JPS5871008A - Cutting tool - Google Patents

Abstract

PURPOSE:To impove disposability of chips by making the chips whittled by a cutting tool dischargeable in such a condition as being wound in a certain shape like a continuous coil. CONSTITUTION:A cutting tool main body 1 is provided with a chip former 12 of an imitative shape of a flute of a twist drill. The chip former 12 is provided with a rake angle receptacle in parallel with said former so that chips whittled by a main cutting edge 4 are discharged downward to the rear of the cutting tool main body 1. When a workpiece 11 is cut by means of the main cutting edge 4 of the cutting tool main body 1, chips 9 separated from the work piece 11 are forcibly curved by means of the chip former 12 through its wrapping manner, and wound like a coil to be discharged backward.

Description

[Detailed Description of the Invention] Description of the Technical Field The present invention relates to cutting tools, and particularly relates to cutting tools that control the shape and ejection direction of the cutting tool and have improved processability.

佽）Explanation of the prior art The problem of generating, discharging, and disposing of chips during cutting is not just a matter of efficiency in the cutting process9, but also concerns the safety of workers, the quality of workpieces, and the use of machines and tools. 41 for lifespan, damage, etc.!
This is closely related to the improvement in chip control by optimizing the chip shape and ejection direction. t
Under cutting conditions such as small depth of cut and small feed, such as in finishing machining, chip control is even worse, and a solution to this problem is strongly sought after. a) ~ (e
) The cutting tool main body 1 as shown in FIG. There are three types of arc shapes shown in Figure (e). All of these are intended to shred chips appropriately, but the range in which they work effectively is limited depending on the material of the workpiece, cutting conditions, etc.

Here, the types of chip shear forces shown in FIGS. 1 (1) to (41) and the ranges of various numerical values usually taken are shown in a table as follows.

Table 1 (unit 2, ρ only f) In the table, fa represents the feed per rotation (unit ws/rotation).

In FIG. 2, the range in which chips are appropriately cut by the chip breaker shown in FIGS. 1 (1) to (•) is indicated by diagonal lines. Therefore, as is clear from FIG. 2, the cutting conditions under which the chip breaker works effectively are limited, and it can be seen that the chip disposability is poor under low cutting conditions and high cutting conditions.

By the way, as the automation of cutting processes has progressed recently,
It has been proposed to use numerical control (NC) to command the movements and cutting conditions of the machine tool, making it unmanned, but there are other inconveniences, such as the need for a worker to dispose of chips. This is becoming a real problem. On the other hand, when cutting ductile materials such as stainless steel, steel, and aluminum, 4 cuts]
In some cases, the waste forms into long strips11, and various tool shapes have been devised to shred it, but the problem has not yet been solved. When attempting to shred a chip, the force of the chip is struck by the cutting chip, often resulting in damage and shortening the tool life. It is impossible to predict the situation, and as a countermeasure, we are often forced to take a reactive approach.Ninth, as the automation of machining itself is rapidly progressing, it is difficult to artificially create the shape of chips and eject the chips. There was a strong desire for a cutting tool that could control its direction.

In order to better understand the present invention, a conventional example and an experimental example will first be described with reference to FIGS. 3 to 8. Line 3 is an example of a conventional cutting tool (bit), and is the same as that shown in FIG. 4 major cutting edges, J minor cutting edges, 6 line rake face, Fa main flank face, 8Fi minor flank face. Figure 4 is a partial perspective view showing the twist drill 3 used for enlarged drilling. , main cutting edge 4, -cutting edge 5, rake face 6, main flank r1, secondary flank 8, etc. Must be included as a cutting tool 1! It can be seen that it has the same shape as Pi and To in the 豐 element line curve description, and although the shape line is quite different, it is functionally similar to Jin. Fig. 5 is a schematic diagram showing the state of the twist drill during drilling into the workpiece 11, in which the chips generated by the main cutting edge 4 at the tip are continuously passed through the flute 10 in the upper direction of the twist drill. It can be seen that it is being discharged.

