JP4920063B2 - tightening structure - Google Patents

Description

  The present invention is a fastening structure that is used when a worker's hand, tool, or the like does not reach the back side of a plate-like member from the side of the worker performing the fastening operation when fastening the plate-like members using bolts. It is about.

  Conventionally, as shown in FIGS. 6 to 8, the operator's hand, tool, or the like cannot reach the area on the left side of the drawing from the two plate-like members 6 and 8 stacked in the thickness direction. However, by using the bolt 4 having a special structure, the fastening operation between the plate-like members 6 and 8 can be performed only from the region on the right side of the plate-like members 6 and 8. There has been a fastening structure 2 that can manage the tightening torque (see, for example, Patent Document 1).

  As shown in FIG. 6, the bolt 4 used in this conventional fastening structure 2 has a male thread portion 10 formed at one end and a pin tail 12 formed at the other end. Further, on the same axis line between the male thread part 10 and the pin tail 12, another pin tail 14 and another male thread part 16 are formed in this order from the pin tail 12 side.

  As shown in FIGS. 6 to 8, the bolt 4 penetrates the through hole 18 of the plate-like member 8 while the pin tails 12 and 14 are removed in stages in order to manage the tightening torque. The male screw portion 10 is screwed to the screw hole 20 of the plate-like member 6, and the nut 24 is screwed to the male screw portion 16 via the washer 22.

  In the conventional fastening structure 2, as shown in FIG. 6, when the male screw portion 10 of the bolt 4 is fastened to the screw hole 20 of the plate-like member 6, like a shear wrench engaged with the pin tail 12 of the bolt 4. Since the internal socket 27 of the tightening tool 26 rotates and tightens until the pin tail 12 is twisted, the tightening torque between the male screw portion 10 and the screw hole 20 can be appropriately managed. It was.

  Also, after tightening the male screw portion 10 of the bolt 4 into the screw hole 20 of the plate-like member 6 and removing the pin tail 12, the work of tightening the male screw portion 16 and the nut 24 of the bolt 4 as shown in FIG. In this case, when the tubular socket 28 of the clamping tool 26 that rotates by engaging with the nut 24 reaches a predetermined tightening torque, only the inner socket 27 that engages with the pin tail 14 rotates. By continuing, the pin tail 14 is twisted off (see FIGS. 7 and 8). As a result, the tightening torque between the male screw part 16 and the nut 24 is appropriately managed.

Japanese Patent Laid-Open No. 7-27120

  However, in the above-described conventional fastening structure 2, as shown in FIG. 6, the pin tail 12 of the bolt 4 is attached during the fastening operation between the male screw portion 10 of the bolt 4 and the screw hole 20 of the plate-like member 6. The tightening torque that can be twisted is considered to have been sufficiently tightened, but this tightening torque is processed by the male screw portion 10 of the bolt 4 or the screw hole 20 of the plate-like member 6. When the accuracy is low, it may occur before the completion of tightening, and thus there is a problem that an appropriate screwing depth of the male screw portion 10 is not necessarily guaranteed.

  Further, in the conventional fastening structure 2 described above, the male screw portion 10 of the bolt 4 is screwed to the screw hole 20 of the plate-like member 6 to its root, and a simple round bar-like portion where the male screw of the root is not formed is formed. When the pin tail 12 is twisted off by interfering with the female screw of the screw hole 20 and screw connection is not completed, the screw connection is completed. There is a risk of crushing. At this time, there is a problem that the screw coupling length between the male screw portion 10 of the bolt 4 and the screw hole 20 of the plate-like member 6 is insufficient.

  Therefore, in view of the above problems, the present invention can be used when an operator's hand, tool, or the like does not reach the back side of the thick part of the plate-like member to be tightened. It is an object of the present invention to provide a fastening structure in which a bolt to be fastened can be reliably screw-coupled by an appropriate length and can surely exhibit appropriate axial strength.

In order to solve the above problems, the fastening structure according to the present invention is:
A bolt in which a first male screw portion is formed at one end, a second male screw portion at the other end, and a barrel portion having a diameter larger than at least the diameter of the first male screw portion is formed at an intermediate portion;
A first plate member formed with a through hole having a larger diameter than the body of the bolt ;
A second plate member joined with a stepped nut,
The barrel portion of the bolt is inserted through the through hole of the first plate member ,
A first male screw portion of the bolt, a state in which the a female screw portion of the stepped nut joined to the second plate member, the end face of the end face of the first male screw portion side of the body portion and the stepped nut abuts in concluded,
A nut is fastened to the second male screw portion.

The fastening structure according to the present invention is
A pin tail having a tool fitting groove at the tip is formed at the end of the second male screw of the bolt.

