JP2007092925A - Bolt - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bolt allowing it easily fit and meshed with a nut, without causing the nut to be unexpectedly dropped. <P>SOLUTION: This bolt 1 has a head part 11 in one end part and a screw part 12 in the other end part, and the nut 3 is screw-fitted into the screw part 12 to tighten bodies A, B to be tightened. Next, a nut guiding part 13 has outside diameter being smaller than inside diameter of a screw part 3a of the nut 3 and is provided in a tip part of the screw part 12. One annular channel 1a or more for making leaving of the nut 3 difficult are provided in a tip part of the nut guiding part 13. Consequently, the nut 3 is inserted into the nut guiding part 13 and is guided into the tip part of the screw part 12 to fit and mesh the nut 3 in/with the bolt 1 easily and prevent the nut 3 from dropping unexpectedly. In this case, length of the nut guiding part 13 can be shortened than that of a conventional nut guiding part, and the nut 3 can be smoothly removed from the nut guiding part 13. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a bolt. In particular, the present invention relates to a bolt structure that has been treated for the loss of a nut fastened to the bolt.

  As a measure against the loss of the nut, there are generally considered a drop-off prevention structure that prevents the nut from loosening due to vibration after the bolt and the nut are fastened and falling off the nut from the bolt. As such a nut drop prevention structure, an inexpensive nut drop prevention structure has been invented so that the nut can be prevented from dropping with a simple structure (see, for example, Patent Document 1).

  In the nut drop prevention structure according to Patent Document 1, the male screw at the tip of the threaded portion of the bolt is dimensioned so that the root diameter of the male screw is larger than the inner diameter corresponding to the female screw of the nut screwed into the bolt. Yes. As a result, the male screw at the tip of the threaded part of the bolt is formed into a slightly different thread shape on the side where the meshing is tighter than the root diameter of the male thread on the base end side of the threaded part, which is a regular standard dimension corresponding to the female thread of the nut Has been. The nut once screwed into the screw base end side of the bolt is held in a state where it is prevented from coming off from the bolt unless a rotational torque of a predetermined value or more is applied artificially.

  On the other hand, there has been invented a bolt that has a structure in which a nut does not fall even when an operator removes a finger from the nut at the time of attaching or removing the nut (see, for example, Patent Document 2).

The bolt according to Patent Document 2 is used when the operator removes the finger from the nut before the first screwing when attaching the nut, or when the operator removes the screw from the nut when removing the screw. If the nut is released, the removed nut can be prevented from being caught by the screwless portion and falling off the nut.
JP 2003-42132 A JP 2004-263830 A

  When the nut is fastened to the bolt, the nut is fitted and meshed from the tip of the bolt protruding from the fastened object. For example, such a fastening operation is a manual operation, and a nut picked by a finger may be dropped inadvertently without being fitted into a bolt. It is inconvenient to drop the nut in the fastening work at a high place. Further, in the fastening operation in a dark place at hand, it is difficult to engage and engage the nut from the tip of the bolt.

  Although the nut fall prevention structure according to Patent Document 1 is effective for preventing the nut from falling after the nut is fastened to the bolt, the nut may be inadvertently dropped when the nut is fitted and meshed with the bolt. Is not considered. If the nut can be easily fitted and engaged with the bolt without inadvertently dropping the nut, the fastening operation at a high place or the fastening work in a dark place at hand becomes easy and convenient.

  FIG. 5 is a side view showing the bolt according to the first embodiment according to Patent Document 2. As shown in FIG. FIG. 5 of the present application corresponds to FIG. In FIG. 5, the bolt 5 includes a male screw portion 6 and a non-threaded portion 7 projecting from the tip of the male screw portion 6. The unthreaded portion 7 includes a distal end portion 7 a having a maximum outer diameter smaller than the inner diameter of a nut (not shown), and a recess 7 b between the distal end portion 7 a and the proximal end of the unthreaded portion 7. The recess 7b has a length larger than the thickness of the nut and has a minimum outer diameter smaller than the maximum outer diameter of the tip portion 7a.

  The bolt according to Patent Document 2 prevents the nut from being inadvertently dropped, but the recess 7b has a length larger than the thickness of the nut, and a protrusion that is unnecessary for fastening with the bolt and the nut. The unthreaded portion 7 is projected in a mischievous manner. For the purpose of preventing the fall of the nut, it is preferable to project the drop prevention protrusion with an appropriate length, and it may be considered to remove the drop prevention protrusion from the bolt after the nut is fastened to the bolt. .

