JP7202933B2 - Tightening torque control tool and combination of tightening torque control tool and fastener - Google Patents

Description

The present invention relates to a tightening torque control tool for tightening a fastener such as a nut or bolt to a required torque, and a combination of such a tightening torque control tool and the fastener.

2. Description of the Related Art As is well known, bolts and nuts are used in large numbers in the installation of noise barriers on highways, the installation of ceiling walls in tunnels and the like, and the installation of various parts in various structures. In such fastening, a nut (usually a locking nut) is attached to the bolt, for example, in the case of a hexagonal nut with a nominal diameter of M10, it is about 17 to 24 Nm, and in the case of a hexagonal nut with a nominal diameter of M24, it is 250 Nm. It is important to tighten with a relatively high required torque, which is in the order of .about.360 Nm. Patent Literature 1 listed below discloses a tightening torque control tool that can be used when tightening a nut to a bolt or a bolt to a nut with a required torque. Such a tightening torque management tool is integrally formed from synthetic resin and includes a fastener housing portion and a tightening torque applying portion. The fastener housing portion is formed with a housing hole whose lower end face is open, and the inner peripheral surface of this housing hole is part of the regular polygonal inner peripheral surface corresponding to the torque-applying regular polygonal outer peripheral surface of the fastener. It is a form in which a concave portion is formed. The outer peripheral surface of the tightening torque applying portion corresponds to the outer peripheral surface of the torque applying regular polygon of the fastener. A fastener is at least partially housed in the housing hole of the fastener housing section, and an appropriate automatic or manual tightener is engaged with the outer peripheral surface of the tightening torque application section to apply tightening torque, thereby tightening torque. Tightening torque is transmitted to the fastener through the additional portion and the fastener storage portion. When the torque applied to the fastener exceeds a predetermined threshold value, the inner peripheral surface of the receiving hole is deformed, causing the fastener receiving portion to idle with respect to the fastener.

JP 2018-8352 A

Therefore, in the conventional tightening torque control tool as described above, especially when the torque threshold to be managed is large, the thickness of each part of the torque applying part as well as the thickness of each part of the fastener storage part is set considerably large. It is therefore a problem that the production requires a large amount of material and increases production costs, and it is also relatively difficult to avoid the so-called sink marks that tend to occur during molding. However, there is a problem that the productivity is low because it takes a relatively long time for cooling.

As a tightening torque management tool that solves the above problem, the present inventors have previously proposed in Japanese Patent Application No. 2018-104334 that a fastener storage portion and a tightening torque applying portion are separately arranged. Instead, the present inventors have proposed a tightening torque management tool of a unique form in which the outer peripheral surface of the part itself defining the housing hole for housing the fastener is used as the tightening torque applying part. Such a tightening torque control tool is integrally formed from a synthetic resin, and has an inner peripheral surface that defines a storage hole with an open lower end face and an outer peripheral surface that is similar in shape to an outer peripheral surface of a torque-applying regular polygon of the tightening tool. The inner peripheral surface defining the storage hole has a shape in which a recess is partially formed in the regular polygonal inner peripheral surface corresponding to the torque-applying regular polygonal outer peripheral surface of the fastener, and the storage hole has at least When tightening torque is applied to the outer peripheral surface of the fastener with the fastener partially stored, if the tightening torque exceeds the threshold, the inner peripheral surface of the storage hole is partially deformed and rotates against the fastener. It is characterized by

However, according to the experience of the present inventors, the above-described tightening torque control tool proposed by the present inventors is still not sufficiently satisfactory, and the following problems should be solved. It turned out that the problem remained. Specifically, when the tightening torque to be applied to the tightening tool is particularly large, the socket of the automatic or manual tightening tool is fitted to the outer peripheral surface of the tightening torque control tool to apply the tightening torque to the tightening torque control tool. When the fastener is tightened by the fastener, not only the inner peripheral surface of the tightening torque control tool but also the outer peripheral surface are plastically deformed, and the outer peripheral surface spreads outward, which causes the fastener to bite into the inner peripheral surface of the socket. , it tends to be difficult to disengage the tightening torque manager from the socket of the fastener.