Figure 6 is a cross-sectional view showing the state of the cut 9 which is restrained by the left and right flutes 10 and the inner wall of the hole of the workpiece 11.

Now, in reality, there are many chips that are continuously discharged along the flute of a twist drill and in good condition. , Precision Yokoyari, Volume 43, No. 4, 9.427-43
2) (April 1977), it is said that the cutting performance of the twist drill is extremely good for two-dimensional cutting with a cutting tool with a rake angle of 20° and 11° when the hole is shallow9. It has been revealed that it has a reasonable shape as a tool. Therefore, we focused on the cutting performance, shape, and evacuation properties of the twist drill, and conducted an experiment to use it as a single odor for turning. As shown in Figure 5, the shape of the chips obtained in this experiment is a continuous nine-coil shape mainly consisting of a conical spiral shape] and varies from low to relatively high cutting conditions. Unexpected chips were generated and were discharged after passing through the flute 10. Among the cutting conditions shown in Fig. 8, the horizontal axis is the feed f1, and the vertical axis is the depth of cut d. The diagonal line indicates the area where the cutting process occurs.As can be seen from this figure, a normal cutting tool can cut a continuous conical spiral shape under a wide range of cutting conditions as shown in Figure 8. It is difficult to discharge waste in a fixed direction. (e) Purpose of the Invention The present invention has been made in order to eliminate the above-mentioned drawbacks.
The purpose of the present invention is to provide a cutting tool with improved chip disposal performance that can produce chips in a continuous coiled shape and control the discharge direction as desired.

(d) Embodiments of the Invention Below, embodiments of the present invention will be described with reference to the drawings. FIG. 9 is a perspective view showing the main parts of the cutting tool in the first embodiment of the present invention. In this embodiment, as shown in FIG. , the structure is as follows. In this case, a parallel rake angle λ is provided so that the chips cut by the main cutting edge 4 of the chip former 12 are discharged to the rear and lower part of the tool body 1.

Figure 10 shows a partial cross-sectional view of the vicinity of the cutting edge of the cutting tool used in a cutting comparative test focusing on chip control performance.
Figure 1θ (1) The chip former of the present invention is shown in Figure 1O (
b) Fi indicates a type of conventional general chip breaker 6 The specifications of both are shown in Table 2, ' Table 2 As shown in Table 1, both shapes have tcm * rake angle ρ #
i=30° Hirin, side edge angle (not shown) 15°, front cutting edge angle (WA not shown) a5°, radius of curvature of rake face Rt
It is unified to i1.25■, groove direction and welfare 3.0-. Now, one of the features of the present invention is that the angle 0 formed by the inscribed circle C of the chip f7 ohm and the contact arc PIIP with the chip former is 90° or more and is less than 90° compared to the conventional chip breaker. It's bigger in comparison. In addition ? Even if the cross-sectional shape of the tube former is an elliptical special curve in the bath, it is treated as a substantially circular shape and the same applies as above. -1+A 4[line portion may be provided in the portion of the chip former near the main cutting edge 4.

Here, the material of the cutting blade and chip former is steel, high-speed steel (high-speed machining steel), and softer cemented carbide, such as fine-grain alloy and P30 to 4 of the JIB part a designation number.
0. M30~40. Approximately 3O is suitable for this purpose, and coated grades are also suitable.

Next, the operation of the excellent cutting tool constructed as described above will be explained.

FIG. 11(a) is a cross-sectional view schematically showing the state of cutting by the chip former IIK of the cutting tool. Because the chip former 12 wraps around it, it is forcibly curved, and the curvature radius line of the cut at that time has a value close to that of the aforementioned chip former's curvature diameter blade, but according to experiments, the material of the workpiece It varies somewhat depending on the cutting conditions.

