JP6273120B2 - Cutting tools and cutting equipment - Google Patents

Description

  The present invention relates to a cutting tool and a cutting apparatus for cutting an inner diameter surface of a workpiece.

  When cutting the inner diameter surface of the workpiece, it is important to suppress damage to the cutting surface due to chips. For this reason, it is considered that a cutting tool (boring bar or the like) is formed thin to widen a gap between the workpiece and the cutting tool and secure a chip discharge path. However, forming the cutting tool thinly reduces the rigidity of the cutting tool, and therefore causes a reduction in processing accuracy and processing speed during cutting. In view of this, there has been proposed a cutting tool that discharges chips together with the cutting fluid by spraying the cutting fluid from the tip of the cutting tool (see Patent Documents 1 and 2).

Registered Utility Model No. 3139545 JP 2007-75933 A

  However, the cutting tools described in Patent Documents 1 and 2 have a structure in which chips are pushed away by a cutting fluid that overflows from a cutting hole of a workpiece. Thus, since the cutting fluid overflowing from the workpiece is used, it is difficult to ensure the momentum of the cutting fluid, and it has been difficult to improve the chip discharge performance. In order to suppress cutting surface damage and improve cutting quality, it is necessary to stably discharge a large amount of chips. Therefore, it is required to improve chip discharging performance by cutting tools and cutting devices. Yes.

  An object of the present invention is to improve chip discharge performance.

The cutting tool of the present invention is a cutting tool that is attached to a cutting device and cuts the inner surface of a workpiece, and includes a first shaft portion on the base end side that is detachable from the cutting device, and a blade that cuts the workpiece A tool main body including a second shaft portion on a distal end side on which a portion is provided, a first port for injecting cutting fluid on the proximal end side, and a cutting fluid on the distal end side. A second port is formed , and the first port is formed on the tip side of the second port, and the center line of the first port and the center line of the second port do not contact each other.

The cutting device of the present invention is a cutting device that cuts the inner diameter surface of a workpiece using a cutting tool, and the cutting tool includes a first shaft portion on a base end side that is detachably attached to the cutting device, and the workpiece. A tool body provided with a second shaft portion on the distal end side provided with a blade portion for cutting the first portion, a first port for injecting cutting fluid on the proximal end side, and cutting on the distal end side in the tool body. A second port for injecting liquid is formed. In the tool body, the center line of the first port and the center line of the second port are not in contact with each other, and the first port is more than the second port. Is also formed on the distal end side, and the cutting device supplies a cutting fluid supply that operates in a first state in which the cutting fluid is supplied to the first port and a second state in which the supply of the cutting fluid to the first port is stopped. And the cutting fluid supply unit cuts the workpiece. To be alternately switched on and the second state and the first state.

  According to the present invention, since the first port for injecting the cutting fluid is formed on the base end side, it becomes possible to push the chips together with the cutting fluid to the base end side. Thereby, it becomes possible to improve the discharge performance of chips.

It is the schematic which shows the cutting device which is one embodiment of this invention. (A) is a top view which shows a boring bar, (b) is a front view which shows a boring bar, (c) is a left view which shows a boring bar. It is explanatory drawing which shows the cutting condition of the workpiece | work by a boring bar. (A)-(c) is explanatory drawing which shows the injection condition of the coolant by a boring bar. It is a timing chart which shows an example of the supply condition of coolant. (A)-(c) is explanatory drawing which shows the cutting tool which is other embodiment of this invention. It is the schematic which shows the cutting device which is other embodiment of this invention. (A) And (b) is a fragmentary sectional view which shows the cutting tool which is other embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic view showing a cutting apparatus 10 according to an embodiment of the present invention. As shown in FIG. 1, the cutting apparatus 10 has a main shaft 11 that is rotationally driven, and a chuck 12 that fixes a workpiece W is provided on the main shaft 11. Further, the cutting apparatus 10 has a turret 14 including a plurality of tool holders 13. A boring bar (cutting tool) 15 according to an embodiment of the present invention is attached to the tool holder 13 of the turret 14. When cutting the workpiece W, the turret 14 is indexed and rotated to place the boring bar 15 at a predetermined position, and the boring bar 15 is inserted into the rotating workpiece W. As a result, the inner diameter surface Wa of the workpiece W is cut by the boring bar 15, and a hole having a predetermined dimension can be machined in the workpiece W.

