CN106346030B - A kind of bicircular arcs turning insert - Google Patents

Abstract

A double-arc turning blade belongs to the technical field of turning tools. The purpose of the invention is to provide a double-arc turning blade which can improve processing efficiency and surface smoothness, and can prolong service life. Any top corner of the upper surface of the cutter body is provided with an embedding groove that matches the tip insert, and the tip insert is tightly embedded in the embedding groove of the cutter body. The side 1 and side 2 of the turning blade are located at the cutting corner. On both sides, the tip insert has a cutting section of the tip, and the cutting section of the tip is processed with a negative chamfer; the cutting corner includes curved surface 1, curved surface 2, smooth surface and three cutting edges, and the three cutting edges are set on the tip At the lower edge of the negative chamfer of the insert, the three cutting edges are straight cutting edge, arc cutting edge 1 and arc cutting edge 2, side 1 is tangent to surface 1, surface 1 is tangent to surface 3, and surface 1 is tangent to surface 1. The third and the smoothing surface are connected through a smooth transition surface, and there is an included angle between the smoothing surface and the second side. The invention is suitable for finishing turning.

Description

A double-arc turning blade

technical field

The invention relates to a turning insert, which belongs to the technical field of turning tools.

Background technique

The wiper blade can repair the residual metal left on the machined surface during the tool pass, reducing the surface roughness. The wiper blade must be ground straight and clean. When installing, it should be kept parallel to the feed direction. The wiper edge should not be too large, as it will increase the radial resistance of cutting and easily cause vibration. And only when the rigidity of the process system such as the workpiece, tool, fixture and machine tool is good, the use of the wiper can achieve better results. The length of the wiper blade is generally 1.2 to 1.5 times the feed rate. The wiper blade adopts a feed rate twice that of the standard blade, and the same surface finish can still be obtained. The advantage of the wiper edge is "halving the machining time and doubling the surface quality".

The wiper edge is between the main cutting edge and the minor cutting edge. It is the extreme form of the minor cutting edge. The wiper edge can improve the impact resistance of the tool tip and improve the processing efficiency. Common wiper blades are straight and arc-shaped. The arc-shaped wiper blade, the larger the radius of curvature, the higher the finish of the machined surface and the durability of the tool, but it will also increase the grinding force, easily generate vibration, and reduce the processing efficiency. Long-term use of the tool is easy to damage, which affects the use of the tool life.

Contents of the invention

The object of the present invention is to provide a double-arc turning blade that can improve processing efficiency and surface finish, and can prolong service life.

Realize above-mentioned object, the technical scheme that the present invention takes is as follows:

A double-arc turning blade, the turning blade is composed of a cutter body and a cutter tip insert, the middle part of the cutter body is provided with a tool rod installation hole, the horizontal section shape of the cutter body is polygonal, and the upper part of the cutter body Any corner of the surface is provided with an embedding groove that matches the blade tip insert, and the blade edge insert is tightly embedded in the embedding groove of the cutter body. The sides of the turning blade include side one, side two and The cutting corner, the side 1 and the side 2 are located on both sides of the cutting corner, the cutting edge insert has a cutting edge cutting section, and the cutting edge cutting section is processed with a negative chamfer;

The cutting corner includes curved surface one, curved surface two, smoothing surface and three cutting edges. The three cutting edges are arranged at the lower edge of the negative chamfer of the tip insert, and the three cutting edges are respectively straight cutting edge, arc cutting edge one and arc cutting edge two, the radius of curvature of the arc cutting edge one is larger than the curvature radius of the arc cutting edge two, the side surface one is tangent to the curved surface one, the The curved surface 1 and the curved surface 2 are tangent, the curved surface 2 and the smoothing surface are connected by a smooth transition surface, there is an included angle between the smoothing surface and the side surface 2, and the curved surface 1 corresponds to the arc cutting edge 2, The curved surface 2 corresponds to the arc cutting edge 1, and the smooth surface corresponds to the straight cutting edge;

The intersection point between the arc cutting edge 1 and the arc cutting edge 2 is the highest point, the arc cutting edge 2 intersects with the center line of the cutting corner, and the arc cutting edge 2 is asymmetric to the cutting angle The center line of the cutting corner is set, and the highest point is set near the center line of the cutting corner;

The radius of curvature of the arc cutting edge 1 is 6 to 10 times that of the arc cutting edge 2, and the centers of the curvature radii of the arc cutting edge 1 and the arc cutting edge 2 are at the same point as the highest point. on a straight line.

