JP2011089527A - Screw part with washer and tool for mounting washer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a screw part with a washer, a screw part, a washer, and a tool for mounting a washer, surely preventing loosening. <P>SOLUTION: The screw part with the washer is formed in a manner that the screw part such as a nut, a bolt, or the like is formed with head projections on the back face of the head of the screw part, the washer is formed with washer projections engageable with the head projections and is arranged on a back face side of the screw part, the screw part is connected to the washer with the washer mounting tool, and the washer mounting tool has a head side mounting part and a bottom side mounting part respectively locked to the head of the screw part and the washer. In the screw part such as the nut or the bolt with the head projections formed on the back face of the head of the screw part, a head locking part is formed on the head and can lock the head side mounting part of the washer mounting tool. The washer mounting tool includes a cylindrical body capable of being laid over the head of the screw part such as the nut or the bolt and the outer periphery of the washer arranged on the back face side. The body includes the bottom side mounting part mountable to the screw part and the washer side mounting part mountable to the washer. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a screw with a washer in which a washer is attached to the back of the head of a screw such as a nut or a bolt, a screw that can be used for the screw, a washer that can be attached to the screw, and a washer that can be set on the back of the head. It relates to ingredients.

  2. Description of the Related Art Conventionally, there have been screws that are set so that a lock washer for locking is not dropped on the back of the head of a screw such as a bolt or nut (hereinafter simply referred to as “screw”). There is.

The screw of Patent Document 1 is pre-attached to the engagement skirt that projects continuously and integrally from the bottom surface of the head of the screw so that the central hole of the disc spring washer is relatively free-movable and tightened. The restoring force of the disc spring washer prevents the screws from loosening.
In the screw of Patent Document 2, a washer is attached to the neck part under the head of the screw, and when the screw is tightened, the chevron protrusions provided on the back surface of the head of the screw and the surface of the washer mesh with each other. To prevent loosening of the screws.

JP 2002-122120 A JP 2006-242324 A

In Patent Document 1, the mounting of the disc spring washer to the engagement skirt was troublesome, and in Patent Document 2, the mounting of the washer to the neck portion on the back side of the head of the screw was troublesome.
In Patent Documents 1 and 2, since the washer is loosely attached with a play on the neck of the screw, the shaft center of the screw and the center of the center hole of the washer are easily misaligned, and the angle protrusions of the screws are There has been a problem that the locking of the is easy to loosen.

  It is an object of the present invention to solve the above-mentioned problems. Screws with washers, screws that can be used for them, washers, and a washer can be easily attached to the screws without a troublesome mounting operation such as caulking. It is to provide a simple washer mounting jig.

  The screw with a washer of the present application has a washer in which a washer protrusion that can be engaged with the head protrusion is formed on the back surface side of the screw in which a head protrusion is formed on the back surface of the head of a screw such as a nut or a bolt. The screw and the washer are connected by a washer attachment, and the washer attachment has its head side attachment portion locked to the head of the screw and the hem side attachment portion locked to the washer.

  The screw of the present application is a screw in which a head protrusion is formed on the back surface of the head of a screw such as a nut or a bolt. A head locking portion is formed on the head, and the head locking portion is a washer. The head side attachment portion of the attachment can be locked.

  The screw of the present application is a screw in which a head protrusion is formed on the back surface of the head of a screw such as a nut or a bolt, and a protrusion protruding forward from the back surface is formed on a part of the back surface of the head. A head protrusion is formed on the protrusion to be engaged with the washer protrusion on the washer surface.

  In the washer of the present application, a washer protrusion that can be engaged with a head protrusion formed on the back surface of the head of the screw is formed on the surface of the washer substrate, and a ring-shaped outer groove is provided on the back surface of the washer substrate in the circumferential direction of the back surface of the washer substrate. Indented projections which are formed in a more recessed shape and can bite into the body to be clamped are formed to protrude from the back surface of the washer substrate at several places in the circumferential direction in the outer groove, and recesses are formed on the outer periphery of the respective biting projections. It is formed so as to be recessed from the back surface.

  In the washer of the present application, a washer projection that can mesh with a head projection formed on the back surface of the head of the screw is formed on the surface of the washer substrate, and a washer locking portion is formed on the outer peripheral portion or the bottom surface of the washer substrate. The locking portion is formed so that the hem side mounting portion of the washer mounting tool can be mounted.

