Processing condition determination support device

Abstract

To suppress chatter vibration during cutting work.SOLUTION: A working condition determination support device comprises: an input reception part that receives input of tool information including information concerning specification of a tool attached to a machine tool, and work-piece information including information concerning material quality of a work-piece which is cut by the tool attached to the machine tool; a storage part that stores machine tool information including information concerning vibration characteristic of the machine tool; and a recommendation working condition determination part that determines recommendation working condition within a range excluding a working condition range in which forced chatter vibration specified by use of the machine tool information occurs, and within a range of a tool proper rotational speed which has been predetermined for each combination of the tool information and the work-piece information, and outputs information representing the recommendation working condition to an output part.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure relates to a machining condition determination support device. [Background technology]

[0002] Patent Document 1 discloses a technology in which a sensor is used to measure the vibration of a machine tool during cutting processing by the machine tool, the resonant frequency of the machine tool during cutting processing is identified, and a stability limit diagram is created using the identified resonant frequency. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2021-146436 Summary of the Invention [Problem to be solved by the invention]

[0004] Generally, a stability limit diagram shows the range of machining conditions under which machining is possible without causing self-excited chatter vibration in the tool or workpiece. However, even if machining conditions are determined using a stability limit diagram, there are cases in which the desired machining accuracy cannot be obtained. [Means for solving the problem]

[0005] The present disclosure can be realized in the following forms.

[0006] (1) According to one aspect of the present disclosure, there is provided a machining condition determination support device that supports the determination of machining conditions for cutting. The machining condition determination support device includes an input receiving unit that receives input of tool information including information on specifications of a tool attached to a machine tool and workpiece information including information on the material of a workpiece to be cut by the tool attached to the machine tool, a storage unit that stores machine tool information including information on vibration characteristics of the machine tool, and a recommended machining condition determination unit that determines recommended machining conditions within a range that excludes a range of machining conditions that generates forced chatter vibration identified using the machine tool information from a range of machining conditions that does not generate self-excited chatter vibration due to changes in cutting resistance in the cutting, and that is also within a range of appropriate rotational speeds for the tool that is predetermined for each combination of the tool information and the workpiece information, and outputs information representing the recommended machining conditions to an output unit. According to the machining condition determination support device of this embodiment, the recommended machining condition determiner outputs recommended machining conditions that can suppress not only the occurrence of self-excited chatter vibration but also the occurrence of forced chatter vibration. Therefore, by determining the machining conditions in accordance with the recommended machining conditions, it is possible to prevent the desired machining accuracy from being unavailable. (2) In the machining condition determination support device of the above form, the recommended machining condition determination unit may generate an additional stability limit diagram in which the recommended machining conditions are added to a stability limit diagram that represents the relationship between the rotational speed of the tool and the cutting depth at which self-excited chatter vibration does not occur, and output the additional stability limit diagram to the output unit as information representing the recommended machining conditions. According to the machining condition determination support device of this embodiment, machining conditions can be determined by referring to an additional stability limit diagram in which recommended machining conditions are added to a stability limit diagram. (3) In the processing condition determination support device of the above form, the recommended processing condition determination unit may determine a plurality of the recommended processing conditions and a recommended ranking of the plurality of the recommended processing conditions, and output information including the recommended processing conditions and the recommended ranking to the output unit as information representing the recommended processing conditions. According to the machining condition determination support device of this aspect, machining conditions can be selected from a plurality of recommended machining conditions, and the machining conditions can be determined with reference to the recommended order. (4) In the machining condition determination support device of the above form, the machine tool information may include information on the natural frequency of the machine tool, and the range of machining conditions that cause forced chatter vibration may include the rotational speed of the tool corresponding to the natural frequency. According to the machining condition determination support device of this aspect, it is possible to prevent the rotational frequency of the tool and the natural frequency of the machine tool from overlapping to cause forced chatter vibration. (5) In the machining condition determination support device of the above form, the machine tool information may include information on the natural frequency of the machine tool, and the range of machining conditions that cause forced chatter vibration may include a rotational speed of the tool that corresponds to the cutting edge passing frequency of the tool. According to the machining condition determination support device of this embodiment, it is possible to prevent the cutting edge passing frequency and the natural frequency of the machine tool from overlapping and causing forced chatter vibration. The present disclosure can be realized in various forms other than a machining condition determination support device, such as a machine tool or a machining condition determination support method. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view showing a schematic configuration of a machine tool. [Figure 2] FIG. 2 is an explanatory diagram showing the functional configuration of a control device. [Figure 3] 10 is a flowchart showing the contents of a recommended processing condition determination process. [Figure 4] FIG. 10 is an explanatory diagram showing an example of a stability limit line. [Figure 5] FIG. 10 is an explanatory diagram showing an example of an additional stability limit line. DETAILED DESCRIPTION OF THE INVENTION

