Rotating body with dynamic balancing mechanism, method for dynamically balancing a rotating body, cutting tool with dynamic balancing mechanism, and method for dynamically balancing a cutting tool

Abstract

The present invention provides a rotating body with a dynamic balancing mechanism, a method for dynamically balancing a rotating body, a cutting tool with a dynamic balancing mechanism, and a method for dynamically balancing a cutting tool, all of which offer a simple structure, a low number of parts, ease of manufacturing, fewer shape limitations, easy miniaturization, and a wide range of adjustable balance. [Solution] The device comprises a main body 1 that can be rotated around a central axis O, a flow channel 2 provided in the main body 1 and extending in the circumferential direction, a dilatant fluid 3 filled in the flow channel 2, and a weight housed in the flow channel 2. The weight is movable within the liquid dilatant fluid 3 when the magnitude of the acceleration acting on the dilatant fluid 3 due to the rotation of the main body 1 is less than a predetermined value, and is held in place by the solidified dilatant fluid 3 when the magnitude of the acceleration exceeds the predetermined value.

Description

Technical Field

[0001] The present invention relates to a rotating body with a dynamic balance adjustment mechanism, a method for adjusting the dynamic balance of a rotating body, a cutting tool with a dynamic balance adjustment mechanism, and a method for adjusting the dynamic balance of a cutting tool.

Background Art

[0002] Conventionally, a rotating body provided with a balance adjustment mechanism has been known (for example, Patent Documents 1 and 2). The rotating balancer device of Patent Document 1 detects an imbalance generated during the rotation of a rotating body by a field balancer, calculates the amount of movement of a weight for each balancer unit from the detection result, and corrects the imbalance of the rotating body by moving the weight. Specifically, the balancer unit is composed of a cylinder filled with a liquid, a weight, a spring, a pipe, and a valve, and corrects the imbalance of the rotating body by moving the weight according to the magnitude relationship between the centrifugal force and the spring force.

[0003] Further, the automatic dynamic balance device of Patent Document 2 includes a casing that rotates integrally with a rotating body, a storage chamber formed radially in the casing with respect to the circumferential direction of rotation of the casing, an outer cone housed in the storage chamber having a buffer region, an inner cone holding chamber formed in the outer cone, an inner cone held in the inner cone holding chamber having a buffer region, and a cover of the casing.

[0004] In this automatic dynamic balancing device, the centrifugal force generated by the rotation of the rotating body causes the sliding surface formed on the outer circumference of the outer weight to be biased by a guide surface formed on the inner circumference of the storage chamber, and is guided to slide toward the bottom of the storage chamber, thereby changing the rotational position of the outer weight within the storage chamber. Simultaneously, the centrifugal force generated by the rotation of the rotating body causes the sliding surface formed on the outer circumference of the inner weight to be biased by a guide surface formed on the inner circumference of the inner weight holding chamber drilled in the outer weight, and is guided to slide toward the bottom of the inner weight holding chamber, thereby changing the rotational position of the inner weight within the inner weight holding chamber. As a result, even if the rotational conditions fluctuate, such as changes in the rotational speed or rotational weight of the rotating body in various machine tools, the device can automatically correct dynamic imbalances such as swing during rotation by following these fluctuations. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2006-272541 [Patent Document 2] Japanese Patent Publication No. 2009-41633 [Overview of the project] [Problems that the invention aims to solve]

[0006] Conventional balance adjustment mechanisms had room for improvement in several aspects, including their complex structure and large number of parts, resulting in complicated manufacturing processes, numerous limitations due to their shape, size limitations that made it difficult to miniaturize them due to the use of small parts, and a narrow range of balance adjustment.

[0007] Furthermore, cutting tools are known as examples of this type of rotating body. For example, a cutting tool with a cutting diameter of φ50 mm is rotated n=33000 min -1When rotated at this speed, the cutting speed can reach 5200 m / min (312 km / h), and the centrifugal force acting on the mounting seat of the cutting insert can reach 2500 N (approximately 250 kgf). In cutting tools used under such harsh conditions, even a slight eccentricity places a large load on the spindle of the machine tool, significantly impacting cutting accuracy and tool life. Therefore, the precision of rotational balance adjustment is considered even more important.

[0008] The present invention aims to provide a rotating body with a dynamic balancing mechanism, a method for dynamically balancing a rotating body, a cutting tool with a dynamic balancing mechanism, and a method for dynamically balancing a cutting tool, all of which have a simple structure, a low number of parts, are easy to manufacture, have fewer shape limitations, are easily adaptable to miniaturization, and have a wide range of balance adjustment. [Means for solving the problem]

[0009] To solve the above problems, the present invention provides the following means.

[0010] [Aspect 1 of the present invention] A rotating body with a dynamic balance adjustment mechanism, comprising: a main body that can be rotated about a central axis; a flow channel provided in the main body and extending in the circumferential direction; a dilatant fluid that fills the flow channel; and a weight housed in the flow channel, wherein the weight is movable within the liquid dilatant fluid when the magnitude of the acceleration acting on the dilatant fluid due to the rotation of the main body is less than a predetermined value, and is held in place by the solidified dilatant fluid when the magnitude of the acceleration exceeds the predetermined value.

[0011] In the rotating body with a dynamic balance adjustment mechanism of the present invention, a dilatant fluid is filled into a flow channel that is arranged in the main body and extends in the circumferential direction. A dilatant fluid is a fluid whose viscosity during flow depends on the shear rate and shear stress. Specifically, the dilatant fluid of the present invention exhibits liquid properties when the magnitude of acceleration is less than a predetermined value, and solid properties when the magnitude of acceleration is greater than or equal to a predetermined value. The above "acceleration" corresponds to the rate of change of velocity per unit time. Although "acceleration" is a vector quantity, the dilatant fluid changes its properties (liquid or solid) according to the magnitude of the acceleration, regardless of the direction of the acceleration.

[0012] When the main body is being rotated but the magnitude of the acceleration is below a predetermined value, and the dilatant fluid is in a liquid state, the weight placed in the dilatant fluid moves within the dilatant fluid to a position where the rotational balance of the rotating body is in equilibrium (to balance with the centrifugal force). Furthermore, when the rotational balance is in equilibrium, and the magnitude of the acceleration exceeds a predetermined value, and the dilatant fluid solidifies, the weight is fixed and held in place by the dilatant fluid (held immobile within the dilatant fluid).

[0013] More specifically, the rotating body with the dynamic balance adjustment mechanism of the present invention can be used, for example, as follows. First, the rotating body is rotated at a low speed while gradually increasing its velocity, moving the weight in the dilatant fluid to the equilibrium position (the position where the rotational balance is equilibrium). Next, the rotating body is rotated for a certain period of time while maintaining the low speed, stabilizing the weight in the equilibrium position. Then, the rotation of the rotating body is rapidly accelerated (to a high speed) to increase the shear stress, solidify the dilatant fluid, and hold the weight in the equilibrium position. In this way, the rotating body is brought into a state of dynamic rotational balance.

[0014] Therefore, according to the present invention, even when conditions such as rotational conditions change, it is possible to automatically correct dynamic imbalances such as swinging during rotation by following those changes.

[0015] Furthermore, unlike conventional balance adjustment mechanisms that use complex structures or a large number of parts, this invention uses a simple structure to minimize the number of parts, making it easy to achieve dynamic balance of a rotating body. This also simplifies manufacturing.

[0016] Furthermore, in this invention, if it is possible to provide a circumferentially extending channel in the main body, the dilatant fluid and weights can be placed within the channel to achieve the excellent effects described above. Therefore, it is less restricted by shape and can flexibly respond to the demand for miniaturization. When providing a circumferentially extending channel in the main body, for example, metal additive manufacturing technology can be used. This further reduces the limitations on the channel shape and makes it possible to fabricate even complex channel shapes in a single process.

[0017] Furthermore, in this invention, the range of balance adjustment can be easily expanded by appropriately adjusting the number, size, and specific gravity of the weights placed in the flow path. Alternatively, the range of balance adjustment can also be expanded by appropriately setting the shape of the flow path.

