CN2392944Y

CN2392944Y - Combined anti-return nut

Info

Publication number: CN2392944Y
Application number: CN 98241759
Authority: CN
Inventors: 田林
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-10-28
Filing date: 1998-10-28
Publication date: 2000-08-23
Anticipated expiration: 2008-10-28

Abstract

The utility model relates to a combined retaining nut, which comprises a lower main body 1 with a standard common internal thread 2, an upper main body 3 which is provided with an expanded common internal thread 5 and respectively provided with a fixing hole 6 and a lock opening hole 7 at both ends, and a soft thread sleeve 4. One end of the upper main body 3 with the lock opening hole 7 and one end of the lower main body 1 are made into complementary grooves which are used for abutting each other. Because of the interference fit between the soft thread sleeve 4 and a screw rod which is screwed in the soft thread sleeve 4, the retaining is realized by the radial pretightening force generated on the fit surface.

Description

A kind of combined type retaining nut

The utility model relates to a kind of combined type retaining nut.

Bolt and nut is widely used in every field as modal threaded fastener.This fastening piece has two outstanding features, that is: (1) fastening effect is realized by axial pre tightening force; (2) unscrewing is the inverse process of tightening, and required moment size required moment when tightening is basic identical.Because bolt and nut will be subjected to the complicated outside force effect in actual use, thus loosening voluntarily easily even come off, cause the hidden danger that might cause failure mechanisms.Human carrying out insistent exploration always, comprising the positive lock mechanism that adopts various non-self-lock mechanisms (as locating stud etc.) for improving threaded fastener.In recent years " self lock nut " at first succeeded in developing in China (patent No. 172789) introduced and become diameter flexible screw thread principle, rely on the radial tightening power between the bolt and nut to realize fastening effect, and unscrew and be not the simple inverse process of tightening, make its principle and reliable retaining performance with novelty, effectively prevented to become flexible, enlarged application and using scope day by day.But, because this nut has the screw thread in two kinds of apertures simultaneously, directly adding technology more complicated in man-hour, manufacturing efficiency is very low, has had a strong impact on applying of this advanced fastening piece.

The purpose of this utility model is, propose a kind of technology capability better, make simple novel retaining nut, thereby shorten the process-cycle, solve a difficult problem of producing in enormous quantities.

Technical solution of the present utility model is as follows:

The key that " self lock nut " is difficult to process is two sections screw thread close together, and wherein one of larger aperture section can't be shaped with the screw tap time processing.And will two sections screw thread time processing be shaped with screw tap, must strengthen the distance between these two sections screw threads, this inevitable again boundary dimension that increases nut greatly makes its forfeiture practicability.The utility model is according to the thinking of " split processing, be used in combination ", and the body of " self lock nut " is radially cut off, and is divided into two slotted nuts, and one of them has the common internal thread of standard, and another is equipped with flexible swivel nut.The pitch of two slotted nuts is identical, and diameter of thread difference can be processed with common process.When the accurate manufacturing of needs, two nuts can be drawn back certain distance along common axis, simultaneously to two taps, time processing is shaped with the special ladder screw tap of making; Two nut translations that will process at last reset, and are combined into one, and the flexible swivel nut of packing into is finished making.The retaining nut of processing and fabricating like this leaves the vestige of process interface in the side of body.

Advantage of the present utility model is as follows:

1. two sections screw thread time processing are shaped, and guarantee to obtain higher precision;

2. be convenient to realize the automation of processing and assembling increase substantially productivity;

3. swivel nut fixed hole and unlock hole can be in the drawings of preprocessing stage;

4. two slotted nuts can assemble and dispatch from the factory, and also can assemble in use, even use as single nut.

5. can be directly and the standard bolt adapted.

Provide detailed technology details of the present utility model below in conjunction with accompanying drawing, provide a better embodiment of the present utility model.Wherein, Fig. 1 shows general structure of the present utility model; The split structural representation that Fig. 2 is is in order to illustrate that embodiment is to the radially processing of the end face of " incision " formation of nut quilt.

See also Fig. 1.The utility model comprises body 1, upper body 3,4 three parts of flexible swivel nut down.On the internal surface of following body 1, done the common internal thread 2 of standard; Do the common internal thread 5 of expansion on the internal surface of upper body 3, two ends have fixed hole 6 and unlock hole 7 respectively.Flexible swivel nut 4 is actually a closed-coil spring, the stressed change of its diameter energy, and diameter increases when promptly being compressed moment, reduced when being subjected to stretch force moment.The pitch of the common internal thread 2 of standard, the common internal thread 5 that enlarges and flexible swivel nut 4 is identical and coaxial.Flexible swivel nut 4 is contained in the upper body 3, and the one end inserts fixed hole 6, and the other end is a free end.The free end elongation line of flexible swivel nut 4 is just in time by unlock hole 7.Upper body 3 has an end of unlock hole 7 and a wherein end of following body 1 to make complementary flute profile, two bodies can be docked be integral, and uses as complete retaining nut.During use, screw rod is screwed into by following body 1 one ends of retaining nut, 2 guiding function of the common internal thread of standard.The middle footpath of flexible swivel nut 4 is slightly less than the common internal thread 2 of standard, and the inboard and outside all is a screw thread, so it is a screw rod is again nut, and with screw rod (not drawing among the figure) be interference fit, with nut upper body 3 be Spielpassung, fitting surface between flexible swivel nut 4 and screw rod produces pretightening force radially.When screw rod is screwed into nut, the moment direction that screw rod applies flexible swivel nut 4 by friction be free end from swivel nut to fixed end, flexible swivel nut 4 makes expanded in diameter by compression, the frictional force between screw rod and the flexible swivel nut 4 reduces, screw rod is screwed into smoothly; When screw rod is back-outed nut, the power that screw rod applies flexible swivel nut 4 be fixed end from flexible swivel nut 4 to free end, flexible swivel nut 4 is subjected to the trend of stretched existing contracted diameter, this trend has greatly strengthened the radial tightening power of screw rod and swivel nut, effectively stop screw rod to be back-outed, realize retaining.

