JP2815368B2 - Chamfering blade for rotary drilling tools - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method of manufacturing a rotary drilling tool such as a drill, a reamer or a burnishing drill.
The present invention relates to a chamfering blade of a rotary drilling tool used to form a recess having an inner diameter larger than the inner diameter.

[Prior Art] Conventionally, as this kind of cutting tool, there has been a countersunk screw milling cutter for forming, for example, a recess for sinking a countersunk screw at the opening edge of a hole. This milling cutter has a shank on the base end side, and the shank is used by being engaged with a chuck such as a drilling machine in the same manner as a shank of a drill.

For example, when drilling a workpiece such as a work and forming a recess for sinking a flat head screw using a single drilling machine, a drill is first attached to the drilling machine, and a hole is drilled by the drill. Subsequently, the drill is removed and the milling cutter is attached. Then, while rotating the milling cutter, the milling cutter was brought into contact with the opening edge of the drilled hole, thereby forming a sinking recess of the flathead screw.

[Problems to be Solved by the Invention] Therefore, in order to form a hole at the opening edge of the hole with the milling cutter while using a single drilling machine to drill a hole or the like, it is necessary to use a drill with respect to the drilling machine. The milling cutter must be replaced, and the cutting work is interrupted due to the replacement work, resulting in a problem that the working efficiency is reduced. For this reason, it has been desired to provide a cutting tool capable of forming a recess at the opening edge of the hole at the same time as drilling work with a drill or the like.

An object of the present invention is to attach and use a rotary drilling tool such as a conventional drill, reamer, or burnishing drill, and at the same time to perform a drilling or the like with the drilling tool, to form a recess at the opening edge of the hole. An object of the present invention is to provide a chamfering blade for a rotary drilling tool, which can form a chamfering blade for a rotary drilling tool, which can be easily attached to the rotary drilling tool.

[Means for Solving the Problems] In order to achieve the above object, the chamfering blade of the rotary drilling tool of the present invention is attached to a rotary drilling tool (5) having a plurality of grooves formed therein. A chamfering blade for forming a recess (Ha) having an inner diameter larger than the inner diameter of the hole (H) formed in the work (W) by the drilling tool at the opening edge of the hole (H); A body (1) having an engagement surface (18) for engaging with a wall surface (53a) of one groove (53) of a tool.
And a front side surface (22) connected to an engaging surface (24) for engaging with a wall surface (51b) of another groove (51) of the drilling tool, and the front surface (22) is formed to be in contact with the main body. Fixing plate (2) having side wall (25) projecting toward the front side
A cutting blade (11a) formed at a tip of at least one of the main body and the fixing plate; and a connecting tool (3) for connecting the main body and the fixing plate. An insertion hole (42) is formed in the side wall of the fixing plate, and a mounting recess (41) is formed in the main body so that the tool can be inserted substantially in the direction toward the center of the drilling tool. When the connecting tool is inserted into the hole and the mounting recess to connect the main body and the fixing plate, the wall surface of each groove of the drilling tool is formed by the engaging surface of the main body and the engaging surface of the fixing plate. (51b, 53a) can be fixed to the outer peripheral portion of the drilling tool by pinching.

Further, in the chamfering blade of the present invention, the connecting tool is a screw (3), the mounting recess formed in the main body is a screw hole (41), and the screw is screwed into the screw hole. It is preferable that the side wall of the fixing plate is sandwiched between the head of the screw and the main body.

[Operation] In attaching the chamfering blade of the present invention to the drilling tool, the engaging surface of the main body is engaged with the wall surface of one groove of the drilling tool, and the engaging surface connected to the front side surface of the fixing plate is fixed. While engaging the wall surface of another groove of the drilling tool, the side wall of the fixing plate is brought into contact with the main body, and in this state, the mounting recess formed in the main body and the insertion hole formed in the side wall of the fixing plate are formed. After matching, the connecting tool is inserted into these insertion holes and mounting recesses to connect the main body and the fixing plate to each other. At the time of this connection, the engaging surface of the main body and the engaging surface of the fixed plate press the wall surfaces of the grooves of the drilling tool. By this pinching action, the chamfering blade of the present invention is securely fixed to the outer peripheral portion of the drilling tool.

