Socket for channel material

Abstract

To provide a socket for channel materials with high fracture strength at the fastening portion. [Solution] The channel material socket 10 has a connecting portion 11 at one end that is connected to a rotary tool, a fastening portion 12 at the other end for fastening a screw, and a connecting portion 13 between the connecting portion 11 and the fastening portion 12. The outer circumference 12a of the fastening portion 12 is circular with an outer diameter smaller than the inner width of the channel material, and the inner circumference 12b of the fastening portion 12 is a regular hexagon. The connecting portion 13 is formed by a circular arc (with a radius of curvature of 1.0 mm or more) with a line constituting the inner circumference 12b of the fastening portion 12 as its tangent in a cross-section that includes the rotation axis direction of the fastening portion 12 and a direction perpendicular to the opposing sides of the inner circumference 12b.

Description

[Technical Field]

[0001] This invention relates to a socket for channel material. [Background technology]

[0002] When installing electrical conduits or PF pipes in the walls of buildings, channel members are typically used. Channel members are long members with a U-shaped cross-section. For example, when attaching electrical conduits to the walls of buildings, male threaded anchors are driven into the wall, the channel member is passed through the bolt portion of the protruding male threaded anchor, and secured with a nut. Further work is then done to secure the electrical conduits to the channel member using clips or similar devices.

[0003] Figure 5 shows the fastening process when attaching a channel member to a wall surface 700. As shown in Figure 5, the channel member 200 comprises an upper part 201, left and right side wall parts 202, left and right bottom parts 203, and left and right folded parts 204. As shown in Figure 5, the channel member 200 is attached to a bolt 300 protruding from the wall surface 700 by a washer 400 and a nut 500. The size of the nut used to attach the channel member 200 is usually 17HEX. For attaching the channel member 200 to the bolt 300, a channel member socket 600 is used, which has a connecting part at one end for connecting to a rotary tool and a fastening part at the other end for fastening a screw.

[0004] In this case, the external dimensions of the channel socket 600 are constrained by the depth D1 (distance between the upper part 201 and the folded portion 204) and the inner width W1 (distance between the folded portions 204) of the channel 200. As shown in Figure 5, in the channel socket 600, where the outer circumference of the fastening portion (socket portion) is a regular hexagon, there is an orientation in which the fastening portion has the shortest diameter (distance perpendicular to opposite sides of the regular hexagon) and an orientation in which the fastening portion has the longest diameter (distance parallel to opposite sides of the regular hexagon). The longest diameter is larger than the inner width W of the channel 200, and the shortest diameter is smaller than the inner width W1 of the channel 200.

[0005] Therefore, if the channel socket 600 is oriented to its shortest diameter, it can be inserted into the channel 200, and since the depth D1 of the channel 200 is sufficiently longer than the axial length D0 of the fastening portion, the installation of the channel 200 can be carried out without any problems.

[0006] However, as shown in Figure 6, thin channel members 200 also exist. In the case of the channel member socket 600 with the above configuration, it can be inserted into the channel member 200 if it is oriented in the direction of the shortest diameter, but since the depth D2 of the channel member is shorter than the axial length D0 of the fastening part, the installation work of the channel member 200 cannot be performed. However, there are constraints on the height of the nut 500, and it is not possible to shorten the axial length D0 of the fastening part of the channel member socket 600.

[0007] For example, if the socket has an outer circumference that is circular with an outer diameter smaller than the width W1 of the channel material 600, and an inner circumference that is a regular hexagon, it is possible to fasten thin channel materials. However, the thickness of the corners that form the vertices of the regular hexagon becomes thin, and the breaking strength of the fastened part decreases. Patent Document 1 discloses a technique to increase the strength by wrapping a reinforcing material containing a highly elastic fiber material around the fastened part. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2014-030855 [Overview of the project] [Problems that the invention aims to solve]

[0009] The wrench socket described in Patent Document 1 has the problem of requiring reinforcing materials, resulting in a large number of parts and increased manufacturing costs.

[0010] One of the objectives of this invention is to provide a socket for channel materials with high fracture strength at the fastening portion. [Means for solving the problem]

[0011] The inventors investigated the causes of the decrease in the breaking strength of the fastening portion and found that (1) the thickness of the inner circumferential shape of the fastening portion at the corners (i.e., the part corresponding to the corner of the nut) has a significant effect, and (2) the stress concentration that occurs at the boundary between the fastening portion and the connecting portion has a significant effect.

[0012] The inventors diligently conducted research to reduce the effects of the findings described in (2) above, and have completed the following socket for channel material.