  The washer fitting of the present application is provided with a cylindrical main body that can be put on the outer periphery of a head of a screw such as a nut or a bolt and a washer arranged on the back side thereof, and a hem that can be attached to the screw on the main body. A side attachment portion and a washer side attachment portion that can be attached to the washer are provided.

The screw with washer of the present invention has the following effects.
(1) Since the washer is attached to the inside of the washer attachment, there is no trouble of setting the washer one by one during the tightening operation of the screws.
(2) Since the washer is provided with a washer projection that can mesh with the head projection of the screw, the washer projection and the head projection can be reliably meshed with each other simply by tightening the screw, so that the screw is difficult to loosen.
(3) If the inner diameter of the washer fitting is the same as the outer circumference of the washer, the washer will not fall off simply by pushing (setting) the washer into the washer fitting, and it will be troublesome to perform caulking work to prevent the washer from falling off. There is no.
(4) Since the washer set in the washer attachment is positioned by the washer attachment and is not displaced, the engagement between the head projection of the screw and the washer projection of the washer is ensured and the screws are not easily loosened.
(5) If the inner diameter of the washer attachment is made slightly larger than the outer periphery of the washer, the washer will not come off the screws just by tightening the hem of the washer attachment after inserting the washer inside the washer attachment. Easy to install the washer

The screws of the present application have the following effects.
(1) Since the head side mounting portion that can lock the washer mounting tool is on the outer periphery or the bottom surface of the head, locking (attaching) of the washer mounting tool to the screws is easy and reliable.
(2) Since a protrusion protruding forward from the back surface is formed on a part of the back surface of the head, and the protrusion is formed with a head protrusion that engages with the washer protrusion on the surface of the washer, contact with the washer The area is reduced and tightening is possible even with a weak force.

The washer of the present application has the following effects.
(1) Since the washer locking portion capable of locking the washer mounting tool is provided, it is easy to mount the washer mounting tool.
(2) Since there is a biting projection on the back surface of the washer, if the screws are tightened, the biting projection will bite into the body to be tightened, so that the washer is difficult to loosen and the screws are also difficult to loosen.
(3) Since there is a recess on the outside of the biting protrusion, the meat of the clamped body that rises when the biting protrusion bites into the clamped body can penetrate into the recess, and even if the screw is tightened strongly, the raised part will be in the way Therefore, it is possible to securely tighten to the root of the biting protrusion. Further, when the raised meat enters the recess, the washer is fixed to the clamped body, and the washer is less likely to loosen and the screws are less likely to loosen.
(4) If the biting protrusion on the back surface of the washer is formed on the back surface of the washer surface where there is no washer protrusion, the biting protrusion may be crushed when the washer protrusion is pressed, or Since the protrusions are not crushed, the formation of the protrusions is facilitated, the defect rate of the protrusions to be formed is reduced, and the yield is improved, so that the washer manufacturing cost is reduced.
(5) A ring-shaped outer groove is formed in the circumferential direction of the back surface of the washer substrate so as to be recessed from the back surface of the washer substrate, and there are biting projections that can bite into the clamped body at several locations in the circumferential direction of the outer groove. Since it is formed so as to protrude from the back surface and the recess is formed in the outer periphery of each biting projection so as to be recessed from the back surface of the washer substrate, this washer is incorporated into the screws with the washer mounting tool of the present application and tightened with the screws. Even if the screws are loosened and tightened again after tightening to the body to be tightened, the meat of the body to be tightened that has risen due to the biting protrusions biting into the body to be tightened during the previous tightening passes through the outer groove when tightening again. Therefore, it is possible to secure the tightening again without interfering with the washer tightening, and secure the tightening even after repeated use.

The washer fitting of the present application has the following effects.
(1) Since it has a cylindrical shape that can be put on the outer periphery of the head of the screw and the washer arranged on the back surface side thereof, it can be easily attached to the screw.
(2) Since the head-side mounting portion that can be locked to the head locking portion of the screw and the hem-side mounting portion that locks to the washer locking portion of the washer are provided, the screw and the washer can be connected. Easy.

