WO2018168162A1

WO2018168162A1 - Connection fitting and coupling tool

Info

Publication number: WO2018168162A1
Application number: PCT/JP2017/047187
Authority: WO
Inventors: 正樹有賀
Original assignee: 株式会社キトー
Priority date: 2017-03-17
Filing date: 2017-12-28
Publication date: 2018-09-20
Also published as: JP2018155343A; JP6735699B2

Abstract

Provided is a connection fitting that has a curved beam section having a cross-section which is circular even near a groove-shaped arm, capable of coupling another member in a pivotable manner, and capable of sufficiently ensuring the strength of the curved beam section. The connection fitting 10 is provided with: an inserting arm section 20 provided with a through hole 21 into which a connecting pin 100 is inserted; a groove-shaped arm section 30 that is provided with through holes 33a, 33b into which the connecting pin 100 is inserted, and that is positioned at one end side in the width direction facing the inserting arm section 20 positioned at the other end side; and a curved beam section 50 provided between the inserting arm section 20 and the groove-shaped arm section 30. The curved beam section 50 is provided with a circular cross-section along the entirety in the extension direction; an arcuate projection part 40, which reduces the extension length of the curved beam section 50, is provided between the curved beam section 50 and the groove-shaped arm section 30; and the thickness dimension in the thickness direction orthogonal to the width direction in a cross-section of the arcuate projection part 40 is provided so as to be greater than the diameter of the cross-section of the curved beam section 50.

Description

Coupling brackets and couplers

The present invention relates to a coupling fitting and a coupling tool coupled to a chain.

For example, when connecting a hook to be loaded to a chain, the hook is often connected to the chain via a coupling fitting. Examples of such coupling fittings include those disclosed in Patent Documents 1 to 4.

Patent Documents 1 to 3 disclose a configuration in which a curved beam portion exists between an insertion arm portion and a groove-shaped arm portion. The bent beam portion is a portion to which a connection object such as a chain is connected. Here, when the position of the chain in the rotation direction with respect to the coupling bracket when the coupling bracket and the chain are hanging under a natural load is the hanging position, the chain connected to the curved beam section is along the curved beam section. It is slidable away from the hanging position.

On the other hand, although the cross-sectional shape of the curved beam portion is close to a circle, it is provided in an elliptical shape that gradually becomes flattened toward the groove-shaped arm portion. Therefore, when the amount of rotation from the hanging position of the chain increases and the chain reaches the bending beam portion near the groove-shaped arm portion, the chain cannot move in the rotation direction and the sliding direction. Such a state in which the chain cannot move is called chain entanglement.

Further, Patent Document 4 discloses a coupling fitting in which the cross section of the bent beam portion is flat (see FIG. 9). In this configuration, when the chain is in the suspended position, the chain is slidable along the bent beam portion, but the chain cannot be rotated from the suspended position with respect to the bent beam portion.

Japanese Patent No. 5732379 JP 2000-46123 A Japanese Examined Patent Publication No. 63-35861 US2014 / 0290206

By the way, in the configuration of Patent Document 4, the chain cannot be rotated with respect to the bending beam portion, so that the chain can be prevented from being tangled. However, when a force in the direction of rotating the chain is applied, a large bending moment is applied to the bent beam portion, which is not preferable. That is, it is preferable that the chain can be freely rotated from the hanging position with respect to the bending beam portion.

On the other hand, in the configurations disclosed in Patent Documents 1 to 3, when the chain is positioned in the vicinity of the insertion arm portion, the chain can freely rotate from the hanging position. However, if the chain rotates with the chain positioned in the vicinity of the channel arm, the chain will be tangled.

In recent years, the strength of the chain has been improved, and the diameter of the metal part of the chain has been reduced accordingly. In that case, since the diameter of the ring hole surrounded by the metal ring of the chain is also reduced, it is necessary to reduce the diameter of the bent beam portion. Here, in the configurations disclosed in Patent Documents 1 to 3, it is necessary to sufficiently secure the strength even if the bending beam portion has a small diameter. For this reason, in the configurations disclosed in Patent Documents 1 to 3, the strength of the bent beam portion is ensured by forming the bent beam portion so that the cross section of the bent beam portion becomes elliptical toward the groove-shaped arm portion. Therefore, in the configurations disclosed in Patent Documents 1 to 3, it is difficult to eliminate the entanglement of the chain when the chain is positioned in the vicinity of the groove-shaped arm portion.

