High-precision perpendicularity screw cone

Abstract

A high-precision perpendicularity screw tap belongs to the technical field of thread machining and comprises a screw tap body, a clamping portion, a forming cutting portion and a conical cutting portion which are integrally formed are arranged on the screw tap body, chip grooves are formed in the forming cutting portion and the conical cutting portion, and a guide portion which is integrally formed is arranged at the front end of the screw tap body. The guide part is a cylindrical guide part, and the outer edge of the front end of the cylindrical guide part is provided with a chip groove and a chamfer; the screw tap has the beneficial effects that before the conical cutting part enters the inner hole of the nut semi-finished product, the integral axial lead of the screw tap is overlapped with the axial lead of the nut semi-finished product, so that the screw tap is vertical to the end surface of the nut, the perpendicularity of internal threads tapped in the nut is consistent, deflection is avoided, and the service life of the nut is prolonged. Therefore, the meshing surface of the nut thread and the screw thread is complete, and the stability of the nut fastened on the screw is better.

Description

Technical Field

[0001] The invention belongs to the technical field of thread processing, in particular to a high-precision verticality screw tap. Background Art

[0002] In the cold forging process for nuts, the raw material undergoes multi-die stamping, deformation, and punching to complete the semi-finished nut. Finally, the semi-finished nut is tapped through the inner ring wall to create the finished product. Currently, tapping is commonly performed using a corkscrew. Corkscrews can produce a variety of medium and small internal threads. Their simple structure and ease of use allow them to be operated manually or on machine tools, making them widely applicable.

[0003] Tapping is a cutting process that requires relatively high precision. The screw tap is almost buried in the workpiece for cutting. If the perpendicularity of the screw tap and the end face of the nut cannot be guaranteed in advance, the internal threaded hole obtained after tapping will be skewed. When using a nut with a skewed internal thread, one side of the screw will be tightened while the other side will be loose, making it difficult for the nut and the screw to be securely fastened. The existing method of ensuring the perpendicularity of the end face of the screw tap and the nut is to fix the nut and the screw tap with a clamping device. However, since the cone pattern of the existing screw tap is directly at the front end, the angle at which the screw tap contacts the inner hole of the nut is the same, which makes the internal thread not vertical and easily skewed. At the same time, due to the offset generated during tapping, the screw tap is unevenly stressed, which can easily lead to the phenomenon of the screw tap breaking. Utility Model Content

[0004] The technical problem to be solved by the present invention is to provide a screw tap with a guide column in order to solve the above problems.

[0005] To ensure the verticality of the screw taper and the nut end face, the occlusal surface of the nut thread and the screw thread is complete, and the stability of the nut after being tightened on the screw is better.

[0006] In order to solve the above technical problems, the technical solution adopted by the utility model is a high-precision verticality screw tap.

[0007] It includes a screw tap body, and the existing screw tap body is provided with an integrally generated clamping part, a forming cutting part and a tapered cutting part, and the forming cutting part and the tapered part are provided with a chip groove, wherein the clamping part is used to clamp the screw tap on the clamping tooling, the forming cutting part is used to cut and tap to obtain the required internal thread, the tapered cutting part is used to gradually feed the forming cutting part into the inner hole position of the nut semi-finished product, and the chip groove is used to discharge waste chips generated during cutting; the present invention is provided with an integrally generated guide part at the front end of the screw tap body, that is, a guide part is provided at the front end of the tapered cutting part.

[0008] The guide portion is a cylindrical guide portion corresponding to the inner hole of the nut.

[0009] The front end outer edge of the cylindrical guide portion is chamfered.

[0010] The length of the cylindrical guide portion is equal to 0.01-3 times the length of the nut, and the nut can be a standard nut.

[0011] It can also be a non-standard nut; the diameter of the cylindrical guide portion is equal to 98%-100% of the diameter of the inner ring wall of the nut when it is not tapped.

[0012] Preferably, the length of the cylindrical guide portion is equal to 1.0 times the length of the nut, and the diameter of the cylindrical guide portion is equal to 99.99% of the diameter of the inner ring wall of the nut when not tapped.

[0013] The minimum diameter of the chamfer is equal to or less than 80% of the diameter of the inner ring wall of the nut when not tapped.

[0014] The beneficial effects of the utility model are

[0015] (1) The cylindrical guide part can ensure that the overall axis of the screw taper coincides with the axis of the nut semi-finished product before the conical cutting part enters the inner hole of the nut semi-finished product, which can ensure that the screw taper and the inner hole of the nut are perpendicular. In this way, the internal thread tapped in the nut is vertical and will not be deflected, so that the nut thread and the screw thread bite surface are achieved.

[0016] 100% integrity, better stability after the nut is tightened on the screw.

[0017] (2) Since the screw tap is vertically inserted into the nut end face into the inner hole of the nut, the tapping part of the screw tap is evenly stressed.

[0018] Can increase the service life of the screw tap.

