JP2008274992A - Bolt with anti-loosening mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bolt with an anti-loosening mechanism having simple construction for maintaining constant anti-loosening effects over a long period even when applying repetitive fastening and removing operation thereto. <P>SOLUTION: The bolt 10 with the anti-loosening mechanism has a head part 12 and a body part 14 and is threaded to a fastened member. It comprises the anti-loosening mechanism for suppressing the looseness, after threaded. The bolt has a center hole 16. The center hole is formed ranging through the head part to a bottom 16b in the body part to store a soft metal rod member 18. It has a female screw 16s to be thread to a push-in member 20 which pushes the rod member into the center hole. The rod member is set so that its diameter is almost the same as or somewhat smaller than that of the center hole. After the bolt is threaded, the push-in member having a male screw is threaded to the center hole, and the rod member is pushed into the center hole until it is thrust while being held between a front end 20b of the push-in member and the bottom of the center hole. Thus, the diameter of the body part is enlarged to increase the threading force on the fastened member, suppressing the looseness. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a bolt for fastening and fixing a plurality of constituent members to each other in various mechanical devices, and more particularly to an improvement of a bolt locking prevention mechanism that can be repeatedly fastened and removed with a simple structure.

  Conventionally, as a member (machine element) for fastening and fixing a plurality of (for example, two) components to each other in various mechanical devices such as transport machines such as automobiles, airplanes and railway vehicles, various industrial machines and equipment, etc. Bolts are used very frequently. At that time, depending on the type of the mechanical device and the fastening portion, it may be necessary to reliably suppress the loosening of the bolt at a high level in order to ensure the safety. For this reason, various configurations have been conventionally known in which the bolt's male threaded portion is firmly screwed into a female threaded portion such as a screw hole or nut, and a locking mechanism is provided for the bolt in order to reliably prevent the bolt from loosening. It has been.

  However, in the locking mechanism disclosed so far, additional processing is required for the male screw portion of the bolt or the female screw portion such as a screw hole or a nut, and the cost for performing the additional processing is expensive. There were not a few cases where it ended up. In addition, since a part of the male screw part or the female screw part is damaged or irreversibly changed, the bolts are loosened after the components are fastened and fixed, or the apparatus is disassembled, or the bolts are removed from the apparatus. In many cases, it was difficult to reuse.

  For example, Patent Document 1 discloses a vertical hole (same as a hollow portion) 54 for inserting a predetermined pin member (hereinafter referred to as a lock center pin) 52 as shown in FIG. In addition, a horizontal hole (same as the lock ball hole) 58 for storing the fixing member (same as the lock ball) 56 is provided in the middle of the hollow part 54 in a direction perpendicular to the hollow part 54. A configuration example of the loosening prevention mechanism is disclosed.

According to the locking mechanism, the lock center pin 52 is inserted into the hollow portion 54 of the bolt 50 in advance, and the lock ball 56 is stored in the lock ball hole 58 in advance. For example, screw into a screw hole) and tighten. In this case, the lock center pin 52 is in a state in which the head 52 a protrudes from the opening of the hollow portion 54. Thereafter, the head 52 a of the lock center pin 52 inserted into the hollow portion 54 is hit with a hammer 60 or the like, and the lock center pin 52 is gradually pushed into the hollow portion 54.
At that time, the lock center pin 52 pushed into the hollow portion 54 comes into contact with the lock ball 56 housed in the lock ball hole 58 at the tip 52b, and the lock ball 56 is moved from the lock ball hole 58 in the horizontal direction. Extrude slightly (left and right in FIG. 3). Then, the lock ball 56 pushed out from the lock ball hole 58 is applied to a female screw of a screw hole (not shown), and as a result, the bolt 50 is in a state where the diameter of the lock ball 56 is expanded.

That is, since the lock ball 56 applied to the female screw (not shown) in the screw hole functions as a so-called stopper, the bolt 50 can be firmly fixed to the screw hole (not shown). It is possible to prevent the bolt 50 from loosening.
JP 9-329122 A

  However, in the locking mechanism disclosed in Patent Document 1, the lock ball 56 is applied (biting into) a female screw (not shown) in the screw hole, thereby tightening the bolt 50 against the screw hole (not shown). Therefore, the shape of the crest or trough of the female screw to which the lock ball 56 is applied may be deformed. For this reason, even if it is a case where the application | coating state of the lock ball 56 with respect to a female screw is cancelled | released, there exists a possibility that the bolt 50 cannot be loosened smoothly and the said bolt 50 cannot be easily removed from a screw hole. is there.

