阅读说明：本技术 双头丝锥 (Double-head screw tap ) 是由 董向阳 于 2018-06-30 设计创作，主要内容包括：本发明涉及双头丝锥。包括固定柱,所述固定柱两端分别设有丝锥柄,丝锥柄的前端设有攻丝部,所述攻丝部上设有攻丝螺纹,攻丝部的外圆周上均匀设有若干排屑槽,所述排屑槽内设有沿轴向方向延伸的刻度,所述攻丝部前端设有导向柱,导向柱的直径小于攻丝部的小径,导向柱的前端设有前锥,固定柱呈正直六棱柱状,固定柱的棱柱侧面上开设有三个定位孔,三个定位孔在正直六棱柱面上互成120度分布。本发明结构简单,通过固定柱两端均设置攻丝部,当一端发生损坏时,能够及时进行掉头更换,方便快捷,减少资源浪费,通过在固定柱的六棱柱侧面上开设三个定位孔,提高夹持稳定性,减少异动或晃动,从而保证加工精度。(The invention relates to a double-ended tap. The guide post is arranged at the front end of the tapping part, the diameter of the guide post is smaller than the small diameter of the tapping part, a front cone is arranged at the front end of the guide post, the fixing post is in a regular hexagonal prism shape, three positioning holes are formed in the side surface of the prism of the fixing post, and the three positioning holes are distributed on the regular hexagonal prism surface at 120 degrees. The hexagonal prism-shaped clamping fixture is simple in structure, the tapping parts are arranged at the two ends of the fixing column, when one end of the fixing column is damaged, the tapping parts can be turned around and replaced in time, convenience and rapidness are achieved, resource waste is reduced, the clamping stability is improved, abnormal movement or shaking is reduced by arranging the three positioning holes on the side face of the hexagonal prism of the fixing column, and therefore machining precision is guaranteed.)

1. The double-end screw tap is characterized by comprising a fixed column, wherein screw tap handles are respectively arranged at two ends of the fixed column, a tapping part is arranged at the front end of each screw tap handle, tapping threads are arranged on the tapping part, a plurality of chip grooves are uniformly formed in the outer circumference of the tapping part, scales extending along the axial direction are arranged in the chip grooves, a guide column is arranged at the front end of the tapping part, the diameter of the guide column is smaller than the small diameter of the tapping part, a front cone is arranged at the front end of the guide column, the fixed column is in a regular hexagonal prism shape, three positioning holes are formed in the side surface of the prism of the fixed column, and the three positioning holes are mutually distributed on the regular hexagonal prism surface at.

2. The double-ended tap according to claim 1, wherein a tapered transition section is provided at the junction of the guide post and the tap portion.

3. The double-ended tap according to claim 2, wherein the outer surfaces of the tapping portion, the guide post, the tapered transition section and the nose cone are provided with a hard wear-resistant coating of boron nitride.

4. The double-ended tap according to claim 3, wherein said hard wear resistant coating of boron nitride has a thickness of 23 mm.

5. The double-ended tap according to claim 1, wherein a depth of a distal end of the chip flute becomes gradually shallower from front to rear.

Technical Field

The invention relates to a screw tap, in particular to a double-end screw tap, and belongs to the technical field of hardware tools.

Background

A screw tap is a common hardware tool, and is generally used for machining cylindrical or conical internal threads, also called a screw tap, on a workpiece. The tap can be classified into a spiral tap and a straight-edge tap according to the shape, and can be classified into a hand tap and a machine tap according to the use environment. The existing screw tap is basically a single-head screw tap and comprises a screw tap body and a screw tap handle, tapping threads are arranged on the screw tap body, when the screw tap body is damaged in the working process, the screw tap body needs to be disassembled for repair, and if the screw tap body is not repaired, the screw tap body is directly scrapped, so that the resource waste is caused, and the production efficiency is influenced; the centre gripping stability at screw tap centre gripping position is the important factor that influences the machining precision, and optical axis handle or right angle handle are often processed into to traditional screw tap handle, and the optical axis handle screw tap appears skidding easily in the processing, follows the commentaries on classics phenomenon, and axial stability can all be relatively poor, and right angle handle screw tap circumference centre gripping is comparatively stable, can not appear skidding or follow the commentaries on classics phenomenon, but the axial of right angle handle screw tap still can appear the phenomenon of transaction and rocking, and the machining precision improves unobviously.