The present invention has been made in view of the above-mentioned facts, and its main technical problem is to fit a socket of an automatic or manual tightening tool to the outer peripheral surface of the tightening torque control tool so that the tightening torque control tool can be used. Even if the fastener is tightened by applying a large tightening torque, and the outer peripheral surface of the tightening torque control tool is also plastically deformed, the outer peripheral surface of the tightening torque control tool bites into the inner peripheral surface of the socket of the fastener. To provide a new and improved tightening torque management tool which avoids this.

As a result of extensive studies, the inventors of the present invention have found that the previously proposed tightening torque management tool should have a through opening penetrating from the bottom surface of the recess to the outer peripheral surface at a predetermined portion of the recess, or the inner circumference of the outer peripheral surface. It has been found that the above main technical problem can be achieved by forming recessed portions in regions corresponding to the recessed portions of the surface.

That is, according to the first aspect of the present invention, as a tightening torque control tool for achieving the main technical problem described above, the inner part is integrally formed from a synthetic resin and defines a storage hole with an open lower end face. It has a peripheral surface and an outer peripheral surface having a similar shape to the outer peripheral surface of the torque-applying regular polygon of the fastener, and the inner peripheral surface defining the storage hole is a regular polygon corresponding to the outer peripheral surface of the torque-applying regular polygon of the fastener. Each of the side surfaces of the inner peripheral surface of the square is partially formed with a concave portion, and a through opening is formed at a predetermined portion of the concave portion so as to penetrate from the bottom surface of the concave portion to the outer peripheral surface. When a fastener is at least partially received in the hole and tightening torque is applied to the outer circumferential surface, the inner circumferential surface of the receiving hole is partially deformed into the fastener when the tightening torque exceeds a threshold value. There is provided a tightening torque management tool characterized in that it is idly rotated against.

According to a second aspect of the present invention, a tightening torque control tool that achieves the above main technical problem is integrally formed from a synthetic resin and has an inner peripheral surface that defines a storage hole with an open lower end surface. and an outer peripheral surface having a similar shape to the torque-applying regular polygonal outer peripheral surface of the fastener, and the inner peripheral surface defining the storage hole is inside a regular polygon corresponding to the torque-applying regular polygonal outer peripheral surface of the fastener. Each of the side surfaces of the peripheral surface has a form in which recesses are partially formed, and recessed portions are formed in regions of the outer peripheral surface corresponding to the recesses of the inner peripheral surface, and at least in the storage hole. When a fastener is partially housed and a tightening torque is applied to the outer peripheral surface, when the tightening torque exceeds a threshold value, the inner peripheral surface of the storage hole is partially deformed and slips against the fastener. Provided is a tightening torque management tool characterized by:

Preferably, each of said side faces of said receiving hole is angularly aligned with each of said side faces of said outer peripheral surface. Preferably, the through opening is formed at least axially below the recess, or the recessed portion is formed in a region of the outer peripheral surface corresponding to at least the axially below the recess. Preferably, the through opening or recess is rectangular. In a typical form, the torque-applying regular polygonal peripheral surface of the fastener is a regular hexagon. Advantageously, the upper end of the inner peripheral surface is formed with a plurality of circumferentially spaced arcuate ridges extending in the circumferential direction. Preferably, an outer flange portion extending radially outward is formed at the lower end portion of the outer peripheral surface. The bottom surface of the recess preferably forms an obtuse angle with the upstream surface positioned upstream with respect to the tightening rotation, the upstream surface of the recess sloping outwardly in the direction of the tightening rotation. It is convenient to have Preferably, a holding protrusion is formed in a portion of each of the side surfaces of the housing hole located upstream of the recess when viewed in the tightening rotation direction.

The present invention further provides a combination of a tightening torque management tool as described above and a fastener at least partially received in the receiving hole of the tightening torque management tool. Preferably, the fastener is press fit into the receiving hole. In a typical form, the fastener is a hex nut.