  In addition, in this way, the locking mechanism that applies the lock ball 56 to the female screw (not shown) (breaks in) causes the deformation of the locking ball 56 and the female screw when the locking mechanism is once released and then used again. For example, the initial locking accuracy cannot be maintained, and the locking accuracy is inevitably lowered. For this reason, the use of such a locking mechanism is basically limited to one time, and its versatility and durability are very poor.

  The present invention has been made to solve such a problem, and its purpose is not only to prevent the bolt from being loosened with a simple structure, but also to repeatedly perform fastening and removal of the bolt. An object of the present invention is to provide a bolt locking mechanism capable of maintaining a constant locking effect over a long period of time even when such fastening and removal are repeated.

  In order to achieve such an object, the bolt with a locking mechanism according to the present invention has a head that is engaged with a rotating jig to transmit a rotational force from the rotating jig, and a spiral on the outer periphery. And a female screw comprising a helical groove that is screwed with the male screw of the body part is screwed to a fastened member formed on the inner peripheral part, and A loosening prevention mechanism is provided for preventing loosening after screwing to the fastening member. In such a bolt with a locking mechanism, a central hole that is concentric with the shaft center is formed at the center thereof, and the central hole passes through the head and continues to a bottom portion provided in the body portion, An internal thread formed of a spiral groove is used to form a structure in which a soft metal rod-like member having elasticity is accommodated and to screw a pushing member for pushing the rod-like member toward the bottom of the center hole. The rod-shaped member has a structure formed in an inner peripheral portion, and the diameter of the rod-shaped member is set to be substantially the same as or slightly smaller than the diameter of the center hole. Then, after the bolt is screwed onto the member to be fastened, a pushing member having a male screw formed of a spiral groove screwed to the female screw formed in the central hole is formed on the outer peripheral portion. The rod-shaped member is pushed toward the bottom of the center hole by screwing, and the rod-shaped member is sandwiched and pressed between the distal end portion of the push-in member and the bottom portion of the center hole. The outer diameter is increased to increase the screwing force to the fastened member, thereby suppressing loosening.

  Further, the bolt with the locking mechanism according to the present invention has a center hole concentric with the shaft center at the center, and the center hole tapers from the head to the body, A female screw made of a spiral groove is formed on the inner peripheral portion for screwing a pushing member for pushing the rod-like member toward the tapered opening of the center hole. The maximum diameter of the rod-shaped member is set to be substantially the same as or slightly smaller than the maximum diameter of the center hole, and the center hole The taper shape is substantially the same as the taper shape. Then, after the bolt is screwed to the member to be fastened, a pushing member having a male screw formed of a spiral groove screwed with a female screw formed in the central hole is formed on the outer peripheral portion. The rod-shaped member is pushed into the taper-side opening of the center hole by screwing, and the outer peripheral portion of the rod-shaped member is pressed against the inner peripheral portion of the center hole, so that the outer diameter of the body portion is reduced. It is enlarged to increase the screwing force to the fastened member and suppress loosening.

  According to the bolt locking prevention mechanism of the present invention, not only the bolt locking can be prevented with a simple structure, but also the bolt can be repeatedly tightened and removed. In addition, even when such bolts are repeatedly tightened and removed, it is possible to maintain a certain locking prevention effect over a long period of time.

  Hereinafter, the bolt with a locking mechanism of the present invention will be described with reference to the accompanying drawings. Note that the bolt with a locking mechanism according to the present invention is configured such that a plurality of (for example, two) constituent members are mutually connected in various mechanical devices such as transportation machines such as automobiles, airplanes, and railway vehicles, and various industrial machines and devices. Since it can be applied as a member (mechanical element) to be fastened and fixed to, the use is not particularly limited here.

  1A to 1D show a bolt 10 with a locking mechanism (hereinafter simply referred to as a bolt) 10 according to a first embodiment of the present invention. The bolt 10 is a rotating jig (for example, , A wrench, a wrench, etc.) to engage the head 12 to which the rotational force from the rotating jig is transmitted, and the body 14 having a male screw 14s formed of a spiral groove on the outer periphery. Yes. The bolt 10 is screwed to a member to be fastened (screw hole, nut, etc.) formed on the inner peripheral portion of a female screw formed of a spiral groove to be screwed with the male screw 14s of the body portion 14, and the bolt to be fastened. The structure is such that the loosening after the screwing to the member is suppressed by a locking mechanism provided in the bolt 10 itself.

