JP2001124038A - Fastening tool with preparatory hole boring mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fastening tool equipped with a preparatory hole boring mechanism capable of performing simultaneously the preparatory hole boring and fastening tool insertion to a member to which fastening is made. SOLUTION: The fastening tool 1 with preparatory hole boring mechanism is composed of a drawout rod 2, a sleeve 3, and a drill 4 for enlargement of the diameter. The drawout rod 2 has drill part 2a, and also at the tail, a head part 2b having a greater diameter than the trunk part. A male thread portion 2d is provided in the trunk of the drawout rod 2, and the drill 4 is attached to the trunk in its part between the male threaded portion 2d and the drill part 2a. Receiving a force exceeding a certain level applied from above, the drill 4 separates from the rod 2. The sleeve 3 is made of a material deformable plastically. A female threaded portion 3b to be engaged with the male threaded portion 2d of the rod 2 is formed on the inner surface of the sleeve 3 at its bottom.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fastener having a pilot hole punching mechanism used for, for example, mutually fixing a plurality of plate members.

[0002]

2. Description of the Related Art A blind rivet has been conventionally used as a fastener for mutually fixing a plurality of plate members. As shown in FIG. 8 (a), the blind rivet includes a drawing rod (stem) 50a having a spherical head and a sleeve 50c having a flange-shaped head 50b and fitted to the drawing rod 50a. Consisting of As shown in FIG. 2B, in order to fix the plates 51 and 52 to each other with the blind rivet 50, the pilot holes 51a and 5
2a is formed and these are aligned. Then, the blind rivet 50 is inserted into the pilot holes 51 and 52, and the pull-out bar 50a is pulled out with a predetermined tool. Due to this drawing, the sleeve 50c is plastically deformed, and the two plate members 51, 52
Will be mutually concluded.

[0003]

However, in the fastening using the blind rivet 50, the plate members 51 and 5 are not used.
2, the pilot holes 51a and 52a need to be processed in advance. Then, a step of inserting the blind rivet 50 after processing the pilot holes 51a and 52a with high precision after processing the pilot holes 51a and 52a is required. Further, since the preparation of the pilot hole and the step of inserting the blind rivet 50 are different, there is a risk that a drill having an incorrect size may be used to form the pilot hole. If the pilot hole diameter is small, the blind rivet 50 cannot be inserted. If the hole diameter is large, there arises a problem that a specified fastening force cannot be obtained.

[0004] In view of the above circumstances, an object of the present invention is to provide a fastener with a pilot hole drilling mechanism that can simultaneously perform pilot hole processing and insertion of the fastener into a member to be fastened.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a fastener with a pilot hole drilling mechanism according to the present invention has a draw bar having a drill portion and the pull bar having a flange portion. And a diameter-enlargement drill portion for making a hole corresponding to the outer diameter of the sleeve.

[0006] With the above configuration, the drill portion of the drawn rod body is rotated by hitting the member to be fastened.
A hole is opened in the member, and a hole corresponding to the outer diameter of the sleeve is further opened by a diameter-enlargement drill portion, that is, a pilot hole is opened, and the sleeve is moved to the pilot hole with the progress of the opening of the pilot hole. It becomes possible to insert. That is, it becomes possible to simultaneously perform the preparation of the prepared hole and the insertion of the fastener into the member to be fastened.

[0007] The sleeve may be screwed to the pull-out bar so that when the pull-out bar is pulled, a deformation force is applied to the sleeve at the screwed portion. In this case, the diameter-enlargement drill portion is provided on the extraction rod body, and the diameter-enlargement drill portion hits the sleeve and separates from the extraction rod body when the extraction rod body is pulled out from the sleeve. Is good.

The pull-out rod is provided with the drill for expanding the diameter, and a rear end face of the drill for expanding the diameter is brought into contact with a front end of the sleeve, so that a deformation force is applied to the sleeve when pulling the pull-out rod. May be provided. In this case, it is preferable that the pulling rod is broken by an additional pulling force after deforming the sleeve.

[0009] The diameter-enlargement drill is screwed onto the pull-out rod, and the rear end surface of the diameter-enlargement drill comes into contact with the tip end surface of the sleeve. You may comprise so that a deformation force may be provided. In this case, it is preferable that the diameter-enlargement drill portion is detached from the extraction rod when the extraction rod is extracted from the sleeve.

