JP3215025B2 - Rotary bite - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary tool in which a disc-shaped throw-away tip (hereinafter referred to as a tip) is rotatably mounted on the tip of a tool body.

[0002]

2. Description of the Related Art As a rotary tool of this type, the inventors of the present invention have proposed a rotary tool as shown in FIGS. 7 to 10 in Japanese Patent Application Laid-Open No. 7-112305. This rotary tool is used for outer diameter cutting of a work material W as shown in FIG. 7, and is a rectangular shape held on a tool rest of a machine tool so as to extend along a horizontal plane serving as a reference plane P. At the tip of the shaft-shaped cutting tool body 1,
The disk-shaped chip 2 is configured to be rotatable around its central axis O, and the intersection between one of the circular surfaces 3 arranged upward of the chip 2 and the peripheral surface 4 of the chip 2 is provided. A cutting edge 5 is formed at the ridge line. In this chip 2, cutting edges 5 and 5 are formed at the intersection ridges of the two circular surfaces 3 and 3 and the peripheral surface 4, so that two cutting edges 5 can be used with one chip 2. It is possible.

As shown in FIG. 10, a center axis 6, 6 is formed at the center of the two circular surfaces 3, 3 on the chip 2, while a cutting tool body 1 for holding the chip 2 therebetween.
Shaft holes 9, 9 into which the above-mentioned central shafts 6, 6 are inserted are formed in the clamp piece 7 and the sheet 8 at the distal end, so that the chip 2 is rotatable around its axis O.
Further, the clamp piece 7 presses the chip 2 toward the sheet 8 by a brake washer 11, a wave washer 12, a coil spring 13 and the like loosely inserted around a clamp screw 10 of an attachment portion to the tip of the cutting tool body 1. The pressing force to be applied can be adjusted so as to be a predetermined pressing force, whereby the driven rotation speed of the chip 2 can also be adjusted appropriately.

[0004] Further, the tip 2 has a negative front rake angle α as shown in FIG. 8 and a negative front rake angle α as shown in FIG. The reference plane P is set so that the lateral rake angle β is given.
The cutting edge 5 cuts the outer diameter of the work material W, and the cutting force at that time also causes the tip 2 itself to be driven and rotated about the central axis O, thereby The cutting resistance is reduced, and the frictional resistance between the tip 2 and the work material W is also reduced, so that the wear and the like of the tip 2 are suppressed. As shown in the figure, when performing the outer diameter cutting of the work material W, when the front rake angle α is set to −6 °, the lateral rake angle β
Is set to about -36 °, the effect of reducing the cutting resistance and wear is high, and when the end face of the work material W is cut, when the horizontal rake angle β is set to −6 °, Rake angle β
It is known from the results of cutting tests and the like that it is desirable to set the angle to about -36 °.

[0005]

However, in such a conventional rotary tool, as described above, the chip 2 has the center shafts 6 and 6 formed on the two circular surfaces 3 and 3 thereof, and the clamp piece 7 and the sheet 8. In order to perform high-precision cutting, the rotational trajectory of the cutting edge 5 is made to be an accurate circle with respect to the center axis O of the tip 2 by being inserted into the shaft holes 9, 9 of the cutting tool 5. The degree of concentricity between the cutting edge 5 and the two center axes 6 and 6 and the center axis 6 and 6
And the concentricity between the shaft holes 9 and 9 into which they are inserted, and the concentricity between the central shafts 6 and 6 and between the shaft holes 9 and 9 must also be adjusted with high accuracy. However, when the number of elements requiring accuracy is increased in this way, it is difficult to obtain the high machining accuracy as described above due to accumulation of errors included in each element, and conversely, when trying to obtain such high accuracy, Each component must be machined with very high precision, and its assembly also requires considerable skill.