  In addition, in the structure shown to FIG.1 (a)-(d), although the head 12 is formed in the regular hexagon (regular hexagonal column) as an example, the shape is not specifically limited, The use condition of a bolt, What is necessary is just to set arbitrarily according to a use purpose or the shape of a to-be-fastened member. For example, a regular polygon other than a hexagon (regular polygonal column) may be formed, or a circle (cylinder) may be formed. Furthermore, it is good also as a structure which provided the concave hollow matched with the outline shape of rotating jigs, such as a wrench, in the head.

  1 (a) to 1 (d), the diameter of the head 12 is set larger than the diameter of the body portion 14, and the to-be-fastened member (screw hole, nut, etc.) not shown in the head 12 is shown. The bolt 10 is structured so as to come into contact with the peripheral edge of the member to be fastened when screwed into the head. However, the head 12 is configured such that its diameter dimension is necessarily set larger than the diameter dimension of the body part 14. It is not necessary, and the diameter dimensions of the head portion and the body portion are relatively set in accordance with the use condition and purpose of the mechanical device to which the bolt 10 is fastened, or in accordance with the size and shape of the member to be fastened. You only have to set it. For example, the diameter of the head is set to be approximately the same as the diameter of the body, and when screwing into a member to be fastened (such as a screw hole or nut), the head is buried in the member to be fastened together with the body. It may be a (contained) configuration (so-called potato-like configuration).

  Furthermore, the size of the head portion 12 and the size of the body portion 14 depend on the use conditions and purpose of the mechanical device to which the bolt 10 is fastened, or the size of a fastened member (not shown). Since it may be set arbitrarily, there is no particular limitation here. In addition, the shape, height (depth), pitch, and the like of the ridges and valleys constituting the male screw 14s of the body portion 14 are the same as those of the female screw formed on the inner peripheral portion of the fastened member (screw hole, nut, etc.). What is necessary is just to set arbitrarily according to the magnitude | size, shape, etc. of the volt | bolt 10 as long as screwing is possible.

  The bolt 10 is formed with a hole (hereinafter referred to as a center hole) 16 that is concentric with the shaft center at the center thereof, and the center hole 16 passes through the head 12 and is provided in the body portion 14. Further, a soft metal rod-like member (hereinafter referred to as a straight pin) 18 that is continuous with the bottom portion 16b and accommodates an elastic member is accommodated. That is, the center hole 16 is a non-through hole in which the opening 16a is positioned on the upper surface 12a of the head 12 (the upper surface in FIG. 1A) and the bottom 16b is positioned in the body portion 14. It is configured.

The center hole 16 has an internal thread 16s formed of a spiral groove for screwing a member 20 (hereinafter referred to as a pressing member) 20 for pressing the straight pin 18 toward the bottom 16b of the center hole 16. The structure formed in the peripheral part 16c is comprised.
In this case, the female screw 16s of the center hole 16 is formed on all of the head part of the center hole 16 and a part of the body part continuous to the head part, and its length (FIG. 1 (a) to FIG. 1). The distance in the vertical direction (d) is set to a dimension larger than the length of the pushing member 20.

  In addition, the pushing member 20 has a constant cylindrical shape from the base end portion 20 a to the tip end portion 20 b (from the upper end portion to the lower end portion in FIGS. 1B to 1D), and is formed in the center hole 16. A male screw 20s formed of a spiral groove screwed with the female screw 16s is formed on the outer peripheral portion. Accordingly, the pushing member 20 can be screwed into the center hole 16 by screwing the male screw 20 s with the female screw 16 s of the center hole 16.

  In this case, in order to engage a rotating jig such as a wrench, the base end portion 20a of the pushing member 20 has a concave recess (hereinafter referred to as an engagement hole) 20d that matches the outer shape of the rotating jig. When the pushing member 20 is screwed into the center hole 16, the rotating jig is engaged with the engaging hole 20d of the base end portion 20a in a predetermined direction (for example, clockwise). ). At this time, the pushing member 20 rotates together with the rotating jig in the same direction as the rotating jig, so that the pushing member 20 can be turned along the female screw 16 s of the center hole 16 and screwed into the center hole 16. . The size and shape of the engagement hole 20d are not particularly limited here because they may be set according to the size and outline shape of a rotating jig such as a wrench.

The straight pin 18 has a constant cylindrical shape from the base end portion 18a to the tip end portion 18b (the upper end portion to the lower end portion of FIGS. 1A to 1D), and the diameter size is set to the center hole 16. And the length (distance from the base end portion 18a to the tip end portion 18b) is set to the depth of the center hole 16 (from the opening 16a to the bottom portion 16b). The distance is set smaller than the distance).
As a result, the straight pin 18 inserts the distal end portion 18b into the central hole 16 from the opening 16a of the central hole 16 and applies a predetermined pressing force to the proximal end portion 18a. While making contact with the inner peripheral portion 16c (the female screw 16s and other portions), it is possible to move the tip portion 18b until it abuts against the bottom portion 16b of the center hole 16 (that is, push into the center hole 16). .