In the tightening torque control tool of the present invention, the fastener is tightened by fitting the socket of the automatic or manual tightening tool to the outer peripheral surface of the tightening torque control tool and applying tightening torque to the tightening torque control tool. At that time, the plastic deformation generated on the outer peripheral surface of the tightening torque control tool is mainly generated in the through opening or the recessed part, and as a result, the outer peripheral surface of the tightening torque control tool bites into the inner peripheral surface of the socket of the fastener. Sticking is effectively avoided.

1 is a top perspective view of a preferred embodiment of a tightening torque management tool constructed in accordance with the present invention; FIG. FIG. 2 is an oblique view of the tightening torque management tool shown in FIG. 1 as seen from below; FIG. 2 is a front view partially showing a cross section of the tightening torque management tool shown in FIG. 1; FIG. 2 is a plan view of the tightening torque management tool shown in FIG. 1; FIG. 2 is a bottom view of the tightening torque management tool shown in FIG. 1; FIG. 2 is a front view partially showing a cross section of a combination of the tightening torque management tool shown in FIG. 1 and a nut, which is a typical example of a fastener; FIG. 7 is a bottom view of the combination shown in FIG. 6; FIG. 7 is a bottom view showing a state after the tightening torque of the nut exceeds the threshold value and the tightening torque management tool idles with respect to the nut in the combination shown in FIG. 6 ; FIG. 7 is a front view showing a state after the tightening torque of the nut exceeds the threshold value and the tightening torque management tool idles with respect to the nut in the combination shown in FIG. 6 ; FIG. 4 is a top perspective view of another preferred embodiment of a tightening torque management tool constructed in accordance with the present invention; FIG. 11 is a front view partially showing a cross section of the tightening torque management tool shown in FIG. 10; FIG. 11 is a plan view of the tightening torque management tool shown in FIG. 10; FIG. 11 is a bottom view of the tightening torque management tool shown in FIG. 10; A nut, which is a typical example of a fastener, is combined with the tightening torque shown in FIG. is a front view showing a state after has idled.

A further detailed description will be made below with reference to the accompanying drawings showing a preferred embodiment of a tightening torque management device constructed in accordance with the present invention and a combination of such an embodiment with a nut, which is a typical example of a fastener.

1 to 3, the tightening torque control tool, generally indicated by number 2, is made of a suitable synthetic resin, preferably a relatively high-strength synthetic resin such as polycarbonate or acrylonitrile butadiene styrene (ABS); It is integrally formed by injection molding or compression molding. The tightening torque control tool 2 has a cylindrical shape as a whole, and has an outer peripheral surface similar in shape to the inner peripheral surface 6 defining the storage hole 4 with the lower end face open and the outer peripheral surface of the torque-applying regular polygon of the tightening tool. 8.

4 and 5 together with FIGS. 1 to 3, the inner peripheral surface 6 defining the storage hole 4 is a virtual regular polygonal surface corresponding to the outer peripheral surface of a torque-applying regular polygon of the fastener to be stored. It is important to have a form in which recesses 12 are partially formed on each side surface 10 of the square inner peripheral surface. In the illustrated embodiment, the fastener is a hexagonal nut, as will be described later, so that the torque-applying regular polygonal outer peripheral surface of the fastener is a regular hexagon, and the imaginary regular polygonal inner peripheral surface (indicated by a two-dot chain line in FIG. 5) inner peripheral surface shown) is also a regular hexagon. Each of the recesses 12 formed in the center of each side face 10 is positioned on the upstream side as viewed in both side faces, that is, in the tightening rotation direction (clockwise in FIG. 4 and counterclockwise in FIG. 5) together with the bottom face 12a. It has an upstream face 12b and a downstream face 12c. The angle α formed by the bottom surface 12a and the upstream surface 12b is preferably an obtuse angle, particularly preferably about 100 to 160 degrees. In the illustrated embodiment, the bottom surface 12a has an arc shape forming a part of a circle centered on the center of the housing hole 4, and the upstream surface 12b extends outwardly with respect to the side surface 10 in the tightening rotation direction. extends at an angle to the It is preferable that the bottom surface 12a and the upstream surface 12b are smoothly connected via an arcuate boundary surface 12d. On the other hand, the downstream surface 12 c extends perpendicularly to the side surface 10 . It is convenient that the circumferential length L1 of the side surface 10a on the downstream side of the recess 12 in the tightening rotation direction is longer than the circumferential length L2 of the side surface 10b on the upstream side of the recess 12 (see below). As is clearly understood from the description, the tightening torque threshold is defined by the deformation of the side surface 10a on the downstream side of the recess 12).

