DISPLAY DEVICE

Abstract

A display device (20) that obtains and displays information about a machine tool (10), the machine tool comprising a spindle (M0) for relatively rotating a workpiece (W), a cutting tool (14) and at least one feed axis (M1, M2) for relatively advancing the workpiece (W) and the cutting tool (14), and performing the machining of the workpiece (W) while the cutting tool (14) and the workpiece (W) are oscillated relative to each other, the display device (20) comprising: a first information display unit (31) that displays first information indicating a position to which the cutting tool (14) is advanced relative to the workpiece (W); a second information display unit (32) that displays second information indicating a relationship between a phase of the spindle (M0) and a position of the feed axis (M1, M2) so that it can be recognized whether the tool paths overlap due to the relative vibration between the cutting tool (14) and the workpiece (W); and an area selection unit (23) which selects a part of the first information as a selection area, wherein the second information display unit (32) changes the display area of ​​the second information such that the display area corresponds to the selection area selected by the area selection unit (23).

Description

BACKGROUND OF THE INVENTIONField of the invention

[0001] The present invention relates to a display device of a machine tool that performs cutting of a workpiece by a coordinated operation of a spindle and a feed axis, and more particularly, to a display device that displays a path of the feed axis of a machine tool that performs swing cutting. Related prior art

[0002] When a workpiece is machined with a cutting tool of a machine tool, if wood chips are continuously generated, the wood chips may become entangled in the cutting tool. In this case, it is necessary to stop the machine tool to remove the wood chips from the cutting tool, which takes a long time and reduces production efficiency. Furthermore, the wood chips may damage the workpiece, thus reducing the quality of the workpiece. To prevent such a defect, swing cutting is known. In this case, the cutting tool and the workpiece are caused to swing relatively in the machining direction, thereby crushing the wood chips (see, for example, Patent Document 1 and Patent Document 2).The controller of the machine tool performing oscillating cutting provides a sinusoidal feed command to a servomotor for a feed axis, which feeds the cutting tool or the workpiece in the machining direction, thereby causing the cutting tool and the workpiece to oscillate relatively in the machining direction. Conventionally, a waveform display device is known that displays, as waveforms, command data calculated with a numerical control system (CNC) according to a machining program and commanded to the servomotors of each axis of the machine tool, actual position data output from the position detection devices included in each axis, and the like (for example, Patent Document 3).

[0003] DE 10 2010 017 763 B4 relates to a tool path display device comprising a data acquisition device that simultaneously acquires and stores position information, speed information, acceleration information, position deviation information and a torque command from the respective drive axes at each time point as time series data, and a tool path calculation device.

[0004] WO 2015 146 945 A1 relates to a control device for a machine tool provided in a machine tool having a cutting tool for cutting a workpiece, a rotating device for relatively rotating the cutting tool and the workpiece, a feeding device for feeding the cutting tool and the workpiece in a predetermined feeding direction, and a vibrating device for relatively reciprocating the cutting tool and the workpiece along the feeding direction.

[0003] Patent document 1: JP 5 033 929 B1 Patent document 2: JP 5 599 523 B1 Patent document 3: JP 6 001 720 B1 SUMMARY OF THE INVENTION

[0005] In order to achieve the desired chipping during the oscillating cutting operation described above, it is necessary to previously determine the frequency, amplitude, and the like of the feed command to use the feed axis to periodically oscillate the cutting tool or workpiece in the machining direction of the workpiece. In the numerical control system of the machine tool, an NC program that can set machining conditions such as the spindle revolutions and feed rate, and other various parameters, is generated and stored, and the feed command for the oscillating operation described above is calculated according to the NC program. Therefore, an operator changes the machining conditions and various parameters set in the NC program in the numerical control system to determine the frequency, amplitude, and the like of the feed command for the oscillating operation.In the operation described above, it is easier to verify how the command data and actual position data for the feed axis that performs the oscillating operation change according to the change in machining conditions and various types of parameters set in the NC program in the numerical control system. The waveform display device described above is useful. However, it is disadvantageously difficult to determine whether or not the wood chips can be crushed with the cutting tool simply by displaying a waveform that changes the command data or actual position data on the feed axis that performs the oscillating operation over time.

[0006] An object of the present invention is to provide a display device with which an operator can visually and easily determine whether or not wood chips can be shredded by oscillating cutting.

[0007] A display device (for example, a display device 20, which will be described later) according to the present invention obtains and displays information about a machine tool (for example, a machine tool 10, which will be described later) that includes a spindle (for example, a spindle M0, which will be described later) for relatively rotating a workpiece (for example, a workpiece W, which will be described later) and a cutting tool (for example, a cutting tool 14, which will be described later) and at least one feed axis (for example, a feed axis M1, M2, which will be described later) for relatively feeding the workpiece and the cutting tool, and that performs machining of the workpiece while relatively vibrating the cutting tool and the workpiece, and that includes: a first information display unit (for example, a first information display unit 31,which will be described later) that displays first information indicating a position to which the cutting tool is fed relative to the workpiece; a second information display unit (for example, a second information display unit 32, which will be described later) that displays second information indicating a relationship between the phase of the spindle and the position of the feed axis; and an area selection unit (for example, an area selection unit 23, which will be described later) that selects a part of the first information as a selection area, and the second information display unit changes the display area of ​​the second information such that the display area corresponds to the selection area selected by the area selection unit.

[0008] (2) The display device described in (1) may further include an area switching unit (for example, an area switching unit 25 described later) that changes the display area of ​​the second information, and the area selecting unit may change the selection area so that the selection area corresponds to the display area of ​​the second information changed by the area switching unit.