[0008] A. First embodiment: 1 is a perspective view showing a schematic configuration of a machine tool 11 according to a first embodiment. In this embodiment, the machine tool 11 is configured as a vertical machining center, and includes a bed 20, a saddle 30, a table 40, a column 50, a spindle unit 60, and a control unit 100.

[0009] Bed 20 is disposed at the lower end of machine tool 11. Above the front portion of bed 20, a saddle 30 and a table 40 are disposed, in that order from bottom to top. Saddle 30 is supported by bed 20, and moves together with table 40 along the front-rear axis (Y-axis) of machine tool 11 by a servo motor and a ball screw (not shown). Table 40 is supported by saddle 30, and moves along the left-right axis (X-axis) of machine tool 11 by a servo motor and a ball screw (not shown). A workpiece WK is fixed to table 40. Workpiece WK is fixed to table 40, for example, via a fixing jig (not shown).

[0010] A column 50 is fixed to the upper surface of the rear portion of bed 20. A spindle device 60 is disposed in front of column 50 and above table 40. The spindle device 60 includes a spindle housing 62, a spindle 65, and a spindle motor 67. The spindle housing 62 is supported by column 50 and moves along the vertical axis (Z-axis) of machine tool 11 by a servo motor and a ball screw (not shown). The spindle 65 is supported by the spindle housing 62. A tool TL is attached to the spindle 65. The spindle motor 67 rotates the spindle 65 about a rotation axis parallel to the vertical axis (Z-axis) of machine tool 11. A servo motor, for example, can be used as the spindle motor 67.

[0011] The tool TL includes a cutting tool BD and a tool holder HD. The cutting tool BD has a blade that cuts the workpiece WK. The cutting tool BD is fixed to the spindle 65 via the tool holder HD. In this embodiment, the cutting tool BD is an end mill. For example, a BT shank, a BBT shank, an HSK shank, a CAPTO shank, or the like can be used as the tool holder HD. Note that in other embodiments, the cutting tool BD and the tool holder HD may be integrated.

[0012] The control device 100 is configured as a computer including a CPU 101, a memory 102, an input / output interface 103, and an internal bus 104. An input device 105 and a display device 106 are connected to the control device 100. The input device 105 is configured, for example, by a plurality of operation buttons. The display device 106 is configured, for example, by a liquid crystal display. The input device 105 and the display device 106 may be integrated as a touch panel. Note that the memory 102 may be referred to as a storage unit, and the display device 106 may be referred to as an output unit.

[0013] The CPU 101 executes a computer program stored in the memory 102 to function as the NC control unit 110, an input receiving unit 121 of the machining condition determination support unit 120 (described later), and a recommended machining condition determination unit 125. The NC control unit 110 controls each motor of the machine tool 11, such as the spindle motor 67, in accordance with the NC program to bring the rotating tool TL into contact with the workpiece WK and perform cutting on the workpiece WK. To generate an NC program, it is necessary to determine the tool rotation speed, feed rate, and depth of cut. The tool rotation speed refers to the rotation speed of the tool TL, in other words, the rotation speed of the spindle 65. The feed rate refers to the movement speed of the tool TL or the workpiece WK. In this embodiment, since the table 40 to which the workpiece WK is fixed moves, the feed rate refers to the movement speed of the workpiece WK, in other words, the movement speed of the table 40. The depth of cut refers to the depth of cut of the tool TL into the workpiece WK.

