JP2022182982A - Single pipe clamp including screw rod with nut - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a single pipe clamp including a screw rod with a nut which can inhibit deterioration of workability even when operated by an electric tool such as an impact wrench.

SOLUTION: A screw rod 10 with a nut of a single pipe clamp 1 includes: a bolt part 12 in which a male screw 12a is formed on an outer peripheral surface; and a nut part 14 in which a female screw 14a is formed on an inner peripheral surface and which is threadedly engaged with the bolt part 12. An axial end part of the bolt part 12 is provided with a non-screw part 20 which is formed with no male screw. The inner peripheral surface of the nut part 14 is formed with a guide part 26 having a diameter larger than that of the male screw 12a of the bolt part 12. An outer diameter D1 of the non-screw part 20 is smaller than an outer diameter D2 of the male screw 12a and smaller than an inner diameter D4 of a thread 14aa of the female screw 14a.

SELECTED DRAWING: Figure 2

COPYRIGHT: (C)2023,JPO&INPIT

Description

TECHNICAL FIELD The present invention relates to a threaded rod with a nut used for fastening a single tube clamp.

Single-tube clamps are used to assemble scaffolds and to attach scaffolds to posts (eg, Patent Document 1). Such a single tube clamp has a fixed member formed with a recess for housing a single tube, and a movable member rotatably attached to the fixed member. Both members are clamped by a threaded rod with a nut.

Japanese Patent Application Laid-Open No. 2021-067013

With such a nutted threaded rod, the nut is loosened when the monotube pipe is removed from the clamp. At this time, if the nut is operated with an electric tool such as an impact wrench, the nut moves at a high speed. To overcome this problem, some bolts are provided with an enlarged diameter portion at the end to prevent the nut from coming off the bolt. Even in this case, if the stopping operation of the impact wrench is delayed, the high-speed and powerful thrust of the impact wrench is applied to the enlarged diameter portion through the nut, and there is a risk of damaging the enlarged diameter portion or the nut. For this reason, when operating the nut with an electric tool such as an impact wrench, it is necessary to pay sufficient attention to the timing of the end of the operation, which has been a factor in reducing workability.

SUMMARY OF THE INVENTION An object of the present invention is to provide a single tube clamp having a threaded rod with a nut that can suppress deterioration of workability even when operated with an electric tool such as an impact wrench.

In order to achieve the above object, the single pipe clamp of the present invention comprises: a fixing member having a recess for accommodating a pipe; A threaded rod with a nut provided with a movable member sandwiched between, a bolt portion having a male thread formed on the outer peripheral surface, and a nut portion having a female thread formed on the inner peripheral surface and screwed to the bolt portion I have. The threaded rod with nut is provided with a non-threaded portion having no male thread formed at the axial end of the bolt portion, and the inner peripheral surface of the nut portion has a diameter larger than the outer diameter of the male thread of the bolt portion. A guide portion having a large diameter is formed. The guide portion is positioned on the outer periphery of the male thread so that the center line of the male thread and the center line of the female thread are coaxial when the female thread is positioned on the outer periphery of the non-threaded portion. The non-threaded portion is provided at one axial end of the bolt portion, and the ring portion is provided at the other axial end. A ring portion of the threaded rod with nut is rotatably supported on one of the fixed member and the movable member, and a locking portion for locking the threaded rod with nut is formed on the other. The outer diameter of the non-threaded portion is smaller than the outer diameter of the male thread and smaller than the inner diameter of the thread of the female thread.

According to this configuration, since the non-threaded portion is provided at the end of the bolt portion, even if a power tool such as an impact wrench is used to rotate the nut portion at high speed, the nut portion idles when it reaches the non-threaded portion. Therefore, since the nut portion does not move further in the axial direction, it is possible to prevent the nut portion from coming off the bolt portion. As a result, workability is improved when loosening the nut portion.

If the entire nut portion reaches the non-threaded portion, when the nut portion is again tightened onto the bolt portion, there is a possibility that the nut portion will be tightened in a state where the axis of the nut portion is tilted with respect to the axis of the bolt portion. In this state, if the nut portion is rotated in the tightening direction by an electric tool such as an impact wrench, a biting error may occur between the male thread of the bolt portion and the female thread of the nut portion, and the male thread may be damaged. In the above configuration, the guide portion is formed on the inner peripheral surface of the nut portion. By fitting the guide portion to the outer circumference of the portion of the bolt portion where the male thread is formed, the axial center of the nut portion and the axial center of the bolt portion are aligned. As a result, even if a power tool is used to perform a rotation operation, a biting error will not occur between the male thread of the bolt portion and the female thread of the nut portion. As a result, workability is improved when refastening the nut portion.