[0018] Based on the above, the present invention offers a simple structure, a low number of parts, ease of manufacturing, fewer limitations due to shape, easy miniaturization, and a wider range of adjustable balance.

[0019] [Aspect 2 of the present invention] The rotating body with a dynamic balance adjustment mechanism according to embodiment 1, wherein the flow path has an annular first flow path extending over the entire circumference in the circumferential direction.

[0020] In this case, the weight is made movable within the first channel along the entire circumference around the central axis. This allows for a more stable expansion of the range over which balance can be adjusted.

[0021] [Aspect 3 of the present invention] The flow path has a first flow path extending in the circumferential direction and a second flow path connected to at least a part of the circumferential direction of the first flow path and extending from the first flow path in at least one of the axial direction and the radial direction. The rotating body with a dynamic balance adjustment mechanism according to Embodiment 1 or 2.

[0022] In this case, at the location where the first flow path and the second flow path are connected, the internal volume (cross-sectional area) of the flow path is made larger than that of the first flow path alone. With this configuration, it is possible to easily arrange weights at the location where the first flow path and the second flow path are connected. That is, it is possible to easily cause imbalance at a predetermined location in the circumferential direction of the rotating body, thereby facilitating the achievement of rotational balance and expanding the weight adjustment range. <0000_{090}><0000_{091}><0000_{092}>〔Aspect 4 of the present invention〕<0000_{093}>The rotating body with a dynamic balance adjustment mechanism according to Embodiment 3, wherein a plurality of the second flow paths are provided at intervals in the circumferential direction. <0000_{094}><0000_{095}><0000_{096}>In this case, a plurality of locations where the first flow path and the second flow path are connected (locations where the internal space of the flow path becomes wider) are provided at intervals in the circumferential direction. Therefore, it is possible to easily cause imbalance at a predetermined location (a plurality of locations) in the circumferential direction of the rotating body, and the above-described effects are achieved more stably. <0000_{097}><0000_{098}><0000_{099}>〔Aspect 5 of the present invention〕<0000_{100}>The flow path has a bottom portion located at the lowermost part of the flow path and an inclined surface disposed above the bottom portion and extending upward as it goes radially from the bottom portion. The rotating body with a dynamic balance adjustment mechanism according to any one of Embodiments 1 to 4. <0000_{101}><0000_{102}><0000_{103}>In this case, when the rotating body is rotated, the weight in the flow path moves along the inclined surface upwards and radially outward (or inward) from the bottom due to centrifugal force, etc. Also, when the rotation of the rotating body stops, the weight in the flow path is guided along the inclined surface by gravity and returned to the bottom. With the above configuration, each time the stationary rotating body is rotated, the weight moves to the appropriate position where the rotational balance is equilibrium, so the rotational balance of the rotating body can be maintained with high precision and stability.

[0027] [Aspect 6 of the present invention] The aforementioned flow channels are provided in multiple locations spaced apart from each other in the circumferential direction, and the rotating body with a dynamic balance adjustment mechanism is as described in any one of embodiments 1 to 5.

[0028] In this case, the degree of freedom in arranging (layout) the flow channels is increased. Even if the shape of the rotating body is not cylindrical or cylindrical, but rather polygonal columnar or polygonal cylindrical, the flow channels can be easily arranged to match the shape of the body.

[0029] Furthermore, with the above configuration, even if, for example, the central axis of the rotating body is tilted relative to the vertical or extends horizontally, problems such as the weight being unevenly distributed in one place due to gravity within the main body are suppressed. In other words, because the weight is distributed in each flow path of the main body, it is easier to maintain a stable rotational balance regardless of the orientation of the rotating body.

[0030] [Aspect 7 of the present invention] A rotating body with a dynamic balance adjustment mechanism according to any one of embodiments 1 to 6, wherein the circumferential dimension of the flow path increases as it moves radially outward.

[0031] In this case, when the rotating body rotates and the weight in the flow path moves radially outward due to centrifugal force, a large degree of freedom (the range in which the weight can move freely in the circumferential direction) is ensured for the circumferential movement of the weight. This allows for a stable expansion of the range in which balance can be adjusted.

[0032] [Aspect 8 of the present invention] The aforementioned flow channels are provided in multiple locations spaced apart from each other in the axial direction, and the rotating body with a dynamic balance adjustment mechanism is as described in any one of embodiments 1 to 7.

[0033] With the above configuration, for example, even when the axial dimension (L) of the rotating body is larger than the outer diameter (D) (i.e., when the body has an elongated shape in the axial direction), the rotational balance of the rotating body can be stably balanced by the multiple flow channels arranged at intervals in the axial direction, and the dilatant fluid and weights placed in each flow channel. In particular, when the above configuration is used for cutting tools with a large L / D ratio, it is possible to stably improve cutting accuracy and effectively extend tool life.

[0034] [Aspect 9 of the present invention] The rotating body with a dynamic balance adjustment mechanism according to any one of embodiments 1 to 8, wherein the weight is spherical or granular.

[0035] In this case, the weight moves more smoothly within the flow path. The smoothly moving weight allows for the rotational balance of the rotating body to be balanced quickly and stably.

[0036] [Aspect 10 of the present invention] A method for adjusting the dynamic balance of a rotating body using a rotating body with a dynamic balance adjustment mechanism described in any one of embodiments 1 to 9, comprising: a balance adjustment step of rotating the body around the central axis while keeping the magnitude of the acceleration below a predetermined value, and moving the weight so that the rotational balance is in equilibrium within the liquid dilatant fluid; and a balance holding step of rotating the body around the central axis while keeping the magnitude of the acceleration above a predetermined value, and holding the weight with the solidified dilatant fluid.

[0037] The dynamic balancing method for a rotating body of the present invention comprises a balancing step and a balance maintenance step in that order. This achieves the same excellent effects as the rotating body with the dynamic balancing mechanism described above.

[0038] [Aspect 11 of the present invention] The dynamic balancing method for a rotating body according to embodiment 10, wherein the balancing step involves alternately rotating the main body in forward and reverse directions on one circumferential side and the other circumferential side around the central axis.

[0039] In this case, the rotational balance of the rotating body can be balanced with higher precision during the balancing process.

[0040] [Aspect 12 of the present invention] A cutting tool with a dynamic balancing mechanism, comprising: a tool body that can be rotated around a central axis; a flow channel provided in the tool body and extending in the circumferential direction; a dilatant fluid filled in the flow channel; and a weight housed in the flow channel, wherein the weight is movable within the liquid dilatant fluid when the magnitude of the acceleration acting on the dilatant fluid due to the rotation of the tool body is less than a predetermined value, and is held in place by the solidified dilatant fluid when the magnitude of the acceleration exceeds the predetermined value.

[0041] The cutting tool with a dynamic balancing mechanism of the present invention achieves the same excellent effects as the rotating body with a dynamic balancing mechanism described above. In particular, it enables accurate and stable dynamic rotational balancing in cutting tools used under harsh conditions, among the various types of rotating bodies. As a result, cutting accuracy can be stably improved, and tool life can be extended.

[0042] [Aspect 13 of the present invention] A method for adjusting the dynamic balance of a cutting tool using the cutting tool with a dynamic balance adjustment mechanism described in Embodiment 12, comprising: a balance adjustment step of rotating the tool body around the central axis while keeping the magnitude of the acceleration below a predetermined value, and moving the weight so that the rotational balance is in equilibrium within the liquid dilatant fluid; and a balance holding step of rotating the tool body around the central axis while keeping the magnitude of the acceleration above a predetermined value, and holding the weight with the solidified dilatant fluid.