The present invention has been made in view of the above circumstances, and the cross-section of the curved beam portion is circular even in the vicinity of the groove-shaped arm portion, and other members can be connected in a rotatable state, and the strength of the curved beam portion is also provided. An object of the present invention is to provide a coupling fitting capable of sufficiently securing the above.

In order to solve the above-described problem, according to the first aspect of the present invention, a coupling fitting is constituted by being coupled to another coupling fitting via a coupling pin, and the coupling pin is inserted. An insertion arm portion having a through hole, an insertion hole into which the connecting pin is inserted, a grooved arm portion positioned on the other end side facing the insertion arm portion positioned in the one end side in the width direction, and an insertion A curved beam portion provided between the telescoping arm portion and the groove-shaped arm portion, and the curved beam portion is provided with a circular cross section perpendicular to the extending direction over the entire extending direction, and is bent. Between the beam part and the channel-shaped arm part, an arc-like overhang part is provided to reduce the extension length of the curved beam part, and the thickness dimension in the thickness direction perpendicular to the width direction in the cross section of the arc-like overhang part Is provided larger than the diameter of the cross section of the curved beam portion. Alloy tool is provided.

Further, in another aspect of the present invention, in the above-described invention, it is preferable that the inner peripheral portion of the arc-shaped projecting portion constitutes a part of an arc-shaped locus that is continuous with the curved beam portion.

Furthermore, in another aspect of the present invention, in the above-described invention, the front surface and the back surface located on both end sides in the thickness direction of the arc-shaped projecting portion are the front surface and the back surface located on both end sides in the thickness direction of the groove-shaped arm portion. It is preferable that they are provided flush.

Moreover, the other side surface of this invention is a coupling tool used as a cyclic | annular form by connecting two coupling metal fittings which concern on the invention mentioned above, Comprising: The insertion arm part of one coupling metal fitting of two coupling metal fittings And the insertion hole of the groove arm part of one of the two fittings, and the insertion hole of one of the two fittings. The through hole of the insertion arm part of the other coupling metal of the two coupling metal is aligned, and in this alignment state, the connecting pin is inserted into the through hole and the insertion hole, so that the two coupling metal It is preferred that they are linked.

According to the present invention, in the joint fitting, the cross section of the bending beam portion is circular even in the vicinity of the groove-shaped arm portion, and other members to be connected are rotatable, and sufficient strength of the bending beam portion is ensured. Is possible.

It is a top view which shows the structure of the coupling metal fitting which concerns on one embodiment of this invention. It is a perspective view which shows the state which comprised the coupling tool with which the coupling metal fitting shown in FIG. It is a front view which shows the state which looked at the coupling metal fitting shown in FIG. 1 from the insertion arm part and the groove-shaped arm part side. FIG. 2 is a cross-sectional view showing a state in which the coupling fitting is cut along the line II in FIG. 1. It is a side view which shows the state which looked at the coupling metal fitting shown in FIG. 1 from the insertion arm part side. It is a side view which shows the state which looked at the coupling metal fitting shown in FIG. 1 from the groove-shaped arm part side. FIG. 2 is a transverse cross-sectional view showing a state where a coupling fitting is cut along the line II-II in FIG. 1. It is a perspective view which shows the mode of the stress concentration of the insertion arm part side among the present coupling metal fittings as a comparative example. It is a perspective view which shows the mode of the stress concentration by the groove-shaped arm part side among the present coupling | joint metal fittings as a comparative example. It is a perspective view which shows the mode of the stress concentration of the insertion arm part side among the coupling metal fittings of this Embodiment. It is a perspective view which shows the mode of the stress concentration by the groove-shaped arm part side among the coupling metal fittings of this Embodiment.

Hereinafter, a coupling fitting 10 according to an embodiment of the present invention will be described with reference to the drawings. In the following description, an XYZ orthogonal coordinate system will be used as necessary. In the XYZ orthogonal coordinate system, the X direction is the axial direction of the connecting pin 100 in FIG. 2, the X1 side indicates the right side in FIG. 2, and the X2 side indicates the opposite left side. In addition, the Y direction refers to a direction in which the insertion arm portion 20 and the grooved arm portion 30 extend while being orthogonal to the X direction (width direction) in FIGS. 1 and 2, and the Y1 side corresponds to FIGS. 1 and 2. The Y2 side indicates the front side of the paper surface in FIGS. 1 and 2. Further, the Z direction (thickness direction) indicates a direction orthogonal to the X direction and the Y direction, the Z1 side indicates the back side of the paper surface in FIG. 3, and the Z2 side indicates the near side of the paper surface in FIG.

