WO2016137000A1

WO2016137000A1 - Structure for locking nut tightened on bolt

Info

Publication number: WO2016137000A1
Application number: PCT/JP2016/055959
Authority: WO
Inventors: 良三太田
Original assignee: 良三太田
Priority date: 2015-02-25
Filing date: 2016-02-18
Publication date: 2016-09-01
Also published as: JP5835701B1; JP2016156488A

Abstract

An upper member (13) is superposed, through a bolt hole (14), onto the top of a lower member (15) in which a bolt (1) is implanted, a truncated cone section (5) is provided at the upper portion of a fastening nut (3) screwed onto the upper member, vertical division grooves (7) are provided in the radial direction in 4-6 locations in the truncated cone section, and trapezoidal thin plates (8) are somewhat firmly press-fitted into all of the vertical division grooves. The fastening nut is firmly screwed onto the bolt, after which a locking nut (11) is screwed on from above, thereby pressing in the trapezoidal thin plates (8) fitted into the vertical division grooves by means of truncated-cone-shaped holes (12) in the lower portion of the locking nut, and causing the trapezoidal thin plates to bite into the crests of the male thread (2) of the bolt, thus preventing the fastening nut from rotating with respect to the bolt.

Description

Locking structure for nuts tightened on bolts

The present invention is a method for preventing loosening of a nut tightened in a coarse screw bolt that requires a strong tightening force.

As a method of fixing the nut to the bolt to prevent loosening, there is a method of opening a common hole that penetrates the nut and bolt, and fixing by pushing the split pin here, but this drilling is sometimes troublesome because it may be done on site In addition, there is a disadvantage that it does not match when the nut is tightened again after unscrewing, and the nut used when pressing the rolling bearing is a fine screw, it can not withstand a heavy load, and the shaft has a groove It requires machining and the number of folds on the tongue of the washer is limited. Therefore, it is unsuitable to use this method for coarse threaded bolts, and it is a double nut type locking device to increase the frictional force of the thread surface. There are nuts, but this effect is unknown.

The present invention loosens a trapezoidal thin plate of a tightening nut with a special structure without biting or drilling a coarse screw bolt that requires a strong tightening force in advance, and bites it into the male thread of the bolt with a locking nut. Make sure to prevent the nut from loosening.

A truncated cone part 5 is provided at the upper part of the tightening nut 3, and a trapezoidal thin plate 8 is press-fitted into the radial longitudinal grooves 7 at four to six locations of the truncated cone part. By screwing the nuts 11 on top of each other, the trapezoidal thin plate is loosened and pushed out toward the bolt by the inner peripheral inclined surface of the conical hole 12 of the locking nut, and the inner end surface 9 of the trapezoidal thin plate bites into the top of the male screw 2 of the bolt. This prevents the tightening nut from rotating.

The implementation of the present invention makes it possible to reliably prevent loosening of nuts after tightening nuts into coarse screw bolts, and to prevent dropping of nuts such as railway vehicles with severe vibration.

As an example of an embodiment of the present invention, a longitudinal sectional view of a state in which a locking nut is fastened to a tightening nut to a bolt Plan view of FIG. Side view of FIG. Front view of the wedge-shaped piece incorporated in FIGS. 1, 2 and 3 Plan view of FIG. Side view of FIG.

A truncated cone part 5 is provided at the upper part of the tightening nut 3, and four to six radial narrow grooves 7 in the radial direction are provided in the truncated cone part. And the trapezoidal thin plate 8 hardened | cured by quenching etc. as shown in FIG. 6 is slightly press-fitted. The thickness of the trapezoidal thin plate is about 1 to 3 mm, the length thereof is the same as the length of the longitudinal groove of the truncated cone part, and the inclination angle of the outer end face 10 is made the same as the inclination of the truncated cone part 5. When the two trapezoidal sheets are inserted into the two vertical grooves facing each other in the truncated cone part, the inner end face 9 of the two trapezoidal sheets is brought into close contact with the top of the male screw 2 of the bolt, and the outer end face of the two trapezoidal sheets By slightly projecting 10 from the outer peripheral surface of the truncated cone portion, the outer end face 10 of the trapezoidal thin plate is conically shaped as a loosening stop nut by overlapping the tightening nut and screwing the loosening stop nut 11 into the bolt. The inner end surface 9 is pushed by the inner surface of the hole 12 and protrudes to the top of the male screw 2 of the bolt by the dimension that has been protruded, and the rotation of the tightening nut is prevented. It is not necessary to make the food allowance too large After returning the locking nut, there is no risk of failure when returning the tightening nut, and there is no risk of reducing the strength of the bolt.

DESCRIPTION OF SYMBOLS 1 ... Bolt 2 ... Male screw of bolt 3 ... Tightening nut 4 ... Female screw of tightening nut 5 ... Frustum part 6 of a fastening nut 6 ... Circumferential groove of a frustum part 7: Vertical groove 8 of the truncated cone part 8: Trapezoidal thin plate 9 ... Inner end surface 10 of the trapezoidal thin plate ... Outer end surface 11 of the trapezoidal thin plate ... Loosening stop nut 12 ... Conical hole 13 ... upper member 14 ... bolt hole 15 in upper member ... lower member

Claims

In the structure for preventing the loosening of the nut to be tightened into the bolt, a truncated cone part (5) is provided on the upper part of the tightening nut (3), and four to six radial slits (7) in the radial direction of the truncated cone part are provided. The trapezoidal thin plate (8) is press-fitted, and the locking nut (11) is overlapped and screwed in after the tightening nut is screwed in, so that the trapezoidal thin plate is loosened by the inner peripheral inclined surface of the conical hole (12) of the locking nut. A structure for preventing the nut from loosening, which is pushed toward the bolt and prevents the rotation of the tightening nut by the inner end face (9) of the trapezoidal thin plate biting into the top of the male screw (2) of the bolt.