Further, in the above rotary tool, the tip 2 is mounted by inserting one center shaft 6 into the shaft hole 9 of the clamp piece 7. Since it is frequently attached and detached when replacing 5 or when replacing the chip 2 itself,
There is a problem that an error is likely to occur in the attachment to the cutting tool body 1. Accordingly, an error easily occurs in the concentricity between the shaft hole 9 of the clamp piece 7 and the central axis 6 of the chip 2 and the concentricity with the shaft hole 9 of the sheet 8, and the processing of the rotary tool is performed. Accuracy may be further impaired.

The present invention has been made under such a background, and the rotation locus of the cutting edge around the center axis of the insert can be easily made into an accurate circular shape, and high machining accuracy can be obtained. The purpose is to provide a simple rotary tool.

[0008]

In order to solve the above-mentioned problems and to achieve such an object, a rotary bite according to the present invention comprises at least one of a circular surface and a peripheral surface at the tip of a shaft-shaped bite body. In a rotary tool having a disk-shaped chip having a cutting edge formed at an intersection ridge portion thereof detachably mounted, a tip mounting seat for defining a disk-shaped recess is provided at the tip of the tool body. The rotatable sheet is provided so as to be rotatable around the central axis of a disk formed by the recess, and the chip is
In the recess formed by the chip mounting seat of the sheet, the central axis of the circular surface to coincide with the center axis of the disc formed by the recess fitted, whereupon the pivotable about the central axis of the circular form surface
Both can be connected to the above-mentioned cutting tool body and pressure detection means
While forming a fluid flow path, the sheet has the chip
Opening of the flow path by rotation of the sheet accompanying rotation of the
An opening / closing means for alternately closing is provided .

However, in the rotary cutting tool having such a configuration, if the roundness of the cutting edge of the chip and the concentricity between the center axis of the circular surface of the chip and the center axis of the sheet are accurate, the cutting edge of the cutting edge is determined. Since it is possible to secure high machining accuracy by making the rotation locus an accurate circle, as in the above-mentioned conventional rotary tool, the roundness of the cutting edge and the concentricity with respect to the center axis, and the difference between the center axis and the shaft hole Compared to the case where concentricity or concentricity between center axes or between shaft holes is required, the number of elements that affect machining accuracy can be reduced, and the effect of errors of each element is also suppressed. It is possible to easily obtain a desired processing accuracy. Also, the chip
Since only the circular surface side that is not subjected to cutting is fitted by fitting into the concave portion of the chip mounting seat, a center shaft is provided on both circular surfaces and one of them is inserted into the shaft hole of the clamp piece as in the related art. There is no need to do so, so that the clamp piece only needs to abut and hold the chip. Therefore, it is possible to prevent the mounting accuracy of the clamp piece from affecting the processing accuracy, and it is possible to more reliably and easily obtain high processing accuracy.

Here, the tip mounting seat is formed in a cylindrical shape with a bottom, and the disc-shaped concave portion is defined by an inner peripheral surface and a bottom surface of a cylindrical wall portion of the bottomed cylinder which makes an annular circumference. By doing so, it is possible to secure a large contact area between the chip and the mounting seat, and to increase the chip mounting rigidity compared to the conventional case where the chip is held by the center shaft inserted into the shaft hole, Processing accuracy can be improved. Also,
In a state where the chip is mounted, if a gap is defined between the peripheral surface of the chip and the concave surface of the cutting tool body facing the peripheral surface, the flank is formed as a flank during cutting. Even if the welded material adheres to the peripheral surface, it is possible to prevent the rotation of the chip from being interfered, and it is possible to prevent fine chips and the like from escaping from this gap and causing bite or the like. .

On the other hand, in a rotary tool using such a disk-shaped tip, since the tip is disk-shaped, the shape visually observed is the same regardless of whether it is rotating or stationary at the time of cutting. Therefore, even if the chips come to a standstill due to the above-described biting of the chips, the operator may not be able to recognize the chips. If the cutting is continued while the chip is stationary, the cutting resistance, which has been reduced by the rotation of the chip, increases, and the cutting edge is locally worn away only in the portion provided for cutting. As a result, the life of the insert is significantly impaired, and when the insert is re-engaged and the tip is rotated again, the abraded portion may leave uncut or scratches on the machined surface of the work material, resulting in the machining accuracy described above. There is a risk that the improvement of the quality will be impaired.

