LOCKING NUT

Abstract: Locking nut for nut-and-bolt system, where the locking nut consists of two sections, a main nut and a lock nut. The lock nut is tightened on to the main nut and, due to the thread's conicity or the angle of the thread's profile, the friction action of the main nut against the bolt will, by tightening of the lock nut, increase and the main nut will therefore lock itself on to the bolt.

Description: LOCKING NUT This invention relates to a nut which can be locked on to a bolt. There is to-day on the market a number of systems, the purpose of which is to increase the friction between nut and bolt or between nut and support. Such systems are "Ny-loc" nuts, castellated nuts, lock washers, etc. All these systems have in common that none markedly increases the torque which is necessary to loosen the nut from the bolt. With the locking nut according to this invention, the user can himself adjust how well the nut will sit, by choosing the design and the stud torque. The locking nut (M) consists of a main section (M ) and a lock section (M ) , where (M ) is screwed on to (M ) . See figure 1. The outer thread (2) on (M ) and the inner thread on (ML) are .made conical, and when (ML) is tightened on to (M ) a clamping force is exerted against a bolt which is driven through (M ) . The friction obtained between the nut (M ) and the through bolt is dependent on the stud torque. In order to obtain a higher locking force with a lesser stud torque, the outer threaded part of the main section (M ) can be axially slotted. An alternative is to make the thread between the nuts parallel and to tighten (M ) home on to (ML). Then, by tightening with the desired torque, the angle between the threaded faces will cause clamping against the bolt. In figure 1 is shown a locking nut with conical thread, in locked position, while figure 2 shows the same position with parallel thread. Figure 3 illustrates examples of main nuts with through slots. The invention has several advantages over known methods. No alteration of the bolt is required, as for example drilling of holes or cutting of slots. The bolt is not damaged by the locking process. The nut can be locked after tightening of the bolt, or it can be locked without the bolt being tightened, etc.

Claims: AMENDED CLAIMS [received by the International Bureau on 27 September 1986 (27.09.86) original claims 1 -4 replaced by new claim 1 (1 page)] 1. Locking nut (M) with main nut (M1 ) which has an inner thread (1) to fit the bolt (S), and on parts of its outer periphery has a cylindrical thread (2) which is axially slotted through (3), on which a lock nut (M2) is screwed and tightened home against the main nut (M1 ) , c h a r ac t e r i z e d in that the thread's (2) profile is chosen so as to exert a clamping force against the bolt (S) by the torque action of the lock nut (M2).

Inventors: KOLVEREID HARALD, KOLVEREID, HARALD
Applicants: KOLVEREID HARALD, KOLVEREID, HARALD
Application year: 1986
Main classification: F16B39
IPC codes: F16B39