FIG. 11(b) is a cross-sectional view showing the state of chip generation by the conventional chip breaker 2.
In addition, the flow direction of chips also varies depending on the shape of the chips. Even if chips are generated in the shape of a zero circular arc, the flow direction of the chips (
The radius of curvature of the chip breaker 2 is considerably larger than the radius of curvature 12 of the tatami. Since the purpose of this company's chip breaker is essentially to shred chips, it is difficult to wrap the chip and forcibly curve it, like the chip former 120 of the cutting machine in this example. This is due to not doing so. However, when cutting workpieces, especially materials such as highly ductile copper alloys, stainless steel, etc., it is better to use a continuous tt instead of forcibly cutting the whirling scratches into small pieces. ,
(Cut is determined by the direction of the chip former, such as a small continuous coil shape.) The direction of ejection of chips can be adjusted to the safe side for the operator, the direction that does not contact the finished surface of the workpiece, the direction of the chip can, etc. Is it better to control it in a good direction? Even though the cutting edge itself can be used with a conventional cutting tool that uses a chip breaker to shred chips, if the breaker is damaged by being hit by chips. However, the shape of the chips and the flow direction of the chips change constantly, which often makes them unusable. However, in the cutting tool according to this embodiment, the outflowing force of the four cuts is used to wind it into a coil in a smooth circular arc, so the damage to the chideformer is slight.

FIG. 12 is a perspective view showing the state of cutting by the cutting tool of this embodiment], in which chips 9 generated in a continuous coil shape by the chip former 12 pass through the chip former 12, and It is being ejected in the same direction.

FIG. 1 is a diagram illustrating the generation area of continuous coiled scars by the cutting tool of this embodiment and the conventional cutting tool with the specifications shown in FIG. 10 in relation to cutting conditions; The entire range of the L experiment with the 1″@cutting tool of this example, that is, the feed fuO,
01 dragon/rotation to 0.1 simple/rotation, depth of cut 0.05
Continuous coiled chips were generated in a wide range from 1.0 to 1.0, whereas the conventional cutting tool shredded 9 chips in areas other than the shaded area. In other words, conventional cutting tools produced both continuous coiled chips and shredded chips within the experimental conditions, resulting in variations in chip shape and poor processability. -O) Modifications Next, other embodiments of the present invention will be described.

FIG. 14 is a perspective view showing the main parts of the second embodiment of the present invention. In this embodiment, as shown in FIG. In this case, the hole-shaped chip former 1B111 is more appropriately called a chip guide hole. Fig. 15 The example shown in Fig. 14 is displayed using trigonometry, and the angular relationship of the cutting chip guiding hole IS is shown, so the angle of the cutting chip guiding hole IS is defined in three dimensions. α in the figure.

All you need to do is decide on two of β and r.As a result of actual experiments, the values of α and β are 10 to 70° for α and 5 to 10 for β.
It was found that the cutting angle was in the range of 5°, and that continuous coil-shaped cuts (zigzag cuts) passed through the guide hole 13 and were discharged.

However, the cutting conditions, the cutting edge part and the above-mentioned cutting chip guide hole 1-
3, especially when using a part of the ISO guide hole ISO opening as a cutting edge, the shape of the rake face is superimposed, and the surface transitioning from the cutting edge to the hand guide hole is smooth. A curved surface improves the flow of chips.

FIGS. 16 to 26 show third to thirteenth embodiments of the present invention, respectively, and the third to eighth embodiments show cases in which the system is slow-out and slow-down. In the third embodiment shown in FIG. 162, a total of eight chip formers 12 are provided on the upper and lower surfaces of the line. With such a structure, as the cutting blades wear out, unused cutting blades are sequentially determined. In addition, in the fourth embodiment shown in FIG. 17, which shows a rounded rectangular parallelepiped for fracture*a shape comparison, the uniform radius R of the 4-chip former is gradually changed to R',
It has a nine configuration with a certain width in the chip discharge direction, and in the fifth embodiment shown in FIG. Both ends of one chi, f former become cutting edges.