[0043] The dynamic balancing method for cutting tools of the present invention comprises a balancing step and a balance maintenance step in that order. This achieves the same excellent performance as the cutting tool with the dynamic balancing mechanism described above. [Effects of the Invention]

[0044] According to the above-mentioned aspects of the present invention, a rotating body with a dynamic balancing mechanism, a method for dynamically balancing a rotating body, a cutting tool with a dynamic balancing mechanism, and a method for dynamically balancing a cutting tool are provided, which have a simple structure, a small number of parts, are easy to manufacture, have fewer shape limitations, are easy to miniaturize, and have a wide range of balance adjustments. [Brief explanation of the drawing]

[0045] [Figure 1] Figure 1 is a schematic perspective view showing a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to a first embodiment of the present invention. [Figure 2] Figure 2 is a schematic side view showing a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to the first embodiment. [Figure 3] Figure 3 is a schematic cross-sectional view (longitudinal cross-sectional view) of a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to the first embodiment. [Figure 4] Figure 4 is a schematic bottom view showing a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to the first embodiment. [Figure 5] Figure 5 is a graph illustrating the magnitude of the acceleration (relationship between velocity and time) acting on the dilatant fluid as the tool body (main body) is rotated. [Figure 6]Figure 6(a) is a schematic cross-sectional view showing the flow path, liquid dilatant fluid, and weight when the tool body is stopped rotating; Figure 6(b) is a schematic cross-sectional view showing the flow path, liquid dilatant fluid, and weight when the tool body is rotating at a low rotational speed; and Figure 6(c) is a schematic cross-sectional view showing the flow path, solidified dilatant fluid, and weight when the tool body is rotating at a high rotational speed. [Figure 7] Figure 7 is a schematic perspective view showing a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to a second embodiment of the present invention. [Figure 8] Figure 8 is a schematic side view showing a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to the second embodiment. [Figure 9] Figure 9 is a schematic cross-sectional view (longitudinal cross-sectional view) of a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to the second embodiment. [Figure 10] Figure 10 is a schematic bottom view showing a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to the second embodiment. [Figure 11] Figure 11 is a schematic perspective view showing a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to a third embodiment of the present invention. [Figure 12] Figure 12 is a schematic side view showing a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to the third embodiment. [Figure 13] Figure 13 is a schematic cross-sectional view (longitudinal cross-sectional view) of a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to the third embodiment. [Figure 14] Figure 14 is a schematic bottom view showing a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to the third embodiment. [Figure 15] Figure 15 is a schematic perspective view showing a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to a fourth embodiment of the present invention. [Figure 16]Figure 16 is a schematic side view showing a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to the fourth embodiment. [Figure 17] Figure 17 is a schematic cross-sectional view (longitudinal cross-sectional view) of a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to the fourth embodiment. [Figure 18] Figure 18 is a schematic bottom view showing a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to the fourth embodiment. [Figure 19] Figure 19 is a schematic perspective view showing a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to the fifth embodiment of the present invention. [Figure 20] Figure 20 is a schematic side view showing a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to the fifth embodiment. [Figure 21] Figure 21 is a schematic cross-sectional view (longitudinal cross-sectional view) of a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to the fifth embodiment. [Figure 22] Figure 22 is a schematic bottom view showing a cutting tool with a dynamic balancing mechanism (rotating body with a dynamic balancing mechanism) according to the fifth embodiment. [Modes for carrying out the invention]

[0046] The rotating body 10 with a dynamic balance adjustment mechanism of the present invention will be described below, with reference to the cutting tools 10A to 10E with dynamic balance adjustment mechanisms of the first to fifth embodiments. In the description of the embodiments, the rotating body 10 with a dynamic balance adjustment mechanism may be simply referred to as the rotating body 10. Similarly, the cutting tools 10A to 10E with dynamic balance adjustment mechanisms may be simply referred to as the cutting tools 10A to 10E or tools, etc.

[0047] Cutting tools 10A to 10E with a dynamic balancing mechanism are milling tools (turning tools) that cut into the workpiece while being rotated around the central axis O by the spindle of a machine tool or the like. Specifically, cutting tools 10A to 10E are, for example, replaceable-tip cutters and replaceable-tip end mills. Note that in the drawings used for each embodiment, the shape of the tool is simplified and shown schematically.

[0048] <First Embodiment> A cutting tool 10A with a dynamic balance adjustment mechanism (rotating body 10 with a dynamic balance adjustment mechanism) and a method for dynamically adjusting the balance of the cutting tool 10A (method for dynamically adjusting the balance of the rotating body 10) according to the first embodiment of the present invention will be described with reference to Figures 1 to 6.

[0049] As shown in Figures 1 to 4 and Figure 6, the cutting tool 10A with a dynamic balancing mechanism comprises a tool body (main body) 1 that is rotated around a central axis O by the spindle of a machine tool (not shown), one or more cutting inserts (not shown) that are detachably attached to the tool body 1, a flow path 2 provided in the tool body 1, a dilatant fluid 3 that fills the flow path 2, and a weight 4 that is housed in the flow path 2. Note that the weight 4 is not shown in Figures 1 to 4. The tool body 1 is substantially cylindrical or substantially cylindrical in shape with the central axis O as the center.

[0050] [Definition of direction] In this embodiment, the direction in which the central axis O of the tool body 1 extends, that is, the direction along the central axis O, is called the axial direction. Of the two ends of the tool body 1 in the axial direction, a cutting insert (not shown) is placed at the first end 1a, and a spindle of a machine tool (not shown) is attached to the second end 1b. In the axial direction, the direction from the second end 1b of the tool body 1 toward the first end 1a is called the axial front end side or simply the front end side, and the direction from the first end 1a toward the second end 1b is called the axial rear end side or simply the rear end side.

[0051] In this embodiment, the central axis O extends vertically. Therefore, the axial direction can also be described as the up-and-down direction. The first end 1a corresponds to the lower end of the tool body 1, and the second end 1b corresponds to the upper end of the tool body 1. The axial tip side corresponds to the lower side, and the axial rear end side corresponds to the upper side.

[0052] Furthermore, the direction perpendicular to the central axis O is called the radial direction. Within the radial direction, the direction approaching the central axis O is called the radially inward direction, and the direction moving away from the central axis O is called the radially outward direction.

[0053] Furthermore, the direction of rotation around the central axis O is called the circumferential direction. Of the circumferential directions, the direction in which the tool body 1 is rotated when cutting into the workpiece (one side of the circumferential direction) is called the tool rotation direction T, and the opposite rotation direction (the other side of the circumferential direction) is called the opposite side of the tool rotation direction T or the anti-tool rotation direction. In this embodiment, as shown in Figure 4, in a bottom view of the tool viewed from the axial tip side (i.e., a view of the tool tip from the axial tip side), the counterclockwise rotation direction around the central axis O corresponds to the tool rotation direction T, and the clockwise rotation direction corresponds to the opposite tool rotation direction.

[0054] [Cutting inserts] The cutting insert is made of a hard sintered body, such as cemented carbide. Although not specifically shown in the figures, in this embodiment, multiple cutting inserts are provided on the outer circumference of the tip of the tool body 1 at intervals from each other in the circumferential direction. For example, three cutting inserts are provided on the outer circumference of the tip of the tool body 1 at equal pitches in the circumferential direction. Note that the number of cutting inserts is not limited to three; it may be two, four or more.

[0055] Each cutting insert has a cutting edge. When the cutting insert is attached to the tool body 1, the cutting edge protrudes from the tip of the tool body 1 toward the tip, and also protrudes radially outward from the outer circumference of the tool body 1. The outer diameter dimension of the rotational trajectory (rotational trajectory of the cutting edge) obtained by rotating the cutting edge together with the tool body 1 around the central axis O corresponds to the cutting edge diameter dimension of the tool.

[0056] [Tool body] The tool body 1 is made of metal, such as steel. The tool body 1 is detachably mounted on the spindle of a machine tool (not shown). The tool body 1 is rotated by the spindle of the machine tool in the tool rotation direction T around the central axis O. During cutting, the tool body 1 is also fed radially by the spindle of the machine tool. In this way, by rotating the tool body 1 and providing feed, the cutting edge of the cutting insert attached to the tool body 1 cuts into the workpiece, and various milling operations are performed.

