JP4136977B2 - Cutting tools and machine tools - Google Patents

Description

  The present invention relates to a cutting tool that can be used for turning and the like, and a machine tool including the cutting tool.

  As shown in FIGS. 1 (a) and 1 (b), a cutting tool used for turning or the like includes a cutting blade portion (chip) 2 that actually interferes with a work material and a bite body 1 that supports the cutting tool portion. Prepare. In the turning process, a part of the work material is removed and processed into a desired shape by the relative movement of the linear feed movement of the cutting tool and the rotational movement of the work material.

  The cutting tool main body 1 includes a cutting tool head 1a that directly supports the cutting edge portion 2, and a cutting tool handle 1b that is fixed to a base 3 of the machine tool. The bite handle portion 1b and the bite head portion 1a are usually integrated.

  Generally, the cutting edge portion 2 is made of a cemented carbide and the cutting tool body 1 is made of a highly rigid material such as steel. However, when the cutting length of the cutting tool body 1 from the pedestal 3 of the machine tool is large, In intermittent cutting in which cutting state and non-cutting state appear alternately, such as turning, processing of a black skin portion in which the cutting thickness varies easily, and processing of cast iron or the like, vibration during processing tends to increase. Therefore, it tends to lead to deterioration of the finished surface and damage to the cutting edge.

  As a method for solving such a problem, a specific frequency can be obtained by combining a method for increasing the rigidity of the bite body 1, a method for increasing the damping of vibration of the bite body 1, and members having different natural frequencies. For example, a method of suppressing the resonance state with the above can be considered. Among these, the method of improving the rigidity of the bite body 1 is not desirable from the viewpoint of impact force during intermittent cutting because the burden on the tool edge increases. On the other hand, the method of improving the damping property also has the effect of reducing the impact force at the time of machining, and it can be expected not only to suppress the vibration but also to suppress the damage of the tool including the impact relaxation. it can.

  In order to improve the attenuation function of the bite body 1, two methods of using a highly attenuated material as the material of the bite body 1 and improving the attenuation by the structure of the bite body 1 can be considered.

  As an example of the former, a damping tool described in JP-A-2003-62703 can be cited. In this document, there is provided a vibration damping tool in which a tool body is provided with a hole that is positioned below the throw-away tip and is open on at least one side surface, and a vibration damping material that absorbs vibration energy generated in the tool body is mounted in the hole. Are listed.

  On the other hand, as an attempt to improve the damping property by devising the structure, a boring bar described in JP-A-6-31505 and a cutting tool described in JP-A-5-228707 can be exemplified.

  In the boring bar described in Japanese Patent Laid-Open No. 6-31505, the insertion hole provided in the shank is provided with a damper made of a material different from the material constituting the shank and in close contact with the tapered portion of the insertion hole. Then, a frictional vibration absorbing action is generated between the damper and the shank so as to attenuate the vibration generated in the cutting edge during cutting.

In the cutting tool described in Japanese Patent Application Laid-Open No. 5-228707, a pair of friction damping materials are arranged on the mutually opposing surfaces of the cutting head and the tool body so that they can contact each other, and these friction damping materials slide. Thus, the vibration energy is converted into frictional heat and the vibration propagated to the tool body is reduced.
JP 2003-62703 A JP-A-6-31505 JP-A-5-228707

  As the high damping material, a damping alloy having a high damping property such as a Mn-Cu based damping alloy is used. However, such an alloy often has a problem of being expensive or difficult to process, and the material system is changed. If the damping property is increased, the strength and rigidity are often decreased. Therefore, it is difficult to obtain what satisfies the required characteristics in both performance and cost. Further, when a soft material such as rubber is used as the high damping material, there are many practical problems because the rigidity and durability of the tool are significantly reduced. Furthermore, it is conceivable that only a part of the cutting tool is made of a high damping material. However, since actual vibration mainly propagates through the cutting tool main body, it is difficult to increase the damping performance of the entire tool. On the other hand, if the entire tool is made of a high-attenuating material, the rigidity and strength of the tool are lowered as described above, resulting in an increase in deflection and a decrease in durability.

  On the other hand, it is desirable to generate a frictional force in a large area in a method using friction between the bite body and another part or between different parts. However, if the frictional force is simply generated in a large area, it is necessary to process many parts of the cutting tool, which may increase the cost. In addition, if the adhesion between the separate parts and the holder is poor, the rigidity will be reduced, and there is a risk that vibration will increase.

  Also, as shown in FIGS. 2A to 2C, in the case of outer diameter machining in which, for example, a square bite is often used, the feed component force direction (the bite feed direction) rather than the main component force direction where the greatest force is applied. ) In many cases, the vibration acceleration of the tool becomes large. Further, in the turning process, there is an end face process shown in FIGS. 7B and 7C in addition to the outer diameter process. In this case, vibration tends to increase in the direction of the back component force. That is, the bending vibration in the direction along the bottom surface of the tool tends to be larger than the bending vibration in the direction perpendicular to the bottom surface of the tool. It is considered that the bending vibration in the direction along the bottom of the cutting tool affects the contact state between the flank and the work material from the tool edge. Since damage in this region can be a factor in shortening the tool life, it is important to effectively suppress vibration in the same direction in order to suppress damage to the tool.

