold heading die according to the second embodiment of the present invention.

Icons in fig. 1 to 4: 1' -a male die; 2' -reducing the female die; 20' -sharp break angle; 21' -a pre-form angle; 3' -a step bar; 30' -dead zone.

Icons in fig. 5 to 7: 1-male die; 2-a female die; 20-a female die body; 21-preforming holes; 210-a first base contour; 22-a transition hole; 220-a second base contour; 23-reducing the diameter of the hole; 230-a third base contour; 24-an arcuate connecting section; 240-fourth base outline; 25-a first included angle; 26-a second included angle; 27-a working end face; 3-a rod-shaped workpiece; 30-a first part; 31-a second part; 310-a first tapered section; 311-a second tapered section; 312-reducing section.

Detailed Description

The technical solution of the present invention will be described clearly and completely with reference to the accompanying drawings, and obviously, the described embodiments are some, but not all embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Example one

Referring to fig. 5 in conjunction with fig. 6 and 7, the present embodiment provides a reduction die; fig. 5 is a schematic structural view of the reduction die provided in this embodiment.

The reduction die that this embodiment provided is used for cold-heading mould.

Referring to fig. 5 in conjunction with fig. 6 and 7, the present embodiment provides a reduction die 2, which includes a die body 20, a reduction hole, a transition hole 22 and a pre-forming hole 21.

Hereinafter, the above-described components of the reduction die 2 will be described in detail.

The rod-shaped workpiece 3 can be divided into a first portion 30 and a second portion 31 connected in the length direction thereof, wherein, in the reducing stage, the second portion 31 is a portion to be reduced by cold heading, and the first portion 30 is a portion for being fixed in the punch 1.

In the present embodiment, the die body 20 has a working end face 27, and the opening of the preforming hole 21 is opened in the working end face 27 so that the punch 1 can press the second portion 31 of the rod-like workpiece 3 into the preforming hole 21 from the side of the working end face 27.

The shrinkage hole is arranged in the female die body 20, and two ends of the transition hole 22 are respectively communicated with the shrinkage hole and the bottom of the preformed hole 21, so that the male die 1 can press the second part 31 of the rod-shaped workpiece 3 into the shrinkage hole from the preformed hole 21 through the transition hole 22, and the second part 31 is subjected to cold heading forming in the shrinkage hole.

Optionally, the die body 20 is cylindrical, the working end face 27 is formed at one end of the die body 20 along the axial direction of the die body, and the working end face 27 may be a plane or a curved surface.

The pre-forming hole 21 and the transition hole 22 are tapered holes with a larger size towards one end of the working end face 27, so that the second portion 31 can form a first tapered section 310 formed in the pre-forming hole 21, a second tapered section 311 formed in the transition hole 22 and a tapered section formed in the tapered hole, and further through the first tapered section 310 and the second tapered section 311, the radial size of the joint of the first portion 30 and the tapered section can be ensured to be gradually reduced instead of suddenly reduced, so that the stress of the joint can be more uniform and reasonable in the subsequent heading process, and the situation that the first portion 30 falls off from the second portion 31 in the heading process is avoided, that is, the occurrence probability of the turning-around situation of the rod-shaped workpiece 3 can be remarkably reduced.

The preformed hole 21 is connected with the transition hole 22 through the arc connecting section 24, and the arc connecting section 24 is tangent with the pore wall of the preformed hole 21 and the pore wall of the transition hole 22 respectively, so that the preformed hole 21 and the transition hole 22 form smooth transition at the joint between the preformed hole and the transition hole, and further the joint of the first reducing section 310 and the second reducing section 311 can form smooth transition, thereby avoiding forming circumferential depression and improving the smoothness of the metal material spreading at the joint. Therefore, the probability of forming wrinkles in the subsequent pier head process can be remarkably reduced, so that stress concentration is reduced, and the mechanical property of the bolt cannot be negatively influenced by cold heading reducing operation.

In an alternative of this embodiment, the shrinkage cavity, the transition hole 22, the arc-shaped connecting section 24 and the preformed hole 21 are all a body of revolution having a predetermined axis as a center of rotation. Wherein, any plane where the predetermined axis is located is defined as an axial section, the female die body 20 is cut along the axial section, and the contour lines of the preformed hole 21, the arc-shaped connecting section 24, the transition hole 22 and the shrinkage hole which are respectively intersected with the axial section are a first basic contour line 210, a second basic contour line 220, a third basic contour line 230 and a fourth basic contour line 240.

The first basic contour line 210 rotates for a circle around the central rotating shaft to obtain the preformed hole 21, the second basic contour line 220 rotates for a circle around the central rotating shaft to obtain the arc-shaped connecting section 24, the third basic contour line 230 rotates for a circle around the central rotating shaft to obtain the transition hole 22, and the fourth basic contour line 240 rotates for a circle around the central rotating shaft to obtain the shrinkage hole.

First base contour line 210 is a straight line that forms a second included angle 26 with the central axis of rotation, second base contour line 220 is an arc that is tangent to first base contour line 210 and third base contour line 230, third base contour line 230 is a straight line that forms a first included angle 25 with the central axis of rotation, and fourth base contour line 240 is a straight line that is parallel to the central axis of rotation.

In this embodiment, the shrinkage hole, the transition hole 22, the arc-shaped connecting section 24 and the pre-forming hole 21 are all set as a revolving body, so that the female die body 20 is convenient to machine and form, and the requirements on the cold heading shrinkage quality of the bolt product performance and the subsequent machining process can be met.