  2A is a plan view showing the boring bar 15, FIG. 2B is a front view showing the boring bar 15, and FIG. 2C is a left side view showing the boring bar 15. As shown in FIGS. 2A to 2C, the boring bar 15 has a tool body 20 formed integrally. The tool body 20 includes a proximal-side mounting shaft (first shaft portion) 21 that is detachable from the tool holder 13 and a distal-end shank (second shaft portion) that is integrally provided on the mounting shaft 21 via a flange 22. 23). A notch 24 is formed at the tip of the shank 23, and a vertical surface 25 and an inclined surface 26 connected thereto are formed in the notch 24. The vertical surface 25 is substantially parallel to the axial direction of the shank 23, and the inclined surface 26 is inclined with respect to the axial direction of the shank 23. The inclined surface 26 of the notch 24 is configured as a curved surface. Further, the shank 23 is formed with a spiral groove 27 that is connected to the notch 24 and extends in a spiral manner on the outer peripheral surface. A flute groove (chip discharge groove) 28 extending from the distal end side to the proximal end side is constituted by the cutout portion 24 of the shank 23 and the spiral groove 27 communicating with the cutout portion 24. A concave mounting seat 29 is formed on the vertical surface 25 of the notch 24, and an insert (blade portion) 30 called a tip is fixed to the mounting seat 29 by a clamp screw 31.

  A first port 41 that opens toward the base end side is formed near the boundary between the vertical surface 25 and the inclined surface 26 in the notch 24. The first port 41 is a port that opens toward the spiral groove 27 closer to the base end side than the first port 41. In addition, a second port 42 that opens toward the distal end side is formed on the inclined surface 26 of the notch 24. The second port 42 is a port that opens toward the insert 30 on the tip side of the second port 42. Further, the first port 41 and the second port 42 are formed with respect to the notch 24 of the shank 23 so that the respective center lines do not cross each other, that is, so that the respective center lines do not contact each other. Yes. As shown in FIG. 2B, a first flow path 43 and a second flow path 44 extending from the mounting shaft 21 to the shank 23 are formed inside the tool body 20. The first flow path 43 communicates with the first port 41, and the second flow path 44 communicates with the second port 42.

  Next, the coolant supply path to the boring bar 15 will be described. The coolant is a cutting fluid having a lubrication function, a cooling function, and the like with respect to a cutting location. As shown in FIG. 1, the cutting device 10 includes a tank 45 in which a coolant (cutting fluid) C is stored and a pump 46 installed in the tank 45. Moreover, the cutting device 10 has a valve unit (cutting fluid supply unit) 47 constituted by a plurality of electromagnetic switching valves 49b, 50b, 51b and the like. The valve unit 47 has an input flow path 48 connected to the discharge port of the pump 46. A first supply path 49, a second supply path 50, and a third supply path 51 are connected to the input flow path 48. Each of the supply paths 49 to 51 includes check valves 49a, 50a, 51a, electromagnetic switching valves 49b, 50b, 51b, and throttle valves 49c, 50c, 51c. The output flow path 52 connected to the first supply path 49 is connected to the first flow path 43 of the boring bar 15 via a connection flow path 53 formed in the turret 14 and the tool holder 13. Similarly, the output flow path 54 connected to the second supply path 50 is connected to the second flow path 44 of the boring bar 15 via the connection flow path 55 formed in the turret 14 and the tool holder 13. Yes. Furthermore, the output flow path 56 connected to the third supply path 51 is connected to an injection nozzle 57 that injects coolant.

