JP7347028B2 - Gear processing equipment and gear processing method - Google Patents

Description

The present invention relates to a gear processing device and a gear processing method.

In machine tools, when the relative rotational speed between the cutting tool and the workpiece is increased or the depth of cut is increased, chatter vibration is likely to occur in the workpiece. Therefore, for example, Patent Document 1 describes a technique in which the dynamic strain of the workpiece is determined, and the chatter vibration of the workpiece is determined based on the magnitude of the dynamic strain, and the workpiece is machined. There is. Patent Document 2 describes a technology for machining a workpiece while preventing chatter vibration of the workpiece by rotating the cutting tool at a rotation speed at which the natural vibration of the workpiece and the vibration component of the cutting tool do not resonate. is listed.

Patent Document 3 describes a technique for machining a workpiece while preventing the occurrence of chatter vibration of the workpiece by rotating the workpiece or cutting tool by inertia rotation and relatively feeding the cutting tool and the workpiece. has been done. Patent Document 4 describes a technique for machining a workpiece while preventing chatter vibration of the workpiece by reducing the depth of cut of a cutting tool into the workpiece. However, it is unclear whether each of the above-mentioned techniques is applicable to a gear processing device (gear processing method) that processes a gear on a workpiece by skiving.

The present inventor has discovered a technique (Patent Document 5) for processing a gear on a workpiece by suppressing chatter vibration of the workpiece in a gear processing apparatus (gear processing method) that performs skiving processing. That is, Patent Document 5 discloses that while the rotational speeds of the workpiece spindle (workpiece) and tool spindle (gear cutting tool) are varied and rotated synchronously, the gear cutting tool is moved against the workpiece in the direction of the rotational axis of the workpiece. A technique is described for machining a gear on a workpiece by suppressing chatter vibration of the workpiece by moving the gear relative to the workpiece.

Japanese Patent Application Publication No. 2000-237932 Japanese Patent Application Publication No. 2009-274179 Japanese Unexamined Patent Publication No. 127801/1983 Patent No. 5929065 Japanese Patent Application Publication No. 2018-62056

In the above-mentioned gear processing apparatus, only the rotational speeds of the workpiece spindle and the tool spindle are varied, so the actual cutting depth (cutting length) of the cutting edge of the gear cutting tool is varied. That is, as shown in Fig. 19, when the diameter (cutting edge locus diameter) when the locus of the cutting edge is approximated to a circle (center O) is R, and the depth of cut of the cutting edge is a, the following formula (1 ), the feed per tooth Lz is determined by the feed rate Vt-w (hereinafter simply referred to as feed rate Vt-w) of the gear cutting tool relative to the workpiece in the direction of the rotational axis of the workpiece and the average workpiece spindle rotation. It is expressed by the speed Swa. Note that the feed amount per tooth Lz is the amount by which the gear cutting tool approaches the workpiece per rotation of the workpiece. Then, as shown in the following equation (2), the actual cutting depth ht is expressed by the per-tooth feed amount Lz, the cutting depth a, and the cutting edge locus diameter R.

Since √(a/R·(1−a/R)) in equation (2) is constant (because it does not affect speed fluctuation), the actual depth of cut ht is proportional to the feed amount per tooth Lz. In other words, if the workpiece spindle rotational speed Sw is varied as shown in FIG. 20 while keeping the feed rate Vt-w constant, the fluctuation amplitude of the workpiece spindle rotational speed Sw will change as shown in FIGS. 21 and 22. Inversely proportionally, the feed per tooth Lz changes, and the actual depth of cut ht also changes. For this reason, the tool life tends to be shorter than when the rotational speeds of the workpiece spindle and tool spindle are constant.

An object of the present invention is to provide a gear machining device and a gear machining method that can improve tool life.