<About the configuration of the fittings>
FIG. 1 is a plan view showing the configuration of the coupling fitting 10. FIG. 2 is a perspective view showing a state in which a connector 11 in which a pair of coupling fittings 10 are connected is configured.

As shown in FIG. 2, the pair of coupling fittings 10 are connected via a connecting pin 100. The connecting pin 100 connects the pair of fittings 10 by inserting the connecting pin 100 in a state where a through-hole 21 and an

insertion hole

33a, 33b, which will be described later, are aligned. One end of the connecting pin 100 and the other end are slightly thicker than the central portion. One end and the other end are located in the through hole 21 and the

insertion holes

33a and 33b, respectively, and a cylindrical spring collar 110 is attached to the central portion of the connecting pin 100.

The inner diameter of the hole of the spring collar 110 is slightly larger than the inner diameter of the through hole 21, and a spring for tightening the connecting pin 100 when it is press-fitted is provided inside the hole. Therefore, the spring collar 110 is attached to the central portion of the connecting pin 100, thereby preventing the connecting pin 100 from coming out of the through hole 21.

The coupling fitting 10 constituting the connecting tool 11 as described above is made of a metal such as steel. Further, as shown in FIG. 1, the coupling fitting 10 includes an insertion arm portion 20, a groove-shaped arm portion 30, an arcuate overhang portion 40, and a bending beam portion 50, and each of these portions is, for example, It is integrally formed by forging. The coupling fitting 10 includes a surrounding hole S1 surrounded by these parts, and an external chain, a link member, or the like is inserted into the surrounding hole S1.

FIG. 3 is a front view showing a state in which the coupling fitting 10 is viewed from the insertion arm portion 20 and the grooved arm portion 30 side. FIG. 4 is a cross-sectional view showing a state in which the coupling fitting 10 is cut along the line II in FIG. FIG. 5 is a side view showing a state in which the coupling fitting 10 is viewed from the insertion arm portion 20 side.

As shown in FIG. 1 and FIG. 5, the insertion arm portion 20 is a portion located on one end side of the coupling metal 10 and is a portion inserted into the groove portion 32 of the groove-shaped arm portion 30. As shown in FIG. 5, in the insertion arm portion 20, the outer peripheral surface on the Y1 side is an arc surface 22 that draws an arc. As shown in FIGS. 3 and 4, the Z1 side outer peripheral surface of the insertion arm portion 20 is also an arc surface 23, and it follows the ring hole surrounded by the metal ring when the chain is inserted. Can do. When such a circular arc surface 23 exists, the strength can be improved as compared with a case where the circular arc surface 23 does not exist. However, the outer peripheral surface on the Z2 side is not an arc surface, and the outer peripheral surface is provided in a flat shape. However, at least one of the outer peripheral surfaces on the Z1 side and the Z2 side may be an arc surface, and the outer peripheral surfaces on both the Z1 side and the Z2 side may be flat instead of the arc surface.

In addition, the outer peripheral surface (the outer peripheral surface on the X1 side and the outer peripheral surface on the X2 side) on both sides in the width direction (X direction) of the insertion arm portion 20 is formed in a flat shape. Further, the cross-sectional area of the insertion arm portion 20 is provided so as to be larger than that of the bending beam portion 50.

As shown in FIGS. 1 and 3 to 5, the insertion arm portion 20 is provided with a dimension (thickness dimension) in the Z direction larger than that of the bending beam portion 50. However, the insertion arm portion 20 is provided with a dimension (width dimension) in the X direction smaller than that of the bending beam portion 50. Thereby, the insertion arm portion 20 can be inserted into the ring hole surrounded by the metal ring of the chain, and the chain can be positioned at the bending beam portion 50. Further, since the dimension (width dimension) in the X direction is reduced, the insertion arm part 20 is easily positioned in the groove part 32.

The insertion arm portion 20 is provided with a through hole 21. The through hole 21 penetrates the insertion arm portion 20 along the width direction (X direction), and is a portion for positioning one end portion of the connecting pin 100 described above. Of the outer peripheral surfaces of the insertion arm portion 20 on the Z1 side and Z2 side, an inclined portion 24 is also provided on the bending beam portion 50 side (Y2 side), and the insertion arm portion 20 and the bending beam portion 50 are provided. There is no step between them.

