JP2005240964A - Anti-loosening screw - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an anti-loosening screw maintaining an anti-loosening effect for a long period. <P>SOLUTION: A screw portion is constituted of a head portion 2 and a leg portion 4 in which a thread 5 is formed at an outer periphery integrally with the head portion. In this anti-loosening screw, a groove 10 deeper than a thread valley portion 6 is formed along an axis in an axial direction of the leg portion 4, and a locking member 20 which consists of a metallic line 21 and a resin material 22 accommodating the line therein is fitted and inserted in the groove 10, therefore, the resin material is deformed having elasticity along a female screw, and the metallic line is pressed against the elastic force of the resin material in the groove by the female screw to cause large locking effect in relation with the female screw. Besides, the metallic line is fitted in, therefore, pressure force is equally applied to the resin material in the groove, and restoring force is maintained, and the anti-loosening effect is not extraordinarily degraded in repeated use of the screw. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  According to the present invention, when a locking member is inserted into a groove formed along an axis of a leg portion of a screw component and screwed into a female screw of a workpiece such as a nut or a component and tightened, the screw is not easily loosened. The present invention relates to a loosening set screw.

  Generally, a groove having a predetermined depth is formed along the axis of the leg portion on which the thread is formed, and an elastic body such as rubber or a resin material having an elastic force such as polyethylene resin or polyamide resin is used as the main material in the groove. Many screw parts into which a locking member is inserted are used as locking screws. The screws having such a configuration have a relatively high locking effect and are widely used in spectacle frames and places where vibrations are relatively generated. However, when this screw is used repeatedly, the restoration property of the locking member is good at first, but if it is used repeatedly, the surface will be scraped off, fatigue or plastic deformation will reduce the restoration property, and The service life is short due to deterioration of the resin material. Further, since the locking member is only fitted into the groove and sandwiched between both side walls of the groove and supported by the elastic force of the locking member, a lot of dropping occurs during use. There were problems such as the occurrence of many defective products.

In order to solve this problem and to obtain a loosening prevention effect efficiently, there are also those shown in FIGS. This was invented mainly to eliminate the drawback of preventing the synthetic resin elastic body 122 as a locking member from falling off the axial groove 110 formed in the leg 104. This is provided with two vertical grooves at positions substantially intersecting with the groove around the screw body 104, the vertical grooves having the same opening 113, and a chevron 114 at the center of the bottom 112, and opposing side walls. 111 and 111 are oblique grooves inclined inward toward the opening 113. Then, the bottom surface is provided with a single groove 124 smaller than the chevron 114 of the groove 110, and a synthetic resin elastic body 122 having elasticity and resilience is fitted to the protrusion 114 of the groove 110 of the screw body 104. To be fixed. Thereby, since the synthetic resin elastic body 122 spreads and fits on both sides of the groove 110, it can be completely fixed in the groove (for example, see Patent Document 1).
JP 47-39854 A

  However, when such a synthetic resin elastic body is fitted in the groove of the leg portion, the synthetic resin elastic body is less likely to fall out of the groove, but the loosening prevention action that is the original purpose of the elastic body is reduced. Is not much different from the previous locking screw, that is, in the screw using the locking member made of this synthetic resin elastic body, the restoring force of the locking member after repeated use is reduced, and the function is sufficient. In addition, the life due to deterioration of the locking member is still short. For this reason, there are problems such as periodic inspections and additional tightening, and the need to frequently replace the locking screws.

  An object of the present invention is to solve such problems and to obtain a locking screw that maintains a long and stable locking operation.

  An object of the present invention is a screw component including a head portion 2 serving as a driving portion and a leg portion 4 formed integrally with the head portion 2 and having a screw thread 5 formed on the outer periphery thereof, and is screwed along the axis in the axial direction of the leg portion 4. This is achieved by forming a groove 10 deeper than the valley 6 and providing a locking screw in which a locking member 20 comprising a metal wire 21 and a resin material 22 containing the metal wire 21 is inserted.

  Further, in this configuration, when the locking member is fitted in the groove 10, the surface on the side of the thread 5 is positioned outside the effective diameter of the thread, so that it is sufficient when engaged with the female thread. The anti-loosening action is demonstrated. Furthermore, since the metal wire included in the resin material is configured so that the position when the metal wire is inserted into the groove 10 is at least outside the diameter of the thread valley portion 6, The locking action is ensured. In addition, in the above configuration, when the locking member is inserted into the groove 10 of the leg 4, the distance from the head 2 is short on the thread surface side, and the distance from the head 2 is the center of the leg 4. Since the structure has the inclined surface 23 inclined so as to be long, the locking member is prevented from falling off when screwed with the female screw.