  In order to control the operation state of the electromagnetic switching valves 49b, 50b, 51b of the valve unit 47, the cutting apparatus 10 is provided with a control unit 60 including a CPU, a memory, a drive circuit, and the like. The control unit 60 controls the electromagnetic switching valves 49b, 50b, 51b in a communication state or a cutoff state in accordance with a predetermined control program. When the electromagnetic switching valve 49 b of the first supply path 49 is switched to the communication state, the coolant discharged from the pump 46 passes through the first supply path 49, the output flow path 52, and the connection flow path 53, and the first of the boring bar 15. 1 channel 43 is supplied. And the coolant supplied to the 1st flow path 43 of the boring bar 15 is injected toward the spiral groove 27 of the base end side from the 1st port 41 mentioned above. On the other hand, when the electromagnetic switching valve 49b of the first supply path 49 is switched to the shut-off state, the coolant is shut off in the first supply path 49, so that the coolant supply from the first port 41 to the spiral groove 27 is shut off. As described above, when the valve unit 47 is controlled to the first state communicating with the first supply path 49, the coolant is injected from the first port 41. On the other hand, when the valve unit 47 is controlled to the second state in which the first supply path 49 is blocked, the injection of the coolant from the first port 41 is stopped.

  Further, when the electromagnetic switching valve 50b of the second supply path 50 is switched to the communication state, the coolant discharged from the pump 46 passes through the second supply path 50, the output flow path 54, and the connection flow path 55, and then the boring bar 15 To the second flow path 44. And the coolant supplied to the 2nd flow path 44 of the boring bar 15 is injected toward the insert 30 of the front end side from the 2nd port 42 mentioned above. On the other hand, when the electromagnetic switching valve 50b of the second supply path 50 is switched to the shut-off state, the coolant is shut off in the second supply path 50, so that the coolant supply from the second port 42 to the insert 30 is shut off. Note that when the electromagnetic switching valve 51 b of the third supply path 51 is switched to the communication state, the coolant discharged from the pump 46 is supplied to the injection nozzle 57 via the third supply path 51 and the output flow path 56. The coolant supplied to the injection nozzle 57 is injected toward the workpiece W and the boring bar 15.

  Next, the cutting state of the workpiece W by the boring bar 15 will be described. FIG. 3 is an explanatory view showing a cutting state of the workpiece W by the boring bar 15. FIGS. 4A to 4C are explanatory views showing the state of coolant injection by the boring bar 15. 4A shows a plan view of the notch 24 of the shank 23 that is enlarged, and FIG. 4B shows a front view of the notch 24 of the shank 23 that is enlarged. FIG. ) Shows a left side view in which the notch 24 of the shank 23 is enlarged.

  As shown in FIG. 3, when the workpiece W is cut by the boring bar 15, the boring bar 15 is positioned in the radial direction (arrow A direction), and the boring bar 15 is advanced in the axial direction (arrow B direction). Thus, by advancing the boring bar 15 toward the rotating workpiece W, the inner diameter surface Wa of the workpiece W is cut by the insert 30, and a hole having a predetermined dimension is machined in the workpiece W. At this time, as indicated by an arrow α in the enlarged portion of FIG. 3, the chips Wb generated from the workpiece W travel from the insert 30 toward the inclined surface 26 and are discharged to the outside of the workpiece W along the spiral groove 27. . Thus, since the clearance gap is ensured between the workpiece | work W and the shank 23 by the flute groove | channel 28 provided with the notch part 24 and the spiral groove 27, the discharge | emission performance which discharges | emits the chip Wb out of the workpiece | work W is improved. Is possible.