FIG. 6 is a side view showing the state in which the coupling fitting 10 is viewed from the grooved arm 30 side. As shown in FIG. 1, the groove-shaped arm portion 30 is a portion located on the other end side of the coupling fitting 10. This groove-shaped arm part 30 has a pair of opposing

piece parts

31a and 31b along the thickness direction (Z direction), and the insertion arm part 20 is inserted between these opposing

piece parts

31a and 31b. A groove 32 to be inserted is provided. Therefore, the width dimension of the groove part 32 (opposite distance between the opposing piece part 31 a and the opposing piece part 31 b) is an interval corresponding to the insertion of the insertion arm part 20.

As shown in FIG. 3 and FIG. 4, insertion holes 33 a and 33 b are provided in the respective facing

pieces

31 a and 31 b. The insertion holes 33 a and 33 b penetrate the opposing

piece portions

31 a and 31 b along the width direction (X direction), and are formed so as to be coaxial with the through hole 21. These insertion holes 33 a and 33 b are portions for positioning the other end of the connecting pin 100. The insertion holes 33a and 33b are provided at the center in the thickness direction (Z direction) of the opposing

piece portions

31a and 31b, but are provided at positions slightly shifted from the center in the thickness direction (Z direction). Also good.

In the groove-shaped arm portion 30, the outer peripheral surface on the Y1 side is an arc surface 34 that draws an arc, but a flat shape other than the arc surface 34 may be used.

Further, as shown in FIGS. 3, 4, and 6, the opposing

piece portions

31 a and 31 b are provided with dimensions (thickness dimensions) in the Z direction larger than that of the insertion arm portion 20. Therefore, the opposing

piece portions

31 a and 31 b (groove-shaped arm portion 30) are portions having a larger dimension in the thickness direction (Z direction) than the bent beam portion 50. Further, in a state where the insertion arm portion 20 is positioned in the groove portion 32, the insertion arm portion 20 is protected by the opposing

piece portions

31a and 31b.

FIG. 7 is a cross-sectional view showing a state in which the fitting 10 is cut along the line II-II in FIG. As shown in FIGS. 1, 6, and 7, the arc-shaped projecting portion 40 is continuously provided on the Y2 side of the groove-shaped arm portion 30. The protruding amount in the thickness direction (Z direction) of the arcuate projecting portion 40 with respect to the curved beam portion 50 is one side (Z1 side) in the thickness direction (Z direction) and the other side (Z2 side) in the thickness direction (Z direction). It is about the same. However, these protrusion amounts may be different. The inner peripheral portion of the arc-shaped protruding portion 40 constitutes a part of an arc-shaped locus. Therefore, the inner peripheral portion of the arcuate overhanging portion 40 is a portion constituting the surrounding hole S1 of the coupling fitting 10 together with the inner peripheral portion of the bent beam portion 50. In other words, due to the presence of the arcuate projecting portion 40, the length of the bent beam portion 50 is short.

As shown in FIG. 1, in the present embodiment, a line L2 that passes through the center of the surrounding hole S1 and reaches the end portion 40a on the Y2 side of the arcuate overhanging portion 40, and the center of the surrounding hole S1, while passing in the Y direction. Is preferably in the range of 45 to 60 degrees. Within this range, for example, when a pair of chains are slung over the surrounding hole S1, it is possible to ensure a sufficient opening angle between the chains. Moreover, the dimension of the bending beam part 50 can be shortened and the stress concentration in the maximum stress concentration part 51 mentioned later can be reduced.

Here, as shown in FIG. 7, the arcuate overhanging portion 40 is provided with a thickness dimension M1 (dimension in the Z direction) larger than the diameter D1 of the curved beam portion 50, and the groove-shaped arm portion 30. The thickness dimension (dimension in the Z direction) is approximately the same. The thickness dimension M1 is provided within a range of about 2 to 2.5 times the diameter D1. Further, the surface on the Z1 side and the back surface on the Z2 side of the arcuate overhanging portion 40 are provided so as to be flush with the surface on the Z1 side and the back surface on the Z2 side of the grooved arm portion 30. Therefore, the arcuate overhanging portion 40 has a large cross-sectional area and is a portion that is difficult to deform even when a load is applied to the bending beam portion 50. Moreover, in the arc-shaped overhang | projection part 40, the stress in the inner peripheral part which faces the surrounding hole S1 can be reduced.