[0014] The machining condition determination support unit 120 determines recommended machining conditions using the tool information, workpiece information, and machine tool information, and outputs the recommended machining conditions to support the operator in determining the machining conditions. The tool information includes information on the specifications of the cutting tool BD and information on the specifications of the tool holder HD. The workpiece information includes information on the material of the workpiece WK. The machine tool information includes information on the vibration characteristics of the machine tool 11.

[0015] Fig. 2 is an explanatory diagram showing the functional configuration of the control device 100. In Fig. 2, the NC control unit 110 is not shown. The control device 100 includes an input receiving unit 121, a recommended machining condition determining unit 125, and a memory 102. In the following description, a part of the control device 100 that includes the input receiving unit 121, the recommended machining condition determining unit 125, and the memory 102 is referred to as a machining condition determination support unit 120. Note that the machining condition determination support unit 120 may also be referred to as a machining condition determination support device 120.

[0016] The input receiving unit 121 receives input of tool information and workpiece information. The tool information includes information on the specifications of the cutting tool BD and the specifications of the tool holder HD. The information on the specifications of the cutting tool BD includes, for example, the type of the cutting tool BD, the number of cutting edges of the cutting tool BD, the dimensions of the cutting tool BD such as the outer diameter, the appropriate cutting speed range of the cutting tool BD, and information on the material of the cutting tool BD. The type of cutting tool BD refers to an end mill, a face milling cutter, a drill, etc. The information on the specifications of the tool holder HD includes, for example, the type of the tool holder HD, the dimensions of the tool holder HD such as the outer diameter, and information on the material of the tool holder HD. The type of tool holder HD refers to a BT shank, a BBT shank, an HSK shank, a CAPTO shank, etc. The workpiece information includes information on the material of the workpiece WK. The tool information and workpiece information are input to the input receiving unit 121 via the input device 105 and then transmitted to the recommended machining condition determination unit 125.

[0017] The recommended machining condition determination unit 125 determines recommended machining conditions for cutting using the tool information and workpiece information received from the input reception unit 121 as well as the machine tool information stored in memory 102, and displays information indicating the recommended machining conditions on the display device 106. The machine tool information includes information on the vibration characteristics of the machine tool 11. In this embodiment, the machine tool information includes information on the natural frequency of the spindle housing 62 as information on the vibration characteristics of the machine tool 11. The recommended machining conditions are determined by a recommended machining condition determination process described below.

[0018] Fig. 3 is a flowchart showing the contents of the recommended machining condition determination process executed by the machining condition determination support unit 120. Fig. 4 is an explanatory diagram showing an example of a stability limit diagram SD1. Fig. 5 is an explanatory diagram showing an example of an additional stability limit diagram SD2. In the stability limit diagram SD1 and the additional stability limit diagram SD2, the horizontal axis represents the tool rotation speed, and the vertical axis represents the axial cutting depth.

[0019] 3 is started by the machining condition determination support unit 120 when, for example, a start button provided on the input device 105 is pressed. First, in step S110, the input receiving unit 121 of the machining condition determination support unit 120 receives input of tool information and workpiece information from the input device 105.