A portion 10b located upstream of the recess 12 when viewed in the tightening rotation direction (clockwise direction in FIG. 4, counterclockwise direction in FIG. 5) on the side surface 10 defining the inner peripheral surface of the storage hole 4. is preferably provided with a retaining projection. In the illustrated embodiment, the retaining projection extends in the axial direction of the receiving hole 4 (vertically in FIG. 3 and perpendicular to the page in FIG. 5), preferably substantially parallel to the axis of the receiving hole 4. A rib 14 is formed. In the illustrated embodiment, a retaining projection or rib 14 is formed on each of the six side face 10 portions 10b. 2 and 3, each of the ribs 14 extends substantially parallel to the axis of the storage hole 4 from the upper end of the storage hole 4 to the vicinity of the lower end thereof. It is preferable that the protrusion height H of the rib 14 is about 0.1 to 0.5 mm, and the circumferential width W of each rib 14 is about 0.1 to 0.5 mm. Advantageously, the cross-sectional shape of the protruding end of rib 14 is semi-circular as shown in FIG. In the illustrated embodiment, ribs 14 are formed on all six sides 10b of portions 10b, but if desired, three sides 10, for example every other side, or diametrically opposed ribs 14 may be provided. It is also possible to form the ribs 14 only on the two side surfaces 10 that are aligned with each other. Alternatively, a plurality of axially spaced or circumferentially spaced ribs may be formed on each of the side surfaces 10 .

The ribs 14 forming the holding protrusions are located not only on the portion 10b located on the upstream side of the recessed portion 12 when viewed in the tightening rotation direction on the side surface 10, but also on the downstream side of the recessed portion 12 when viewed on the side surface 10 in the tightening rotation direction. It can also be formed on the side portion 10a. However, if the portion 10a located on the downstream side of the recessed portion 12 as seen in the tightening rotation direction on the side surface 10 is also formed, the tightening rotation on the side surface 10 will occur when the tightening torque reaches a threshold value as will be described later. Since the portion 10a located on the downstream side of the recess 12 when viewed in the direction is mainly deformed, the rib 14 is deformed over its entirety prior to the deformation of the side surface 10, which causes the tightening torque to reach the threshold value. There is a tendency for the tightening torque management tool 2 to disengage from the fastener before reaching . Therefore, it is desirable that the rib 14 is not provided on the portion 10a of the side surface 10 located downstream of the recess 12 when viewed in the tightening rotation direction.

In the illustrated embodiment, an annular inner flange portion 16 extending radially inward is formed at the upper end portion of the tightening torque management tool 2 . The inner peripheral surface of the inner flange portion 16 is cylindrical, and a circular through hole 18 is defined by the inner peripheral surface of the inner flange portion 16 at the upper end of the tightening torque control tool 2 . The inner diameter of the inner flange portion 16 is smaller than the inner diameter of the receiving hole 4 so that a downward facing annular shoulder 20 is defined in the boundary region between the receiving hole 4 and the inner flange 16 . A plurality of arcuate ridges 22 are formed on the outer peripheral edge of the annular shoulder surface 20 at regular intervals in the circumferential direction. In the illustrated embodiment, six arcuate ridges 22 are formed corresponding to each of the corners defined between adjacent side faces 10 . On the other hand, an annular outer flange portion 24 extending radially outward is formed at the lower end portion of the tightening torque control tool 2 . The outer peripheral surface of the outer flange 24 is cylindrical. The upper surface of the tightening torque management tool 2 (including the upper surface of the inner flange portion 20) may be a substantially horizontal plane, and similarly the lower surface of the tightening torque management tool 2 (including the lower surface of the outer flange portion 24) A horizontal plane is fine. Chamfering is applied to the lower end of the inner peripheral surface of the storage hole 4 .