In the present invention, an enlarged diameter portion having a larger diameter than the inner diameter of the nut portion may be formed at the end portion of the bolt portion provided with the non-threaded portion. According to this configuration, it is possible to effectively prevent the nut portion from falling off from the bolt portion by the expanded diameter portion. Also, as mentioned above, when the nut part reaches the non-threaded part when loosening the nut part, it will spin idle and the nut part will not move further in the axial direction. It is not added to the enlarged diameter portion through the As a result, workability is improved when loosening the nut portion.

In this case, the inner surface of the enlarged diameter portion axially facing the end surface of the nut portion may have a tapered surface that gradually decreases in diameter toward the end surface of the nut portion, that is, toward the male thread. . According to this configuration, the tapered surface of the enlarged diameter portion can prevent the axial center of the nut portion from inclining with respect to the axial center of the bolt portion. As a result, workability is improved when refastening the nut portion.

The manufacturing method of the threaded rod with nut used for the single tube clamp of the present invention includes:
a preparation step of preparing a shaft as a material of the bolt portion and the nut portion, providing the ring portion at one end of the shaft body, and forming the female thread and the guide portion by countersinking the nut portion; ,
a diameter-reducing step of forming a diameter-reduced portion constituting the non-threaded portion at the other end portion of the shaft by diameter-reducing processing;
a thread forming step of forming the external thread on the outer peripheral surface of the shaft body by thread rolling;
and a crimping step of forming the enlarged diameter portion at the other end of the shaft body by rotational crimping after the nut portion is screwed onto the male screw.

If a ring is provided at the end of the threaded rod with a nut, the ring may be deformed if the end of the shaft is crimped strongly. Since a rotary caulking process that does not apply a load to the ring is used, deformation of the ring portion can be suppressed.

According to the single tube clamp provided with the threaded rod with nut of the present invention, the workability when operating the nut portion is improved.

1 is a front view showing a single tube clamp having a threaded rod with a nut according to a first embodiment of the present invention; FIG. It is a front view of the threaded rod with the same nut. It is sectional drawing of the nut part of the threaded rod with a nut. It is a flow figure which shows the manufacturing procedure of the threaded rod with the same nut. It is a front view of the threaded rod with a nut of a comparative example.

Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram showing a single tube clamp provided with a threaded rod with a nut according to a first embodiment of the present invention. The single tube clamp 1 is used for assembling scaffolds, attaching supports to scaffolds, and the like. As shown in FIG. 1, the single tube clamp 1 of this embodiment is a single clamp provided with one threaded rod 10 with a nut as a fastener. However, the single tube clamp 1 is not limited to a single clamp, and may be an orthogonal clamp with two fasteners, a universal clamp, or a triple clamp with three fasteners.

A single tube clamp 1 includes a fixed member 2, a movable member 4, and a threaded rod 10 with a nut. The fixing member 2 is an L-shaped member having a concave portion 2a in which a single pipe (round pipe) P is accommodated. At both ends of the L-shaped fixing member 2, support shafts 6A and 6B extending in a direction perpendicular to the plane of the drawing are provided. Each support shaft 6A, 6B is fixed to the fixing member 2 by crimping both ends thereof, for example.

The movable member 4 is rotatably attached to the fixed member 2 . Specifically, the movable member 4 is rotatably mounted around one support shaft 6 (upper support shaft 6B in FIG. 1), that is, in the direction of arrow A1 in FIG. The movable member 4 is put on the outer side of the single pipe P housed in the recess 2 a and sandwiches the single pipe P between itself and the fixed member 1 . The movable member 4 of this embodiment is curved in an arc shape, more specifically, in a semicircular shape so as to cover the outer periphery of the single pipe P. As shown in FIG. The movable member 4 is rotatably connected to the fixed member 2 at one end (upper end in FIG. 1) of a semi-arc shape, and the other end (lower end in FIG. 1) is a free end.

A threaded rod 10 with a nut fixes the fixed member 2 and the movable member 4 . Specifically, the nut-equipped threaded rod 10 has a bolt portion 12 which is a round rod-shaped shaft having a male thread 12a formed on its outer peripheral surface, and a nut portion 14 having a female thread 14a formed on its inner peripheral surface. there is The nut part 14 of this embodiment is a flange nut in which a nut and a washer are integrated. However, the nut portion 14 is not limited to a flange nut.