[0013] A connecting portion is provided at one end for connection to a rotary tool, and a fastening portion is provided at the other end for fastening a screw, and a connecting portion is provided between the connecting portion and the fastening portion. The outer circumferential shape of the fastening portion is circular, having an outer diameter smaller than the inner width of the channel material. The inner circumference of the fastening portion is a regular hexagon. The connecting portion is formed by an arc tangent to a line constituting the inner circumference of the fastening portion in a cross-section that includes the rotation axis direction of the fastening portion and a direction perpendicular to the opposing sides of the inner circumference shape. A socket for channel material, wherein the radius of curvature of the aforementioned arc is 1.0 mm or more. [Effects of the Invention]

[0014] According to the present invention, a socket for channel materials with high fracture strength at the fastening portion can be obtained. [Brief explanation of the drawing]

[0015] [Figure 1] Figure 1 shows the configuration of a socket for channel material, where (a) is an external view and (b) is a cross-sectional view. [Figure 2] Figure 2 is a cross-sectional view perpendicular to the axis of rotation showing the configuration of the fastening part. [Figure 3] Figure 3 is a cross-sectional view perpendicular to the axis of rotation showing the configuration of the connecting part. [Figure 4] Figure 4 is a cross-sectional view perpendicular to the axis of rotation, showing other components of the connecting section. [Figure 5] FIG. 5 is a view showing the fastening operation when attaching the channel material to the bolt. [Figure 6] FIG. 6 is a view showing a thin channel material. [Figure 7] FIG. 7 is a view showing a socket for a channel material that adopts the normal inner peripheral shape of the socket. [Figure 8] FIG. 8 is a cross-sectional view showing the configuration of a normal socket.

Embodiments for Carrying Out the Invention

[0016] First, regarding the finding of (1) above, the case of attaching the channel material 200 to the bolt 300 with a 17 HEX nut will be described as an example.

[0017] According to the standard, the across-flat dimension of a 17 HEX nut is 16.3 - 17.0 mm. However, for example, in the case of a plated nut, due to the influence of plating thickness and plating accumulation, etc., the across-flat dimension may be about 17.2 mm. On the other hand, the across-corner dimension of a 17 HEX nut is about 19.6 mm. FIG. 7 is a view showing a socket for a channel material that adopts the normal inner peripheral shape of the socket. As shown in FIG. 7, the inner peripheral shape adopted in a normal socket has a suitable clearance with the nut to be fastened, and the distance S between the opposing sides of the fastening part corresponding to the across-flat of the nut i is set in the range of 17.2 - 17.4 mm. On the other hand, the distance D between the opposing corners of the fastening part i is about 19.9 mm. This is because in the design of a normal socket, it is to make it easier to insert the nut and to securely fasten the nut.

[0018] Here, in FIG. 7, a regular hexagon assumed based on the distance S between the opposing sides of the fastening part i is shown by a dashed line. However, if the inner peripheral shape adopted in a normal socket is directly adopted for the socket for the channel material, the distance D between the opposing corners of the fastening part iThis setting results in a wider gap than the spacing between the corners of the regular hexagon, and as a result, the thickness of the fastening becomes thinner at the opposing corners, reducing the breaking strength of the fastening.

[0019] Therefore, it is effective to increase the thickness at the opposing corners of the fastening portion, to the extent that it does not hinder the operability of the socket.

[0020] Next, we will explain the findings in (2) above.

[0021] Figure 8 is a cross-sectional view showing the configuration of a typical socket. As shown in Figure 8, a typical socket 100 includes a connecting portion 110 at one end that is connected to a rotary tool (not shown), a fastening portion 120 at the other end for fastening a screw (not shown), and a connecting portion 130 provided between the connecting portion 110 and the fastening portion 120. In some cases, another fastening portion (not shown) with a smaller diameter than the fastening portion 120 may be provided between the connecting portion 130 and the connecting portion 110. Such a socket is called a double socket, and the fastening portion 120 is sometimes called the outer socket, and the other fastening portion with a smaller diameter is sometimes called the inner socket.

[0022] In a typical socket 100, the connecting portion 130 is formed in a conical shape to connect the fastening portion 120 and the connecting portion 110 (or the inner socket in the case of a double socket). This serves as a stopper when a screw is inserted into the connecting portion 120, and as a guide to facilitate the introduction of a screw into the inner socket in the case of a double socket. On the other hand, a typical socket 100 is required to have a short axial length unless there are specific constraints, so the angle formed by the inner surface of the fastening portion 120 and the inner surface of the connecting portion 130 is steep. Depending on the machining precision, the boundary between the fastening portion 120 and the connecting portion 130 may be formed as a curved surface, but in order to shorten the axial length, its radius of curvature is extremely small, less than 0.5 mm.