The beneficial effect of the present invention relative to prior art is:

The double-arc turning blade of the present invention has the characteristics of increasing the cutting width, improving the processing efficiency, reducing the surface residual height and increasing the durability of the tool. The double-arc turning blade of the present invention is the same as the conventional turning blade Under the condition of cutting parameters, the present invention can increase the processing efficiency by about 3 times, and reduce the surface residual height value by about 3 times. The invention is suitable for finishing turning, and is suitable for finishing turning relatively hard materials, such as hardened bearing steel, high-temperature alloy and the like.

Description of drawings

Fig. 1 is the perspective view of double-arc turning blade of the present invention;

Fig. 2 is the local plan view of double-arc turning blade tip of the present invention;

Fig. 3 is a top view of the relative positions of the double-arc turning blade and the workpiece when the outer circle is turning hardened bearing steel;

Figure 4 is a top view of bearing steel processed by an 80° rhombic blade with a radius of 0.8 mm in the arc of the tool tip; W1 is the cutting width of a standard 80° rhombic blade with a radius of 0.8 mm in the arc of the tool tip;

FIG. 5 is a top view of bearing steel processed by the double-arc turning blade 8 of the present invention, and W2 is the cutting width of the double-arc turning blade 8 of the present invention.

Among them, straight cutting edge 1, arc cutting edge 1, arc cutting edge 2, 3, tip insert 4, tool holder mounting hole 5, cutter body 6, 80°diamond insert 7, double arc turning insert 8, Side I, curved surface II, curved surface II III, smooth surface IV, side II V, upper surface VI, lower surface VII, negative chamfer VIII, cutting corner M.

Detailed ways

Specific embodiment one: as shown in Fig. 1 and Fig. 2, a kind of double-arc turning blade, this turning blade is made up of two parts of cutter body 6 and knife tip insert 4, and the middle part of described cutter body 6 is provided with cutter Rod installation hole 5, the horizontal cross-sectional shape of cutter body 6 is polygonal, and any apex of the upper surface VI of cutter body 6 is provided with the embedding groove that matches with blade tip insert 4, and described cutter tip insert 4 Tightly embedded in the embedding groove of the cutter body 6, the side of the turning blade includes a side I, a side two V and a cutting corner M, and the side I and the side two V are located on both sides of the cutting corner M, The blade edge insert 4 has a blade edge cutting segment, and the blade edge cutting segment is processed with a negative chamfer VIII;

The cutting corner M includes a curved surface II, a curved surface III, a smoothing surface IV and three cutting edges, and the three cutting edges are arranged at the lower edge of the negative chamfer VIII of the tip insert 4, The three cutting edges are straight cutting edge 1 (the length of which is related to the feed rate and plays the role of wiping the machined surface), arc cutting edge one 2 and arc cutting edge two 3, and the arc cutting edge one The radius of curvature of 2 (for chip removal edge) is greater than the radius of curvature of arc cutting edge 2 3 (arc cutting edge 2 3 is a transition edge, which does not participate in cutting, but can enhance the strength of the tool tip), and the side I and The curved surface II is tangent, the curved surface II and the curved surface III are tangent, the curved surface II III is connected with the smoothing surface IV through a smooth transition surface, and there is a gap between the smoothing surface IV and the side surface II V. For the included angle, the curved surface 1 II corresponds to the arc cutting edge 2 3 , the curved surface 2 III corresponds to the arc cutting edge 1 2 , and the smoothing surface IV corresponds to the straight cutting edge 1 .

As shown in FIG. 1 , the upper surface VI of the cutter body 6 is arranged parallel to the lower surface VII; the straight cutting edge 1 is kept parallel to the feed direction during the cutting process.

In order to facilitate the installation of the knife rod, the upper and lower edges of the knife rod mounting hole 5 are all provided with chamfers.

Specific embodiment two: as shown in Fig. 1 and Fig. 2, a kind of double-arc cutting insert described in specific embodiment one, the intersection point between described arc cutting edge one 2 and arc cutting edge two 3 is The highest point, the arc cutting edge 2 3 intersects with the center line G of the cutting corner M, and the arc cutting edge 2 3 is asymmetrically set to the center line of the cutting corner M, and the highest point is set at the cutting Near the center line of corner M (the points on the two arc cutting edges cannot exceed the highest point).