A first aspect of the present invention is to move the gear cutting tool relative to the workpiece in the direction of the rotational axis of the workpiece while rotating the workpiece and the gear cutting tool synchronously. A gear processing device for processing gear teeth,
a workpiece spindle rotatably supporting the workpiece;
a rotatable tool spindle on which the gear cutting tool is mounted;
a moving body that movably supports at least one of the workpiece spindle and the tool spindle;
a workpiece spindle rotation speed control section that periodically varies the rotation speed of the workpiece spindle;
a tool spindle rotation speed control section that periodically varies the rotation speed of the tool spindle;
a linear motion control unit that relatively moves the gear cutting tool in the direction of the rotational axis of the workpiece and controls the gear cutting tool at a feed rate that is synchronized with periodic fluctuations in the rotational speed of the workpiece spindle and the tool spindle;
a feed speed correction amount calculation unit that calculates a correction amount of the feed speed based on the inertia force of the moving body;
There is a gear processing device equipped with.
A second aspect of the present invention is to move the gear cutting tool relative to the workpiece in the direction of the rotational axis of the workpiece while rotating the workpiece and the gear cutting tool synchronously. A gear processing device for processing gear teeth,
a workpiece spindle rotatably supporting the workpiece;
a rotatable tool spindle on which the gear cutting tool is mounted;
a first moving body that supports the workpiece spindle in a linearly movable manner; and a second moving body that supports the tool spindle in a linearly movable manner;
a workpiece spindle rotation speed control section that periodically varies the rotation speed of the workpiece spindle;
a tool spindle rotation speed control section that periodically varies the rotation speed of the tool spindle;
a linear motion control unit that relatively moves the gear cutting tool in the direction of the rotational axis of the workpiece and controls the gear cutting tool at a feed rate that is synchronized with periodic fluctuations in the rotational speed of the workpiece spindle and the tool spindle;
Based on the first inertial force of the first moving body and the second inertial force of the second moving body, calculate the correction amount of the linear motion of the first moving body and the correction amount of the linear motion of the second moving body. a feed speed correction amount calculation unit,
There is a gear processing device equipped with the following.
A third aspect of the present invention is to move the gear cutting tool relative to the workpiece in the direction of the rotational axis of the workpiece while rotating the workpiece and the gear cutting tool synchronously. A gear processing device for processing gear teeth,
a workpiece spindle rotatably supporting the workpiece;
a rotatable tool spindle on which the gear cutting tool is mounted;
a workpiece spindle rotation speed control section that periodically varies the rotation speed of the workpiece spindle;
a tool spindle rotation speed control section that periodically varies the rotation speed of the tool spindle;
a linear motion control unit that relatively moves the gear cutting tool in the direction of the rotational axis of the workpiece and controls the gear cutting tool at a feed rate that is synchronized with periodic fluctuations in the rotational speed of the workpiece spindle and the tool spindle;
Correcting the rotational speed of at least one of the workpiece spindle and the tool spindle based on a first moment of inertia of a first rotating body including the workpiece and a second moment of inertia of a second rotating body including the gear cutting tool. a rotational speed correction amount calculation unit that calculates the amount;
There is a gear processing device equipped with.

A fourth aspect of the present invention is that the workpiece spindle that rotatably supports the workpiece and the rotatable tool spindle on which the gear cutting tool is mounted are rotated synchronously, and the teeth are rotated in the direction of the rotation axis of the workpiece. A gear machining method for machining gear teeth on the workpiece by moving a cutting tool relative to the workpiece, the method comprising:
a rotational speed varying step of periodically varying the rotational speed of the workpiece spindle and the tool spindle;
a linear motion control step in which the gear cutting tool is relatively moved in the direction of the rotational axis of the workpiece and controlled at a feed rate that is synchronized with periodic fluctuations in the rotational speed of the workpiece spindle and the tool spindle;
a feed speed correction amount calculation step of calculating a correction amount of the feed speed based on the inertia of a moving body that movably supports at least one of the workpiece spindle and the tool spindle;
There is a gear processing method comprising:
In a fifth aspect of the present invention, the workpiece spindle that rotatably supports the workpiece and the rotatable tool spindle on which the gear cutting tool is mounted are synchronously rotated, while the A gear machining method for machining gear teeth on the workpiece by moving a cutting tool relative to the workpiece, the method comprising:
a rotational speed varying step of periodically varying the rotational speed of the workpiece spindle and the tool spindle;
a linear motion control step in which the gear cutting tool is relatively moved in the direction of the rotational axis of the workpiece and controlled at a feed rate that is synchronized with periodic fluctuations in the rotational speed of the workpiece spindle and the tool spindle;
Based on the first inertial force of the first moving body that supports the workpiece spindle in a linearly movable manner and the second inertia of the second moving body that supports the tool spindle in a linearly movable manner, a feed speed correction amount calculation step of calculating a linear motion correction amount and a linear motion correction amount of the second moving body;
There is a gear processing method comprising:
In a sixth aspect of the present invention, the workpiece spindle that rotatably supports the workpiece and the rotatable tool spindle on which the gear cutting tool is mounted are rotated synchronously, while the A gear machining method for machining gear teeth on the workpiece by moving a cutting tool relative to the workpiece, the method comprising:
a rotational speed varying step of periodically varying the rotational speed of the workpiece spindle and the tool spindle;
a linear motion control step in which the gear cutting tool is relatively moved in the direction of the rotational axis of the workpiece and controlled at a feed rate that is synchronized with periodic fluctuations in the rotational speed of the workpiece spindle and the tool spindle;
Correcting the rotational speed of at least one of the workpiece spindle and the tool spindle based on a first moment of inertia of a first rotating body including the workpiece and a second moment of inertia of a second rotating body including the gear cutting tool. a rotational speed correction amount calculation step of calculating the amount;
There is a gear processing method comprising:

According to the above aspect of the present invention, the rotational speed of the workpiece spindle is varied in synchronization with the rotational speed of the tool spindle, and the feed rate is varied in synchronization with the rotational speed of the tool spindle. Thereby, the actual cutting depth of the cutting edge of the gear cutting tool can be made constant, and the life of the gear cutting tool can be extended.