  Next, as shown by the white arrow α in FIGS. 4A to 4C, when cutting the workpiece W, coolant is injected from the second port 42 toward the insert 30. Thereby, since a coolant can be supplied toward the contact location of the workpiece | work W and the insert 30, it becomes possible to improve cutting quality and cutting speed. That is, the coolant sprayed from the second port 42 functions as a coolant for cutting for favorably cutting the workpiece W. Further, as shown by the black arrow β in FIGS. 4A to 4C, when cutting the workpiece W, coolant is injected from the first port 41 toward the flute groove 28. As a result, the coolant flows in the flute groove 28 through which the chips Wb are guided, so that the chips Wb can be pushed away by the coolant, and the discharge performance of the chips Wb can be improved. That is, the coolant injected from the first port 41 functions as a coolant for discharge for discharging the chips Wb satisfactorily. In this way, the chip Wb is discharged out of the workpiece W by the discharge coolant, so that it is possible to suppress damage to the cutting surface due to the chip Wb and to improve the cutting quality.

  Moreover, as shown to Fig.4 (a)-(c), the 1st port 41 and the 2nd port 42 are formed so that each centerline may not mutually contact. As a result, the coolant injected from the first port 41 and the coolant injected from the second port 42 can reach the insert 30 and the flute groove 28 without greatly interfering with each other. The center line of the first port 41 is a line that coincides with the arrow β shown as the injection direction in FIG. Similarly, the center line of the second port 42 is a line coinciding with the arrow α shown as the injection direction in FIG.

  Next, the supply status of the coolant when cutting the workpiece W will be described. FIG. 5 is a timing chart showing an example of a coolant supply state. As shown in FIG. 5, when the boring bar 15 is advanced toward the workpiece W, before the cutting starts, that is, before the insert 30 contacts the workpiece W, injection of cutting coolant from the second port 42 toward the insert 30 is performed. Be started. Next, when the workpiece W and the insert 30 come into contact with each other and cutting is started, injection of the coolant for discharge from the first port 41 toward the flute groove 28 is started. When injecting the coolant for discharge, the valve unit 47 is alternately switched between the first state and the second state, and the injection and stop of the coolant for discharge are repeated. Thereby, the coolant for discharge can be pulsated and injected, and the discharge performance of the chips Wb can be improved. Then, after the end of cutting, that is, after the insert 30 is separated from the workpiece W, the coolant for cutting continuously injected from the second port 42 is stopped, and the coolant for discharging intermittently injected from the first port 41 is stopped. Is stopped. The injection start timing and the injection end timing of the discharged coolant are adjusted according to the discharge state of the chips Wb.

  As described above, since the first port 41 for injecting the coolant is provided on the base end side with respect to the tool main body 20 of the boring bar 15, the chips Wb can be pushed to the base end side together with the coolant. . In particular, the coolant injected from the first port 41 pushes away the chips Wb while maintaining the flow rate without interfering with others, so that a large amount of chips Wb can be discharged stably. Thus, since the chips Wb can be discharged well by the coolant, it is possible to suppress damage to the cutting surface by the chips Wb, and it is possible to improve the cutting quality. Further, since the chip Wb discharge performance in the boring bar 15 is enhanced, the flute groove 28 provided for chip discharge can be reduced or reduced. Thereby, since the rigidity of the boring bar 15 can be increased, cutting quality and cutting speed can be increased.

  In the above description, the first flow path 43 and the second flow path 44 are formed with respect to the tool body 20 of the boring bar 15, but the present invention is not limited to this, and the first port 41 and the second port 42 may be formed in the tool body. Here, FIGS. 6A to 6C are explanatory views showing a boring bar (cutting tool) 70 according to another embodiment of the present invention. FIG. 6A shows a plan view of the notch 24 of the shank 23 that is enlarged, and FIG. 6B shows a front view of the notch 24 of the shank 23 that is enlarged. ) Shows a left side view in which the notch 24 of the shank 23 is enlarged. FIG. 7 is a schematic view showing a cutting device 71 according to another embodiment of the present invention. In FIG. 6, members and parts similar to those shown in FIG. 4 are denoted by the same reference numerals and description thereof is omitted. In FIG. 7, the same members and parts as those shown in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIGS. 6A to 6C, one flow path 73 extending from the attachment shaft 21 to the shank 23 is formed in the tool main body 72 included in the boring bar 70. The flow path 73 communicates with the first port 41 via the branch flow path 74 and also communicates with the second port 42 via the branch flow path 75. As shown in FIG. 7, the valve unit (cutting fluid supply unit) 76 constituting the cutting device 71 is provided with a supply path 77 including a check valve 77a, an electromagnetic switching valve 77b, and a throttle valve 77c. Yes. The output flow path 78 connected to the supply path 77 is connected to the flow path 73 of the boring bar 70 via a connection flow path 79 formed in the turret 14 and the tool holder 13.

