Reverse spiral fluted tap

Abstract

The utility model provides a reverse spiral fluted tap, which relates to the technical field of taps, and comprises a cutting body and a plurality of spiral flutes, the cutting body comprises a cutting part and a calibration part, each spiral flute comprises a front flute and a rear flute, the front flute is connected with the rear flute, and the depth of the front flute is gradually increased from one end connected with the rear flute to the other end. According to the screw tap, the cutting part of the screw tap has large core diameter increment, so that in the tapping process, the cutting performance of the screw tap is guaranteed, the scrap iron rolling diameter is controlled, scrap iron is discharged forwards more smoothly, the better scrap control and discharge performance is achieved, and scrap clamping and tipping are not prone to occurring; moreover, the front groove and the rear groove are formed at a time, the effect of twice machining of the tip tap can be achieved, the tip tap has the good capability of discharging chips forwards, and the production cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of taps, in particular to a reverse spiral groove tap. Background Art

[0002] The chips of the currently commonly used reverse spiral groove taps are discharged downward, that is, toward the cutting edge. However, when the chip discharge is not smooth, the chips will be discharged upward, causing chip blockage. Moreover, when the chips are discharged upward, the tap may be squeezed, chipped, or even broken. To address the above defects, the present application is proposed. Utility Model Content

[0003] The utility model aims to provide a reverse spiral groove tap, which can control the diameter of the iron chips and discharge the chips forward more smoothly, thus avoiding problems such as chip jamming.

[0004] In order to solve the above problems, the utility model provides a reverse spiral groove tap, including a cutting body and a plurality of spiral grooves, the cutting body including a cutting portion and a calibration portion, the spiral groove is left-handed, the spiral groove includes a front groove and a rear groove, the front groove is connected to the rear groove, the depth of the front groove gradually increases from one end connected to the rear groove to the other end, so that the core diameter of the cutting portion gradually increases from the head end to the tail end.

[0005] The chip evacuation direction of the front flute is forward, similar to the tip tap.

[0006] Optionally, the bottom of the front groove forms an inclined surface, and the inclination angle ranges from 5° to 15°.

[0007] Preferably, the bottom angle of the front groove is 8°~10°.

[0008] According to an embodiment of the present invention, the depth of the rear groove does not change, that is, the depth of the rear groove is the same as the shallow depth of the front groove. It can also be said that the angle of the bottom of the rear groove does not change.

[0009] According to one embodiment of the present invention, the length of the front groove is greater than the length of the cutting part. The purpose of the inclination of the bottom of the front groove is to allow the iron chips to be discharged forward better. The cutting part is still involved in the cutting of the workpiece, and iron chips are still generated within the length of the cutting part. Therefore, the length of the front groove must be greater than the length of the cutting part.

[0010] According to an embodiment of the present invention, the length of the rear slot is greater than the length of the front slot, and the rear slot extends beyond the calibration portion.

[0011] According to one embodiment of the present invention, a coating is provided on the cutting body, that is, a coating is provided on the cutting portion, the calibration portion and the spiral groove surface, for improving the wear resistance and life of the tap. The coating can be a steam oxidation coating, a nitriding coating, a TiN (titanium nitride) coating, etc.

[0012] According to an embodiment of the present invention, the reverse spiral groove tap further includes a shank connected to the cutting body.

[0013] According to an embodiment of the present invention, the reverse spiral groove tap further includes a square tail connected to the shank.

[0014] According to an embodiment of the present invention, a cooling channel is provided inside the cutting body.

[0015] Furthermore, the cooling channel extends from the shank to the cutting body.

[0016] The beneficial effect of the present invention is that, by setting the front groove, the cutting part of the tap has a larger core diameter increment, thereby ensuring the cutting performance of the tap during the tapping process, and controlling the diameter of the iron chip curl, so that the iron chips can be discharged forward more smoothly, with better chip control and chip removal performance, and thus less likely to get stuck or break the edge; and, by forming the front groove and the rear groove at one time, the effect of twice processing the tip tap can be achieved, and the tip tap has a good ability to discharge chips forward, thereby reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0018] Figure 1 This is a schematic diagram of the overall structure of the reverse spiral groove tap;

[0019] Figure 2 This is the front view of the reverse spiral groove tap;

[0020] Figure 3 This is a schematic diagram of the dimensions of the front and rear slots. DETAILED DESCRIPTION

[0021] The following description is intended only to disclose the present invention and to enable those skilled in the art to implement the present invention. The embodiments described below are provided for illustrative purposes only, and those skilled in the art will readily appreciate other obvious variations. The basic principles of the present invention as defined in the following description may be applied to other embodiments, variations, improvements, equivalents, and other solutions that do not depart from the spirit and scope of the present invention.

