JPH0635637U - Lock nut - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a lock nut that can increase the force for preventing the screw from loosening while maintaining an appropriate ring thickness that engages the thread of the bolt to prevent the screw from loosening. Plan. [Structure] The locking nut of the present invention comprises a nut body 1,
It is composed of two or more elastic rings 2 and 3 fixedly attached to the main body. This ring 2, 3
An engagement piece a that projects radially inward is formed on the inner peripheral surface of the. A spacer 4 is arranged between the rings 2 and 3, and a space is formed between the rings 2 and 3. The engagement piece a of each of the rings 2 and 3 has a thread 51, 5 of the bolt 5.
2 to prevent loosening of screws.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a lock nut.

[0002]

[Prior art]

 Conventionally, as an anti-loosening nut in which an elastic ring is attached to the nut body to prevent the nut from loosening, Japanese Utility Model Publication No. 46-8496, Japanese Utility Model Publication No. 59-37517, and Japanese Patent Application Laid-Open No. 56-160417, The ones described in Japanese Patent Laid-Open No. 56-39315 are known. The basic technical idea of these locking nuts is that an engaging piece that projects radially inward is formed on the inner peripheral surface of this elastic ring, and this engaging piece is formed on the thread of the bolt that engages with the nut. Engage. Due to this engagement, the engagement piece is deformed, and the spring action produces a stress in the substantially axial direction, and this force generates a friction torque that prevents free rotation, thereby preventing the screw from loosening. . Therefore, in order to increase the force for preventing the loosening of the screw, the elastic force of the engaging piece may be increased, and specifically, the thickness of the ring including the engaging piece may be increased. However, since the thread intervals of the bolts are limited, if the thickness of the engaging pieces is too large, it will be difficult for the engaging pieces to enter between the threads of the bolts, or the engagement with the thread Becomes too shallow, and on the contrary, the prevention of screw loosening becomes uncertain.

[0003]

[Problems to be solved by the device]

 Therefore, the present invention provides a lock nut that can increase the force for preventing the loosening of the screw while keeping the ring thickness moderate.

[0004]

[Means for Solving the Problems]

 Therefore, the present invention comprises a nut main body 1 and elastic rings 2 and 3 fixedly attached to the main body, and a member protruding radially inward from the inner peripheral surface of the elastic rings 2 and 3. A coupling piece a is formed, and this locking piece a improves the lock nut that prevents the nut from loosening by engaging with the thread of the bolt 5 that is screwed with the nut. Two or more pieces are attached to the nut body 1, and these elastic rings 2 and 3 are arranged at appropriate intervals in the axial direction of the nut body. The above-mentioned problems are solved by providing a loosening prevention nut.

[0005]

[Action]

 When the bolt 5 is screwed into the nut body 1, the thread of the bolt 5 enters through the gap between the rings 2 and 3 and engages with the engagement pieces a and a. By this engagement, the engaging pieces a of the rings 2 and 3 are deformed obliquely upward, and each stress is applied obliquely downward to the screw thread of the bolt 5 to prevent the free rotation. Torque is generated, which prevents the screws from loosening. Therefore, both rings 2 and 3 can be smoothly engaged with the male thread of the bolt as in the case where one ring is used, and even if the thickness of one ring is not increased, the looseness of the screw can be prevented with a large force Can be prevented.

[0006]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. 1 is a schematic view of a cross section of a lock nut according to an embodiment of the present invention, FIG. 2 is a schematic view of a cross section of the nut in use, and FIG. 3A is a plan view of the nut. , (B) is a plan view of the ring of the nut.

The lock nut comprises a nut body 1, two elastic rings 2 and 3 fixedly attached to the body, and a spacer 4 arranged between the rings. First, the nut body 1 will be described. A single threaded female thread 11 is formed in the central portion of the nut body 1, and the lower surface shown in the drawing serves as a seat surface 12. A caulking portion 13 is formed over the entire circumference on the upper surface opposite to the seat surface 12.

Next, the two rings 2 and 3 are made of the same material and have the same shape, and the ring 2 will be described below with reference to FIG. The ring 2 has a thin plate shape made of a spring material, and two engaging pieces a 1, a 2 projecting radially inward from the inner peripheral surface of the ring are provided with gap portions b 1, b 2 therebetween. There is. The lengths of the engagement pieces a, a and the gap portions b, b can be changed as appropriate, but in this embodiment, the engagement pieces a and the gap portions b are alternately formed every 90 degrees. The length between the facing engagement pieces a and a is slightly smaller than the inner diameter of the female screw 11, and the length between the facing gap portions b and b is smaller than the root diameter of the female screw 11. It is set.