  However, the invention described in each of the above prior art documents does not describe a specific method for positively suppressing vibration in the feed component force direction (tool feed direction) or the back component force direction. Therefore, damage to the tool in the region from the tool blade edge to the flank cannot be effectively suppressed, and this may cause a problem that the tool life cannot be improved.

  The present invention has been made to solve the above-described problems, and has a high damping performance particularly in bending vibration in the plane along the bottom surface of the cutting tool while minimizing a decrease in rigidity and an increase in cost. As a result, it is an object of the present invention to provide a cutting tool capable of effectively suppressing vibration during machining, suppressing damage to the cutting blade, and extending the service life, and a machine tool including the cutting tool.

In one aspect, the cutting tool according to the present invention has a cutting edge portion, a head on which the cutting edge portion is mounted, and a handle that continuously extends from the head and is fixed to a base of a machine tool. A main body. And, it extends along the bottom of the tool body that contacts the pedestal of the machine tool, and has slits that penetrate the handle so as to open on both sides of the tool body, so that the entire member can move relative to the handle In this way , a plate-like member is fitted into the slit, and the upper and lower surfaces of the plate-like member are brought into contact with the handle portion to generate a frictional force in the width direction of the handle portion along the contact surface between the plate-like member and the handle portion. Let

  By providing a slit as described above, inserting a plate-like member in the slit and bringing the upper and lower surfaces of the plate-like member into contact with the handle, it is possible to reduce the strength and rigidity of the bite body portion while cutting. A frictional force can be applied between the plate-like member and the handle portion of the bite body portion. As a result, a large frictional force can be applied in a direction parallel to the bottom surface of the tool body, and the vibration of the tool body in the feed force direction during outer diameter machining (the back force force direction during end face machining) is effective. Can be suppressed. In addition, since a slit is provided so as to penetrate between both side surfaces of the tool body handle, and a plate-like member is provided in the slit, the compressive force applied to the tool when gripped by the machine tool is reduced during outer diameter processing. If so, the distribution is uniform in the feed direction (the direction perpendicular to the paper surface in FIG. 3). If the compressive force is uneven, the gripping state of the cutting tool becomes unstable, and as a result, there is a possibility of adversely affecting the vibration state of the cutting tool. However, such a bad influence can be avoided in the cutting tool according to the present invention.

In another aspect, the cutting tool according to the present invention is provided with a slit penetrating the handle so as to extend along a plane defined by the feed component force direction and the back component force direction at the time of cutting. The plate member is inserted into the slit so that the entire member can be moved relative to each other, and the upper and lower surfaces of the plate member are brought into contact with the handle portion, so that the handle portion along the contact surface between the plate member and the handle portion is Generate frictional force in the width direction. Even when the slit that penetrates the handle portion is provided so as to extend along the plane defined by the feed component force direction and the back component force direction, the outer diameter is the same as in the case of the above one aspect. A large frictional force can be applied in the feed component force direction during machining (the back component force direction during end face machining). Also, when the surface defined by the feed component force direction and the back component force direction is not parallel to the bottom surface of the bite body (including the case where the bite bottom surface is a curved surface), the feed component force direction or the back component force A large frictional force can be applied in the direction.

  When the cutting tool is installed in a machine tool, a slit and a plate-like member are provided so as to reach a cross section perpendicular to the longitudinal direction of the cutting tool at the end portion on the cutting edge portion side of the portion contacting the pedestal of the machine tool Is preferred.

It is preferable that the slit is provided so as to reach the end surface on the opposite side of the head portion in the longitudinal direction of the handle portion, and the plate member is inserted over the entire slit. Further, the thickness of the slit and the plate-like member is preferably not less than a large value of 5% and 1 mm of the thickness of the handle and not more than a large value of 20% and 3 mm of the thickness of the handle. The “thickness of the slit and the plate-like member” means the direction from the mounting surface of the cutting edge portion in the head of the cutting tool main body to the bottom of the cutting tool main body (for example, the vertical direction in FIG. 3: the fixing surface 8 of the base 3 The thickness in the direction perpendicular to). Moreover, it is preferable to comprise a plate-shaped member with a cemented carbide . Further, a counterbore may be provided on the side surface of the handle and a slit may be provided so as to open in the counterbore.

  A machine tool according to the present invention includes the above-described cutting tool and a base on which the cutting tool is fixed. Then, the cutting tool is fixed to the pedestal so that a part on the cutting edge side of the cutting tool main body portion of the cutting tool protrudes from the machine tool pedestal. The aforementioned slits and plate-like members are provided so as to reach.