Disclosure of Invention

In view of the above defects, the invention aims to provide a double-end screw tap, the two ends of which can be tapped, the replacement of which is convenient and fast, the resource waste is reduced, the clamping stability is improved, the abnormal movement or shaking is reduced, and the processing precision is ensured.

Therefore, the technical scheme adopted by the invention is as follows:

the guide post is arranged at the front end of the tapping part, the diameter of the guide post is smaller than the small diameter of the tapping part, a front cone is arranged at the front end of the guide post, the fixing post is in a regular hexagonal prism shape, three positioning holes are formed in the side surface of the prism of the fixing post, and the three positioning holes are distributed on the regular hexagonal prism surface at 120 degrees.

As a further improvement of the technical scheme, a conical transition section is arranged at the joint of the guide column and the tapping part.

As a further improvement of the technical scheme, the outer surfaces of the tapping part, the guide post, the conical transition section and the front cone are provided with boron nitride hard wear-resistant coatings.

As a further improvement of the technical scheme, the thickness of the boron nitride hard wear-resistant coating is 23 mm.

As a further improvement of the technical scheme, the depth of the tail end of the chip groove becomes shallow gradually from front to back.

The invention has the advantages that:

the hexagonal prism-shaped clamping fixture is simple in structure, the tapping parts are arranged at the two ends of the fixing column, when one end of the fixing column is damaged, the tapping parts can be turned around and replaced in time, convenience and rapidness are achieved, resource waste is reduced, the clamping stability is improved, abnormal movement or shaking is reduced by arranging the three positioning holes on the side face of the hexagonal prism of the fixing column, and therefore machining precision is guaranteed.

Drawings

Fig. 1 is a schematic structural view of the present invention.

Fig. 2 is a cross-sectional view a-a of fig. 1.

In the figure, 1 is a fixing column, 2 is a screw tap handle, 3 is a tapping part, 4 is a chip groove, 5 is a scale, 6 is a guide column, 7 is a front cone, 8 is a positioning hole, and 9 is a conical transition section.

Detailed Description

The double-end screw tap comprises a fixed column 1, wherein two ends of the fixed column 1 are respectively provided with a screw tap handle 2, the front end of the screw tap handle 2 is provided with a tapping part 3, tapping threads are arranged on the tapping part 3, a plurality of chip grooves 4 are uniformly arranged on the outer circumference of the tapping part 3, scales 5 extending along the axial direction are arranged in the chip grooves 4, the front end of the tapping part 3 is provided with a guide post 6, the diameter of the guide post 6 is smaller than the small diameter of the tapping part 3, the front end of the guide post 6 is provided with a front cone 7, the fixed column 1 is in a right-straight hexagonal prism shape, three positioning holes 8 are formed in the prism side surface of the fixed column 1, and the three positioning holes 8 are distributed on the right-straight hexagonal.

As a further improvement of the technical scheme, a conical transition section 9 is arranged at the joint of the guide column 6 and the tapping part 3.

As a further improvement of the technical scheme, the outer surfaces of the tapping part 3, the guide post 6, the conical transition section 9 and the front cone 7 are provided with a boron nitride hard wear-resistant coating.

As a further improvement of the technical scheme, the thickness of the boron nitride hard wear-resistant coating is 23 mm.

As a further improvement of the above technical solution, the depth of the end of the chip groove 4 becomes gradually shallow from front to back.