JP6892802B2 - Tightening torque control tool and combination of tightening torque control tool and fastener - Google Patents

Description

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

For example, in the installation of sound insulation walls on highways, the installation of ceiling walls such as tunnels, or the installation of various parts in various buildings, as is well known, many fastenings of bolts and nuts are used. In such fastening, it is important to tighten the nut (usually a locking nut) to the bolt with a relatively large required torque of, for example, about 17 to 24 Nm in the case of a hexagon nut having a nominal diameter of M10. Is. The following Patent Documents 1 and 2 disclose a tightening torque management 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 includes a fastener accommodating portion and a tightening torque adding portion that are integrally connected by a connecting portion that is broken by a required torque. The nut or the head of the bolt is housed in the fastener storage part, and torque is applied to the tightening torque addition part to tighten the nut to the bolt or the bolt to the nut. When the tightening torque applied to the nut or bolt via the fastener storage portion added to the tightening torque addition portion exceeds the threshold value, the connection portion is broken and the tightening torque addition portion is separated from the fastener storage portion. Thus, the nut is tightened to the bolt or the bolt is tightened to the nut with the required torque.

JP 2001-140832 JP 2015-224781

Therefore, the tightening torque control tool disclosed in Patent Documents 1 and 2 needs to be entirely made of a tough metal such as iron, especially when a relatively large tightening torque is required. Therefore, there is a problem to be solved that the manufacturing cost is high. When formed from an appropriate synthetic resin in order to reduce the manufacturing cost, the connection part connecting the fastener storage part and the tightening torque addition part is at a time when the tightening torque applied to the tightening torque addition part is small. It will be broken.

In order to solve the above-mentioned problems in the tightening torque control tool disclosed in Patent Documents 1 and 2, the present inventors have previously described the conventional form in the specification of Japanese Patent Application No. 2016-139152. Proposed a completely different and unique form of tightening torque control tool. Such a tightening torque management tool includes a fastener accommodating portion and a tightening torque adding portion integrally formed of synthetic resin. The fastener storage portion is formed with a storage hole having an open free end, and this storage hole is intermediate between each side surface of the regular polygon inner peripheral surface corresponding to the torque-applied regular polygon outer peripheral surface of the fastener. It is a form in which a recess is formed in the portion. When the tightening torque added to the tightening torque addition part and transmitted to the fastener through the fastener storage part exceeds the threshold value, the inner peripheral surface of the storage hole is deformed and the fastener storage part is deformed with respect to the fastener. It will spin idle and thus the tightening torque of the fasteners will be managed.

Even if the tightening torque control tool as described above proposed by the present inventors is formed of an appropriate synthetic resin such as polycarbonate and acrylonitrile-butadiene styrene, the tightening torque at which the inner peripheral surface of the storage hole is deformed is started. Can be set to a sufficiently high value, and therefore the manufacturing cost can be reduced by forming from an appropriate synthetic resin.

However, according to the experience of the present inventors, it has been found that the tightening torque management tool as described above proposed by the present inventors is not yet sufficiently satisfactory and has the following problems. did. That is, the tightening torque control tool made of synthetic resin can be molded with sufficient precision by injection molding or compression molding, and the manufacturing tolerance can be sufficiently reduced. On the other hand, as is well known to those skilled in the art, the manufacturing tolerances of ordinary fasteners that are widely sold, that is, ordinary nuts or bolts, are relatively large. Therefore, especially when the head of the nut or bolt is press-fitted into the storage hole formed in the fastener storage portion of the tightening torque control tool and the tightening torque control tool and the fastener are combined and provided to the market (1). ) If the head of the nut or bolt is excessively large with respect to the storage hole, a large force is required when the head of the nut or bolt is press-fitted into the storage hole, and a large stress is generated in the fastener storage portion, which is caused by this. Then, when the nut or bolt is actually tightened to the bolt or nut, the fastener storage portion of the tightening torque control tool tends to be broken. (2) On the other hand, the nut or bolt head is attached to the storage hole. If it is excessively small, the head of the nut or bolt is stored in the storage hole by a minute force, but there is a considerable possibility that the head of the nut or bolt will fall out of the storage hole due to vibration during transportation or the like.