[0023] While this is not a particular problem with standard sockets because the fastening portion has sufficient thickness, channel sockets have a thinner fastening portion than standard sockets. Therefore, if the same shape of the connecting portion used in standard sockets is applied, the breaking strength will decrease when torque is applied during fastening.

[0024] Therefore, it is effective to suppress stress concentration at the boundary between the fastening part and the connecting part, to the extent that it does not impede the operability of the socket.

[0025] Sockets for channel materials are used by connecting them to hand tools such as torque wrenches, or power tools such as impact wrenches and impact drivers. The following describes sockets for channel materials with reference to the drawings.

[0026] Figure 1 shows the configuration of a channel material socket, where (a) is an external view and (b) is a cross-sectional view. As shown in Figure 1, the channel material socket 10 has a connecting portion 11 at one end that is connected to a rotary tool (not shown) and a fastening portion 12 at the other end for fastening a screw (not shown). A connecting portion 13 is also provided between the connecting portion 11 and the fastening portion 12.

[0027] (Connection part 11) The connector 11 is used by connecting it to, for example, a hand tool such as a torque wrench, or a power tool such as an impact wrench or impact driver. When the channel material socket 10 is connected to a torque wrench, impact wrench, etc., the connector 11 has a hole shape corresponding to the socket's square drive (prism shape), and when it is intended to be connected to an impact driver, etc., it has a hole shape corresponding to a driver bit. When it is connected to a tool in other ways, it should have a hole shape corresponding to the connection method. Also, for example, the driver bit may be integrally molded with the socket, fixed by press-fitting into the connector 11, or connected to the connector 11 in a detachable manner. Furthermore, the connector 11 may be a shaft-shaped connector such as a hexagonal convex shape (bolt shape) that fits into a hand tool or other socket wrench. In the case of a driver bit integrally molded with the socket, it can also be called a shaft-shaped connector. The example shown in Figure 2 shows an example of a connector 11 intended for connection to a socket's square drive such as a torque wrench.

[0028] (Fastening part 12) The outer circumference 12a of the fastening portion 12 must be circular in shape, having an outer diameter smaller than the inner width (distance between folded portions 204) W1 of the channel material 200. A fastening portion 12 of this shape can be easily inserted into and removed from the gap of the folded portions 204 of the channel material 200, and the channel material 200 can be easily attached to the bolt 300. From the viewpoint of maintaining smooth rotation, the outer diameter of the outer circumference 12a of the fastening portion 12 should be as small as possible, for example, 20.2 mm or less, even 20.1 mm or less, and especially less than 20 mm.

[0029] Figure 2 is a cross-sectional view perpendicular to the axis of rotation showing the configuration of the fastening part. The connecting part 11 is not shown in Figure 2. The shape of the inner circumference 12b of the fastening part 12 is a regular hexagon and has a shape that satisfies the following conditions. A regular hexagon is not a perfect regular hexagon, and includes cases where the sides 12c are made up of straight lines but the corners 12d are made up of curves. In Figure 2, the distance S between opposing sides 12c of the fastening part 12. i The dashed lines represent the assumed regular hexagon based on [the given point].

[0030] When the shape of the inner periphery 12b of the fastening portion 12 has a distance S i (mm) between the opposing sides 12c of the shape of the inner periphery 12b and a distance D i (mm) between the opposing corners 12d in a cross section perpendicular to the rotation axis of the fastening portion 12, it satisfies Equation 1. [Equation 1

[0031] With such a configuration, the corners 12d of the inner periphery 12b of the fastening portion 12 are located inside a regular hexagon (broken line) assumed based on the distance S i between the opposing sides 12c of the fastening portion 12, and the wall thickness at the position of the opposing corners 12d of the fastening portion 12 can be increased. As a result, the fastening portion 12 can be provided with sufficient breaking strength.

[0032] The corners 12d of the fastening portion 12 are, for example, formed of a curved surface. In the cross section shown in FIG. 2, they appear as curves. Further, the corners 12d of the fastening portion 12 may be formed, for example, by an arc that is tangent to the straight line forming the side 12c. The radius of curvature of the arc in this case is, for example, 1.90 mm. Also, the corners 12d may be formed by an arc that bulges slightly more on the outer peripheral side than the straight line forming the side 12c. The radius of curvature of the arc in this case is, for example, 2.25 mm, and the radius of curvature can be made larger than when the corners 12d are formed by an arc that is tangent to the straight line forming the side 12c.