  In addition, the bolt according to Patent Document 2 prevents the detached nut from being caught by the unthreaded portion 7 and inadvertently dropping the nut, but the side surface of the detached nut is caught by the step of the tip portion 7a. There is a problem that it cannot be removed smoothly from the bolt. For example, it may be considered to remove the nut from the bolt smoothly by eliminating the step of the tip portion 7a. These can be said to be the problems of the present invention.

  In view of such a problem, the present invention is a bolt capable of easily fitting and engaging a nut with a bolt without inadvertently dropping the nut, having a short projecting length from the bolt, and a nut. An object of the present invention is to provide a bolt that can be smoothly removed from the bolt.

  In order to achieve the above-mentioned object, the present inventor has a structure including a nut guiding portion for guiding a nut at a tip portion of a bolt, and has completed the following invention.

  (1) A bolt body having a bolt body having at least a head at one end and a threaded portion at the other end, and a body to be fastened by fastening a nut to the threaded portion. A nut guide portion having an outer diameter smaller than the inner diameter of the thread portion of the nut at a tip portion of the screw portion, and the nut guide portion includes one or more annular rings at which the nut is difficult to remove. Bolt with groove.

  In the bolt according to the invention of (1), the bolt body has at least a head at one end. The bolt body has a threaded portion at the other end. And a to-be-fastened body is fastened by a nut screwing in a screw part. The nut guiding part has an outer diameter smaller than the inner diameter of the threaded part of the nut, and a nut guiding part is provided at the tip of the threaded part of the bolt. The nut guiding portion has one or more annular grooves at the tip portion where it is difficult to remove the nut.

  The bolt applied to the present invention is a fastening part combined with a nut, includes a bolt having a head and a threaded portion, includes an implanted bolt having a threaded portion at both ends, and one end of the threaded portion is welded. Welding bolts (stud bolts) may be included. The bolt having the head portion and the screw portion includes a hexagon bolt and a square bolt, may include a hexagon socket head bolt, and may include a hexagon socket button bolt and a hexagon socket shoulder bolt. These bolts are preferably made of steel or stainless steel, and may be made of non-ferrous metal.

  The threaded portion according to the present invention includes a portion where a male screw is formed and includes a cylindrical portion where a male screw is not formed. Induction refers to guiding an object to a certain place or state. With the nut inserted into the nut guide, the nut is guided to the tip of the threaded portion, and the nut is easily fitted and engaged with the bolt. be able to. Since the nut is inserted into the nut guiding portion, the nut is not accidentally dropped. The length of the nut guiding portion is preferably equal to or greater than the thickness of the nut, but may be as long as the thickness of the nut. The length of the nut guiding portion can be at least shorter than the unthreaded portion that is the protrusion of the prior art shown in Patent Document 2.

  When the bolt according to the invention of (1) is moved in the direction in which the nut is inserted into the nut guiding portion and detached from the bolt, the thread of the female thread of the nut is locked in the annular groove and becomes a resistance. It becomes difficult to leave. Here, the annular groove may be a V-shaped or U-shaped groove, may be a square groove, or may be an arc-shaped groove, and one or more annular grooves are provided. A spiral groove may also be included in the annular groove. The annular groove is preferably provided to be biased toward the distal end side of the nut guiding portion, and preferably a non-grooved portion is provided between the base end portion of the nut guiding portion and the annular groove.

  When the nut is inserted in the nut guide portion and moved in the direction of detachment from the bolt, the thread of the female screw of the nut is locked in the annular groove to become resistance, so that the nut becomes difficult to detach. That is, careless dropping of the nut can be prevented. The bolt according to the invention of (1) can smoothly remove the nut from the nut guiding portion without the side surface of the detached nut being caught by the step of the tip portion as in the prior art disclosed in Patent Document 2.

  (2) The bolt according to (1), wherein the base end portion of the nut guide portion includes a conical portion that expands in a conical shape from the tip end side of the nut guide portion toward the base end portion.

  In the bolt according to the invention of (2), the base end portion of the nut guide portion is provided with a conical portion that expands conically from the tip end side of the nut guide portion toward the base end portion side. In a state where the nut is inserted into the guide portion, the nut is guided along the slope of the conical portion, and can be smoothly guided to the tip portion of the screw portion of the bolt. Then, the nut can be easily fitted and meshed with the bolt. For example, the nut can be easily engaged with the tip of the screw portion even in a dark place at hand.

  (3) The nut according to (1) or (2), wherein the nut guide portion is formed integrally with a screw portion of the bolt.

  In the bolt according to the invention of (3), since the nut guiding portion is formed integrally with the screw portion of the bolt, the manufacturing cost is low. For example, the integrated bolt may be manufactured by cutting or may be manufactured by forging.

