CN2292933Y

CN2292933Y - Multisection expansion bolt

Info

Publication number: CN2292933Y
Application number: CN 96229220
Authority: CN
Inventors: 应文华
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-02-02
Filing date: 1996-02-02
Publication date: 1998-09-30
Anticipated expiration: 2006-02-02

Abstract

The utility model discloses a multiple-stage expansion bolt. Capable of generating two or more than two expansion surfaces jointing with a material body wrapping around the multiple-stage expansion bolt, the utility model can expands together with the wrapping material body and can be jointed with the wrapping material body into a whole. Instead of one expansion grasping point, a plurality of expansion grasping points are arranged for a single-stage expansion bolt and the wrapping material body which are manufactured and used for the current market, so that the defects that the single-stage expansion bolt can not bear the greater load which is axially stressed, and that after vibrated, the bolt is easy to loosen, and the fastening force of the bolt is reduced and ineffective, are overcome.

Description

The multistage expansion bolt

Technical field of fastening under the utility model.

Production on city's field boundary at present, the EXPANSION ANCHOR BOLTS of using all are the single-stage expansion bolts, and promptly EXPANSION ANCHOR BOLTS only has the gripping point that expands with the material bodies that contains rear in the EXPANSION ANCHOR BOLTS.When specifically object is inflated bolton, extend into rear in the EXPANSION ANCHOR BOLTS of concrete body or brick, Shi Kongzhong, along with tightening of nut, jag sleeve pipe in the EXPANSION ANCHOR BOLTS and bolt rear cone generation relative displacement make the jag sleeve pipe diverge in the hole, expand, and with the bolt cone, contain material bodies swelling in the lump, engage and be one.Yet EXPANSION ANCHOR BOLTS is highly very little cylndrical surface of EXPANSION ANCHOR BOLTS afterbody with the swelling surface of contact that contains material bodies.When object was fastening by the single-stage EXPANSION ANCHOR BOLTS, the suffered pulling force of screw rod equaled to contain the axial thrust load of material bodies to the tangential positive pressure of screw rod cone, and component increases its positive pressure and increases exponentially; Bolt containing material bodies material in the common use is generally all relatively poor, and at this moment material bodies just can not be born the expansive force of bolt to its generation, and the nut of EXPANSION ANCHOR BOLTS is foot tightly, twists to such an extent that excessive effect is run counter to desire; Therefore, in actual use, single-stage expansion bolt great majority are applied in object under the less demanding condition of fastening force, because it can not produce bigger axial tension load to it by carrying object.The equilibrium of forces primary condition is analyzed behind the single-stage expansion bolt stand under load, because the bore diameter of material bodies is than EXPANSION ANCHOR BOLTS nominal diameter big approximately 40%, contain material bodies and only screw rod cone afterbody is imposed on tangential positive pressure, EXPANSION ANCHOR BOLTS also just is subjected to the radial pressure on axial tension and the afterbody cone, and bolt just is difficult to balance external force to couple that it produced like this.Actual use condition also is like this, when vibration takes place or bolt is produced radially alternate load in object at work that fixed by the single-stage EXPANSION ANCHOR BOLTS, alternate load is easy to overcome frictional force between object and the material bodies and makes EXPANSION ANCHOR BOLTS grip point around it to make non-directional ground and move about, until containing stopping of material bodies hole end surface, moving about of bolt just changes direction, feasible in the course of time gripping point abrasion of containing material bodies or bolt cone, and expansive force descends, cause bolt looseness, fastening force lost efficacy.

The utility model multistage expansion bolt is for the expansion that increases EXPANSION ANCHOR BOLTS and containing material bodies grips point, improves the EXPANSION ANCHOR BOLTS axial carrying capacity, and bolt is designed in the purpose that is difficult under the working state of being shaken or under the alternate load situation becoming flexible.The multistage expansion bolt can have secondary or the above expansion mating face of secondary, and its structure, profile are as shown in the figure.Its basic role principle grows up on single-stage expansion bolt basis, is example for the ease of being briefly described problem existing with the compound expansion bolt.The multistage expansion bolt is made up of cone screw rod 1, jag sleeve pipe 2, cone packing 3, jag sleeve pipe 4, neck ring 5, packing ring 6, spring washer 7 and hexagon nut 8.Cone packing 3 and neck ring 5 equal kinks are on cone screw rod 1, when object during by the multistage expansion bolton, cone screw rod 1 produces axial tension, makes cone screw rod 1 promote jag sleeve pipe 2, cone packing 3, jag sleeve pipe 4 and neck ring 5 in succession to top offset to top offset.Because neck ring 5 fastened objects limit can not be to top offset, also hinder jag sleeve pipe 2 and the jag sleeve pipe of desiring to top offset 4 simultaneously, make it in compressive stress of inner generation separately; The thrust that cone screw rod 1 acts on jag sleeve pipe 2 can resolve into and promote jag sleeve pipe 2 to the component of top offset with make the component of jag sleeve pipe 2 in the radial expansion of jag end; Similarly cone packing 3 thrust that acts on jag sleeve pipe 4 also can resolve into component that makes 4 radial expansions of jag sleeve pipe and the component that axially makes progress.Along with tightening of nut 8, cone screw rod 1 axial tension stress increases gradually, correspondingly jag sleeve pipe radial expansion component also increases thereupon, when component to be expanded is increased to a certain degree, cone screw rod 1 and jag sleeve pipe 2, cone packing 3 and jag sleeve pipe 4 these two sections expansion mating faces just with contain material bodies on every side and be expanded to one in the lump.In like manner the expansion principle of three grades or quadruple expansion bolt too.

In order to strengthen the purchase capabilities of 3 pairs of cone screw rods 1 of cone packing, axial direction at cone packing 3 has an opening slot, be convenient to cone packing 3 radial contraction, when treating that bolt contains material bodies to jag sleeve pipe generation reaction force, can make cone packing 3 grip cone screw rod 1 tightly.

The external diameter of neck ring 5 is the same big with the aperture that bolt contains material bodies; make the multistage expansion bolt increase a sliding fulcrum at the intersection that exposes the material bodies end face; the flexural stress that can change cone screw rod 1 when cone screw rod 1 is subjected to the radial effect power of fastened object is a shearing stress, can protect screw rod to be difficult for loosening characteristics simultaneously under the condition of being shaken.

In order to prevent skidding may to occur at 8 pairs of cone screw rods 1 of fastening hexagon nut, be provided with the groove that the hexagonal groove of inner hexagon spanner or in-line, cross screw are criticized at the top end of cone screw rod 1 for this reason, be used to stop cone screw rod 1 slipping.

The utility model multistage expansion bolt manufacturing technology standard can be with reference to existing single-stage expansion bolt production technical standard, and manufactured materials can be selected Q235 or 20 steel for use.

Claims

1. multistage expansion bolt, comprise cone screw rod 1, jag sleeve pipe 2, cone packing 3, jag sleeve pipe 4, neck ring 5, packing ring 6, spring washer 7 and hexagon nut 8 compositions, it is characterized in that: the multistage expansion bolt of rear in extending in concrete body or the rigid material body opening, along with tightening of nut 8, two or more expansions mating face can take place with the material bodies that contains on every side in cone screw rod 1 and jag sleeve pipe 2, cone packing 3 and jag sleeve pipe 4, and contain material bodies swelling in the lump with bolt, engage and be one.

2. multistage expansion bolt according to claim 1 is characterized in that: the top end that is positioned at cone screw rod 1 is provided with the groove that the hex slot of Allen wrench or in-line, cross screw are criticized, and is used to stop cone screw rod 1 skid.