JP2001038508A - Boring bar supporter and inner diameter machining tool using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and quickly provide a knife edge height precision when exchanging a boring bar in regard to a boring bar supporter fixing and inserting the boring bar provided with a detent face on a side face into a shank insertion hole. SOLUTION: A wedge shaped pressurizing body 51 is attached to one side of a shank insertion hole 12, the wedge shaped pressurizing body 51 is wedged in by a screw mechanism, and a detent face M of a shank S is pressed by a wedge action. Because this detent face M is pressurized by the wedge action of the wedge shaped pressurizing body 51, fixing force is large, and consequently, it is difficult for the shank S to rotate around the axis. Thus, a deviation of a knife edge height is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boring bar holder for holding a shank of a boring bar, and an inner diameter machining tool using the same.

[0002]

2. Description of the Related Art Conventionally, a boring bar (also referred to as a holder) used for boring (boring) processing, which has a relatively small inner diameter, is disclosed in Japanese Utility Model Application Laid-Open No.
JP-A-67002, JP-A-1-234104
And the technology described in Japanese Patent Publication No. In order to ensure the rigidity of the boring bar and the optimal protrusion of the bar, these shank (shaft) is attached to a dedicated boring bar holder (also called a sleeve, holding part or adapter). It is inserted, fixed, and fixed to a tool rest of a machine tool such as an NC automatic lathe or lathe via the boring bar holder.

Such a boring bar holder has a shank insertion hole formed in a straight circular cross section so that a shank of a boring bar formed by clamping a tip for processing an inner diameter at a tip thereof can be freely inserted and removed. Have. And about two screw holes penetrated in a direction substantially perpendicular to the axial direction, the shank is inserted into the shank insertion hole to a position where the amount of protrusion according to the processing conditions is reached, and a set screw ( It is configured so that it can be fixed by screwing and tightening a hexagon socket set screw.

A boring bar (hereinafter, also simply referred to as a bar) used for such small-diameter inner diameter processing (hereinafter, also simply referred to as processing) is liable to break or break during processing because of its small diameter. It was like. That is, the boring bar holder is once removed from the tool rest. Then, the two setscrews holding the boring bar are loosened and the bar is pulled out of the holder. Next, a new boring bar having a cutting edge and a throw-away tip is inserted into the shank insertion hole of the boring bar holder and fixed as described above. Then, the inner diameter machining tool set in this way is fixed to the tool rest so as to be the same as the initial setting, and the inner diameter machining is continued.

Since the shank insertion hole (hereinafter, also simply referred to as an insertion hole) is usually a hole having a circular cross section, the boring bar can rotate in the shank insertion hole when the set screw is tightened. For this reason, when the boring bar is replaced, simply tightening the set screw may cause a deviation in the height (position) of the cutting edge of the insert.

In order to avoid such a problem, a conventional boring bar cuts a side surface of a shank (for example, a side surface corresponding to a rake surface side of a cutting tip and a side surface (parallel) opposed thereto) in parallel to an axis. It is normal to make it a flat surface and use this as a detent surface. That is, insert the boring bar into the shank insertion hole of the boring bar holder, screw in the set screw so that the detent surface is located on the screw hole side of the side surface, and tighten the detent surface at the tip to tighten the boring bar. Is fixed. Such fixation restricts the rotation of the boring bar in the shank insertion hole, which helps to prevent the height of the cutting edge of the insert from being changed when the boring bar is replaced.

[0007]

However, even if a detent surface is provided on the side surface of the shank of the boring bar, the shank is still rotatable in the shank insertion hole before the set screw is tightened. Absent. Further, at the time of tightening the set screw, the axis of the set screw and the detent surface thereof are not always correctly perpendicular to be tightened. That is,
Even if the axis of the set screw is not perpendicular to the detent surface, the set screw can be tightened and fixed in that state. Therefore, even if a detent surface is provided on the side surface of the shank, the replacement of the boring bar is not completed simply by simply inserting the boring bar and tightening the set screw. In other words, it is necessary to use a setting gauge or to perform trial machining while measuring the height of the cutting edge of the insert, and to obtain the positional accuracy of the cutting edge while adjusting the height.

