CN201034105Y

CN201034105Y - Self-tapping locking screw

Info

Publication number: CN201034105Y
Application number: CNU2007200682491U
Authority: CN
Inventors: 李根荣; 陈刚; 薛李激; 凌勇; 陆知明; 江瑶琪
Original assignee: Shanghai Fastener And Welding Material Technology Institute
Current assignee: Shanghai Fastener And Welding Material Technology Institute
Priority date: 2007-03-28
Filing date: 2007-03-28
Publication date: 2008-03-12
Anticipated expiration: 2017-03-28

Abstract

The utility model discloses a self-tapping and locking screw. The utility model is characterized in that a triangular cutting groove is arranged at the circumference of the screw thread; the cutting groove is provided with a cutting face and a locking face; the tangent of the cutting face points to the centre of the circumference of the screw thread. The utility model has the advantages that the self-tapping and locking screw with small moment and large locking force can force large resistance torque, which can effectively prevent the screw from loosing.

Description

Self-tapping lock screw

Technical field

The utility model relates to tapping screw, relates in particular to a kind of self-tapping lock screw.

Background technique

In order to prevent Fastener products to be installed in the vibration environment loosening easily phenomenon, industrially on the fastening object of needs, process screw thread usually in advance or use nut, these programs have been removed in the appearance of self-tapping lock screw from.Present self-tapping lock screw has the regular screw threads (see figure 1) of arc triangle section, connected piece need not end screw thread and just can shoot automatically, and provides anti-loose and the against shock effect, when connecting, screw also can be in the thread Pilot hole of connected piece the tapping internal thread, formation is threaded.But the tapping form of this v thread is a thread-rolling screw, and the moment of tap out is big, and owing to have only three ribs, coupling mechanism force is less relatively, is not suitable for being used for slab or harder, frangible material.

The model utility content

The technical problems to be solved in the utility model provides a kind of self-tapping lock screw, can more effectively prevent screw loosening.

In order to solve the problems of the technologies described above, the utility model self-tapping lock screw is provided with the cutting flutes of triangle on the circumference of its screw thread, and this cutting flutes has cutting edge face and locking face, and the tangent line of described cutting edge face points to the center of circle of screw thread circumference.

Self-tapping lock screw of the present utility model is compared with the self-tapping lock screw of existing v thread, and it is littler to be screwed into moment, and coupling mechanism force is bigger, can form a very big resistive torque and prevent screw loosening.

Description of drawings

Below in conjunction with the drawings and specific embodiments the utility model is described in further detail.

Fig. 1 is the v thread sectional drawing of existing self-tapping lock screw;

Fig. 2 is the form figure of the utility model self-tapping lock screw;

Fig. 3 is the sectional drawing of the utility model self-tapping lock screw under actual conditions;

Fig. 4 is the planimetric map of the utility model self-tapping lock screw.

Embodiment

As shown in Figure 2, self-tapping lock screw of the present utility model is to add man-hour at its screw thread, cut the cutting flutes that sets out triangle on the circumference of this screw thread, this cutting flutes has cutting edge face 1 and locking face 2, and the tangent line of described cutting edge face 1 points to the center of circle of screw thread circumference.

In an embodiment of the present utility model, the height of described cutting flutes is the distance of major diameter of thread 3 to the core diameter of thread 4, described cutting edge face 1 is vertical with locking face 2 so that accurately calculate spiral shell embryo size, and when processing mold also control size accurately; The quantity of described cutting flutes is preferably six, and these six triangle cutting flutes are to cut out (see figure 2) in the first-class angle of screw thread circumference.

As shown in Figure 3, self-tapping lock screw of the present utility model in use, described cutting edge face plays the effect of tap, on matrix 5, cut out screw thread, because it is a cutting, metal streamline is destroyed, and therefore the extrusion moulding screw thread of the relative v thread of cutting force of described cutting edge face is much smaller.Screw of the present utility model during tapping, because parent metal is a plasticity, has a decrement in matrix 5, after the screw tap out was in place, the parent metal resilience made the size of the big footpath of screw less than the big footpath of screw thread, connects to form.Run into vibration when this is connected, when screw has the tendency of back-out, because the big footpath of screw is less than the big footpath of screw thread, obtain a very big resistive torque and prevent screw loosening, and owing to evenly be provided with six triangle grooves on the screw cross section, so can obtain six resistive torque simultaneously, three resistive torque of v thread more can stop the loosening of screw relatively.

Self-tapping lock screw of the present utility model can be designed to structure as shown in Figure 4, comprises screw rod and screw head, and screw front end is equipped with the tapered guide part, and screw head can be made into hexagon head, cross recess coiled hair, interior hexagonal flower shape cylinder is first-class.Because screw of the present utility model adopts stainless steel to make, and heat-treats with vacuum furnace in the production technology later stage, makes this screw not only have high corrosion resistance, and can guarantee the intensity and the rapidity that is connected of connection.

Claims

1. self-tapping lock screw is provided with the cutting flutes of triangle on the circumference of its screw thread, this cutting flutes has cutting edge face and locking face, it is characterized in that, the tangent line of described cutting edge face points to the center of circle of screw thread circumference.

2. self-tapping lock screw as claimed in claim 1 is characterized in that, the height of described cutting flutes is the distance of major diameter of thread to the core diameter of thread.

3. self-tapping lock screw as claimed in claim 1 or 2 is characterized in that, described cutting edge face is vertical with locking face.

4. self-tapping lock screw as claimed in claim 1 or 2 is characterized in that, described cutting flutes is six.

5. self-tapping lock screw as claimed in claim 3 is characterized in that, described cutting flutes is six.

6. self-tapping lock screw as claimed in claim 4 is characterized in that, described cutting flutes is six triangular grooves that the first-class angle of screw thread circumference cuts out.

7. self-tapping lock screw as claimed in claim 5 is characterized in that, described cutting flutes is six triangular grooves that the first-class angle of screw thread circumference cuts out.