[0009] (3) The display device described in (1) may further include a third information display unit (for example, a third information display unit 33 described later) that displays third information indicating a temporal change of the position information, the torque information, the speed information, and the acceleration information of the feed axis (M1, M2), the third information display unit may further display the third information, or the second information display unit and the third information display unit may exchange the second information with the third information to display the third information, and the third information display unit may change the display range of the third information so that the display range corresponds to the selection range selected by the range selection unit.

[0010] (4) The display device described in (3) may further include an area switching unit (for example, an area switching unit 25 described later) that changes at least one of the display area of ​​the second information and the display area of ​​the third information, and the area selecting unit may change the selection area so that the selection area corresponds to the display area of ​​the second information or the display area of ​​the third information changed by the area switching unit.

[0011] (5) The display device described in (1) may further include an expanded information display unit (for example, an expanded information display unit 34 described later) that displays expanded information of the first information, the expanded information display unit may further display the expanded information, or the second information display unit and the expanded information display unit may exchange the second information with the expanded information to display the expanded information, and the expanded information display unit may change the display area of ​​the expanded information so that the display area corresponds to the selection area selected by the area selection unit.

[0012] (6) The display device described in (5) may further include an area switching unit (for example, an area switching unit 25 described later) that changes at least one of the display area of ​​the second information and the display area of ​​the extended information, and the area selecting unit may change the selection area so that the selection area corresponds to the display area of ​​the second information or the display area of ​​the extended information changed by the area switching unit.

[0013] (7) The display device described in (3) may further include an extended information display unit (for example, an extended information display unit 34 described later) that displays the extended information of the first information, the extended information display unit may further display the extended information or the second information display unit, the third information display unit, and the extended information display unit may exchange the second information or the third information with the extended information to display the extended information, and the extended information display unit may change the display area of ​​the extended information so that the display area corresponds to the selection area selected by the area selection unit.

[0014] (8) The display device described in (7) may further include an area switching unit (for example, an area switching unit 25 described later) that changes at least one of the second information display area, the third information display area, and the extended information display area, and the area selecting unit may change the selection area so that the selection area corresponds to the second information display area, the third information display area, or the extended information display area changed by the area switching unit.

[0015] According to the present invention, it is possible to provide a display device with which an operator can visually and easily determine whether or not wood chips can be shredded during swing cutting. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a diagram showing a processing system incorporating a display device according to the present invention; Fig. 2A is a figure showing a position command for feed axes executed by a controller shown in Fig. 1, is calculated; Fig. Figure 2B is a figure showing a vibration command for the feed axes issued by the controller shown in Fig. 1, is calculated; Fig. Figure 2C is a figure showing a feed command obtained by subtracting the oscillation command shown in Fig. 2B, to the position command, shown in Fig. 2A, added; Fig. 3 is a diagram showing an example of second information displayed on a second information display unit in the display device shown in Fig. 1, are displayed; Fig. Fig. 4 is a diagram showing display examples of first information and second information displayed by display units in the display device shown in Fig. 1, are generated; and Fig. Fig. 5 is a diagram showing display examples of first information, extended information of the first information, and third information displayed by display units in the display device shown in Fig. 1, are generated. DETAILED DESCRIPTION OF THE INVENTION

[0016] An example of an embodiment of the present invention will be described below with reference to the accompanying drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals.

[0017] Fig. Fig. 1 is a diagram showing a processing system including a display device according to the present invention. The processing system 1 shown in Fig. 1, includes a machine tool 10, a controller 11 that controls the machine tool 10, and a display device 20.

[0018] The machine tool 10 includes a cutting tool 14, for example, a byte (tool). The cutting tool 14 performs machining on a workpiece having, for example, a tubular shape, a cylindrical shape, a conical shape, or a truncated cone shape. The shape of the workpiece W may be other than a cylindrical shape, and the machine tool 10 is not limited to a machine tool that performs machining and may be a machine tool that performs grinding, polishing, or the like. As described below in Fig. 1, it is assumed that turning is performed on the outer circumferential surface of the workpiece W, which is rotated and cylindrical, with the cutting tool 14. A description will be given using, as an example, a configuration in which the workpiece W is rotated and in which the cutting tool 14 oscillates along the generatrix of the outer circumferential surface of the workpiece W.

[0019] The machine tool 10 includes a plurality of drive axes 13. The individual drive axes 13 are controlled by the controller 11, such as a CNC (numerical control) or a PLC (programmable logic controller). Although Fig. 1 shows the machine tool 10 including three drive axes 13. The number of drive axes 13 is not limited, and the machine tool 10 can include any required number of drive axes. The drive axes 13 include a spindle M0 and at least two feed axes M1 and M2 that perform coordinated operation with the spindle M0. The spindle M0 includes a spindle motor or a servo motor. The feed axes M1 and M2 include a ball screw mechanism or a feed mechanism such as a linear slider and a servo motor that drives the feed mechanism.

[0020] In Fig. 1, it is assumed that the central axis line of the workpiece, which serves as the rotation axis of the workpiece W, is the z-axis, and that an axis line perpendicular to the z-axis is the x-axis. Moreover, the spindle M0 rotates the workpiece W around the central axis line (z-axis) of the workpiece. The feed axis M1 can both feed the cutting tool 14 in a first direction (hereinafter referred to as the machining direction) along the z-axis direction and reciprocate the cutting tool 14 in the first direction, resulting in swing of the cutting tool 14. The feed axis M2 can both feed the cutting tool 14 in a second direction (hereinafter referred to as the cutting direction) along the x-axis direction and reciprocate the cutting tool 14 in the second direction, resulting in swing of the cutting tool 14.When turning is performed on a workpiece having a cylindrical or tubular shape, the workpiece is rotated around the center axis (z-axis) of the workpiece, and the cutting tool 14 is fed only in the first direction (the machining direction) along the z-axis direction. In this case, the feed axis M2 becomes essentially unnecessary.