Sectional drawing which shows an example of the screws with a washer of this invention. An example of the washer attachment tool of the present invention is shown, (a) is a plan view of (b), (b) is a sectional view of (a), and (c) is a bottom view of (b). The external view which shows the other example of the washer attachment tool of this invention. (A) is another example of the screw with a washer of the present invention, and is a cross-sectional view of an example in which a washer locking portion is provided on the bottom surface of the washer, and (b) is used for the screw with a washer of (a). Sectional drawing of a washer attachment tool. (A) is another example of the screw with a washer of the present invention, and is a cross-sectional view when the peripheral wall of the washer attachment is straight, and (b) is a washer attachment used for the screw with a washer in (a). Sectional drawing of a tool, (c) is a bottom view of (a). (A) is other examples of the screw with a washer of the present invention, and is a sectional view in case the peripheral wall of a washer attachment tool is divided into four parts, (b) is a bottom view of (a). (A) is another example of the screw with a washer of the present invention, and is a cross-sectional view when the screw is a bolt, and (b) is a cross-sectional view of a washer used for the screw with a washer of (a). It is an example of the washer used for the screws with the washer of the present invention, where (a) is a plan view, (b) is a side view, (c) is a back view, and (d) is a bite formed on the back surface. Detailed explanatory drawing which shows protrusion and the recessed part currently formed in the circumference | surroundings. The fragmentary sectional view which shows the usage example of the screws with a washer of this invention. (A) is a back view showing an example of a washer used for the screw with washer of the present invention, and (b) to (d) are biting protrusions formed on the back surface of the washer and recesses formed around the back surface. Detailed explanatory drawing. (A) is a fragmentary sectional view which shows an example of the screw projection of the screw used for the screw with a washer of the present invention, and (b) is the washer projection and the biting projection of the washer used for the screw with a washer of the present invention. FIG. 4 is a detailed explanatory view of the concave portion, and FIG. Sectional drawing which shows the other examples of screws and washers of this invention. (A) is a back view which shows the other example of the washer of this invention, (b) is sectional drawing of (a).

(Embodiment 1 of screw with washer)
An example of a screw with a washer according to the present invention is shown in FIG. 1 in the case where the screw 1 is a nut, and the screw 1 is covered with a washer fitting 2 from above, so that the upper of the washer fitting 2 is narrowed. The head side attachment portion 3 is locked to the inclined surface 5 of the head 4 of the screw 1, and the hem side attachment portion 6 of the washer attachment 2 is accommodated (set) inside the peripheral wall 7 of the washer attachment 2. The washer 8 is attached to the screws 1 so as not to fall off by being engaged with a washer engaging portion 9 formed on the side surface of the washer 8. A head projection 14 is formed on the back surface of the head of the screw 1, and a washer projection 15 is formed on the surface of the washer 8. There is a gap 25 between both projections, and the washer 8 is vertically moved between the gaps 25. It is possible to slide. The bottom surface of the washer 8 protrudes below the hem of the peripheral wall 7 of the washer attachment 2.

  The head-side mounting portion 3 is tapered toward the upper side, and its inner diameter is made smaller than the inclined surface 5 of the head 4 of the screw 1, and the washer mounting tool 2 is put on the screw 1, the head The side attachment portion 3 is automatically locked to the inclined surface 5 of the head 4 of the screw 1.

  The skirt side attaching portion 6 is formed into a substantially hemispherical protrusion by pushing inward several places in the circumferential direction of the peripheral wall 7. The washer locking portion 9 is formed by making the outer peripheral portion of the bottom surface of the washer 8 one step lower than the bottom hole central hole P side of the washer 8.

  As shown in FIGS. 2 (a) to 2 (c), the washer attachment 2 has a restoring force capable of expanding and reducing the diameter of the peripheral wall 7 by making cuts 11 in the vertical direction at several positions in the peripheral direction of the peripheral wall 7. Thus, when the washer attachment tool 2 is placed on the screws 1 and the hem side attachment portion 6 of the peripheral wall 7 is set on the washer locking portion 9 of the washer 8, the peripheral wall 7 expands in diameter and the hem side attachment portion 6 It is also possible to lock the washer 8 to the washer locking portion 9 without difficulty and to automatically reduce the diameter of the peripheral wall 7 after the locking so that the washer 8 is held.