In the present invention, the insertion hole of the fixing plate side wall and the mounting recess of the main body are arranged such that when the side wall of the fixing plate and the main body are brought into contact with each other so that the insertion hole and the mounting recess coincide with each other, the connecting tool is substantially at the center of the drilling tool. It is formed so that it can be inserted in the direction toward it. That is, the direction of insertion of the connecting tool into the insertion hole and the mounting recess is oriented substantially at the center of the drilling tool. For this reason, when attaching the chamfering blade of the present invention to the drilling tool previously attached to a drilling machine or the like, the drilling tool is rotated based on the force when the connecting tool is pushed into the insertion hole and the mounting recess. It is difficult for a moment to be generated. Therefore, when attaching the chamfering blade to the drilling tool attached to a drilling machine, etc., the drilling tool is fixed using a special fixing tool to prevent inadvertent rotation of the drilling tool. You do n’t have to
Installation work of the chamfer blade is extremely easy.

In addition, the connecting member is formed of a screw, and the mounting recess of the main body is formed as a screw hole. By screwing the screw into the screw hole, the side wall of the fixing plate is strongly inserted between the head of the screw and the main body. It is possible to sandwich the main body and the fixing plate, and it is possible to strengthen the interconnection between the main body and the fixing plate, and to increase the pressing force of each engagement surface of the main body and the fixing plate against the wall surface of each groove of the drilling tool. it can.

The drilling tool and the chamfer blade attached thereto are integrally rotated by a drilling machine or the like. For this reason, following the drilling of the workpiece by the drilling tool, the cutting edge of the chamfering blade is brought into contact with the workpiece, so that the concave portion having an inner diameter larger than the inner diameter of the hole is formed at the opening edge of the hole drilled by the drilling tool. Locations can be formed continuously.

Embodiment An embodiment of a chamfering blade of a rotary drilling tool will be described below with reference to FIGS.

As shown in FIG. 1, each of the pair of chamfer blades has a main body.
1, a fixing plate 2 and a screw 3 as a connecting tool between the two, and by their cooperation, it can be attached to a drilling tool (burnishing drill 5 in this embodiment).

As can be seen from FIGS. 1 and 2, each main body 1 is made of a member whose longitudinal direction is the direction of the central axis L of the burnishing drill 5 to which it is attached. A first side surface 12, a second side surface 13, a third side surface 14, and a third side surface of the outside of the main body 1 are sequentially adjacent to a front side surface 11 of the burnishing drill 5 in the cutting rotation direction X.
A rear side surface 15 adjacent to 14 is formed, and further this rear side surface 15
The fourth side face 16 and the fifth side face 17,
A sixth side surface 18 and a seventh side surface 19 are formed. The seventh side surface 19 is connected to the front side surface 11, and the side surface of the main body 1 is composed of nine surfaces in total.

The fourth to sixth side surfaces 16 to 18 are engagement surfaces with the outer peripheral portion of the burnishing drill 5, and are formed in a planar concave shape as a whole. The angle formed by the fourth side face 16 and the fifth side face 17 is obtuse, and the fifth side face 17 and the sixth side face 18 are further formed.
Is formed to be an acute angle, and the sixth angle
The portion surrounded by the side surface 18, the seventh side surface 19, and the front side surface 11 is formed so as to form an engagement ridge extending over the entire length of the main body 1.