[0021] When turning is performed on a workpiece such as a conical, truncated conical, or the like whose outer diameter varies along the z-axis direction, the workpiece W is rotated around the center axis (z-axis) of the workpiece, and the cutting tool 14 is fed in the combined direction of the x-axis and z-axis directions. In this case, at least two feed axes M1 and M2 are needed to feed the cutting tool 14 in an oblique direction along the generatrix of the outer circumferential surface of the workpiece W. Both the feed axis M1 and the feed axis M2 are controlled, and therefore the cutting tool 14 is fed in an oblique direction along the generatrix of the outer circumferential surface of the workpiece W.

[0022] A machining program (NC program) that specifies machining conditions such as a spindle speed (S) and a feed rate (F) is generated and stored in the controller 11. The controller 11 includes an operator panel (not shown) that can be used to change the machining conditions and various parameter types specified in the machining program.

[0023] The controller 11 can calculate commands for individually operating the drive axes 13, such as the spindle M0, the feed axis M1 and the feed axis M2, according to the machining program and transmits the calculated commands to the corresponding drive axes 13, such as the spindle M0, the feed axis M1 and the feed axis M2. In an arrangement in which, as in the example of Fig. 1, the workpiece is rotated with the spindle M0 and in which the cutting tool 14 is fed with the feed axes M1, M2 and the like, the controller 11 transmits a command for a predetermined rotation speed to the spindle M0 and transmits a command for a predetermined target position to the feed axes M1, M2 and the like.

[0024] The machining system 1 includes a position detection device 15 for each of the drive axes 13, such as the spindle M0, the feed axis M1 and the feed axis M2, which detects the position of the drive axes 13. As shown in Fig. 1, in the arrangement in which the workpiece W is rotated with the spindle, a sensor that detects the rotational position (angle) of the workpiece W, for example, a rotary encoder, can be used as the position detecting device 15 of the spindle M0. The rotary encoder can also detect the rotational speed of the workpiece W. As the position detecting device 15 of the feed axis M1, shown in Fig. 1, a sensor that can detect the position of the cutting tool 14 in the machining direction of the workpiece W, for example, an encoder, can be used. As the position detecting device 15 of the feed axis M2, a sensor that can detect the position of the cutting tool 14, as described above, in the cutting direction of the workpiece W, for example, an encoder, can be used. However, as long as the position detecting devices 15 of the feed axes M1 and M2 detect the positions (the position of the cutting tool 14 in the example of Fig. 1) of the feed axes M1 and M2, any device can be used, and these are not limited to the encoders described above. The position detection devices 15 of the feed axes M1 and M2 can, for example, be a position measuring device arranged separately from the drive axis 13 and including a laser tracker, a three-dimensional position sensor, or the like. The controller controls the drive axes 13 so that the commands transmitted to the drive axes as described above match the position data of the drive axes 13 returned to the controller 11 from the position detection devices 15 of the drive axes 13.

[0025] In order to crush the wood chips generated during turning, the controller 11 further has the function of controlling the feed axis M1 so that the cutting tool 14 and the workpiece W are caused to swing relative to each other in the first direction (the machining direction) as described above to perform intermittent cutting. A feed command of the feed axis M1 for performing the intermittent cutting as described above is also calculated by the controller 11 according to the machining program. An operator uses the operator panel (not shown) of the controller 11 to change the machining conditions and various types of parameters, and can thereby specify the frequency, amplitude, and the like of the intermittent cutting feed command.The interrupted cutting described above means that the machining is performed on the workpiece W while the cutting tool 14 is brought into contact with and separated from the workpiece W at regular intervals, and is also called oscillating cutting or vibration cutting.

[0026] The feed command for the interrupted cutting described above is calculated, for example, by the following method. The controller 11 first calculates a position command for the feed axis M1 to feed in the first direction (the machining direction) along the z-axis direction in Fig. 1 based on a machining start point, a machining end point, the rotation speed of the spindle M0 (the rotation speed of the workpiece W in the example of Fig. 1), the feed rate through the feed axis M1 (the feed rate of the cutting tool 14 in the example of Fig. 1) and the like, which are set in the machining program. Next, based on the rotation speed, feed rate, and various parameter types described above, the controller 11 calculates the oscillation command of the feed axis M1 to generate the oscillation (reciprocating motion) of the cutting tool 14 in the machining direction described above. Furthermore, the controller 11 adds the position command and the oscillation command together to calculate the feed command (combination command) for intermittent cutting as described above.

[0027] Here is Fig. 2A is a figure showing the position command described above, a horizontal axis represents time, and a vertical axis represents the position (position command value) in the machining direction. In the position command, the position command value of the feed axis M1 increases linearly (see a straight line P) with time. Fig. Figure 2B is a figure showing the oscillation command described above. A horizontal line represents time, and a vertical line represents a position (position command value) in the machining direction. In the oscillation command, the position command value of the feed axis M1 increases and decreases periodically (see a wave-shaped curve S) with time. As shown in Fig. 2B, the amplitude and frequency in the vibration command are variable, and thus it is possible to obtain the vibration command of various vibration functions. In this example, the rotation speed of the workpiece W and the feed rate of the cutting tool 14 are individually kept constant, and thus the frequency and amplitude of the vibration command are also constant over time. Fig. Figure 2C is a figure showing a feed command (combination command) obtained by adding the oscillation command shown in Fig. 2B, to the position command, shown in Fig. 2A, a horizontal axis represents time and a vertical axis represents a position (position command value) in the machining direction. The path of the cutting tool 14 follows the feed command shown in Fig. 2C. As in Fig. 2C, by the feed command (see a wave-shaped curve Q), in one round of the reciprocating motion, the cutting tool 14 is moved backward solely by a predetermined amount of backward movement, and then moved forward solely by a predetermined amount of forward movement, so that movement is performed solely by an amount of movement corresponding to a difference between the two. As described above, in the present embodiment, the cutting tool 14 is fed in the machining direction by the feed axis M1 while reciprocating (being caused to swing) in the machining direction, thus performing intermittent cutting.