Further, the bent beam portion 50 is an arc-shaped beam portion located between the insertion arm portion 20 and the arc-shaped protruding portion 40, and is a portion to which a load from a chain or a link member acts. The curved beam portion 50 has a circular cross section, and is provided so as to have the same diameter over the entire circumferential direction. Therefore, when a chain is hung on the bending beam portion 50, the chain can be slid along the bending beam portion 50, and the chain rotates at any position in the circumferential direction of the bending beam portion 50. It is possible to move. For this reason, it is possible to prevent the chain from being entangled in any part of the bent beam portion 50.

<Regarding stress concentration>
The state of stress concentration related to the joint fitting 10 having the above configuration will be described below. FIG. 8 is a perspective view showing a state of stress concentration on the insertion arm portion 20C side in the current coupling fitting 10C as a comparative example. FIG. 9 is a perspective view showing a state of stress concentration on the grooved arm portion 30C side in the current coupling fitting 10C as a comparative example.

8 and 9, the Y direction is arranged along the vertical direction in the coupling fitting 10C, and the load portion 53C that intersects the center line L1 on the inner peripheral side of the bending beam portion 50C is arranged. A load is applied to the lower side in the vertical direction (Y2 side).

8 and 9, in the vicinity of the groove-shaped arm portion 30C of the bent beam portion 50C, the cross section of the bent beam portion 50C is not a perfect circle but is an ellipse or an ellipse. Therefore, when the chain is positioned on the grooved arm portion 30C side in the bending beam portion 50C, the chain is tangled.

8 and 9 are formed so as to be hardened as a whole by applying heat treatment such as quenching or other treatments in order to improve the strength. In addition, when the material becomes hard, scratches and the like formed at the time of processing can become the starting point of fatigue failure. For example, the processing accuracy of the through holes 21 and the

insertion holes

33a and 33b is improved by using a reamer or the like. Etc. are prevented. In addition, in the coupling fitting 10C, the surface thereof is subjected to cationic coating, and the coating film thickness is made thinner than other coatings. As a result, the range in which the chain is entangled on the side of the grooved arm portion 30C of the bent beam portion 50C is reduced as much as possible. However, the entanglement cannot be completely eliminated, and in a part of the range. It is in a state where tangling occurs.

As shown in FIG. 8, in the current coupling metal fitting 10C, the bending moment is maximized at the inner peripheral side portion on the Y1 side adjacent to the insertion arm portion 20C in the bending beam portion 50C, and the inner peripheral side thereof. This portion is deformed so as to have a larger curvature radius, and is also distorted vertically downward by a load, so that the maximum stress concentration portion 51C where stress is most concentrated is obtained. As an example, when a certain load was applied, the stress at the maximum stress concentration portion 51C was 628 N / mm ² . Further, as shown in FIG. 9, in the current coupling metal fitting 10C, the bending moment also increases at the inner peripheral side portion on the Y1 side adjacent to the groove-shaped arm portion 30C in the bending beam portion 50C, and the inner periphery thereof. Since the second portion is deformed so that the radius of curvature of the portion on the side is increased and is also distorted vertically downward by a load, the second stress concentration portion 52C is concentrated. However, in the second stress concentration portion 52C, although the stress is smaller than that in the maximum stress concentration portion 51C, the stress is higher than that in portions other than the maximum stress concentration portion 51C.

On the other hand, the stress concentration of the coupling fitting 10 of the present embodiment is as shown in FIGS. FIG. 10 is a perspective view showing a state of stress concentration on the insertion arm portion 20 side in the coupling fitting 10 of the present embodiment. FIG. 11 is a perspective view showing a state of stress concentration on the grooved arm portion 30 side of the coupling fitting 10 of the present embodiment.

As shown in FIG. 10, also in the joint fitting 10 of the present embodiment, the portion on the inner peripheral side on the Y1 side adjacent to the insertion arm portion 20 in the bending beam portion 50 is the above-described maximum stress concentration portion 51C. Similarly, the maximum stress concentration portion 51 where the stress is most concentrated. However, when the same load as in FIG. 8 was applied, the stress at the maximum stress concentration portion 51 was 540 N / mm ² . Further, as shown in FIG. 11, stress is also concentrated on the inner peripheral side portion on the Y1 side adjacent to the arcuate projecting portion 40 in the bending beam portion 50 in the coupling member 10 of the present embodiment. Although the second stress concentration portion 52 is formed, the stress is much smaller in the second stress concentration portion 52 than in the maximum stress concentration portion 51.

