JPH0211132Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Industrial Application Field] The present invention relates to a rotary blade used in various materials cutting machines such as chamfering machines, grooving machines, and router machines. [Prior Art] As a type of rotary blade, a cutting edge of a predetermined width is provided on the outer periphery of a rotating body that is assembled to a driving member provided on a base so as to be able to transmit torque. There is a rotary blade that has a plurality of blades spaced apart from each other at a predetermined interval in the direction of rotation of the main body. In this type of rotary blade, as shown in FIGS. 11 and 12, the tip of each cutting edge 1 to 4 is formed into blade portions 1a to 4a over the entire width direction, and the cutting material is It is configured to cut uniformly across the entire width of each cutting edge 1 to 4. Therefore, this type of rotary blade is generally made of steel-based materials such as carbon tool steel, alloy tool steel, and high-speed steel. By the way, cutting tools, including this type of rotary blade, generally require that the cutting edge is always sharp, have excellent wear resistance, maintain hardness even against cutting heat, and are resistant to chipping. It is desirable to have sufficient toughness. For this reason,
Cutting tools are often made of cemented carbide or ceramic instead of steel. In particular, cutting tools made of ceramic have a longer cutting edge life than cutting tools made of cemented carbide, and this tendency is particularly noticeable in high-speed cutting. It has the advantage that it is possible to cut it and the finish of the cutting surface is good. [Problems to be solved by the invention] As described above, ceramic has excellent properties as a cutting tool, so it is extremely effective to use it for the cutting edge of the above-mentioned type of rotary blade. When the cutting edge is made of ceramic, the coefficient of thermal expansion is significantly different from the iron body to which the cutting edge is fixed, and the transverse rupture strength of ceramic is extremely low. If it gets stuck, the same cutting edge may get stuck,
It is difficult to construct a rotary blade due to damage such as cracking or cracking. [Means for Solving the Problems] The present invention has been made to deal with such problems, and includes a rotary blade of the type described above, in which each of the cutting edges is provided with a number of recesses of a predetermined width at predetermined intervals in the width direction. It is composed of a blade base made of a cemented carbide and a large number of blade parts made of ceramic of a predetermined width fixed to each of the recesses of the same blade base, and each blade part of each blade edge and each non-recessed part are adjacent to each other. are located opposite each other. However, in this invention, cemented carbide is WC-
Co series, WC-TiC-Co series, WC-TiC (NbC)-Co
TiC-based cermet, TiC-Ni, TiC-Co alloy, etc., and is formed by sintering and bonding using a known method. Further, in the present invention, ceramic refers to ceramic as a material for cutting tools, and is formed by sintering and bonding aluminum oxide as a main component by a known method. [Operations and effects of the invention] According to this configuration, each blade portion made of ceramic is fixed by brazing or the like to a blade base made of a hardened alloy, which has an extremely small difference in coefficient of thermal expansion compared to the iron main body, and Such a blade base can be fixed to the main body by brazing or the like. For this reason, damage to each blade part due to the difference in thermal contraction between the two blade parts when fixed to the blade base is extremely small, and since the blade parts are dispersed in large numbers in the width direction of the blade base, The difference in thermal contraction between the two is easily absorbed, and damage to each blade portion is further reduced. In addition, when the blade holder is fixed to the main body, the blade holder, which is made of cemented carbide, has extremely high transverse rupture strength, so the blade holder will not be damaged, and each blade part held by the blade holder will be damaged. There's nothing to do. Therefore, in a rotary blade having such a configuration, a large number of ridge-like non-cutting parts corresponding to each non-cutting part are formed when each cutting edge performs cutting, but these non-cutting parts are sequentially cut by adjacent cutting edges. be done. In addition, since the rotational speed of the rotary blade is extremely fast relative to the feed rate of the material to be cut, the uncut portion remaining between each cutting edge is extremely small, and the surface roughness of the machined surface is comparable to that of conventional rotary blades. Kakegami is no different. [Example] The present invention will be explained below based on the drawings.
The figure shows a high-speed vertical shaft type chamfering machine (chamfering machine) equipped with a rotary blade 10 according to an embodiment of the present invention. The sliding chamfering machine is commonly used as a woodworking chamfering machine, and the rotary blade 10 is driven by an electric motor disposed on a base (not shown) and is fitted and fixed to a rotating shaft 22 protruding above a surface plate 21. , same rotation axis 2
It is assembled so that it can rotate integrally with 2. The rotating shaft 22 and the rotating blade 10 are rotatably pressed and supported by a spindle holder 25 that is supported via an arm 24 on a support 23 that is protruded from the base and projects above the surface plate 21. It is designed to be able to rotate at high speeds. In this chamfering machine, the wood to be cut is conveyed along a ruler protruding from a surface plate 21 in a direction penetrating the front and back sides of the paper in FIG. Processing is done. As shown in FIGS. 1 to 4, the rotary blade 10 has an iron main body 11 and two types of four cutting edges 1.
2 and 13, the main body 11 is the rotating shaft 2.
2, and four arm portions 11b to 11e that are positioned at the same interval on the outer periphery of the cylindrical portion 11a and protrude outward like hooks. Each of the arm portions 11b to 11e is formed to have a predetermined width (in the vertical direction), and the pair of arm portions 11 are offset by 180° from each other.
The first cutting edge 12 is fixed to the inner surfaces of the arms b and 11d by brazing, and the other pair of arm parts 11c and 11
A second cutting edge 13 is fixed to the inner surface of e by brazing. Each cutting edge 12, 13 has a blade rest 12a, 13a of a predetermined width (in the vertical direction), and a large number of blade parts 12b, 13b that are fitted and fixed in a number of recesses (grooves 12a1, 13a1) provided in these blade rests 12a, 13a. It is composed of. Each blade stand 12a, 13a is WC-
It is made of Co-based cemented carbide, and each blade stand 12a,
The grooves 12a1 and 13a1 of the blade 13a are formed to have a predetermined width and depth, and are arranged at equal intervals in the width direction of the cutting edges 12 and 13. Each blade stand 12a,
Between 13a, each groove 12a1, 13a1
and the non-groove portions 12a2 and 13a2 are opposed to each other, and the groove portions 12a1 and 13a1 are located slightly overlapping each other. Each blade part 12b, 13b
is a semi-cylindrical piece made of ceramic whose main component is aluminum oxide, and is fitted into each groove 12a1, 13a1 of each blade stand 12a, 13a and brazed with a metal coating formed by surface treatment. ing. The tip of each blade part 12b, 13b is connected to each non-groove part 12a2, 13a of each blade stand 12a, 13a.
2, and each blade part 12b, 13
b and each non-groove portion 13a2, 12a2 are opposed to each other, and each blade portion 12b and 13b slightly overlap. In the rotary blade 10 having such a configuration, the main body 11, the blade stands 12a, 13a, which constitute the rotary blade 10,
The blade portions 12b and 13b have the properties shown in the table below.