[0028] The oscillation command described above is a cosine waveform command, which is represented by the wave-shaped curve S in Fig. 2B and is defined by the following formula. Oscillation command = (K×F / 2)×cos(2π×S / 60×I×t)−(K×F / 2)

[0029] In formula (1), K represents a vibration amplitude magnification, F represents the amount of movement of the cutting tool 14 per rotation of the workpiece W, which corresponds to a feed amount per rotation [mm / rev], S represents the rotation speed of the workpiece W around the central axis line [min -1 ] or [rpm] and I represents an oscillation frequency increase.

[0030] Here, the oscillation frequency, i.e., the frequency of the oscillation command, corresponds to a term of (S / 60 × 1) in formula (1), and the oscillation amplitude, i.e., the amplitude of the oscillation command, corresponds to a term of (K × F / 2) in formula (1). However, the oscillation amplitude magnification K is a number equal to or greater than one, and the oscillation frequency magnification I is a non-integer number greater than zero (for example, a positive non-integer number such as 0.5, 0.8, 1.2, 1.5, 1.9, 2.3, or 2.5, ...). The oscillation amplitude magnification K and the oscillation frequency magnification I are constants.

[0031] In formula (1) described above, the oscillation command is a command in which the term (K × F / 2) is subtracted as an offset value with respect to a cosine wave in which the position of zero is a reference axis line. Consequently, the feed command (the wave-shaped curve Q in Fig. 2C), which is obtained by adding the oscillation command to the position command, a command that does not include the position command (the straight line in Fig. 2C) in the machining direction. Thus, the path of the position of the cutting tool 14 can be controlled based on the feed command (the wave-shaped curve Q) with the assumption that, in the machining direction of the cutting tool 14, the position according to the position command is an upper limit. In addition, the oscillation command of the cosine wave is provided as indicated in formula (1), and thus, as shown in the wave-shaped curve Q in Fig. 2C, large vibration at the machining start point (position with 0° in the horizontal axis) of the cutting tool 14 in the cutting direction of the cutting tool 14 is prevented from the beginning. The reason why the vibration frequency magnification I is not set as an integer is that in the case of a vibration frequency that is exactly equal to the number of rotations of the workpiece W around the central axis line, overlapping areas B1, B2 and the like (see Fig. 3), as described later, cannot be generated, and thus it is impossible to obtain the effect of shredded wood chips during swing cutting.

[0032] It is assumed that the above-described formula (1) is described in the machining program in the controller 11. The operator panel (not shown) of the machine tool 10 can provide the values ​​of the vibration amplitude magnification K and the vibration frequency magnification I of formula (1) described in the machining program in the controller 11. It is assumed that the rotation speed S [min - 1] of the workpiece W and the feed rate [mm / min] of the cutting tool 14 are previously set as machining conditions in the machining program in the controller 11. The controller 11 calculates the feed amount per rotation F (= feed / rotation speed S) in the above-described formula (1) from the feed rate and the rotation speed as described above, and can calculate the vibration command by the above-described formula (1) to which the values ​​of the vibration amplitude magnification K and the vibration frequency magnification I are previously supplied.

[0033] The machining system 1 of the present embodiment includes a display device 20 that displays information on the machine tool 10 when the cutting tool 14 and the workpiece W are caused to swing relatively in the machining direction to crush wood chips generated during turning, thereby performing intermittent cutting. As described above, the feed command of the feed axis M1 for performing intermittent cutting is calculated by the controller 11, and the display device 20 is a device that helps the operator visually perceive the feed command as described above and the actual position of the feed axis M1 driven by the feed command.However, in a method of simply displaying the command value of the intermittent cutting feed command on a display screen, it is difficult for the operator to determine whether or not the wood chips can be crushed with the cutting tool 14. Even in a method of detecting, using the position detecting device 15, the actual position of the feed axis M1 driven by the intermittent cutting feed command to display the detected value thereof on the display screen, it is difficult for the operator to determine from the display screen whether or not the wood chips can be crushed.

[0034] Therefore, as in Fig. 1, the display device 20 of the present embodiment of the invention includes an information acquisition unit 21, an area selection unit 23, an area switching unit 25, and a display unit 30.

[0035] Although in the arrangement example in Fig. 1, the display device 20 is arranged outside and away from the controller 11, the display device 20 may be provided in the operator panel (not shown) of the machine tool 10 or may be provided built into the controller 11. The display unit 30 may be a display panel unit such as an LCD (liquid crystal display) panel or an OLED (organic light-emitting diode) panel.

[0036] The information acquisition unit 21 acquires position information of the feed axes M1 and M2 at regular time intervals when intermittent cutting is performed. The regular time intervals can be set to integer multiples of the sampling control period (for example, the command cycle distribution period) of the controller 11. The position information acquired by the information acquisition unit 21 is either the value of the feed command for intermittent cutting or the actual positions (position feedback) of the feed axes M1 and M2 driven by the feed command.In addition, when the actual positions of the feed axes M1 and M2 are obtained as the position information of the feed axes M1 and M2, the actual positions may be the output values ​​of the encoders included in the servo motors of the feed axes M1 and M2, or positions of the movement end of the feed axes M1 and M2, for example, the position of the tip end area of ​​the cutting tool 14, which are measured remotely with the position measuring device such as a laser tracker or a three-dimensional position sensor.

[0037] The information acquisition unit 21 acquires, at regular intervals, in addition to the position information of the feed axes M1 and M2, control information when intermittent cutting is performed, such as torque information, speed information, or acceleration information. The torque information, speed information, and acceleration information acquired by the information acquisition unit 21 may be feed command values ​​for intermittent cutting or feedback values ​​of the feed axes M1 and M2 driven by the feed command. Actual torque (torque feedback) can be determined, for example, by detecting the drive current of the servomotors of the feed axes M1 and M2. Actual speed (speed feedback) can be determined, for example, from the output values ​​of the encoders included in the servomotors of the feed axes M1 and M2.Actual acceleration (acceleration feedback) can be determined, for example, from the output values ​​of an acceleration sensor located near the tip end of the cutting tool.