The nut portion 14 is screwed onto the bolt portion 12 , and by rotating the nut portion 14 , the nut portion 14 moves in the axial direction AX of the bolt portion 12 . Specifically, when the nut portion 14 is moved to one side (left side in FIG. 1) in the axial direction AX, the nut portion 14 (threaded rod 10 with nut) is loosened, and when moved to the other side (right side in FIG. 1), the nut is loosened. A portion 14 (threaded rod 10 with a nut) tightens the movable member 4 .

A ring portion 16 is provided at the other end (the right end in FIG. 1) of the bolt portion 12 in the axial direction AX. The ring portion 16 of the present embodiment has an annular shape with an axis extending in a direction orthogonal to the axial direction AX of the bolt portion 12 (a direction orthogonal to the paper surface of FIG. 1).

A nut-equipped threaded rod 10 is rotatably supported by the fixed member 2 . Specifically, the nut-equipped threaded rod 10 is rotatably mounted around the other support shaft 6 (support shaft 6A on the lower side in FIG. 1), that is, in the direction of arrow A2 in FIG. More specifically, the movable member 4 is rotatably attached to the fixed member 2 by inserting the other support shaft 6A into the ring portion 16 of the threaded rod 10 with a nut.

A locking portion 18 to which the bolt portion 12 of the threaded rod 10 with nut is locked protrudes from the free end of the movable member 4 . The locking portion 18 is provided with a U-shaped locking groove 18a, and the bolt portion 12 can be locked to the locking groove 18a. The single pipe P is accommodated in the recess 2a of the fixed member 2, the movable member 4 and the threaded rod 10 with nut are rotated, and the bolt portion 12 of the threaded rod 10 with nut is engaged with the locking groove 18a of the movable member 4. stop. In this state, the pipe P can be fixed to the single pipe clamp 1 by tightening the bolt portion 14 (moving it to the right side in FIG. 1).

FIG. 2 shows the threaded rod 10 with a nut of this embodiment. A non-threaded portion 20 having no male thread is provided at one end (the left end in FIG. 2) of the bolt portion 12 in the axial direction AX. The outer diameter D1 of the non-threaded portion 20 is formed smaller than the outer diameter D2 of the male thread 12a. Here, the outer diameter D2 of the male screw 12a refers to the outer diameter (maximum allowable diameter) of the screw thread 12aa of the male screw 12a.

Specifically, the outer diameter D1 of the non-threaded portion 20 is formed smaller than the outer diameter D3 of the thread groove 12ab of the male thread 12a. That is, the outer diameter D1 of the non-threaded portion 20 is formed smaller than the inner diameter D4 ( FIG. 3 ) of the thread 14aa of the female thread 14a of the nut portion 14 . Therefore, when the nut portion 14 reaches the non-threaded portion 20, the nut portion 14 idles and does not move beyond the non-threaded portion 20 to the one end side even if the nut portion 14 is rotated.

Further, an enlarged diameter portion 22 having a larger diameter than the inner diameter of the nut portion 14 is formed at one end (the left end in FIG. 2) of the bolt portion 12 . Specifically, the enlarged diameter portion 22 is formed at the end of the bolt portion 12 where the non-threaded portion 20 is provided. That is, the bolt portion 12 is formed with a male thread 12a, a non-threaded portion 20, and an enlarged diameter portion 22 in this order toward one end. The expanded diameter portion 22 is formed, for example, by rotational crimping (spin crimping) for plastic deformation (diameter expansion) while rotating. However, the method of forming the enlarged diameter portion 22 is not limited to this. The outer diameter D5 of the expanded diameter portion 22 is formed larger than the inner diameter D4 (FIG. 3) of the thread 14aa of the internal thread 14a of the nut portion 14. As shown in FIG.

A tapered surface 24 whose diameter gradually decreases toward the other end is formed on the inner surface of the expanded diameter portion 22 . Here, the inner surface of the enlarged diameter portion 22 refers to a surface of the enlarged diameter portion 22 facing the end surface 14b (the left end surface in FIG. 2) of the nut portion 14 in the axial direction AX. That is, the tapered surface 24 gradually decreases in diameter toward the end surface 14b of the nut portion 14, that is, toward the male thread 12a.