[0022] [Example 1]

[0023] A reverse spiral groove tap, such as Figure 1 , including a shank 1, a square tail 2, a cutting body and a number of evenly distributed spiral grooves. In this embodiment, three groups of spiral grooves are provided.

[0024] This solution proposes a reverse spiral groove tap with a small helix angle, that is, the helix angle is small, generally 2°~20°, and the direction of the spiral groove is left-handed.

[0025] Specifically, the cutting body includes a cutting portion 3 and a calibration portion 4, the spiral groove includes a front groove 5 and a rear groove 6, the front groove 5 is connected to the rear groove 6, and the depth of the front groove 5 gradually increases from one end connected to the rear groove 6 to the other end.

[0026] like Figure 3 As shown, the bottom of the front groove 5 forms an inclined surface, and its inclined angle θ is 5°~15°, preferably 8°~10°.

[0027] Through the above-mentioned structural setting, the core diameter increment of the tap cutting part is large, such as Figure 3 The core diameter D1 at the end of the front groove 5 to the core diameter at the end where the front groove 5 is connected to the rear groove 6 gradually increases. The core diameter increment can be set to 2 mm or larger. Therefore, during the tapping process, the front groove 5 ensures the cutting performance of the tap and controls the diameter of the iron chip roll, so that the iron chips can be discharged forward more smoothly, avoiding problems such as chip jamming. The function of the rear groove 6 is to reduce friction resistance during the tapping process and allow the cutting fluid to enter completely, thereby achieving a better lubrication and cooling effect.

[0028] At the same time, the depth of the rear groove 6 does not change, or in other words, the angle of the bottom of the rear groove 6 does not change. Figure 3 , the core diameter D2 in the extension direction of the rear groove 6 does not change, so that the front groove 5 and the rear groove 6 can be formed at one time, but the effect of two-time processing of the tip tap can be achieved, which greatly reduces the production cost.

[0029] Preferably, the length L1 of the front groove 5 is greater than the length of the cutting part 3. The purpose of the inclination of the bottom of the front groove is to allow the iron chips to be discharged forward better, while the cutting part is still involved in the cutting of the workpiece and iron chips are still generated within the length of the cutting part, so the length of the front groove must be greater than the length of the cutting part.

[0030] Preferably, the length L2 of the rear slot 6 is greater than the length L1 of the front slot 5 , and the rear slot 6 extends beyond the calibration portion 4 .

[0031] Preferably, the cutting body is provided with a coating to improve the wear resistance and service life of the tap.

[0032] Example 2:

[0033] On the basis of Example 1, a cooling channel is provided inside the cutting body. Optionally, the cooling channel extends from the shank 1 or the square tail 2 to the cutting body for coolant to enter and circulate for cooling.

[0034] Those skilled in the art will appreciate that the embodiments of the present invention described above and shown in the accompanying drawings are intended only as examples and do not limit the present invention. The objectives of the present invention have been fully and effectively achieved. The functional and structural principles of the present invention have been demonstrated and illustrated in the embodiments. Any variations and modifications may be made to the embodiments of the present invention without departing from the principles described.

Claims

1. A reverse spiral groove tap, characterized in that: The invention comprises a cutting body and a plurality of spiral grooves, wherein the cutting body comprises a cutting portion (3) and a calibration portion (4), the spiral groove is left-handed and comprises a front groove (5) and a rear groove (6), the front groove (5) is connected to the rear groove (6), and the depth of the front groove (5) gradually increases from one end connected to the rear groove (6) to the other end.

2. The reverse spiral groove tap according to claim 1, characterized in that: The bottom of the front groove (5) forms an inclined surface, and the inclined angle range is 5° to 15°.

3. The reverse spiral groove tap according to claim 1, characterized in that: The depth of the rear groove (6) does not change.

4. The reverse spiral groove tap according to claim 1, characterized in that: The length of the front groove (5) is greater than the length of the cutting portion (3).

5. The reverse spiral groove tap according to claim 1 or 4, characterized in that: The length of the rear groove (6) is greater than the length of the front groove (5).

6. The reverse spiral groove tap according to any one of claims 1 to 4, characterized in that: The cutting body is provided with a coating.

7. The reverse spiral groove tap according to claim 6, characterized in that: The reverse spiral groove tap further comprises a shank (1).

8. The reverse spiral groove tap according to claim 7, characterized in that: The reverse spiral groove tap further comprises a square tail (2), wherein the square tail (2) is connected to the shank (1).

9. The reverse spiral groove tap according to claim 7 or 8, characterized in that: A cooling channel is provided inside the cutting body.

10. The reverse spiral groove tap according to claim 9, characterized in that: The cooling channel extends from the shank (1) to the cutting body.

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