1 is a perspective view of a gear processing device in an embodiment of the present invention. FIG. 2 is an enlarged partial cross-sectional view of a gear cutting tool when skiving is performed in the gear processing apparatus of FIG. 1. FIG. It is a block diagram of a control device of a first embodiment of a gear processing device. 4 is a flowchart of gear machining processing executed by the control device of FIG. 3. FIG. It is a block diagram of a control device of a second embodiment of a gear processing device. 6 is a flowchart of the latter half of gear machining processing executed by the control device of FIG. 5. FIG. It is a figure which shows the operation|movement of a gear cutting tool and a workpiece when performing skiving processing. It is a graph when the rotational speed of the workpiece spindle controlled by the control device is varied in a sine wave. It is a graph when the rotational speed of the tool spindle controlled by the control device is synchronized with the rotational speed of the workpiece spindle. FIG. 6 is a diagram for explaining stability determination of the tool spindle rotation speed when rotating the tool spindle. 7 is a graph showing fluctuations in rotational speed synchronization error between the workpiece spindle and the tool spindle. FIG. 2 is a diagram showing waviness and tooth trace error occurring in the tooth trace of gear teeth. It is a graph for explaining first, second, and third correction amounts of the rotational speed of the workpiece spindle. 7 is a graph showing fluctuations in the rotational speed synchronization error between the workpiece spindle and the tool spindle after correction using first and second correction amounts. FIG. 7 is a diagram showing waviness and tooth trace error occurring in the tooth trace of a gear tooth after correction using first and second correction amounts. 7 is a graph showing fluctuations in the rotational speed synchronization error between the workpiece spindle and the tool spindle after correction using first, second, and third correction amounts. FIG. 6 is a diagram showing waviness and tooth trace error occurring in the tooth trace of a gear tooth after correction using first, second, and third correction amounts. It is a figure which shows the operation|movement of the gear cutting tool and workpiece at the time of hobbing in a second embodiment. It is a graph which shows another example of the variation of the rotational speed of a gear cutting tool and a workpiece. It is a figure showing the locus of the cutting edge when machining a workpiece with a gear cutting tool. It is a graph showing fluctuations in the rotational speed of the workpiece spindle. It is a graph showing the fluctuation of the feed amount per tooth when the rotation speed of the workpiece main shaft is varied while the feed speed of the gear cutting tool in the direction of the rotational axis of the workpiece with respect to the workpiece is constant. It is a graph showing the variation in the actual depth of cut when the rotational speed of the workpiece spindle is varied while the feed rate of the gear cutting tool in the direction of the rotational axis of the workpiece is constant.

<1. First embodiment>
(1-1. Schematic configuration of gear processing device)
A schematic configuration of a gear processing device according to a first embodiment of the present invention will be described with reference to FIG. As shown in FIG. 1, the gear processing device 1 is a machining center that has three linear axes (X-axis, Y-axis, and Z-axis) and two rotation axes (A-axis and C-axis) that are orthogonal to each other as drive axes. be. The gear processing apparatus 1 mainly includes a bed 10, a column 20, a saddle 30, a tool spindle 40, a table 50, a tilt table 60, a workpiece spindle 70, and a control device 100.

Bed 10 is placed on the floor. A column 20 is provided on the top surface of this bed 10. The column 20 is provided movably in the X-axis direction (horizontal direction) by an X-axis motor 21 housed in the bed 10 and a ball screw 22 connected to the X-axis motor 21. Further, a saddle 30 is provided on the side surface of the column 20.

The saddle 30 is provided movably in the Y-axis direction (vertical direction) by a Y-axis motor 11 (see FIG. 3) housed in the column 20 and a ball screw (not shown) connected to the Y-axis motor 11. The tool spindle 40 is rotatably provided around the Z-axis by a tool spindle motor 41 (see FIG. 3) having an encoder (not shown) housed in the saddle 30. A gear cutting tool 42 (skiving cutter) is attached to the tip of the tool spindle 40, and the gear cutting tool 42 rotates as the tool spindle 40 rotates.

Here, the gear cutting tool 42 will be explained with reference to FIG. As shown in FIG. 2, the gear cutting tool 42 is a skiving cutter having a plurality of cutting edges 42a on its outer peripheral surface, and the end surface of each cutting edge 42a constitutes a rake face having a rake angle γ. The rake surface of each cutting edge 42a may be tapered around the central axis of the gear cutting tool 42, or may be formed into a plane facing in a different direction for each cutting edge 42a.

