CN107520389B

CN107520389B - Chamfering die and chamfering method

Info

Publication number: CN107520389B
Application number: CN201710763802.1A
Authority: CN
Inventors: 任鹏波; 毛春平; 邓建
Original assignee: ZHEJIANG NEW ORIENTAL FASTENER CO Ltd
Current assignee: ZHEJIANG NEW ORIENTAL FASTENER CO Ltd
Priority date: 2017-08-30
Filing date: 2017-08-30
Publication date: 2023-08-22
Anticipated expiration: 2037-08-30
Also published as: CN107520389A

Abstract

The application relates to the technical field of machining, and particularly discloses a chamfering die and a chamfering method, wherein a chamfering forming hole consists of a first conical chamfer hole and a second conical chamfer hole, and the taper angle of the first conical chamfer hole is smaller than that of the second conical chamfer hole.

Description

Chamfering die and chamfering method

Technical Field

The application relates to the technical field of machining, in particular to a chamfering die and a chamfering method.

Background

The chamfering process of the bar stock is usually performed by turning, but the chamfering mode by turning is usually applied to the machining of the turning piece. The chamfering processing can be carried out on cast parts and forged parts in a turning mode, but the defects of long clamping occupied time and low efficiency exist. Therefore, a chamfering die for forging and forming a chamfer is developed for such parts. This kind of chamfer mold for processing refer to fig. 1, including mould body 1, be equipped with mould pressing hole 11 and liftout hole 12 in this mould body, be equipped with toper chamfer hole 13 between the lower extreme of mould pressing hole 11 and the liftout hole 12, the major diameter of toper chamfer hole is the same with mould pressing hole 11 diameter, and the minor diameter of toper chamfer hole 13 is the same with liftout hole 12 diameter.

The ejector rod 2 is positioned in the ejector hole 12 in the forging and pressing chamfering process, the upper end face of the ejector rod is flush with the upper end face of the ejector hole, and a certain gap is reserved between the ejector rod and the ejector hole. The die assembly 4 applies downward pressure to the bar 5 forcing the lower end of the bar 5 through the tapered chamfer hole 13 to squeeze the chamfer 54 shown in fig. 4. The chamfering die with the structure has the defect that the speed and the travel of the bar 5 in the descending process under the action of pressure are not easy to control, the bar is extremely easy to be overpressured, and the lower edge enters the gap between the ejector rod and the ejector hole, so that the annular blank holder 55 shown in fig. 4 is formed. After the annular pressing edge 55 appears, the ejector rod is easy to be blocked; meanwhile, grinding or turning trimming processing is carried out on the product with the annular blank pressing, so that the working procedures are increased undoubtedly, the production cost is improved, and the production efficiency is reduced.

Disclosure of Invention

The application aims to solve the technical problem that the existing forging and forming chamfering die is easy to cause annular blank pressing of products.

In order to solve the technical problems, the technical scheme provided by the application is as follows: the chamfering die at least comprises a die body, wherein a die pressing hole and a jacking hole which are coaxial and communicated with each other are arranged in the die body, a chamfering forming hole is arranged between the die pressing hole and the jacking hole, the chamfering forming hole comprises a conical chamfer hole I and a conical chamfer hole II, an upper orifice of the conical chamfer hole I is connected with a lower orifice of the die pressing hole, and a lower orifice of the conical chamfer hole II is connected with an upper orifice of the jacking hole; the taper angle of the first conical chamfer hole is smaller than that of the second conical chamfer hole.

In a preferred embodiment, the taper angle of the first tapered chamfer hole is α, and the taper angle of the second tapered chamfer hole is β, where α=40° to 50 °, and β=100° to 120 °.

In a preferred embodiment, the height of the chamfer forming hole is H, the height of the first tapered chamfer hole is H1, and the height of the second tapered chamfer hole is H2, wherein H1: h2: h= (0.15 to 0.25): (0.75 to 0.85): 1.

a preferred embodiment further comprises a ejector rod and an ejector driving mechanism for driving the ejector rod to axially move in the ejector hole, wherein the ejector rod is in clearance fit with the ejector hole.

A preferred embodiment further comprises a die assembly located above the die body.

A preferred embodiment further comprises a mold core arranged in the mold body, wherein the hardness of the mold core is greater than that of the mold body, and at least the mold pressing hole and the chamfer forming hole are positioned on the mold core.

In a preferred embodiment, at least a portion of the ejector aperture is provided in the mold core.

The chamfering method of the chamfering die comprises the following steps:

step 1, driving a material ejection rod to ascend by a material ejection driving mechanism until the upper surface of the material ejection rod is flush with an upper orifice of a material ejection hole;

step 2, placing the bar to be processed into the mould pressing hole;

step 3, driving the bar to descend to the lower end of the bar to enter a chamfer forming hole by a die assembly, wherein the resistance of the lower end of the bar in a second conical chamfer hole is larger than that in a first conical chamfer hole, and the descending speed in the second conical chamfer hole is smaller than that in the first conical chamfer hole;

and 4, retracting the die assembly, driving the ejector rod to move upwards by the ejector driving mechanism, ejecting the bar by the ejector rod, and finishing the chamfering processing procedure of the end part of the bar.

The chamfering die and the chamfering method have the advantages that in the process that a bar product to be processed enters the conical chamfer hole II from the conical chamfer hole I, the descending resistance of the bar product is increased due to the change (enlargement) of the conical chamfer hole II, the speed is reduced, the descending limit position of the bar is better controlled, the bar is effectively prevented from entering the gap between the ejector rod and the ejector hole due to exceeding the descending limit position, and annular blank pressing is avoided, so that the chamfering process is formed at one step, the production cost is reduced, and the production efficiency is improved.