[0057] As shown in Figures 1 to 4, in this embodiment, the tool body 1 has a multi-stage cylindrical or multi-stage columnar shape centered on the central axis O. Specifically, the outer diameter of the axial tip portion (first end portion 1a) of the tool body 1 where the cutting insert (cutting edge) is placed is the largest, and the outer diameter of the axial rear end portion (second end portion 1b) which is attached to the spindle is the smallest. In addition, the intermediate portion of the tool body 1 located between the axial tip portion and the axial rear end portion has a tapered shape that gradually widens in diameter towards the axial tip side.

[0058] Although not specifically shown in the figures, the tool body 1 has a plurality of insert mounting seats arranged circumferentially at intervals from each other on the outer circumference of the tip of the tool body 1, to which each cutting insert is detachably attached, and a plurality of chip pockets that are recessed from the tip surface and outer circumference of the tool body 1 and are formed extending in the tool rotation direction T and to the rear end in the axial direction of each insert mounting seat. The number of insert mounting seats and the number of chip pockets are the same as the number of cutting inserts. The other configurations of the insert mounting seats and chip pockets will be described separately in the fifth embodiment.

[0059] Although not specifically shown in the diagram, the tool body 1 has an inlet for injecting the dilatant fluid 3 and weight 4 into the channel 2 from outside the tool. After the dilatant fluid 3 and weight 4 are injected into the channel 2, the inlet is closed by a plug member or the like, thereby sealing the channel 2 in a liquid-tight manner.

[0060] The tool body 1 also has a mounting hole 11 that penetrates the tool body 1 in the axial direction. In this embodiment, the mounting hole 11 is a multi-stage circular hole, and the inner diameter is gradually reduced towards the axial tip. A mounting bolt (not shown) is inserted through the mounting hole 11 and screwed onto the spindle of the machine tool. In this way, the tool body 1 is fixed to the spindle.

[0061] [Flow path] The flow path 2 is provided in the tool body (body) 1 and extends in the circumferential direction. In this embodiment, the flow path 2 is located inside the tool body 1. Specifically, the flow path 2 is located in the part of the tool body 1 with the largest outer diameter (axial tip). The flow path 2 is located on the outer circumference of the tip of the tool body 1. The flow path 2 in this embodiment is annular in shape with a central axis O, and specifically, it is a substantially circular ring shape. The diameter of the flow path 2 is larger than the outer diameter of the axial rear end (second end 1b) of the tool body 1. The flow path 2 is formed inside the tool body 1 by, for example, metal additive manufacturing technology using a 3D printer.

[0062] The flow path 2 includes a first flow path 21 extending in the circumferential direction, and a second flow path 22 connected to at least a portion of the first flow path 21 in the circumferential direction and extending from the first flow path 21 in at least one of the axial and radial directions.

[0063] In this embodiment, the first channel 21 has an annular shape that extends over the entire circumference in the circumferential direction, and specifically, it has an annular shape centered on the central axis O. As shown in Figure 3, in a longitudinal cross-sectional view of the tool along the central axis O, the cross-sectional shape of the first channel 21 is circular.

[0064] The second channel 22 is connected to the rear end portion (upper portion) of the first channel 21. As shown in Figure 4, in this embodiment, multiple second channels 22 are provided spaced apart from each other in the circumferential direction. Each of the multiple second channels 22 is connected to a part of the first channel 21 in the circumferential direction. Each second channel 22 extends in the circumferential direction. Each second channel 22 communicates with each other via the first channel 21.

[0065] For example, three second flow channels 22 are provided at equal pitches in the circumferential direction. The number of second flow channels 22 is not limited to three; it may be two, four, or more. Preferably, the number of second flow channels 22 is the same as the number of cutting inserts, or a multiple or divisor of the number of cutting inserts.

[0066] As shown in Figure 4, the circumferential dimension of each second channel 22 increases towards the radially outward direction. Also, as shown in Figure 3, the second channel 22 widens from the connection point with the first channel 21 toward the axial rear end (upper side) and radially outward. In the longitudinal cross-sectional view of the tool shown in Figure 3, the second channel 22 has a roughly trapezoidal shape. The radial dimension of the second channel 22 increases toward the axial rear end.

[0067] The flow path 2 also has a bottom portion 21a located at the lowest part of the flow path 2, and an inclined surface 22a positioned above the bottom portion 21a and extending upward radially from the bottom portion 21a. In this embodiment, the bottom portion 21a is located in the first flow path 21, and the inclined surface 22a is located in the second flow path 22. The inclined surface 22a also extends upward radially outward from the bottom portion 21a. Therefore, the inclined surface 22a faces radially inward and upward. Specifically, the inclined surface 22a has a concave curved surface shape extending in the circumferential direction (see Figure 1). In the longitudinal cross-sectional view shown in Figure 3, the inclined surface 22a extends in a straight line.

[0068] [Dilatant fluid] The dilatant fluid 3 is filled within the channel 2. However, the dilatant fluid 3 may also be filled within the channel 2 with some gaps (gaps where air, etc., can be placed). The dilatant fluid 3 does not flow out of the channel 2 due to the rotation of the tool body 1, etc., and is contained within the channel 2 in a sealed state.

[0069] The dilatant fluid 3 is a fluid whose viscosity during flow depends on the shear rate and shear stress. In this embodiment, the dilatant fluid 3 exhibits liquid properties when the magnitude of the acceleration acting on the dilatant fluid 3 due to the rotation of the tool body 1 is less than a predetermined value (the regions S1 and S2 shown in the graph of Figure 5, i.e., the regions where the slope of the graph is gentle). Conversely, when the magnitude of the acceleration acting on the dilatant fluid 3 due to the rotation of the tool body 1 is greater than or equal to a predetermined value (the region S3 shown in the graph of Figure 5, i.e., the region where the slope of the graph is steep), it exhibits solid properties. Note that the above "acceleration" corresponds to the rate of change of velocity per unit time. Although "acceleration" is a vector quantity, the dilatant fluid 3 changes its properties (liquid or solid) according to the magnitude of the acceleration, regardless of the direction of the acceleration. In this embodiment, the "magnitude of acceleration" acting on the dilatant fluid 3 due to the rotation of the tool body 1 may be appropriately rephrased as "magnitude of centrifugal force."

[0070] The dilatant fluid 3 is also called dilatancy or spherical suspension. The dilatant fluid 3 is composed of, for example, a mixture of any liquid and any solid particles that are insoluble or sparingly soluble in that liquid. The solid particles include suspended matter. The properties of the dilatant fluid 3 are particularly evident in spherical objects. Therefore, it is preferable that the solid particles include spherical suspended matter. The solid particles contained in the dilatant fluid 3 may include, for example, starches such as potato starch and corn starch, and other carbohydrates. Alternatively, the solid particles contained in the dilatant fluid 3 may be inorganic materials such as silicon dioxide, silicates, titanium dioxide, cellulose, organosilicon produced from boric acid, alumina particles, silica particles, titania, zirconia, calcia (calcium oxide), calcium carbonate, sand, corn starch, potato starch, wheat flour and other grains, and other materials, either alone or in appropriate combinations.

[0071] The liquid contained in the dilatant fluid 3 may include, for example, water and alcohol. The liquid contained in the dilatant fluid 3 may be, for example, water, alcohol, organic solvent, other liquids, or any combination thereof.

[0072] When the dilatant fluid 3 is at normal pressure, such as when the tool body 1 is stopped rotating, fine molecules of liquid such as water fill the spaces between the molecules of the suspended material, such as spherical suspended material like potato starch, causing the fluid to exhibit liquid-like properties overall. On the other hand, when an instantaneous external force is applied to the dilatant fluid 3, such as when the tool body 1 is rapidly rotated at high speed, the arrangement of the molecules of the spherical suspended material changes, and the viscosity increases significantly as molecules of water or other liquids fill the spaces between the molecules of the spherical suspended material, causing the fluid to exhibit solid-like properties overall. Furthermore, when a predetermined pressure is applied to the dilatant fluid 3 for a certain period of time, such as when the tool body 1 is rotated at a high speed, the liquid molecules that have filled the spaces between the molecules of the spherical suspended material move in response to the pressure, causing the molecules of the spherical suspended material to aggregate, increasing the viscosity and hardening the fluid as a whole, and causing it to exhibit solid-like properties.