The sixth example line No. 18111 shown in FIG. 19! Throwaway chip f14 with Chizzo former of the type shown in IK
It is composed of 9 parts in relation to the tool holder 1. ・Cut 9, throw away, cut 14, and 14! 12, and then passes through a groove 15 provided in the tool holder 1' and connected to the chia dea ohmer 12, and is continuously discharged to the rear and lower part of the tool holder. Second
In the seventh embodiment shown in Fig. 0, a throwaway insert ffi, de141/C chip f7° orma11 is provided, and its cross-sectional shape gradually changes and is reversed on the opposite side. 41 By making it into a shape like this 4
The main cutting edge 4 at any of the eight locations can generate and eject good chips.In the eighth embodiment shown in Fig. 2i, although it is a throw-away tip for a vertical insert lid, FIG. 9 is a perspective view of an improved embodiment with a cutting edge and a chip former in relation to a tool holder II, in which chips are removed by an inclined rake face 18, a chip former 12, and a chip former provided on the upper surface of the tool holder; It passes through the groove 15 and is discharged. #Groove 15 line Δide shape may be used.

The above explanation line takes as an example the case where the chip former and the cutting edge are combined into the same indexable insert or cutting tool. The 22nd embodiment shows the case where the frame-divided configuration is adopted in the 9th to 13th embodiments shown in ilK.
! The ninth embodiment shown by EIK is a throw-away chair with a flat scooping surface! Alternatively, a plate 20 made of carbide or steel, on which the chip former 12 is formed, is mounted on the upper surface of the cutting tool 1. In the embodiment No. 1O shown in FIG. 23, an inscribed circle C The ends are shaped so that the arcs of the two are connected smoothly. By using these plates 2o, a conventional chip breaker can be installed during flat forming, and a skin cutting tool can be improved to be a better companion with a chip former. As a means of connecting the plate 2o, the indexable tip or Fi, and the cutting tool 1, there is a hole 16 provided in the center of both, in addition to brazing or pressure welding from the top surface of the plate.
A known technique such as fastening with a hollow screw using ζ
In the embodiment 1.1 shown in FIG.
The plate 2o is placed on top of the l4 and the two form a chip former. 12 shown in Figure 25
In this embodiment, it is constructed in relation to the cutting tool holder 1'. In FIG. 25, the plate 2o is restrained on two sides 81 and 81 by the bite holder and also restrained and fixed by the tightening pin 11. In the thirteenth embodiment shown in FIG. 26, an indexable insert 14 provided with chip guiding holes 13 is constructed in relation to a cutting tool holder 1', and inclined through holes provided at the four corners are used to guide chips. In addition to acting as the guide hole 11, a hole 21 connected to the chip guide hole actually involved in cutting is drilled through the tool holder 1', and chips are discharged from the lower part of the tool holder. .

In addition, when the container for storing chips is relatively far away, a flexible /# ID 22 with a diameter of 4 or more in diameter of the chip guide hole IJ is provided in the 74-item holder 1' through hole JZK. To smooth the flow of chips on the connected top/
! You can also suck it from the outlet side of the f22.

←) As explained in detail about the invention, the present invention generates continuous coil-shaped chips, and a chip former or a chip guide hole is provided near the cutting edge so that the direction of discharge of the chips is determined. As a result, the following effects can be obtained.

(1) Chip former or wire cutter 9 Cuts a chip guide hole (rounding for chips to pass through, direction safe for the operator, convenient direction for storing chips, direction far away from the machined internal wire) Tools and machines It is possible to change the direction in which chips are ejected depending on the purpose, improving safety, improving chip disposal efficiency, and improving machined surface quality. Direction line for scrap ejection Stable and constant direction without any change in the direction during processing ゛
Since the process is carried out from -m, the container is used for chip disposal, etc.