  In the bolt 10 having such a configuration, the front end portion 18b of the straight pin 18 is not in contact with the bottom portion 16b of the center hole 16 at a predetermined interval, and the base end portion 18a thereof is from the opening 16a of the center hole 16. In a state where the straight pin 18 is accommodated in the central hole 16 so that the upper surface 12a of the head 12 is recessed only in the central hole 16 without protruding, a to-be-fastened member (screw hole, nut, etc. not shown) ) And screwed to the fastened member (state shown in FIG. 1A).

After the bolt 10 is screwed to a member to be fastened (screw hole, nut, etc.), the distal end portion 20b of the pushing member 20 is inserted into the center hole 16 from the opening 16a of the center hole 16, and a rotating jig such as a wrench. Is engaged with the engagement hole 20d of the base end portion 20a. In this state, the rotating jig is rotated in a predetermined direction (for example, clockwise), and the pressing member 20 is rotated in the same direction together with the rotating jig, so that the pressing member 20 is connected to the female screw 16s of the center hole 16. It turns along and is gradually screwed into the said center hole 16 (state shown in FIG.1 (b)).
The pushing member 20 may be previously accommodated (screwed) together with the straight pin 18 in the center hole 16 when the bolt 10 is screwed to a member to be fastened (such as a screw hole or a nut).

  When the pushing member 20 is gradually screwed into the center hole 16 in this way, the pushing member 20 comes into contact with the proximal end portion 18a of the straight pin 18 whose tip portion 20b is accommodated in the center hole 16 in advance. (State shown in FIG. 1C). When the pushing member 20 is further screwed into the center hole 16 in a state where the distal end portion 20b is in contact with the proximal end portion 18a of the straight pin 18, the straight pin 18 receives a pressing force from the pushing member 20, and the center hole It moves toward the bottom 16b of 16 (it is pushed in).

  The straight pin 18 pushed in by the pushing member 20 is in a state in which the tip end portion 18b is in contact with the bottom portion 16b of the center hole 16 and is sandwiched between the bottom portion 16b and the tip end portion 20b of the pushing member 20. . In this state, when the pushing member 20 is further screwed into the center hole 16 and a pressing force is applied to the straight pin 18, the straight pin 18 is elastically deformed by the pressing force (specifically, diameter expansion deformation (expansion)). Then, the inner peripheral portion 16c of the center hole 16 is pressed in the diameter increasing direction (state shown in FIG. 1 (d)).

  As a result, the center hole 16 is elastically deformed and expanded in diameter, and the outer diameter of the body portion 14 of the bolt 10 is expanded elastically. That is, a member to be fastened (screw hole, nut, etc.) that is not shown in the figure when the external thread 14s formed on the outer peripheral portion of the expanded body portion 14 (particularly, the portion in which the straight pin 18 is accommodated) is screwed. The male screw 14s and the female screw are more strongly screwed together.

  Thereby, the force (screwing force) for screwing the bolt 10 to the fastened member (screw hole, nut, etc.) can be increased, and the loosening of the bolt 10 with respect to the fastened member can be reliably suppressed. .

  In the above-described embodiment, the specific material of the straight pin 18 is not particularly mentioned. However, the straight pin 18 is pushed into the center hole 16 by the pushing member 20, and the tip 20 b and the center hole 16 of the pushing member 20 are pushed. It is sandwiched between the bottom portion 16b and can be easily elastically deformed (specifically, diameter expansion deformation (expansion)), and the diameter of the center hole 16, that is, the body portion 14 can be increased. As long as it is a simple material, various materials can be arbitrarily selected according to the use condition or purpose of use of the mechanical device to which the bolt 10 is fastened. As an example, the straight pin 18 may be made of soft metal zinc.

  Further, when loosening the bolt 10, a rotating jig such as a wrench engaged with the engaging hole 20d of the pushing member 20 is rotated in a predetermined direction (for example, counterclockwise), and the pushing member 20 is moved to the center hole. It is swung along 16 female threads 16 s and gradually moved in the direction opposite to the screwing direction into the center hole 16 (that is, the removing direction (upward direction in FIGS. 1B to 1 D)). When the pushing member 20 is moved in this manner, the distal end portion 20b that is in contact with the proximal end portion 18a of the straight pin 18 is in a state of being separated from the proximal end portion 18a.

