JPH02185343A - Rotative cutter - Google Patents

Abstract

PURPOSE:To collect chips without scattering them so as to drastically improve working environment by attracting and discharging chips with centrifugal force accompanying the rotation of a fan by way of providing a cutter main body with a blade in case of a rotative cutter for a face milling machine. CONSTITUTION:At the time when a flat face cutting is practiced with a face milling machine, the air on the inner peripheral side of a pump chamber 38 is led along a blade 41b to the outer peripheral side of the pump chamber 38, furthermore guided along the inner peripheral face of a cylindrical body 35 and discharged through an exhaust air port 40, by the centrifugal force generated along with the rotation of a cutter main body 13. Consequently, negative pressure is generated on the inner peripheral wall of the pump chamber 38, and the air around an open port part 35e on the top edge of the cylindrical body 35 is attracted to the inner peripheral side of the pump chamber 38 through an inlet route 39. Accordingly, the chips formed by a cutter chip 16 are attracted into the inside of the pump chamber 38 together with the sucked air through the open port part 35e on the top edge of the cylindrical body 35 and discharged through an exhaust air port 40.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a milling tool, such as a face milling cutter, which is mainly used for surface cutting, and more specifically to a milling tool that can sequentially process chips generated during cutting. Regarding cutting tools.

[Prior art] As an example of a milling tool used for planar machining of a workpiece,
Conventionally, face milling cutters shown in FIGS. 7 to 9 have been known.

As shown in these figures, this face milling cutter has an approximately cylindrical cutter body 1 with a cutter body l attached to the outer periphery of the tip.
A plurality of grooves 2 are formed at equal intervals in the circumferential direction and open toward the tip and outer peripheral surfaces of the grooves 2. A throw-away tip (hereinafter abbreviated as a tip) 3 is inserted into the grooves 2 by a clamp screw 4. A chip pocket 6 having an arcuate wall surface is formed on the outer circumferential surface of the cutter body 1 facing the rake surface 3a of each chip 3, and is detachably attached by a wedge member 5 to be tightened. A center hole 7 is formed at the center of the cutter body 1, passing through the cutter body 1 in the axial direction.

The face milling cutter constructed in this way has the center hole 7 fitted into the fitting shaft 11 of the arm μlO, which is attached to the main shaft 8 of the machine body via the key 9, and then tightened by the pin 1-12. It is fastened and integrated with the main shaft 8. In this state, the cutter body 1 is rotated around its axis by the main shaft 8 and sent in a direction perpendicular to the axis, so that the tip 3 planes the workpiece. The chips generated at this time are guided from the cutting surface 3a to the wall surface of the chip pocket 6, rounded up, and then discharged outward in the circumferential direction of the cutter body 1.

[Problems to be Solved by the Invention] By the way, since the conventional face milling cutter described above simply guides and discharges the generated chips outward in the circumferential direction, the chips are transferred to the machine as the cutter body 1 rotates. The chips are scattered widely around the surrounding area, which not only worsens the working environment but also sometimes makes the work dangerous, and also requires a considerable amount of time to dispose of the chips after cutting.

In addition, as cutting continues, chips gradually accumulate on the workpiece and the machine table (as a result, the heat of these chips causes thermal deformation of the workpiece and machine, deteriorating machining accuracy. Alternatively, there was also the drawback that chips were caught in the chip 3, impairing the quality of the cut surface.

Furthermore, there is a risk that chips scattered around the machine may enter the sliding surfaces of the machine, leading to deterioration of accuracy and shortened lifespan of the machine itself.

The present invention was made against this background, and an object of the present invention is to provide a milling tool that can process chips generated during cutting without scattering them around.

[Means for Solving the Problems] In order to solve the above problems, the milling tool of the present invention has a cutting tool that covers the cutter body outwardly from the circumferential surface of the cutter body and whose tip is directed toward the tip of the cutter body. A cylindrical body to be opened is disposed so as to be rotatable relative to the cutter body, and between the inner peripheral surface of the cylindrical body and the proximal peripheral surface of the cutter body, A pump chamber is formed that bulges out in the direction, and a plurality of blades protruding outward in the radial direction of the cutter body are arranged on the circumferential surface of the cutter body within the pump chamber along the circumferential direction of the cutter body. A suction passage is formed that communicates from the opening at the tip of the body to the inner circumferential side of the pump chamber, and an outlet that passes through the cylinder and communicates with the inside and outside of the pump chamber is formed on the outer circumferential side of the pump chamber. It is something.