[0010] The sleeve and the diameter-enlarging drill portion are integrated, a sleeve with the diameter-enlarging drill portion is screwed to the drawing bar, and the sleeve is rotated with the rotation of the drawing bar. The pulling rod may be configured so that a deformation force is applied to the sleeve at the threaded portion when the pulling rod is pulled.

In the above structure, a head having a diameter larger than the inner diameter of the sleeve may be provided on the side of the drawn rod opposite to the drill portion.

[0012]

(Embodiment 1) Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a view showing a fastener 1 with a pilot hole opening mechanism of this embodiment, and FIG. 2 is a view showing a fastening procedure using the fastener 1 with a pilot hole mechanism.

As shown in FIG. 1 (a), a fastener 1 having a pilot hole punching mechanism (hereinafter simply referred to as a fastener) includes a drawing rod (mandrel screw) 2, a sleeve 3, and a diameter-enlargement drill portion. 4 The drawing rod 2 has a drilled portion 2a with a punch at the tip and a head 2b with a diameter larger than the inner diameter of the sleeve 3 at the rear end as shown in FIGS. . At the top of the head 2b, a groove 2c (see FIG. 3E) corresponding to the tip shape of a driver (not shown) is formed. An external thread portion 2d is formed in a part of the body portion of the drawn rod 2.

As shown in FIG. 1C, a diameter-enlargement drill 4 is attached to the body between the drill 2a and the external thread 2d. The diameter-enlarging drill portion 4 is formed by arranging a plurality of fin-shaped blades on the outer periphery of the body portion, and plays a role of drilling holes corresponding to the outer diameter of the sleeve 3. Further, when the drill part 4 for diameter enlargement receives a force of a predetermined amount or more in the downward direction from the top of the figure, as shown in FIG. I have.

As shown in FIGS. 1A and 1B, the sleeve 3 has a substantially cylindrical shape, and has a flange 3a at the upper end. The sleeve 3 is made of a plastically deformable material. On the inner surface side of the lower end of the sleeve 3, a male screw portion 2 d of the drawn rod 2 is provided.
Is formed with a female screw portion 3b that is screwed into the screw hole. Pull rod 2
Is loaded into the sleeve 3 and the male screw portion 2d is screwed into the female screw portion 3b to obtain a state shown in FIG. The method of manufacturing the fastener 1 includes, for example, a head 2
A method of mounting the head 2b on the drawing rod 2 by press-fitting or the like after loading the drawing rod 2 on which no b has been mounted into the sleeve 3 may be considered.

A procedure for fastening the fastener 1 will be described with reference to FIG. First, as shown in FIG. 1A, the fastener 1 is inserted through two plates 5 and 6 to be fastened. More specifically, the drawn bar 2 is rotated by bringing the drill portion 2 a of the drawn bar 2 into contact with the plate 5. Since the drill portion 2a is rotated by the rotation of the drawing rod 2, holes are opened in the plate members 5, 6. Further, the diameter enlargement drill 4 also rotates, so that the sleeve 3
A hole corresponding to the outer diameter of the hole, that is, a pilot hole is made. Since the sleeve 3 is screwed to the drawing rod 2, it is inserted into the prepared hole as the prepared hole proceeds. In addition,
This hole can be formed by driving an electric driver (not shown) by engaging the electric driver (not shown) with the groove 2c of the head 2b of the drawing rod 2.

Next, as shown in FIG. 1B, the head 2b of the drawing rod 2 is gripped by a tool (not shown) and pulled up. At this time, the flange 3a of the sleeve 3 is pressed down. Since the sleeve 3 is screwed to the pull-out bar 2, when the pull-out bar 2 is raised, the force is received by the screwing portion, and when the sleeve 3 cannot withstand this force, the body of the sleeve 3 Is plastically deformed so as to spread to the peripheral side as shown in the figure. The plates 5 and 6 are fixed to each other by the caulking state due to the plastic deformation.

Next, as shown in FIG. 1C, the drawing rod 2 is rotated in the direction opposite to the direction in which the holes were made. The screwing state is gradually released by this reverse rotation, and the withdrawal rod 2 moves upward. Due to this upward movement, the diameter-enlargement drill portion 4 collides with the lower surface of the sleeve 3, and the diameter-enlargement drill portion 4 separates from the drawing rod body 2 by receiving the impact force of the collision.
Thereby, the draw bar 2 can be removed from the sleeve 3.