Further, as can be seen from FIG.
1a, when the main body 1 is attached to the burnishing drill 5,
A conical inclined surface 10 converging downward is formed. The oblique curved surface 10 includes a front side surface 11, a first side surface 12, and a second side surface.
13, connected to the leading edge of the third side surface 14 and the rear side surface 15,
Moreover, a cutting edge 11 is provided at the tip edge of the front side surface 11 which is connected to the inclined curved surface 10.
a is formed. In addition, a pair of chamfering blades
It is attached to the burnishing drill 5 so that the height of 1a becomes equal.

As shown in FIG. 1, the fixing plate 2 has a rear side surface 21 and a front side surface 22. An engagement surface 24 for engaging the fixed plate 2 with the burnishing drill 5 is formed on the front side surface 22 of the fixed plate 2 over the entire length of the fixed plate 2 in the longitudinal direction. The front side surface 22 is formed so that the front side surface 22 is engaged with the main body 1 and a gap is partially formed between the front side surface 22 and the main body 1 even when the engaging surface 24 is engaged with the burnishing drill 5. Have been.

In the chamfering blade shown in FIG. 1, a side wall 25 is formed so as to protrude from the outer end of the fixed plate 2 toward the front side surface 22 over the entire length of the fixed plate 2.
Was made substantially L-shaped in cross section. And this side wall 25
The fixing plate 2 has two insertion holes 42 through which the screws 3 are inserted. On the other hand, two screw holes 41 of the main body 1 are formed on the third side surface 14 so as to be aligned in the longitudinal direction.

By the way, as can be seen in FIG. 1, the burnishing drill 5 to which the above-mentioned chamfering blade is attached has two drill grooves 51 facing the outer periphery of a cylindrical shaft main body connected to a shank (not shown) as chip guide grooves, and A total of four reamer grooves 53, 55 facing each other in a pair are provided, and a first land 52 is provided between the drill groove 51 and the first reamer groove 53 so that the first reamer groove 53 and the second reamer groove 55 are formed. A second land 54 is provided between them,
The third between the second reaming groove 55 and the other drill groove 51
A land 56 is provided. Furthermore, a conical head is provided at the tip of the burnishing drill 5, and a cutting blade (not shown) is formed at the tip of the front side surface 51a in the cutting rotation direction X of the drill groove 51 from the head. . The drill groove 51, the first reamer groove 53 and the second reamer groove 55 are linear grooves.

Each of the main body 1, the fixing plate 2, and the screw 3 are attached to the burnishing drill 5 in the following manner.

When attaching the main body 1 and the fixing plate 2 to the burnishing drill 5, first, the sixth side surface 18 of the main body 1 is engaged with the front side surface 53 a of the first reamer groove 53 of the burnishing drill 5, and the outer peripheral surface of the second land 54. Then, the fifth side surface 17 is engaged, and the fourth side surface 16 is engaged with the outer peripheral surface of the third land 56.

In this state, the inner side surface of the side wall 25 of the fixing plate 2 is formed by two screw holes 41 as two mounting recesses provided on the third side surface 14 of the main body 1 and two screw holes 41 provided on the side wall 25 of the fixing plate 2. The insertion holes 42, which are through holes, are engaged with the third side surface 14 of the main body 1 so as to correspond thereto, and the engagement surface 24 of the fixed plate 2 is engaged with the rear side surface 51b of the drill groove 51 of the burnishing drill 5. . Note that there is a gap between the inner side surface of the side wall 25 and the third side surface 14 of the main body 1 and between the engaging surface 24 of the fixed plate 2 and the rear side surface 51b of the burnishing drill 5 even after the engagement.

In this way, when the screw 3 is screwed into the screw hole 41 of the main body 1 from the outer surface side of the side wall 25 of the fixing plate 2, the third side surface 14 of the main body 1 and the inner side surface of the side wall 25 of the fixing plate 2
In addition, the rear side surface 15 of the main body 1 and the front side surface 22 of the fixing plate 2 try to come into close contact with each other.