[0038] The information acquisition unit 21 obtains as rotation information the relative rotation speed and the rotation angles of the workpiece W and the cutting tool 14. In the case of Fig. In the arrangement shown in Figure 1, the rotation speed of the spindle M0 (the rotation speed of the workpiece W) is set in advance in the machining program stored in the controller 11, and the information acquisition unit 21 acquires the rotation speed of the spindle M0 from the controller 11 as rotation information. Furthermore, as described above, the rotary encoder is used as the position detecting device 15 of the spindle M0, and the controller 11 can detect the rotation angle of the spindle M0 with the rotary encoder during intermittent cutting. Therefore, the information acquisition unit 21 can acquire not only the rotation speed but also the rotation angle of the spindle M0 from the controller 11 as rotation information.The information acquisition unit 21 also has the function of storing the acquired temporal position information of the feed axes M1 and M2, the other control information (torque information, speed information, or acceleration information), and the rotation speed and rotation angle of the spindle M0 in a memory (not shown).

[0039] The display unit 30 displays the information acquired by the information acquisition unit 21. The display unit 30 includes a first information display unit 31, a second information display unit 32, a third information display unit, and an extended information display unit 34. The first information display unit 31 displays first information indicating a position to which the cutting tool 14 is fed relative to the workpiece W. Specifically, the first information display unit 31 displays, based on the temporal position information of the feed axes M1 and M2 acquired by the information acquisition unit 21, the first information indicating a movement distance (movement path) of the feed axes M1 and M2, which is the movement distance (movement path) of the cutting tool 14.The extended information display unit 34 displays extended information of the first information. However, the first displayed information may be the output values ​​of the encoders built into the servomotors of the feed axes M1 and M2, or the position of the tip end area of ​​the cutting tool 14 measured remotely with the position measuring device. In other words, the first information may be data based on the position command values ​​of the feed axes M1 and M2, or data based on the actual positions (position feedback) of the feed axes M1 and M2.

[0040] The third information display unit 33 displays third information indicating a temporal change of the position information of the feed axes M1 and M2. Specifically, the third information display unit 33 displays the third information indicating a temporal change of the positions of the feed axes M1 and M2 based on the temporal position information of the feed axes M1 and M2 acquired by the information acquisition unit 21. For example, when the feed command for interrupted cutting is acquired by the information acquisition unit 21, the Fig. 2. However, the displayed third information may be information obtained by relating the output values ​​of the encoders built into the servomotors of the feed axes M1 and M2 with time, or information obtained by relating the position of the tip end of the cutting tool 14, which is remotely measured with the position measuring device, with time. In other words, the third information may be data based on the position command values ​​of the feed axes M1 and M2, or waveform data based on the actual positions of the feed axes M1 and M2.

[0041] The third information display unit 33 also displays third information indicating a temporal change of the control information (torque, speed, or acceleration) of the feed axes M1 and M2 based on temporal control information other than the position information of the feed axes M1 and M2 acquired from the information acquisition unit 21, for example, the temporal torque information, the temporal speed information, or the temporal acceleration information. The third information may be data based on command values ​​of the torques, speeds, or accelerations of the feed axes M1 and M2, or waveform data based on the actual torques (torque feedback), actual speeds (speed feedback), or actual accelerations (acceleration feedback) of the feed axes M1 and M2.

[0042] The second information display unit 32 displays second information indicating a relationship between the phase of the spindle M0 and the positions of the feed axes M1 and M2. Specifically, based on the temporal position information of the feed axes M1 and M2 and the rotation information of the spindle M0 acquired by the information acquisition unit 21, the second information display unit 32 displays second information in which the positions of the feed axes M1 and M2 per rotation (or two rotations, three rotations, etc.) of the spindle M0 are superimposed (inverted) and displayed.The second information display unit 32 displays, for example, the second information by dividing the third information displayed by the third information display unit 33 into pieces of partial data per rotation angle (360° or 2π) corresponding to one rotation of the spindle M0 (or rotation angles corresponding to multiple rotations (two rotations, three rotations, ...)) and sequentially shifting the pieces of partial data so that the pieces of partial data are aligned with the start point (for example, an origin on the horizontal axis of the . Fig. 3) the third information matches.

[0043] The rotation angle of the workpiece W can be calculated from the rotation speed, which is a setting value set in the machining program in the controller 11, or the rotation angle of the workpiece W can be actually detected by the encoder built into the spindle M0. The display device 20 can perform the detection of the rotation angle of the workpiece W and the acquisition of the position information of the feed axes M1 and M2 as described above at regular intervals to display the second information in which the actual rotation angles and the position information of the feed axes M1 and M2 are linked.

[0044] Fig. 3 is a diagram showing an example of the second information displayed in the second information display unit 32. In Fig. 3, a horizontal axis represents the rotation angle (i.e. the phase) of the spindle M0 and a vertical axis represents the positions (i.e. the positions of the feed axes M1 and M2) in the machining direction (i.e. the first direction along the direction of the z-axis in Fig. 1). A curve A1 and a curve A2, which are Fig. 3 correspond, for example, to the parts of the partial data obtained by dividing the time data (the waveform curve Q) of the feed command into Fig. 2 per rotation of the workpiece W, which is the second information. Curve A1 indicates the second information in the first rotation of the workpiece W, and curve A2 indicates the second information in the second rotation of the workpiece W. The illustration of the second information in the third and subsequent rotations of the workpiece W is omitted for simplicity. The second information of curves A1 and A2 and the like indicate a path of the cutting tool 14 on the workpiece W being rotated. In Fig. 3, a plurality of linear dashed lines C1, C2, C3, ... extending obliquely are shown. The dashed lines C1, C2 and C3 correspond to the position command (the dotted straight line P) shown in Fig. 2C, and the intervals between the dashed lines C1, C2 and C3 in the direction of the vertical axis in Fig. 3 correspond to the feed rate per rotation F.