  As a result, the portion of the plate-like member located on the machine tool pedestal is more firmly fixed from the bite body than the portion located in the protruding portion, and as a result, the portion located in the protruding portion moves relative to the bite body. And the vibration of the bite body can be effectively suppressed by the friction force generated at that time.

  According to the present invention, the slit is provided in the direction along the bottom surface (the plane defined by the feed component force direction and the back component force direction) of the bite body portion, and the plate-like member is fitted into the slit. A large frictional force can be applied in the feed component force direction during outer diameter machining (back component force direction during end face machining) while suppressing the strength and rigidity reduction of the bite body portion. Vibration can be effectively suppressed. Therefore, while minimizing the decrease in rigidity and cost, the damping performance is high especially in the bending vibration along the bottom of the cutting tool. As a result, the vibration during machining is effectively suppressed and the damage to the cutting edge is suppressed. Thus, it is possible to provide a cutting tool capable of extending the life and a machine tool including the cutting tool.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

(Embodiment 1)
FIG. 3 is a side view showing the cutting tool (bite) and a part of the machine tool according to Embodiment 1 of the present invention. As shown in FIG. 3, the cutting tool according to the first embodiment includes a cutting edge portion (tip) 2, a head 1a to which the cutting blade portion 2 is attached, and a work extending continuously from the head 1a. A tool body 1 having a handle 1b fixed to a base 3 of the machine.

  The cutting blade portion 2 is made of, for example, cemented carbide, and is fixed to the head 1a of the bite body 1 by a clamping mechanism or a brazing method. The bite body 1 is made of, for example, Cr—Mo steel. A slit 4 is provided in the handle portion 1 b of the bite body portion 1.

  As shown in FIG. 4A, the slit 4 is provided so as to penetrate the handle portion 1 b of the bite body portion 1. The slit 4 extends along the bottom surface of the cutting tool main body 1 located on the side opposite to the surface on which the cutting blade portion 2 is mounted (the upper surface of the cutting tool main body 1), and opens on both side surfaces of the handle 1b. To do. The slit 4 penetrates the handle portion 1b of the cutting tool main body 1 so as to extend along a plane defined by the feed component force direction and the back component force direction during cutting.

  The plate-like member 5 is fitted into the slit 4, and the upper and lower surfaces of the plate-like member 5 are brought into contact with the handle 1b as shown in FIG. The plate-like member 5 only needs to have sufficient rigidity when the tool is fixed to the machine tool, and the plate-like member 5 can be made of a metal material that is not extremely soft in addition to steel. It is. By fitting such a plate-like member 5 into the slit 4 and bringing its upper and lower surfaces into contact with the handle 1b, a desired frictional force is generated between the plate-like member 5 and the bite body 1 during cutting. Can be made.

  Further, by adopting the plate-like member 5 having a large area on the upper and lower surfaces, the contact area between the plate-like member 5 and the bite body 1 can be increased, and the plate-like member 5 and the bite body 1 at the time of cutting. A large frictional force can be generated between the two. Therefore, the vibration of the cutting tool main body 1 during processing can be effectively damped.

  When the plate-like member 5 is arranged in a direction parallel to the bottom surface of the bite body 1 as in the example of FIG. 3, in the feed component force direction during outer diameter processing (the back component force direction during end surface processing). Since a large frictional force can be applied, vibration of the cutting tool main body 1 in the same direction can be effectively suppressed. Thereby, damage to the cutting edge portion 2 can be suppressed.

  In order to generate a larger frictional force between the plate-like member 5 and the bite body 1 at the time of cutting, it is preferable that the plate-like member 5 and the bite body 1 are brought into close contact with each other. For example, a large frictional force is generated by fitting the plate-like member 5 into the slit 4 by a method such as press fitting or shrink fitting, and inserting the plate-like member 5 into the slit 4 in an interference fit or intermediate fit state. Can be made. Further, by using a fastening force (a force applied to the upper surface of the tool body 1 and acting in the vertical direction in FIG. 3) when fixing the tool body 1 to the pedestal 3 of the machine tool. In addition, the plate-like member 5 and the bite body 1 can be more closely attached.

  By providing the slit body 4 with the slit 4 as described above, it is considered that the rigidity of the tool body portion 1 is slightly lowered. Therefore, a device for reducing the degree of rigidity reduction of the tool body 1 is required. On the other hand, if the plate-like member 5 is too thin, a desired frictional force may not be obtained. Therefore, the relationship between the thickness t2 of the slit 4 and the plate-like member 5 shown in FIG. 3 and the thickness t1 of the handle 1b of the bite body 1 will be described.