The present invention has been made in view of the above facts, and the main technical problem thereof is to compare the fasteners by further improving the tightening torque management tool as described above proposed by the present inventors. New and improved tightening that prevents the force required to store the fastener in the storage hole of the fastener storage from becoming excessive or excessive due to a large manufacturing tolerance as much as possible. To provide a torque control tool with attachment, and also to provide a new and improved combination of such tightening torque control tool and fastener.

As a result of diligent studies and experiments, the present inventors have conducted an upstream of the recess in the tightening rotation direction on the side surface of the regular polygon inner peripheral surface corresponding to the regular polygon inner peripheral surface defining the storage hole. It has been found that the above-mentioned main technical problem can be achieved by disposing the holding protrusion in the portion located on the side.

That is, according to one aspect of the present invention, the tightening torque management tool that achieves the above-mentioned main technical problem includes a fastener storage portion and a tightening torque addition portion integrally formed of synthetic resin.
A storage hole having a free end opened is formed in the fastener storage portion, and the inner peripheral surface of the storage hole is each of the regular polygon inner peripheral surfaces corresponding to the torque-applied regular polygon outer peripheral surface of the fastener. It is a form in which a recess is formed in the middle part of the side surface.
A holding protrusion is provided on a portion of the side surface of the inner peripheral surface of the regular polygon located on the upstream side of the recess when viewed in the tightening rotation direction.
When the tightening torque applied to the tightening torque adding portion and transmitted to the fastener through the fastener storage portion exceeds the threshold value, the inner peripheral surface of the storage hole is deformed and the fastener is fastened to the fastener. The tool compartment now spins, thus managing the tightening torque of the fasteners.
A tightening torque control tool is provided.

Preferably, the holding protrusion is a rib extending in the axial direction of the storage hole. The protruding height of the rib is preferably 0.1 to 0.5 mm, and the circumferential width of the rib is preferably 0.1 to 0.5 mm. Preferably, the cross-sectional shape of the protruding end of the rib is a semicircular shape. The outer peripheral surface of the torque-applied regular polygon is a regular hexagon, and it is desirable that the holding protrusion is arranged at a portion located on the upstream side of the recess on each of the six side surfaces. It is convenient that the outer peripheral surface of the tightening torque adding portion is a regular polygon corresponding to the torque applying regular polygon outer peripheral surface of the fastener.

According to another aspect of the present invention, the tightening torque control tool and the tightening tool provided by the first aspect of the present invention as a combination of the tightening torque control tool and the fastener which solves the above-mentioned main technical problem. A combination with a fastener that is at least partially housed in the storage hole of the torque control tool is provided.

It is preferable that the fastener is press-fitted into the storage hole. The fastener may be a hexagon nut.

In the tightening torque control tool and the combination of the tightening torque control tool and the fastener of the present invention, the tightening torque control tool is made of synthetic resin, and therefore can be manufactured at a relatively low cost. However, the tightening torque can be sufficiently increased. Further, when the fastener is press-fitted into the storage hole of the fastener storage portion, a relatively large manufacturing tolerance of the fastener is held on the upstream side of the recess when viewed in the tightening rotation direction on the side surface. It is compensated by the elastic deformation and / or the plastic deformation of the protruding portion, and it is possible to avoid the force required for press fitting from becoming excessive or too small.

A slope view of a preferred embodiment of a tightening torque control tool configured according to the present invention as viewed from above. A slope view of the tightening torque control tool shown in FIG. 1 as viewed from below. The front view which shows a part of the tightening torque management tool shown in FIG. 1 in cross section. The plan view of the tightening torque management tool shown in FIG. The bottom view of the tightening torque management tool shown in FIG. The front view which shows a part of the combination of the tightening torque management tool shown in FIG. 1 and the nut which is a typical example of a fastener, in cross section. FIG. 6 is a cross-sectional view of the combination shown in FIG. FIG. 6 is a cross-sectional view showing a state in which 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. FIG. 7 is a cross-sectional view similar to FIG. 7, showing a modified example of the holding protrusion.

Hereinafter, the details will be further described with reference to a preferred embodiment of the tightening torque control tool configured according to the present invention and an attached drawing showing a combination of the embodiment and a nut which is a typical example of the fastener.