Specific embodiment three: as shown in Figure 1, a kind of double-arc turning blade described in specific embodiment one, the value range of the negative chamfer VIII width is 0.15-0.24mm, the negative chamfer VIII angle value The range is -5°～-25°. The effect is: If the chamfer width and chamfer angle are too large, the cutting force generated during the cutting process will be too large, and the vibration generated during machining will also increase, which will affect the quality of the processed surface. If the value is too small, the effect of chamfering is not obvious.

Specific embodiment four: as shown in Figure 1, a kind of double-arc turning blade described in specific embodiment one, the thickness of described turning blade is 4.76mm (standard parameter), the thickness of knife tip insert 4 is turning blade 1/3 to 1/4 of the thickness (in order to enhance the strength of the tip insert 4).

Embodiment 5: As shown in Fig. 1 and Fig. 2, a double-arc turning insert described in Embodiment 1, 2, 3 or 4, the length range of the straight cutting edge 1 is 0.36-0.45mm .

Specific embodiment six: as shown in Fig. 1 and Fig. 2, a kind of double-arc turning insert described in specific embodiment two, the radius of curvature of the arc cutting edge one 2 is the curvature of the arc cutting edge two 3 6 to 10 times the radius (in order to increase the cutting width), the center of the radius of curvature of the arc cutting edge 1 2 and the arc cutting edge 2 3 is on the same straight line as the highest point (in order to make the arc Cutting edge one 2 and arc cutting edge two 3 ensure tangency, that is, smooth transition).

Embodiment 7: As shown in FIG. 1 , for the double-arc turning blade described in Embodiment 1, the included angle between the smoothing surface IV and the side surface 2 V is 175°.

Embodiment 8: As shown in Figure 1, a kind of double-arc turning blade described in Embodiment 1, the turning blade is made of any one of cubic boron nitride material, diamond, ceramics, and hard alloy material or the cutter body 6 is made of cemented carbide material, and the tip insert 4 is made of cubic boron nitride material.

Embodiment 1: As shown in Figure 1 and Figure 2, when carrying out finish turning, the maximum feed rate is 0.3mm/r, so the length of the straight cutting edge 1 of this embodiment is selected as 0.4mm, and the straight cutting edge 1 is cutting It plays the role of wiping the processed surface. When turning, try to ensure that the straight cutting edge 1 is parallel to the machined surface, so as to ensure that the straight cutting edge 1 works. The arc cutting edge 12 participates in cutting as a chip removal edge, and its radius of curvature is larger, the cutting width is larger, and the processing efficiency is higher. The arc cutting edge 2 3 is not involved in cutting as a transition edge, and plays a role in strengthening the edge strength, and the arc cutting edge 2 3 can also adopt a straight line form.

Embodiment 2: as shown in Fig. 1 and Fig. 2, a kind of double-arc cutting blade, the length of straight cutting edge 1 in the present embodiment is 0.4mm, and the radius of curvature of arc cutting edge-2 is 3.8mm, and the circle The radius of curvature of the arc cutting edge 2 3 is 0.5mm, the diameter of the tool bar mounting hole 5 is 5.16mm, the chamfering edge of the tool bar mounting hole 5 is 0.2x45°, the chamfering width of the turning blade is 0.2mm, and the chamfering angle is -25°.

Embodiment 3: A double-arc turning blade. The double-arc turning blade in this embodiment adopts an 80° rhombus structure, as shown in FIG. 5 . Fig. 4 is a top view of machining bearing steel with an 80° rhombic blade with a radius of 0.8 mm at the tip of the blade. The type of tool holder used by the two kinds of turning inserts is DCLNR 2525M12, and the main declination angle of the installation is 95°, and the secondary declination angle is 5°. From Fig. 4 and Fig. 5, it can be clearly seen that in one feed, the cutting width W2 of the double-arc turning blade of the present invention is obviously greater than the cutting width W1 of the 80° rhombus blade of the arc radius of the knife tip, and the double-arc turning blade of the present invention The cutting width W2 of the turning blade is about 3 times that of the 80° rhombic blade cutting width W1. Under the same surface quality requirements, the processing efficiency is about 3 times that of the 80° rhombic blade. Compared with the 80° rhombic blade, the present invention has smaller main deflection angle, smaller residual area height of the processed surface, lower roughness value and better processed surface quality. At the same time, the smaller entering angle can improve the strength of the tool tip, the heat dissipation performance is good, and the thermal damage is reduced.