As apparent from the comparison between FIG. 8 and FIG. 10, the length (span) of the bent beam portion 50 is shortened by the presence or absence of the arc-shaped protruding portion 40, and as a result, the stress at the maximum stress concentration portion 51 is reduced. ing. Moreover, since the stress is greatly reduced in the portion corresponding to the second stress concentration portion 52C due to the presence of the arcuate overhanging portion 40, the elongation and strain at the second stress concentration portion 52C are greatly reduced. .

Further, in the bending beam portion 50C, the distance from the load portion 53C to the end on the insertion arm portion 20C side and the distance from the load portion 53C to the end on the grooved arm portion 30C side are shown in FIG. 8 and FIG. However, in the present embodiment, since the arcuate projecting portion 40 exists, in the bending beam portion 50, the distance from the load portion 53 to the end portion on the insertion arm portion 20 side, and the load portion 53 of the load. 10 and FIG. 11, the distance from the load portion 53 to the load is not uniform.

And it is thought that the load in the beam edge part 54 by the side of the arcuate overhang | projection part 40 near the load part 53 of a load among the bending beam parts 50 is larger than the load in the edge part by the side of the insertion arm part 20 side. Therefore, between the end on the insertion arm portion 20C side of the bending beam portion 50C and the end portion on the insertion arm portion 20 side of the bending beam portion 50, the end portion on the insertion arm portion 20 side has a bending moment. It can be considered that the stress at the end on the side of the insertion arm 20 is reduced by a small amount.

<About effect>
According to the coupling fitting 10 having the above-described configuration, the bending beam portion 50 is provided with a circular cross section perpendicular to the extending direction over the entire extending direction. Further, an arc-like overhanging portion 40 for reducing the extension length of the bending beam portion 50 is provided between the bending beam portion 50 and the groove-shaped arm portion 30, and the width direction in the cross section of the arc-like overhanging portion 40 is provided. The thickness dimension in the thickness direction (Z direction) orthogonal to is set larger than the diameter of the cross section of the bent beam portion 50.

For this reason, since the cross section of the bending beam portion 50 is circular, the chain can freely rotate regardless of the position of the bending beam portion 50. Therefore, chain tangles can be prevented.

Further, the extension length (span) of the bent beam portion 50 can be shortened by the presence of the arcuate overhanging portion 40. For this reason, the cross section of the bending beam portion 50 is circular at any part, and the bending beam portion is reduced while reducing the cross-sectional area of the bending beam portion 50 on the grooved arm portion 30 side as compared with the current coupling fitting 10C. A sufficient strength of 50 can be secured. Thereby, the process for improving the strength of the bent beam portion 50 can be reduced.

Further, in the present embodiment, the inner peripheral portion of the arc-shaped projecting portion 40 constitutes a part of an arc-shaped locus that is continuous with the bent beam portion 50. For this reason, the surrounding hole S1 can be maintained at a constant diameter, and it is possible to pass a round bar having a large diameter or to hang a hook ring portion having a larger diameter than the chain. In addition, stress concentration can be prevented from occurring in the inner peripheral portion of the arc-shaped protruding portion 40.

Furthermore, in this Embodiment, the surface and back surface which are located in the both ends side of the thickness direction (Z direction) of the arc-shaped overhang | projection part 40 are the surfaces located in the both ends side of the thickness direction (Z direction) of the groove-shaped arm part 30 And provided flush with the back surface. For this reason, it can prevent that a level | step difference is formed between the groove-shaped arm part 30 and the arcuate overhang | projection part 40, and it becomes possible to prevent the damage | wound and damage resulting from presence of a level | step difference.

In the present embodiment, the connector 11 includes the through-hole 21 of the insertion arm portion 20 of one of the two fittings 10 and the groove-like arm portion 30 of the other fitting 10. The insertion holes 33a and 33b are aligned, and the

insertion holes

33a and 33b of the groove-shaped arm 30 of one of the two coupling fittings 10 and the insertion arm 20 of the other coupling fitting 10 are aligned. The through holes 21 are aligned. And in the alignment state, it has set it as the structure by which the two coupling metal fittings 10 were connected by the connection pin 100 being penetrated by the through-hole 21 and

insertion hole

33a, 33b. Therefore, by using the connector 11 of the present embodiment, one of the two coupling fittings 10 is connected to, for example, a chain, and the other member is easily connected to a hook or a hanging fitting. Can be easily realized.