Explaining with reference to FIGS. 1 to 3, the tightening torque control tool indicated by No. 2 as a whole is an appropriate 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 management tool 2 includes a fastener accommodating portion 4 constituting the substantially lower half portion thereof and a tightening torque adding portion 6 constituting the substantially upper half portion thereof.

Continuing the description with reference to FIGS. 4 and 5 together with FIGS. 1 to 3, the fastener storage portion 4 has a tubular shape as a whole, and a storage hole 8 having an open free end, that is, a lower end is formed. The annular lower surface 10 of the fastener accommodating portion 4 is flat, and similarly, the annular upper surface 12 is also flat and extends parallel to the annular lower surface 10. The outer peripheral surface 14 of the fastener accommodating portion 4 has a cylindrical shape.

The inner peripheral surface of the storage hole 8 has a shape in which a recess 16 is formed in the middle of each side surface 15 of the virtual regular polygon inner peripheral surface corresponding to the torque-applied regular polygon outer peripheral surface of the fastener to be stored. is important. In the illustrated embodiment, the fastener is a hexagon nut, as will be described later, and therefore the torque-applied regular polygon outer peripheral surface of the fastener is a regular hexagon, and the virtual regular polygon inner peripheral surface (in FIG. The inner peripheral surface shown) is also a regular hexagon. Each of the recesses 16 is located on both side surfaces together with the bottom surface 16a, that is, the upstream surface 16b located on the upstream side and the downstream surface 16c located on the downstream side when viewed in the tightening rotation direction (clockwise in FIG. 4 and counterclockwise in FIG. 5). Has. The angle α formed by the bottom surface 16a and the upstream surface 16b is particularly preferably about 100 to 160 degrees, and is preferably an obtuse angle. In the illustrated embodiment, the bottom surface 16a has an arc shape forming a part of a circle concentric with the outer peripheral surface 14, and the upstream surface 16b is inclined outward with respect to the side surface 15 in the tightening rotation direction. and it extends to. It is preferable that the bottom surface 16a and the upstream surface 16b are smoothly connected via the arc-shaped boundary surface 16d. On the other hand, the downstream surface 16c extends perpendicular to the side surface 15. In the tightening rotation direction, it is convenient that the circumferential length L1 of the side surface 15a on the downstream side of the recess 16 is longer than the circumferential length L2 of the side surface 15b upstream of the recess 16 (in this case). Is clearly understood from the following description, the threshold of the tightening torque is defined by the deformation of the side surface 15a on the downstream side of the recess 16). As can be understood by referring to FIG. 3, the lower end of the inner peripheral surface of the storage hole 8 opened in the annular lower surface 10 of the fastener storage portion 4 is chamfered. In the illustrated embodiment, the fastener accommodating portion 4 is also formed with a communication hole 18 following the upper end of the accommodating hole 8. As is clearly understood by referring to FIG. 5, the cross-sectional shape of the communication hole 18 is circular, and its diameter is slightly smaller than the diameter of the circle inscribed in the virtual regular hexagon in the storage hole 8 and is stored. the boundary between the hole 8 and the communication hole 18 ring Jokatamen 20 is defined which faces downward.

In the tightening torque control tool 2 configured according to the present invention, the tightening rotation direction on the side surface 15 that defines the inner peripheral surface of the storage hole 8 (clockwise in FIG. 4 and counterclockwise in FIG. 5). It is important that the holding protrusion is provided in the portion 15b located on the upstream side of the recess 16. In the illustrated embodiment, the holding protrusion extends in the axial direction of the storage hole 8 (vertical direction in FIG. 3, direction perpendicular to the paper surface in FIG. 5), preferably substantially parallel to the axis of the storage hole 8. The rib 21 is formed. In the illustrated embodiment, holding protrusions or ribs 21 are formed in each of the six side surface 15 portions 15b. Each of the ribs 21 extends substantially parallel to the axis of the storage hole 8 from the upper end to the vicinity of the lower end of the storage hole 8, as is clearly understood by referring to FIGS. 2 and 3. In particular, when the fastener has a nominal diameter of M8, M10 or M12, the protruding height H of the rib 21 is about 0.1 to 0.5 mm, and the circumferential width W of each of the ribs 21 is 0.1 to 0. It is preferably about 5 mm. It is convenient that the cross-sectional shape of the protruding end of the rib 21 is a semicircular shape as shown in FIG. In the illustrated embodiment, the ribs 21 are formed in all of the six side surface 15 portions 15b, but if desired, for example, the three side surfaces 15 located every other surface or facing each other in the radial direction. It is also possible to form the rib 21 only on the portion 15b of the two side surfaces 15 located therein.