Continuing the description with reference to FIGS. 1 to 5, the outer peripheral surface 8 is similar in shape to the torque-applying square outer peripheral surface of the fastener as described above. In the illustrated embodiment, the fastener is a hexagonal nut, as will be described later, so that the outer peripheral surface 8 is a regular hexagon, the size of which is 1.2 to 1.6 times the torque-applying regular polygon of the fastener. A degree is convenient. Advantageously, each of the side surfaces 10 of the receiving hole 4 and each of the side surfaces 25 of the outer peripheral surface 8 are angularly aligned. As will be described later, when the torque applied to the outer peripheral surface 8 exceeds the threshold value while the fastener is stored in the storage hole 4, the inner peripheral surface 6 defining the storage hole 4 is deformed. In order to reliably avoid the formation of cracks across the surface 8 and the entire torque management device 2 being damaged, the diametrically opposite corners of the inner peripheral surface 6 (side surface 10 and side surface 10 The length X1 (FIG. 5) between the tolerance points is preferably smaller than the length X2 (FIG. 4) between the diametrically opposed side surfaces 25 of the outer peripheral surface 8 .

In the tightening torque management tool 2 configured according to the present invention, a through opening 26 is formed penetrating from the bottom surface 12a of the recess 12 disposed at the center of each side surface 10 to the outer peripheral surface 8. is important. The through-opening 26 is formed in a substantially central portion in the circumferential direction of the bottom surface 12a of the recess 12, and has a rectangular shape elongated in the axial direction from the lower end to the upper end of the recess 12. As shown in FIG. The through opening 26 does not necessarily need to extend from the lower end to the upper end of the recess 12, and may be formed in a part of the recess 12 in the axial direction. Since there is a tendency for plastic deformation to occur in the axially lower portion of the recess 12 in actual use, it is preferred that the through opening 26 is formed at least axially below the recess 12 . If desired, instead of the rectangular through-opening 26, an appropriately-shaped through-opening such as a triangular or trapezoidal shape whose circumferential width gradually decreases upward in the axial direction can be formed.

6 and 7 (in FIG. 7, a fastener, ie, a hexagonal nut 28 is press-fitted into the housing hole 4 to Although the ribs 14 are somewhat elastically or plastically deformed, such deformation is not shown and the ribs 14 are shown undeformed over the hex nut 28). It is convenient to circulate in In the embodiment shown in FIGS. 6 and 7, a lock hex nut 28 is shown as a typical fastener. The outer peripheral surface 30 of the hexagonal nut 28 is a regular hexagon, which is slightly larger than the imaginary regular hexagon of the storage hole 4 formed in the tightening torque fastener 2 if the manufacturing error of the hexagonal nut 28 is sufficiently small. (In other words, the imaginary regular hexagon of the storage hole 4 in the tightening torque management tool 2 is set smaller than the regular hexagon outer peripheral surface 30 of the hexagonal nut 28). Then, the main portion of the hexagonal nut 28 , that is, the portion other than the lower end portion is press-fitted into the housing hole 8 . An annular portion 32 formed on the upper surface of the hexagonal nut 26 is housed in a space defined by the radial tip surfaces of the plurality of arcuate ridges 22, and its upper edge abuts against the shoulder surface 20. be. The hexagonal nut 28 has a portion 10a located on the downstream side of the recess 12 as viewed in the tightening rotation direction (clockwise direction in FIG. 4 and counterclockwise direction in FIG. 5), and the rib 14 is formed on the outer peripheral surface of the hexagonal nut 28. It is held in the receiving hole 4 by pressing against 30 . The manufacturing tolerance of the tightening torque control tool 2, which is injection molded or compression molded from an appropriate synthetic resin, is relatively small, and therefore the manufacturing error of the inner peripheral surface of the housing hole 4 is relatively small. The manufacturing tolerance of the hexagonal nut 28 is relatively large, and therefore the manufacturing error of the outer peripheral surface 30 of the hexagonal nut 28 is relatively large. This is compensated for by elastic or plastic deformation of ribs 14 formed on the required portion of the inner peripheral surface of the housing hole 4 . Therefore, excessive or insufficient force required for press-fitting the hexagonal bolt 28 into the housing hole 4 is avoided as much as possible.