  Thus, when the flow path 73 communicating with both the first port 41 and the second port 42 is formed in the tool body 72, the electromagnetic switching valve 77b of the valve unit 76 is controlled to be in a communicating state, The coolant is injected from both the first port 41 and the second port 42. Even when such a boring bar 70 is used, since the coolant can be injected from the first port 41 toward the base end side, the same effect as the boring bar 15 described above can be obtained.

  In the boring bar 70 shown in FIG. 6, the first port 41 and the flow path 73 are directly communicated with each other. However, the present invention is not limited to this, and the first port 41 and the flow path 73 are not connected. An on-off valve may be provided. Here, FIGS. 8A and 8B are partial sectional views showing a boring bar (cutting tool) 80 according to another embodiment of the present invention. FIGS. 8A and 8B are partial cross-sectional views enlarging the notch 24 of the shank 23. FIG. In FIG. 8, members and parts similar to those shown in FIG. 6 are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 8A, an open / close valve 81 that is opened and closed based on the pressure of the coolant is provided between the flow path 73 and the branch flow path 74. A valve accommodation hole 82 communicating with both the flow path 73 and the branch flow path 74 is formed at the tip of the shank 23. A valve body 83 is movably accommodated in the valve accommodation hole 82, and a plug 84 is assembled to the opening of the valve accommodation hole 82. A spring 85 is incorporated between the plug 84 and the valve body 83, and the spring 85 biases the valve body 83 in the direction of arrow A. When the pressure of the coolant in the flow path 73 is low, as shown in FIG. 7A, the on-off valve 81 is cut off, that is, the valve body 83 is urged in the direction of arrow A by the spring 85. The channel 83 and the branch channel 74 are blocked by the body 83. On the other hand, when the pressure of the coolant in the flow path 73 is high, as shown in FIG. 7B, the on-off valve 81 is in communication, that is, the valve element 83 is pushed in the direction of the arrow B against the spring 85. Thus, the flow path 73 and the branch flow path 74 communicate with each other. That is, when the low pressure coolant is supplied to the boring bar 15, the first port 41 is shut off by the on-off valve 81, so that the coolant is injected only from the second port 42. On the other hand, when high-pressure coolant is supplied to the boring bar 15, the first port 41 is opened by the on-off valve 81, so that coolant is injected from both the first port 41 and the second port 42.

  When such a boring bar 80 is used, the electromagnetic switching valve 77b constituting the supply path 77 shown in FIG. 6 is changed to a pressure control valve or a flow control valve capable of adjusting the pressure in the flow path 73. It is desirable. That is, when the valve unit 76 is controlled to the first state in which the high-pressure coolant is output from the supply path 77, the coolant can be injected from the first port 41. On the other hand, when the valve unit 76 is controlled to the second state in which the low-pressure coolant is output from the supply path 77, the coolant injection from the first port 41 can be stopped. That is, by switching the valve unit 47 between the first state and the second state and increasing or decreasing the pressure of the coolant output from the supply path 77, the coolant for discharge can be pulsated and injected, and the waste Wb is discharged. The performance can be improved.