[0073] When the applied predetermined pressure of the dilatant fluid 3 is reduced or removed, its viscosity decreases in proportion to the pressure, and it once again exhibits liquid-like properties. The cutting tool 10A (rotating body 10) according to this embodiment utilizes the properties of the dilatant fluid 3 described above. Furthermore, the shape of the particles contained in the dilatant fluid 3 (solid particles that constitute part of the dilatant fluid 3) is not particularly limited and may be spherical or needle-shaped, for example. The particles contained in the dilatant fluid 3 may be not only perfectly spherical but also amorphous crushed metal oxides. The dilatant fluid 3 may also be formed by dispersing particles of acrylic acid ester-styrene copolymer in water or other liquids. The liquid contained in the dilatant fluid 3 may be silicone oil or other silicone media. In addition to the components that provide the properties of a dilatant member, the dilatant fluid 3 may be arbitrarily combined with other components, such as fibers, colorants, lubricants, fillers, plasticizers, and diluents, as well as other appropriate components.

[0074] [Weight] The weight 4 is made of, for example, metal such as steel or a hard sintered body such as cemented carbide. Preferably, the weight 4 is made of a material whose specific gravity is equal to or greater than that of the tool body 1. As shown in Figures 6(a) to (c), the weight 4 is placed in the flow path 2.

[0075] Here, Figure 6(a) schematically represents the liquid dilatant fluid 3 and weight 4 in the flow path 2 when the tool body 1 is stopped rotating. Figure 6(b) schematically represents the liquid dilatant fluid 3 and weight 4 in the flow path 2 when the tool body 1 is rotating and the magnitude of the acceleration acting on the dilatant fluid 3 is less than a predetermined value (the tool body 1 is rotating at a low rotational speed). Figure 6(c) schematically represents the solidified dilatant fluid 3 and weight 4 in the flow path 2 when the tool body 1 is rotating and the magnitude of the acceleration acting on the dilatant fluid 3 is greater than or equal to a predetermined value (the tool body 1 is rotating at a high rotational speed).

[0076] The weight 4 is, for example, spherical or granular. One or more weights 4 are provided in the flow path 2, and in this embodiment, multiple weights 4 are provided. The multiple weights 4 are identical in shape and dimensions to each other, i.e., they are common parts.

[0077] The weight 4 is allowed to move freely within the flow path 2 when the dilatant fluid 3 is in liquid form. When the dilatant fluid 3 is in solid form, the weight 4 is fixed within the flow path 2 by the dilatant fluid 3 and becomes immovable. More specifically, the weight 4 is allowed to move within the liquid dilatant fluid 3 when the magnitude of the acceleration acting on the dilatant fluid 3 due to the rotation of the tool body (main body) 1 is less than a predetermined value, and is held in place by the solidified dilatant fluid 3 when the magnitude of the acceleration exceeds the predetermined value.

[0078] [Method for dynamic balancing of cutting tools (rotating bodies)] Next, a method for adjusting the dynamic balance of the cutting tool 10A (rotating body 10) with the dynamic balance adjustment mechanism described above will be explained with reference to Figure 5.

[0079] Here, the graph shown in Figure 5 represents the magnitude of the acceleration (relationship between velocity and time) acting on the dilatant fluid 3 in the flow path 2 as the tool body 1 is rotated. Specifically, in region S1 shown in the graph of Figure 5, the rate of increase (rate of change) of velocity per unit time is small (the rate of increase of velocity is below the threshold), and the magnitude of the acceleration acting on the dilatant fluid 3 is below a predetermined value. Also, in region S2 shown in the graph of Figure 5, the velocity is kept constant for a certain period of time, and again, the magnitude of the acceleration acting on the dilatant fluid 3 is below a predetermined value. Furthermore, in region S3 shown in the graph of Figure 5, the rate of increase (rate of change) of velocity per unit time is large (the rate of increase of velocity is above the threshold), and the magnitude of the acceleration acting on the dilatant fluid 3 is above a predetermined value.

[0080] Furthermore, the dynamic balance adjustment method for the cutting tool 10A (rotating body 10) of this embodiment includes a balance adjustment step in which the tool body (main body) 1 is rotated around the central axis O while keeping the magnitude of the acceleration below a predetermined value, and the weight 4 is moved so that the rotational balance is in equilibrium within the liquid dilatant fluid 3; and a balance holding step in which the tool body (main body) 1 is rotated around the central axis O while keeping the magnitude of the acceleration above a predetermined value, and the weight 4 is held by the solidified dilatant fluid 3.

[0081] More specifically, the above balance adjustment process comprises, in this order, a first adjustment step in which the tool body 1 is rotated so that the rate of increase of the velocity per unit time acting on the dilatant fluid 3 is less than a threshold, as shown in region S1 of Figure 5, and a second adjustment step in which the tool body 1 is rotated so that the velocity is constant, as shown in region S2 of Figure 5. Specifically, in the first adjustment step, the tool body 1 is rotated while gradually increasing the velocity to move the weight 4 to the equilibrium position of the rotational balance. In the second adjustment step, the tool body 1 is rotated at a low rotational speed for a certain period of time to stabilize the weight 4 at the equilibrium position.

[0082] After the second adjustment step, in the balance holding step, as shown in region S3 of Figure 5, the tool body 1 is rotated at a high rotational speed while rapidly increasing its speed (the tool body 1 is rotated so that the rate of increase of the speed per unit time acting on the dilatant fluid 3 exceeds a threshold), thereby increasing the shear stress to solidify the dilatant fluid 3 and fixing the weight 4 in the equilibrium position.

[0083] [Effects of this embodiment] In the cutting tool 10A (rotating body 10 with dynamic balance adjustment mechanism) of this embodiment described above, a dilatant fluid 3 is filled into a flow path 2 that is located in the tool body (main body) 1 and extends in the circumferential direction.

[0084] When the tool body 1 is being rotated but the magnitude of the acceleration is less than a predetermined value, and the dilatant fluid 3 is in a liquid state, the weight 4 placed in the dilatant fluid 3 moves within the dilatant fluid 3 to a position where the rotational balance of the tool is in equilibrium (to balance with the centrifugal force). Furthermore, when the rotational balance is in equilibrium, and the magnitude of the acceleration exceeds a predetermined value, and the dilatant fluid 3 solidifies, the weight 4 is fixed and held in place by the dilatant fluid 3 (held immobile within the dilatant fluid 3).

[0085] Therefore, according to this embodiment, even when conditions such as rotational conditions change, the dynamic imbalance such as swinging during rotation can be automatically corrected in response to those changes.

[0086] Furthermore, unlike conventional balance adjustment mechanisms that use complex structures or a large number of parts, this embodiment allows for easy dynamic balancing of the cutting tool 10A (rotating body 10) by keeping the number of parts to a minimum through a simple structure. This also simplifies manufacturing.

[0087] Furthermore, in this embodiment, if it is possible to provide a circumferentially extending channel 2 in the tool body (main body) 1, the dilatant fluid 3 and weight 4 can be placed in the channel 2 to achieve the excellent effects described above. Therefore, it is less restricted by shape and can flexibly respond to the demand for miniaturization. When providing the circumferentially extending channel 2 in the tool body 1, for example, metal additive manufacturing technology can be used. This further reduces the restrictions on the channel shape and makes it possible to fabricate even complex channel shapes in a single process.

[0088] Furthermore, in this embodiment, the range of balance adjustment can be easily expanded by appropriately adjusting the number, size, specific gravity, etc., of the weights 4 placed in the flow path 2. Alternatively, the range of balance adjustment can also be expanded by appropriately setting the shape of the flow path 2.

[0089] Based on the above, according to this embodiment, the structure is simple, the number of parts is kept low, manufacturing is easy, there are fewer restrictions due to shape, miniaturization is easy, and the range of balance adjustment can be expanded. In particular, among the types of rotating bodies 10, cutting tools 10A, which are used under harsh conditions, can achieve accurate and stable dynamic rotational balance. As a result, cutting accuracy can be consistently improved, and tool life can be extended.

