CN2230199Y - Tap - Google Patents

Abstract

The utility model relates to a tap, which is characterized in that a zero-degree back angle part connected with a cutting edge is kept with 0.5-2 mm, and the rest back angle parts are all abraded into the angles between 20 DEG and 30 DEG. The tap has the advantages of more than quintuple work efficiency, large chip containing space as compared with the existing taps, little friction resistance, easiness for tapping and long service, and the tap is not easy to be broken.

Description

A kind of screw tap

The utility model relates to the screw tap technology, belongs to internal thread machining cutter class.

Screw tap is the cutting cutlery of using in order to the system screwed hole in the machinery manufacturing industry, this cutting cutlery material hardness height, and fragility is bigger, in making tapping operating process by hand usually, because cutting load is heavier, and manual operations is firmly uneven, and the accident that screw tap is twisted off often has generation, the screw tap that is twisted off is stuck in and is difficult in the hole taking out, even cause product rejection, not only loss screw tap, and inefficiency, both influence production, also caused economic loss.

Through researching and analysing, the reason that causes screw tap to be twisted off is:

1, during screw tap was made, thermal treatment quality was poor, has hardening flaw;

2, tapping method is improper, and is firmly unreasonable;

3, the angle part is too big behind 0 ° on the existing screw tap, certainly leads to friction during tapping, and cutting resistance is big, and screw tap is easily blocked by built-up edge.

The reason of first and second point is not difficult to award solution by method respectively, and just showing thirdly, reason proposes following solution:

Keep 0.5-2mm with angle part after cutting edge contains 0 ° that connects mutually, (big screw tap is got big value, and little screw tap gets the small value), all the other angle parts, back all reconditioning become 20-30 degree angle.

Fig. 1 is the utility model organigram, and wherein A-A is the AA profile.

Embodiment: get tool steel or alloy tool steel (as T12A), be processed into screw tap by Fig. 1 structure, particularly the angle part keeps 0.5-2mm after 0 °, and all the other back angle part reconditionings become 20-30 degree angle.

The utility model with the advantage that existing screw tap is compared is:

Under the screw tap condition of same model as to attack the material of system also identical, this reality Bigger than existing screw tap chip space with Two-end Tap Applied, frictional resistance is little, during tapping Lighter, can improve work efficiency more than five times, and be difficult for being fractureed, the life-span Long, good in economic efficiency.

Claims (1)

1, a kind of screw tap is characterized in that:

Keep 0.5-2mm with angle part after cutting edge contains 0 ° that connects mutually, (big screw tap is got big value, and little screw tap gets the small value), all the other angle parts, back all reconditioning become 20-30 degree angle.