  As a result, the pressing force applied to the straight pin 18 from the pushing member 20 is released, and the straight pin 18 returns to its original state before elastic deformation (specifically, diameter expansion deformation (expansion)), and the center The inner peripheral portion 16c of the hole 16 is not pressed in the diameter increasing direction.

  Therefore, the center hole 16 can return to the original diameter before elastic deformation, and the outer diameter of the body portion 14 of the bolt 10 that has been elastically expanded can be returned to the original size before expansion. In other words, the male screw 14s formed on the outer peripheral portion of the body portion 14 (particularly, the portion in which the straight pin 18 is accommodated) is to be fastened (not shown) (screw hole, nut, etc.) with substantially the same force as when screwed. It can be set as the state screwed together with the female screw.

  Thereby, the bolt 10 once screwed to the member to be fastened (screw hole, nut, etc.) can be smoothly loosened and can be easily removed from the member to be fastened. Further, the bolt 10 removed from the member to be fastened is screwed to the member to be fastened again, and then the screwing force is increased by the same procedure as described above to loosen the bolt 10 with respect to the member to be fastened again. It is also possible to reliably suppress it.

  The bolt locking mechanism according to the present invention is not particularly limited to the configuration according to the above-described first embodiment (FIGS. 1A to 1D). Any configuration can be used according to the purpose of use. For example, even if it is the volt | bolt (bolt with a locking mechanism) 30 provided with the locking mechanism which concerns on 2nd Embodiment of this invention shown to Fig.2 (a)-(d), it is the volt | bolt 10 which concerns on 1st Embodiment. It is possible to obtain the same effect (that is, the loosening prevention effect) of suppressing looseness with respect to the fastened member (screw hole, nut, etc.).

  FIGS. 2A to 2D show a bolt 30 according to a second embodiment of the present invention. The bolt 30 is the bolt 10 according to the first embodiment described above (FIG. 1A). (D)), a head 12 to which a rotating jig (for example, a spanner or a wrench) is engaged to transmit a rotational force from the rotating jig, and a spiral groove on the outer periphery. The body part 14 is formed with a male screw 14s. In this case, since the basic configuration of the bolt 30 is the same as that of the bolt 10 described above, the same or similar configuration as the bolt 10 is denoted by the same reference numeral on the drawing, and the description is omitted or simplified. Below, the characteristic structure of the volt | bolt 30 which concerns on this embodiment is demonstrated.

  As shown in FIGS. 2A to 2D, the bolt 30 has a hole (hereinafter referred to as a center hole) 36 concentric with the shaft center formed at the center thereof. The head part 12 and the trunk | drum 14 are penetrated in the taper shape. In this case, the center hole 36 has a constant diameter dimension up to the head 12 and a part of the body part 14 continuous with the head part 12, and the front end surface of the body part 14 from the part (FIG. 2A). ˜ (d) lower surface) 14b is gradually reduced in diameter so that a metal rod-like member (hereinafter referred to as a taper pin) 38 is accommodated. That is, the center hole 36 has a maximum diameter opening (hereinafter referred to as an upper opening) 36 a on the upper surface 12 a of the head 12, and a minimum diameter opening (the same as the lower opening) in the distal end surface 14 b of the body portion 14. 36b is positioned.

Further, in the center hole 36, a female screw 36s formed of a spiral groove is formed in the inner peripheral portion 36c in order to screw the pressing member 20 for pressing the taper pin 38 toward the lower opening 36b of the center hole 36. The structure is made.
In this case, the female screw 36s of the center hole 36 is formed in all of the head part of the center hole 36 and a part of the body part continuous to the head part, and its length (FIG. 2 (a) to FIG. 2). The distance in the vertical direction (d) is set to a dimension larger than the length of the pushing member 20.

  The pushing member 20 has a constant cylindrical shape from the proximal end portion 20a to the distal end portion 20b (the upper end portion to the lower end portion in FIGS. 2B to 2D), and is formed in the center hole 36. A male screw 20s formed of a spiral groove screwed with the female screw 36s is formed on the outer peripheral portion. Accordingly, the pushing member 20 can be screwed into the center hole 36 by screwing the male screw 20 s into the female screw 36 s of the center hole 36.