Specifically, as shown in the enlarged view of part A in FIG. It is slanted so that That is, the tapered surface 24 of the enlarged diameter portion 22 and the chamfered surface 25 of the nut portion 14 are obliquely opposed to each other in the axial direction AX and formed substantially parallel to each other.

A guide portion 26 having a larger diameter than the male thread 12 a of the bolt portion 12 is formed on the inner peripheral surface of the nut portion 14 . An inner diameter D6 (FIG. 3) of the guide portion 26 is formed slightly larger than an outer diameter (maximum allowable diameter) D2 of the male screw 12 . Also, the length L1 of the guide portion 26 in the axial direction AX is, for example, the length of about two threads 12aa of the male screw 12a. However, the length of the nut portion 14 in the axial direction AX is not limited to this.

In this embodiment, the guide portion 26 is formed simultaneously with the internal thread 14a by counter boring. However, the method of forming the guide portion 26 is not limited to counter boring. The guide portion 26 is located on the outer periphery of the male thread 12a when the female thread 14a is located on the outer periphery of the non-threaded portion 20. As shown in FIG. As a result, even when the male thread 12a and the female thread 14a are no longer engaged, the center line AX of the male thread 12a (the axis of the bolt portion 12) and the center line AX1 of the female thread 14a are coaxial.

A procedure for manufacturing the threaded rod 10 with a nut according to the present embodiment will be described with reference to FIG. First, the shaft body 30 and the nut portion 14, which are the materials of the bolt portion 12, are prepared (preparation step). A ring portion 16 is provided at the other end (the right end in FIG. 4) of the shaft 30 . A female thread 14a (FIG. 3) and a guide portion 26 (FIG. 3) are formed in the nut portion 14 by counter boring.

Next, a diameter-reducing portion 20 is formed at one end (the left end in FIG. 4) of the shaft body 30 by diameter-reducing processing (diameter-reducing step). This reduced diameter portion 20 constitutes the non-threaded portion 20 . Further, the external thread 12a is formed on the outer peripheral surface of the shaft body 30 by thread rolling (thread forming step).

Subsequently, after the nut portion 14 is screwed onto the male thread 12a, the enlarged diameter portion 22 is formed by caulking at one end (the left end in FIG. 4) of the shaft body 30 (caulking step). In this embodiment, the expanded diameter portion 22 is formed by rotational crimping (spin crimping) for plastic deformation (diameter expansion) while rotating. The expanded diameter portion 22 may be formed by a crimping process other than rotational crimping, or may be formed by a processing method other than crimping. However, when the ring portion 16 is provided at the other end as in the present embodiment, the ring portion 16 may be deformed if the one end of the shaft body 30 is strongly struck for crimping. Therefore, in such a case, rotational crimping that does not apply a load to the ring portion 16 is preferable.

According to the above configuration, the non-threaded portion 20 is provided at one end of the bolt portion 12 shown in FIG. When the nut portion 14 reaches the non-threaded portion 20, it idles. Therefore, since the nut portion 14 does not move further toward the one end side, it is possible to prevent the nut portion 14 from coming off the bolt portion 12 . As a result, workability when loosening the nut portion 14 is improved.

As shown in FIG. 5 as a comparative example, when the nut portion 14 does not have a guide portion, when the nut portion 14 is loosened and the entire nut portion 14 reaches the non-threaded portion 20, the nut portion 14 is bolted again from there. When tightening the portion 12 , there is a possibility that the nut portion 14 is tightened with the axis AX<b>1 tilted with respect to the axis AX of the bolt portion 12 . If the bolt portion 12 is rotated by an electric tool such as an impact wrench in this state, a biting error may occur between the male thread 12a of the bolt portion 12 and the female thread 14a of the nut portion 14, and the male thread 12a may be damaged. .

In the embodiment of FIG. 2, since the guide portion 26 is formed on the inner peripheral surface of the nut portion 12, the guide portion 26 is fitted to the outer periphery of the male thread 12a of the bolt portion 12, thereby allowing the axis AX1 of the nut portion 14 to move. and the axis AX of the bolt portion 12 coincide. As a result, even if a power tool is used to rotate, the male thread 12a of the bolt portion 12 and the female thread 14a of the nut portion 14 will not bite into each other. As a result, workability when re-fastening the nut portion 14 is improved.