However, in the rotary tool according to the present invention, on the other hand, a fluid flow path connectable to the pressure detecting means is formed in the tool body, while the sheet is provided in the sheet with the rotation of the chip. Opening / closing means for alternately opening and closing the flow path by rotating the sheet is provided. Therefore, while the sheet is rotating together with the chip during cutting, the flow path of the cutting tool body is alternately opened and closed by the opening and closing means, and the pressure of the fluid flowing through the flow path fluctuates accordingly. When the rotation of the chip is confirmed while the chip and the sheet are stopped by biting, the flow path remains open or closed, and the detected pressure is constant without fluctuation of pressure. It can be seen that the chip is stationary.

For example, in the case of adopting such a configuration, the flow path of the fluid is formed so as to open toward the rotating portion of the sheet, while the flow path is formed in the sheet at a predetermined rotation position. When the sheet is at the predetermined rotation position, the passage of the cutting tool body communicates with the outside through the passage of the sheet when the passage is formed as the opening / closing means so as to open the passage to the outside of the cutting tool body. When the pressure of the fluid in the flow path decreases and the rotation position of the sheet deviates from the predetermined rotation position, the flow path is closed and the pressure of the fluid increases, so that the rotation of the sheet with the rotation of the chip When the position changes, the pressure of the fluid repeatedly fluctuates and rises and falls, and rotation of the tip is confirmed. Conversely, if the tip is stationary and the rotational position of the sheet is constant, the pressure will remain unchanged, with the pressure increasing or decreasing.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS.
One embodiment of the rotary cutting tool according to the present invention will be described. In the present embodiment, the cutting tool main body 21 has a mounting portion 23 formed at the tip of a column-shaped shank 22 having a square cross section, and has a substantially T-shape in a side view.
A disk-shaped chip 24 is detachably attached so as to be rotatable around its central axis O. And
The cutting tool body 21 is supported by a tool rest of a machine tool such that the base end side of the shank 22 is extended along a horizontal reference plane P, and is subjected to cutting.

The tip 24 is formed from a hard material such as a cemented carbide. In the present embodiment, a pair of circular surfaces 25, 25, which are coaxial with respect to the central axis O and have the same shape and size, and these circular surfaces 25, , 25 having a peripheral surface 26 connecting the circumferences thereof, and having a disk shape or a columnar shape. The central axis O is provided at the intersection ridge line between the pair of circular surfaces 25, 25 and the peripheral surface 26. Circumferential cutting blades 27, 27 are formed at the center. That is, the tip 24 has a shape symmetrical with respect to the front and back sides in the direction of the central axis line O, whereby the use of the cutting blade 27 twice with one tip 24 is enabled.

Accordingly, when the tip 24 is mounted on the mounting portion 23 of the cutting tool body 21, one of the circular surfaces 25 connected to the cutting blade 27 used for cutting is a rake face and the peripheral face 26 is a flank. And the other circular surface 25
Will be a seating surface for a chip mounting seat described later. In a state where the tip 24 is mounted on the cutting tool main body 21, a predetermined front rake angle and a predetermined side rake angle are given to a portion provided for cutting the cutting edge 27, and the size of the front rake angle is outside the work material. For diameter cutting and end face cutting,
The respective rake angles α and β in the case of the outer diameter and end face cutting of the rotary tool described above are made equal.

On the other hand, as shown in FIG. 4, the mounting portion 23 at the tip of the cutting tool body 21 on which such a chip 24 is mounted is directed downward from the tip end surface of the mounting portion 23 with respect to the reference surface. A substantially cylindrical bearing member 29 is fitted into the mounting hole 28, and a seat 31 is inserted into the inner peripheral hole 30 of the bearing member 29 by a seat 31. 31A is fitted so as to be rotatable around its central axis C. Further, at the upper end of the sheet 31, a bottomed cylindrical chip mounting seat 32 is formed integrally with the sheet 31 coaxially with the axis C, and inside the bottomed cylinder formed by the chip mounting seat 32. Is
A concave portion 33 is defined as a disk-shaped space.