  If the thickness t2 of the slit 4 and the plate-like member 5 is too large, the rigidity of the bite body 1 may be significantly reduced. Therefore, the thickness t2 is set to about 20% or less of the thickness t1 of the handle 1b of the bite body 1. As a result, a decrease in rigidity of the tool body 1 can be suppressed to a small level, and a decrease in vibration resistance of the tool body 1 caused by the decrease in rigidity can be suppressed. Further, the influence on the dimensional accuracy of the processed product can be reduced.

  On the other hand, if the thickness t2 of the slit 4 and the plate-like member 5 is too small, the rigidity of the plate-like member 5 itself is reduced, and the frictional force acting between the plate-like member 5 and the bite body 1 is reduced. . Therefore, it is preferable that the thickness t2 of the slit 4 and the plate-like member 5 is about 5% or more of the thickness t1 of the handle 1b of the bite body 1.

  However, for example, when the thickness t1 of the handle 1b of the bite body 1 is a small bite of around 10 mm, the object to be processed is limited to a low load, so the thickness t2 is set to be larger than 20% of the thickness t1. However, the effect of lowering the rigidity is reduced. Specifically, even when the thickness t2 of the slit 4 and the plate-like member 5 is about 3 mm, the influence of the rigidity reduction of the bite body 1 is reduced.

  In the case of the small tool as described above, if the thickness t2 is about 5% of the thickness t1, the plate-like member 5 becomes too thin and the plate-like member 5 is likely to be warped. 5 becomes difficult. Therefore, the thickness t2 of the slit 4 and the plate-like member 5 is preferably about 1 mm or more.

  In view of the above, the thickness t2 of the slit 4 and the plate-like member 5 is greater than the larger value of 5% and 1 mm of the thickness t1 of the handle 1b of the cutting tool body 1, and 20% and 3 mm of the thickness t1 of the handle 1b. Of these, it is preferable to set it to a large value or less.

  When the plate-like member 5 is provided so as to protrude from the pedestal 3 of the machine tool as in Embodiments 2 and 3 to be described later, the plate-like member 5 is in a cantilever state. In particular, in the bending vibration in the plane along the bottom of the tool, the natural frequency of the plate-like member 5 tends to be higher than the natural frequency of the tool main body 1. Therefore, in this case, it becomes easier to obtain the friction damping effect of the bite body 1.

  The plate-like member 5 is preferably made of a material having a Young's modulus higher than that of the bite body 1. As a result, the natural frequency of the plate-like member 5 can be made higher than the natural frequency of the bite body 1, and the difference in vibration state between the plate-like member 5 and the bite body 1 becomes large, and a friction damping effect is obtained. It becomes easy to be done.

  In addition, by configuring the plate-like member 5 with a material having a higher Young's modulus than the bit body 1, it is possible to suppress a decrease in rigidity as the entire bit.

  4 (b) and 4 (c) show modified examples of the cross-sectional shape of the handle portion 1b of the bite body portion 1. FIG. As shown in FIG. 4B, counterbore 6 may be provided on both side surfaces of the handle portion 1 b, and the slit 4 may be provided so as to open in the counterbore 6. By providing the counterbore 6 in this way, the depth of the slit becomes small, so that the processing becomes easy. In this case, the contact area between the plate-like member and the bite body handle is reduced, but the magnitude of the compressive force acting on the plate-like member when the bite body handle is held by the machine tool is shown in FIG. The same effect as in the case of FIG. 4A can be expected with respect to the attenuation due to the frictional force acting between the tool body and the plate-like member.

  Moreover, as shown in FIG.4 (c), you may install the sealing component 7 in the spot facing 6 via an adhesive agent, resin, etc. As shown in FIG. Since the seal part 7 is a separate part from the tool body 1 and is fixed to the handle 1b via a soft material such as resin, the tool part to the machine tool is the same as in FIG. 4B. A sufficient compressive force can be applied to the plate-like member 5 at the time of fixing.

(Embodiment 2)
Next, Embodiment 2 of the present invention will be described with reference to FIGS. 5 (a) and 5 (b). FIG. 5A is a side view showing a cutting tool and a part of the machine tool in the second embodiment, and FIG. 5B is a cross-sectional view taken along the line Vb-Vb in FIG. It is.

  As shown in FIG. 5 (a), in the second embodiment, the handle 1b of the cutting tool body 1 reaches the protruding portion protruding from the pedestal 3 from the portion located on the pedestal 3 of the machine tool. A slit 4 and a plate-like member 5 are provided. Other configurations are the same as those in the first embodiment.

  By disposing the slit 4 and the plate-like member 5 as described above, the portion of the plate-like member 5 that is located on the base 3 and is fixed to the machine tool together with the handle 1b is firmly fixed. The plate-like member 5 and the handle 1b have a portion protruding from the base 3. Therefore, both the plate-like member 5 and the bite body 1 are in a state similar to a cantilever.

