JP3960461B2 - Locking nut - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a locking nut.
[0002]
[Prior art]
Conventionally, various locking nuts have been devised.
[0003]
[Problems to be solved by the invention]
However, there is no low cost, high productivity, and a stable anti-loosening action even when used several times.
Accordingly, an object of the present invention is to provide a method of manufacturing a locking nut that is low in cost, high in productivity, and capable of exhibiting a stable locking action even when used several times.
[0004]
[Means for Solving the Problems]
The nut manufactured according to the present invention has a tool mounting portion and a protruding portion protruding in the axial direction from the tool mounting portion, and a bolt hole is provided over the tool mounting portion and the protruding portion. In the nut, a plurality of vertical grooves are formed in the circumferential direction on the outer peripheral side of the projecting portion, and at least one of the blocks between the vertical grooves is pressed and deformed inward in the radial direction. .
[0005]
In such a locking nut, since a longitudinal groove is formed between a block to be pressed and a block adjacent to the block, only a required block can be deformed by a press or the like while suppressing deformation of the adjacent block. Moreover, the deformation can be carried out without difficulty, and the productivity can be improved and the cost can be reduced.
In addition, before fastening to the bolt, the bolt hole is reduced in diameter in the inner peripheral portion of the block that has been pressed and deformed, and when the bolt is fastened, the block is expanded outward in the radial direction by the bolt. However, at this time, since the longitudinal groove forming portion exerts a resilient action and elastically deforms, when the nut is removed from the bolt, it returns to the original reduced diameter deformation state by the elastic force, Also exerts a large and stable locking action.
[0006]
In addition, in the case where a plurality of blocks deformed by pressing are uniformly arranged over the entire circumference at a constant interval in the circumferential direction, the blocks act upon these blocks when they are deformed by pressing from the outer periphery during manufacture. The pressing force is canceled out, the support of the nut at the time of deformation can be simplified, and the plurality of blocks can be deformed substantially uniformly.
Furthermore, when the product is used, a load acts between the deformed block inner surface and the bolt outer surface when screwed into the bolt, but the load acts uniformly in the circumferential direction. And the nut shaft center are almost eliminated, the workability of fastening to the bolt is improved, and a large compressive force can be prevented from acting only on a part in the circumferential direction.
Although the number of such a plurality of deformation blocks is preferably three, two may be provided so as to be positioned in the diameter direction, or four or more may be provided.
[0007]
Moreover, it is preferable that the outer diameter of the block deformed by pressing is larger than the outer diameter of the block not deformed by pressing at least before the deformation. According to such a configuration, the block to be pressed and deformed protrudes radially outward as compared with the other blocks, and therefore the block to be deformed can be easily pressed and deformed.
[0008]
Further, in the case where the protruding portion has a truncated cone shape whose outer diameter is reduced in the axial direction, the press body having a truncated cone-shaped concave portion into which the protruding portion fits easily and quickly. The required blocks can be deformed to further improve productivity and reduce costs. Furthermore, the amount of deformation can be easily adjusted by adjusting the compression stroke of the press body. Since the portion of the protruding tip side gradually becomes thinner, the tip side is deformed relatively easily.
[0009]
As a manufacturing method of the above described locking nut of the present invention, the following is preferable.
First, it has a tool mounting part and a projecting part projecting in the shape of a truncated cone tapered outward from the tool mounting part in the axial direction, and on the outer peripheral side of the projecting part in the circumferential direction An intermediate product is formed by forming a plurality of longitudinal grooves and a bolt hole extending between the tool mounting portion and the projecting portion, and from above the projecting portion of the intermediate product, between the longitudinal grooves By pressing a press body in contact with at least one outer surface of each of the blocks along the axial direction against the intermediate product, the partial block is deformed in a radial direction.
[0010]
According to such a method, the wedge action (taper action) of the contact portion between the projecting portion and the press body can apply a large pressing force to the required block in the direction of diameter reduction, thereby ensuring reliable deformation processing. In addition, by synchronizing the transport of the intermediate product and the reciprocating motion of the press body, it is possible to manufacture a locking nut of a certain quality with extremely high productivity.
Further, since the contact portion between the press body and the projecting portion is tapered, the deformation amount of the projecting portion also linearly changes depending on the stroke amount of the press body, so that a minute amount of deformation can be adjusted.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
1 to 4 show a locking nut 1 according to an embodiment of the present invention. The nut 1 has a tool mounting portion 2 having a hexagonal nut shape and a projecting portion 3 protruding in the axial direction from one axial end side of the tool mounting portion 2. The tool mounting portion 2 and the projecting portion 3 are desirably integrally formed by cold forging, but hot forging or other forming methods can also be used.
[0012]
The protruding portion 3 has a truncated cone shape whose outer diameter is reduced in the axial direction outward, and a plurality of vertical grooves 6 are formed in the circumferential direction on the outer peripheral side of the protruding portion 3. Yes. The vertical groove 6 is a long concave groove formed over the entire axial length of the projecting portion 3 and can be simultaneously formed during the cold forging described above.