  (4) The nut according to (1) or (2), wherein the nut guide portion is formed separately from the screw portion of the bolt.

  In the bolt according to the invention of (4), since the nut guiding portion is formed separately from the screw portion of the bolt, the nut guiding portion can be made detachable or the nut guiding portion can be easily sheared as will be described later. Is possible.

  (5) The nut according to (4), wherein the nut guide portion includes a pin that is formed to protrude from a base end portion of the nut guide portion, and the screw portion of the bolt has a hole into which the pin is fitted.

  A pin may be provided at the distal end portion of the screw portion of the bolt, and a hole for fitting the pin may be provided at the proximal end portion of the nut guiding portion.

  (6) The bolt according to (5), wherein the pin is press-fitted into the hole.

  Since the bolt according to the invention of (6) can be press-fitted so that the nut guide portion is screwed into the screw portion, it can be reliably coupled.

  (7) The bolt according to (5), wherein the pin is removably inserted into the hole.

  The bolt according to the invention of (7) can remove the nut guiding portion which becomes unnecessary after the nut is fastened to the bolt. The nut guiding portion may be left attached to the bolt so that the nut does not fall when the nut is loosened again.

  (8) The nut guide portion includes a pin that protrudes from the base end portion of the nut guide portion to form a male screw, and the screw portion of the bolt has a female screw hole to which the pin is screwed (4 ) Bolts described.

  The bolt according to the invention of (8) can remove the nut guiding portion that is no longer necessary after the nut is fastened to the bolt. The nut guiding portion may be left screwed to the bolt so that the nut does not fall when the nut is loosened again.

  (9) The bolt according to any one of (5) to (8), wherein the nut guide portion is made of metal, and a fixed end of the pin is formed so as to be easily sheared.

  The bolt according to the invention of (9) can shear an unnecessary nut guiding portion by applying an impact force from a direction perpendicular to the axial direction of the nut guiding portion after the nut is fastened.

  (10) The bolt according to any one of (4) to (8), wherein the nut guide portion is made of a synthetic resin.

  The bolt according to the invention of (10) can be reduced in weight because the nut guiding portion is made of synthetic resin. In addition, it is easy to make the nut guiding portion detachable.

  (11) The bolt according to any one of (4) to (9), wherein the nut guide portion is made of magnetized metal.

  In the bolt according to the invention of (11), when the nut is inserted in the nut guiding portion and moved in the direction of detachment from the bolt, the nut becomes difficult to detach because it becomes a resistance due to the magnetic attraction force.

  The bolt according to the present invention includes a nut guide portion having an outer diameter smaller than the inner diameter of the screw portion of the nut at the tip portion of the screw portion of the bolt, and the tip portion of the nut guide portion has one or more circles on which the nut is difficult to remove. Since it has an annular groove, the nut can be easily fitted and meshed with the bolt without inadvertently dropping the nut, facilitating fastening work at high places and in dark places at hand. It is convenient. And the length of a nut guidance part can be made at least shorter than the screwless part used as the projection of the prior art. Further, unlike the prior art, the nut can be smoothly removed from the nut guiding portion without the side surface of the removed nut being caught by the step at the tip portion.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a perspective external view showing a first embodiment of a bolt according to the present invention. FIG. 2 is an exploded perspective view showing a second embodiment of the bolt according to the present invention. FIG. 3 is a front view showing a use state of the bolt according to the first embodiment. FIG. 4 is a front view showing a use state of the bolt according to the second embodiment. FIG. 4 shows a cross section of the main part.

  First, the configuration of the bolt according to the present invention will be described. In FIG. 1, a bolt 1 according to the present invention includes a bolt body having a head 11 at one end and a threaded portion 12 at the other end. In the bolt 1, the fastened members A and B (see FIG. 3) are fastened when the nut 3 is screwed into the screw portion 12. The nut guide portion 13 is provided at the tip portion of the screw portion 12 and has an outer diameter smaller than the inner diameter of the screw portion 3 a of the nut 3. The distal end portion of the nut guide portion 13 includes one or more annular grooves 1a in which the nut 3 is difficult to remove. The base end portion of the nut guide portion 13 includes a conical portion 1c that expands in a conical shape from the tip end side of the nut guide portion 13 toward the base end portion.