As shown in FIG. 1, a table 50 is provided on the top surface of the bed 10. The table 50 is provided movably in the Z-axis direction (horizontal direction) by a Z-axis motor 12 (see FIG. 3) housed in the bed 10 and a ball screw (not shown) connected to the Z-axis motor 12. A tilt table support section 61 that supports the tilt table 60 is provided on the upper surface of the table 50. A tilt table 60 is provided on the tilt table support portion 61 so as to be swingable around the A axis (parallel to the X axis).

A workpiece spindle motor 71 having a workpiece spindle 70 and an encoder (not shown) is provided on the bottom surface of the tilt table 60. The workpiece spindle 70 is rotatably provided around a C-axis perpendicular to the A-axis by a workpiece spindle motor 71. A workpiece W is held at the tip of the workpiece spindle 70, and the workpiece W rotates as the workpiece spindle 70 rotates.

(1-2. Configuration of control device)
The control device 100 processes a gear on the workpiece W by skiving. Specifically, as shown in FIG. 7, the control device 100 aligns the rotation axis C of the workpiece W with respect to the rotation axis O of the gear cutting tool 42 by swinging the tilt table 60 around the A axis. and tilt it. The angle of inclination of the rotational axis O of the gear cutting tool 42 with respect to the rotational axis C of the workpiece W is referred to as the intersection angle δ.

The control device 100 then controls the rotational speed St of the tool spindle 40 (gear cutting tool 42) and the rotational speed Sw of the workpiece spindle 70 (workpiece W). Furthermore, the feed rate of the gear cutting tool 42 relative to the workpiece W in the direction of the rotation axis (center axis C) of the workpiece W, that is, in this example, the feed rate Vz of the table 50 (workpiece W) in the Z-axis direction (hereinafter simply , Z-axis feed rate Vz) and the feed rate Vy of the saddle 30 (gear cutting tool 42) in the Y-axis direction (hereinafter simply referred to as Y-axis feed rate Vy), the feed rate Vz+y (hereinafter simply referred to as feed rate Vz+y). ).

The cutting speed St-w is set based on the machining time (cycle time) required for gear machining, the specifications of the gear cutting tool 42, the material of the workpiece W, the helix angle of the gear formed on the workpiece W, etc. be done. That is, the cutting speed St-w is set to the optimum speed, taking into account the machining efficiency during gear machining, the tool life of the gear cutting tool 42, and the like. In skiving processing, as the cutting speed St-w increases, processing efficiency improves, but quality such as surface texture tends to deteriorate.

Here, as shown in FIGS. 8A and 8B, the rotational speed Sw of the workpiece spindle 70 (average workpiece spindle rotational speed Swa) and the rotational speed St of the tool spindle 40 (average workpiece spindle rotational speed Sta) are set to a sine wave. By performing control to vary the speed, the period in which the gear cutting tool 42 contacts the workpiece W becomes irregular. Therefore, the amplification of chatter vibration generated in the workpiece W is suppressed compared to the case where the rotational speeds Sw and St of the workpiece spindle 70 and the tool spindle 40 are constant without fluctuation. As a result, the depth of cut of the gear cutting tool 42 into the workpiece W can be set large. Therefore, it is possible to both improve the surface quality of the processed surface formed on the workpiece W and improve the processing efficiency.

However, as described in the problem to be solved, when only the rotational speeds Sw and St of the workpiece spindle 70 and tool spindle 40 are varied, the actual depth of cut (cutting length) of the cutting edge 42a of the gear cutting tool 42 changes, and the tool life tends to be shorter than when the rotational speeds Sw and St of the workpiece spindle 70 and the tool spindle 40 are constant. Therefore, the control device 100 of this example varies the rotational speed St of the tool spindle 40 and synchronizes the rotational speed Sw of the workpiece spindle 70 with the rotational speed St of the tool spindle 40. Then, by synchronizing the feed rate Vz+y with the rotation speed St of the tool spindle 40 and sending the gear cutting tool 42 in the direction of the rotational axis C of the workpiece W, the actual cutting depth of the cutting edge 42a of the gear cutting tool 42 is adjusted. is kept constant.

The rotational speed St of the tool spindle 40 is expressed by the following equation (3). In addition, in formula (3), Sta is the average rotation speed of the tool spindle 40 (average tool spindle rotation speed), At is the fluctuation amplitude of the tool spindle 40, fh is the fluctuation frequency of rotation fluctuation, and t is time. . The rotational speed Sw of the workpiece spindle 70 is expressed by the following equation (4). Note that Swa in equation (4) is the average rotational speed of the workpiece spindle 70 (average workpiece spindle rotational speed).