  The taper pin 38 has a proximal end portion 38a (upper end portion in FIGS. 2A to 2D) having a maximum diameter and a distal end portion 38b (lower end portion in FIG. 2) having a minimum diameter, and the distal end from the proximal end portion 38a. It forms a tapered truncated cone shape whose diameter is gradually reduced to the portion 38b. In this case, the maximum diameter dimension (the diameter dimension of the base end portion 38a) is set to be substantially the same as or slightly smaller than the maximum diameter dimension of the center hole 36 (the diameter dimension of the upper opening 36a). In addition, the central hole 36 is configured to have a tapered shape substantially the same as the shape of a tapered portion (hereinafter referred to as a tapered portion) 36t. Further, the length of the taper pin 38 (distance from the base end portion 38a to the tip end portion 38b) is set to be smaller than the depth of the center hole 36 (distance from the upper opening 36a to the lower opening 36b). It is configured.

  As a result, the taper pin 38 inserts the distal end portion 38b from the upper opening 36a of the center hole 36 into the center hole 36, and applies a predetermined pressing force to the proximal end portion 38a, thereby centering a part of the outer peripheral portion 38c. While being in contact with the inner peripheral portion 36c (the female screw 36s and other portions) of the hole 36, it is possible to move until the tip end portion 38b reaches the vicinity of the lower opening 36b (that is, push into the center hole 36). Become.

  The bolt 30 having such a configuration is such that the tip end surface 38b of the body portion 14 is recessed in the center hole 36 without the tip end portion 38b of the taper pin 38 reaching the lower opening 36b of the center hole 36, and the base In a state where the taper pin 38 is accommodated in the center hole 36 so that the end 38a does not protrude from the upper opening 36a of the center hole 36 and the upper surface 12a of the head 12 is recessed only by the center hole 36, A member to be fastened (not shown) (screw hole, nut, etc.) is screwed and screwed to the member to be fastened (state shown in FIG. 2A).

After the bolt 30 is screwed into a member to be fastened (screw hole, nut, etc.), the distal end portion 20b of the pushing member 20 is inserted into the center hole 36 from the upper opening 36a of the center hole 36, and a wrench or the like is rotated. The tool is engaged with the engagement hole 20d of the base end portion 20a. In this state, the rotating jig is rotated in a predetermined direction (for example, clockwise), and the pressing member 20 is rotated in the same direction together with the rotating jig, so that the pressing member 20 is connected to the female screw 36s of the center hole 36. It turns along and is gradually screwed into the said center hole 36 (state shown in FIG.2 (b)).
The pushing member 20 may be previously accommodated (screwed) together with the taper pin 38 in the center hole 36 when the bolt 30 is screwed to a member to be fastened (screw hole, nut, or the like).

  When the pushing member 20 is gradually screwed into the center hole 36 in this way, the pushing member 20 comes into contact with the proximal end portion 38a of the taper pin 38 whose tip portion 20b is previously accommodated in the center hole 36 ( (The state shown in FIG. 2 (c)). When the pushing member 20 is further screwed into the center hole 36 in a state where the distal end portion 20b is in contact with the proximal end portion 38a of the taper pin 38, the taper pin 38 receives a pressing force from the pushing member 20 and It moves toward the lower opening 36b (it is pushed in).

  When the tip end portion 38b reaches the vicinity of the lower opening 36b of the center hole 36, the taper pin 38 pushed by the pushing member 20 has a substantially entire outer peripheral portion 38c substantially tapered to the tapered portion of the inner peripheral portion 36c of the center hole 36. It will be in the state made to contact 36t. In this state, when the pushing member 20 is further screwed into the center hole 36 and a pressing force is applied to the taper pin 38, substantially the entire outer peripheral portion 38c comes into strong contact with the tapered portion 36t of the inner peripheral portion 36c of the center hole 36. Then, the tapered portion 36t is pressed in the diameter increasing direction (state shown in FIG. 2D). That is, a state similar to a state in which the taper pin 38 is driven as a so-called wedge with respect to the taper portion 36t of the center hole 36 is obtained.

  As a result, the center hole 36 is elastically deformed and expanded in diameter, and the outer diameter of the body portion 14 of the bolt 30 is expanded elastically. That is, the male screw 14s formed on the outer peripheral portion of the enlarged body portion 14 (particularly, the portion in which the taper pin 38 is accommodated) is a member to be fastened (screw hole, nut, etc.) not shown in the drawing. The male screw 14s is firmly pressed against the female screw, and the male screw 14s and the female screw are screwed together more strongly.

  Thereby, the force (screwing force) for screwing the bolt 30 to the fastened member (screw hole, nut, etc.) can be increased, and the loosening of the bolt 30 to the fastened member can be reliably suppressed. .