According to such a fastening structure of the present invention,
A bolt in which a first male screw portion is formed at one end, a second male screw portion at the other end, and a barrel portion having a diameter larger than at least the diameter of the first male screw portion is formed at an intermediate portion;
A first plate member formed with a through hole;
A second plate member joined with a stepped nut,
The first male screw portion of the bolt inserted into the through hole of the first plate member and the female screw portion of the stepped nut joined to the second plate member are fastened, and the nut is fastened to the second male screw portion. By doing
It can be used when an operator's hand or tool does not reach the back side of the thick part of the first plate member and the second plate member to be tightened, and between the first plate member and the second plate member The bolt for fastening the screw can surely be screw-coupled by an appropriate length and can surely exert an appropriate axial strength.

Moreover, according to the fastening structure of the present invention,
By forming a pin tail having a tool fitting groove at the tip at the end of the second male thread of the bolt,
The tightening torque between the second male thread portion of the bolt and the nut can be appropriately managed, and the tightening operation of the bolt can be facilitated.

It is side surface sectional drawing which shows the fastening structure 30 which concerns on the 1st Embodiment of this invention. 3 is a side cross-sectional view showing one state of a fastening structure 30. FIG. It is the front view which looked at the volt | bolt 36 shown in FIG. 2 from the pin tail 46 side. 3 is a side cross-sectional view showing a part of the fastening structure 30 and the fastening tool 58. FIG. It is side surface sectional drawing which shows the fastening structure 70 which concerns on the 2nd Embodiment of this invention. It is side surface sectional drawing which shows one state of the conventional fastening structure 2 and the fastening tool 26. FIG. It is side surface sectional drawing which shows the other state of the fastening structure 2 and the fastening tool 26. FIG. It is side surface sectional drawing which shows only the fastening structure 2. FIG.

Hereinafter, the form for carrying out the fastening structure concerning the present invention is explained concretely based on a drawing.
FIGS. 1 to 4 are views referred to for explaining a fastening structure 30 according to a first embodiment of the present invention.

  As shown in FIG. 1, a fastening structure 30 according to the present embodiment includes a front side plate member 32 (corresponding to a first plate member) and a back side plate member 34 (corresponding to a second plate member), a bolt 36 and a hexagon nut. It is tightened by 38 screw connections. Each of the front side plate member 32 and the back side plate member 34 has a thickness in the left-right direction in FIG.

  Here, in the fastening structure 30, when the hexagon nut 38 is fastened to the bolt 36, the worker is in the right region of the front side plate member 32 in FIG. 1 and works from there. . And the left side area | region of the back side board member 34 in FIG. 1 shall be in the condition where an operator's hand and tool cannot reach.

  The bolt 36 has a first male screw portion 40 formed at the left end in FIG. 1 and a second male screw portion 42 formed at the right end. The bolt 36 is formed such that the diameter (outer diameter) of the body portion 44 between the first male screw portion 40 and the second male screw portion 42 is at least larger than the outer diameter of the first male screw portion 40.

  The bolt 36 includes a pin tail 46 formed at the distal end portion of the second male screw portion 42 as shown in FIG. 2 until the hexagon nut 38 is tightened. As will be described later, The pin tail 46 is removed during the tightening operation. Further, as shown in FIG. 3, a cross groove 48 (tool fitting groove) capable of engaging the tip of a tool such as a Phillips screwdriver is formed on the tip surface of the pin tail 46.

  As shown in FIG. 1, the front side plate member 32 is formed with a through hole 50 for passing the bolt 36. The back side plate member 34 is formed with a fitting hole 52 at a position corresponding to the position of the through hole 50 of the front side plate member 32. A stepped nut 54 is fitted into the fitting hole 52 from the side opposite to the front plate member 32, and is tightly press-fitted and fitted inside the fitting hole 52 so as not to idle.

Next, the procedure of each operation between the bolt 36 and each member will be described.
First, as shown in FIG. 2, the tip end portion of the first male screw portion 40 of the bolt 36 is inserted into the through hole 50 of the front side plate member 32 from the opening on the right side thereof, and the screw hole 54a (female screw) of the stepped nut 54 is inserted. Screw).

  The first male screw portion 40 of the bolt 36 is screwed in until the end surface of the body portion 44 on the first male screw portion 40 side hits the end surface of the stepped nut 54. By abutting in this way, the first male screw portion 40 of the bolt 36 can be reliably screw-coupled by an appropriate length. This operation is performed by engaging and rotating the tip portion of a tool such as a Phillips screwdriver in the cross groove 48 on the tip surface of the pin tail 46 shown in FIG.

  Next, as shown in FIG. 4, in the second male screw portion 42 of the bolt 36, a length portion protruding outward from the front side surface (the right side surface in the drawing) of the front side plate member 32, via a washer 56, The hexagon nut 38 is screwed.

  The operation of screwing the hexagon nut 38 to the second male screw portion 42 is performed using a tightening tool 58 having a hexagonal recess such as a shear wrench. The tightening tool 58 is a tool including a tubular socket 60 that engages with the hex nut 38 and an inner socket 62 that engages with the pin tail 46 through a number of grooves. The tubular socket 60 and the inner socket 62 are arranged coaxially so that they can rotate independently of each other.