Here, the cylindrical wall portion 32A of the chip mounting seat 32 having the bottomed cylindrical shape has an inner peripheral surface perpendicular to the bottom surface 32B of the chip mounting seat 32 and makes a round around the central axis C. The concave portion 33 is defined by the inner peripheral surface of the cylindrical wall portion 32A and the bottom surface 32B, and has a size such that the chip 24 can be fitted therein. Then, the chip 24 moves its axis O to the sheet 31.
In this state, the circular surface 25 serving as the seating surface is formed on the bottom surface 32B, and the peripheral surface 2 on the circular surface 25 side.
The six portions are brought into close contact with the inner peripheral surface of the cylindrical wall portion 32A, respectively, fitted into the concave portions 33 and seated on the chip mounting seat 32. In this embodiment, the chips 24 are integrally formed with the seat 31 along the axis O, It is rotatable around C and is attached to the attachment portion 23 of the cutting tool body 21. When the chip 24 is mounted on the mounting portion 23 in this manner, a chip mounting seat 32 is provided between the peripheral surface 26 of the chip 24 and the concave surface 23A of the mounting portion 23 opposed thereto.
The gap S slightly larger than the thickness of the cylindrical wall portion 32A
Is formed.

Further, a flange portion 34 is formed at the upper end of the bearing member 29 to closely contact the periphery of the opening of the mounting hole 28 and to slidably support the chip mounting seat 32 of the seat 31. I have. In addition, the tool body 21
The retaining screw 3
A screw hole 36 into which the screw 5 is screwed is provided. The tip of the retaining screw 35 is attached to the inner peripheral hole 30 of the bearing member 29.
And engages with an annular groove 37 formed at the lower end side of the shaft portion 31A of the seat 31 to thereby prevent the bearing member 29 and the seat 31 from coming off.

Further, a clamp screw hole 38 and a pin hole 3 are formed in the upper portion of the mounting portion 23 in parallel with the mounting hole 28.
9 is formed, a clamp screw 41 inserted into the clamp piece 40 is screwed into the clamp screw hole 38, and the clamp piece 40 is fitted into the pin hole 39 by being fitted into the clamp piece 40. Pin 42 that restrains the rotation of
Is inserted. The tip of the clamp piece 40 extends on an extension line above the axis C of the sheet 31, and the lower surface 40A of the clamp piece 40 with the chip 24 mounted thereon is
The chip 24, which is in contact with the center of the circular surface 25 which is a rake face of the chip 24 and is sandwiched between the chip mounting seat 32 of the sheet 31, is pressed down and held to such an extent that its rotation is not hindered. It has been done.

The tip of the clamp piece 40 is formed in a wedge shape as shown in the drawing, so that chips generated during cutting can flow smoothly in a predetermined direction and curl to an appropriate diameter. It is planned. Further, the opening side of the clamp screw hole 38 is formed so as to increase the diameter by one step, and a coil spring 43 loosely inserted into the clamp screw 41 is accommodated in the enlarged diameter portion. The piece 40 is always urged upward and is in contact with the head 41A of the clamp screw 41.

Further, in the present embodiment, a flow path 44 of compressed air (fluid) is perforated from the rear end side of the shank 22 of the cutting tool body 21 to the front end surface of the mounting portion 23. At a position perpendicular to the central axis C of the seat 31, the inner peripheral hole 30 extends through the bearing member 29 in a direction perpendicular to the central axis C of the seat 31.
It is formed so that it may open. The flow path 44
A supply source of compressed air from a machine tool (not shown) is connected to a rear end of the rear end, and compressed air can be supplied to the flow path 44 at a predetermined pressure during cutting. Furthermore,
A branch flow path 45 is provided between the supply source and the opening to the inner peripheral hole 30 (including the connection from the supply source to the flow path 44). Is provided with a pressure switch 47 connected to a control device 46 such as a sequencer. When the pressure of the supplied compressed air falls below a predetermined pressure, the control device 46 and the pressure switch 47 operate the pressure switch 47 to operate the control device 46.
The controller 46 performs processing such as blinking a pilot lamp based on the signal, and constitutes a pressure detecting means in the present embodiment.