In addition, in order to more reliably dispose of chips, a chip is placed at the tip of the cutter body, facing the rake surface of the cutting blade tip at a distance, and guiding the chips generated by the cutting blade tip to the suction path. Preferably, a guide member is provided.

In order to further improve the suction efficiency, it is preferable that the gap between the outer circumferential end surface of the blade and the inner circumferential surface of the cylindrical body be gradually enlarged as it approaches the discharge port along the circumferential direction of the cutter body.

Further, as the blade, it is suitable to have a spiral blade shape that gradually curves toward the rear in the cutter rotational direction as it goes radially outward of the cutter body.

[Operation] According to the milling tool having the above configuration, the centrifugal force generated as the cutter body rotates causes the air on the periphery of the pump chamber to be guided to the outer periphery of the pump chamber along the blades, and further to the outer periphery of the cylindrical body. It is guided along the inner peripheral surface and discharged from the exhaust port. Therefore, negative pressure is generated on the inner circumferential side of the pump chamber, and air around the opening at the tip of the cylinder is sucked into the inner circumferential side of the pump chamber through the suction path.

Therefore, the chips generated by the cutting tip are sucked together with the intake air into the pump chamber from the opening at the tip of the cylinder, and are discharged from the exhaust port.

In addition, in the case where a chip guide member is provided at a position facing the rake face of the cutting chip, chips generated by the cutting chip pass through the gap between the chip guide member and the chip rake face to the cylindrical body. Since the chips are successively guided to the tip opening side, the chips can be collected more reliably.

Furthermore, in the case where the gap between the outer circumferential end surface of the blade and the inner circumferential surface of the cylindrical body increases as it approaches the exhaust port,
Even if the amount of air guided toward the exhaust port on the outer circumference of the pump chamber increases as it approaches the exhaust port of the pump chamber, no back pressure is generated on the downstream side of the pump chamber. The suction efficiency is not impaired.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

In FIGS. 1 to 3, reference numeral 13 indicates a cutter body. This gutter body 13 is a substantially cylindrical body in which a center hole 14 is formed in the center thereof, passing through the cutter body 13 in the axial direction. On the outer periphery of the enlarged diameter portion of the cutter body 13,
A plurality of grooves 15 are formed at equal intervals in the circumferential direction. Chips 16 having a flat plate shape are removably attached to these grooves 15 by wedge members 18 that are tightened with clamp screws 17, and cutting edges 19 are formed on the ridges of each chip 16.
One of the blades protrudes slightly from the distal end surface of the cutter body 13. Further, a chip pocket 20 having a substantially arcuate wall surface is formed at a position facing the chip scooping surface 16a at the tip of the cutter body 13.

The base end side of the cutter body 13 is fitted with an adapter 21. The adapter 21 is detachably attached to the main shaft 23 of the machine body via a spacer 24 with a plurality of bolts 22. Further, between the base end surface of the adapter 21 and the distal end surface of the spacer 24, a center plug 25 for centering the adapter 21 with respect to the main shaft 23;
A key 26 for transmitting the rotation of the main shaft 23 to the adapter 21 is also interposed.

A tightening washer 27 is removably attached to the distal end side of the adapter 21 with a connecting bolt 28. For this tightening, there are projections 2 on the circumferential surface of the washer 27 that extend outward in the radial direction.
9 are formed at equal intervals in the circumferential direction. Also,
These protrusions 2 are also formed on the inner peripheral surface of the center hole 14 of the cutter body 13.
9 and the same number of small diameter protrusions 30 are formed, and when these small diameter protrusions 30 and the protrusions 29 are engaged, the cutter main body 13 is restricted from moving in the axial direction, and the adapter 2
It is designed to be connected to 1.