[0020] Next, in step S120, the recommended machining condition determination unit 125 of the machining condition determination support unit 120 uses the tool information and workpiece information to identify a range of machining conditions under which self-excited chatter vibration does not occur at the machining point. Self-excited chatter vibration occurs, for example, due to changes in cutting resistance caused by the regenerative effect. In this embodiment, the recommended machining condition determination unit 125 identifies a range of machining conditions under which self-excited chatter vibration does not occur at the machining point and generates a stability limit diagram SD1 shown in FIG. 4. The stability limit diagram SD1 shows the relationship between the tool rotation speed and the limit value of the axial depth of cut at which self-excited chatter vibration does not occur. In the following description, the line representing the limit value of the axial depth of cut is referred to as the stability limit line LL. When machining is performed within a stable range R1 below the stability limit line LL, self-excited chatter vibration is suppressed, while when machining is performed within an unstable range R2 above the stability limit line LL, self-excited chatter vibration occurs. In order to generate the stability limit diagram SD1, the recommended machining condition determination unit 125 first models the tool TL and the workpiece WK using the tool information and the workpiece information, derives the relationship between the vibration frequency of the tool TL and the compliance by vibration analysis using the model, and identifies the frequency at which the compliance is maximized. Next, the recommended machining condition determination unit 125 determines a transfer function G(s)=1 / (M×s) that fits the peak shape of the compliance at the identified frequency. 2+C×s+K) is derived by curve fitting processing to identify modal parameters such as the mass M of the tool TL or the workpiece WK, the damping coefficient C, and the spring constant K. Then, the recommended machining condition determination unit 125 uses the identified modal parameters to generate a stability limit diagram SD1 in the same manner as the method for determining a chatter stability limit diagram shown in, for example, the Japan Society of Mechanical Engineers Seminar No. 10-24 - Basic Manufacturing and Machining Course - Learn Through Practice "Fundamentals of Cutting and Chatter Vibration," seminar text, pp. 1-12, held on March 4, 2010.

[0021] In step S130, the recommended machining condition determination unit 125 reads the machine tool information from the memory 102 and identifies a range of machining conditions that will cause forced chatter vibration at the machining point. Forced chatter vibration occurs, for example, when the frequency of the cutting force intermittently applied from the tool TL to the workpiece WK matches the natural frequency of the spindle housing 62. In this embodiment, the machine tool information includes information on the natural frequency of the spindle housing 62, and the recommended machining condition determination unit 125 identifies the tool rotational speed within which the rotational frequency of the tool TL falls within ±10% of the natural frequency of the spindle housing 62 as the range in which forced vibration will occur. Furthermore, the recommended machining condition determination unit 125 identifies the tool rotational speed within which the frequency obtained by dividing the rotational frequency of the tool TL by the number of teeth of the cutting tool BD falls within ±10% of the natural frequency of the spindle housing 62 as the range in which forced chatter vibration will occur. The natural frequency of the spindle housing 62 can be calculated using the results of a hammering test in which the spindle housing 62 is vibrated while the machine tool 11 is stationary.

[0022] In step S140, the recommended machining condition determination unit 125 determines the range of the appropriate rotational speed of the tool TL using the tool information and workpiece information. The tool information includes information on the type of tool TL, information on the outer diameter of the cutting tool BD, and information on the appropriate range of the cutting speed of the cutting tool BD. The cutting speed refers to the peripheral speed of the cutting tool BD, in other words, the speed at which the blade of the cutting tool BD cuts the workpiece WK. The appropriate range of the cutting speed is predetermined by the manufacturer of the cutting tool BD for each combination of the type of cutting tool BD, the material of the cutting tool BD, and the material of the workpiece WK. The appropriate range of the cutting speed is described, for example, in a catalog created by the manufacturer of the cutting tool BD. The recommended machining condition determination unit 125 can calculate the tool rotational speed from the cutting speed using the following formula (1): N = 1000 × V / (π × D) (1) Here, N is the tool rotation speed, π is the ratio of the circumference of a circle to its circumference, D is the outer diameter of the cutting tool BD, and V is the cutting speed. Note that depending on the performance of the machine tool 11, it may not be possible to rotate the tool TL at an appropriate rotation speed. In this case, the recommended machining condition determination unit 125 may exclude from the range of appropriate rotation speeds the range of rotation speeds equal to or higher than the maximum rotation speed of the machine tool 11.