In particular, when performing trial processing,
The boring bar holder must be removed from the tool post, the set screw must be loosened, and the shank must be rotated through a small angle to compensate for the blade height. As described above, in the conventional boring bar holder, there is a problem in the setup such that replacement of the boring bar due to damage or the like is troublesome and time-consuming.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and when replacing a boring bar holder, a boring bar holder which can easily and quickly obtain the height accuracy of its cutting edge and a boring bar holder. It is an object of the present invention to provide an inner diameter machining tool used.

[0010]

According to the first aspect of the present invention, there is provided a boring bar holding body according to the present invention, wherein a boring bar having a detent surface on a side surface of the shank is insertable. In a boring bar holder having an insertion hole, on one side of the shank insertion hole,
A wedge-shaped pressing body is mounted, and the wedge-shaped pressing body is pressed by a pressing means by a screw mechanism, whereby the detent surface of the shank is pressed by a wedge action.

According to the boring bar holder having such a configuration, the locking surface of the shank can be pressed by the wedge action of the wedge-shaped pressing member. Moreover, stable fixation can be obtained. Accordingly, when the shank is replaced, it is easier to prevent the height of the cutting edge from being changed due to the rotation around the axis.

In the above means, the pushing direction of the wedge-shaped pressing body may be substantially the same as the axial direction of the shank insertion hole. In the boring bar holding body of the present invention, it is sufficient that the detent surface can be pressed by the wedge-shaped pressing body. Therefore, the pushing direction of the wedge-shaped pressing body may be appropriately designed, but is preferably substantially the same as the axial direction of the shank insertion hole.

In this case, it is preferable that the wedge-shaped pressing member is pushed from the front end to the rear end of the shank insertion hole. In the present invention, the front end side means an end face side close to the cutting edge, and the rear end side is an end face side opposite thereto. This is because the boring bar is fixed by the wedge-shaped pressing body at the position closest to the cutting edge, so that the clamping strength (performance) is improved. Further, in any of the above means, the screw mechanism is provided with a screw hole for forming a reverse screw on the boring bar holding member and the wedge-shaped pressing member with the pushing direction of the wedge-shaped pressing member as an axis, It is preferable that a screw member having a screw to be screwed into each hole is screwed into each screw hole.

The boring bar according to the present invention is characterized in that a boring bar having a detent surface on the side surface of the shank is inserted into the shank insertion hole of any of the above-mentioned boring bar holders, and the detent surface is pressed by the wedge. The rotation preventing surface of the shank is pressed by a wedge action by being inserted opposite to the body and being pushed in by the pushing means by a screw mechanism.

[0015]

1 to 5 show an embodiment of the present invention.
This will be described in detail with reference to FIG. FIG. 1 is a front view of a boring bar holder 11 according to the present invention, FIG. 2 is an enlarged longitudinal sectional view of a main part of FIG. 1, and FIG.
It is a perspective view of. This boring bar holder 11 is
It has a substantially rectangular cylindrical shape (rod shape) having a shank insertion hole 12 having a circular cross section in the longitudinal direction, and has a front end face 13 side (FIG.
2 left) is provided with a wide portion 15 which is wide in the left and right directions in plan view. Then, the front end 1 of the shank insertion hole 12
3, a cutout portion 20 cut in parallel in a plan view so as to open on the upper surface 16 of the wide portion 15 is formed on the upper side of the opening portion 3, and a depth portion of the cutout portion 20 (FIG. 2
The right side) is a wall surface 23 perpendicular to the axis (axis) G1 of the insertion hole 12.
Are formed. The upper surface 26 of the narrow portion 25 that is narrower than the wide portion 15 penetrates vertically toward the axis G1 of the shank insertion hole 12 at the center in the width direction at a position slightly closer to the front end 13 than the center in the longitudinal direction. A screw hole 27 is provided. In this example, the portion near the rear end of the shank insertion hole 12 is a through hole 12a having a slightly larger diameter.

In the present embodiment, a plate member 31 having a rectangular shape in a plan view is fixed to the upper surface 16 of the wide portion 15 with a screw member 41, and the plate member 31 is provided on the side of the insertion hole 12 corresponding to the notch 20. The surface is an inclined surface 33 that linearly descends at a fixed angle from the front end 13 to the rear end 17. However, the width W of the inclined surface 33 is the same as the width of the notch 20. A groove 19 having a square cross section is formed between the narrow portion 25 and the upper surface 16 of the wide portion 15 so as to cross the upper surface 16, and is provided on the lower surface of the rear end side of the plate 31. The protruding portion 34 is fitted. Further, such a plate material 31 is fixed by screwing a bolt 41 into a screw hole 29 provided downward on the upper surface 16 of the wide portion 15 from a through hole 35 provided at a symmetric position on both sides in plan view. I have.