On the other hand, a passage 48 extending perpendicular to the axis C is formed in the shaft portion 31A of the sheet 31 inserted into the inner peripheral hole 30 when the sheet 31 is mounted on the bearing member 29. Inner peripheral hole 3 of flow path 44 in C direction
It is formed at a position equal to the opening to zero, and serves as opening and closing means in the present embodiment. Therefore, when the sheet 31 rotates with the rotation of the chip 24 during cutting, the passage 48 is continuously formed in a straight line with the flow path 44 at a predetermined rotation position twice as shown by a solid line in FIG. As a result, the flow path 44 is opened to the tip end face of the cutting tool main body 21, and the compressed air flows out, and the pressure in the flow path 44 decreases. In addition, positions other than this rotational position, for example, FIG.
In the position indicated by a broken line in FIG. 3, the flow path 44 is closed by the shaft 31A, and the pressure of the compressed air rises.

In the rotary tool thus constructed, first, the tip 24 is inserted into the recess 33 formed by the tip mounting seat 32 of the sheet 31 and the center axis O thereof is placed in the recess 33.
The cutting edge 27 is rotated if the circularity of the cutting edge 27 and the concentricity between the central axes O and C are accurate. It is possible to make the trajectory an accurate circle. In other words, there are few elements in the combination of members that affect the processing accuracy, and the effects of errors included in these elements can be suppressed. Therefore, extremely high precision is required for molding each member, It is possible to relatively easily obtain high processing accuracy without requiring skill. Moreover, the chip 24 is provided in the recess 3 of the chip mounting seat 32.
3, the clamp piece 40 only needs to contact the circular surface 25 of the chip 24 and press it in the directions of the axes O and C as in the present embodiment.
That is, the assembling accuracy of the clamp piece 40 is
Does not affect the concentricity of the workpiece, it is possible to more reliably and easily obtain high processing accuracy.

In this embodiment, the tip mounting seat 32
Of the cylindrical wall portion 3 that makes an annular circumference around the axis C
Since it is defined by the inner peripheral surface of 2A and the bottom surface 32B of the chip mounting seat 32, a sufficient contact area between the chip 24 and the chip mounting seat 32 can be secured, and the mounting rigidity of the chip 24 can be increased. Vibration at the time of cutting can be prevented, and the processing accuracy can be further improved. In the present embodiment, the cylindrical wall portion 32B is formed so as to make an annular circumference around the axis C as described above.
If the recessed portion 33 is formed in which the wall can be fitted, the wall does not necessarily have to be a complete cylinder surrounding the chip mounting seat.

For example, this wall is constituted by a plurality of arc-shaped plate-shaped walls having the same radius centered on the center axis C, and a peripheral surface connecting the inner peripheral surfaces of these walls and a bottom surface of the chip mounting seat. The chip may be fitted in a disc-shaped recess defined by the above. In this case, a gap is formed in the circumferential direction between the arc-shaped plate-shaped walls. For example, one of the cutting blades 27 of the chip 24 is used up, and the chip 24 is turned over and the other is cut. When using the blade 27, the one cutting edge 2
Even if the weld material or the like is partially adhered to the peripheral surface 26 on the 7 side by the previous cutting, if the adhered area is not so large, it can be positioned in the gap and released. This has the advantage that it is possible to avoid any trouble in sitting.