To explain how to use the tightening torque management tool 2 as described above, when the hexagonal nut 28 is already combined with the tightening torque management tool 2, the shaft portion 34 of the bolt to which the hexagonal nut 28 is to be fastened (FIG. 6) (If the tightening torque control tool 2 is not combined with the hexagon nut 28, the hexagon nut 28 temporarily tightened to the bolt is stored in the storage hole 4 of the tightening torque control tool 2. ). Next, as indicated by the two-dot chain line in FIG. 6, the socket 36 of the automatic or manual tightening tool (the inner peripheral surface of the socket 36 has a hexagonal cylindrical shape corresponding to the outer peripheral surface of the tightening torque control tool 2) is tightened. It fits on the outer peripheral surface 8 of the torque control tool 2 . At this time, by bringing the lower end of the socket 36 into contact with the upper surface of the outer flange portion 24 of the tightening torque management tool 2, the socket 36 can be sufficiently easily positioned with respect to the tightening torque management tool 2 as required. be able to. Thereafter, the socket 36 of the fastener is rotated in the fastening direction (clockwise in FIG. 4 and counterclockwise in FIG. 5). The torque applied from the socket 36 to the tightening torque management tool 2 is transmitted to the hexagonal nut 28, thereby tightening the hexagonal nut 28 onto the shaft portion 34 of the bolt. When the hexagonal nut 28 advances over a relatively long distance in the axial direction with respect to the bolt shank 34, the bolt shank 34 is tightened as shown by the two-dot chain line in FIG. It moves upward through a through hole 18 defined by the inner flange portion 16 of the torque management tool 2 .

When the tightening torque transmitted to the hexagonal nut 28 exceeds a predetermined threshold value, as shown in FIG. is a portion downstream of the recess 12 of the upstream side surface 10 from the boundary area between the upstream side surface 10 and the downstream side surface 10 when viewed in the tightening rotation direction) is opposite to the tightening rotation direction The hexagonal nut 28 is pushed sideways and deformed, causing the tightening torque control tool 2 to idle against the hexagonal nut 28, thus tightening the hexagonal nut 28 to the bolt with the required tightening torque. When the tightening torque control tool 2 begins to idle with respect to the hexagonal nut 28, the corners of the outer peripheral surface of the hexagonal nut 26 may violently collide with the upstream surface 12b of the concave portion 12 of the housing hole 4. In this embodiment, since the bottom surface 12a and the upstream surface 12b of the recess 12 form an obtuse angle, the force applied from the corners of the outer peripheral surface of the hexagonal nut 28 to the upstream surface 12b of the recess 12 is appropriately damped or eliminated. be. In addition, the socket 36 fitted on the outer peripheral surface 8 of the tightening torque management tool 2 functions as a reinforcing material member for the tightening torque management tool 2 . Thus, generation of cracks in the tightening torque management tool 2 or breakage of the tightening torque management tool 2 is avoided as much as possible. When the inner peripheral surface 6 of the housing hole 4 of the tightening torque management tool 2 is deformed as described above, the outer peripheral surface 8 is also deformed. In the tightening torque management tool 2 configured according to the present invention, the torque is generated intensively at the portion where the through opening 26 is formed, and as shown in FIG. The defining portion is deformed toward the opposite side of the tightening rotation direction to reduce the width of the through opening 26 . According to the experience of the inventors, the reduction in the width of the through opening 26 occurs mainly in the axial lower portion of the through opening 26, in other words, the deformation of the outer peripheral surface 8 mainly corresponds to the axial lower portion of the through opening 26. Occur. Therefore, the through opening 26 is preferably formed at least axially below the recess 12 . In the tightening torque management tool 2 constructed in accordance with the present invention, the tendency of the outer peripheral surface 8 to widen outward in the radial direction is due to the existence of the through openings 26, and the outer peripheral surface 8 is deformed in the circumferential direction. Since the deformation of the outer peripheral surface 8 is concentrated at the portion where the through opening 26 is formed, the outer peripheral surface 8 will bite into the inner peripheral surface of the socket 36 of the fastener. is avoided as much as possible. Therefore, after the tightening torque control tool 2 begins to idle with respect to the hexagonal nut 28, the bolt shaft 34 is tightened with the required tightening torque, and the tightening torque control tool 2 can be easily removed from the hexagonal nut 28. can leave.