  In the above-described embodiment, the specific material of the taper pin 38 is not particularly mentioned. However, the pressing member 20 is pushed into the center hole 36, and the entire outer peripheral portion 38c is a tapered portion 36t of the center hole 36. As long as it is a material that can maintain a certain rigidity without being deformed even if it is strongly abutted against the center hole 36, and can expand the diameter of the central hole 36, that is, the body portion 14. Various materials can be arbitrarily selected according to the use conditions and purpose of use of the mechanical device to which the bolt 10 is fastened. As an example, the taper pin 38 is assumed to be made of a predetermined metal, but is not a soft metal (as an example, zinc) like the straight pin 18 according to the first embodiment of the present invention, but a hard metal. It is preferable that it is manufactured.

  When the bolt 30 is loosened, a rotating jig such as a wrench engaged with the engaging hole 20d of the pushing member 20 is rotated in a predetermined direction (for example, counterclockwise), and the pushing member 20 is moved to the center hole. It is swung along the female screw 36s of 36 and gradually moved in the direction opposite to the screwing direction into the center hole 36 (that is, the removing direction (upward direction in FIGS. 2B to 2D)). Thereby, the pushing member 20 is positioned so that the distal end portion 20b that is in contact with the proximal end portion 38a of the taper pin 38 is separated from the proximal end portion 38a by a predetermined distance.

Next, an unillustrated extrusion jig (for example, a cylindrical member set to have substantially the same diameter as the tip portion 38b of the taper pin 38) is applied to the tip portion 38b of the taper pin 38 from the lower opening 36b of the center hole 36, The taper pin 38 having the tip 38b applied to the extrusion jig is moved to the upper opening 36a of the center hole 36 by hitting the extrusion jig toward the center hole 36 with a hammer (eg, a hammer shown in FIG. 3). It moves toward (more specifically, toward the front-end | tip part 20b of the pushing member 20).
As a result, the outer peripheral portion 38c of the taper pin 38 does not press the tapered portion 36t of the center hole 36, and the outer peripheral portion 38c comes into gentle contact with the tapered portion 36t.

  Therefore, the center hole 36 can return to the original diameter before elastic deformation, and the outer diameter of the body portion 14 of the bolt 30 that has been elastically expanded can be returned to the original size before expansion. That is, the male screw 14s formed on the outer peripheral portion of the body portion 14 (particularly, the portion in which the taper pin 38 is accommodated) is a member to be fastened (screw hole, nut, etc.) (not shown) with substantially the same force as that at the time of screwing. It can be set as the state screwed with the internal thread.

  Thus, the bolt 30 once screwed to the member to be fastened (screw hole, nut, etc.) can be smoothly loosened and can be easily removed from the member to be fastened. Further, the bolt 30 removed from the member to be fastened is screwed to the member to be fastened again, and then the screwing force is increased by the same procedure as described above to loosen the bolt 30 with respect to the member to be fastened again. It is also possible to reliably suppress it.

  In such a bolt loosening prevention mechanism according to the second embodiment of the present invention, the body portion 14 of the bolt 30 is exposed to the outside after the front end surface 14b is screwed to the fastening member (not shown). In this case, for example, when the member to be fastened is a nut, the configuration is very effective. That is, since the front end surface 14b of the body portion 14 is exposed to the outside after being screwed to a member to be fastened (for example, a nut), the taper pin 38 is moved toward the upper opening 36a of the center hole 36 by the pushing jig. The work to move can be performed easily. That is, the operation (adjustment) of the screwing force of the bolt 30 can be easily performed, and the fastening and removing of the bolt 30 can be easily repeated.

  As described above, according to the locking mechanism according to the first embodiment and the second embodiment of the present invention, not only can the bolts 10 and 30 be prevented from locking with a simple structure, but also the bolts 10 and 30 can be prevented. Fastening and dismounting can be repeated. In addition, even when such bolts 10 and 30 are repeatedly fastened and removed, a certain locking prevention effect can be maintained over a long period of time.

  In the first embodiment and the second embodiment of the present invention described above, the length of the pushing member 20 is such that the distal end portion 20b abuts the proximal end portion 18a of the straight pin 18 accommodated in the center hole 16. In such a state, the base end portion 20a is not projected from the opening 16a of the center hole 16, or the base end portion 20b is in contact with the base end portion 38a of the taper pin 38 accommodated in the center hole 36. The end 20 a is set to a dimension that does not protrude from the upper opening 36 a of the center hole 36.

For this reason, the push-in member 20 may remain in the center hole 16 or the center hole 36 as it is or may be removed after completion of the locking operation for the bolts 10 and 30. For example, in order to increase the rigidity of the bolts 10 and 30 (and the mechanical device), it is preferable to leave the pushing member 20 remaining. On the other hand, in order to reduce the weight of the bolts 10 and 30 (and the mechanical device), it is preferable to remove the pushing member 20.
Therefore, the handling of the push-in member 20 after completion of the work for preventing the bolts 10 and 30 from being loosened may be freely determined according to the use conditions and purpose of use of the mechanical device to which the bolts 10 and 30 are fastened.

