JP5056019B2 - Blade replacement type cutting tool - Google Patents

Description

  The present invention relates to a blade part exchangeable cutting tool.

  Patent Documents 1 to 5 disclose a method of fixing a blade part and a tool body in a blade part exchange-type cutting tool.

JP 7-276127 A JP 2005-34939 A Japanese National Patent Publication No. 11-500967 Japanese translation of PCT publication No. 2002-501441 Japanese Patent No. 2656949

Patent document 1 is disclosing the structure which passes a volt | bolt through the through-hole provided in the blade part, and fixes with a tool main body. However, in this configuration, the through-hole greatly reduces the strength of the blade portion, and the shape of the blade portion is restricted, so that there are disadvantages that a complicated shape such as a ball end mill cannot be formed. Patent document 2 is disclosing the structure which forms a screw in the edge part of blade part itself, and is screwed together with a tool main body. However, in this configuration, since the screw is formed on the blade portion made of a hard material, the processing is difficult and high accuracy cannot be achieved, and the stress is concentrated in the valley portion of the screw and is damaged with low stress. is there. On the other hand, in order to improve these disadvantages, Patent Document 3 provides a screw hole on the side surface of the tool body, and presses and fixes the side surface of the rear end of the blade portion inserted into the tool body with a bolt passed through the screw hole. The configuration is disclosed. However, the configuration in which the side surface of the rear end of the blade portion inserted into the tool body is pressed and fixed with a bolt has the advantage that the blade portion can be easily replaced, but the center axis of the blade portion and the tool body is made to coincide. It is difficult to process with high accuracy. Moreover, since the restraint surface which supports the cutting torque concerning a blade part is small and is formed in the vicinity of a tool axis line, the force which grasps a blade part is small, and there exists a fault which cannot be used for heavy cutting. Patent document 4 is disclosing the structure which fixes a blade part using the elastic deformation of a holder. However, in the structure in which the blade portion is fixed by utilizing the elastic deformation of the tool body, it is possible to match the central axes of the blade portion and the tool body while maintaining good workability. Since the blade is fixed only by the deformation action, excessive force is repeatedly applied to a specific part of the tool body as the blade is repeatedly replaced. As a result, the elastic force of the holder is weakened, and the blade is There is a problem of falling off or damaging the main body. Patent document 5 is disclosing the structure which draws in a blade part in a tool main body using a hook type | mold means. However, in the configuration in which the blade part is pulled into the tool body using the hook type means, the force in which the hook part pulls the blade part toward the tool body side is not parallel to the tool axis, and the direction in which eccentricity occurs between the blade part and the tool body. Will act on. Moreover, since the hook portion provided in the blade portion is formed in a tapered portion for the purpose of coaxial mounting of the blade portion and the tool body, the outer peripheral surface of the blade portion is the inner periphery of the taper hole of the mounting hole. The force that presses the surface is also greatly biased, and the eccentricity of the blade portion becomes more prominent. For this reason, there exists a fault which cannot perform highly accurate processing. In addition, the constraining surface that supports the cutting torque applied to the blade part and the force that pulls the blade part into the tool body is a single hook part, and since the area is small, the stress concentration is large and the fragile hook part is deformed or damaged. is there.
Accordingly, the problem to be solved by the present invention is to provide a blade-exchangeable cutting tool in which the blade portion can be easily replaced and the blade portion can be attached with high strength and high accuracy.

The present invention relates to a blade part replaceable cutting tool comprising a blade part (1) and a tool body (2) that are detachably fixed, and a connecting part that extends rearward in the tool rotation axis direction of the blade part (1). (3) A detachable blade fixing member (4) is attached, and is attached to the tool body (2) via the blade fixing member (4). The blade fixing member (4) an opening portion provided in the side surface of the tool axis the blade portion fixing member along the (4) (18) have, the connection portion the blade unit fixing member to the side of (3) (4) of the opening (18) fitted by pushing the tool axis direction perpendicular to become the mounting direction (12) from the tool axis of the state the blade portion fixing member (4) is fitted to said connecting portion (3) In the cross section at right angles, the connecting portion (3) and the blade portion fixing member (4) have a flat region (10, 10) parallel to the mounting direction (12) and the mounting direction (12 And a flat region (11) perpendicular to each other, and a plurality of surfaces that are substantially U-shaped, and the opening (18) of the blade fixing member (4) is a circular shape of the connecting portion (3). The connecting portion (3) is fitted so as to correspond to the surface, and the connecting portion (3) has a cylindrical portion (9) having a diameter larger than that of the connecting portion (3) on the rear side in the tool rotation axis direction. The external thread (13) on the outer periphery of the part fixing member (4) and the internal thread (14) provided in the attachment hole (5) of the tool body (2) are screwed together to form the blade (1). Is mounted on the tool body (2). By adopting the above configuration, the blade part can be easily replaced, and a blade part exchange-type cutting tool that can attach the blade part with high strength and high accuracy can be realized.