Therefore when adopting retaining nut and plain bolt to be used, tightening and unscrewing no longer is reciprocal process.Because flexible swivel nut 4 is single-ended fixing, thus it can only folk prescription to precession, can not oppositely revolve and move back.Even when axial pre tightening force is zero also is like this.In the time of the retaining nut need being backed out, to by unlock hole flexible swivel nut 4 be compressed with separating lock tool earlier, its diameter is increased, just can withdraw from screw rod.

Make this retaining nut, if it is in same body, process two sections different coaxial screw threads of pitch same diameter, very difficult on the technology.Because the restriction of the nut boundary dimension and the minimum number of turns, tool withdrawal groove 8 can not be done very widely, and two sections screw threads can't be shaped with the screw tap time processing.Secondly, unlock hole 6 is that the free end elongation line with flexible swivel nut 4 is an axis, and with the middle footpath general tangential of screw thread, with the outer side surface out of plumb of nut, the boring difficulty is bigger.Nut radially is divided into two-part, can solves the problem of this two aspect fully.Just provide an embodiment below, and specify down the connecting means of body 1 and upper body 3.

See also Fig. 2.Wherein,, a, b are respectively upper body worm's eye view and the plan view behind the flexible swivel nut of packing into, and c is following body plan view.The end face 9 of following body 1 is made complementary crenel shape groove with the end face 10 of upper body 3, in order to mutual butt joint.The end face 9 of butt joint can be made difformity with end face 10 according to assembly method is different mutually, and this example is selected the assembling of pressing method, thereby is designed to the cooperation of crenel shape groove.The benefit of doing like this is that they both can be used as independent slotted nut use, can dock again to be integral as the retaining nut and use.Therefore, the utility model also can be regarded the flute profile plain nut integrator with the different apertures of two identical pitch as.

The end face 10 of upper body 3 is designed to just in time by unlock hole 7, unlock hole 7 is changed in quality be groove, thereby the processing in hole is converted into the processing of groove, reduces difficulty of processing.Fixed hole 6 also can be converted into the groove on the other end equally.Through handling like this, body can become base with the pressing preprocessing up and down, then tapping of available dedicated equipment and assembling.During assembling, body common axis applied pressure overcomes the magnitude of interference between the crenel shape groove fitting surface about the edge, and both are pressed into one.

In single use and less demanding occasion, two bodies can process with common process respectively and the scene is used in combination.Concrete using method is: will descend body 1 bolt of screwing on slightly flat with the bottom land of following body end face 9 to the bolt end face earlier, and will patch with the upper body 3 and 1 pair of the following body of flexible swivel nut 4, and turn upper body 3 then, and whole nut together can be tightened.

The another kind of fit system of body butt joint is up and down: one of them makes dovetail groove, and another makes forked tail platform.During assembling, forked tail platform inserts dovetail groove under the radial force effect, thereby is combined into complete nut.

No matter it should be noted which kind of shape the mutual interface of body is up and down, if combination in use need be processed into combined interface Spielpassung or transition fit, otherwise should be adopted interference fit.

Also can adopt the flexible swivel nut 4 of material of other shaped cross, but its retaining effect may be relatively poor.

Claims

1 one kinds of combined type retaining nuts comprise body 1, upper body 3,4 three parts of flexible swivel nut down, it is characterized in that having done the common internal thread 2 of standard on the internal surface of following body 1; Do the common internal thread 5 of expansion on the internal surface of upper body 3, two ends have fixed hole 6 and unlock hole 7 respectively; Upper body 3 has an end of unlock hole 7 and a wherein end of following body 1 to make complementary flute profile, in order to mutual butt joint; The pitch of the common internal thread 2 of standard, the common internal thread 5 that enlarges and flexible swivel nut 4 is identical and coaxial; Flexible swivel nut 4 is actually a closed-coil spring, be contained in the upper body 3, the one end inserts fixed hole 6, the other end is a free end, the free end elongation line of flexible swivel nut 4 is just in time by unlock hole 7, the middle footpath of flexible swivel nut 4 is slightly less than the common internal thread 2 of standard, with screw rod be interference fit, with nut upper body 3 be Spielpassung.