Further, the Z-axis feed rate Vz is expressed by the following equation (5). Note that Vza in equation (5) is the average Z-axis feed rate. The Y-axis feed rate Vy is expressed by the following equation (6). Note that Vya in equation (6) is the average Y-axis feed speed.

The specific configuration of this control device 100 will be explained. As shown in FIG. 3, the control device 100 includes a workpiece spindle rotation speed control section 110, a tool spindle rotation speed control section 120, a Y-axis feed speed control section 140 (linear motion control section), and a Z-axis feed speed control section. A control section 150 (direct motion control section) is provided.

The tool spindle rotation speed control section 120 drives and controls the tool spindle motor 41 to vary the rotation speed St of the tool spindle 40. The workpiece spindle rotational speed control section 110 drives and controls the workpiece spindle motor 71 to vary the rotational speed Sw of the workpiece spindle 70 in synchronization with the rotational speed St of the tool spindle 40. The Y-axis feed speed control section 140 and the Z-axis feed speed control section 150 control the drive of the Y-axis motor 11 and the Z-axis motor 12, respectively, and vary the feed speed Vz+y in synchronization with the rotation speed St of the tool spindle 40. , adjust the relative distance between the gear cutting tool 42 and the workpiece W.

According to the gear processing apparatus 1 equipped with the control device 100 of the first embodiment described above, the rotation speed Sw of the workpiece spindle 70 is varied in synchronization with the rotation speed St of the tool spindle 40, and the feed rate Vz+y is varied in synchronization with the rotational speed St of the tool spindle 40. Thereby, the actual cutting depth of the cutting edge 42a of the gear cutting tool 42 can be made constant, and the life of the gear cutting tool 42 can be extended.

(1-3. Gear processing by control device)
Next, gear machining processing (gear machining method) executed by the control device 100 will be described with reference to the drawings. Note that when performing the gear machining process, it is assumed that the workpiece W is held on the workpiece spindle 70 and the gear cutting tool 42 is attached to the tool spindle 40. Further, it is assumed that the inclination angle of the rotational axis O of the gear cutting tool 42 with respect to the rotational axis C of the workpiece W is set to an intersection angle δ, and the gear cutting tool 42 is positioned at the machining start position of the workpiece W. do.

The tool spindle rotation speed control unit 120 causes the tool spindle 40 to idle by varying the rotation speed St of the tool spindle 40 in a sine wave (step S1 in FIG. 4, rotation speed variation step). Then, it is determined whether the rotational speed St of the tool spindle 40 is stable (step S2 in FIG. 4). In this process, as shown in FIG. 9, stability is determined when the average tool spindle rotational speed Swa of the tool spindle 40 is within ±20% of the target center speed.

The tool spindle rotation speed control section 120 inputs a synchronous rotation command to the workpiece spindle rotation speed control section 110 when the rotation speed St of the tool spindle 40 becomes stable. The workpiece spindle rotation speed control section 110 sets the rotation speed Sw of the workpiece spindle 70 so as to synchronize with the rotation speed St of the tool spindle 40 set by the tool spindle rotation speed control section 120. (Step S3 in FIG. 4, rotational speed variation step). Then, the Y-axis feed rate control unit 140 and the Z-axis feed rate control unit 150 control the Z-axis feed rate Vz and the Y-axis feed rate Vy so that the feed rate Vz+y is synchronized with the fluctuation frequency of the rotation speed St of the tool spindle 40. are set respectively and the Z-axis and Y-axis are sent (step S4 in FIG. 4, linear motion control process).

Through the above processing, the gear cutting tool 42 performs continuous gear machining on the workpiece W while meshing with the workpiece W, and processes the tooth flank shape on the workpiece W (step S5 in FIG. 4). Then, it is determined whether the gear machining of the first workpiece W is completed (step S6 in FIG. 4), and when the gear machining of the first workpiece W is completed, it is determined whether or not the gear machining of the next workpiece W is to be performed. Confirm (step S7 in FIG. 4). Then, when there is gear machining for the next workpiece W, the process returns to step S5 and the above-mentioned process is repeated, and when there is no gear machining for the next workpiece W, all the processes are ended.

<2. Second embodiment>
(2-1. Schematic configuration of gear processing device)
The schematic configuration of the gear processing apparatus according to the second embodiment of the present invention is the same as the schematic configuration of the gear processing apparatus according to the first embodiment shown in FIG. 1, so a detailed explanation will be omitted.