Accordingly, the sixth side surface 18 as the engaging surface of the main body 1 gradually presses the front side surface 53a of the first reamer groove 53, and the engaging surface 24 of the fixing plate 2 also moves to the rear side surface 51 of the drill groove 51.
In order to gradually press b, the body 1, the fixing plate 2 and the screw 3 constituting the chamfering blade are integrally bitten by the burnishing drill 5. In addition, the opening of the drill groove 51 of the burnishing drill 5 can be attached even if the chamfer blade is attached.
As before installation, it is in a fully opened state.

By configuring the chamfering blade in this manner, the force with which the screw 3 is pushed when the screw 3 is screwed into the fourth side of the main body 1
16 is transmitted to the burnishing drill 5 as a force for pressing the third land 56 of the burnishing drill 5. In addition, since the direction of the force is substantially the direction passing through the central axis L of the burnishing drill 5, a moment enough to rotate the burnishing drill 5 attached to a drilling machine or the like hardly occurs. Therefore, in the present configuration, even when the work of attaching the chamfering blade is performed while the burnishing drill 5 is attached to a drilling machine or the like, the work is easy to perform without turning without particularly fixing the burnishing drill 5. There are advantages.

Now, burnishing drill 5 with the chamfering blade attached
Is engaged with a chuck (not shown) such as a drilling machine, and the tip of the burnishing drill 5 is brought into contact with a workpiece such as a workpiece while rotating the burnishing drill 5 in the cutting rotation direction X. Then, a hole H is formed in the work W by the burnishing drill 5 as shown in FIG. At this time, cutting chips are discharged from the drill groove 51 of the burnishing drill 5, but since the chamfering blade is attached to the burnishing drill 5 as described above,
The chamfering blade does not hinder the discharge of cutting chips, and the drilling operation by the burnishing drill 5 can be performed smoothly.

When the burnishing drill 5 is further advanced, the cutting edge 11a of the main body 1 of the double-sided cutting blade contacts the opening edge of the hole H formed by the burnishing drill 5. By this cutting edge 11a, an inverted truncated cone-shaped recess Ha having an inner diameter larger than the inner diameter of the hole H can be formed at the opening edge of the hole H. At this time, the double-sided cutting blade is securely positioned with respect to the burnishing drill 5, and is reliably rotated integrally with the burnishing drill 5, so that the work W can be reliably processed by the cutting blade 11a of the main body 1. it can.

After the drilling operation, to remove each chamfering blade from the burnishing drill 5, the screw 3 of the chamfering blade may be loosened and then pulled out to the tip side of the burnishing drill 5. Further, even when the depth of the hole formed by the burnishing drill 5 is different each time, the mounting position of the chamfering blade can be moved up and down (in the direction of the central axis L) according to this depth.

As described above, the chamfering blade of the present embodiment can be easily attached to the burnishing drill 5 and used, and the recess H is formed at the opening edge of the hole H following the drilling or finishing of the inner surface of the hole by the burnishing drill 5. Since it is not necessary to change tools, a series of machining operations can be efficiently performed.

In the above embodiment, a pair of chamfering blades is attached to the burnishing drill 5, but it is also possible to attach only one of them.

In the above embodiment, as the drilling tool, the burnishing drill 5 having the linear drill groove 51 and the reamer grooves 53 and 55 has been described. If the engaging portion of the chamfering blade is formed corresponding to the above, the chamfering blade can be attached using the drill groove.

[Effects of the Invention] The chamfering blade of the rotary drilling tool of the present invention has the following excellent effects.

Since the wall surfaces of the grooves of the drilling tool are pressed by the engaging surfaces formed on the main body and the fixing plate, the chamfering blade can be securely attached to the drilling tool by using the grooves.

Subsequent to the drilling of the workpiece by the drilling tool, the cutting edge of the chamfering blade is brought into contact with the workpiece to form a recess with an inner diameter larger than the inner diameter of the hole at the opening edge of the hole made by the drilling tool. It can be formed continuously. In this case, depending on the depth of the hole drilled by the drilling tool,
The mounting position of the chamfering blade in the longitudinal direction of the drilling tool can be freely set, and the drilling and the recess formation can be a series of operations.