The ribs 21 constituting the holding protrusion are not only the portion 15b located on the upstream side of the recess 16 when viewed in the tightening rotation direction on the side surface 15, but also downstream of the recess 16 when viewed in the tightening rotation direction on the side surface 15. It can also be formed on the side portion 15a. However, when it is also formed in the portion 15a located on the downstream side of the recess 16 in the tightening rotation direction on the side surface 15, when the tightening torque reaches the threshold value as described later, the tightening rotation direction on the side surface 15 Since the portion 15a located on the downstream side of the recess 16 is mainly deformed, the rib is deformed over the entire portion prior to the deformation of the side surface 15, and the tightening torque reaches the threshold value due to this. The tightening torque control tool 2 tends to be separated from the fastener before. Therefore, it is desirable not to dispose the rib 21 in the portion 15a located on the downstream side of the recess 16 when viewed in the tightening rotation direction on the side surface 15.

Continuing the description with reference to FIGS. 1 to 4, the tightening torque adding portion 6 extending upward from the annular upper surface 12 of the fastener accommodating portion 4 also has a tubular shape as a whole, and is a through hole extending in the vertical direction. 22 has. As is clearly understood from FIG. 3, the through hole 22 communicates with the storage hole 8 through the communication hole 18. The cross-sectional shape of the through hole 22 is circular, the diameter thereof is further smaller than the diameter of the communication hole 18, and a downwardly facing annular shoulder surface 24 is defined at the boundary between the through hole 22 and the communication hole 18. ing. The outer peripheral surface 26 and the upper surface 28 of the tightening torque adding portion 6 preferably have a shape and dimensions corresponding to the outer peripheral surface and the upper surface of the fastener housed in the fastener storage portion 4, and are shown in the illustrated embodiment. The outer peripheral surface 26 of the tightening torque adding portion 6 has a regular hexagonal shape corresponding to the outer peripheral surface of the hexagon nut (therefore, the outer diameter of the tightening torque adding portion 6 is smaller than the outer diameter of the fastener accommodating portion 4). The main portion of the upper surface 28 is flat, but the outer peripheral portion of the corner portion is chamfered. The diameter of the through hole 22 of the tightening torque addition portion 6 is slightly larger than the outer diameter of the shaft portion of the bolt to which the hexagon nut is fastened. When fastening to the bolt, the shaft portion of the bolt inserts the communication hole 18 of the fastener accommodating portion 4 and the through hole 22 of the tightening torque adding portion 6 according to the progress of fastening.