Further, a key 31 is provided on the tip surface of the adapter 21, and a key 31 is provided on the tip surface of the adapter 21.
It is attached by 2. When the adapter 21 is connected to the cutter body 13, the key 31 is fitted into a notch 33 continuous to the small diameter protrusion 30 of the cutter body 13 so as to be freely movable in the circumferential direction. In the state in which the notch part 30 is engaged with the cutter body 13, the notch part 33 engages with the front wall surface in the cutter rotation direction (Y1 direction in FIG. 2), thereby transmitting the rotation of the adapter 21 to the cutter body 13. . Further, the key 31 is also engaged with a key groove 34 formed on the back surface of the washer 27, so that the rotation of the adapter 21 and the tightening force are also transmitted to the washer 27.

As shown in FIGS. 1 and 2, a cylindrical body 35 that covers the cutter body 13 is disposed outside the circumferential surface of the cutter body 13. As shown in FIGS. The base end 35a of the cylindrical body 35 is hermetically connected with a bolt 37 to the front surface of a spindle head 36 that rotatably supports the spindle 23. Further, the tip 35b of the cylindrical body 35 is extended to a position that covers the upper part of the chip pocket 20 formed on the circumferential surface of the tip of the cutter body 13, and the inner circumferential surface and the circumferential surface of the tip of the cutter body 13 are connected to each other. A slight gap is provided between them. If this gap is too small, there is a risk that the cutting blade 19 will dig in due to the eccentricity of the cylinder 35, so it is desirable to secure at least 0.5 mm or more, and conversely, if it is too large, the chip suction efficiency will be reduced. Since a decline in
Preferably, it is necessary to regulate it within 1llllll1.

Additionally, the cylindrical body tip 35b is connected to the cylindrical intermediate part 35c and the screw 3.
5d.

The intermediate portion 35c of the cylinder 35 has a diameter larger than that of the cylinder tip 35b, and there is a cutter body between the inner peripheral surface of the intermediate portion 35c and the peripheral surface of the adapter 21 that is continuous with the proximal peripheral surface of the cutter body 13. 13
A pump chamber 38 is formed that bulges outward in the radial direction. The inner circumferential side of this pump chamber 38 is connected to a suction passage 3 formed between the cylindrical body tip 35b and the circumferential surface of the tip of the cutter body 13.
It communicates with the tip opening 35e of the cylindrical body 35 via 9. Further, a tubular exhaust port 40 is fitted into the circumferential surface of the intermediate portion 35C of the cylinder, thereby communicating the pump chamber 38 with the outside.

Furthermore, as shown in FIG. 4, the inner circumferential surface of the cylindrical intermediate portion 35C gradually moves outward in the cutter radial direction as it approaches the exhaust port 40 along the rotational direction of the cutter body 13 (Y1 direction in the figure). As a result, the cross-sectional area of the pump chamber 38 extends from the exhaust port 40 along the direction of rotation of the cover.
It is designed to gradually increase as it approaches .

As shown in FIGS. 1 and 4, a ring 41 is detachably attached to the circumferential surface of the adapter 21 in the pump chamber 38 with bolts 41a. Eight blades 41b are formed on the peripheral edge of the ring 41 at equal intervals in the circumferential direction of the cutter. These blades 41b are formed in the shape of a spiral blade that gradually curves rearward in the cutter rotation direction (Y1 direction in FIG. 4) as it goes outward in the cutter radial direction. In addition, the outer peripheral side end surface of each blade 41b and the cylindrical intermediate portion 35
The gap between c and the inner circumferential surface is such that there is a slight gap at the part where the pump chamber 38 is narrowest (a position slightly closer to the front side in the direction of cutter rotation than the exhaust port 40).

In addition, as shown in FIGS. 1 to 3, the cutter body 1
A chip guiding member 42 having a flat plate shape is integrally attached with a bolt 43 at a position facing each chip rake face 16a at the tip of the chip.

The surface of these chip guide members 42 is connected to the cutter body 13.
The end surface 4 is positioned in the cutter axis direction so that the tip surface and the road surface are aligned with each other, and the end surface 4 faces the chip rake surface 16a.
The cutter is positioned in the circumferential direction so that there is a gap t between the tip 2a and the tip rake face 16a, which allows the passage of chips generated by the cutting edge 19 of the tip 16.