The insertion hole in the side wall of the fixed plate and the mounting recess in the main body are
Since the insertion direction of the connecting tool for these is formed so as to be directed substantially toward the center of the drilling tool, when the chamfering blade is later attached to the drilling tool previously mounted on a drilling machine or the like, the connecting tool is inserted. A moment for rotating the drilling tool based on the force when the drilling tool is pushed into the insertion hole and the mounting recess is less likely to be generated. For this reason, it is not necessary to worry about careless rotation of the drilling tool, and attachment of the chamfering blade to the drilling tool becomes extremely easy.

In the case where the connecting member is formed of a screw and the mounting recess of the main body is formed of a screw hole, the screw is screwed into the screw hole so that the side wall of the fixing plate can be strongly sandwiched between the head of the screw and the main body. it can. Therefore, the interconnection between the main body and the fixing plate can be strengthened, and the pressing force of each engagement surface of the main body and the fixing plate against the wall surface of each groove of the drilling tool can be increased. The attachment of the chamfering blade to the drilling tool can be made more reliable.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a state in which a chamfering blade according to an embodiment of the present invention is mounted on a burnishing drill.
The figure is a front view for explaining the outline of the working state. DESCRIPTION OF SYMBOLS 1 ... Body, 2 ... Fixing plate, 3 ... Screw as a connecting tool, 5 ... Burnishing drill as a rotary drilling tool, 11a ... Cutting edge, 18 ... No. as an engaging surface of the body 6
Side surface, 22: Front surface of fixed plate, 24: Engagement surface of fixed plate, 25: Side wall of fixed plate, 41: Screw hole as mounting recess formed in main body, 42: Formed on side wall Inserted hole, 51 ... Chip guide groove of drilling tool, 51b ...
… Wall surface of the chip guide groove, 53 …… reamer groove of the drilling tool, 53
a: Wall surface of reamer groove, H: Hole, Ha: Concavity, L:
... Center axis of drilling tool, W ... Work, X ... Cutting rotation direction.

Claims (2)

(57) [Claims] 1. A rotary drilling tool (5) having a plurality of grooves (51, 53) formed therein, and a hole (H) drilled in a workpiece (W) by the drilling tool (5). A chamfering blade for forming a recess (Ha) having an inner diameter larger than the inner diameter of the hole (H) in the opening green of the hole (H), the wall (53a) of one groove (53) of the drilling tool (5). )
Main body (1) formed with an engaging surface (18) for engaging with the engaging surface, and an engaging surface for engaging with a wall surface (51b) of another groove (51) of the drilling tool (5). A fixing plate (2) having a front surface (22) connected to the (24), and having a side wall (25) protruding toward the front surface (22) so as to contact the main body (1); A cutting blade (11a) formed at the tip of at least one of the main body (1) and the fixing plate (2), and a connection for connecting the main body (1) and the fixing plate (2); And a through hole (25) of the fixing plate (2) so that the connecting tool (3) can be inserted in a direction substantially toward the center of the drilling tool (5). 42), and a mounting recess (41) is formed in the main body (1), and these insertion holes (42) and mounting recesses (41) are formed. When the main body (1) and the fixing plate (2) are connected to each other by inserting the connecting tool (3) into the connector, the engagement surface (18) of the main body (1) and the fixing plate (2) are connected. The wall surface (51b, 53a) of each groove (51, 53) of the drilling tool (5) is pinched by the engagement surface (24) and can be fixed to the outer peripheral portion of the drilling tool (5). A chamfering blade for a rotary drilling tool. 2. The connecting tool is a screw (3), the mounting recess formed in the main body (1) is a screw hole (41), and the screw (3) is screwed into the screw hole (41). The side wall (25) of the fixing plate (2) is inserted between the head of the screw (3) and the main body (1) by being inserted. Chamfering blade for rotary drilling tools.