It is a figure which shows the structural example of the volt | bolt with a locking mechanism which concerns on 1st Embodiment of this invention, Comprising: (a) shows the state by which the volt | bolt which accommodated the straight pin in the center hole was screwed by the to-be-fastened member. (B) is a mechanism diagram showing a state in which the pushing member is screwed into the center hole, (c) is a mechanism diagram showing a state in which the pushing member is in contact with the straight pin, and (d) is a diagram showing that the straight pin is The mechanism figure which shows the state which is expanding and deform | transforming and is pressing the inner peripheral part of a center hole to the diameter expansion direction. It is a figure which shows the structural example of the volt | bolt with a locking mechanism which concerns on 2nd Embodiment of this invention, Comprising: (a) is a mechanism which shows the state in which the volt | bolt which accommodated the taper pin in the center hole was screwed to the to-be-fastened member. (B) is a mechanism diagram showing a state in which the pushing member is screwed into the center hole, (c) is a mechanism diagram showing a state in which the pushing member is in contact with the taper pin, and (d) is an outer peripheral portion of the taper pin. The mechanism figure which shows the state which contact | abuts strongly to a center hole and is pressing the taper part in the diameter-expanding direction. The mechanism figure which shows the structural example of the volt | bolt with a conventional locking mechanism.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Bolt 12 with a locking mechanism Head part 14 Body part 14s Body part male screw 16 Center hole 16b Center hole bottom part 16s Center hole female thread 18 Bar-shaped member (straight pin)
20 Pushing member 20b Pushing member tip

Claims (2)

It is composed of a head part that engages the rotating jig and transmits the rotational force from the rotating jig, and a body part in which an external thread made of a spiral groove is formed on the outer periphery, A female screw comprising a helical groove to be screwed is screwed to a member to be fastened formed on the inner periphery, and is provided with a loosening prevention mechanism for preventing loosening after screwing to the member to be fastened. A bolt with a stop mechanism,
The bolt is formed with a central hole concentric with the axial center at the center thereof, and the central hole passes through the head and continues to a bottom portion provided in the body portion, and has elasticity. In order to form a structure in which a metal rod-like member is accommodated and to screw a pushing member for pushing the rod-like member toward the bottom of the center hole, a female screw made of a spiral groove is formed on the inner peripheral portion. Comprising the formed structure, the rod-shaped member has a diameter dimension set to be substantially the same as or slightly smaller than the diameter dimension of the central hole,
After the bolt is screwed to the member to be fastened, a push-in member having a male screw formed of a spiral groove to be screwed with the female screw formed in the central hole is screwed into the central hole. By pushing the rod-shaped member toward the bottom of the center hole, the rod-shaped member is sandwiched and pressed between the distal end portion of the push-in member and the bottom of the center hole, and the outer diameter of the body portion A bolt with a locking mechanism, wherein the bolt is increased in size to increase the screwing force with respect to the fastened member to suppress loosening. It is composed of a head part that engages the rotating jig and transmits the rotational force from the rotating jig, and a body part in which an external thread made of a spiral groove is formed on the outer periphery, A female screw comprising a helical groove to be screwed is screwed to a member to be fastened formed on the inner peripheral portion, and is provided with a locking mechanism for preventing loosening after screwing to the member to be fastened. A bolt with a stop mechanism,
The bolt has a central hole formed concentrically with the shaft center at the center thereof, and the central hole tapers from the head to the body portion to receive a metal rod-shaped member. And has a structure in which a female screw formed of a spiral groove is formed on the inner peripheral portion for screwing a pushing member for pushing the rod-like member toward the tapered opening of the center hole. The rod-shaped member has a maximum diameter dimension that is set to be substantially the same as or slightly smaller than the maximum diameter dimension of the center hole, and a tapered shape that is substantially the same as the tapered shape of the center hole. And
After the bolt is screwed to the member to be fastened, a push-in member having a male screw formed of a spiral groove to be screwed with the female screw formed in the central hole is screwed to the central hole. By pushing the rod-shaped member toward the taper-side opening of the center hole, the outer peripheral portion of the rod-shaped member is pressed against the inner peripheral portion of the center hole, so that the outer diameter of the body portion is enlarged. The bolt with a locking mechanism is characterized in that the screwing force to the fastened member is increased to prevent loosening.

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