(2-2. Configuration of control device)
The control device 100 of the first embodiment varies the rotational speed Sw of the workpiece spindle 70 in synchronization with the rotational speed St of the tool spindle 40. Further, the feed rate Vz+y is varied in synchronization with the rotation speed St of the tool spindle 40. However, the mass of the first rotating body including the workpiece W (the rotating part of the workpiece W and the workpiece spindle 70) and the second rotating body including the gear cutting tool 42 (the rotating part of the gear cutting tool 42 and the tool spindle 40) is not the same as the mass of Therefore, when the rotational speed Sw of the workpiece spindle 70 and the rotational speed St of the tool spindle 40 change, the first moment of inertia of the first rotating body and the second moment of inertia of the second rotating body differ. Due to the difference between the first and second moments of inertia of the first and second rotating bodies, a synchronization error Δθ between the rotational phases of the workpiece spindle 70 and the tool spindle 40 occurs, as shown in FIG. This rotational phase synchronization error Δθ is expressed by the following equation (7). In the formula, θw is the workpiece spindle rotation phase, θt is the tool spindle rotation phase, Zt is the number of tool teeth of the gear cutting tool 42, and Zw is the number of teeth of the gear to be machined on the workpiece W. As a result, as shown in FIG. 11, an undulation of the tooth trace error ε occurs in the tooth trace Gz of the tooth G of the gear to be machined, and there is a possibility that the gear machining accuracy may deteriorate.

Further, a synchronization error may also occur between the feed rate Vz+y and the rotation speed St of the tool spindle 40, and there is a risk that gear machining accuracy may deteriorate in this respect as well. The reason why the synchronization error Δθ between the rotational phases of the workpiece spindle 70 and the tool spindle 40 occurs is due to the mass of the first rotating body including the workpiece W (rotating parts of the workpiece W and the workpiece spindle 70) and the gear cutting tool. The mass of the second rotating body (rotating portion of the gear cutting tool 42 and the tool spindle 40) including the gear cutting tool 42 is not the same. Therefore, when the rotational speed Sw of the workpiece spindle 70 and the rotational speed St of the tool spindle 40 change, the first moment of inertia of the first rotating body and the second moment of inertia of the second rotating body differ.

Further, the reason why a synchronization error occurs between the feed rate Vz+y and the rotation speed St of the tool spindle 40 is that the first moving body including the workpiece W (workpiece W, workpiece spindle 70, table 50, etc.) The mass and the mass of the second moving body including the gear cutting tool 42 (the gear cutting tool 42, the tool main shaft 40, the saddle 30, etc.) are not the same. Therefore, when the feed speed Vz+y and the rotation speed St of the tool spindle 40 change, the first inertial force of the first moving body and the second inertial force of the second moving body are different.

Therefore, the control device 101 of the second embodiment calculates the amount of correction for the rotational speed Sw in the workpiece main shaft 70 based on the first moment of inertia of the first rotating body and the second moment of inertia of the second rotating body. That's what I do. Furthermore, based on the first inertial force of the first moving body and the second inertial force of the second moving body, the feed rate Vz+y, in this example, the correction amount of the Y-axis feed rate Vy and the correction amount of the Z-axis feed rate Vz I am trying to calculate.

The specific configuration of this control device 101 will be explained. As shown in FIG. 3, the control device 101 includes a workpiece spindle rotation speed control section 110, a tool spindle rotation speed control section 120, a rotation speed correction amount calculation section 130, and a Y-axis feed speed control section 140 (linear motion control section), a Z-axis feed speed control section 150 (direct motion control section), and a feed speed correction amount calculation section 160.

The tool spindle rotation speed control section 120 drives and controls the tool spindle motor 41 to vary the rotation speed St (see equation (3)) of the tool spindle 40. The workpiece spindle rotational speed control unit 110 drives and controls the workpiece spindle motor 71 to vary the rotational speed Sw (see equation (4)) of the workpiece spindle 70 in synchronization with the rotational speed St of the tool spindle 40. .

The Y-axis feed rate control unit 140 and the Z-axis feed rate control unit 150 drive and control the Y-axis motor 11 and the Z-axis motor 12, respectively, and set the feed rate Vz+y ((see formulas (5) and (6))) to the tool. The relative distance between the gear cutting tool 42 and the workpiece W is adjusted while being varied in synchronization with the rotational speed St of the main shaft 40.

The rotational speed correction amount calculation unit 130 calculates the rotational speed of the workpiece spindle 70 based on the first moment of inertia of the first rotating body including the workpiece W and the second moment of inertia of the second rotating body including the gear cutting tool 42. Calculate the correction amount of Sw. That is, as shown in FIG. An amplitude correction amount ΔAw-t for finely adjusting the amplitude in periodic fluctuations shown by broken lines in the figure is calculated. By performing this correction, the rotational speed Sw of the workpiece main shaft 70 changes periodically as shown by the dashed line in the figure.