  According to the present invention, the locking member in which the metal wire is inserted into the resin material is fitted into the groove formed along the axis on the surface side of the leg portion, and this is screwed into the female screw of the workpiece. Since it is a locking screw, the resin material is elastically deformed along the female screw and the metal wire is pressed into the groove by the female screw against the elastic force of the resin material. A large anti-loosening action occurs. In addition, because the metal wire is inserted, the resin material in the groove is equally pressed, so that the restoring force is maintained, and the locking function is extremely reduced even when the locking screw is used repeatedly. There is no. Furthermore, since the locking member is fitted and inserted into both side walls of the groove with a resilient force, it is possible to reduce the falling off of the screw groove. In addition, when the locking member is inserted into the groove of the leg portion, the locking member has a slope inclined from the thread surface side to the center side of the leg portion. There is a peculiar effect that the drop-off from the screw is reduced and the screwing with the female screw becomes smooth.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 3, reference numeral 1 denotes a locking screw according to the present invention, and in the figure, reference numeral 2 denotes an engagement as a drive unit with which a driver bit (not shown) for screwing and driving the screw 1 is engaged on the center line. It is a head in which the groove 3 is formed. The head portion 2 is integrally formed with a leg portion 4 having a smaller diameter and having a thread 5 formed on the outer peripheral surface. A groove 10 having a predetermined length is cut from the tip of the leg 4 to the head side along the axis, and the groove 10 is formed deeper than the diameter of the thread valley 6. In this embodiment, the groove 10 is cut from the tip of the leg 4 to the head. However, other than this, for example, near the center of the leg 4, the head of the leg 4 or the like is necessary. Depending on the position, it may be cut at any position.

  A locking member 20 is inserted into the groove 10 so as to be pinched by the side walls 11 on both sides of the groove 10. The locking member 20 is provided with a metal wire 21 at the center, and the metal wire 21 is covered with a resin material 22 so as to enclose the metal wire 21. The resin material 22 is usually made of polyethylene resin, polyamide resin, or the like, and can be used to obtain predetermined elasticity. The loosening prevention member 20 having such a configuration is configured such that when it is fitted into the groove 10, the surface on the thread side is at least thicker than the effective diameter of the thread. The thickness of the metal wire 21 varies depending on the size of the groove 10 so that the elasticity of the resin material 22 is maintained when it is inserted. That is, the resin material 22 covering the metal wire 21 has a thickness that can exhibit sufficient elasticity.

  Further, the metal wire 21 included in the resin material 22 is configured so that the position when the metal wire 21 is inserted into the groove 10 is positioned at least outside the thread valley portion 6, thereby the locking member 20. Prevents the loosening action due to the repulsive force of the resin material 22 that covers the metal wire 21 and contacts the bottom 12 of the groove 10 when it interferes with the internal thread 31 formed on the work 30. ing. The metal wire 21 may be made of copper, stainless steel or the like.

  On the other hand, as shown in FIG. 4, in the state where the locking member 20 is inserted into the groove 10 formed in the leg portion 4 of the screw 1, the screw thread surface side has a short distance from the head 2, The center side of the leg 4 has a slope 23 that is inclined so as to increase the distance from the head 2, so that the locking member 20 is elastic to the female screw 31 when screwed with the female screw 31. It is adapted to be screwed in while deforming to prevent falling off.

  As shown in FIG. 5, when the loosening set screw 1 configured as described above is screwed into the female screw 31 formed on the workpiece 30, the tip of the leg portion of the screw 1 is first screwed into the female screw 31. Start. At this time, the loosening prevention member 20 of the leg 4 is gradually pressed into the groove 10 while the resin material 22 is deformed along the female screw 31. In this way, when the screw 1 is screwed into the female screw 31 and tightened, the locking member 20 is in a state where the resin material 22 at the bottom of the groove 10 is compressed by the metal wire 21, and the repulsive force thereof. Acts on the internal thread 31 to prevent loosening.

  Further, as shown in FIG. 6, the resin material 22 at the position of the thread surface deformed by the female screw 31 slightly extends along the female screw 31 on both sides of the groove 10 and between the screw threads 5 to prevent loosening. Is demonstrated. Further, when this is loosened, the loosening prevention member 1 exhibits a sufficient loosening prevention effect even if the metal wire 21 returns to its original position due to the elastic force of the resin member 22 and is screwed again. become.

It is a front view showing the present invention. It is a bottom view of FIG. It is an AA line expanded sectional view of FIG. It is a fragmentary sectional view which follows the BB line of FIG. It is a principal part expanded sectional view which shows the screwing state of this invention. FIG. 6 is a partial cross-sectional view of a main part along the line CC in FIG. 5. It is a front view which shows a prior art example. FIG. 8 is a bottom view of FIG. 7.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Loosening set screw 2 Head 3 Engagement groove 4 Leg part 5 Screw thread 6 Screw thread valley part 10 Groove 11 Side wall 12 Bottom 20 Loosening prevention member 21 Metal wire 22 Resin material 23 Slope 30 Workpiece 31 Female screw

Claims (4)

  A screw component comprising a head portion (2) serving as a driving portion and a leg portion (4) integrally formed therewith and having a screw thread (5) formed on the outer periphery, wherein the thread valley along the axis in the axial direction of the leg portion A groove (10) deeper than the portion (6) is formed, and a locking member (20) comprising a metal wire (21) and a resin material (22) containing the groove is inserted into the groove (10). Locking screw.   2. The locking screw according to claim 1, wherein when the locking member is fitted in the groove, the surface on the thread side is positioned at least outside the effective thread diameter. The slack according to claim 1 or 2, wherein the metal wire included in the resin material is configured such that a position when the metal wire is inserted into the groove is positioned outside at least the diameter of the thread valley portion. Set screw.   When the locking member is inserted into the groove of the leg, the inclined surface (23) is inclined so that the distance from the head is short on the thread surface side and the distance from the head is long on the center side of the leg. 4. The loosening set screw according to claim 1, 2 or 3, wherein the setscrew has a configuration having the same.

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