JP2014219093A - Fastening member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fastening member capable of being stabilized and capable of improving reliability in locking against looseness by adding a preferable fastening frictional force by a spring to a member to be fastened.SOLUTION: This invention relates to a fastening member in which a coil spring is formed at a first fastening member (nut) and a ball screw is formed at a second fastening member (bolt). A tension coil spring and a compression coil spring are integrally formed in the first fastening member, an inner diameter of the coil spring is formed to have a smaller diameter than a root diameter of a thread part of the second fastening member and lastly the end part of the coil spring is locked by crossing the shank part of the second fastening member inside in the fastening direction, and then a stronger frictional force is applied to it and a repelling force of the compression coil spring is realized.

Description

  The present invention relates to a fastening member that fastens and fixes a member by utilizing a spiral portion and a repulsive force of a coil spring, and more particularly to a fastening member having a loosening prevention function.

  Nuts and bolts have been widely used in various fields as fastening members used for fastening and fixing component members. These nuts and bolts are used to fasten and fix parts and members, but there is a problem that the nuts and bolts loosen when vibrations repeatedly act on these fastening parts. It is often used to use a flat washer or a spring washer.

  However, even if a flat washer or a spring washer is used, the problem that nuts and bolts are loosened depending on the application has not been solved. For this reason, many means and methods have been proposed for preventing loosening of nuts and bolts, and some of them have been put to practical use. As an example, a locking nut disclosed in Japanese Patent No. 4494849 (Patent Document 1) includes a lower nut and an upper nut in which screw holes are formed in a penetrating manner, and the lower nut has a shaft around the screw hole. A convex portion having a tapered outer peripheral surface whose diameter decreases in accordance with the outer side in the direction is formed, and the outer peripheral surface of the convex portion is eccentric by a minute amount with respect to the screw hole, and the convex portion of the lower nut is fitted to the upper nut. A concavity is formed, and the inner peripheral surface of the concavity is concentric with the screw hole. In this way, by decentering the convex part and the concave part, when the nuts are tightened, the nuts are displaced in the radial direction with respect to the screw hole axis, respectively, and the radial stress acts on the screw shaft. It is trying to stop loosening by the wedge effect.

  In addition, the locking nut disclosed in Japanese Patent Application Laid-Open No. 2005-140272 (Patent Document 2) is formed by notching a groove portion from both directions of the outer peripheral surface to the female screw shaft center of the nut 3 from the outer peripheral surface of the nut. Then, when the female screw of the nut 3 is screwed into the male screw of the bolt fixed to the object to be fastened, and a predetermined tightening is performed, a loosening prevention member made of an elastic material is inserted into the groove portion of the nut, thereby The surface and the valley slope of the male screw are pressed against each other in a pressurized state to prevent loosening.

  The loosening prevention nut exemplified in Patent Document 1 uses a so-called double nut to prevent loosening, but the screw directions of the two nuts and bolts are the same, and the double nut rotates due to repeated action of vibration. Therefore, the problem of loosening is still not solved. Also, in the locking nut illustrated in Patent Document 2, the nut is pressed against the male thread circumferential surface of the bolt in a pressurized state, and since there is a slack due to repeated vibration, there is a reliability. There was a poor problem.

  In order to solve this problem, it has also been proposed to prevent loosening by constituting two nuts as reverse screws in the loosening prevention nut adopting a double nut system. For example, Japanese Patent Laying-Open No. 2003-301829 (Patent Document 3) is provided with a reverse screw shaft in which a screw is formed in a direction opposite to the inner peripheral surface screw of the nut on the bolt head side on the outer peripheral surface of the nut. The lock nut is screwed onto the reverse screw shaft to prevent the nut from loosening. With such a configuration, when vibration or the like is applied and the nut tries to loosen, the lock nut acts in the tightening direction and can be prevented from loosening.

Japanese Patent No. 4495849 JP 2005-140272 A JP 2003-301829 A

  However, in the double nut method disclosed in Patent Document 3, even if the locking nut is provided with a reverse screw shaft, two nuts rotate unless the tightening force is strictly controlled to a predetermined value. There is a problem that causes slack. The reason for this will be described with reference to FIG. The bolt I is inserted into a through-hole provided in the fastened body F, and a nut J is screwed to the bolt I and is fastened and fixed. At this time, when the nut J is tightened with a large force, the fastened body F is depressed by the nut J even though the surface of the fastened body F is flat in a normal state. As shown in FIG. 5, this depression causes a peculiar stress in which the inner side near the bolt I and the outer side near the outer periphery of the nut J are greatly recessed and a raised portion H is generated at the center. For this reason, the area of the contact surface between the seating surface of the nut J and the fastened body F is reduced, and as a result, the frictional force on the installation surface is reduced and it becomes easy to loosen. Therefore, unless the tightening force is strictly managed, the characteristics of the locking nut provided with the reverse screw shaft cannot be exhibited. Such a loosening phenomenon is also the same in the loosening prevention nuts disclosed in the above-mentioned documents 1 and 3, and a serious problem in which a loosening occurs depending on a specific tightening force control even though it has a loosening prevention effect. was there.