An electric drill is used to insert the fastener 1 through the plate members 5 and 6, and another special tool is used to extract the extraction rod 2, but the insertion and extraction are continuously performed. Using a tool that can be used can increase the work efficiency of fastening. It is also conceivable to discard the removed rod 2 by using a low-cost rod 2, but if the rod 2 is relatively expensive, collect and reuse it. It is desirable to do.

(Embodiment 2) Hereinafter, a second embodiment of the present invention will be described with reference to FIG. FIG. 3A is a front view showing the fastener 11 of this embodiment, FIG. 3B is a partial cross-sectional view of the fastener 11, and FIG.
It is explanatory drawing which shows the fastening state.

As shown in FIGS. 3A and 3B, the fastener 1
1 comprises a drawn rod body 12, a sleeve 13, and a drill part 14 for diameter enlargement. The drawn rod 12 has a punched drill portion 12 a at the tip and a head 12 b at the rear end having a diameter larger than the inner diameter of the sleeve 13. On the top of the head 12b,
A groove 12c corresponding to the tip shape of a driver (not shown) is formed. At a position slightly above the drill portion 12a, a diameter-enlarging drill portion 14 is formed integrally with the drawn rod body 12. The diameter-enlarging drill portion 14 has a substantially cylindrical shape having a blade portion on the lower end side, and plays a role of opening a hole corresponding to the outer diameter of the sleeve 13. The sleeve 13 has a substantially cylindrical shape, and has a flange 13a at the upper end. The sleeve 13 is made of a plastically deformable material. As a method of manufacturing the fastener 11, for example, a draw bar 12 in which a head 12b is not mounted and a diameter enlarging drill portion 14 is integrally formed is loaded into a sleeve 13 and then the draw bar 12 is attached to the draw bar 12. Part 12
A method of mounting b by press fitting or the like, or a method of mounting the drawing rod body 12 with the head 12b mounted in the sleeve 13 and then mounting the diameter enlarging drill portion 14 by press fitting or the like can be considered.

The procedure for fastening the fastener 11 will be described with reference to FIG. First, similarly to the first embodiment, the fastener 11 is inserted through the two plates 5 and 6 to be fastened. Specifically, the drill portion 12a of the drawn rod body 12 is
, And the drawn rod body 12 is rotated. Drawing rod 12
The rotation of the drill part 12a causes the plate member 5,
A hole opens in 6. Further, since the diameter-enlargement drill 14 also rotates, a hole corresponding to the outer diameter of the sleeve 13, that is, a pilot hole is formed. Then, the sleeve 13 is pushed by the head portion 12b of the drawing rod body 12, and is inserted into the prepared hole as the prepared hole proceeds.

Next, the draw bar 12 is pulled up. At this time, the flange 13a of the sleeve 13 is pressed down. Since the upper surface of the diameter-enlargement drill portion 14 comes into contact with the lower surface of the sleeve 13, when the drawing rod 12 is pulled up,
When the force is received by the contact portion and the sleeve 13 cannot withstand this force, the body of the sleeve 13 is plastically deformed so as to spread to the peripheral side as shown in the figure. The plates 5 and 6 are fixed to each other by the caulking state due to the plastic deformation. When the pull-out bar 12 is further pulled up, the body of the pull-out bar 12 cannot withstand and breaks and comes off the sleeve 13. In order to break the drawn rod 12 at a desired location, a constricted portion may be formed at the desired location.
In addition, a configuration in which the diameter-enlargement drill portion 14 is separated from the drawn rod body 12 instead of breaking the drawn rod body 12 is also conceivable.

(Embodiment 3) Hereinafter, a third embodiment of the present invention will be described with reference to FIGS. FIG. 4 is a view showing the fastener 21 of this embodiment, and FIG.
1 is a diagram showing a fastening procedure according to No. 1.