  In FIG. 1, the bolt 1 is a hexagonal bolt including a hexagonal columnar head 11, but may be a square bolt including a quadrangular columnar head 11, and a hexagonal socket bolt having a hexagonal hole. Also good. Although a plurality of V-shaped annular grooves 1a are formed in the nut guiding portion 13, the annular groove 1a may be a female screw that becomes a spiral groove. The annular groove 1a is preferably provided to be deviated toward the distal end side of the nut guiding portion 13, and a non-grooved portion 1b is provided between the proximal end portion of the nut guiding portion 13 and the annular groove 1a. The screw portion 12 includes a male screw portion 1d where a male screw is formed, and includes a cylindrical portion 1e where a male screw is not formed.

  In FIG. 1, the nut guide portion 13 is formed integrally with the screw portion 12 of the bolt 1, and the manufacturing cost of the bolt 1 is reduced. For example, the integrated bolt 1 may be manufactured by cutting or may be manufactured by forging.

  In FIG. 2, the bolt 2 according to the present invention has a head portion 21 at one end portion and a screw portion 22 at the other end portion. The bolts 2 are fastened to the fastened members A and B (see FIG. 4) by the nuts 3 being screwed into the screw portions 22. The nut guide portion 23 is provided at the tip portion of the screw portion 22 and has an outer diameter smaller than the inner diameter of the screw portion 3 a of the nut 3. The distal end portion of the nut guide portion 23 is provided with one or more annular grooves 2a in which the nut 3 is difficult to remove. Further, the base end portion of the nut guide portion 23 includes a conical portion 2 c that expands in a conical shape from the tip end side of the nut guide portion 23 toward the base end portion.

  In FIG. 2, the bolt 2 is a hexagonal bolt including a hexagonal column-shaped head 21, but may be a square bolt including a quadrangular columnar head 21, and a hexagonal socket bolt having a hexagonal hole. Also good. Although a plurality of V-shaped annular grooves 2a are formed in the nut guide portion 23, the annular groove 2a may be a female screw serving as a spiral groove. The annular groove 2a is preferably provided to be biased toward the distal end side of the nut guiding portion 23, and a non-grooved portion 2b is provided between the base end portion of the nut guiding portion 23 and the annular groove 2a. The screw portion 22 includes a male screw portion 2d in which a male screw is formed, and includes a cylindrical portion 2e in which a male screw is not formed.

  In FIG. 2, the nut guide portion 23 is formed separately from the screw portion 22 of the bolt 2. Further, the nut guide portion 23 includes a pin 2 p that is formed to protrude from the base end portion of the nut guide portion 23. The screw portion 22 is provided with a hole 2h into which the pin 2p is fitted. The pin 2p may be formed so that it can be press-fitted into the hole 2h, and the nut guide portion 23 can be securely coupled to the screw portion 22. The pin 2p may be formed so as to be detachably inserted into the hole 2h. For example, the nut guiding portion 23 that is no longer necessary after the nut 3 is fastened to the bolt 2 can be removed.

  In FIG. 2, a male screw may be formed on a pin 2p that is formed to protrude from the base end portion of the nut guide portion 23, and the screw portion 22 of the bolt 2 may be provided with a female screw hole to which the pin 2p is screwed. The nut guiding portion 23 that is no longer necessary after the nut 3 is fastened to the bolt 2 can be removed. The nut guide portion 23 may be left screwed to the bolt 2 so that the nut 3 does not fall when the nut 3 is loosened again.

  Next, the operation of the bolt according to the present invention will be described.

  In FIG. 3, the nut 3 is guided to the tip of the screw portion 22 in a state where the nut 3 is inserted into the nut guide portion 13, and the nut 3 can be easily fitted and engaged with the bolt 1. Since the nut 3 is inserted into the nut guiding portion 13, the nut 3 is not accidentally dropped. The length of the nut guiding portion 13 is preferably equal to or greater than the thickness of the nut 3, but may be as long as the thickness of the nut 3. The length of the nut guiding portion 13 can be at least shorter than the unthreaded portion that is the protrusion of the prior art shown in Patent Document 2.

  In FIG. 3, when the nut 3 is moved in a direction to be detached from the bolt 1 from the state in which the nut 3 is inserted into the nut guide portion 13, the threads of the female thread of the nut 3 are locked in the plurality of annular grooves 1 a. In this way, when the nut 3 is inserted in the nut guide portion 13 and moved in the direction away from the bolt 1, the thread of the female screw of the nut 3 is locked to the annular groove 1a and becomes a resistance. Becomes difficult to leave. That is, inadvertent dropping of the nut can be prevented. Further, if the nut 3 is slightly separated from the plurality of annular grooves 1 a, the nut 3 can be removed from the nut guiding portion 13. As in the prior art disclosed in Patent Document 2, the nut 3 can be smoothly removed from the nut guiding portion 13 without the side surface of the removed nut being caught by the step at the tip portion.