These effects are particularly important when processing ductile materials such as copper, aluminum, and stainless steel.

(2) Since the chips are in a continuous coil shape with a percentage control, there is no change in the shape of chips during machining or scattering of shredded chips, which is the case with conventional machining. Improves efficiency.

The outer diameter of the chips is the P3 tangent diameter of the chip former,
Alternatively, since Fi has a value approximately equal to the inner diameter of the guide hole, it is also possible to connect a nodule or tube to facilitate smooth transportation of chips within the pipe.

(3) Compared to conventional cutting tools, it is possible to generate continuous coiled chips with the same shape over a wider range of cutting conditions. In other words, the need to restrict cutting conditions in order to maintain a constant shape without cutting is reduced as in the past, and the same cutting tool can be used to cover conditions from high to low cutting conditions, resulting in more efficient machining. I can do it.

(4) In conventional cutting tools equipped with chip breakers, the chip breakers are damaged due to being lost in chips.1. In many cases, the tool became unusable, but with the present invention, the force of the flow of chips is used to smoothly wind the tool into a coil, resulting in less damage to the tool and a longer tool life.

[Brief explanation of the drawing]

Figure 1 is a partial sectional view showing the shape of a conventional chip breaker, Figure 2 is a diagram showing the effective range of an enlarged chip breaker,
Figure 3 is a perspective view showing a conventional cutting tool, Figure 4 is a perspective view of an L twist drill, Figures 5 and 6 are sectional views showing the cutting state of the twist drill, and Figure 7 is a perspective view showing the cutting state of the twist drill. 8 is a diagram showing the generation range of continuous conical and spiral chips. FIG. 9 is a perspective view showing the main part of the first embodiment of the present invention, and FIGS. 10 and 11.
The figure shows the same example. Comparative cross-sectional view of the breaker, Figure 12 is a diagram showing the cutting state by the chip former of the same example, Figure 13 is a diagram showing a comparison of the effective range of the chip former and the chip breaker in the same example, Figure 14 FIGS. 26 to 26 are the second to thirteenth embodiments of the present invention.
FIG. 1...Cutting tool, 4 bits, 1'...Bite holder, 2...Chip breaker, 3...Twist drill,
4... Main cutting edge, 5... Minor cutting edge, 6... Rake face,
1...Main flank surface, 8...Sub-flank surface, 9...Chip, 10...Flue), 11'--Workpiece, 12
...Chip former, 13...Chip guiding hole, 1
4... Throw away! , 15...Groove connected to chip former, 16...Central hole, 17...Tightening pin, 18...Slanted rake surface, 19...Shim, 20...Plate, 21... ... Hole connected to the chip guiding hole, 22 ... Rigidity, f ... Feed, d ... Depth of cut, ρ ... Vertical rake angle, R, R' ... Rake face or chip former Radius of curvature, ω... Groove width, C.
...Inscribed circle, P. Ps...Both ends of the contact arc, θ...Angle formed by PlrPl, O...Center of the inscribed circle, ■...Cutting speed, α, β
. γ...Angle of the chip guiding hole, λ...Parallel rake angle of the chip former, S3...Restricting surface of the tool holder, φ...Diameter of the chip guiding hole. Applicant's representative Patent attorney Takehiko Suzue fig #I2 remaining f (m 10h) Fig. 7 $88 -1 Fig. 14 116 BEl' H17yJ@M8 Fig.
ff9 Sen J821 Figure 5 Figure 22 Figure 23 Vagina

Claims (2)

[Claims] (1) A chip former having a substantially semicircular cross-sectional shape that generates chips in a continuous coil shape and determines the discharge direction of the chips is provided near the cutting edge of the cutting tool body. Characteristic cutting tools. (2) A through hole is provided near the tip of the cutting edge of the cutting tool body as a chip guiding hole to generate chips in a continuous shape and to determine the direction of discharge of the chips. cutting tools.