[0023] In step S150, the recommended machining condition determination unit 125 determines recommended machining conditions. In this embodiment, the recommended machining condition determination unit 125 determines a recommended rotational speed for the tool rotational speed. The recommended machining condition determination unit 125 determines a recommended rotational speed within a range obtained by excluding the range in which forced chatter vibration occurs, identified in step S130, from the stable range R1 in which self-excited chatter vibration does not occur, identified in step S120, and within the range of appropriate rotational speeds identified in step S140. Specifically, the recommended machining condition determination unit 125 determines the rotational speed at the peak position of the stability limit line LL within the above range as the recommended rotational speed. In this embodiment, if the stability limit line LL has multiple peaks within the above range, the recommended machining condition determination unit 125 determines the rotational speed at each peak position as the recommended rotational speed, and determines the recommended order of the recommended rotational speeds in descending order of rotational speed.

[0024] In step S150, the recommended machining condition determination unit 125 may determine a recommended feed rate in addition to the recommended rotation rate. The recommended machining condition determination unit 125 can calculate the feed rate using the following formula (2). F = f × Z × N (2) Here, F is the feed rate, f is the feed amount per tooth, Z is the number of teeth of the cutting tool BD, and N is the tool rotation speed. The feed amount per tooth is predetermined by the manufacturer of the cutting tool BD for each combination of the type of cutting tool BD, the material of the cutting tool BD, and the material of the workpiece WK. The feed amount per tooth is listed, for example, in a catalog created by the manufacturer of the cutting tool BD.

[0025] In step S150, the recommended machining condition determination unit 125 may determine a recommended axial depth of cut in addition to the recommended rotation speed. The recommended machining condition determination unit 125 can determine the recommended axial depth of cut using the stability limit diagram SD1.

[0026] In step S160, the recommended machining condition determination unit 125 outputs information representing the recommended machining conditions. In this embodiment, the recommended machining condition determination unit 125 generates an additional stability limit diagram SD2 in which information representing the recommended machining conditions is added to the stability limit diagram SD1, and displays the additional stability limit diagram SD2 on the display device 106. Thereafter, the machining condition determination support unit 120 ends this process. Note that steps S120, S130, and S140 do not have to be executed in this order. For example, step S130 may be executed before step S120 is executed. Alternatively, steps S120, S130, and S140 may be executed simultaneously in parallel.

[0027] FIG. 5 shows an example of an additional stability limit diagram SD2 when the cutting tool BD is a seven-flute end mill and the natural frequency of the spindle housing 62 is 42 Hz. The additional stability limit diagram SD2 shows tool rotational speed ranges R3 and R4 within which forced chatter vibration occurs, indicated by dashed lines. Range R3 is within ±10% of the natural frequency of the spindle housing 62, and range R4 is within ±10% of the frequency obtained by dividing the natural frequency of the spindle housing 62 by the number of teeth of the cutting tool BD. The additional stability limit diagram SD2 also shows marks SB indicating recommended rotational speeds. In this embodiment, the additional stability limit diagram SD2 includes marks SB representing multiple recommended rotational speeds, and each mark SB indicates the recommended ranking of each recommended rotational speed. Since a faster tool rotational speed results in a faster feed rate and shorter machining time, the faster the tool rotational speed, the higher the recommended ranking. Each recommended rotational speed is not included in the ranges R3 and R4 within which forced chatter vibration occurs.

[0028] In the machine tool 11 of the present embodiment described above, when tool information and workpiece information are input, the recommended machining condition determiner 125 of the machining condition determination support unit 120 determines recommended machining conditions within a range that excludes the range of machining conditions that cause forced chatter vibration from the range of machining conditions that do not cause self-excited chatter vibration and within the range of appropriate rotational speeds, and causes the display device 106 to display information representing the recommended machining conditions. Therefore, an operator can determine machining conditions for cutting using the information representing the recommended machining conditions. In particular, in this embodiment, when tool information and workpiece information are input, the recommended machining condition determiner 125 generates an additional stability limit diagram SD2 in which information representing the recommended machining conditions is added to the stability limit diagram SD1, and causes the display device 106 to display the additional stability limit diagram SD2. Therefore, an operator can determine machining conditions using the additional stability limit diagram SD2.