[0090] In this embodiment, the flow path 2 has an annular first flow path 21 that extends around the entire circumference. In this case, the weight 4 is made movable within the first channel 21 over the entire circumference around the central axis O. This allows for a more stable expansion of the range over which balance can be adjusted.

[0091] Furthermore, the first channel 21 is not limited to an annular shape extending over the entire circumference. Although not specifically shown in the figures, the first channel 21 may be in the shape of a circular arc extending in the circumference. In this case, multiple first channels 21 may be provided side by side in the circumference. When multiple first channels 21 are arranged over substantially the entire circumference, the same effects as in the embodiment described above can be obtained. Moreover, even if, for example, the central axis O of the cutting tool 10A (rotating body 10) is tilted with respect to the vertical or extends horizontally, problems such as the weight 4 being unevenly distributed in one place due to gravity within the tool body 1 are suppressed. That is, because the weight 4 is distributed in each of the first channels 21 of the tool body 1, the rotational balance can be easily stabilized and balanced regardless of the orientation of the tool.

[0092] In this embodiment, the flow path 2 includes a first flow path 21 extending in the circumferential direction, and a second flow path 22 connected to at least a portion of the first flow path 21 in the circumferential direction and extending from the first flow path 21 in at least one of the axial and radial directions.

[0093] In this case, at the point where the first channel 21 and the second channel 22 are connected, the internal volume (cross-sectional area) of channel 2 is larger than that of the first channel 21 alone. This configuration makes it easier to place the weight 4 at the point where the first channel 21 and the second channel 22 are connected. In other words, it is easier to shift the balance to a predetermined point in the circumferential direction of the cutting tool 10A (rotating body 10), thereby making it easier to achieve rotational balance and expanding the weight adjustment range.

[0094] In this embodiment, multiple second flow channels 22 are provided at intervals from each other in the circumferential direction. In this case, multiple points where the first flow path 21 and the second flow path 22 are connected (points where the internal space of the flow path 2 widens) are provided at intervals from each other in the circumferential direction. Therefore, it is possible to make it easier to bias the balance of the cutting tool 10A (rotating body 10) to predetermined points (multiple points) in the circumferential direction, and the above-mentioned effects are achieved more stably. Furthermore, it is preferable that the number and arrangement of the second flow channels 22 be appropriately set according to, for example, the number and arrangement of cutting inserts, insert mounting seats, and chip pockets provided on the cutting tool 10A.

[0095] In this embodiment, the circumferential dimension of the second flow path 22 increases as it moves radially outward. In this case, when the cutting tool 10A (rotating body 10) rotates and the weight 4 in the second flow path 22 moves radially outward due to centrifugal force, a large degree of freedom (range in which the weight 4 can move freely in the circumferential direction) is ensured. This allows for a stable expansion of the range in which balance can be adjusted.

[0096] In this embodiment, the flow path 2 has a bottom portion 21a located at the lowest part of the flow path 2, and an inclined surface 22a positioned above the bottom portion 21a and extending upward radially from the bottom portion 21a.

[0097] In this case, when the cutting tool 10A (rotating body 10) is rotated, the weight 4 in the flow path 2 moves along the inclined surface 22a upwards and radially outward from the bottom 21a due to centrifugal force, etc. Also, when the rotation of the cutting tool 10A stops, the weight 4 in the flow path 2 is guided along the inclined surface 22a by gravity and returns to the bottom 21a. With the above configuration, each time the stationary cutting tool 10A is rotated, the weight 4 moves to the appropriate position where the rotational balance is equilibrium, so that the rotational balance of the tool can be stably balanced with high precision.

[0098] In this embodiment, the weight 4 is spherical or granular. In this case, the weight 4 moves more smoothly within the flow path 2. The smoothly moving weight 4 allows for the rotational balance of the cutting tool 10A (rotating body 10) to be balanced quickly and stably.

[0099] Furthermore, if the specific gravity of the weight 4 is greater than the specific gravity of the tool body 1, the rotational balance of the tool can be stably maintained even if the tool body 1 is made of a heavy material such as steel. In addition, the outer diameter of the weight 4 can be kept small, making further miniaturization of the balance adjustment mechanism possible.

[0100] Furthermore, the dynamic balancing method for the cutting tool 10A (dynamic balancing method for the rotating body 10) of this embodiment includes a balancing step and a balance holding step in that order. This achieves the same excellent effects as the cutting tool 10A (rotating body 10 with dynamic balancing mechanism) described above.

[0101] <Second Embodiment> Next, a cutting tool 10B with a dynamic balance adjustment mechanism (rotating body 10 with a dynamic balance adjustment mechanism) and a method for dynamically adjusting the balance of the cutting tool 10B (method for dynamically adjusting the balance of the rotating body 10) according to a second embodiment of the present invention will be described with reference to Figures 7 to 10. In this embodiment, the same components as in the previously described embodiment may be given the same names and reference numerals and their descriptions may be omitted. The definition of direction is also the same as in the previously described embodiment unless otherwise specified. Also, the illustration of the weight 4 is omitted in Figures 7 to 10.

[0102] As shown in Figures 7 to 10, the cutting tool 10B with a dynamic balance adjustment mechanism of this embodiment has a flow path 2 comprising a first flow path 21 and a second flow path 22, with the second flow path 22 forming an annular shape extending over the entire circumference. Therefore, the second flow path 22 is connected to the entire circumferential area of ​​the first flow path 21.

[0103] Furthermore, the dynamic balance adjustment method for the cutting tool 10B in this embodiment comprises a balance adjustment step and a balance maintenance step, similar to the embodiment described above.

[0104] [Effects of this embodiment] According to the cutting tool 10B with a dynamic balance adjustment mechanism and the method for dynamically adjusting the balance of the cutting tool 10B of this embodiment described above, the same effects and advantages as those of the previously described embodiment can be obtained.

[0105] In this embodiment, the second channel 22 has an annular shape that extends over the entire circumference in the circumferential direction. In this case, the weight 4 is made movable within the second channel 22 over the entire circumference around the central axis O. This allows for a more stable expansion of the range over which balance can be adjusted.

[0106] <Third Embodiment> Next, a cutting tool 10C with a dynamic balance adjustment mechanism (rotating body 10 with a dynamic balance adjustment mechanism) and a method for dynamically adjusting the balance of the cutting tool 10C (method for dynamically adjusting the balance of the rotating body 10) according to a third embodiment of the present invention will be described with reference to Figures 11 to 14. In this embodiment, the same components as in the previously described embodiments may be given the same names and reference numerals, and their descriptions may be omitted. The definition of direction is also the same as in the previously described embodiments unless otherwise specified. In addition, the weight 4 is not shown in Figures 11 to 14.

[0107] As shown in Figures 11 to 14, in the cutting tool 10C with a dynamic balance adjustment mechanism of this embodiment, the shape of the tip portion of the tool body 1, including the axial tip (first end portion 1a), is a substantially polygonal columnar or substantially polygonal cylindrical shape centered on the central axis O. Specifically, the tip portion of the tool body 1 is a substantially square columnar or substantially square cylindrical shape extending in the axial direction.

[0108] As shown in Figure 14, in a view of the tool tip (bottom view) from the axial end of the tool, the tip portion of the tool body 1 has a roughly rectangular or oval shape, with a predetermined radial direction as the longitudinal direction and a direction perpendicular to this longitudinal direction as the short direction. Furthermore, as shown in Figure 11, the shape of the rear end portion of the tool body 1, including the axial rear end (second end 1b), is cylindrical or cylindrical with respect to the central axis O.

[0109] As shown in Figures 11 to 14, in this embodiment, multiple circumferentially extending flow channels 2 are provided on the tip portion of the tool body 1 at intervals from each other in the circumferential direction. Specifically, two flow channels 2 are provided at positions that are 180° rotationally symmetric with respect to the central axis O. In the view of the tool tip shown in Figure 14, the two flow channels 2 are arranged side by side in the longitudinal direction of the tool, with the central axis O located between the two flow channels 2.