Specifically, the rotational speed correction amount calculation unit 130 calculates the difference Iw between the first moment of inertia of the first rotating body and the second moment of inertia of the second rotating body, which is stored in advance in the rotational speed correction amount calculation unit 130. -t, the fluctuation amplitude At of the rotational speed St of the tool spindle 40, and the fluctuation frequency fh, the amplitude correction amount ΔAw-t of the fluctuation amplitude of the workpiece spindle 70 expressed by the following equation (8) is determined. Note that Cwt in the formula is a constant related to the workpiece W based on the gear cutting tool 42, and is stored in advance in the rotational speed correction amount calculation unit 130. Further, the amplitude correction amount ΔAw-t can also be determined using a formula using similar variables as trigonometric functions.

Further, the rotational speed correction amount calculation unit 130 calculates a minute acceleration/deceleration timing of the first rotating body as a second correction amount included in the correction amount of the rotational speed Sw of the workpiece spindle 70, as shown in FIG. A time shift, that is, an offset time correction amount Pw due to acceleration/deceleration in the first rotating body is calculated. By performing this correction, the rotational speed Sw of the workpiece main shaft 70 changes periodically as shown by the two-dot chain line in the figure.

Specifically, the rotational speed correction amount calculation unit 130 calculates the difference Iw between the first moment of inertia of the first rotating body and the second moment of inertia of the second rotating body, which is stored in advance in the rotational speed correction amount calculation unit 130. -t and the fluctuation frequency fh of the rotational speed St of the tool spindle 40, an offset time correction amount Pw due to acceleration/deceleration in the first rotating body expressed by the following equation (9) is determined. Note that Cw in the formula is a constant related to the first rotating body based on the second rotating body, and is stored in advance in the rotational speed correction amount calculation unit 130. Further, the offset time correction amount Pw can also be determined using a formula using similar variables in trigonometric functions.

Here, when the fluctuation amplitude of the workpiece spindle 70 is corrected by the above-mentioned amplitude correction amount ΔAw-t of the fluctuation amplitude of the workpiece spindle 70 and the offset time correction amount Pw caused by acceleration/deceleration in the first rotary body, the fluctuation amplitude of the workpiece spindle 70 is corrected as shown in FIG. As shown, the rotational phase synchronization error Δθ between the workpiece spindle 70 and the tool spindle 40 is improved more than the rotational phase synchronization error Δθ before correction shown in FIG. However, as shown in FIG. 14, the waviness of the tooth trace error εc in the tooth trace Gz of the tooth G of the gear is slightly improved from the waviness of the tooth trace error ε before correction shown in FIG. 11 (εc<ε). Therefore, the waviness of the tooth trace error is not within the allowable range.

Therefore, as shown in FIG. A slight error, that is, an offset time correction amount ΔPw unique to the device for a time shorter than the rotational speed control period of the first rotating body is calculated.

The offset time correction amount unique to this device is for correcting a deviation in the measurement timing of the encoder, for example, and depends on the control period of the tool spindle rotation speed control section 120 and the workpiece spindle rotation control section 110, but is generally determined by the control command. cannot perform time correction equivalent to that of the rotation speed control section. For this reason, a correction equivalent to a time correction is performed on the rotational phase value of the rotational speed command value. By performing this correction, the rotational speed Sw of the workpiece spindle 70 undergoes periodic fluctuations as shown by the solid line in the figure.

Specifically, the rotational speed correction amount calculation unit 130 calculates the very slight time deviation ΔTw of the workpiece spindle 70 and the fluctuation frequency fh of the rotational speed St of the tool spindle 40, which are stored in advance in the rotational speed correction amount calculation unit 130. Based on the equation (10) below, an offset time correction amount ΔPw unique to the device for a time shorter than the rotational speed control period of the first rotating body is determined.

When the fluctuation amplitude of the workpiece spindle 70 is corrected by the device-specific offset time correction amount ΔPw, which is shorter than the rotational speed control period of the first rotating body, as shown in FIG. 15, the workpiece spindle 70 and the tool spindle 40 The synchronization error Δθ of the rotational phase is slightly larger than the synchronization error Δθ of the rotational phase when corrected by the amplitude correction amount ΔAw−t and the offset time correction amount Pw shown in FIG. 13, but as shown in FIG. As shown, the waviness of the tooth trace error εcc in the tooth trace Gz of the gear tooth G is smaller than the waviness of the tooth trace error εc when corrected by the amplitude correction amount ΔAw−t and the offset time correction amount Pw shown in FIG. (εcc<εc), which falls within the allowable range.