[Table] As is clear from the table above, each blade stand 12a, 13
a and each blade part 12b, 13b have approximate thermal expansion coefficients, each blade part 1 of each blade part 12b, 13b
2a, 13a due to the difference in heat shrinkage between these two blade parts 12b, 13b are distributed in large numbers in the width direction of each blade base 12a, 13a, so the difference in heat shrinkage between these two parts is mutually distributed. It is easily absorbed, and damage to each blade portion 12b, 13b is even more likely. Furthermore, when each blade stand 12a, 13a is brazed to the main body 11, each blade stand 12a, 13a is damaged because the transverse rupture force of each blade stand 12a, 13a is large, although the thermal expansion coefficients of the two are greatly different. This will not cause any damage to the blade parts 12b and 13b held by the blade stands 12a and 13a. In the rotary blade 10 having such a configuration, the rotary shaft 2 is driven by the electric motor of the chamfering machine.
2, the material to be cut (wood) is rotated at, for example, 5000 rpm and transported at a transport speed of, for example, 6 m/min.
Cut and chamfer one side. In this case, each cutting edge 12, 13 has a large number of blade parts 12b, 13b and non-grooved parts 12a2, 13a2 alternately, so each cutting edge 12, 13 has a ridge corresponding to each non-grooved part 12a2, 13a2 in the cutting part. A large number of non-cutting parts will be formed, but each cutting edge 12, 1
Since each non-groove portion 12a2 and each blade portion 13b, and each blade portion 12b and each non-groove portion 13a2 in No. 3 are located facing each other, each non-cutting portion is sequentially cut by the adjacent blade edge. Therefore, the total blade length of each cutting edge 12b, 13b of each cutting edge 12, 13 of the rotary blade 10 is smaller than that of each cutting edge of a conventional rotary blade of this type, which reduces cutting resistance and makes cutting easier. This improves the finish of the machined surface because there are fewer cracks due to the grain being against the grain of the wood. In addition, local compressive deformation in the width direction of the material to be cut during cutting is small, improving machinability. By the way, the cutting state of the material to be cut by the rotary blade 10 is as shown in FIG.
The cutting edges 12 and 13 cut the material E at intervals P in the conveying direction. Therefore, minute protrusions e1, e2... remain on the machined surface of the workpiece E at intervals P, but these minute protrusions e1, e2... are ignored in general cutting as shown below. The surface roughness of the machined surface is apparently comparable to that of the conventional method. (1) Cutting interval P is when the rotation speed of the rotary blade is N, the conveyance speed of the material to be cut is F, and the number of cutting edges is n.P=F/(nN) (2) Height of minute protrusions e1, e2... e is when the radius of rotation of the rotary blade is R (3) The operating conditions for the high-speed vertical shaft type chamfering machine are: the rotation radius R of the rotary blade is 50 mm, the rotation speed N is 500 rpm,
When the conveyance speed F of the cut material is 6 m/min Number of cutting edges of the rotary blade 2...P=0.6mm, e=0.001mm Number of cutting edges of the rotating blade 4...P=0.3mm, e=0.0002mm This implementation When cutting is performed under the above conditions using the rotary blade 10 in the example, the height e of the minute protrusions e1, e2, etc. is 0.001 mm, which corresponds to the number of cutting edges 2, and this size is ignored in general cutting. It is a possible value. 6a, b and 7a, b show first and second modified examples 1 of the cutting edges 12, 13 according to the above embodiment.
4 and 15 are shown, and the respective blade parts 12b and 13b in the same embodiment are divided into a semicircular frontal general blade part 14b and a semielliptical frontal blade part 15b with the cutting surface side as the front. May be changed. In addition, Fig. 8 a, b, Fig. 9 a, b, and Fig. 1
Figures 0 a and b show cutting edges 12 and 13 according to the above embodiment.
In each of the cutting edges 16 to 18 of the third, fourth, and fifth modified examples 16, 17, and 18 of these modified examples, each blade part 16b, 17b, and 18b is connected to each blade stand 16a, 17a, It protrudes from 18a by a predetermined length, and a ridge-like groove is formed between each of the blade portions 16b to 18b. In a rotary blade employing such cutting edges 16 to 18, cutting resistance is further reduced, and cutting is performed more easily.