Regarding the adhesion of the welding material or the like to the peripheral surface 26 of the chip 24, the space between the peripheral surface 26 and the concave surface 23A of the mounting portion 23 facing the peripheral surface 26 is narrow or the peripheral surface 26 slides. If it is movably in contact with the concave surface 23A, there is a possibility that an adhering substance may be caught between them and hinder the rotation of the chip 24. This is the same even when fine chips or the like generated during cutting are caught. However, in the present embodiment, on the other hand, the gap S is formed between the peripheral surface 26 and the concave surface 23A in accordance with the thickness of the cylindrical wall portion 32A of the chip mounting seat 32 of the seat 31. Therefore, even if a welded substance or the like adheres to the peripheral surface 26, the rotation of the chip 24 can be prevented from being interfered,
In addition, fine chips and the like can be discharged from the gap S to prevent biting or the like from occurring. In order to reliably prevent such interference of attached matter and biting of chips, the size of the gap S is set to 0.1 even at the smallest place.
It is desirable to secure about 0.05 to 1.00 mm.

On the other hand, in the present embodiment, the cutting tool body 21
On the other hand, a flow path 44 connected to a pressure switch 47 and a control device 46 via a branch flow path 45 is formed, while a shaft 31A of the sheet 31 that rotates together with the chip 24 has:
A passage 48 that alternately opens and closes the flow passage 44 by the rotation is formed. When the rotation position of the sheet 31 is at a predetermined position, the passage 48 opens in the inner peripheral hole 30 of the bearing member 29. The flow path 44 communicates with the passage 48.
Is released to the outside, the compressed air flows out and the pressure in the flow path 44 decreases, while the flow path 44 is closed at other rotational positions, and the pressure increases. Thus, the pressure switch 47 provided in the branch channel 45 emits a signal twice per rotation of the seat 31 (one time per 1/2 rotation), and accordingly, the control device 46 operates a pilot lamp or the like. When the cutting state is stable and the tip 24 and the sheet 31 are being driven to rotate at a constant speed, the pilot lamp also blinks at a constant interval. When it becomes stable, the blinking of the pilot lamp becomes unstable, and when an unexpected situation occurs and the rotation of the chip 24 is stopped, the pilot lamp remains lit or extinguished.

As described above, according to the present embodiment, it is possible to confirm the rotation of the disc-shaped tip 24 during cutting without relying on visual observation, and therefore, even though the tip 24 is stationary. As a result of erroneously recognizing that the cutting is rotating, the cutting force is prevented from being increased, and a situation where the tip life is impaired due to the local wear of the cutting edge 27 being caused is prevented. As soon as possible, the tip 24, which has been stationary without being noticed, starts to rotate, and further cutting is performed by the cutting blade 27 where such local wear has occurred. As a result, the machining surface precision of the work material is significantly impaired. It is also possible to prevent a situation in which the device is damaged or damaged. Therefore, in the rotary cutting tool according to the present embodiment, excellent processing accuracy can be obtained more reliably, in combination with the above-described effect of fitting and mounting the chip 24 in the recess 33.

The processing by the control device 46 constituting the pressure detecting means of the present embodiment may be such as to perform optical output by blinking of the above-mentioned pilot lamp or to be acoustical to generate an intermittent sound. These may be combined. Further, when the state where the rotation of the tip 24 is stopped is confirmed, a warning may be issued by a siren, a buzzer, a patrol light, or the like, or the control may be performed so that the rotation of the work material is automatically stopped. Furthermore, not only is the rotation state of the chip 24 informed intuitively by light or sound as described above, but also the rotation speed itself of the chip 24 is detected and displayed from the signal transmission interval by the pressure switch 47. Is also good.

Further, the pressure detecting means includes a cutting tool body 2
1, but it is uneconomical to provide each of the cutting tool bodies 21 here. For example, a branch flow path is provided near a connection portion of the supply pipe from the compressed air supply source to the flow path 44. 45 may be provided so that one detecting means on the machine tool side can correspond to all the rotary tools to be replaced. However, especially the pressure switch 47 of this detection means
If the distance from the part where the pressure fluctuates is too far, accurate detection may be hindered.
1, a branch channel 45 is formed in the vicinity of the mounting portion 23, and a pressure switch 47 of detecting means on the machine tool side is formed in the branch channel 45.
May be connected.