  The cutting force applied to the cutting edge portion 2 during the cutting process also acts on the plate-like member 5 via the bite body 1 and vibrates not only the bite but also the plate-like member 5. However, the cross-sectional shape of the plate-like member 5 and the protruding length from the pedestal 3 (the protruding length of the plate-like member 5 from the end of the pedestal 3 on the cutting blade portion 2 side) are also different from the bite body 1. . That is, two beams having different natural frequencies vibrate while in contact with each other. Since the movement states of the two are thus greatly different, relative movement occurs between the plate-like member 5 and the bite body 1 and it is easy to exhibit a damping effect due to friction.

  In addition, although the protrusion length from the base 3 of the pattern part 1b in the plate-shaped member 5 and the cutting tool main body 1 is not constant depending on the setting of the machine tool or the operator, the interference between the cutting tool and the work material or the machine tool. Therefore, for example, in the most general outer diameter turning process, the cutting blade side of the bite main body pattern portion is protruded by about 10 to 20% of the entire length of the bite handle portion in the longitudinal direction. Often used in the form. For this reason, for example, as shown in FIG. 5, by installing the plate-like member 5 from the vicinity of the head 1a of the bite body 1 to the center of the handle 1b or the vicinity thereof, the plate-like member 5 in most cases. Can be projected from the pedestal 3.

  Here, the structural example of the machine tool which can use the above-mentioned cutting tool is demonstrated.

  The machine tool includes a workpiece holding mechanism for holding a workpiece, a workpiece driving / moving mechanism for driving or moving the workpiece, a tool holding mechanism for holding a cutting tool, and driving or moving the tool holding mechanism to drive or move the cutting tool. And a tool driving / moving mechanism to be moved. As the work holding mechanism, for example, a work spindle having a chuck is employed, and as the tool holding mechanism, for example, a tool post for holding a tool is used. Then, the cutting tool main body 1 is fixed to the base of the tool rest as described above.

(Embodiment 3)
Next, Embodiment 3 of the present invention will be described with reference to FIGS. 6 (a) and 6 (b). FIG. 6A is a side view showing a cutting tool and a part of the machine tool in the third embodiment, and FIG. 6B is a cross-sectional view taken along line VIb-VIb in FIG. It is.

  In the third embodiment, the slit 4 is provided so as to reach the end face in the longitudinal direction of the handle 1 b of the bite body 1, and the plate-like member 5 is fitted over the entire slit 4. Other configurations are the same as those in the second embodiment.

  In the example shown in FIG. 6A, a slit 4 is provided over almost the entire length in the longitudinal direction of the handle portion 1b of the bite body portion 1, and the longitudinal end surface of the handle portion 1b (on the side opposite to the side on which the cutting blade portion 2 is attached). The slit 4 is open at the end face. And the plate-shaped member 5 is inserted over substantially the whole slit 4, and the end surface of the plate-shaped member 5 is exposed in the longitudinal direction end surface of said handle | pattern part 1b.

  By providing the slit 4 as described above, the handle 1b of the cutting tool body 1 is substantially divided in the vertical direction, and the upper portion and the lower portion of the handle 1b are connected via the head 1a. It will be.

  In each of the above-described embodiments, if the thickness of the plate-like member 5 is too thick relative to the thickness of the slit 4, the plate-like member 5 cannot be inserted into the handle 1b, and conversely the thickness of the plate-like member 5 is slit. If the thickness of the plate member 5 is too small, the upper and lower surfaces of the plate-like member 5 cannot be brought into contact with the handle portion 1 b, and a desired frictional force can be generated between the plate-like member 5 and the bite body portion 1. It becomes difficult. For this reason, high dimensional accuracy is required for the thickness of the plate-like member 5 and the slit 4.

  On the other hand, in Embodiment 3, the handle 1b of the cutting tool main body 1 is divided into a plurality of portions in the thickness direction (vertical direction) at the end of the cutting tool in the longitudinal direction. Even if slight variations occur in the thickness of the plate-like member 5, the plate-like member 5 can be easily sandwiched between the handle portions 1b. Therefore, high dimensional accuracy is not required for the thickness of the plate-like member 5 and the slit 4, which is advantageous in terms of processing cost.

  Further, since the handle 1b of the cutting tool body 1 is divided into a plurality of portions in the thickness direction (vertical direction) at the end of the cutting tool in the longitudinal direction, tightening when fixing the cutting tool to the base 3 of the machine tool is performed. The applied force can be efficiently applied to the plate-like member 5. That is, it becomes easy to apply a compressive force to the plate-like member 5 when fixing the cutting tool to the base 3 of the machine tool. In addition, since the plate-like member 5 can be extended over almost the entire handle 1b of the bite body 1, the contact area between the plate-like member 5 and the handle 1b can be increased. Thereby, a large frictional force can be generated between the cutting tool main body 1 and the plate-like member 5, and the vibration of the cutting tool main body 1 during processing can be further effectively damped.

  Next, examples of the present invention will be described. This inventor produced the conventional product and invention products 1-5 shown in the following Table 1, and performed each performance evaluation.