[Brief explanation of drawings]

Fig. 1 is a partial side view showing a part of a chamfering machine equipped with a rotary blade according to an embodiment of the present invention, Fig. 2 is an enlarged plan view of the rotary blade, and Fig. 3 is an arrow shown in Fig. 2. Fig. 4a and b are plan views of each cutting edge, Fig. 5 is a model diagram explaining the cutting state by the rotary blade, and Fig. 6a is a front view showing the first modification of the cutting edge. Fig. 7b is a sectional view in the direction of the arrow, Fig. 7a is a front view showing the second modification of the cutting edge, Fig. 8b is a sectional view in the direction of the arrow, and Fig. 8a is the third modification of the cutting edge. FIG. 9a is a front view showing a fourth modification of the cutting edge, FIG. 10b is a sectional view in the direction of the arrow, and FIG. 10a is a sectional view of the cutting edge. FIG. 11 is a front view showing a fifth modified example of FIG.
The figures are a plan view and a longitudinal sectional view corresponding to FIGS. 2 and 3 showing a conventional rotary blade. Explanation of symbols, 10...Rotary blade, 11...Main body,
11b to 11e...arm portion, 12 to 18...blade tip,
12a to 18a...Blade stand, 12b to 18b...Blade portion, 21...Surface plate, 22...Rotating shaft.

Claims (1)

[Scope of utility model registration request] A cutting edge of a predetermined width extending crosswise to the rotation direction of the main body is maintained at a predetermined interval in the rotation direction of the main body on the outer periphery of a rotating main body that is assembled to a driving member provided on a base so as to be able to transmit torque. In a rotary blade having a plurality of rotary blades, each of the cutting edges has a blade base made of cemented carbide having a number of recesses of a predetermined width at predetermined intervals in the width direction, and a blade of a predetermined width that is fitted and fixed to each of the recesses of the blade base. What is claimed is: 1. A rotary blade comprising a large number of blade parts made of ceramic, and characterized in that each blade part and each non-recessed part of each adjacent blade edge are positioned opposite to each other.