(Embodiment 2 of screw with washer)
As another example of the screw 1 with a washer of the present invention, the screw shown in FIGS. 4A and 4B is also a case where the screw 1 is a nut, and its basic configuration is the same as that shown in FIG. As shown in FIG. 4 (b), the lower end (hem) 12 of the peripheral wall 7 of the washer fitting 2 is bent inward to form the skirt side attachment 6, and the washer fitting 2 is screwed. 1 is attached to the inclined surface 5 of the screw 1, and the peripheral wall of the washer fitting 2 from the lower end opening 10 of the hem 12 of the washer fitting 2. 7, the washer 8 is pushed into and set in the base 7, and the hem side attachment portion 6 is locked to the washer locking portion 9 of the washer 8. Also in this case, as shown in FIG. 4 (b), the washer attachment tool 2 is obtained by making incisions 11 in the longitudinal direction at several places in the circumferential direction of the peripheral wall 7 to give the peripheral wall 7 a restoring force capable of expanding and reducing the diameter. When the hem side attaching portion 6 of the peripheral wall 7 is set on the washer engaging portion 9 of the washer 8 by covering the screw 1 with the screw 1, the peripheral wall 7 is expanded in diameter and the hem side attaching portion 6 is the washer engaging portion of the washer 8. The peripheral wall 7 is automatically reduced in diameter after being locked, and the washer 8 is held.

(Embodiment 3 of screw with washer)
In the embodiment of FIG. 1, the hemispherical hem side locking portion 6 protrudes from the inside of the peripheral wall 7, and in the embodiment of FIGS. 4A and 4B, the hem side attachment portion 6 connects the skirt 12 of the peripheral wall 7. In the present invention, it is formed before the washer is set by bending inwardly. However, in the present invention, the skirt 12 of the peripheral wall 7 of the washer fitting 2 is kept straight as shown in FIG. After the washer 8 is accommodated in the peripheral wall 7 from 10, the skirt 12 of the peripheral wall 7 is bent inward as shown in FIG. It can also be locked. Also in this case, as shown in FIG. 3, if the circumferential wall 7 is provided with incisions 11 in the longitudinal direction and the circumferential wall 7 is provided with a restoring force capable of expanding and contracting, the bottom of the circumferential wall 7. It becomes easy to bend 12 inside.

(Embodiment 4 of screw with washer)
FIGS. 6A and 6B show an example of the screw 1 with a washer of the present invention before the washer is attached. The basic structure of the screw 1 with a washer is the same as that of FIGS. 1A, 1B, 4A, and 4B, and the difference is that the peripheral wall 7 of the washer mounting tool 2 is moved in the circumferential direction. A hemispherical hem-side attachment portion 6 projecting inwardly is formed on each peripheral wall 7, and the hem-side attachment portion 6 is attached to a washer locking portion 9 (see FIG. 1). The washer 8 can be held by being locked to FIG.

(Embodiment 5 of screw with washer)
FIGS. 7A and 7B show another example of the screw 1 with a washer according to the present invention, in which the screw 1 is a bolt having a screw rod 13 under the head 4. The configuration other than that provided is the same as in the first to fourth embodiments.

(Embodiment 1 of screw)
An example of an embodiment of the screw 1 of the present invention is shown in FIG. The screw 1 is a nut, and a chevron-shaped head protrusion 14 shown in FIG. 1 is continuously formed radially around the back surface of the head 4 as shown in FIG. The number of crests and grooves of the head projection 14 and the inclination angle of the crest are designed so that they can mesh with the washer projection 15 on the surface of the washer 8. The angle of the head protrusion 14 can be arbitrarily selected. As shown in FIG. 11 (a), a gently sloping tightening slope 14a is formed on the front side in the tightening direction (left side of FIG. 11 (a)), and the rear side in the tightening direction opposite to that (right side of FIG. 11 (a)). It has a mountain shape provided with a sloping stop slope 14b having a steep slope. The shape of the head protrusion 14 is not limited to that shown in FIG. 11A, and the inclination angle of the tightening slope 14a and the locking stopper 14b can be selected to be an angle suitable for fastening and locking.

(Embodiment 2 of screw)
In FIG. 1, the head side attachment portion 3 of the washer attachment 2 is locked to the inclined surface 5 of the screw 1, but in the screw 1 of the present invention, the inclined surface is not locked to the inclined surface 5. In addition to 5, a screw locking portion (not shown) is formed on the head 4 so that the head side mounting portion 3 of the washer fitting 2 can be locked on the screw locking portion. You can also. The shape and the formation position of the screw locking portion can be designed in any shape where the head side mounting portion 3 of the washer mounting member 2 can be locked.