Further, a groove 44 that opens toward the end surface 42a and the chip pocket 20 is formed on the back surface of the chip guide member 42, and is configured to prevent chips guided along the gap t between the end surface 42 and the chip scooper 16a from being clogged. Consideration has been made to allow the chips to be discharged to the chip pocket 20 side without causing any damage.

To perform plane cutting using the face milling cutter configured as described above, first connect the adapter 21 to the main shaft 23 with the bolt 22, and also attach the intermediate part 35c of the cylinder 35 to the main shaft head 36 with the bolt 37. Fixed by Note that, at this time, the cylindrical body tip portion 35b is removed from the cylindrical body intermediate portion 35c.

After this, as shown by the two-dot chain line in Fig. 2, the cutter body 1
To tighten the cutout portion 33 of No. 3, the cutter body 13 is pushed into the adapter 21 side after facing the protrusion 29 of the washer 27, and its proximal end is fitted into the adapter 21. and,
The cutter body 13 is tightened with its small diameter protrusion 30 until the protrusion 29 of the washer 27 engages in the cutter rotation direction (second
(Y1 direction) in the opposite direction, then connect bolt 2
Tighten 8. As a result, the cutter body 13 is sandwiched between the adapter 21 and the washer 27 to prevent its axial movement, and its rotation is restrained by the key 31 fitted in the notch 33. main shaft 23
is connected with.

After the work of attaching the cutter body 13 to the main shaft 23 is completed as described above, the distal end portion 35b of the cylinder body 35 is connected to the cylinder body intermediate portion 35c by the screw 35d to cover the circumferential surface of the cutter body 13. Then, by rotating the cutter body 13 around its axis in the Y1 direction in FIG. 2 and sending it out in a direction perpendicular to the axis, the cutting edge 19 of the tip 16 cuts the work material.

At this time, chips generated along the rake surface 16a of the chip 16 are guided to the gap t between the end surface 42a of the chip guide member 42 and the chip rake surface 16a, and are discharged into the chip pocket 20.

On the other hand, as the cutter body 13 rotates, the air on the inner circumferential side of the pump chamber 38 is pressed against the blades 41b and pushed forward in the cutter rotational direction, but at the same time, the air flows outward in the radial direction of the cutter body 13. (Because centrifugal force acts, as a result, the air on the inner circumferential side of the pump chamber 38 is sequentially moved toward the blade 41.
b to the outer circumferential side of the pump chamber 38.

The air sent out to the outer circumferential side of the pump chamber 38 is
The gas is guided to the exhaust port 40 along the inner circumferential surface of the cylinder intermediate portion 35c, and is discharged from the exhaust port 40.

As a result, negative pressure is generated on the inner circumferential side of the pump chamber 38, and the cylindrical body 3 communicates with the inner circumferential side of the pump chamber 38 via the suction passage 39.
Air around the tip 16 is successively sucked through the tip opening 35e of the tip 5.

When negative pressure is generated on the inner circumferential side of the pump chamber 38, the chips guided by the chip guide member 42 and discharged into the chip pocket 20 are sucked into the inner circumferential side of the pump chamber 38 together with air. Then, the sucked chips are sequentially pumped into the pump chamber 38 along with the air.
The gas is guided to the outer peripheral side and discharged from the exhaust port 40.

In this case, the amount of air guided toward the outer peripheral side of the pump chamber 38 toward the exhaust port 40 is
Since air is sucked from the entire circumference of 5e, it gradually increases as it approaches the exhaust port 40, but since the cross-sectional area of the pump chamber 38 increases as it approaches the exhaust port 40,
The increase in the amount of air does not generate back pressure in the vicinity of the exhaust port 40 in the pump chamber 38, which does not affect the suction efficiency of air from the inner peripheral side of the pump chamber 38.

If it becomes necessary to replace the tip 16 during cutting, loosen the connecting bolt 28, then rotate only the cutter body 13 in the direction Y1 in FIG. 13 is disengaged from the small diameter protrusion 30, and then the cutter body 13 is taken out from inside the cylindrical body tip 35b.