[0110] Although not specifically shown in the diagrams, multiple cutting inserts are provided on the tool, and in this embodiment, two are provided. The two cutting inserts are positioned at both ends in the longitudinal direction of the tool. Specifically, each cutting insert is located at the end in the tool rotation direction T of the outer end (radial outer end) along the longitudinal direction of the tool. The flow path 2 is located in the part of the tool body 1 that supports the cutting insert from the opposite direction of tool rotation (the so-called back metal).

[0111] Furthermore, the circumferential dimensions of each channel 2 increase as they move radially outward. As shown in Figure 14, when the tool is viewed from the axial direction, the channel 2 has a roughly fan shape.

[0112] Furthermore, the dynamic balance adjustment method for the cutting tool 10C in this embodiment comprises a balance adjustment step and a balance maintenance step, similar to the embodiment described above.

[0113] [Effects of this embodiment] According to the cutting tool 10C with a dynamic balance adjustment mechanism and the method for dynamically adjusting the balance of the cutting tool 10C of this embodiment described above, the same effects and advantages as those of the previously described embodiment can be obtained.

[0114] In this embodiment, multiple flow paths 2 are provided at intervals from each other in the circumferential direction. In this case, the degree of freedom in arranging (layout) the flow path 2 is increased. Even if the shape of the tool body (main body) 1 of the cutting tool 10C (rotating body 10) is not cylindrical or cylindrical as in this embodiment, for example, a polygonal columnar shape or a polygonal cylindrical shape, the flow path 2 can be easily arranged to match the shape of the tool body 1.

[0115] Furthermore, in the above configuration, even if the central axis O of the cutting tool 10C (rotating body 10) is tilted with respect to the vertical or extends horizontally, problems such as the weight 4 being unevenly distributed in one place due to gravity within the tool body 1 are suppressed. In other words, because the weight 4 is distributed in each flow path 2 of the tool body 1, it is easier to stabilize and balance the rotation regardless of the orientation of the tool.

[0116] In this embodiment, the circumferential dimension of the flow path 2 increases as it moves radially outward. In this case, when the cutting tool 10C (rotating body 10) rotates and the weight 4 in the flow path 2 moves radially outward due to centrifugal force, a large degree of freedom (range in which the weight 4 can move freely in the circumferential direction) is ensured. This allows for a stable expansion of the range in which balance can be adjusted.

[0117] <Fourth Embodiment> Next, a cutting tool 10D with a dynamic balance adjustment mechanism (rotating body 10 with a dynamic balance adjustment mechanism) and a method for dynamically adjusting the balance of the cutting tool 10D (method for dynamically adjusting the balance of the rotating body 10) according to a fourth embodiment of the present invention will be described with reference to Figures 15 to 18. In this embodiment, the same configuration as in the previously described embodiment may be given the same names and reference numerals and their descriptions may be omitted. Also, the definition of direction is the same as in the previously described embodiment unless otherwise specified. Furthermore, the illustration of the weight 4 is omitted in Figures 15 to 18.

[0118] As shown in Figures 15 to 18, in the cutting tool 10D with a dynamic balance adjustment mechanism of this embodiment, the tool body 1 is cylindrical or cylindrical in shape, extending axially around the central axis O. Furthermore, the outer diameter of the tool body 1 is substantially constant along its entire length in the axial direction.

[0119] As shown in Figure 16, the cutting tool 10D (rotating body 10) has an axial dimension L that is larger than the outer diameter dimension (cutting diameter dimension) D of the tool. Multiple flow channels 2 are provided spaced apart from each other in the axial direction, and in this embodiment, two are provided. Each flow channel 2 forms an annular shape with a central axis O.

[0120] Furthermore, the dynamic balance adjustment method for the cutting tool 10D in this embodiment comprises a balance adjustment step and a balance maintenance step, similar to the embodiment described above.

[0121] [Effects of this embodiment] According to the cutting tool 10D with a dynamic balancing mechanism and the method for dynamically balancing the cutting tool 10D of this embodiment described above, the same effects and advantages as those of the previously described embodiment can be obtained.

[0122] In this embodiment, multiple flow paths 2 are provided, spaced apart from each other in the axial direction. With the above configuration, even when, for example, the axial dimension L of the tool body (body) 1 of the cutting tool 10D (rotating body 10) is larger than the outer diameter dimension D (i.e., when the tool body 1 has an elongated shape in the axial direction), the rotational balance of the tool can be stably balanced by the multiple flow channels 2 arranged at intervals from each other in the axial direction, and the dilatant fluid 3 and weights 4 arranged in each flow channel 2. In particular, when the above configuration is used for a cutting tool 10D with a large L / D ratio, it is possible to stably improve cutting accuracy and effectively extend tool life.

[0123] <Fifth Embodiment> Next, a cutting tool 10E with a dynamic balance adjustment mechanism (rotating body 10 with a dynamic balance adjustment mechanism) and a method for dynamically adjusting the balance of the cutting tool 10E (method for dynamically adjusting the balance of the rotating body 10) according to the fifth embodiment of the present invention will be described with reference to Figures 19 to 22. In this embodiment, the same components as in the previously described embodiments may be given the same names and reference numerals and their descriptions may be omitted. The definition of direction is also the same as in the previously described embodiments unless otherwise specified. Also, the weight 4 is not shown in Figures 19 to 22.

[0124] As shown in Figures 19 to 22, the cutting tool 10E with a dynamic balance adjustment mechanism of this embodiment has a tool body 1 which includes a plurality of insert mounting seats 12 arranged circumferentially at intervals from each other on the outer circumference of the tip of the tool body 1, to which each cutting insert (not shown) is detachably attached, and a plurality of chip pockets 13 which are recessed from the tip surface and outer circumference of the tool body 1 and are formed extending from the tool rotation direction T and the axial rear end of each insert mounting seat 12. The number of insert mounting seats 12 and the number of chip pockets 13 are the same as the number of cutting inserts, and in this embodiment, there are six of each.

[0125] The insert mounting seat 12 is positioned at the first end 1a (i.e., the tip) of the tool body 1 and opens to the tip surface and outer circumferential surface of the tool body 1. The insert mounting seat 12 is concave, recessed from the tip surface and outer circumferential surface of the tool body 1. The insert mounting seat 12 is formed to cut out the tip outer circumferential portion of the wall portion of the tip pocket 13 that faces the tool rotation direction T.

[0126] The shape of the insert mounting seat 12 corresponds to the shape of the cutting insert. In this embodiment, the cutting insert is in the shape of a rectangular plate, and the insert mounting seat 12 is in the shape of a rectangular hole.

[0127] In this embodiment, multiple insert mounting seats 12 are provided at equal pitches in the circumferential direction on the outer circumference of the tip of the tool body 1. Multiple cutting inserts of the same shape are mounted on the multiple insert mounting seats 12. Each cutting insert is detachably attached to each insert mounting seat 12 by clamp screws or the like.

[0128] The tip pocket 13 opens to the front end and outer circumference of the tool body 1. The tip pocket 13 is groove-shaped and extends from the front end of the tool body 1 toward the axial rear end. The tip pocket 13 is positioned adjacent to the insert mounting seat 12 on the tool rotation direction T and axial rear end side of the insert mounting seat 12.

[0129] In this embodiment, multiple tip pockets 13 are provided at equal pitches in the circumferential direction on the outer circumference of the tip of the tool body 1. The circumferential dimension of the tip pocket 13 is larger than the circumferential dimension of the insert mounting seat 12. Also, the axial dimension of the tip pocket 13 is larger than the axial dimension of the insert mounting seat 12.

[0130] In this embodiment, the flow path 2 includes a first flow path 21 extending in the circumferential direction, and a second flow path 22 connected to at least a portion of the first flow path 21 in the circumferential direction and extending from the first flow path 21 in at least one of the axial and radial directions. Specifically, the first flow path 21 is an annular shape extending over the entire circumference in the circumferential direction. The second flow path 22 is connected to the rear end portion (upper portion) of the first flow path 21. Multiple second flow paths 22 are provided spaced apart from each other in the circumferential direction, and in this embodiment, three are provided at equal pitches in the circumferential direction.