In an alternative embodiment, the curvature of the curved connecting section 24 in the axial section is equal everywhere, i.e. the second base contour line 220 is a circular arc, the center of which is located on the side of the circular arc facing away from the predetermined axis.

In an alternative of this embodiment, the direction pointing from the transition hole 22 to the preformed hole 21 along the predetermined axis is defined as the positive direction of the predetermined axis.

The hole wall of the transition hole 22 forms a first included angle 25 with the positive direction of the predetermined axis in the axial cross section, the first included angle 25 is 10 to 20 °, that is, the first basic contour line 210 forms the first included angle 25 of 10 to 20 ° with the positive direction of the predetermined axis, so that the second tapered section 311 inclines 10 to 20 ° radially outwards relative to the reduced diameter section 312, so that the second tapered section 311 can play a reasonable transition role between the reduced diameter section 312 and the first tapered section 310. Optionally, the first included angle 25 is 10 °, 12 °, 15 °, 18 °, or 20 °. In an alternative embodiment, the wall of the preformed hole 21 forms a second angle 26 with the positive direction of the common axis at the radial interface, the second angle 26 being 25-45 °, i.e. the first base contour 210 forms a second angle 26 of 25-45 ° with the positive direction of the predetermined axis, so that the first tapered section 310 is inclined 25-45 outwards with respect to the first portion 30, so that the first tapered section 310 can provide a reasonable transition between the second tapered section 311 and the first portion 30.

Optionally, the second included angle 26 is 25-35 °, so that the first tapered section 310 is inclined to a lesser degree radially outward relative to the second tapered section 311, thereby ensuring that the arcuate connecting section 24 is more capable of forming a smoother transition connection between the first tapered section 310 and the second tapered section 311.

Optionally, the second included angle 26 is 25 °, 28 °, 30 °, 32 °, or 35 °.

In the alternative of this embodiment, the first included angle 25 is 15 °, the second included angle 26 is 30 °, and the difference between the first included angle 25 and the second included angle 26 is small, so as to provide a structural basis for machining the arc-shaped connecting section 24, and compared with the technical scheme in the prior art in which the second included angle 26 is set to 60 °, a transition connection is made possible, and thus a technical problem that stress concentration is easily generated at the connection between the first portion 30 and the second portion 31 is eliminated is made possible.

In an alternative of this embodiment, since the first tapered section 310 formed in the preformed hole 21 is closer to the first portion 30 than the second tapered section 311 formed in the transition hole 22, and the first portion 30 needs to be upset in the subsequent heading process, the upsetting effect applied to the first tapered section 310 is greater than the upsetting effect applied to the second tapered section 311, so that the depth of the preformed hole 21 is not less than the depth of the transition hole 22, and the length of the first tapered section 310 can be ensured to be greater than the length of the second tapered section 311, so as to meet the subsequent upsetting requirement.

Example two

The second embodiment provides a cold heading die, the second embodiment comprises the reducing female die of the first embodiment, the technical characteristics of the reducing female die disclosed in the first embodiment are also applicable to the second embodiment, and the technical characteristics of the reducing female die disclosed in the first embodiment are not repeatedly described.

Fig. 6 is a schematic view of the working state of the cold heading die provided by the embodiment; fig. 7 is a schematic structural view of a stepped rod formed by the cold heading die of the cold heading die according to the embodiment.

Referring to fig. 6 and 7 in combination with fig. 5, the cold heading die provided by the present embodiment includes a reduction die 2. Optionally, the cold heading die further comprises a punch 1 used in cooperation with the reduction die 2, and the working end surface 27 of the reduction die 2 is used for facing the punch 1.

The cold heading die in the embodiment has the advantages of the reduction female die in the first embodiment, and the advantages of the reduction female die disclosed in the first embodiment are not described repeatedly.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention. Furthermore, those skilled in the art will appreciate that while some embodiments described herein include some features included in other embodiments, rather than other features, combinations of features of different embodiments are meant to be within the scope of the invention and form different embodiments. For example, any of the claimed embodiments may be used in any combination. The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information constitutes prior art already known to a person skilled in the art.

Claims

1. A shrinkage female die is characterized by comprising a female die body, a shrinkage hole, a transition hole and a pre-forming hole;

2. The reduction die according to claim 1, wherein the fine reduction hole, the transition hole, the arc-shaped connecting section and the preforming hole are all revolution bodies having a rotation axis centering on a predetermined axis.

3. The reduction die according to claim 2, characterized in that the curvature of the arc-shaped connecting section in axial section is equal everywhere.

4. The reduction die according to claim 2, characterized in that the direction directed along the predetermined axis from the transition hole to the preformed hole is defined as the positive direction of the predetermined axis;

5. The reduction die of claim 4, wherein said first included angle is 15 °.

6. A reducing die according to claim 4 wherein the walls of the preformed holes at the radial interface are at a second angle to the positive direction of the common axis, said second angle being in the range 25 ° to 45 °.

7. The reduction die of claim 6, wherein said second included angle is 25-35 °.

8. The reduction die of claim 7, wherein said second included angle is 30 °.

9. The reduction die of claim 1, wherein the depth of the preformed hole is not less than the depth of the transition hole.

10. A cold heading die comprising the reduction die of any one of claims 1 to 9.