A wedge-shaped pressing body (piece) 51 having a vertically wedge-like shape is mounted on the notch 20 as follows. In addition, the wall surface 23 at the back of the notch 20 has an axis G2 which is in a virtual plane including the axis G1 of the shank insertion hole 12 and is parallel to the inclined surface 33 of the fixed plate member 31, that is, the angle of inclination is substantially the same as the inclined angle. Screw hole 2 with
4 are provided at a predetermined depth.

On the other hand, the wedge-shaped pressing body 51 is
2 has a constant thickness 僅 か slightly smaller than the width in plan view, and has a wedge-like shape in which the vertical interval decreases toward the right in FIG. That is, in FIG. 2, the lower surface 55 is a flat surface parallel to the axis G <b> 1 and the upper surface 53 is an inclined surface inclined at the same inclination as the inclined surface 33 of the plate 31. By being pushed in the right direction, the flat surface (lower surface) 55 is moved by the wedge action of the two inclined surfaces so that the axis G of the insertion hole 12 is formed.
1. In the present embodiment, the front end face 57 of the wedge-shaped pressing body 51 is substantially the same as the front end face 13 of the holding body 11, so that the flat face 55 of the shank S of the boring bar 201 inserted into the shank insertion hole 12. The wedge-shaped pressing body 51 is set so as to abut against the detent surface (plane) M. At this time, the rear end face 58 of the wedge-shaped pressing body 51 does not abut on the wall surface 23 of the notch 20, that is, the interval is maintained. It is formed as follows.

Next, the screw mechanism will be described. In the present embodiment, the thickness (left and right in plan view) of the wedge-shaped pressing body 51 is the center in the Т direction, and the upper surface (inclined surface) 53 is the inclined surface 3 of the plate material 31.
3, a screw hole 59 is provided so as to penetrate so as to form the same axis as the axis G <b> 2 of the screw hole 24 provided in the wall surface 23 of the notch 20. However, in this embodiment, the screw hole 24 of the wall surface 23 is a right-hand screw,
The screw hole 59 of the wedge-shaped pressing body 51 is a left-handed screw, and in the state of FIG. 2, a straight screw member 61 with a hexagonal hole provided with screws to be screwed into the two screw holes 24 and 59, respectively.
Are set so as to be screwed into the respective screw holes 24 and 59. In this embodiment, the angle of inclination of the inclined surface 33 and the axis of the reverse screw with respect to the axis G1 of the shank insertion hole 12 is 1 in the present embodiment.
Although the angle is set to 0 degree, the angle is appropriately in the range of 5 to 15 degrees.

In the boring bar holder 11 of the present embodiment, for example, as shown in FIG. 5, the boring bar 2 with the throw-away tip C forming a cutting edge is mounted.
The shank S of No. 01 is inserted into the shank insertion hole 12 so as to have a desired protruding amount, so that the detent surface M thereof is on the flat surface 55 side of the wedge-shaped pressing body 51. And
Under this condition, a hexagonal wrench is inserted into the hexagonal hole at the outer end of the reverse screw member 61, and when turned clockwise, the right screw screwed into the wall surface 23 advances into the screw hole 24 ( At the same time, the wedge-shaped pressing body 51 is drawn along the inclined surface 33 on the wall surface 23 side by the reverse screw, and the rotation is restricted by the opposing surface 21 of the cutout portion 20 so as to be drawn toward the rear end side. The shaft G1 of the shank insertion hole 12
Move closer to the direction. As a result, the flat surface 55 of the wedge-shaped pressing body 51 is
Abuts against the detent surface M.