As shown in FIG. 4A, the fastener 21 is
It comprises a drawing rod (mandrel screw) 22, a sleeve 23, and a diameter-enlarging drill portion 24. The drawing rod body 22 has a punched drill portion 22a at the tip as shown in FIGS. Further, a part of the body of the drawn rod body 22 (in the vicinity of the drill part 22a) has a male screw part 22b.
Are formed. The diameter-enlarging drill portion 24 provided slightly above the drill portion 12a has a substantially cylindrical shape having a blade portion on the lower end side, and plays a role of drilling holes corresponding to the outer diameter of the sleeve 13. I have. As shown in FIG. 3D, the internal thread portion 24 is provided on the inner peripheral surface of the diameter-enlargement drill portion 24.
a is formed. This female screw portion 24a has
By screwing in the second male screw portion 22 b, the diameter-enlargement drill portion 24 is screwed to the drawing rod 22. Sleeve 23
Has a substantially cylindrical shape, and has a flange 23a at the upper end. The sleeve 23 is made of a plastically deformable material. The inner diameter of the sleeve 23 is the same as that of the male screw portion 22 of the drawn rod 2.
It corresponds to the outside diameter of b.

The procedure for fastening the fastener 1 will be described with reference to FIG. First, as shown in FIG. 1A, the fastener 21 is inserted through the two plates 5 and 6 to be fastened. here,
The rear end portion of the drawing rod body 22 is an electric rotating tool (not shown).
Are held by the chuck portion 7 of the. This chuck part 7
Can be moved forward and backward in a direction parallel to the rotation axis in addition to the rotational drive. A cylindrical pressing member 8 is provided around the chuck portion 7 of the electric rotary tool. The drawn rod 22 is rotated by bringing the drill portion 22 a of the drawn rod 22 into contact with the plate 5. The rotation of the drawing bar body 22 rotates the drill portion 22a to open holes in the plate members 5 and 6. Further, the diameter-enlarging drill portion 24 screwed to the pull-out bar 22 also rotates, so that a hole corresponding to the outer diameter of the sleeve 23, that is, a pilot hole is formed. Then, the sleeve 23 is pressed by the pressing member 8 with its flange 23a, and is inserted into the prepared hole as the preparation of the prepared hole proceeds.

Next, as shown in FIG. 2B, the chuck portion 7 is retracted upward, and the drawn bar 22 is pulled up.
At this time, the flange 23a of the sleeve 23 is
It is pressed down by. Since the upper surface of the diameter-enlarging drill portion 24 abuts against the lower surface of the sleeve 23, when the withdrawal rod 22 is raised, the force is received by the abutting portion, and when the sleeve 23 cannot withstand this force,
The body of the sleeve 23 is plastically deformed so as to spread to the peripheral side as shown in the figure. The plates 5 and 6 are fixed to each other by the caulking state due to the plastic deformation.

Next, as shown in FIG. 2C, when the pull-out bar 2 is further pulled up, the female screw 24a of the diameter-enlargement drill portion 24 cannot withstand the force, and the diameter-enlargement drill portion 24 is not allowed. Is removed from the withdrawal rod 22. As a result, the draw bar 22 can be removed from the sleeve 23.

With the fastener 21 of this embodiment, a new sleeve 23 and a diameter-enlargement drill portion 24 are mounted on the pull-out bar 22 while the pull-out bar 22 is still mounted on the chuck 7. The next fastening operation can be started. This is suitable as a form in which the drawing bar 22 is repeatedly used, and the drawing bar 22 is preferably made of tool steel.

(Embodiment 4) Hereinafter, a fourth embodiment of the present invention will be described with reference to FIGS. FIG. 6 is a view showing the fastener 31 of this embodiment, and FIG.
1 is a diagram showing a fastening procedure according to No. 1.

As shown in FIG. 6A, the fastener 31 is
It is composed of a drawing rod (mandrel screw) 32 and a sleeve 33. The drawing rod 32 has a punched drill portion 32a at the tip as shown in FIGS.
Also, a part of the body portion of the drawn rod body 32 (drill portion 32a)
) Is formed with a male screw portion 32b.

As shown in FIGS. 3 (b) and 3 (d), the sleeve 33 has a substantially cylindrical shape, and has a diameter-enlarging drill portion 33a at one end and a flange-shaped portion 33b at the other end. are doing.
The sleeve 33 is preferably made of a material whose body is plastically deformed, and the portion serving as the diameter-enlargement drill portion 33a is preferably made of a material suitable for drilling holes. Sleeve 33
The inner diameter of the body portion of the
It corresponds to the outer diameter of d. On the inner surface of the diameter-enlarging drill portion 33a of the sleeve 33, a female screw portion 33c with which the male screw portion 32b of the drawn rod 32 is screwed is formed.