  The problem to be solved by the present invention is to improve the reliability of the loosening prevention stably by applying the repulsive force of the coil spring and the tightening friction force of the helical portion as the tightening friction force between the fastening member and the fastened member. It is providing the fastening member which can do.

  Accordingly, a fastening member according to the present invention includes a first fastening member using a coil spring and a second fastening member formed with a plurality of ball screws, and the first and second fastening members are screwed to each other. When the fastening body is fastened with a predetermined pressing force, a pressing force substantially equivalent to the pressing force is applied to the coil spring flank surface and the second fastening member flank surface of the first fastening member, thereby providing a strong loosening prevention effect. I can play.

  The first fastening member is constituted by a nut in which a coil spring is formed and a bolt in which a plurality of ball screws are formed in the second fastening member shaft portion, and the nut is screwed onto the bolt. It is concluded.

  Further, the nut as the first fastening member has a coil spring tightening portion that rotates around the axis, and a plurality of tension coil springs are formed concentrically with the fastening portion, and the compression coil spring gradually moves toward the seat surface from the middle of the nut. This is a fastening member having an enlarged diameter and an integrated shape.

  The inside diameter of the first fastening member tension coil spring portion described above is characterized in that it is smaller than the diameter of the second fastening member ball screw valley, and the body to be fastened can be fastened integrally with the tension coil spring. It is a feature. The fastened body is fastened with the fastening member, and finally, the end of the coil spring is crossed inward in the fastening direction with the second fastening member shaft portion, whereby a strong frictional force can be obtained.

  The bolt as the second fastening member has a head portion for rotating around the axis, and a ball screw is formed on the screw shaft concentrically with the head portion from the head portion base portion integrally with the head portion. The fastening member is characterized in that a tension coil spring is fitted to the fastening member.

  The second fastening member is a fastening member in which a plurality of ball screws are formed in a screw hole formed in the fastened body, and the second fastened member is screwed and fastened to the fastened body.

  According to the present invention, the first fastening member coil spring is configured as a nut portion, and the second fastening member shaft portion is configured as a bolt formed with a plurality of ball screws. By screwing and fastening the first fastening member and the second fastening member, vibration and impact can be absorbed and the loosening prevention effect can be prevented by utilizing the repulsive force of the coil spring.

  The first fastening member has a tension coil spring portion and a compression coil spring portion integrally formed, and the tension coil spring portion is formed with a smaller diameter than the ball screw valley diameter portion of the second fastening member shaft portion. By tightening, a strong frictional force can be obtained, and a great effect on loosening can be achieved.

  Further, vibration and impact are absorbed by the compression coil spring portion of the first fastening member, so that initial looseness and aging deterioration due to depressions and scratches can be prevented on the fastened body surface, and a stable loosening prevention effect can be expected.

  The fastening member using the coil spring can select a tightening torque that allows the body to be fastened to be made of various materials, and can be used as a loosening fastening member in various places.

  Furthermore, the first and second fastening members can be easily manufactured by a known general processing method with a simple configuration.

It is an elevation view which shows the integrated coil spring of the tension coil spring and compression coil spring of the 1st fastening member in connection with this invention. It is a side view of the 2nd fastening member (bolt) in connection with this invention. It is sectional drawing which fastened the to-be-fastened body by the 1st fastening member and 2nd fastening member in connection with this invention. It is sectional drawing which fastened the to-be-fastened body by the 2nd fastening member in connection with this invention. It is a raised sectional view of the to-be-fastened body surface which occurs at the time of commercial bolt and nut fastening.