Then, the tip 16 is removed from the cutter body 13 and replaced with a new tip, and then the cutter body 13 can be tightened again to engage the washer 27 and connect it to the adapter 21.

As explained above, according to the face milling cutter of this embodiment, chips generated during cutting are successively guided to the chip pocket 20 by the chip guide member 42, and further
Since the suction force generated by the rotation of b draws it into the pump chamber 38 and discharges it from the exhaust port 40, the generated chips can be collected from the exhaust port 40 without being scattered around the machine. Therefore, the working environment is significantly improved and the time required for chip disposal is also significantly reduced. In addition, since chips do not accumulate on the workpiece or the table of the machine body, there is no deterioration of machining accuracy due to thermal deformation of the workpiece or machine, or deterioration of the quality of the cut surface due to chipping. Furthermore, the intrusion of chips into the sliding surfaces of the machine body is prevented, and deterioration of the precision and life of the machine body is also prevented.

Further, in this embodiment, the cutter body 13 can be attached and detached by simply operating the connecting bolt 28 while the washer 27 and the cutter body 13 are engaged with each other.
There is no need for the operator to hold the cutter body 13 when operating the cutter body 13. Therefore, the cutter body 13 is
Although it is difficult to grasp because it is covered with dirt, the workability of replacing the cutter is not affected in any way.

In addition, in this embodiment, the cylinder body 35 is fixed to the spindle head 36, thereby restraining the cylinder body 35 against the rotation of the cutter body 13 and making it possible to collect chips from the exhaust port 40. The milling tool of the present invention is not limited to this. For example, chips can be collected even if the cylindrical body 35 is rotatably supported by the adapter 21 and its rotation is restrained by fitting a hose or the like to the exhaust port 40. In short, the cylindrical body 35 It suffices if it is rotatably provided relative to the main body.

In addition, in this embodiment, negative pressure is generated on the inner peripheral side of the pump chamber 38 due to the centrifugal force generated by the rotation of the blade 41b, and suction force is generated.
This largely depends on the turning diameter of b, that is, the circumferential speed of the outer peripheral side of the blade 41b. Therefore, when designing the blade 41b, it is desirable to have a large turning radius within an allowable range.

Further, in this embodiment, the case of a throw-away type face milling cutter in which the tip 16 is detachably attached to the cutter body 13 has been described, but the milling tool of the present invention is not limited to this, and the tip is attached by brazing. Of course, the present invention can also be applied to a face milling cutter or the like.

Furthermore, in this embodiment, a chip guide member 42 is especially provided at the tip of the cutter body 13, but this is only useful when the blades 41b can provide sufficient suction to completely collect chips, or when cutting cast iron. It may be omitted if dust-like chips are generated, such as in the case of

Furthermore, in this embodiment, the vane 41b is formed in the shape of a spiral blade, and the inside of the pump chamber 38 is configured in the shape of a spiral pump.
The milling tool of the present invention is not limited to this. That is, the blades 41b may be of any type as long as they generate suction force by utilizing the centrifugal force generated as the cutter body 13 rotates, and various modifications are possible.

For example, as shown in FIG. 5, flat blades 51 are slidably fitted into a plurality of grooves 50 formed on the circumferential surface of the adapter 21 at equal intervals in the circumferential direction. body 35
The inside of the pump chamber 38 may be configured in the shape of a vane pump by forming the inner circumferential surface of the pump chamber 38 in a perfect circular shape and further arranging the cylinder body 35 eccentrically with respect to the adapter 21 . In this case, each blade 51 is pushed outward in the cutter radial direction by the centrifugal force generated as the cutter body 13 rotates. Therefore, the end face of each vane 51 is always in close contact with the inner peripheral surface of the cylindrical body 35, and the air sucked into the inner peripheral side of the pump chamber 38 is more reliably guided to the exhaust port 40.

In addition to this, as shown in FIG. It is also possible to form the surface into a perfect circle so that the inside of the pump chamber 38 is configured in the shape of a regenerative pump.