[0131] More specifically, as shown in Figure 21, in this embodiment, the second flow path 22 extends (spreads out) from the connection point with the first flow path 21 toward the axial rear end (upward) and radially inward. As shown in Figure 22, the circumferential dimension of the second flow path 22 decreases as it moves radially inward.

[0132] In Figure 21, the flow path 2 has a bottom portion 21a located at the lowest part of the flow path 2, and an inclined surface 22a positioned above the bottom portion 21a and extending upward radially from the bottom portion 21a. In this embodiment, the bottom portion 21a is located in the first flow path 21, and the inclined surface 22a is located in the second flow path 22. The inclined surface 22a extends upward radially inward from the bottom portion 21a. Therefore, the inclined surface 22a faces radially outward and upward.

[0133] Furthermore, the dynamic balance adjustment method for the cutting tool 10E in this embodiment comprises a balance adjustment step and a balance maintenance step, similar to the embodiment described above.

[0134] [Effects of this embodiment] According to the cutting tool 10E with a dynamic balancing mechanism and the method for dynamically balancing the cutting tool 10E of this embodiment described above, the same effects and advantages as those of the previously described embodiment can be obtained.

[0135] [Other components included in the present invention] The present invention is not limited to the embodiments described above, and modifications to the configuration, etc., are possible without departing from the spirit of the invention, as described below, for example.

[0136] In the embodiments described above, the cutting tools 10A to 10E were described as replaceable tip cutters or replaceable tip end mills, but are not limited to these. The cutting tools may also be, for example, replaceable tip drills or replaceable tip reamers. Furthermore, the cutting tools are not limited to replaceable tip types in which cutting inserts having cutting edges are detachably attached to the tool body, but may also be solid types (integrated type) in which the cutting edges are integrally formed with the tool body.

[0137] Although not specifically shown in the diagram, the tool body 1 may also have coolant holes extending inside the tool body 1. The coolant holes open into each chip pocket, etc., toward the vicinity of each cutting edge of the multiple cutting inserts.

[0138] In the embodiment described above, an example was given in which the flow path 2 is located inside the tool body 1, but the invention is not limited to this. For example, the flow path may be composed of a pipe extending in the circumferential direction and fixed to the outer circumference of the tool body by welding, screwing, or the like. In other words, the flow path may be provided externally to the tool body.

[0139] In the embodiments described above, examples were given in which the weight 4 is spherical or granular, but it is not limited to these. Although not specifically shown, the weight may be columnar, needle-shaped, or the like.

[0140] Furthermore, in the dynamic balancing method for the cutting tools 10A to 10E described above (dynamic balancing method for the rotating body 10), the tool body (main body) 1 may be rotated alternately in forward and reverse directions around the central axis O, on one side in the circumferential direction (tool rotation direction T) and on the other side in the circumferential direction (opposite tool rotation direction). In this case, the rotational balance of the cutting tools 10A to 10E (rotating body 10) can be balanced with higher precision during the balancing process.

[0141] Furthermore, in the embodiments described above, the tool rotation direction T is set to counterclockwise when the tool is viewed from the axial end, as shown in Figure 4, but this is not limited to this. The tool rotation direction T may also be clockwise when the tool is viewed from the axial end. In other words, the present invention is applicable to cutting tools with different characteristics than those in the embodiments described above.

[0142] Furthermore, the present invention is applicable to rotating bodies other than cutting tools described in the embodiments above. Examples of such rotating bodies include chucks and spindles of machine tools. The present invention may also be applied to rotating bodies other than machine tools.

[0143] The present invention may be combined in any way that does not depart from the spirit of the invention, as described in the above embodiments and modifications, and the configurations may be added, omitted, substituted, or otherwise modified. Furthermore, the present invention is not limited by the above embodiments, but is limited only by the claims. [Industrial applicability]

[0144] According to the present invention, a rotating body with a dynamic balancing mechanism, a method for dynamically balancing a rotating body, a cutting tool with a dynamic balancing mechanism, and a method for dynamically balancing a cutting tool are provided, all of which have a simple structure, a small number of parts, are easy to manufacture, have fewer shape limitations, are easily miniaturized, and have a wide range of balance adjustment. Therefore, they have industrial applicability. [Explanation of Symbols]

[0145] 1…Tool body (main unit) 2…flow channel 3… Dilatant fluids 4... Weight 10…Rotational body 10A,10B,10C,10D,10E…Cutting tools 21...First channel 21a...bottom 22...Second channel 22a…Slope surface O…Central axis

Claims

1. The main body can be rotated around its central axis, The main body is provided with a flow path that extends in the circumferential direction, The dilatant fluid that fills the aforementioned channel, A weight housed in the aforementioned flow path, The aforementioned weight is If the magnitude of the acceleration acting on the dilatant fluid due to the rotation of the main body is less than a predetermined value, it is made possible to move within the liquid dilatant fluid. When the magnitude of the acceleration exceeds a predetermined value, the solidified dilatant fluid is held in place. A rotating body with a dynamic balancing mechanism.

2. The aforementioned flow path has an annular first flow path that extends over the entire circumference in the circumferential direction. A rotating body with a dynamic balance adjustment mechanism as described in claim 1.

3. The aforementioned flow path is A first channel extending in the circumferential direction, A second flow channel is connected to at least a portion of the first flow channel in the circumferential direction and extends from the first flow channel in at least one of the axial and radial directions, A rotating body with a dynamic balance adjustment mechanism according to claim 1 or 2.

4. The second flow channels are provided in multiple locations, spaced apart from each other in the circumferential direction. A rotating body with a dynamic balance adjustment mechanism as described in claim 3.

5. The aforementioned flow path is The bottom located at the lowest part of the aforementioned flow path, It has an inclined surface positioned above the bottom and extending upward radially from the bottom, A rotating body with a dynamic balance adjustment mechanism according to claim 1 or 2.

6. Multiple channels are provided in the circumferential direction, spaced apart from each other. A rotating body with a dynamic balance adjustment mechanism according to claim 1 or 2.

7. The circumferential dimension of the flow path increases as it moves radially outward. A rotating body with a dynamic balance adjustment mechanism according to claim 1 or 2.

8. Multiple flow channels are provided at intervals from each other in the axial direction. A rotating body with a dynamic balance adjustment mechanism according to claim 1 or 2.

9. The weight is spherical or particulate. A rotating body with a dynamic balance adjustment mechanism according to claim 1 or 2.

10. A method for adjusting the dynamic balance of a rotating body using a rotating body with a dynamic balance adjustment mechanism as described in claim 1 or 2, A balancing step involves rotating the main body around the central axis while keeping the magnitude of the acceleration below a predetermined value, and moving the weight so that the rotational balance is equilibrium within the liquid dilatant fluid. The system includes a balancing step in which the main body is rotated around the central axis while the magnitude of the acceleration is set to a predetermined value or greater, and the weight is held by the solidified dilatant fluid. A method for dynamically balancing a rotating body.

11. In the balance adjustment process, the main body is rotated alternately in forward and reverse directions around the central axis, A method for dynamically balancing a rotating body according to claim 10.

12. A tool body that can be rotated around a central axis, The tool body is provided with a flow path that extends in the circumferential direction, The dilatant fluid that fills the aforementioned channel, A weight housed in the aforementioned flow path, The aforementioned weight is If the magnitude of the acceleration acting on the dilatant fluid due to the rotation of the tool body is less than a predetermined value, the tool body can move within the liquid dilatant fluid. When the magnitude of the acceleration exceeds a predetermined value, the solidified dilatant fluid is held in place. Cutting tool with dynamic balancing mechanism.

13. A method for adjusting the dynamic balance of a cutting tool using a cutting tool with a dynamic balance adjustment mechanism as described in claim 12, A balancing step involves rotating the tool body around the central axis while keeping the magnitude of the acceleration below a predetermined value, and moving the weight so that the rotational balance is equilibrium within the liquid dilatant fluid. The system includes a balancing step in which the tool body is rotated around the central axis while the magnitude of the acceleration is set to a predetermined value or greater, and the weight is held by the solidified dilatant fluid. A method for dynamically balancing cutting tools.

Images