  A fastening member that uses a coil spring to reinforce its repulsive force and tightening frictional force and fastens various materials. The first fastening member is formed integrally with a tension coil spring and a compression coil spring. The part is applied to the ball screw flank part of the bolt part of the second fastening member, and the compression coil spring part is pressed against the face to be fastened to absorb the vibration and impact.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is an elevational view showing an integrated coil spring of a tension coil spring and a compression coil spring of a first fastening member according to the present invention, and an inner diameter of the first fastening member tension coil spring portion is a second fastening member. It is characterized in that it is formed smaller than the diameter of the shaft ball screw valley, and a strong frictional force is generated at the time of fastening. Further, in the compression coil spring portion, a loosening-fastening fastening member that can be used in various fields by changing the fastening torque in various ways by various fastening bodies by generating a repulsive force peculiar to the coil spring at the time of fastening.

FIG. 2 is a side view of a second fastening member (bolt) according to the present invention.
As the greatest feature of the present invention, by making the bolt screw valley diameter larger than the first fastening member tension coil spring inner diameter, the valley diameter is compressed and tightened at the time of tightening. Further, the contact portion of the first fastening member tension coil spring is forcibly expanded by the flank portion of the ball screw, and the contact portion can be brought into close contact pressure.

  FIG. 3 is a cross-sectional view in which a fastened body is fastened by a first fastening member and a second fastening member according to the present invention. A ball screw is formed on the fastening member shaft portion formed in the second fastening member bolt, and the threaded valley diameter is formed larger than the inner diameter of the tension coil spring, and when fitted, the tension coil spring expands outward. While tightening, screw into the ball screw and tighten. The tension coil spring is in close contact with the flank portion of the ball screw and is pressed in the direction in which the spring is expanded to increase the frictional force. Therefore, there is a strong force between the ball screw shaft and the tension coil spring. It can be brought into close pressure contact, and after tightening, the end of the coil spring can be locked by crossing the second fastening member shaft portion inward in the tightening direction, thereby achieving a suitable loosening prevention effect.

  FIG. 4 is a cross-sectional view in which a fastened body is fastened by a second fastening member according to the present invention. A flank portion of the coil spring is formed by forming a ball screw on the fastening member shaft portion formed in the second fastening member bolt, fitting a tension coil spring to the screw portion, screwing and tightening to the ball screw of the fastening member. The second fastening member can be brought into close contact with the ball screw flank, and unlike the existing screw thread, the coil spring is free. It can be generated to exert the effect of preventing loosening.

  FIG. 5 is a cross-sectional view of a general commercial bolt and nut when fastened. By increasing the tightening torque of the nut of J, the fastened body portion of F is raised, and the pressure contact surface is reduced to cause looseness.

  Although the present invention has been specifically described above based on the embodiments, it is needless to say that the present invention is not limited to the above-described embodiments and can be variously modified without departing from the gist thereof.

  INDUSTRIAL APPLICABILITY The present invention can be summarized for fastening a member to be fastened used for a machine tool, an electric machine tool, a vehicle, a construction, a building, a railway, or the like.

A Tension coil spring part F Fastened member B Compression coil spring part G Bolt screw part C Coil spring seat surface H Seat surface raised part D Tension coil spring tightening part I Commercial bolt E Bolt J Commercial nut

Claims (6)

  A fastened member for fastening a fastened body, the fastening member comprising a first fastening member using a plurality of coil springs and a second fastening member formed with a plurality of ball screws, When the first and second fastening members are screwed together and the fastening body is fastened with a predetermined pressing force, a pressing force substantially equivalent to the pressing force is applied to the coil spring flank surface of the first fastening member and the second fastening member. A fastening member characterized by being applied to a fastening member flank surface.   The first fastening member is configured as a nut formed with a plurality of coil springs, and the second fastening member is configured as a bolt formed with a plurality of ball screws. The nut is screwed into the bolt. The fastening member according to claim 1, which fits together.   The nut as the first fastening member is formed of a coil spring tightening portion that rotates around the axis of the second fastening member and a plurality of tension coil springs that are concentric with the tightening portion, and a plurality of compression coils from the middle. The fastening member according to claim 2, wherein the spring is gradually expanded in diameter toward the seating surface and is formed into an integral shape.   The inside diameter of the first fastening member tension coil spring portion is smaller than the diameter of the second fastening member ball screw valley, and the end of the coil spring is clamped to the second fastening member shaft after tightening. The coil spring fastening member according to claim 3, wherein the coil spring fastening member is crossed inward in a portion fastening direction.   The bolt as the second fastening member has a head portion for rotating around an axis, and a ball screw formed on the screw shaft concentrically with the head portion from the base portion of the head portion integrally with the head portion. The fastening member according to claim 1, wherein a tension coil spring is fitted to the screw.   The fastening member according to claim 1, wherein the second fastening member has a plurality of ball screws formed in a screw hole formed in the fastened body, and is screwed into the fastened body to be fastened.

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