  The tightening tool 58 is configured such that only the tubular socket 60 is rotated and the hexagon nut 38 is tightened in a state where the inner socket 62 is engaged with the pin tail 46 and the rotation thereof is restricted. Therefore, only the axial force acting only in the axial direction is generated in the bolt 36 by the tightening action of the hexagon nut 38, so that the shearing force due to the twist about the axis that reduces the axial strength of the bolt 36 is not generated. It has become.

  When the tubular socket 60 for tightening the hexagon nut 38 stops rotating even when a predetermined magnitude of torque is applied (when the tightening torque reaches a predetermined magnitude), the tightening tool 58 By starting and continuing the rotation, the pin tail 46 of the bolt 36 is twisted and removed.

  According to this embodiment, when the operator's hand, tool, or the like cannot reach the back side of the thick portion of the front side plate member 32 and / or the back side plate member 34 to be tightened by the fastening structure 30. Further, the male thread portion 40 of the bolt 36 that fastens between the plate members 32 and 34 can be screwed together by an appropriate length, and the bolt 36 ensures an appropriate axial strength. Can be demonstrated.

  Further, according to the present embodiment, the pintail 46 is formed at the end of the second male screw portion 42 of the bolt 36, so that the tightening torque between the second male screw portion 42 of the bolt 36 and the hexagon nut 36 is appropriately set. Can be managed.

  Further, according to the present embodiment, since the cross groove 48 is formed at the tip of the pin tail 46 of the bolt 36, the tip of a tool such as a Phillips screwdriver is engaged with the cross groove 48 and rotated. Therefore, the bolt 36 can be easily tightened.

  Next, FIG. 5 is a figure referred in order to demonstrate the fastening structure 70 which concerns on the 2nd Embodiment of this invention.

  FIG. 5 is a diagram showing a state in the middle of tightening the bolt 72 used in the present embodiment, and is a diagram showing a state immediately before the pin tail 46 is removed after the hexagon nut 38 is tightened.

  In the present embodiment, a stepped fitting hole 74 is formed in the back side plate member 34, and a large diameter portion and a small diameter portion of the stepped nut 54 are provided in a large diameter portion and a small diameter portion of the stepped fitting hole 74. Each is press-fitted to fit.

  According to the present embodiment, in addition to having the same effect as the first embodiment, the entire stepped nut 54 is fitted in the stepped fitting hole 74 of the back plate member 34. As a result, the two portions of the large diameter portion and the small diameter portion of the stepped nut 54 are press-fitted into the two large diameter portions and the small diameter portion of the stepped fitting hole 74. It is possible to prevent the stepped nut 54 from rotating together with the bolt 72.

  In addition, since the large diameter portion of the stepped nut 54 does not protrude outward from the back side (left side in FIG. 5) surface of the back side plate member 34 as in the first embodiment, the large diameter portion of the stepped nut 54 is provided. Can be prevented from interfering with other members.

  In addition, although the cross groove 48 was formed as a tool fitting groove | channel on the front end surface of the pin tail 46 of the volt | bolts 36 and 72 which concern on the said embodiment, it replaces with this cross groove 48, and a tool like a minus driver. A slot such as a hexagonal hole that engages the tip of a tool such as a hexagon wrench, or a slot that engages the tip of the tool may be formed.

2 Fastening Structure 4 Bolt 6, 8 Member 10 Male Thread Part 12, 14 Pin Tail 16 Male Thread Part 18 Through Hole 20 Screw Hole 22 Washer 24 Nut 26 Tightening Tool 27 Internal Socket 28 Tubular Socket 30 Fastening Structure 32 Front Side Plate Member 34 Back Side Plate Member 36 Bolt 38 Hexagon nut 40 First male screw part 42 Second male screw part 44 Body 46 Pin tail 48 Cross groove 50 Through hole 52 Fitting hole 54 Stepped nut 54a Screw hole 56 Washer 58 Tightening tool 60 Tubular socket 62 Internal socket 70 Fastening structure 72 bolt 74 stepped fitting hole

Claims (2)

A bolt in which a first male screw portion is formed at one end, a second male screw portion at the other end, and a barrel portion having a diameter larger than at least the diameter of the first male screw portion is formed at an intermediate portion;
A first plate member formed with a through hole having a larger diameter than the body of the bolt ;
A second plate member joined with a stepped nut,
The barrel portion of the bolt is inserted through the through hole of the first plate member ,
A first male screw portion of the bolt, a state in which the a female screw portion of the stepped nut joined to the second plate member, the end face of the end face of the first male screw portion side of the body portion and the stepped nut abuts in concluded,
A fastening structure characterized in that a nut is fastened to the second male screw portion.   The fastening structure according to claim 1, wherein a pin tail having a tool fitting groove at a tip portion is formed at an end portion of the second male screw portion of the bolt.

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