[0033] When the diameter of the shape of the outer periphery 12a of the fastening portion 12 is R o , it is preferable that (R o - D i ) / 2 is 0.2 mm or more. Thereby, breakage at the corners 12d can be suppressed, and the fastening portion 12 can be provided with sufficient breaking strength.

[0034] The distance S iIt is preferable that the thickness be between 17.0 and 17.4 mm. If it is less than 17.0 mm, it may be difficult to insert the screw, and if it exceeds 17.4 mm, it may be difficult to secure the wall thickness at the corner 12d.

[0035] (Connection part 13) Figure 3 is a cross-sectional view perpendicular to the rotation axis direction showing the configuration of the connecting portion. The connecting portion 13 is composed of an arc tangent to the line constituting the inner circumference 12b of the fastening portion 12 in a cross-section that includes the rotation axis direction of the fastening portion 12 (direction X in the figure) and the direction perpendicular to the opposing sides 12c of the inner circumference 12b shape (direction Y in the figure), and the radius of curvature R of the arc is 1.0 mm or more. A socket for channel material equipped with a connecting portion 13 with such a large radius of curvature R can suppress stress concentration that occurs at the boundary between the fastening portion 12 and the connecting portion 13 during fastening, thereby increasing the fracture strength of the fastening portion. From the viewpoint of stress concentration, it is preferable that the radius of curvature R be, for example, 1.5 mm or more. On the other hand, if the radius of curvature is too large, there is a risk of the screw getting caught in the connecting portion 13 when fastening. Also, it becomes difficult to increase the wall thickness, making it difficult to smoothly connect the inner surfaces of the connecting portion 12 and the connecting portion 11, which may conversely cause stress concentration. Therefore, the practical upper limit for the radius of curvature R is 7.0 mm.

[0036] Here, Figure 4 is a cross-sectional view perpendicular to the rotation axis direction showing other components of the connecting portion. The connecting portion 13 may be entirely composed of arcs, but as shown in Figure 4, it is sufficient that at least the portion near the boundary with the fastening portion 12 is composed of arcs. In Figure 4, the connecting portion 13 is composed of arcs in the portion continuing from the boundary with the fastening portion 12 (indicated by the symbol d), and the portion to its right is composed of straight lines. However, if the portion indicated by the symbol d is too narrow, it may be difficult to avoid stress concentration. Therefore, it is preferable that the spacing of the portion indicated by the symbol d (length in the rotation axis direction (X direction in the figure)) be 1.0 mm or more. The spacing L can be said to be the length in the rotation axis direction of the connecting portion 13, which is composed of arcs, in a cross-section that includes the rotation axis direction of the fastening portion 12 (X direction in the figure) and the direction perpendicular to the opposing sides 12c of the shape of the inner circumference 12b (Y direction in the figure).

[0037] Furthermore, in this cross-section, the total length of the connecting portion 13 in the rotation axis direction (X direction in the figure) (length indicated by the symbol L) is preferably 1.0 to 5.0 mm. This is to minimize the overall length of the socket for the channel material. [Industrial applicability]

[0038] According to the present invention, a socket for channel materials with high fracture strength at the fastening portion can be obtained. [Explanation of Symbols]

[0039] 10-channel socket 11 Connection part 12 Fastening part 12a outer circumference 12b Inner circumference 12c side 12d corner 13 Connecting part 100 Socket for channel material 110 Connection part 120 Fastening part 130 Connection section 200 channel material 201 Top 202 Side wall section 203 Bottom 204 Turning point 300 volts 400 washers 500 nuts Socket for 600 channel material 700 Wall surface

Claims

1. A connecting portion is provided at one end for connection to a rotary tool, and a fastening portion is provided at the other end for fastening a screw, and a connecting portion is provided between the connecting portion and the fastening portion. The outer circumferential shape of the fastening portion is circular, having an outer diameter smaller than the inner width of the channel material. The inner circumference of the fastening portion is a regular hexagon. The connecting portion is formed by an arc tangent to a line constituting the inner circumference of the fastening portion in a cross-section that includes the rotation axis direction of the fastening portion and a direction perpendicular to the opposing sides of the inner circumference shape. A socket for channel material, wherein the radius of curvature of the aforementioned arc is 1.0 mm or more.

2. The socket for channel material according to claim 1, wherein in the cross-section, the length of the connecting portion in the rotation axis direction of the fastening portion is 1.0 to 5.0 mm.

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