Next, as shown in FIG. 1, the spacer 4 is composed of a ring body having a rectangular cross section, the outer diameter of which is substantially equal to the outer diameter of the ring 2, and the inner diameter of which is the gap b of the ring 2. , B is set to be slightly shorter than the distance between them. The thickness of the spacer 4 (that is, the vertical length of the spacer 4 in FIG. 1) is set to be substantially equal to one pitch of the female screw.

As shown in FIG. 1, these two rings 2 and 3 are attached to the nut body 1 with a spacer 4 interposed therebetween. This mounting is performed with the caulked portion 13 of the nut body 1 extended upward, and by bending the caulked portion 13 inward (in the direction of the arrow in FIG. 1), the rings 2, 3 and the spacer 4 are attached to the nuts. It is fixed to the main body 1. Both rings 2 and 3 are arranged so as to completely overlap each other in a plan view. That is, in other words, both rings 2 and 3 are arranged at the same position in the circumferential direction. Therefore, in the plan view shown in FIG. 3A, the ring 3 is completely hidden under the ring 2 and is not shown. Further, since the thickness of the spacer 4 (that is, the length of the spacer 4 in the upper and lower directions in FIG. 1) is set to be substantially equal to one pitch of the female screw, the axial distance between the rings 2 and 3 is It is approximately equal to one pitch of the screw.

Next, the usage state of the lock nut will be described with reference to FIG. 2. The lock nut is screwed onto the bolt 5 by a conventional method to tighten an object to be tightened (not shown). wear. The thread of the bolt 5 enters through the gap between the rings 2 and 3 and engages with the engaging pieces a and a. By this engagement, the engaging pieces a of the rings 2 and 3 are deformed obliquely upward, and the stress thereof is applied obliquely downward to the thread of the bolt 5. Here, as described above, both rings 2 and 3 are arranged at the same position in the circumferential direction, and are arranged at an interval of one pitch of the female screw in the axial direction. The rings 2 and 3 engage with the screw threads 51 and 52, which are different from each other, in exactly the same relationship with the male thread of the bolt screwed to the nut. Therefore, both rings 2 and 3 are smoothly engaged with the male thread of the bolt, as with the case of using one ring, and the looseness is prevented with double the force when using one ring. To do.

The present invention is not limited to the above-mentioned embodiment, and for example, both rings 2 and 3 can be arranged by displacing them in the circumferential direction, and the interval in the axial direction is also appropriate. Can be changed to the implementation. However, when both rings 2 and 3 are displaced by 90 degrees in the circumferential direction, the two rings are placed in a substantially similar relationship by, for example, placing an interval of 5/4 pitch of the female thread in the axial direction. It is preferable to engage the male thread. Further, the shapes of the rings 2 and 3 can be appropriately changed. For example, as shown in FIG. 4, the engaging piece a extends over three quarters and the gap portion b extends over one quarter. Alternatively, the engaging pieces a and the gap portions b may be formed in three or more places, respectively. Further, two or more rings having different shapes may be provided on the same nut body. Further, the engaging piece a of the embodiment is arranged in a plane perpendicular to the axial direction in the non-engaged state, but it may be formed to have an angle with respect to the plane. Further, in the embodiment, the spacer 4 and both the rings 2 and 3 are formed as separate bodies, but they may be formed integrally. Further, means for facilitating the positioning of the spacer 4 and the rings 2 and 3 may be provided, such as providing a protrusion on the nut body and providing notches corresponding to the spacer 4 and the rings 2 and 3.

[0013]

[Effect of device]

 As described above, the present invention can provide a locking nut that can increase the force for preventing the screw from loosening while keeping the ring thickness moderate.

[Brief description of drawings]

FIG. 1 is a schematic view of a cross section of a lock nut according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of the nut in a used state.

FIG. 3A is a plan view of the nut, and FIG. 3B is a plan view of a ring of the nut.

FIG. 4 is a plan view of a ring according to another embodiment.

[Explanation of symbols]

 1 nut body 2 ring 3 ring 4 spacer 5 bolt a engaging piece b gap part

Claims (1)

[Scope of utility model registration request] 1. A nut main body and an elastic ring fixedly attached to the main body, and an engaging piece projecting radially inward is formed on an inner peripheral surface of the elastic ring. In a lock nut for preventing the nut from loosening by engaging a thread of a bolt whose one piece is screwed with the nut, two or more elastic rings are attached to the nut body, and these elastic rings are A loosening prevention nut characterized in that it is arranged at an appropriate interval in the axial direction of the nut body.