In the blade part replaceable cutting tool of the present invention, the flat region (10 or 11) is preferably provided on a substantially flat surface. It is preferable that the contact surface (6) of this blade part (1) and this tool main body (2) is a taper shape. At least one part of the blade part (1) is a high hardness material such as cemented carbide, cermet, ceramics, CBN, etc., and the blade part fixing member (4) is, for example, a high-speed tool steel or other steel material. It is preferable to use a high-strength material such as The blade portion (1) has a through hole (7), the tool body (2) has a through hole (8), and the through hole (7) and the through hole (8) are connected to each other. It is preferable because the cutting oil or compressed air can be directly provided in the vicinity of the cutting edge.

  According to the present invention, it is possible to realize a blade-exchangeable cutting tool in which the blade portion can be easily replaced and the blade portion can be attached with high strength and high accuracy.

The blade part replaceable cutting tool of the present invention is provided with a connection part ( 3 ) in one part of the blade part (1), and a blade part fixing member (4 ) detachably attached to the outer peripheral part of the connection part ( 3 ). ), The blade portion is separated into the blade portion main body and the fixing member, and the connecting portion (3) of the blade portion (1). After attaching the detachable blade fixing member (4) substantially symmetrically, the blade (1) is fixed to the tool body (2) via the blade fixing member (4). The replacement of (1) is easy, and the blade (1) can be attached to the tool body (2) with high strength and high accuracy.
FIG. 1 shows a cross-sectional view as an example of the blade part exchange-type cutting tool of the present invention.
From FIG. 1, after attaching the blade fixing member (4) to the connecting portion (3) by fitting in order to fix the blade portion (1) having one or more cutting blades to the tool body (2). These are structures that are pushed into the tool body (2) and fixed by screwing. Therefore, it is possible to select optimum materials for the blade portion, the blade portion fixing member (4), and the tool body (2). On the contrary, if the blade part (1) and the blade fixing member (4) are integrally formed, the strength of the blade part fixing part is increased by giving priority to the high hardness of the blade part (1). There is a drawback that the fixing strength of the blade portion is reduced at the expense.
The blade part replaceable cutting tool of the present invention forms a male screw on the outer periphery of the blade part fixing member (4), is screwed with a female screw (14) applied to the mounting hole (5), and is connected to the connecting part (3 ) And the blade portion fixing member (4) are both screwed into the mounting hole (5), which makes it easy to replace the blade portion on the machine tool and is excellent in work efficiency.

By providing a cylindrical portion (9) having a diameter larger than that of the connection portion (3) behind the connection portion ( 3 ) in the tool rotation axis direction , the blade portion fixing member ( 4 ) is moved rearward in the tool rotation axis direction . It works so as not to move, and it is preferable because the blade fixing member ( 4 ) can be physically prevented from moving rearward in the tool rotation axis direction unnecessarily.
Further, since the contact surface of the blade portion (1) and the tool body (2) (6) is tapered, the blade portion (1) a higher strength, and preferable because mounted with high precision . Moreover, by two-face restraint of the blade section (1) and tool body (2) an end face (17) and the abutment surface of the tapered (6), high strength, and, mounting a high-precision cutting portion This is preferable.
At least one part of the blade part ( 1 ) is a high-hardness material such as cemented carbide, cermet, ceramics, CBN, etc., and the blade part fixing member ( 4 ) is made of a steel material such as high-speed tool steel, for example. A high strength material is preferred. In particular, in the present invention, when the blade portion ( 1 ) and the tool body ( 2 ) are made of high-hardness materials such as cemented carbide, cermet, ceramics, CBN, etc., both of them are members for fixing the blade portion of a high-strength material. By attaching by ( 4 ) , a high-hardness blade part and a tool main body can be attached with high strength via a high-strength blade part fixing member, which is a more preferable form.
Blade portion (1) to form a through-hole (7), by connecting the through-hole of the tool body (2) (8), can be fed directly to cutting oil or compressed air in the vicinity of the cutting edge. Thereby, it is excellent in chip removal property and blade portion cooling property, and it is possible to cut a high-hardness material more efficiently, which is preferable.