10-12 illustrate another preferred embodiment of a tightening torque management device constructed in accordance with the present invention. In the tightening torque management tool 102 illustrated in FIGS. 10 to 12, instead of the through opening 26 in the above-described tightening torque management tool 2, an area corresponding to the recess 112 in the outer peripheral surface 108 (that is, the above-described tightening A recessed portion 126 is formed in the portion of the torque management tool 2 where the through opening 26 is formed to locally reduce the wall thickness. As in the case of the through opening 26 in the tightening torque management tool 2 described above, the recessed portion 126 is positioned approximately in the circumferential center of the bottom surface 112a of the corresponding recessed portion 112, and is elongated in the axial direction from the lower end to the upper end of the recessed portion 112. It has an elongated rectangular shape. The recessed portion 126 does not necessarily need to extend from the lower end to the upper end of the recessed portion 112, and may be formed corresponding to a part of the recessed portion 112 in the axial direction. Since there is a tendency for plastic deformation to be generated corresponding to the axially lower portion of the recess 112 when used in . If desired, instead of the rectangular recessed portion 126, an appropriately shaped recessed portion, such as a triangular or trapezoidal shape, whose circumferential width gradually decreases upward in the axial direction, can be formed. The configuration of the tightening torque management tool 102 shown in FIGS. 10 to 12 is substantially the same as that of the tightening torque management tool 2 described above, except for the above-described configuration (that is, the recessed portion 126).

In the tightening torque management tool 102 shown in FIGS. 10 to 12 as well, when the tightening torque management tool 102 is used and the inner peripheral surface 106 of the housing hole 104 of the tightening torque management tool 102 is deformed, The outer peripheral surface 108 is also deformed, but the deformation of the outer peripheral surface 108 is concentrated in the portion where the deformation resistance is small, that is, the portion where the recessed portion 126 is formed. The portion defining the downstream side when viewed in the direction of rotation is deformed toward the side opposite to the direction of rotation to reduce the width of the recessed portion 126 . The reduction in the width of the recessed portion 126 occurs mainly in the axially lower portion of the recessed portion 126 , in other words, the deformation in the outer peripheral surface 108 occurs mainly corresponding to the axially lower portion of the recessed portion 126 . Therefore, it is preferable that the recessed portion 126 is formed in a region corresponding to at least the axially downward portion of the recessed portion 112 . In the tightening torque management tool 102 configured in accordance with the present invention, the tendency of the outer peripheral surface 108 to widen radially outward is due to the presence of the recessed portion 126, which causes the outer peripheral surface 108 to deform in the circumferential direction. Since the deformation of the outer peripheral surface 108 is concentrated at the portion where the recessed portion 126 is formed, the outer peripheral surface 108 is deformed against the inner peripheral surface of the socket 36 (FIG. 6) of the fastener. is avoided as much as possible. Therefore, after the tightening torque control tool 102 begins to idle against the hexagonal nut 28 (FIG. 6), the hexagonal nut 28 (FIG. 6) is tightened with the required tightening torque on the shaft portion 34 (FIG. 6) of the bolt. ), the tightening torque management tool 102 can be removed easily enough.