Further, various forms other than those described above can be applied to the passage 48 of the sheet 31 formed as the opening / closing means. For example, when a passage opening from the passage 48 orthogonal to the axis C of the sheet 31 to the lower end of the shaft portion 31A is pierced and the flow passage 44 and the passage 48 communicate with each other, the compressed air in the flow passage 44 passes through the mounting hole 28. From the mounting portion 23. In this case, the portion from the inner peripheral hole 30 of the flow path 44 to the distal end surface of the mounting portion 23 may not be provided. Further, a concave portion is formed intermittently in the circumferential direction as a passage in the peripheral surface of the shaft portion 31A of the sheet 31, and when the sheet 31 is at a predetermined rotation position, the flow path 44 from the air supply source to the inner peripheral hole 30 is formed. The flow path 44 extending from the inner peripheral hole 30 to the outside of the cutting tool body 21 may be communicated through the recess.

On the other hand, in the above embodiment, after the chip 24 is seated on the chip mounting seat 32 formed on the sheet 31, the lower surface 40A of the clamp piece 40 provided on the upper part of the mounting portion 23 is moved to the chip 24. The chip 24 is configured to be brought into contact with the circular surface 25, which is a rake face, so that the chip 24 is sandwiched and held between the clamp piece 40 and the sheet 31, but such a configuration is not necessarily required. For example, as in another embodiment shown in FIG. 6, a through hole 51 is formed in the chip 24 along the central axis O thereof,
A clamp screw hole 52 is formed in the seat 31 along the central axis C, the chip 24 is fitted in the recess 33 of the chip mounting seat 32 of the seat 31, and the clamp screw By screwing the screw 53 into the clamp screw hole 52, a head 53A of the clamp screw 53 is formed.
Alternatively, the chip 24 may be attached so as to press the chip 24 against the sheet 31. However, in FIG. 6, the same components as those in the embodiment shown in FIGS. 1 to 5 are denoted by the same reference numerals.

However, even in the rotary cutting tool having such a configuration, the tip 24 is fitted in the concave portion 33 formed by the tip mounting seat 32 of the sheet 31 and its position is determined. If the concentricity of the center axes O and C, that is, the concentricity between the peripheral surface 26 of the tip 24 and the inner peripheral surface of the cylindrical wall portion 32A into which the chip 24 is fitted, is ensured, the rotational trajectory of the cutting blade 27 can be accurately determined. High-precision processing can be performed as a circular shape. Moreover, the clamp piece 40
Is not required, so that the outflow of chips on the circular surface 25, which is the rake face of the chip 24, is not hindered. In addition, in the case of cutting the end face of the work material or cutting the outside diameter of the work material, When the diameter is large, it is possible to prevent the clamp piece 40 from interfering with the workpiece.

In this case, the through hole 51 of the chip 24
In order to prevent the concentricity of the clamp screw hole 52 from affecting the rotation locus of the cutting blade 27, a slight clearance is provided between the outer periphery of the clamp screw 53 and the inner periphery of the through hole 51,
Desirably, the tip 24 is prevented from swaying even when the clamp screw 53 is screwed in, and the clamp screw 53 merely presses the tip 24 against the bottom surface 32 </ b> B of the chip mounting seat 32. In the embodiment shown in FIG. 6, the head 53A of the clamp screw 53 is formed in a countersunk shape, and both ends 51A, 51 of the through hole 51 of the chip 24 are formed.
A is tapered so that the head 53A is buried in the circular surface 25 of the chip 24. However, as described above, the screw 24 is swung in the radial direction with respect to the central axis O by the screwing of the clamp screw 53. To avoid it,
The head of the clamp screw 53 may have a cylindrical head shape with a flat lower surface, and the lower surface may press the circular surface 25 which is the rake face of the chip 24. Further, although omitted in FIG. 6, in this embodiment, FIG.
By providing the flow path 44, the control device 46, the pressure switch 47, the passage 48, and the like as shown in FIG. 5, the rotation of the disk-shaped chip 24 during cutting can be confirmed .