[0029] In this embodiment, the recommended machining condition determination unit 125 generates an additional stability limit diagram SD2 showing a plurality of recommended machining conditions and a recommended ranking of each recommended machining condition, and displays the diagram on the display device 106. This allows the operator to select machining conditions from among the plurality of recommended machining conditions. Furthermore, since the recommended ranking is displayed, even an operator with low skill level can easily determine machining conditions.

[0030] Furthermore, in this embodiment, the recommended machining condition determination unit 125 excludes from the recommended machining conditions a range of ±10% of the tool rotational speed at which, when the tool rotational speed is converted into frequency, the value is the same as the natural frequency of the spindle housing 62. This makes it possible to prevent the tool rotational frequency and the natural frequency of the spindle housing 62 from overlapping, causing the spindle housing 62 to resonate and resulting in forced chatter vibration at the machining point.

[0031] Furthermore, in this embodiment, the recommended machining condition determination unit 125 excludes from the recommended machining conditions a range of ±10% of the tool rotational speed obtained by converting the frequency obtained by dividing the natural frequency of the spindle housing 62 by the number of teeth of the tool TL into a rotational speed. Therefore, it is possible to prevent the spindle housing 62 from resonating due to the integral multiple component of the cutting edge passing frequency overlapping with the natural frequency of the spindle housing 62, thereby preventing forced chatter vibration from occurring at the machining point.

[0032] B. Other Embodiments: (B1) In the above-described embodiment, the recommended machining condition determination unit 125 generates an additional stability limit diagram SD2 representing information on the recommended machining conditions and displays it on the display device 106. In contrast, the recommended machining condition determination unit 125 may not generate an additional stability limit diagram SD2, but may display information representing the recommended machining conditions, for example, in text format, on the display device 106. The recommended machining condition determination unit 125 may output the information representing the recommended machining conditions in audio format using a speaker, rather than displaying it on the display device 106.

[0033] (B2) In the above-described embodiment, the recommended machining condition determination unit 125 may exclude the range in which forced vibration occurs from the recommended machining conditions by setting the limit value of the axial cutting depth in the range in which forced vibration occurs to zero.

[0034] (B3) In the above-described embodiment, the recommended machining condition determination unit 125 excludes from the recommended machining conditions both a range of ±10% of the tool rotational speed in which the tool rotational speed, when converted into a frequency, has the same value as the natural frequency of the spindle housing 62, and a range of ±10% of the tool rotational speed obtained by converting the frequency obtained by dividing the natural frequency of the spindle housing 62 by the number of teeth of the tool TL into a rotational speed. In contrast, the recommended machining condition determination unit 125 does not need to exclude either of the above-described ranges from the recommended machining conditions.

[0035] (B4) In the above-described embodiment, the recommended machining condition determination unit 125 identifies the range in which forced chatter vibration occurs using the natural frequency of the spindle housing 62. Alternatively, the recommended machining condition determination unit 125 may identify the range in which forced chatter vibration occurs using, for example, the natural frequency of a fixing jig that fixes the workpiece WK to the table 40.

[0036] (B5) In the above-described embodiment, the machining condition determination support unit 120 is provided in the control device 100 of the machine tool 11. However, the machining condition determination support unit 120 may be provided on a computer separate from the control device 100. In this case, the computer provided with the machining condition determination support unit 120 may be referred to as a machining condition determination support device.

[0037] (B6) In the above-described embodiment, the machine tool 11 is a vertical machining center. However, the machine tool 11 does not have to be a vertical machining center. The machine tool 11 may be, for example, a horizontal machining center or an NC milling machine.