The tightening torque control tool 2 as described above can be distributed on the market by itself, but FIGS. 6 and 7 (in FIG. 7, chamfering at the lower end of the inner peripheral surface of the storage hole 8 for simplification of the drawing). The processing is omitted, and the rib 21 is somewhat elastically or plastically deformed by press-fitting the fastener, that is, the hexagon nut 30, into the storage hole 8, but the rib 21 is not shown. As shown in (shown overlaid on the hexagon nut 30 in a state where the 21 is not deformed), it is convenient to distribute the nut in combination with the fastener on the market. In the embodiments shown in FIGS. 6 and 7, a hexagon nut 30 is shown as a typical example of the fastener. The outer peripheral surface 32 of the hexagon nut 30 is a regular hexagon, and when the manufacturing error of the hexagon nut 30 is sufficiently small, it is slightly larger than the virtual regular hexagon regarding the storage hole 8 formed in the fastener storage portion 4 ( In other words, the virtual regular hexagon of the storage hole 8 of the fastener storage portion 4 in the tightening torque control tool 2 is set smaller than the outer peripheral surface 32 which is the regular hexagon of the hexagon nut 30). Then, the main portion of the hexagon nut 30, that is, the portion excluding the lower end portion, is press-fitted into the storage hole 8 of the fastener storage portion 4, and is formed inside the upper surface outer peripheral edge portion 34 of the hexagon nut 30. when the upper surface of the projection 36 is in the form it is having no said annular shoulder surface 24 is brought into contact (the fastener housing portion hexagonal nut 30 is a cylindrical projection 36 which is housed in the housing hole 8 of the 4 hex nuts The outer peripheral edge portion 34 of the upper surface of 30 is in contact with the annular shoulder surface 20). The hexagon nut 30 has a rib 21 on the side surface of the hexagon nut 30 together with a portion 15a located on the downstream side of the recess 16 when viewed in the tightening rotation direction (clockwise in FIG. 4 and counterclockwise in FIG. 5). It is held in the storage hole 8 by pressure welding.
Therefore, as described above, 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 storage hole 8 is relatively small. On the other hand, the manufacturing tolerance of the hexagon nut 30 is relatively large, and therefore the manufacturing error of the outer peripheral surface of the hexagon nut 30 is relatively large. A relatively large manufacturing error of the outer peripheral surface of the hexagon nut 30 with respect to the inner peripheral surface is compensated by the elastic or plastic deformation of the rib 21 formed in the required portion of the inner peripheral surface of the storage hole 8. Therefore, it is possible to avoid the force required for press-fitting the hexagon bolt 30 into the storage hole 8 to be excessive or too small.

Explaining how to use the tightening torque control tool 2 as described above, if the hexagon nut 30 is already combined with the tightening torque control tool 2, the shaft portion 38 of the bolt to which the hexagon nut 30 should be fastened is described. Fitted in (FIG. 6) (If the hexagon nut 30 is not combined with the tightening torque control tool 2, the hexagon nut 30 temporarily fastened to the bolt is inserted into the fastener storage portion 4 of the tightening torque control tool 2. It is stored in the formed storage hole 8). Next, an appropriate tightening tool (not shown) is engaged with the outer peripheral surface of the tightening torque adding portion 6 to rotate in the tightening rotation direction (clockwise in FIG. 4 and counterclockwise in FIG. 5). The torque applied from the fastener to the tightening torque adding portion 6 is transmitted to the hexagon nut 30 via the fastener accommodating portion 4, whereby the hexagon nut 30 is tightened to the shaft portion 38 of the bolt. When the hexagon nut 30 travels over a relatively long distance in the axial direction with respect to the shaft portion 38 of the bolt, the shaft portion 38 of the bolt is a fastener as shown by the alternate long and short dash line in FIG. It enters the communication hole 18 formed in the storage portion 4 and the through hole 22 formed in the tightening torque adding portion 6, and inserts the communication hole 18 and the through hole 22.

When the tightening torque transmitted to the hexagon nut 30 exceeds a predetermined threshold value, FIG. 8 (also in FIG. 8, as in FIG. 7, the chamfering process at the lower end of the inner peripheral surface of the storage hole 8 is shown for simplification of the drawing. (Omitted), the inner peripheral surface of the storage hole 8 formed in the fastener storage portion 4, particularly the portion downstream of the recess 16 when viewed in the tightening rotation direction (more specifically, tightening). From the boundary region between the upstream side surface 15 and the downstream side surface 15 when viewed in the attachment rotation direction, the portion downstream of the recess 16 of the upstream side surface 15) is on the side opposite to the tightening rotation direction. It is pressed toward and deformed, so that the tightening torque management tool 2 idles with respect to the hexagon nut 30, and thus the hexagon nut 30 is fastened to the bolt with the required tightening torque. When the tightening torque control tool 2 starts idling with respect to the hexagon nut 30, the upstream surface 16b of the recess 16 of the storage hole 8 in which the outer peripheral surface corner portion of the hexagon nut 30 is formed in the fastener storage portion 4. However, in the illustrated embodiment, since the bottom surface 16a of the recess 16 and the upstream surface 16b form an obtuse angle, the hexagon nut 30 is moved from the outer peripheral surface corner portion to the upstream surface 16b of the recess 16. It is possible to avoid that the applied force is appropriately buffered or eliminated, cracks are generated in the fastener accommodating portion 4, and the fastener accommodating portion 4 is damaged. After the tightening torque control tool 2 starts idling with respect to the hexagon nut 30, the bolt shaft 38 is tightened with the required tightening torque, and the tightening torque control tool 2 is sufficiently easily separated from the hexagon nut 30. be able to.