In the blade part exchangeable cutting tool of the present invention, a supplementary material may be set to the opening (18) of the blade part fixing member ( 4 ) so as to complement the circular surface (19) in an axial symmetry. As the axial symmetry is increased, the dynamic balance is excellent, and higher precision machining is possible, which is preferable.
The invention of the present application can be applied to various blade part exchangeable cutting tools such as a drill and a reamer by changing the cutting edge shape of the blade part ( 1 ) . Further, by forming the blade portion (1) by injection molding, it is possible to diameter of the blade portion (1). Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

One example of the blade part replaceable end mill of the present invention and Example 1 of the present invention are shown in FIGS.
From FIG. 2, the blade part (1) of the present invention example 1 has a square end mill shape with a tool diameter of 6 mm. The material of the blade part (1) was made of a WC—Co cemented carbide, and was coated with a (TiSi) N film using an arc ion plating method. The tool body (2) was also made from a WC-Co cemented carbide material. In this embodiment, a WC-Co cemented carbide material is selected for the tool body (2), but an SKD61 material of HRC45 can also be selected.
From FIG. 3, the blade (1) is provided with a contact surface (6) for the purpose of coaxial mounting to the tool body (2) at the rear of the tool rotation axis, and the contact surface (6) is 5 °. Has a tapered shape. Furthermore, the cylindrical part (9) was provided in the tool rotation axis direction back of the connection part (3). The blade fixing member (4) is fitted from the mounting direction (12), and the connected connecting portion (3) is inserted into the mounting hole (5) of the tool body (2) from the mounting direction (20). The external thread (13) on the outer periphery of the blade fixing member (4) and the internal thread (14) of the tool body (2) are screwed together to fix the blade part (1) to the tool body (2). did. The pushing force of the blade (1) includes a male screw (13) formed on the outer periphery of the blade fixing member (4) and a female screw (14) formed in the mounting hole (5) of the tool body (2). It was possible to easily attach and detach using the wrench hook (15) formed on the blade portion (1) by utilizing the axial force generated by the screwing.
As shown in FIG. 4, the blade fixing member (4) is made of an HRC45 SKD61 material, and the connecting portion (3) fitted to the blade fixing member (4) has an axial length of 8 mm. The cylindrical portion (9) is made larger in diameter than the connecting portion (3) and the contact surface (16) is provided behind the blade portion fixing member (4) in the tool rotation axis direction. 6), the relative movement of the blade portion (1) and the blade portion fixing member (4) in the tool rotation axis direction rearward is restricted.
As shown in the cross section perpendicular to the axis in FIG. 5, the connecting portion (3) and the blade portion fixing member (4) have two flat regions (10) in a straight line shape parallel to the mounting direction (12) and flat. The region (11) has a positional relationship of 90 ° around the axis with the flat region (10), the circular surface (19) is left as it is, and the blade fixing member (4) has the circular surface. An opening (18) corresponding to (19) was provided. By providing these surfaces, it is possible to limit the mounting of the connection portion 3 (and) the blade portion fixing member (4) only in the mounting direction (12), thereby improving the repeated mounting accuracy.
Furthermore, the flat region (10), (11), the substantially by a U-shaped connecting portion (3) and the blade portion fixing member (4) and the easily removable (10), the flat It is possible to firmly restrain the three surfaces (10, 10) and (11).
Further, Invention Examples 2 to 6 having a structure according to Invention Example 1 except that the tool diameter was different were produced. For Conventional Examples 7 to 10, hook-type blade part replaceable tools were prepared.
The evaluation items of Invention Examples 1 to 6 and Conventional Examples 7 to 10 were the runout accuracy of the blade portion, the mounting accuracy and the mounting strength when this was repeated. As the evaluation method, a laser tool diameter measuring instrument was used to measure the deflection accuracy of the blade portion. Moreover, the precision at the time of attaching this repeatedly 10 times was evaluated. The attachment strength of the blade was evaluated by tightening to a predetermined torque using a torque wrench. The evaluation criteria were to observe the joints at each tightening torque and evaluate the presence or absence of damage or breakage. The evaluation results are shown in Table 1.