[0036]

As described above, according to the rotary cutting tool of the present invention, it is possible to reduce the factors that affect the processing accuracy and, therefore, to reduce the effects of errors contained in such components. Regarding the member to be mounted on the cutting tool, it is possible to easily obtain high processing accuracy by the rotary cutting tool without requiring a member molded with high precision or requiring high skill in assembling this member. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of a rotary cutting tool according to the present invention.

FIG. 2 is a plan view of the rotary tool shown in FIG.

FIG. 3 is a front view of the rotary tool shown in FIG.

FIG. 4 is an enlarged view of a XX section in FIG. 2;

FIG. 5 is a sectional view taken along line YY in FIG. 4;

FIG. 6 is a cross-sectional view showing another embodiment of the present invention.

FIG. 7 is a plan view showing a conventional rotary tool.

FIG. 8 is a side view of the tip of the rotary tool shown in FIG. 7;

FIG. 9 is a front view of the rotary tool shown in FIG.

FIG. 10 is an enlarged view of a ZZ cross section in FIG. 7;

[Explanation of symbols]

Reference Signs List 21 byte main body 23 mounting portion 24 chip 26 peripheral surface 27 cutting edge 31 sheet 32 chip mounting seat 32A cylindrical wall portion of chip mounting seat 32 32B bottom surface of chip mounting seat 32 33 recess formed in chip mounting seat 32 40 clamp piece 44 flow path 45 branch flow path 46 controller 47 pressure switch 48 path O center axis of chip 24 C center axis of sheet 31 S gap between peripheral surface 26 of chip 24 and concave surface 23A of mounting portion 23

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tomoyoshi Sakamoto 1511 Furamagi, Ishishita-cho, Yuki-gun, Ibaraki Pref. Inside Tsukuba Works, Mitsubishi Materials Corporation (72) Inventor Kiyoshi Hasegawa 2 Takaracho, Kanagawa-ku, Yokohama, Kanagawa Nissan (72) Inventor Toshiichi Otani 2 Takara-cho, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture Nissan Motor Co., Ltd. (56) References Japanese Utility Model No. 2-51005 (JP, U) (58) Field surveyed ( Int.Cl. ⁷ , DB name) B23B 27/12 B23B 27/00 B23B 27/08 B23B 27/14 B23B 27/16

Claims (4)

(57) [Claims] 1. A disc-shaped throw-away tip having a cutting edge formed at an intersection ridge line of at least one of a circular surface and a peripheral surface is detachably attached to a tip of a shaft-shaped cutting tool body. In the rotary tool, at the tip of the tool body, a seat provided with a chip mounting seat that defines a disc-shaped recess is provided rotatably around the center axis of the disc formed by the recess. The throw-away tip is fitted into the recess formed by the tip mounting seat of the seat such that the center axis of the circular surface is aligned with the center axis of the disk formed by the recess, and is fitted around the center axis of the circular surface. The tool body is rotatable and the tool body is in contact with the pressure detecting means.
While a continuous fluid flow path is formed,
Is rotated by rotation of the sheet accompanying rotation of the chip.
Opening / closing means for alternately opening and closing the flow path is provided.
Rotary bytes, characterized in that that. 2. The chip mounting seat is formed in a cylindrical shape with a bottom, and the disc-shaped concave portion is defined by an inner peripheral surface and a bottom surface of a circular cylindrical wall portion of the bottomed cylinder. The rotary bit according to claim 1, wherein the rotary bit is formed. 3. A gap is defined between the peripheral surface of the throw-away tip and the concave surface of the bite body facing the peripheral surface when the throw-away tip is mounted. Claim 1 or Claim 2
Rotary bite described in. 4. A flow path for the fluid, wherein a rotation path of the sheet is provided.
The opening is formed facing the
At a predetermined rotational position, the
The passage that opens the flow path to the outside of the cutting tool body is
4. The rotary cutting tool according to claim 1, wherein the rotary cutting tool is formed as opening / closing means .