[0045] In Fig. 3, the curves A1 and A2 overlap in the two areas B1 and B2. In the areas B1 and B2, the maximum value of the curve A1 with respect to the dashed line C1 is greater than the minimum value of the curve A2 with respect to the dashed line C2. In the overlapping areas B1 and B2, when the cutting tool 14 performs machining along the path of the curve A2, the cutting tool 14 is separated from the workpiece W, with the result that the workpiece W is not machined. The overlapping areas B1 and B2 are periodically generated as described above, thus enabling intermittent cutting as described previously. Fig. In the example shown in Figure 3, wood chips are generated individually in the overlapping areas B1 and B2 by operating according to curve A2. In other words, the two wood chips are generated in curve A2 of the second rotation.

[0046] Therefore, the operator checks for the presence of overlapping areas B1 and B2, where the previous curve A1 and the subsequent curve A2 overlap, and can determine whether wood chips can be crushed. If the overlapping areas B1, B2, etc. are not generated, the operator changes the vibration frequency and vibration amplitude in the Fig. 2B. This switching can be performed by adjusting the setting values ​​such as a spindle rotation speed S, the feed rate per rotation F, and the vibration frequency magnification I in the machining program in the controller 11. In order to create the intended overlapping areas B1 and B2, the operator preferably switches the vibration frequency and vibration amplitude while visually observing the second information displayed on the display unit 30 of the display device 20, which will be described later.

[0047] The display unit 30 configured as described above displays the first information and the second information. Specifically, the first information display unit 31 displays the first information, and the second information display unit 32 displays the second information. Here, the second information display unit 32 changes the display area of ​​the second information so that the display area corresponds to a selection area selected by the area selection unit 23, which will be described later. The display unit 30 can further display at least one of the first information and the third information. Specifically, the expanded information display unit 34 can further display expanded information of the first information, and the third information display unit 33 can further display the third information.Alternatively, the display unit 30 may temporarily exchange the second information with at least one of the first information and the third information to generate a display. Specifically, the second information display unit 32 and the extended information display unit 34 may exchange the second information with the extended information to display the extended information, or the second information display unit 32 and the third information display unit 33 may exchange the second information with the third information to display the third information.Alternatively, the second information display unit 32, the third information display unit 33, and the extended information display unit 34 may exchange the second information or the third information with the extended information to display the extended information. Here, the extended information display unit 34 may change the display area of ​​the extended information to match the selection area selected by the area selection unit 23, and the third information display unit 33 may change the display area of ​​the third information to match the selection area selected by the area selection unit 23.

[0048] Fig. 4 is a figure showing examples of displays of the first information and the second information, and Fig. 5 is a figure showing examples of displaying the first information, the extended information of the first information, and the third information. In Fig. 4, the first information display unit 31 displays first information, which is a movement distance (movement path) shown by the position (z position in the machining direction) of the feed axis M1 and the position (x position in the cutting direction) of the feed axis M2 (left figure), and the second information display unit 32 displays second information, which is information shown by superimposing the positions (z position in the machining direction) of the feed axis M1 per rotation of the spindle M0 (right figure). The first information display unit 31 can display a selection area A selected by the area selection unit 23, so that the selection area A corresponds to the first information (left figure). The second information (right figure) is information corresponding to the previously described Fig. 3 correspond.

[0049] As described above, the second information, which is information shown by superimposing the position (z position in the machining direction) of the feed axis M1 per rotation of the spindle M0, is displayed (right figure). Thus, as described previously, the operator checks the presence of overlapping areas of the curves in the second information, and can thus easily determine whether or not wood chips can be crushed. The selection area A corresponding to the display area of ​​the second information is displayed together with the first information corresponding to the movement distance (movement path) shown by the position (z position in the machining direction) of the feed axis M1 and the position (x position in the cutting direction) of the feed axis M2 (left figure). Thus, the operator can check which part of the second information is displayed in the movement distance (movement path).

[0050] The second information display unit 32 may display, as the second information, information shown by superimposing the position (x position in the cutting direction) of the feed axis M2 per rotation of the spindle M0, or information shown by superimposing a position in the combined direction of the machining direction of the feed axis M1 and the cutting direction of the feed axis M2 per rotation of the spindle M0.

[0051] On the other hand, exchange in Fig. 5 the second information display unit 32 and the extended information display unit 34 temporarily display the Fig. 4 with the extended information of the first information, which is extended information of the first information, the display area of ​​which is changed to correspond to the selection area A, and then generates a display (top right of the figure). The second information display unit 32 and the third information display unit 33 may further display the second information shown in Fig. 4, exchange information with the third information, which is information indicating a temporal change of the position (z position in the machining direction) of the feed axis M1, and then generate a display (lower figure).

[0052] In the extended information of the first information (top right figure), the curve here corresponds to the generatrix of the outer circumferential surface of the workpiece W. In this way, the extended information of the first information is displayed, and thus the operator can detect excessive cutting of the workpiece W, insufficient cutting of the same, or the like.As the extended information of the first information or the third information, which is information indicating the temporal change of the position (z position in the machining direction) of the feed axis M1, the position command value and the actual position (position feedback) are displayed so as to be superimposed (upper right figure, lower figure), and thus the operator checks a shift between the position command value and the actual position (position feedback), so that he is able to check whether or not the setting of the machine tool 10 and the controller 10 (for example, the setting of a servo parameter) is appropriate.