The procedure for fastening the fastener 31 will be described with reference to FIG. First, as shown in FIG. 1A, the fastener 31 is inserted through the two plates 5 and 6 to be fastened. Similarly to the third embodiment, the rear end portion of the drawn rod 32 is held by the chuck 7 of an electric rotating tool (not shown). The chuck portion 7 can move forward and backward in a direction parallel to the rotation axis in addition to the rotation drive. A cylindrical pressing member 8 is provided around the chuck portion 7 of the electric rotary tool. The drawn rod 32 is rotated by bringing the drill portion 32 a of the drawn rod 32 into contact with the plate 5. Since the drill portion 32a is rotated by the rotation of the drawing bar 32, holes are opened in the plate members 5, 6. Further, the sleeve 33 (diameter-enlarged drill portion 33a) screwed to the drawing rod body 32 also rotates, and the sleeve 33 makes a hole corresponding to its outer diameter by itself, that is, while opening the prepared hole, the sleeve 33 makes a hole in this prepared hole. It is inserted.

Next, as shown in FIG. 4B, the chuck portion 7 is retracted upward, and the drawing bar 22 is pulled up.
At this time, the pressing member 8 presses the flange portion 33b of the sleeve 33.
And hold it down. When the drawing bar 32 is pulled up and the body of the sleeve 33 cannot bear the force, the body of the sleeve 33 is plastically deformed so as to spread to the peripheral side as shown in the figure. The plates 5 and 6 are fixed to each other by the caulking state due to the plastic deformation.

Next, as shown in FIG. 3 (c), when the drawing rod 2 is further pulled up, the internal thread 33c of the sleeve 33 cannot withstand the force, and the drawing rod 32 is
Depart from 3. The drawn bar 32 may be removed from the sleeve 33 by releasing the screwed state by rotating the drawn bar 32 in a direction opposite to the direction in which the holes are formed.

The fastener 31 of this embodiment is also similar to that of the third embodiment.
Similarly to the above, in a state where the drawing rod 32 is attached to the chuck 7, a new diameter-enlargement drill portion 33 is attached to the drawing rod 32.
The next fastening operation can be started by attaching the sleeve 33 with a. This is suitable as a form in which the drawing bar 32 is repeatedly used, and it is preferable that the drawing bar 32 be made of appropriate tool steel.

In the embodiment described above, the case where the plate members are fastened to each other has been described. However, the present invention is not limited to this case. For example, the case where the support member is fastened to an exterior material serving as an outer wall of a house may be employed. It can be used. If a longitudinal cut is provided in the body of the sleeve, the body of the sleeve 33 is likely to be plastically deformed.

[0038]

As described above, according to the fastener with a pilot hole punching mechanism of the present invention, a hole is opened in the member by rotating the drill portion of the drawn rod against the member to be fastened. In addition, it is possible to make a hole corresponding to the outer diameter of the sleeve by the diameter-enlargement drill portion, that is, a hole is made, and the sleeve can be inserted into the hole as the hole is made. Become. That is, there is an effect that the preparation of the prepared hole and the insertion of the fastener can be simultaneously performed on the member to be fastened.

[Brief description of the drawings]

FIG. 1A is a front view showing a fastener with a pilot hole punching mechanism according to a first embodiment, FIG. 1B is a cross-sectional view of a sleeve, and FIG. (D) is a front view of the drawn rod in a state where the diameter-enlargement drill portion is detached, and (e) is a plan view showing the head of the drawn rod.

FIG. 2 (a) is an explanatory view showing a state in which a fastener with a pilot hole punching mechanism is inserted, and FIG. 2 (b) is an explanatory view showing a state in which a withdrawal rod is pulled up; FIG. 7C is an explanatory view showing a state where the drawing bar is removed from the sleeve.

FIG. 3A is a front view showing a fastener with a pilot hole punching mechanism according to the second embodiment, and FIG. 3B is a view showing a state of external fitting of a sleeve, and FIG. (c) is an explanatory view of a state in which the drawn bar is removed from the swaged sleeve.