Thereafter, when the screw member 61 is further screwed in, the flat surface 55 strongly presses the detent surface M by wedge action. Thus, even when the flat surface 55 of the wedge-shaped pressing body 51 and the detent surface M of the shank S are not parallel at the time of contact, the detent surface M comes into close contact with the flat surface 55 due to the pressing by the wedge action. Even if the both surfaces have a slight inclination about the axis G1, the boring bar 201 is automatically rotated and fixed by the minute angle by the pressing by the same wedge action. In addition, in the boring bar holding body 11 of the present embodiment, in addition to the fixing by the wedge-shaped pressing body 51, the set screw 28 is screwed into the screw hole 27 of the upper surface 26, so that the boring bar 201 is inserted into the boring bar holding body 11. The set ends. Accordingly, thereafter, as in the related art, the tool is used by fixing it to a tool rest (not shown) as an inner diameter machining tool set as described above.

Then, during the processing, the boring bar 2
When the 01 is broken and replaced, the boring bar holder 11 is removed from the tool post, the screw member 61 fixing the set screw 28 and the wedge-shaped pressing body 51 is loosened, and the broken bar 201 is extracted. When a new boring bar is set in the same manner as described above, unlike the case of fixing with a conventional set screw, the same cutting edge height as before the fracture can be obtained without labor.

As described above, according to this embodiment, the wedge-shaped pressing member 5
The first flat surface (pressing surface) 55 can strongly and stably press the detent surface M of the shank S by wedge action, so that the cutting edge can be simplified as long as a boring bar having the same detent surface M is used. , Can be quickly and always held in a fixed position.

In this embodiment, the front end 1 of the insertion hole 12
In 3, the wedge-shaped pressing body 51 is inserted from the front end to the rear end 17, so that the boring bar 201 can be fixed at the position closest to the cutting edge, thereby improving the clamping strength. Therefore, when the protruding amount of the boring bar is small, the set screw 28 on the upper surface 26 can be eliminated. Further, when the boring bar is fixed in this manner, when the boring bar is broken, the screw member 61 with a reverse screw for pushing the wedge-shaped pressing body 51 is loosened without removing the holding body 11 from the tool post. Since the boring bar can be removed (extracted), replacement of the boring bar can be further simplified and speeded up.

Next, another embodiment of the present invention will be described in detail with reference to FIGS. However, in this embodiment, the notch 20 is provided for mounting the wedge-shaped pressing body 51, and the plate member 31 is attached as a separate member so as to close the upper surface in order to generate a wedge action. On the other hand, since only the following points are different and there is no essential difference, the same reference numerals are given to the same portions, and only the differences will be described. In the present embodiment, the screw mechanism is such that the wedge-shaped pressing member 151 is simply tightened directly with, for example, a hexagon socket head cap screw 161 without using the plate member 31 as in the above-described embodiment.

That is, in the boring bar holder 111 of this embodiment, the front end face 1 is provided at one side of the shank insertion hole 12.
A notch 120 formed by recessing one side of the shank insertion hole 12 is provided so that the plate member 31 of the above-described form is integrally provided when viewed from the three sides. However, as shown in FIG. 8, the notch (vacant space) 120 in this embodiment has a semi-circular upper part 133 on the inner peripheral surface as viewed from the front end 13 side, and a lower part cut by a width of the diameter. It is in the shape of a circle. The uppermost part (left and right center in FIG. 8) of the arc-shaped part of the notch part 120 has the same angle (10 degrees) with respect to the axis G1 of the shank insertion hole 12 from the front end 13 side to the rear end side. It is inclined.

On the other hand, the wedge-shaped pressing body 151 is formed so as to just fit into the notch 120 as shown in the figure.
In addition, a bolt insertion hole 153 is provided so that the hexagon socket head cap screw 161 is recessed, and the hexagon socket head cap screw 161 is inserted through the bolt insertion hole 153 so that the screw on the wall surface 23 at the back of the notch 120 is provided. It is configured to be screwed into the hole 24.
Note that the axis G2 of the bolt insertion hole 153 is
The seat surface 154 of the counterbore hole is a surface perpendicular to the axis G2 of the bolt insertion hole 153.