(Embodiment 3 of screw)
As shown in FIG. 12, the screw 1 of the present invention has a washer locking portion 9 on the outer peripheral portion of the back surface of the head 1, and a protrusion 27 that protrudes from the center portion 28 toward the bottom side (downward in FIG. 12). And the head projection 14 may be formed on the projection 27.

(Embodiment 4 of screw)
The screw 1 of the present invention may be a bolt as shown in FIG. The diameter, length, thread pitch, and the like of the screw rod 13 can be set to desired dimensions.

(Embodiment 1 of washer)
As an example of the embodiment of the washer of the present invention, the one shown in FIGS. 8A to 8D is formed with angled washer projections 15 radially from the center hole P toward the outer peripheral edge R at four locations on the washer surface. Several four washer protrusions 15 are continuously formed in the circumferential direction. The washer protrusion 15 can also be formed on the entire circumference of the surface of the washer substrate. As shown in FIG. 1, the washer protrusion 15 has a pitch and a peak height (groove depth) that can engage with the head protrusion 14 formed on the back surface of the head of the screw 1. As shown in FIGS. 11B and 11C, the individual washer protrusions 15 are tightened with a gentle inclination on the rear side in the tightening direction (the right side of FIG. 11B) opposite to the inclination angle of the head protrusion 14. An inclined surface 15b is formed, and has a mountain shape with an abrupt and loosening-preventing inclined surface 15a on the opposite side in the tightening direction (left side of FIG. 11B). The shape of the washer protrusion 15 is not limited to that shown in FIGS. 10B and 10C, and the inclination angle can be selected according to the inclination of the head protrusion 14 (FIG. 10A).

  As shown in FIGS. 10A to 10D, a biting protrusion 16 and a recess 17 are formed on the back surface of the washer 8. The biting protrusion 16 has a sharp triangular pyramid shape as shown in FIG. 10 (b) or a sharp inverted pyramid shape as shown in FIG. 10 (c), and is incorporated in the screw 1 as shown in FIG. When the washer 8 is tightened with the screws 1, it is shaped so as to be able to bite into the body 20 (FIG. 9). The biting protrusions 16 are preferably hardened to increase the hardness so that the biting protrusions 16 can easily bite into the metallic object 20. The inclination angle of the biting protrusion 16 can be set to an arbitrary angle as long as it is easy to bite and is not easily removed. Although the biting protrusions 16 in FIG. 10A are formed at three locations in the circumferential direction of the back surface of the washer 8, the number, formation position, interval, etc. may be other than that. The biting protrusion 16 in FIG. 10B gradually protrudes outward from the top to the bottom, and the lower end (tip) protrudes outward from the outer peripheral edge R of the washer body. 8 (a) to 8 (c) are formed on a portion of the back surface of the washer 8 where the angled washer projections 15 are not formed on the front surface of the washer 8. It can also be formed on the back surface of the portion where 15 is formed.

  As shown in FIGS. 8, 10 (c), and 10 (d), a groove-like recess 17 is formed around the root of the biting protrusion 16. The shape of the recess 17 is not limited to that shown in the figure, but may be any other shape such as a circular ring shape, a hexagonal ring shape, or an octagonal ring shape. As shown in FIG. 9, the concave portion 17 has a protruding portion 21 (FIG. 11C) that is generated by biting the biting protrusion 16 into the tightened body 20, and even if the screws 1 are strongly tightened, the protruding portion 21. This is to prevent the biting protrusion 16 from biting into the clamped body 20 to its root and surely biting into the clamped body 20. The concave portion 17 may not be formed as shown in FIG.

  The washer of the present invention may be as shown in FIG. In this, a ring-shaped outer groove 26 is formed on the bottom surface of the washer, and biting protrusions 16 are projected at four circumferential positions in the outer groove 26, and a recess 17 is formed on the outer periphery of each biting protrusion 16. is there. Both the outer groove 26 and the recess 17 are recessed by one step from the bottom surface of the washer, and the leading end of the biting projection 16 protrudes to the end of the washer bottom surface (downward in FIG. 13).