  The conventional cutting tool has the structure shown in FIG. 1, the cutting tool of invention 1 has the structure shown in FIG. 3, and the cutting tool of invention 2 has the structure shown in FIG. The cutting tools 3 to 5 have the structure shown in FIG.

  In the conventional product and the inventive products 1 to 5, the tool body 1 is made of quenched Cr-Mo steel. The length of the tool body 1 is 150 mm, the length of the handle 1b of the tool body 1 is 120 mm, and the width and thickness of the handle 1b are both 25 mm. The cutting edge portion (chip) 2 is made of a cemented carbide which is clamped on the head 1a of the bite body 1 and coated. Further, in the handle portion 1b, a portion between 40 mm and 150 mm (terminal) from the tip of the cutting edge is fixed to the base 3 of the machine tool.

  In the cutting tool of invention 1, a slit 4 having a thickness of 3 mm is provided at a position of 50 mm to 80 mm from the tip of the cutting edge with respect to the handle 1b of the cutting tool body 1 shown in FIG. A plate-like member 5 having a thickness equal to or greater than that and made of Cr-Mo steel is press-fitted. In the product 1 of the present invention, the plate member 5 is attached to the handle portion 1b so that the bottom surface of the plate member 5 is located at a height of 5 mm from the bottom surface of the handle portion 1b. The plate-like member 5 is substantially in contact with the handle 1b in the entire width direction (perpendicular to the paper surface) of the handle 1b.

  In the cutting tool of Invention 2, a slit 4 having a thickness of 3 mm is provided at a position 30 mm to 60 mm from the tip of the cutting edge with respect to the handle 1b of the cutting tool main body 1 shown in FIG. A plate-like member 5 having a thickness equal to or greater than that of the slit 4 and made of Cr-Mo steel is press-fitted. Therefore, in the cross section (Vb-Vb cross section in FIG. 5A) of the handle portion 1b located on the cutting blade side end of the base 3 of the machine tool in the direction perpendicular to the longitudinal direction of the cutting tool, FIG. ), The plate-like member 5 is disposed. The other configuration is the same as that of the invention 1.

  In the cutting tool of invention 3, the slit 4 having a thickness of 6 mm extends from a position 30 mm from the tip of the cutting edge to the end of the handle 1 b (end of the cutting tool) with respect to the handle 1 b of the cutting tool body 1 shown in FIG. The plate-like member 5 having the same thickness as the slit 4 and made of Cr—Mo steel is inserted into the slit 4. Also in this case, the cross section (VIb-VIb cross section in FIG. 6A) of the handle portion 1b positioned on the cutting blade side end of the base 3 of the machine tool in the direction perpendicular to the longitudinal direction of the cutting tool is shown in FIG. As shown in (b), the plate-like member 5 is disposed. Moreover, since the slit 4 is provided and inserted in almost the entire handle 1b, the plate-like member 5 can be inserted into the slit 4 relatively easily by widening the slit 4 slightly at the end of the handle 1b. . Further, when the cutting tool body 1 is fixed to the machine tool, the vertical compressive force is sufficiently applied to the plate-like member 5. The other configuration is the same as that of the invention 1.

  In invention 4, the length of slit 4 and the material of plate-like member 5 are the same as in invention 3, but the thickness of slit 4 and plate-like member 5 is 3 mm. That is, in the inventive product 3, the thickness (6 mm) of the slit 4 and the plate-like member 5 is 24% of the thickness (25 mm) of the handle portion 1b, whereas in the inventive product 4, the slit 4 and the plate-like member are used. The thickness (3 mm) of the member 5 is 12% of the thickness (25 mm) of the handle 1b.

  The invention product 5 has the same structure as the invention product 4 including the thickness of the plate-like member 5, but the material of the plate-like member 5 is a cemented carbide. The Young's modulus of Cr-Mo steel constituting the bite body 1 is about 200 GPa, whereas the Young's modulus of cemented carbide is about 600 GPa. The Young's modulus of the main body 1 is higher.

  For the above-mentioned conventional products and invention products 1 to 5, as an evaluation test, vibration measurement during machining and evaluation of chip fracture resistance in intermittent cutting were performed. The results are also shown in Table 1 above.

  Vibration measurement was performed at a cutting speed of 200 m / min. , Feed: 0.3 mm / rev, cutting: 1.5 mm, and was carried out in a state in which a round bar of Cr—Mo steel was subjected to external diameter turning by a dry method. Specifically, an acceleration pickup was attached to the bottom surface of the head 1a of the bite body 1, and frequency analysis was performed on the time series data of the obtained acceleration amplitude.