The double-arc turning insert of the present invention has negative chamfering, and the negative chamfering includes two parameters: chamfering width and chamfering angle. The width of the chamfer is related to the amount of feed. When the width of the chamfer is greater than the amount of feed, it will form spiral chips that are not conducive to cutting. , safety, and the surface quality of the workpiece are not good. The width of the chamfer should be smaller than the feed rate to form a C-shaped chip that is beneficial to cutting. During finishing, the feed rate does not exceed 0.3mm/r, so the chamfer width should not be greater than the feed rate, and its value range is 0.15-0.24mm, and the value range of the chamfer angle is -5°～-25°. The thickness of the turning blade is 4.76±0.013mm, and the thickness of the cutting blade insert 4 should be 1/3～1/4 of the turning blade thickness, so as to ensure the strength of the cutting edge insert 4.

In Figure 3, a is the centerline of the bearing, ap is the cutting depth, f is the feed direction, and bp is the cutting width. In actual processing, the cylindrical hardened bearing steel is installed on the three-jaw chuck of the machine tool, and it rotates counterclockwise around the center line a of the bearing. The turning blade moves along the feed direction f, and the main cutting edge is in a certain clamp with the feed direction. Angle, the included angle is the main declination angle Kr. The angle between the secondary cutting edge and the opposite direction of feed is the secondary deflection angle Kr'.

The cutter bar used in the double-arc turning blade of the present invention is a standard diamond-shaped cutter bar DCLNR 2525M12, the primary deflection angle Kr=95°, and the secondary deflection angle Kr'=5°.

Claims (6)

1. A double-arc turning blade, the turning blade is composed of a cutter body (6) and a blade tip insert (4), and the middle part of the cutter body (6) is provided with a tool holder mounting hole (5) , the shape of the horizontal cross-section of the cutter body (6) is polygonal, and any corner of the upper surface (VI) of the cutter body (6) is provided with an embedding groove matching the blade tip insert (4). The pointed insert (4) is tightly embedded in the embedding groove of the cutter body (6). The side of the turning blade includes side one (I), side two (V) and cutting corner (M). The side one (I) and side two (V) are located on both sides of the cutting corner (M), and the tool tip insert (4) has a tool tip cutting section, and the tool tip cutting section is processed with a negative chamfer (VIII ); characterized in that: The cutting corner (M) includes a curved surface (II), a curved surface (III), a smooth surface (IV) and three cutting edges, and the three cutting edges are set on the tip insert (4) At the lower edge of the negative chamfer (VIII), the three cutting edges are straight cutting edge (1), arc cutting edge one (2) and arc cutting edge two (3). The radius of curvature of one (2) is greater than the radius of curvature of the arc cutting edge two (3), said side one (I) is tangent to curved surface one (II), said curved surface one (II) and curved surface two (III) ) is tangent, the curved surface 2 (III) and the smoothing surface (IV) are connected by a smooth transition surface, and there is an included angle between the smoothing surface (IV) and the side surface 2 (V), and the curved surface 1 (II ) corresponds to the arc cutting edge two (3), the curved surface two (III) corresponds to the arc cutting edge one (2), and the smooth surface (IV) corresponds to the straight cutting edge (1); The intersection point between the arc cutting edge one (2) and the arc cutting edge two (3) is the highest point, and the arc cutting edge two (3) intersects the center line of the cutting corner (M) , and the arc cutting edge two (3) is set asymmetrically to the center line (G) of the cutting corner (M), and the highest point is set near the center line of the cutting corner (M); The radius of curvature of the arc cutting edge one (2) is 6 to 10 times the curvature radius of the arc cutting edge two (3), and the radius of curvature of the arc cutting edge one (2) and the arc cutting edge two (3) The center of the radius of curvature is on the same straight line as the highest point. 2. A double-arc turning blade according to claim 1, characterized in that: the width of the negative chamfer (VIII) ranges from 0.15 to 0.24 mm, and the range of negative chamfer (VIII) angles -5°～-25°. 3. A double-arc turning blade according to claim 1, characterized in that: the thickness of the turning blade is 4.76mm, and the thickness of the tip insert (4) is 1/3-1 of the thickness of the turning blade. /4. 4. A double-arc turning insert according to claim 1, 2 or 3, characterized in that: the length of the straight cutting edge (1) ranges from 0.36 to 0.45 mm. 5. A double-arc turning insert according to claim 1, characterized in that: the angle between the smoothing surface (IV) and the second side (V) is 175°. 6. A kind of double-arc turning blade according to claim 1, characterized in that: said turning blade is made of any material in cubic boron nitride material, diamond, ceramics, and cemented carbide; Or the cutter body (6) is made of hard alloy material, and the cutter tip insert (4) is made of cubic boron nitride material.