FIG. 4 (a) is a front view showing a fastener with a pilot hole punching mechanism according to a third embodiment, and FIG. 4 (b) is a view showing a state of external fitting of a sleeve and a diameter enlarging drill portion. (C) is a front view of the drawn rod, and (d) is a cross-sectional view of the sleeve and the diameter-enlargement drill portion.

FIG. 5 (a) is an explanatory view showing a state in which a fastener with a pilot hole punching mechanism is inserted, and FIG. 5 (b) is an explanatory view showing a state in which a withdrawal rod is pulled up; FIG. 7C is an explanatory view showing a state where the drawing bar is removed from the sleeve.

FIG. 6 (a) is a front view showing a fastener with a pilot hole punching mechanism according to a fourth embodiment, and FIG. 6 (b) shows a state of externally fitting a sleeve with a diameter-enlargement drill portion. FIG. 4C is a front view of the drawn rod, and FIG. 4D is a cross-sectional view of a sleeve with a diameter-enlargement drill.

FIG. 7 (a) is an explanatory view showing a state in which a fastener with a pilot hole punching mechanism is inserted, and FIG. 7 (b) is an explanatory view showing a state in which a withdrawal rod is pulled up; FIG. 7C is an explanatory view showing a state where the drawing bar is removed from the sleeve.

FIG. 8 (a) is a partial cross-sectional view of a blind rivet, and FIG. 8 (b) is a cross-sectional view showing fastening using a blind rivet.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fastener with pilot hole mechanism 2 Pull-out bar 2a Drill part 3 Sleeve 3a Flange part 4 Drill part for diameter enlargement 11 Fastener with pilot hole punch mechanism 12 Pull-out rod body 12a Drill part 13 Sleeve 13a Collar part 14 Diameter Drilling part for enlargement 21 Fastener with pre-drilling mechanism 22 Pull-out bar 22a Drill part 23 Sleeve 23a Flange part 24 Drill part for diameter expansion 31 Fastening tool with pre-drilling mechanism 32 Pull-out rod 32a Drill part 33 Sleeve 33a diameter Enlarged drill 33a flange

Claims (9)

[Claims] 1. A drawn rod body having a drill portion, a sleeve having a flange-shaped portion, which is externally fitted to the drawn rod body, and a diameter expanding drill portion for forming a hole corresponding to the outer diameter of the sleeve. A fastener with a pilot hole opening mechanism. 2. The sleeve is screwed onto the drawing rod,
The fastener with a pilot hole opening mechanism according to claim 1, wherein a deformation force is applied to the sleeve at the threaded portion when the pull-out bar is pulled. 3. The pull-out rod body is provided with the diameter-enlargement drill portion, and when the pull-out rod body is pulled out of the sleeve, the diameter-enlargement drill portion hits the sleeve and separates from the pull-out rod body. 3. The fastener with a pilot hole punching mechanism according to claim 2, wherein: 4. The pull-out rod body is provided with the diameter-enlargement drill portion, and a rear end surface of the diameter-enlargement drill portion is in contact with a tip end surface of the sleeve, so that the pull-out rod body is attached to the sleeve when the pull-out rod body is pulled. The fastener with a pilot hole punching mechanism according to claim 1, wherein a deformation force is applied. 5. The fastener with a pilot hole opening mechanism according to claim 4, wherein the pull-out bar is broken by an additional pulling force after the sleeve is deformed. 6. The pull-out rod body is screwed onto the pull-out rod body, and the rear end face of the diameter-enlargement drill section comes into contact with the front end face of the sleeve, so that the pull-out rod body is pulled. The fastener according to claim 1, wherein a deformation force is applied to the sleeve. 7. A pilot hole drilling mechanism according to claim 6, wherein said diameter-enlarging drill portion is detached from said extraction rod when said extraction rod is pulled out of said sleeve. Fasteners. 8. The sleeve and the diameter-enlargement drill portion are integrated, a sleeve with the diameter-enlargement drill portion is screwed onto the drawing rod, and the sleeve is rotated with the rotation of the extraction rod. The fastening tool with a pilot hole punching mechanism according to claim 1, wherein a deforming force is applied to the sleeve at the threaded portion when the pulling rod is pulled. 9. The pilot hole according to claim 1, wherein a head having a diameter larger than the inner diameter of the sleeve is provided on a side of the drawing bar opposite to a drill portion. Fastener with opening mechanism.