  Since the natural frequency of the tool system in this example is 3 to 7 kHz, paying attention to the peak appearing near this frequency in the frequency analysis result, the power value at the peak in each invention product is the peak in the conventional product. The value normalized by the power value at is obtained. This power value is a numerical value related to the square of the acceleration amplitude, and the larger this value is, the more severely the head 1a of the bite body 1 vibrates. In addition, vibrations in two directions, ie, the main component force direction (up and down direction of each bite drawing) and the feed direction (feed component force direction: the direction perpendicular to the paper surface of each bite drawing) are evaluated.

  From the results in Table 1, it can be seen that the vibration acceleration of each invention product is suppressed as compared with the conventional product. In particular, it can be seen that the effect of suppressing vibration in the feed direction is high. Further, the invention 2 in which the plate-like member 5 is arranged closer to the cutting edge portion 2 than the invention 1 in which the plate-like member 5 is arranged in the central portion of the handle portion 1b of the bite body 1. It can be seen that the vibration suppression effect is higher. That is, the vibration suppression effect can be enhanced by projecting the plate-like member 5 from the pedestal 3 of the machine tool toward the cutting edge portion 2 side.

  About the thickness of the slit 4 and the plate-shaped member 5, it turns out that the vibration suppression effect is higher in the invention 4 having a thickness of 3 mm than in the invention 3 having a thickness of 6 mm. From this, it is considered that if the thickness of the slit 4 and the plate-like member 5 is excessively increased, the rigidity of the whole tool is lowered regardless of the material of the plate-like member 5, and the vibration suppressing effect is also lowered accordingly.

  The invention product 5 in which the plate-like member 5 is cemented carbide is further superior to the invention product 4 in which the plate-like member 5 is steel. Therefore, by inserting a material having a high Young's modulus as the plate-like member 5 into the bite body 1, the difference in the vibration state between the bite body 1 and the plate-like member 5 is enlarged, and it becomes easy to draw out friction damping. In addition, it can be seen that various effects such as the ability to suppress a reduction in the rigidity of the tool occur in a composite manner, and as a result, an excellent vibration suppressing effect can be obtained.

  Next, the evaluation results regarding the influence of the product of the present invention on the damage to the cutting edge portion (chip) 2 will be described. This result is also shown in Table 1 above.

  The test conditions were cutting speed: 200 m / min. , Feed: 0.25 mm / rev, incision: 2.0 mm wet processing, and intermittent cutting was performed on Cr-Mo steel provided with grooves in the axial direction.

  Since the breakage of the cutting edge portion (chip) 2 is assumed to occur probabilistically, the evaluation is performed based on the average value in 10 tests. Table 1 shows the number of intermittent cuttings until the conventional product and the invention product are defective.

  As shown in Table 1, it can be seen that the number of intermittent cuttings until each invention product is lost is greater than that of the conventional product, and the life of each invention product is longer than that of the conventional product. In particular, invention products 2 to 5 in which a plate-like member 5 is protruded from the pedestal 3 of the machine tool to the cutting blade portion 2 side, and further a plate-like member 5 having a thickness of 3 mm over almost the entire handle portion 1b of the bite body portion 1. It can be seen that the inventions 4 and 5 in which are arranged have a high life extension effect.

  In Example 1, the effect of the product of the present invention was verified by outer diameter turning, but Example 2 shows the evaluation result in end face turning. Inventions to be evaluated are the same as in Example 1.

  Here, an FCD450 round bar was used as the work material, and the vibration state when the end face of the round bar was processed from the outer diameter side toward the center was measured. The processing conditions are a cutting speed of 130 m / min, a feed of 0.15 mm / rev, a cutting depth of 0.5 mm, and dry processing. In the same manner as in Example 1, an acceleration pickup was attached to the bottom surface of the bite head for evaluation.

  In the end face machining, unlike the outer diameter machining in the first embodiment, the direction of bending vibration in the plane along the bite bottom face corresponds to the back component force direction. Therefore, the vibration evaluation was performed in two directions of the main component force direction and the back component force direction.

  Table 2 shows the results. As can be seen from this, it can be seen that the vibration in the product of the present invention is particularly suppressed in the direction of the back component force. The influence of the thickness and material of the insertion member has the same tendency as in Example 1, and the inventions 4 and 5 have a particularly high vibration suppressing effect.

  The above is the case where the cutting tool is sent from the outer diameter side toward the center even in the end face processing (infeed processing: FIG. 7B), but the pulling process is performed to send the cutting tool from the center direction to the outer diameter direction (FIG. 7C). The same effect is obtained in)). In cases where tool feed movement is applied obliquely to the workpiece rotation axis (such as copying), the outer diameter machining and end face machining are combined, so the product of the present invention has a feed component force. It has been confirmed that vibration is suppressed in both the direction and the back component force direction.

  Next, the influence on the cutting edge damage in the end face processing will be shown. The results are also shown in Table 2. The machining conditions were a cutting speed of 130 m / min, a feed of 0.15 mm / rev, a cutting depth of 0.5 mm, and wet machining, and FCD450 was used as a work material. In cast iron processing, vibration is likely to occur, and tool wear is likely to be accelerated by the accumulation of minute damage. Therefore, here, the time until the average flank wear width VB reaches 0.25 mm was defined as the tool life, and each tool was evaluated based on the tool life.