[0053] The third information display unit 33 can display, as the third information, control information other than the positions of the feed axes M1 and M2, for example, information indicating a temporal change in torque, speed, or acceleration. As described above, as the information indicating the temporal change in the torques, speeds, or accelerations of the feed axes M1 and M2, the command values ​​and the actually detected values ​​(feedback) are displayed to be superimposed, and thereby the operator checks for a shift between the command values ​​and the actually detected values ​​(feedback) to be able to check whether or not the setting of the machine tool 10 and the controller 11 (for example, the setting of the servo parameter) is appropriate.

[0054] The third information display unit 33 may display, as the third information, information indicating a temporal change in the position (x position in the cutting direction) of the feed axis M2 or information indicating a temporal change in the combined direction of the machining direction of the feed axis M1 and the cutting direction of the feed axis M2.

[0055] In addition, instead of the Fig. 4 and Fig. 5, when the second information and the third information are displayed, time or the rotation angle can be specified in the vertical axis direction, and the position command value of the feed axis or the actual position can be specified in the horizontal axis direction.

[0056] The area selection unit 23 selects a piece of the first information as the selection area A. Here, the area switching unit 25 changes at least one of the second information display area, the third information display area, and the extended information display area of ​​the first information so that the changed display area corresponds to the selection area A selected by the area selection unit 23. For example, the area selection unit 23 may set the start point and end point of a piece of first information to select the selection area. Here, the area switching unit 25 changes the display scales of the vertical axes or the horizontal axes of the second information and the third information to display the information equally with a time range corresponding to the selected selection area, with the result that the display area and the selection area are aligned with each other.Since the first information, the second information, and the third information are pieces of the temporal information acquired by the information acquisition unit 21 at the same time, when the area selection unit 23 selects the piece of the first information as the selection area, the area switching unit 25 can determine a time area corresponding to the selection area, and display pieces of the second information and the third information in this time area, so that the display area of ​​the first information can be made consistent with the display area of ​​the second information.In this way, the third information display unit 33 acquires a time range corresponding to the selected first information to display the third information in the time range corresponding to the selection range, and changes the display range to display the third information in the time range, with the result that the selection range and the display range are matched with each other.

[0057] The area switching unit 25 changes at least one of the display area of ​​the second information, the display area of ​​the third information, and the display area of ​​the extended information of the first information. Here, the area selection unit 23 changes the selection area so that the selection area corresponds to the display area of ​​the second information, the display area of ​​the third information, or the display area of ​​the extended information of the first information changed by the area switching unit 25.

[0058] The area selection unit 23 may, for example, include a touch panel provided in the display unit 30. In this way, the selection area selected in the area selection unit 23 is changed. Here, the display unit 30 changes, in a coordinated manner, the display area of ​​the second information, the display area of ​​the third information, and the display area of ​​the extended information of the first information, so that the changed display areas correspond to the changed selection area. Fig. 4 For example, when the operator operates the touch panel to move the selection area A corresponding to the first information, the display area of ​​the second information is also moved in a coordinated manner. In Fig. 5 For example, when the operator operates the touch panel to move the selection area A corresponding to the first information, the display area of ​​the extended information of the first information and the display area of ​​the third information are also moved in a coordinated manner. As described above, the changes in the selection area A of the first information, the display area of ​​the second information, the display area of ​​the third information, and the display area of ​​the extended information of the first information are executed in a coordinated manner, thus simplifying the operator's inspection operation.

[0059] The area switching unit 25 may, for example, include a touch panel provided in the display unit 30. In Fig. 4 For example, when the operator operates the touch panel to move the display area of ​​the second information vertically, the selection area A corresponding to the first information is also moved sideways in a coordinated manner. Fig. 5 For example, when the operator operates the touch panel to move the extended information display area of ​​the first information or the third information display area, the selection area A corresponding to the first information is also moved in a coordinated manner, and the extended information display area of ​​the first information is moved according to the moved selection area A. As described above, the changes of the selection area A of the first information, the second information display area, the third information display area, and the extended information display area of ​​the first information are carried out in a coordinated manner, and therefore the operator's checking operation is simplified.

[0060] As described above, with the display device 20 of the present embodiment, the operator can easily determine whether or not wood chips are being crushed during intermittent cutting (oscillating cutting). This allows the operator to more reliably adjust the oscillation amplitude to crush the wood chips, and thus, it is possible to enable intermittent oscillation in which wood chips are crushed as intended.

[0061] If a kickback is provided in the unit of the drive mechanism of the cutting tool 14 or the stability of the drive mechanism is low, vibrations are likely to occur during intermittent cutting, and thus the precision of the position of the cutting tool 14 is not secured. For example, even if the feed axis M1 is driven by the feed command for intermittent cutting, the actual position of the cutting tool 14 is likely to not fully correspond to the curves A1 and A2 as shown in Fig. 3. In other words, even if the command value is considered to be capable of shredding wood chips, in reality, the wood chips are likely not to be shredded as intended. In this regard, a display device 20 of the present embodiment detects a temporal change in the actual position of the feed axis M1 with the position detecting device 15, such as an encoder, and the previously described second information is generated based on the detected data and displayed on the display unit 30. Therefore, the operator sees the second information based on the actual positions of the feed axes M1 and M2 as described above, and can therefore accurately determine whether or not the wood chips are actually being shredded.

[0062] When turning is performed on the cylindrical workpiece W, the rotational speed S of the workpiece W is preferably constant. On the other hand, the diameter at a part of the workpiece W with which the tip end of the cutting tool 14 comes into contact is determined according to the feed position of the cutting tool 14 in the machining direction (direction along the z-axis direction in Fig.1) when turning is performed on a workpiece having a conical, truncated conical, or similar shape. In this case, if the rotational speed S of the workpiece W is constant, the surface speed (which is the cutting speed) at the part of the workpiece W that comes into contact with the cutting tool 14 changes according to the position of the cutting tool 14 in the machining direction, and thus, it is likely that a uniform machined surface cannot be achieved. Therefore, in order to keep the surface speed constant, the rotational speed S of the workpiece W should be determined by a function that changes according to the diameter of the part of the workpiece W with which the tip end of the cutting tool 14 comes into contact.