In this embodiment, however, the shank insertion hole 12
The shank S of the boring bar 201 is inserted into the hole, the detent surface M faces the lower surface (flat surface) 55 of the wedge-shaped pressing body 151, and the hexagon socket head cap screw 161 is screwed into the screw hole 24 of the wall surface 23 through the bolt insertion hole 153. . By doing so, the wedge-shaped pressing body 151 is pushed into the wall surface 23 side so as to be drawn in along the semi-arc-shaped inclined surface (generating line) above the notch 120, and the insertion hole 12 in the direction of the axis G1. Move closer to. As is clear from this, since the flat surface 55 of the wedge-shaped pressing body 151 is pressed against the detent surface M of the shank S of the boring bar 201, the same operation or effect as in the above embodiment is also obtained in this embodiment. There is.

However, in this embodiment, since the reverse screw is not required as the screw mechanism, and since the inclined surface of the cutout portion 120 is formed in an arc shape when viewed from the front end surface 13 side, the plate member 31 as another component as in the above embodiment is provided. Also, there is an effect that the mounting portion of the wedge-shaped pressing body 151 can be easily formed integrally with the holding body without requiring.

In each of the above embodiments, the boring bar holder is in the form of a rectangular tube itself. However, a cylindrical (cylindrical) boring bar fixed to the tool post by driving a pin or the like is used. The present invention can be similarly embodied in a holding body for use (also referred to as a sleeve). The present invention is not limited to the above-described embodiment, and can be embodied by appropriately changing the shape of the wedge-shaped pressing body and the screw mechanism without departing from the scope of the invention.

[0031]

As is clear from the above description, according to the boring bar holder of the present invention, when the boring bar holder is replaced, the boring bar holder is replaced as compared with the case of fixing with the set screw.
The height accuracy of the cutting edge can be obtained simply and quickly.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view of an embodiment of a boring bar holder according to the present invention.

FIG. 2 is an enlarged sectional view of a main part of FIG. 1;

FIG. 3 is a perspective view of a wedge-shaped pressing body used for the boring bar holding body of FIG. 1;

FIG. 4 is a partially broken left side view of FIG. 1;

FIG. 5 is a plan view of an inner diameter machining tool having a boring bar set on the boring bar holder of FIG. 1;

FIG. 6 is an enlarged sectional view of a main part of another embodiment of the boring bar holder according to the present invention.

FIG. 7 is a perspective view of a wedge-shaped pressing body used for the boring bar holder of FIG. 6;

FIG. 8 is a partially broken left side view of FIG. 6;

[Explanation of symbols]

 [Claims] 12 Shank insertion hole 11, 111 Boring bar holder 13 Front end of shank insertion hole 17 Rear end of shank insertion hole 24 Screw hole of boring bar holder 51, 151 Wedge-shaped pressing body 59 Wedge-shaped pressing body Screw hole 61 Screw member with screw to be screwed to reverse screw 161 Hexagon socket head bolt 201 Boring bar S Shank of boring bar M Shank detent surface G1 Shaft insertion hole shaft

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Shinya Takeuchi 14-18 Takatsuji-cho, Mizuho-ku, Nagoya F-term in Japan Special Ceramics Co., Ltd. (reference) 3C046 KK02

Claims (5)

[Claims] 1. A boring bar holder having a shank insertion hole into which a boring bar having a detent surface can be inserted on a side surface of a shank, wherein a wedge-shaped pressing body is mounted on one side of the shank insertion hole. A boring bar holder, wherein the wedge-shaped pressing body is pressed by a pressing means by a screw mechanism to press the detent surface of the shank by a wedge action. 2. The boring bar holder according to claim 1, wherein the pushing direction of the wedge-shaped pressing body is substantially the same as the axial direction of the shank insertion hole. 3. The boring bar holder according to claim 2, wherein the wedge-shaped pressing body is pushed from the front end side to the rear end side of the shank insertion hole. 4. The screw mechanism according to claim 1, wherein the boring bar holding member and the wedge-shaped pressing member are provided with screw holes forming reverse screws with the pressing direction of the wedge-shaped pressing member as an axis, and the screw holes are respectively provided in the two screw holes. 4. The boring bar holder according to claim 1, wherein a screw member provided with a mating screw is screwed into each screw hole. 5. A boring bar provided with a detent surface on a side surface of a shank in a shank insertion hole of the boring bar holder according to claim 1, wherein the detent surface is attached to the wedge-shaped pressing body. An inner diameter machining tool, which is inserted in opposition and is pressed by a wedge action on the detent surface of the shank by pushing the wedge-shaped pressing body by a pushing means by a screw mechanism.