Moreover, since the enlarged diameter portion 22 is formed at one end of the bolt portion 12 , it is possible to effectively prevent the nut portion 14 from coming off the bolt portion 12 . As described above, when the nut portion 14 reaches the non-threaded portion 20 when the nut portion 14 is loosened, the nut portion 14 spins idle, and the nut portion 14 does not move further to the one end side. Thrust is not applied to the enlarged diameter portion 22 via the nut portion. As a result, workability when loosening the nut portion 14 is improved.

Further, the tapered surface 25 of the inner surface of the enlarged diameter portion 22 is inclined along the chamfer 25 of the end surface 14b of the nut portion 14. As shown in FIG. As a result, the axis AX<b>1 of the nut portion 14 can be prevented from tilting with respect to the axis AX of the bolt portion 12 . As a result, workability when re-fastening the nut portion 14 is improved.

The present invention is not limited to the above embodiments, and various additions, changes, or deletions are possible without departing from the scope of the present invention. For example, in the above embodiment, the non-threaded portion 20 was provided only at one end of the bolt portion 12 , but the non-threaded portion 20 may be provided at both ends of the bolt portion 12 .

In the above-described embodiment, the fixed member 2 rotatably supports the ring portion 16 of the nut-equipped screw rod 10, and the movable member 4 is provided with the locking portion 18 for locking the nut-equipped screw rod 10. However, the movable member 4 may rotatably support the ring portion 16 of the nut-equipped screw rod 10 , and the fixed member 2 may be formed with a locking portion 18 for locking the nut-equipped screw rod 10 .

Furthermore, in the above embodiment, an example in which the threaded rod 10 with a nut of the present invention is applied to the single pipe clamp 1 has been described, but the threaded rod 10 with a nut of the present invention can be applied to other than the single pipe clamp. Accordingly, such are also included within the scope of this invention.

1 single tube clamp 2 fixed member 2a concave portion 4 movable member 10 threaded rod with nut 12 bolt portion 12a male screw 14 nut portion 14a female screw 16 ring portion 18 locking portion 20 non-threaded portion 22 enlarged diameter portion 24 tapered surface 26 guide portion

Claims (4)

a fixing member having a recess in which the pipe is accommodated;
a movable member that is rotatably attached to the fixed member and sandwiches the pipe housed in the recess between itself and the fixed member;
A single-tube clamp comprising a threaded rod with a nut comprising a bolt portion having a male thread formed on its outer peripheral surface and a nut portion having a female thread formed on its inner peripheral surface and screwed onto the bolt portion, ,
The threaded rod with a nut is provided with a non-threaded portion having no external thread formed at an axial end of the bolt portion,
A guide portion having a larger diameter than the outer diameter of the male thread of the bolt portion is formed on the inner peripheral surface of the nut portion,
When the female thread is positioned on the outer periphery of the non-threaded portion, the guide portion is positioned on the outer periphery of the male thread so that the center line of the male thread and the center line of the female thread are coaxial,
The non-threaded portion is provided at one end in the axial direction of the bolt portion, and the ring portion is provided at the other end,
A ring portion of the threaded rod with a nut is rotatably supported by one of the fixed member and the movable member, and a locking portion for locking the threaded rod with a nut is formed on the other,
The outer diameter of the non-threaded portion is smaller than the outer diameter of the male thread and the inner diameter of the thread of the female thread. 2. A single tube clamp according to claim 1, wherein an enlarged diameter portion having a larger diameter than the inner diameter of said nut portion is formed at the end of said bolt portion where said non-threaded portion is provided. 3. The single tube clamp according to claim 2, wherein the inner surface of the enlarged diameter portion axially facing the end surface of the nut portion has a tapered surface whose diameter gradually decreases toward the end surface of the nut portion. Single tube clamp. A method for manufacturing the threaded rod with a nut used in the single tube clamp according to claim 2 or 3,
a preparation step of preparing a shaft as a material of the bolt portion and the nut portion, providing the ring portion at one end of the shaft body, and forming the female thread and the guide portion by countersinking the nut portion; ,
a diameter-reducing step of forming a diameter-reduced portion constituting the non-threaded portion at the other end portion of the shaft by diameter-reducing processing;
a thread forming step of forming the external thread on the outer peripheral surface of the shaft body by thread rolling;
a crimping step of forming the expanded diameter portion at the other end of the shaft body by rotational crimping after the nut portion is screwed onto the male thread;
A method of manufacturing a threaded rod with a nut.

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