[0038] The present disclosure is not limited to the above-described embodiments and can be realized in various configurations without departing from the spirit thereof. For example, the technical features in the embodiments corresponding to the technical features in each aspect described in the Summary of the Invention section can be appropriately replaced or combined to solve some or all of the above-described problems or achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted. [Explanation of symbols]

[0039] 11...machine tool, 20...bed, 30...saddle, 40...table, 50...column, 60...spindle device, 62...spindle housing, 65...spindle, 67...spindle motor, 100...control device, 101...CPU, 102...memory, 103...input / output interface, 104...internal bus, 105...input device, 106...display device, 110...NC control unit, 120...machining condition determination support unit, 121...input acceptance unit, 125...recommended condition determination unit, BD...cutting tool, HD...tool holder, SD1...stability limit diagram, SD2...additional stability limit diagram, TL...tool, WK...workpiece

Claims

1. A machining condition determination support device that supports the determination of machining conditions for cutting, an input receiving unit that receives input of tool information including information on the specifications of a tool attached to a machine tool and workpiece information including information on the material of a workpiece to be cut by the tool attached to the machine tool; a storage unit that stores machine tool information including information on the vibration characteristics of the machine tool; a recommended machining condition determination unit that determines recommended machining conditions within a range that excludes a range of machining conditions that cause forced chatter vibrations identified using the machine tool information from a range of machining conditions that do not cause self-excited chatter vibrations due to changes in cutting resistance in the cutting process, and within a range of appropriate rotational speeds for the tool that are predetermined for each combination of the tool information and the workpiece information, and outputs information representing the recommended machining conditions to an output unit; Equipped with the machine tool information includes information on the natural frequency of a spindle housing of the machine tool, The machining condition determination support device, wherein the recommended machining condition determination unit excludes from the recommended machining conditions, as a range of machining conditions in which the forced chatter vibration occurs, a range within ±10% of the rotational speed of the tool that becomes the same value as the natural frequency of the spindle housing when the rotational speed of the tool is converted into a frequency.

2. A machining condition determination support device that supports the determination of machining conditions for cutting, an input receiving unit that receives input of tool information including information on the specifications of a tool attached to a machine tool and workpiece information including information on the material of a workpiece to be cut by the tool attached to the machine tool; a storage unit that stores machine tool information including information on the vibration characteristics of the machine tool; a recommended machining condition determination unit that determines recommended machining conditions within a range that excludes a range of machining conditions that cause forced chatter vibrations identified using the machine tool information from a range of machining conditions that do not cause self-excited chatter vibrations due to changes in cutting resistance in the cutting process, and within a range of appropriate rotational speeds for the tool that are predetermined for each combination of the tool information and the workpiece information, and outputs information representing the recommended machining conditions to an output unit; Equipped with the machine tool information includes information on the natural frequency of a spindle housing of the machine tool, The recommended machining condition determination unit excludes from the recommended machining conditions a range of machining conditions in which the forced chatter vibration occurs, the range being within ±10% of the rotational speed of the tool, the frequency being obtained by dividing the natural frequency of the spindle housing by the number of teeth of the tool and converting the frequency into a rotational speed.

3. 3. The machining condition determination support device according to claim 1, the recommended machining condition determination unit generates an additional stability limit diagram in which the recommended machining conditions are added to a stability limit diagram that represents the relationship between the rotational speed of the tool and a cutting depth at which the self-excited chatter vibration does not occur, and outputs the additional stability limit diagram to the output unit as information representing the recommended machining conditions.

4. 4. The machining condition determination support device according to claim 3, The processing condition determination support device, wherein the recommended processing condition determination unit determines a plurality of the recommended processing conditions and a recommended ranking of the plurality of the recommended processing conditions, and outputs information including the recommended processing conditions and the recommended ranking to the output unit as information representing the recommended processing conditions.

5. A processing condition determination support device according to claim 4, The machining condition determination support device, when determining the recommended order of the plurality of recommended machining conditions, determines the recommended order such that the faster the rotation speed of the tool, the higher the recommended order.

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