  As shown in Table 2, the tool life also shows the same tendency as the vibration suppression effect, and the invention product, in particular, the invention in which a plate-like member having a thickness of 3 mm is disposed over almost the entire bite body handle portion. It can be seen that products 4 and 5 have a high life extension effect.

  As described above, in the product of the present invention, the vibration suppressing function of the entire tool, particularly the vibration suppressing function for bending vibration in the plane along the tool bottom surface is enhanced, and the damage to the cutting edge portion (chip) is effectively suppressed. be able to.

  Although the embodiments and examples of the present invention have been described as described above, it is also planned from the beginning to appropriately combine the characteristic configurations of the above embodiments and examples.

  The present invention is not limited to the above-described embodiments and examples. The scope of the present invention is defined by the terms of the claims, and includes meanings equivalent to the terms of the claims and all modifications within the scope.

  The present invention is effectively applied to cutting tools and machine tools.

(A) is a side view which shows the conventional cutting tool and a part of machine tool, (b) is sectional drawing which follows the Ib-Ib line | wire in (a). (A) is a figure which shows the main component force direction and feed component force direction in outer-diameter turning, (b) and (c) are vibration of the main component force direction and feed component force direction in outer-diameter turning. It is a figure which shows an acceleration, respectively. It is a side view which shows the cutting tool and some machine tools in Embodiment 1 of this invention. (A) is sectional drawing which follows the IVa-IVa line | wire in FIG. 3, (b), (c) is sectional drawing which shows the other example of the cross-section of a cutting tool main-body part. (A) is a side view which shows the cutting tool and some machine tool in Embodiment 2 of this invention, (b) is sectional drawing which follows the Vb-Vb line | wire in (a). (A) is a side view which shows the cutting tool and some machine tools in Embodiment 3 of this invention, (b) is sectional drawing which follows the VIb-VIb line | wire in (a). (A)-(c) is a figure which shows the direction of the cutting force in an outer-diameter process, an end surface infeed process, and an end surface raising process, respectively.

Explanation of symbols

  1 Bite body part, 1a head part, 1b handle part, 2 cutting edge part, 3 base, 4 slit, 5 plate-like member, 6 spot facing, 7 seal part, 8 fixing surface.

Claims (8)

A cutting edge part,
A tool body having a head portion to which the cutting blade portion is mounted, and a handle portion extending continuously from the head portion and fixed to a pedestal of a machine tool,
Extending along the bottom surface of the cutting tool main body contacting the base of the machine tool, and providing a slit penetrating the handle so as to open on both side surfaces of the cutting tool main body;
A plate-like member is fitted in the slit so that the entire member can move relative to the handle, and the upper and lower surfaces of the plate-like member are brought into contact with the handle, and the plate-like member and the handle A cutting tool that generates a frictional force in the width direction of the handle along the contact surface. A cutting edge part,
A tool body having a head portion to which the cutting blade portion is mounted, and a handle portion extending continuously from the head portion and fixed to a pedestal of a machine tool,
Provide a slit that penetrates the handle so as to extend along a plane defined by the feed component force direction and the back component force direction during cutting,
A plate-like member is fitted in the slit so that the entire member can move relative to the handle, and the upper and lower surfaces of the plate-like member are brought into contact with the handle, and the plate-like member and the handle A cutting tool that generates a frictional force in the width direction of the handle along the contact surface.   When the cutting tool is installed in the machine tool, the slit and the plate shape so as to reach a cross section perpendicular to the longitudinal direction of the cutting tool at the end portion on the cutting blade portion side of the portion contacting the base of the machine tool The cutting tool according to claim 1 or 2, wherein a member is provided.   The cutting according to any one of claims 1 to 3, wherein the slit is provided so as to reach an end face on the opposite side of the head portion in the longitudinal direction of the handle portion, and the plate member is inserted over the entire slit. tool.   The thickness of the slit and the plate-like member is not less than a large value of 5% and 1 mm of the thickness of the handle portion, and not more than a large value of 20% and 3 mm of the thickness of the handle portion. The cutting tool according to any one of claims 1 to 4. The cutting tool according to any one of claims 1 to 5, wherein the plate-like member is made of a cemented carbide .   The cutting tool according to claim 1, wherein a counterbore is provided on a side surface of the handle portion, and the slit is provided so as to open in the counterbore. The cutting tool according to any one of claims 3 to 7,
A pedestal to which the cutting tool is fixed;
The cutting tool is fixed to the pedestal so that a part of the cutting edge side of the handle portion of the cutting tool protrudes from the pedestal,
The machine tool which provided the said slit and the said plate-shaped member so that it might reach the protrusion part from the said base from the part located on the said base in the said handle | pattern part.

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