(Usage example 1 of screws with washers)
In order to connect two thick plate-like tightened bodies 20 as shown in FIG. 9 using the screw 1 with a washer of the present invention, a screw rod 13 of a screw with a washer (bolt) is connected to the tightened body 20. Then, the screw 1 with a washer 1 or the screw 1 with a washer 8 set inside the peripheral wall 7 of the washer fitting 2 (nut) is screwed into the lower part of the screw rod 13 protruding from the clamped body 20, and the nut The two clamped bodies 20 are tightened and connected by rotating the bolt, the bolt, or both. In this case, tightening proceeds while the washer protrusion 15 of the washer 8 and the head protrusion 14 on the back of the head of the screw 1 are engaged, and the biting protrusion 16 of the washer 8 bites into the body to be tightened 20. At this time, even if the surface of the clamped body 20 rises and protrudes due to the biting of the biting protrusion 16, the protruding portion 21 (FIG. 11C) enters the recess 17 around the root of the biting protrusion 16. Bite into the body 20 to be tightened to the base, the back surface of the washer 8 is brought into close contact with the surface of the body 20 to be tightened, and the two bodies 20 to be tightened are securely fixed. In this case, the washer projection 15 of the washer 8 and the head projection 14 of the bolt are securely engaged with each other by tightening, preventing reverse rotation of the washer 8 and preventing loosening of tightening.

  Screws with washers of the present invention are not limited to bolts and nuts, but are used for various types of shoes, such as golf shoes, shoes for athletics spikes, soccer shoes, etc., civil engineering, architecture, machinery, wire towers, elevators It can be used in all fields that require screws such as agricultural machinery, fishing machinery, railway vehicles, and automobiles.

DESCRIPTION OF SYMBOLS 1 Screws 2 Washer attachment 3 Head side attachment part 4 Head 5 (Screw head part) inclined surface 6 Bottom side attachment part 7 Peripheral wall 8 Washer 9 Washer locking part 10 Lower end opening part 11 Notch 12 Bottom part 13 Screw rod 14 Head projection 14a (for head projection) Tightening slope 14b (for head projection) Locking slope 15 Washer projection 15a Locking slope 15b (for washer projection) Tightening slope (for washer projection) 16 Intrusion protrusion 17 Concave part 20 Clamped body 21 Projection part (swelled part of meat of clamped body)
25 Clearance (between head protrusion and washer protrusion) 26 Outer groove 27 Protrusion 28 Center part P (Washer) center hole R (Washer) outer periphery

Claims (6)

  A washer having a washer protrusion formed to engage with the head protrusion is disposed on the back surface side of the screw having a head protrusion formed on the back surface of the head of a screw such as a nut or a bolt. Are connected by a washer mounting tool, and the washer mounting tool is characterized in that the head side mounting portion is locked to the head of the screw and the hem side mounting portion is locked to the washer.   In a screw having a head protrusion formed on the back surface of the head of a screw such as a nut or bolt, a head locking portion is formed on the head, and this head locking portion is on the head side of the washer attachment Screws characterized in that the attachment portion can be locked.   In a screw in which a head protrusion is formed on the back surface of the head of a screw such as a nut or a bolt, a protrusion protruding forward from the back surface is formed on a part of the back surface of the head, and the washer surface Screws characterized in that a head projection is formed to be engaged with the washer projection.   A washer projection that can mesh with the head projection formed on the back surface of the screw head is formed on the surface of the washer substrate, and a ring-shaped outer groove is formed in the circumferential direction of the back surface of the washer substrate that is recessed from the back surface of the washer substrate. The biting protrusions that can bite into the clamped body are formed to protrude from the back surface of the washer board at several circumferential positions in the outer groove, and the recesses are recessed from the back surface of the washer board at the outer periphery of each biting protrusion. A washer that is formed of   A washer protrusion that can mesh with a head protrusion formed on the back surface of the head of the screw is formed on the surface of the washer substrate, a washer locking portion is formed on the outer peripheral portion or the bottom surface of the washer substrate, and the washer locking portion is a washer. A washer characterized in that it can be attached to the hem side attachment portion of the attachment.   It has a cylindrical main body that can be put on the outer periphery of the head of a screw such as a nut or a bolt and the washer arranged on the back side of the screw, and a hem side mounting portion that can be attached to the screw on the main body, and a washer A washer mounting tool, comprising a washer side mounting portion that can be mounted.

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