CN2202606Y

CN2202606Y - Oblique edge tap

Info

Publication number: CN2202606Y
Application number: CN 94235543
Authority: CN
Inventors: 汲伟民
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-10-14
Filing date: 1994-10-14
Publication date: 1995-07-05
Anticipated expiration: 2004-10-14

Abstract

The utility model relates to an oblique edge screw tap, which belongs to the technical field of thread cutting tools. The oblique edge screw tap solves the disadvantages that an ordinary screw tap has difficult chip discharge, and chips are easy to be squeezed. The oblique edge screw tap is still composed of a cutting part, a guiding part and a tail handle. Differing from the ordinary screw tap, the spiral angle of the chip flute of the oblique edge screw tap or an included angle formed by the chip flute and the axial lead of the screw tap is between 12 DEG and 20 DEG with a direction opposite to threads. The oblique edge screw tap can be widely used for machining threads to replace the existing ordinary screw taps.

Description

Oblique edge tap

The utility model is a kind of oblique sword screw tap, and it belongs to the thread-cutting tool technical field, and it has the cutting tip of taper, the targeting part and the caudal peduncle of garden cylindricality, has chip pocket thereon, and chip pocket is helicla flute or straight trough.

Three swords of using in the current production or multiple-cutting-edge screw tap, the chip pocket that has on it is straight trough or helicla flute, the angle that chip pocket is become with the screw tap axial line or the helical angle of groove equal the lift angle of screw tap screw thread, the number of degrees are very little, because selecting for use of this parameter is unreasonable, cause in the processing chip removal unfavorable, want continuous reverse rotation in the processing, so that chip breaking and chip removal are pulled even if still often occur attacking the surface of making screw thread like this.In addition, also influenced the raising of production efficiency.When material that these defectives are lower in workhardness, plasticity, toughness are bigger such as aluminium, copper, stainless steel etc., performance particularly outstanding.

The purpose of this utility model just provides a kind of machining screw surface quality height, production efficiency height, screw tap that durability is high.

The utility model is achieved in that it still has the targeting part and the caudal peduncle of the cutting tip of taper, garden cylindricality, have chip pocket thereon, chip pocket is helicla flute or straight trough, the cone angle of its cutting tip and length, the design of targeting part and caudal peduncle part, and the choosing with generally screw tap is identical of design of the groove number of chip pocket and flute profile and angle, front and back, can determine according to the Tool Design handbook.This screw tap is with the difference of general screw tap: its chip pocket or be 12 °-20 ° at the chip pocket of the cutting tip helical angle on the cylinder of garden or the angle that become with the screw tap axial line outside screw tap at least, the direction of chip pocket is opposite with the direction of screw tap screw thread.

This screw tap is because the helical angle or the straight trough of chip pocket are big with the angle that the screw tap axial line is become, thereby following two advantages are arranged: the one, smear metal is successfully flowed to green surface, can not form and squeeze the quality that bits influence machined surface, cutting fluid also can flow into smoothly, fully play lubricated and cooling effect, machined surface quality is improved; Simultaneously work in-process also need not to reverse so that chip breaking and move back bits has so also improved the efficient that comes into force; The 2nd, because the increasing of angle is distributed in than on the more cutting edge of general screw tap same cutting depth, the single-blade thickness of cutting reduces, the smear metal attenuation, and tool life improves, and the life-span prolongs.So this screw tap has machined surface quality height, production efficiency height, characteristics that durability is high.

Fig. 1 is an outside drawing of the present utility model;

Fig. 2 cuts shape figure for end face of the present utility model.

Below in conjunction with accompanying drawing the utility model is described in detail.

Screw tap is divided into the cutting tip 1 of taper on total length as can be seen from Figure 1, and the targeting part 2 of garden cylindricality and caudal peduncle 3 have chip pocket 4 thereon.Chip pocket 4 is a helicla flute, and its helical angle is θ.As can be seen from Figure 2, this is a three-flute screw tap.The flute profile of chip pocket can be single garden arc, two straight lines, one garden arc or two garden arcs, one linear, and the concrete size of relevant flute profile can be chosen by the Tool Design handbook.The screw thread of screw tap is dextrorotation, and chip pocket is left-handed.

This routine flute profile is two garden arcs, one linears, and its concrete flute profile is of a size of: fuse diameter d=0.5D, cutter lobe width b=0.34D, R ₁=0.56R, R=0.4D, anterior angle γ=7 °, D is the screw tap external diameter.

When being the screw tap of M16, D is 16mm, and θ is 20 °;

When being the screw tap of M12, D is 12mm, and θ is 16 °;

When being the screw tap of M10, D is 10mm, and θ is 12 °.

Claims

1, a kind of oblique sword screw tap, it has the cutting tip of taper, the targeting part and the caudal peduncle of garden cylindricality, have chip pocket thereon, chip pocket is helicla flute or straight trough, it is characterized in that: chip pocket or be 12 °-20 ° in the chip pocket of the cutting tip helical angle on the cylinder of garden or the angle theta that become with the screw tap axial line outside screw tap at least, the direction of chip pocket is opposite with the direction of screw tap screw thread.