  On the other hand, in FIG. 3, when the nut 3 is moved to the screw portion 12 side with the nut 3 inserted into the nut guide portion 13, the nut 3 is guided along the inclined surface of the conical portion 1c. It can be smoothly guided to the tip of the portion 12. Then, the nut 3 can be easily fitted and engaged with the bolt 1. For example, the nut 3 can be easily meshed with the tip of the screw portion 12 even in a dark place at hand. The fastened bodies A and B can be fastened with the bolts 1 and the nuts 3. In addition, since the volt | bolt 2 by 2nd Embodiment by which the nut induction | guidance | derivation part and the screw part were formed in the different body is the same as the above effect | action, description is abbreviate | omitted.

  The following modifications may be considered for the bolt 2 according to the second embodiment in which the nut guiding portion and the screw portion are formed separately. For example, in FIG. 4, the nut guide portion 23 may be made of metal, and the fixed end of the pin 2p may be formed so as to be easily sheared. In this way, by forming the pin 2p, an unnecessary nut guiding portion is formed by applying an impact force from the direction (in the direction of arrow X in the figure) perpendicular to the axial direction of the nut guiding portion 13 after the nut 3 is fastened. 23 can be sheared.

  In FIG. 4, the nut guide portion 23 is formed of a synthetic resin, so that the weight can be reduced and the nut guide portion 23 can be easily attached and detached. For example, the nut guiding portion 23 that has become unnecessary can be pulled out in the direction of the arrow Y in the figure. Furthermore, since the nut guiding portion 23 is made of magnetized metal, when the nut 3 is inserted in the nut guiding portion 23 and moved in the direction away from the bolt 2, the magnetic attraction force causes resistance. 3 becomes difficult to leave. This magnetized nut guiding portion 23 can exhibit a synergistic effect with the action of the annular groove 2a.

  As described above, the bolt applied to the present invention is a fastening part combined with a nut, and exemplifies a hexagonal bolt having a head and a screw portion. However, the technical idea of the present invention is a screw portion at both ends. It may be applied to an embedded bolt having a thread, a welding bolt to which one end of a threaded portion is welded, or may be applied to a support having an external thread at the end. Further, the bolt and the nut guiding portion may be integrated or separate, and either one is appropriately selected according to the necessity and use conditions.

1 is a perspective external view showing a first embodiment of a bolt according to the present invention. It is a perspective exploded view which shows 2nd Embodiment of the volt | bolt by this invention. It is a front view which shows the use condition of the volt | bolt by the said 1st Embodiment. It is a front view which shows the use condition of the volt | bolt by the said 2nd Embodiment. It is a side view which shows the volt | bolt by a prior art.

Explanation of symbols

1 ・ 2 Bolt 1a ・ 2a Ring groove 3 Nut 3a Screw part 11 ・ 21 Head part 12 ・ 22 Screw part 13 ・ 23 Nut guide part A ・ B Fastened body

Claims (11)

A bolt body having at least a head at one end portion and a bolt body having a screw portion at the other end portion, and a fastened body to be fastened by screwing a nut into the screw portion,
A nut guiding portion having an outer diameter smaller than the inner diameter of the thread portion of the nut is provided at the tip portion of the thread portion,
The nut guide part is a bolt provided with one or more annular grooves at the tip of which the nut is difficult to remove.   2. The bolt according to claim 1, wherein the base end portion of the nut guide portion includes a conical portion that expands in a conical shape from the tip end side of the nut guide portion toward the base end portion.   The bolt according to claim 1 or 2, wherein the nut guide portion is formed integrally with a screw portion of the bolt.   The bolt according to claim 1 or 2, wherein the nut guiding portion is formed separately from the screw portion of the bolt.   The bolt according to claim 4, wherein the nut guide portion includes a pin that protrudes from a base end portion of the nut guide portion, and the screw portion of the bolt has a hole into which the pin is fitted.   The bolt according to claim 5, wherein the pin is press-fitted into the hole.   The bolt according to claim 5, wherein the pin is detachably inserted into the hole.   The said nut guide part is provided with the pin which protrudes and forms from the base end part of the said nut guide part, and forms an external thread, The thread part of the said bolt provides the internal thread hole to which this pin is screwed. bolt.   The bolt according to any one of claims 5 to 8, wherein the nut guide portion is made of metal, and the fixed end of the pin is formed so as to be easily sheared.   The bolt according to any one of claims 4 to 8, wherein the nut guiding portion is made of a synthetic resin. The bolt according to claim 4, wherein the nut guiding portion is made of magnetized metal.

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