2: Tightening torque control tool 4: Storage hole 6: Inner peripheral surface 8: Outer peripheral surface 10: Side surface of inner peripheral surface 12: Recess 12a: Bottom surface of recess 12b: Upstream surface of recess 12c: Downstream surface of recess 14: Ribs (holding protrusions)
16: Inner flange portion 24: Outer flange portion 25: Side surface of outer peripheral surface 26: Through opening 28: Hexagonal nut 34: Bolt shaft portion 36: Socket of fastener 102: Tightening torque control tool 104: Storage hole 106 : inner peripheral surface 108: outer peripheral surface 126: immersion portion

Claims (14)

It is integrally formed of synthetic resin and has an inner peripheral surface that defines a storage hole with an open lower end surface and an outer peripheral surface that is similar in shape to the torque-applying regular polygonal outer peripheral surface of the fastener, and the storage hole The inner peripheral surface that defines the is a form in which a recess is partially formed on each of the side surfaces of the regular polygonal inner peripheral surface corresponding to the torque-applying regular polygonal outer peripheral surface of the fastener, and further at a predetermined portion of the recess is formed with a through opening that penetrates from the bottom surface of the recess to the outer peripheral surface, and when a fastener is at least partially housed in the storage hole and tightening torque is applied to the outer peripheral surface, the tightening torque is A tightening torque management tool characterized in that, when a threshold value is exceeded, the inner peripheral surface of the housing hole is partially deformed and comes to idle with respect to the fastener. It is integrally formed of synthetic resin and has an inner peripheral surface that defines a storage hole with an open lower end surface and an outer peripheral surface that is similar in shape to the torque-applying regular polygonal outer peripheral surface of the fastener, and the storage hole The inner peripheral surface defining the is a form in which recesses are partially formed on each of the side surfaces of the regular polygonal inner peripheral surface corresponding to the torque-applying regular polygonal outer peripheral surface of the fastener, and further the inner peripheral surface on the outer peripheral surface A recessed portion is formed in a region of the peripheral surface corresponding to the recess, and when a fastener is at least partially stored in the storage hole and a tightening torque is applied to the outer peripheral surface, the tightening torque reaches a threshold value. above, the inner peripheral surface of the housing hole is partially deformed and idly rotates with respect to the fastener. 3. The tightening torque management tool according to claim 1, wherein each of said side faces of said receiving hole is angularly aligned with each of said side faces of said outer peripheral surface. 4. The tightening torque management according to claim 3, wherein the through opening is formed at least axially below the recess , or the recessed portion is formed in a region of the outer peripheral surface corresponding to at least the axially below the recess. equipment. 5. A tightening torque management tool according to any one of claims 3 to 4, wherein the through opening or recess is rectangular. 6. The tightening torque management tool according to any one of claims 1 to 5, wherein the torque-applying regular polygonal outer peripheral surface of the fastener is a regular hexagon. 7. The tightening torque management tool according to any one of claims 1 to 6, wherein a plurality of arc-shaped ridges extending in the circumferential direction are formed at intervals in the circumferential direction on the upper end of the inner peripheral surface. 8. The tightening torque management tool according to any one of claims 1 to 7, wherein an outer flange portion extending radially outward is formed at the lower end portion of the outer peripheral surface. 9. The tightening torque management tool according to any one of claims 1 to 8, wherein the bottom surface of the recess and the upstream surface located upstream in the tightening rotation form an obtuse angle. 10. The tightening torque management tool of claim 9, wherein the upstream surface of the recess slopes outwardly in the tightening rotational direction. 11. The fastener according to any one of claims 1 to 10, wherein a retaining projection is formed on a portion of each of said side faces of said receiving hole located upstream of said recess when viewed in the direction of fastening rotation. With torque control tool. 12. A combination of a tightening torque management device according to any one of claims 1 to 11 and a fastener at least partially received in said receiving hole of said tightening torque management device. 13. The combination of claim 12, wherein said fastener is press fit into said receiving hole. 14. A combination as claimed in claim 12 or 13, wherein the fastener is a hex nut.

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