Further, a bolt hole 7 extending between the tool mounting portion 2 and the protruding portion 3 is formed.
[0013]
In the illustrated embodiment, six longitudinal grooves 6 are provided as shown in FIG. Further, if the two longitudinal grooves 6 are paired, a total of 3 longitudinal groove pairs are formed, and the circumferential width of the block 4 between the pair of longitudinal grooves 6 is different between the adjacent longitudinal grooves 6 of different pairs. 5 is about half the circumferential width.
The block 4 between the pair of longitudinal grooves 6 is pressed and deformed by a slight amount radially inward after the bolt hole 7 is formed, and thus the bolt hole 7 is distorted in the inner surface portion of the block 4. However, it is designed to prevent loosening when attached to a bolt.
[0014]
That is, in the illustrated embodiment, there are three blocks 4 that have been pressed and deformed, and these three blocks 4 are evenly arranged over the entire circumference with a constant interval in the circumferential direction.
The outer diameter of the block 4 that is deformed by pressing is larger than the outer diameter of the block 5 that is not deformed by pressing.
[0015]
A method for manufacturing the above-described locking nut 1 will be described below.
First, by cold forging, the outer shape of the hexagonal nut-shaped tool mounting portion 2 and the outer shape of the tapered truncated cone-shaped protruding portion 3 protruding outward from the tool mounting portion 2 in the axial direction. Form. At this time, the longitudinal groove 6 is formed in the projecting portion 3, and the outer diameter of the deformation target block 4 is forged so as to be larger than the outer diameter of the non-deformable block 5. After such forging, the bolt holes 7 are formed by cutting, and an intermediate product 9 before deformation (before caulking) is obtained. The female thread valley diameter P of the bolt hole 7 in the intermediate manufactured body 9 is the same over the entire axial length. In addition, you may form the bolt hole 7 simultaneously at the time of the said forging.
[0016]
The intermediate product 9 is conveyed to a press machine by a conveyor or the like, and the deformation target block 4 is pressed and deformed radially inward by the press machine. This press machine includes a press body 10 (die) having a recess 11 into which the protruding portion 3 of the nut 1 is fitted, and by moving the press body 10 up and down, The deformation target block 4 of the projecting portion 3 is reduced in diameter by a required amount. After this deformation, the female thread valley diameter S at the projecting portion 3 side end of the bolt hole 7 on the inner surface side of the deformation block 4 is slightly reduced from the diameter P before deformation as shown in FIG. If the deformation amount inward in the radial direction of the block 4 is ds,
P = S + 2ds
The relationship is almost true.
[0017]
The inner peripheral surface of the concave portion 11 is formed in a truncated cone shape, and is configured so as to be able to come into surface contact with the outer surface of the deformation target block 4, and the press body 10 with respect to the intermediate manufacturing body 9 only in a required stroke along the axial direction. By pressing, the block 4 is strongly deformed by a taper action while being in surface contact with the outer surface of the deformation target block 4.
[0018]
According to this manufacturing method, by adjusting the stroke amount of the press body 10, the required deformation amount of the block 4 can be adjusted easily and accurately, and quality and productivity can be improved.
[0019]
The present invention is not limited to the embodiment shown in the drawings, and can be appropriately changed in design.
For example, in the illustrated embodiment, the number of deformation target blocks 4 is three, but may be one, two, or four or more.
[0020]
Further, the outer diameter of the deformation target block 4 is larger than the outer diameter of the non-deformation block 5, but it may be the same diameter, and the outer diameter of the deformation target block 4 is larger than the outer diameter of the non-deformation block 5. It can also be made smaller. As a deformation method by the press body 10 in this case, the shape of the press body 10 is designed so that the press body 10 contacts only the outer surface of the small-diameter deformation target block 4 (for example, on the inner periphery of the recess 11 of the press body 10). It is conceivable that a ridge is provided).
[0021]
Further, the shape of the tool mounting portion 2 is not limited to the hexagonal nut shape, and may be any shape that matches any tool present and present in the future.
[0022]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the locking nut which exhibits the stable locking | rock prevention effect | action also at the time of multiple use of attachment / detachment is obtained at low cost, and can also improve productivity.
[Brief description of the drawings]
FIG. 1 is a perspective view of a locking nut according to an embodiment of the present invention.
FIG. 2 is a plan view of the locking nut.
FIG. 3 is a longitudinal sectional view showing a manufacturing process of the locking nut.
4 is a cross-sectional view taken along line AA in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Locking nut 2 Tool mounting part 3 Projection part 4 Deformation target block 5 Non-deformation block 6 Vertical groove 7 Bolt hole 9 Intermediate manufacturing body 10 Press body

Claims (1)

It has a tool mounting part (2) and a projecting part (3) projecting in the axial direction from the tool mounting part (2), and over these tool mounting part (2) and projecting part (3) In the nut provided with the bolt hole (7),
A plurality of vertical grooves (6) are formed in the circumferential direction on the outer peripheral side of the protruding portion (3), and the vertical grooves (6) are formed over the entire axial length of the protruding portion (3). And at least one block (4) of the blocks (4, 5) between the longitudinal grooves (6) is pressed and deformed radially inward, thereby forming a bolt. The bolt hole is reduced in diameter at the inner peripheral portion of the block (4) so that the block (4) pressed and deformed by the bolt is expanded radially outward when the bolt is fastened. The groove (6) is formed between a block (4) to be pressed and deformed and a block (5) adjacent to the block (4), and a locking nut .

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