In this case, in order to prevent the air guided along the inner peripheral surface of the cylinder 35 from flowing out beyond the exhaust port 40 to the upstream side of the pump base ring 38, the exhaust port on the inner peripheral surface of the cylinder 35 is closed. 40, it is necessary to provide a backflow prevention plate 53 that narrows the gap between the end surface of the blade 52 and the inner peripheral surface of the cylinder body 35.

[Effects of the Invention] As explained above, according to the present invention, air is sequentially sucked into the pump chamber from the tip opening of the cylindrical body through the suction path by the centrifugal force generated as the blades rotate. Chips generated during cutting are successively sucked into the pump chamber and discharged from the exhaust port.

Therefore, according to this embodiment, the chips can be sequentially collected from the exhaust port without being scattered around the machine, thereby significantly improving the working environment and significantly shortening the chip processing time. Furthermore, thermal deformation and chip clogging due to the accumulation of chips are eliminated, and the intrusion of chips into machine sliding surfaces is also eradicated, preventing deterioration of machining accuracy, deterioration of cut surface quality, and shortening of machine life. .

In addition, in the case of a cutter in which a chip guide member is provided at the tip of the cutter body, chips generated along the rake face of the cutting blade tip are transferred to the chip guide member (through the gap between the cutting face and the cylinder). Since the chips are guided toward the opening at the tip of the body, the chips can be collected more reliably.

Furthermore, in the case where the gap between the outer circumferential end surface of the vane and the inner circumferential surface of the cylinder is gradually enlarged as it approaches the exhaust port, even if the amount of air sucked into the pump chamber increases as it approaches the exhaust port, Since there is no back pressure on the downstream side of the pump chamber, the suction efficiency is significantly increased.

[Brief explanation of the drawing]

1 to 4 show an embodiment of the present invention,
Figure 1 is an axial sectional view, Figure 2 is a bottom view, Figure 3 is an enlarged view of the outer circumference of the tip of the cutter body, and Figure 4 is inside Figure 1-A.
5 and 6 are respectively axially perpendicular sectional views of the inside of the pump chamber in a modification of the above embodiment, and FIGS. 7 to 9 show a conventional face milling cutter.
FIG. 7 is an axial sectional view, FIG. 8 is a bottom view, and FIG. 9 is an enlarged view of the outer periphery of the tip of the cutter body. 13... Cutter body, 14... Center hole, 16... Throwaway tip, 16a...
...Chip rake face, 35...Cylinder body, 35
b...Cylinder tip, 35e...Cylinder tip opening, 38...Pump chamber, 39...
...Intake path, 40...Exhaust port, 41b, 51.
52...Blade, 42...Chip guide member.

Claims (4)

[Claims] (1) In a milling tool in which a cutting tip is attached to the outer periphery of a tip of a cutter body that is rotated around an axis, a cutting tip is provided on the outside of the circumferential surface of the cutter body, and the tip thereof covers the cutter body and whose tip is attached to the outer periphery of the cutter body. A cylindrical body that opens toward the distal end of the cutter body is arranged so as to be rotatable relative to the cutter body, and between the inner circumferential surface of the cylindrical body and the proximal circumferential surface of the cutter body. , a pump chamber that bulges outward in the radial direction of the cutter body is formed, and a blade that protrudes outward in the radial direction of the cutter body is provided on the circumferential surface of the cutter body in the pump chamber. A plurality of suction passages are arranged along the direction to form a suction passage communicating from the tip opening of the cylindrical body to the inner circumferential side of the pump chamber, and the suction passages are provided on the outer circumferential side of the pump chamber through the cylindrical body. A milling tool characterized by having a discharge port that communicates with the inside and outside of the tool. (2) A chip guide member is provided at the tip of the cutter body, facing the rake surface of the cutting blade tip at a distance, and guiding chips generated by the cutting blade tip to the suction path. The milling tool according to claim 1. (3) The gap between the outer circumferential end surface of the blade and the inner circumferential surface of the cylindrical body is gradually enlarged as it approaches the discharge port along the direction of rotation of the cutter. The milling tool described in 2. (4) The blade according to claim 1, claim 2, or claim 3, wherein the blade is formed in a spiral blade shape that gradually curves toward the rear in the cutter rotational direction as it goes radially outward of the cutter body. Milling tools.