[0019] (3) The chamfer ensures that the front end of the screw tap can smoothly enter the inner hole of the semi-finished nut before tapping. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the overall structure of the high-precision verticality screw tap of the utility model.

[0021] Figure 2 This is a schematic diagram of the structure of the utility model for ensuring verticality of the high-precision verticality screw tap before and during tapping.

[0022] Figure 3 It is a structural schematic diagram of an existing corkscrew.

[0023] In the figure: 1. Screw cone body, 2. Clamping part, 3. Forming cutting part, 4. Conical cutting part, 5. Chip removal groove, 6.

[0024] Guide, 7. Cylindrical guide, 8. Chamfer, 9. Semi-finished nut, 10. Inner ring wall of the nut before tapping. DETAILED DESCRIPTION

[0025] The present invention will be further described below with reference to the embodiments.

[0026] The utility model manufactures a high-precision verticality screw tap, such as Figure 3 As shown, the existing screw tap includes a screw tap body 1, which is provided with an integrally formed clamping portion 2, a forming cutting portion 3 and a tapered cutting portion 4. The forming cutting portion 3 and the tapered cutting portion 4 are provided with a chip removal groove 5, wherein the clamping portion 2 is used to clamp the screw tap on the clamping fixture, the forming cutting portion 3 is used to cut the inner ring wall of the semi-finished nut for tapping to obtain the required internal thread, the tapered cutting portion 4 is used to gradually feed the forming cutting portion 3 into the inner hole position of the semi-finished nut to complete the nut thread production, and the chip removal groove 5 is used to discharge the waste chips generated during cutting; when this type of screw tap is tapping, the angle at which it contacts the inner hole of the semi-finished nut is what it is, and it will not automatically adjust, making it difficult to ensure that the internal thread is straight and prone to deflection. At the same time, due to the uneven force applied when the screw tap is tapping into the inner hole of the nut, the screw tap is prone to breakage.

[0027] In this embodiment, an integral guide portion 6 is provided at the front end of the corkscrew body 1. Figure 1 That is, a guide portion 6 is provided at the front end of the tapered cutting portion 4. The guide portion 6 is a cylindrical guide portion 7 and is provided with a chip removal groove.

[0028] Furthermore, a chamfer 8 is provided on the outer edge of the front end of the cylindrical guide portion 7 .

[0029] The length of the cylindrical guide portion 7 is equal to 0.01-3 times the length of the nut, and the diameter of the cylindrical guide portion 7 is equal to 98%-100% of the diameter of the inner ring wall 10 of the nut when not tapped.

[0030] In this embodiment, the length of the cylindrical guide portion 7 is set to be equal to 1.0 times the length of the nut, and the diameter of the cylindrical guide portion 7 is set to be equal to 99.99% of the inner diameter of the inner ring wall 10 of the nut when not tapped.

[0031] The minimum diameter of the chamfer 8 is made equal to or smaller than 80% of the diameter of the inner ring wall 10 of the nut when not tapped.

[0032] like Figure 2 As shown, before tapping (a), just slightly align the screw tap body 1 with the nut semi-finished product 9.

[0033] After the corkscrew body 1 enters the inner ring wall of the semi-finished nut 9 (b), the cylindrical guide portion 7 can be automatically adjusted so that the corkscrew body 1 and the end face of the semi-finished nut 9 remain perpendicular and stably enter the inner hole, so that a finished nut with consistent thread verticality can be obtained.

Claims

1. A high-precision verticality screw tap, comprising a screw tap body (1), wherein the screw tap body (1) is provided with an integrally formed clamping portion (2), a forming cutting portion (3) and a tapered cutting portion (4), wherein the forming cutting portion (3) and the tapered cutting portion (4) are provided with a chip removal groove (5), characterized in that The front end of the corkscrew body (1) is provided with an integrally formed guide portion (6).

2. The high-precision verticality screw tap according to claim 1, characterized in that The guide portion (6) is a cylindrical guide portion (7).

3. The high-precision verticality screw tap according to claim 2, characterized in that The cylindrical guide portion (7) is provided with a chip removal groove (5).

4. The high-precision verticality screw tap according to claim 2, characterized in that The front outer edge of the cylindrical guide portion (7) is provided with a chamfer (8).

5. The high-precision verticality screw tap according to claim 3, characterized in that The length of the cylindrical guide portion (7) is equal to 0.01-3 times the length of the nut, and the diameter of the cylindrical guide portion (7) is equal to 98%-100% of the diameter of the inner ring wall (10) of the nut when not tapped.

6. The high-precision verticality screw tap according to claim 4, characterized in that The length of the cylindrical guide portion (7) is equal to 1.0 times the length of the nut, and the diameter of the cylindrical guide portion (7) is equal to 99.99% of the diameter of the inner ring wall (10) of the nut when not tapped.

7. The high-precision verticality screw tap according to claim 4, characterized in that The minimum diameter of the chamfer (8) is equal to or less than 80% of the diameter of the nut inner ring wall (10) when not tapped.

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