Drawings

FIG. 1 is a schematic view of the chamfering die according to the present embodiment;

FIG. 2 is a schematic view of a partial enlarged structure of the chamfer forming hole in FIG. 1;

FIG. 3 is a schematic diagram of the product structure after the chamfering mold of the embodiment is processed;

fig. 4 is a schematic view of a partial structure of a product processed by a chamfering die in the prior art.

Detailed Description

The present application will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present application more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.

As shown in fig. 1, a chamfering die of the present embodiment includes a die body 1, a ejector pin 2, an ejector driving mechanism 3, and a die assembly 4. The die body 1 is internally provided with a die pressing hole 11 and a material ejection hole 12 which are coaxial and are mutually communicated, the die pressing hole 11 is used for accommodating a bar 5 to be processed with a chamfer, the material ejection hole 12 is internally used for accommodating a material ejection rod 2, and the material ejection rod 2 plays roles of supporting the lower end of the bar, limiting the descending limit position of the bar and ejecting the bar after the chamfer processing is finished.

In this embodiment, the ejector rod 2 is in clearance fit with the ejector hole 12, and the ejector rod 2 is driven to move in the ejector rod 2 by the ejector driving mechanism 3. It should be noted that, the ejector driving mechanism 3 and the die assembly 4 are not the points of the present application in the prior art, and the detailed description of the specific structure thereof is omitted.

As the greatest improvement of this embodiment, as shown in fig. 2, a chamfer forming hole 13 is provided between the molding hole 11 and the ejector hole 12, and the chamfer forming hole includes a tapered chamfer hole one 131 and a tapered chamfer hole two 132, wherein the upper orifice of the tapered chamfer hole one 131 is connected with the lower orifice of the molding hole 11, and the lower orifice of the tapered chamfer hole two 132 is connected with the upper orifice of the ejector hole 12.

Further, the taper angle of the first tapered chamfer hole 131 is smaller than the taper angle of the second tapered chamfer hole 132. Setting the taper angle of the first tapered chamfer hole 131 to be alpha and the taper angle of the second tapered chamfer hole 132 to be beta, alpha=40-50 DEG, and beta=100-120 deg.

Further, the height of the chamfer forming hole 13 is set to H, the height of the tapered chamfer hole one 131 is set to H1, and the height of the tapered chamfer hole two 132 is set to H2. Then in order to make the machined chamfer height meet the process requirements, h1 needs to be set: h2: h= (0.15 to 0.25): (0.75 to 0.85): 1.

in an alternative embodiment, in this embodiment, α=45° 5, β=110, the diameter a of the molding hole 11 is 20.9mm, the diameter c of the ejector hole 12 is 16mm, the lower orifice diameter of the tapered chamfer hole one 131, i.e., the upper orifice diameter b of the tapered chamfer hole two 132, is 18.2mm, and correspondingly, h=4.03 mm, h1=3.26 mm, and h2=0.77.

The structure of the finished bar product processed by this embodiment is shown in fig. 3, and the end of the bar body 51 forms a first chamfer surface 52 and a second chamfer surface 52, wherein the taper angle of the first chamfer surface 52 is smaller than the taper angle of the second chamfer surface 52.

A preferred embodiment is one in which the inside of the mould body 1 is provided with a mould core 14, the hardness of the mould core 14 being greater than the hardness of the mould body 1. At least the molding hole 11 and the chamfer forming hole 13 are located on the mold core, and at least a part of the ejector hole 12 is provided on the mold core 14. The purpose of this setting is that the material cost of reduction mould sets up the mold core 14 into removable structure simultaneously, then on the basis of mould body, through the mold core of changing different specifications, realizes the chamfer processing of the bar product of more specifications.

The chamfering method for machining chamfer by using the chamfering die of the embodiment comprises the following steps:

step 2, placing the bar to be processed into the mould pressing hole;

In summary, the foregoing description is only of the preferred embodiments of the application, and is not intended to limit the application to the particular embodiments disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the application.

Claims

1. The chamfering die at least comprises a die body, wherein a die pressing hole and a material ejection hole which are coaxial and communicated with each other are arranged in the die body, and a chamfering forming hole is arranged between the die pressing hole and the material ejection hole; the taper angle of the first conical chamfer hole is smaller than that of the second conical chamfer hole; the die comprises a die body, and is characterized by further comprising a die core arranged in the die body, wherein the die core is of a replaceable structure, the hardness of the die core is greater than that of the die body, and at least the die pressing hole and the chamfer forming hole are positioned on the die core.

2. The chamfer mold of claim 1, wherein the taper angle of the first tapered chamfer hole is α and the taper angle of the second tapered chamfer hole is β, where α = 40 ° to 50 °, β = 100 ° to 120 °.

3. The chamfer mold of claim 2, wherein the chamfer forming hole has a height H, the first tapered chamfer hole has a height H1, and the second tapered chamfer hole has a height H2, wherein H1: h2: h= (0.15 to 0.25): (0.75 to 0.85): 1.

4. a chamfer mould according to any one of claims 1-3, further comprising a ejector rod and an ejector drive mechanism for driving the ejector rod axially within the ejector bore, the ejector rod being in clearance fit with the ejector bore.

5. The chamfer mold of claim 4, further comprising a die assembly located above the mold body.

6. The chamfer mold according to any one of claims 1-3 or 5, wherein at least a portion of the ejector bore is provided on the mold core.

7. A chamfering method of the chamfering die as set forth in claim 5, characterized by comprising the steps of:

step 2, placing the bar to be processed into the mould pressing hole;