[0063] The above-described controller 11 and display device 20 are equipped with a computer including a memory such as a ROM (Read Only Memory) and a RAM (Random Access Memory), a CPU (control processor), and a communication control unit connected to each other via a bus. Furthermore, individual functional units such as the information acquisition unit 21, the first information display unit 31, the second information display unit 32, the third information display unit 33, and the extended information display unit 34 constituting the display device 20 can be achieved by coordinating the CPU and memory built into the computer and a control program stored in the memory.

[0064] Although the embodiment of the present invention is described above, the present invention is not limited to the above-described embodiment, and numerous modifications and variations are possible. For example, although the above-described embodiment illustrates the arrangement in which the workpiece W is rotated and the cutting tool 14 oscillates along the generatrix of the outer circumferential surface of the workpiece W, the present invention is not limited to this arrangement.The machine tool according to the present invention may have an arrangement in which the spindle M0, which relatively rotates the workpiece W and the cutting tool 14 around the central axis line of the workpiece W, and at least the feed axes M1, M2, which relatively feed the workpiece W and the cutting tool 14 in the machining direction along the central axis line, and the like are controlled, and thus turning is performed on the workpiece W. For example, an arrangement may be adopted in which the cutting tool is rotated around the central axis line of the workpiece W and in which the workpiece W swings with respect to the cutting tool 14, or an arrangement in which the workpiece W is rotated and in which the workpiece W swings with respect to the cutting tool 14 in a direction along the generatrix of the outer circumferential surface of the workpiece W.In the present invention, a machining method in which the cutting tool 14 is rotated around the central axis line of the workpiece W to perform cutting on the workpiece W is adopted as a kind of turning. EXPLANATION OF REFERENCE SYMBOLS 1 processing system 10 Machine tool 11 Control 13 Drive axle 14 Cutting tool 15 Position detection device 20 display device 21 Information gathering unit 23 Area selection unit 25 Range change unit 30 display unit 31 Display unit for initial information 32 Display unit for second information 33 Display unit for third information 34 advanced information display unit M0 spindle M1, M2 feed axis W workpiece

Claims

[1] A display device (20) that receives and displays information about a machine tool (10), wherein the machine tool comprises a spindle (M0) for relative rotation of a workpiece (W), a cutting tool (14) and at least one feed axis (M1, M2) for relative advancement of the workpiece (W) and the cutting tool (14) and performs the machining of the workpiece (W) while the cutting tool (14) and the workpiece (W) are set into oscillation relative to each other, the display device (20) comprising: a display unit for initial information (31) that displays initial information indicating a position to which the cutting tool (14) is advanced relative to the workpiece (W); a display unit for second information (32) that displays second information indicating a relationship between a phase of the spindle (M0) and a position of the feed axis (M1, M2), so that it is possible to determine whether the toolpaths overlap due to the relative vibration between the cutting tool (14) and the workpiece (W); and a range selection unit (23) that selects a portion of the initial information as a selection range, wherein the display unit for second information (32) changes the display area of ​​the second information such that the display area corresponds to the selection area selected by the area selection unit (23). [2] The display device (20) according to claim 1 further comprising: a range change unit (25) that changes the display area of ​​the second piece of information, wherein the range selection unit (23) can change the selection range so that the selection range corresponds to the display range of the second information, which is changed by the range change unit (25). [3] The display device (20) according to claim 1 further comprising: a display unit for third information (33) that displays third information indicating a temporal change in the position information, torque information, speed information and acceleration information of the feed axis (M1, M2), wherein the third information display unit (33) further displays the third information, or the second information display unit (32) and the third information display unit (33) exchange the second information with the third information to display the third information, and The display unit for third information (33) changes the display area of ​​the third information so that the display area corresponds to the selection area chosen by the area selection unit (23). [4] The display device (20) according to claim 3 further comprising: a range change unit (25) that changes at least one of the display ranges of the second information and the display range of the third information, wherein the range selection unit (23) changes the selection range so that the selection range corresponds to the display range of the second information or the display range of the third information, which is changed by the range change unit (25). [5] The display device (20) according to claim 1 further comprising: an enhanced information display unit (34) that displays enhanced information of the initial information, wherein the extended information display unit (34) further displays the extended information or the second information display unit (32) and the extended information display unit (34) exchange the second information with the extended information in order to display the extended information, and The extended information display unit (34) changes the display area of ​​the extended information so that the display area corresponds to the selection area chosen by the area selection unit (23). [6] The display device (20) according to claim 5, further comprising: a range change unit (25) that changes at least one of the display ranges of the second information and the display range of the extended information, and wherein the range selection unit (23) changes the selection range so that the selection range corresponds to the display range of the second information or the display range of the extended information, which is changed by the range change unit (25). [7] The display device (20) according to claim 3 further comprising: an extended information display unit (34) that displays the extended information of the first information, wherein the enhanced information display unit (34) further displays the enhanced information or the second information display unit (32), the third information display unit (33) and the enhanced information display unit (34) exchange the second information or the third information with the enhanced information in order to display the enhanced information, and The extended information display unit (34) changes the display area of ​​the extended information so that the display area corresponds to the selection area chosen by the area selection unit (23). [8] The display device (20) according to claim 7 further comprising: a range change unit (25) that changes at least one of the display range of the second information, the display range of the third information and the display range of the extended information, wherein the range selection unit (23) changes the selection range so that the selection range corresponds to the display range of the second information, the display range of the third information or the display range of the extended information which is changed by the range change unit (25).

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