  It goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, in the above description, the cutting devices 10 and 71 that rotate the workpiece W are used. However, the present invention is not limited to this, and a cutting device that rotates a cutting tool may be used. In the above description, the boring bar 15 to which the insert 30 can be attached and detached is cited as a cutting tool. However, the boring bar 15 is not limited to this, and may be a boring bar provided with an integrally fixed blade portion. In the above description, the boring bar is used as the cutting tool. However, the boring bar is not limited to this, and a cutting tool such as a drill for drilling holes may be used.

  In the above description, the two ports 41, 42 are formed for the boring bars 15, 70, 80. However, the present invention is not limited to this, and three or more ports may be formed. In the above description, the spiral flute grooves 28 are formed in the boring bars 15, 70, 80. However, the present invention is not limited to this, and the straight flute grooves are formed in the boring bars 15, 70, 80. The flute grooves may be reduced from the boring bars 15, 70, 80. In the above description, the coolant for discharging is intermittently injected from the first port 41, but the present invention is not limited to this, and the coolant for discharging may be continuously injected from the first port 41. . In the above description, the cutting coolant is continuously injected from the second port 42, but the present invention is not limited to this, and the cutting coolant may be intermittently injected from the second port 42. . In the above description, the coolant is supplied from the valve units 47, 76 to the boring bars 15, 70, 80. However, both the coolant and the compressed air may be supplied to the boring bars 15, 70, 80. .

10 Cutting device 15 Boring bar (cutting tool)
20 Tool body 21 Mounting shaft (first shaft)
23 Shank (second shaft part)
28 Flute groove (chip discharge groove)
30 Insert (blade)
41 1st port 42 2nd port 43 1st flow path 44 2nd flow path 47 Valve unit (cutting fluid supply part)
70 Boring bar (cutting tool)
71 Cutting device 72 Tool body 73 Flow path 76 Valve unit (Cutting fluid supply unit)
80 Boring bar (cutting tool)
81 On-off valve W Work Wa Inner surface C Coolant (Cutting fluid)

Claims (7)

A cutting tool attached to a cutting device for cutting an inner diameter surface of a workpiece,
A tool body comprising: a first shaft portion on the base end side that is detachably attached to the cutting device; and a second shaft portion on the tip end side provided with a blade portion for cutting the workpiece.
Have
The tool body is formed with a first port for injecting the cutting fluid to the proximal end side and a second port for injecting the cutting fluid to the distal end side ,
The first port is formed on the tip side of the second port, and the center line of the first port and the center line of the second port are not in contact with each other . In the cutting tool according to claim 1 Symbol placement,
In the tool body, a chip discharge groove extending from the distal end side to the proximal end side is formed,
The first port is a cutting tool that opens toward the chip discharge groove. The cutting tool according to claim 1 or 2 ,
The said 2nd port is a cutting tool opened toward the said blade part. In the cutting tool according to any one of claims 1 to 3 ,
A cutting tool in which a first flow path communicating with the first port and a second flow path communicating with the second port are formed in the tool body. In the cutting tool according to any one of claims 1 to 3 ,
A cutting tool in which a flow path communicating with both the first port and the second port is formed in the tool body. The cutting tool according to claim 5 , wherein
A cutting tool, wherein an opening / closing valve that is opened and closed based on a pressure of a cutting fluid is provided between the first port and the flow path. A cutting device for cutting an inner diameter surface of a workpiece using a cutting tool,
The cutting tool is
A tool body provided with a first shaft portion on the base end side that is detachable from the cutting device, and a second shaft portion on the tip end side on which a blade portion for cutting the workpiece is provided;
The tool body is formed with a first port for injecting the cutting fluid to the proximal end side and a second port for injecting the cutting fluid to the distal end side,
In the tool body, the center line of the first port and the center line of the second port are not in contact with each other, and the first port is formed on the tip side of the second port,
The cutting device is
A cutting fluid supply section that operates in a first state in which the cutting fluid is supplied to the first port and a second state in which the supply of the cutting fluid to the first port is stopped;
The cutting device, wherein the cutting fluid supply unit is alternately switched between the first state and the second state when cutting the workpiece.

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