From Table 1, Examples 1 to 6 of the present invention have a deflection accuracy of the blade portion of 10 μm or less and can be attached with high accuracy. In particular, the center axis is matched by the fitting of the connecting part (3) and the blade fixing member (4), the screw fixing of the blade fixing member (4) and the tool body (2), and the contact surface. It was effective to form ( 16 ) in the same plane perpendicular to the axis and to make the force that the blade (1) pushes in parallel with the axis. Moreover, the blade part with excellent operability could be replaced. However, in the conventional example, as compared with the example of the present invention, the deflection accuracy of the blade portion is a large value of about four times, which is inferior in accuracy.
The repeat mounting accuracy of the example of the present invention was 8 μm or less, and it was possible to mount with high accuracy. The blade part ( 1 ) and the tool body ( 2 ) can be mounted on the edge part ( 17 ) and the tapered contact surface ( 6 ) so that the blade part can be mounted with high accuracy. However, when compared with the example of the present invention, the conventional example showed a value about three times larger, and the accuracy was inferior.
The tightening of the example of the present invention includes the fitting of the connecting portion (3) and the blade fixing member (4), the screwing of the blade fixing member (4) and the tool body (2), and the contact surface (6), The contact surface (16) was not damaged. However, in the conventional example, the hook portion was damaged. Therefore, the present invention example was able to be tightened more strongly than the conventional example. This indicates that the vibration of the cutting edge can be reduced in high feed machining or deep cutting, so that the tool life is long and the work surface of the workpiece is in a good state.

FIG. 1 shows a cross-sectional view of an example of a blade-exchangeable cutting tool according to the present invention. FIG. 2 shows a perspective view of an example of the present invention. FIG. 3 shows a perspective view of FIG. FIG. 4 shows a cross-sectional view of FIG. Figure 5 shows an axial sectional view perpendicular to the line A-A of FIG.

1: Blade part 2: Tool body 3: Connection part 4: Blade part fixing member 5: Mounting hole 6: Contact surface 7: Through hole of blade part
8: a tool body of the through hole 9: cylindrical portion 10 of the connecting portion (3): flat region 11: the flat region 12: a mounting direction of the connection portion of the blade fixing member 13: male thread 14: female screw 15: Wrench Hanging 16: Contact surface 17: End surface 18: Opening
19: Circular surface
20: Direction of attachment of the blade to the tool body

Claims (5)

In the blade part replaceable cutting tool formed by detachably fixing the blade part (1) and the tool body (2), the connecting part (3) extending rearward in the tool rotation axis direction of the blade part (1) is provided. The detachable blade fixing member (4) is attached, and is attached to the tool body (2) via the blade fixing member (4). The blade fixing member (4) has an opening provided in the side surface of the blade portion fixing member along the direction (4) (18), the opening of the blade portion fixing member to the side of the connecting portion (3) (4) In the tool axis perpendicular section in a state where the blade fixing member (4) is fitted to the connecting portion (3) by being pushed and fitted in the mounting direction (12) which is the tool axis perpendicular direction from (18) . The connecting portion (3) and the blade portion fixing member (4) include a flat region (10, 10) parallel to the mounting direction (12) and a flat region perpendicular to the mounting direction (12). A plurality of surfaces having a substantially U-shape with the region (11), and the opening (18) of the blade portion fixing member (4) is a circular surface (19) of the connection portion (3) The connecting portion (3) has a cylindrical portion (9) having a diameter larger than that of the connecting portion (3) at the rear of the connecting portion (3) in the tool rotation axis direction, and the blade portion fixing member The male screw (13) on the outer periphery of (4) and the female screw (14) provided in the mounting hole (5) of the tool body (2) are screwed together, and the blade (1) is attached to the tool body. (2) The blade part exchange-type cutting tool characterized by being mounted in (2). The blade part replaceable cutting tool according to claim 1, wherein the flat region (10 or 11) is provided on a substantially flat surface.   The blade part replaceable cutting tool according to claim 1 or 2, wherein the contact surface (6) between the blade part (1) and the tool body (2) is tapered. Cutting tools.   The blade part replaceable cutting tool according to any one of claims 1 to 3, wherein at least one part of the blade part (1) is a high hardness material and the blade part fixing member (4) is a high strength material. The blade part replaceable cutting tool.   The blade part replaceable cutting tool according to any one of claims 1 to 4, wherein the blade part (1) has a through hole (7), the tool body (2) has a through hole (8), The blade part exchangeable cutting tool, wherein the through hole (7) and the through hole (8) are connected.

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