In the above-described embodiment, the holding protrusion is composed of one rib 21 extending in the axial direction of the storage hole 8, but if desired, the axial direction of the storage hole 8 is spaced apart from the axial direction or the circumferential direction. A plurality of ribs extending in the circumferential direction, one extending in the circumferential direction of the storage hole 8, a plurality of ribs extending in the circumferential direction at intervals in the axial direction or the circumferential direction of the storage hole 8, or a plurality of appropriately arranged ribs. The holding protrusion can also be constructed from the protrusions (preferably having a circular cross-sectional shape). FIG. 9 illustrates yet another embodiment of the holding protrusion. In such an embodiment, the entire surface of the portion 15b located on the upstream side of the recess 16 when viewed in the tightening rotation direction (counterclockwise in FIG. 9) on the side surface 15 (see FIG. 5). A ridge 40 is formed over the ridge 40, and a groove 42 extending along the ridge 40 is formed on the back surface side of the ridge 40. In such an embodiment, the raised portion 40 is pressed against the side surface of the hexagon nut 30 together with the portion 15a located on the downstream side of the recess 16 when viewed in the tightening rotation direction (counterclockwise direction in FIG. 9) on the side surface 15. By doing so, the hexagon nut 30 is held in the storage hole 8. The relatively large manufacturing error of the outer peripheral surface of the hexagon nut 30 with respect to the inner peripheral surface of the storage hole 8 is compensated by the elastic deformation of the raised portion 40, and the force required to press-fit the hexagon bolt 30 into the storage hole 8 is excessive. Alternatively, it is avoided as much as possible to be underestimated.

2: Tightening torque control tool 4: Fastener storage part 6: Tightening torque addition part 8: Storage hole 15: Side surface 16: Recess 16a: Bottom surface of the recess 16b: Upstream surface of the recess 16c: Downstream surface of the recess 18: Communication hole 21: Rib (holding protrusion)
22: Through hole 30: Hexagon nut 38: Bolt shaft

Claims (9)

Includes a fastener storage unit and a tightening torque addition unit integrally formed from synthetic resin.
A storage hole having a free end opened is formed in the fastener storage portion, and the inner peripheral surface of the storage hole is each of the regular polygon inner peripheral surfaces corresponding to the torque-applied regular polygon outer peripheral surface of the fastener. It is a form in which a recess is formed in the middle part of the side surface.
A holding protrusion is provided on a portion of the side surface of the inner peripheral surface of the regular polygon located on the upstream side of the recess when viewed in the tightening rotation direction.
When the tightening torque applied to the tightening torque adding portion and transmitted to the fastener through the fastener storage portion exceeds the threshold value, the inner peripheral surface of the storage hole is deformed and the fastener is fastened to the fastener. The tool compartment now spins, thus managing the tightening torque of the fasteners.
A tightening torque management tool that is characterized by this. The holding protrusion Ru ribs der extending in the axial direction of the receiving hole, the torque management fastener according to claim 1. The projection height of the ribs Ri 0.1 to 0.5mm der, the circumferential width of the rib is 0.1 to 0.5mm, torque management fastener of claim 2 wherein. The tightening torque management tool according to claim 2 or 3, wherein the cross-sectional shape of the protruding end of the rib is a semicircular shape. Claims 1 to 4, wherein the outer peripheral surface of the torque-applied regular polygon is a regular hexagon, and the holding protrusion is arranged at a portion located on the upstream side of the recess on each of the six side surfaces. The tightening torque control tool described in either. The outer peripheral surface of the該締tightening torque adding section is a regular polygon that corresponds to the torque addition regular polygonal outer peripheral surface of the fastener, the torque management fasteners according to any one of claims 1 to 5. A combination of the tightening torque control tool according to any one of claims 1 to 6 and a fastener that is at least partially housed in the storage hole of the tightening torque control tool. The combination according to claim 7, wherein the fastener is press-fitted into the storage hole. The combination according to claim 7 or 8, wherein the fastener is a hexagon nut.

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