<4. Modification>
As mentioned above, although each embodiment of this invention was described, this invention can be variously deformed besides this. This will be described below.

In the above-described embodiment, the arc-shaped projecting portion 40 is provided only on the groove-shaped arm portion 30 side. However, as long as the ring hole of the chain can be positioned in the bending beam portion 50, an arc-shaped protruding portion may be provided on the insertion arm portion 20 side. Moreover, it is good also as a structure which replaces the insertion arm part 20 and provides the arm part equivalent to the groove-shaped arm part 30 (that is, you may provide a pair of groove-shaped arm parts), and it replaces with the groove-shaped arm part 30 and inserts. It is good also as a structure which provides the arm part corresponded to the arm part 20 (namely, you may provide a pair of insertion arm part).

Further, in the above-described embodiment, the opposing

piece portions

31 a and 31 b of the groove-shaped arm portion 30 are provided so that the dimension in the thickness direction (Z direction) is larger than that of the insertion arm portion 20. However, the dimension in the thickness direction (Z direction) of the opposing

piece portions

31a and 31b may be equal to or less than the dimension in the thickness direction (Z direction) of the insertion arm portion 20.

Further, in the above-described embodiment, the connecting tool 11 is configured by connecting the pair of fittings 10. However, the coupler may be configured to combine the coupling fitting 10 with another coupling fitting.

DESCRIPTION OF

SYMBOLS

10,10C ... Coupling metal fitting, 11 ... Connector, 20,20C ... Inserting arm part, 21 ... Through hole, 22,23 ... Arc surface, 24 ... Inclined part, 30,30C ... Groove-shaped arm part, 31a, 31b ... opposing piece part, 32 ... groove part, 33a, 33b ... insertion hole, 34 ... arc surface, 40 ... arc-shaped overhang part, 40a ... end part, 50, 50C ... curved beam part, 51, 51C ... maximum stress concentration part, 52, 52C ... 2nd stress concentration part, 100 ... Connecting pin, 110 ... Spring collar, L1 ... Center line, S1 ... Go hole

Claims

A coupling fitting constituting a coupling tool by being coupled to another coupling bracket via a coupling pin,
An insertion arm having a through hole into which the connecting pin is inserted;
A groove-shaped arm portion located on the other end side facing the insertion arm portion located on one end side in the width direction, with an insertion hole into which the connecting pin is inserted,
A curved beam portion provided between the insertion arm portion and the groove-shaped arm portion;
With
The curved beam portion is provided with a circular cross section orthogonal to the extending direction over the entire extending direction,
Between the bent beam portion and the groove-shaped arm portion, an arcuate overhang portion for reducing the extension length of the bent beam portion is provided,
The thickness dimension in the thickness direction perpendicular to the width direction in the transverse cross section of the arcuate overhang portion is provided larger than the diameter of the cross section of the bent beam portion,
A coupling fitting characterized by that.
The coupling fitting according to claim 1,
The inner peripheral portion of the arc-shaped overhanging portion constitutes a part of an arc-shaped trajectory continuous with the bent beam portion.
A coupling fitting characterized by that.
The coupling fitting according to claim 1,
The front and back surfaces located on both end sides in the thickness direction of the arcuate overhang portion are provided flush with the front and back surfaces located on both end sides in the thickness direction of the groove-shaped arm portion.
A coupling fitting characterized by that.
The fitting according to claim 2,
The front and back surfaces located on both end sides in the thickness direction of the arcuate overhang portion are provided flush with the front and back surfaces located on both end sides in the thickness direction of the groove-shaped arm portion.
A coupling fitting characterized by that.
In order to connect a chain as an object to be connected, a connecting tool that is used as an annular shape by connecting two coupling fittings according to any one of claims 1 to 4,
The through hole of the insertion arm portion of one of the two coupling fittings and the insertion hole of the grooved arm portion of the other coupling fitting of the two coupling fittings are aligned. And
The insertion hole of the grooved arm portion of one of the two coupling fittings and the through hole of the insertion arm portion of the other coupling fitting of the two coupling fittings are positioned. Combined,
In the alignment state, the connecting pin is inserted into the through hole and the insertion hole, so that the two coupling fittings are connected.
A connector characterized by that.