The feed speed correction amount calculation section 160 performs the same processing as the rotation speed correction amount calculation section 130 described above. In other words, the feed speed correction amount calculation unit 160 includes the Z-axis moment of inertia of the ball screw connected to the Z-axis motor 12, which is a substitute value for the first inertial force of the first moving body including the workpiece W, and the gear cutting tool 42. Based on the Y-axis moment of inertia of the ball screw connected to the Y-axis motor 11, which is a substitute value for the second inertia force of the second moving body, the amount of correction for the Z-axis feed rate Vz and the amount of correction for the Y-axis feed rate Vy are determined. Calculate. In other words, the feed speed correction amount calculation unit 160 first calculates the amplitude correction amount for finely adjusting the amplitude of periodic fluctuations in the Z-axis feed speed Vz, as included in the correction amount of the Z-axis feed speed Vz. do.

Specifically, the feed speed correction amount calculation section 160 calculates the difference Iz-y between the Z-axis moment of inertia and the Y-axis moment of inertia, which is stored in advance in the feed speed correction amount calculation section 160, the average Z-axis feed speed Sza, Based on the fluctuation amplitude At (=Ay: Y-axis fluctuation amplitude) of the rotational speed St of the tool spindle 40 and the fluctuation frequency fh, the amplitude correction amount ΔAz-y of the Z-axis fluctuation amplitude is expressed by the following formula (11). seek. Note that Czt in the formula is a constant related to the Z axis based on the gear cutting tool 42, and is stored in advance in the feed rate correction amount calculation unit 160. Further, the amplitude correction amount ΔAz-y can also be determined using a formula using similar variables as trigonometric functions.

Furthermore, the feed speed correction amount calculation unit 160 calculates a minute time difference in the acceleration/deceleration timing of the first moving body, that is, a slight time difference in the acceleration/deceleration timing of the first moving body, as included in the correction amount of the Z-axis feed speed Vz. Calculate the resulting offset time correction amount. This offset time correction amount is determined by measuring the rotational phase of the tool spindle 40 and the Z-axis position by the synchronous fluctuation command when the tool spindle 40 is idling and the Z-axis is idling before machining, and This corresponds to the time shift of the Z axis with respect to the rotational phase (maximum tool spindle rotation speed, minimum tool spindle rotation speed, timing to reach the average tool spindle rotation speed).

Specifically, the feed speed correction amount calculation section 160 calculates the difference Iz-t between the Z-axis moment of inertia and the second moment of inertia of the second rotating body, which is stored in advance in the feed speed correction amount calculation section 160, Based on the average Z-axis feed rate Sza and the fluctuation frequency fh of the rotation speed St of the tool spindle 40, an offset time correction amount Pz due to acceleration/deceleration in the first moving body expressed by the following equation (12) is determined. Note that Cz in the formula is a constant related to the first moving body, and is stored in advance in the feed speed correction amount calculation unit 160. Further, the offset time correction amount Pz can also be determined using a formula using similar variables in trigonometric functions.

Furthermore, the feed speed correction amount calculation unit 160 calculates a very small temporal error in the first moving body, that is, a feed speed control period in the first moving body, as included in the correction amount of the Z-axis feed speed Vz. Calculate the device-specific offset time correction amount for a shorter time. The offset time correction amount unique to this device depends on the control period of the tool spindle rotation speed control section 120 and the workpiece spindle rotation speed control section 110, but generally the control command cannot perform time correction equivalent to the rotation speed control section. For this reason, a correction equivalent to time correction is performed on the feed speed command value.

Specifically, the feed speed correction amount calculation unit 160 calculates the amount based on the very slight time deviation ΔTz of the Z axis and the fluctuation frequency fh of the rotation speed St of the tool spindle 40, which are stored in advance in the feed speed correction amount calculation unit 160. Then, the device-specific offset time correction amount ΔPz for a time shorter than the feed speed control cycle of the first moving body expressed by the following equation (13) is determined.

In addition, the feed speed correction amount calculation unit 160 calculates a minute time difference in the acceleration/deceleration timing of the second moving body, that is, the acceleration/deceleration of the second moving body, as included in the correction amount of the Y-axis feed speed Vy. Calculate the resulting offset time correction amount.

Specifically, the feed speed correction amount calculation section 160 calculates the difference Iy-t between the Y-axis moment of inertia and the second moment of inertia of the second rotating body, which is stored in advance in the feed speed correction amount calculation section 160, and the Y-axis Based on the average Y-axis feed rate Sya and the fluctuation frequency fh of the rotation speed St of the tool spindle 40, an offset time correction amount Py due to acceleration/deceleration in the second moving body expressed by the following equation (14) is determined. Note that Cy in the formula is a constant related to the second moving body, and is stored in advance in the feed speed correction amount calculation unit 160. Further, the offset time correction amount Py can also be determined using a formula using similar variables in trigonometric functions.

Furthermore, the feed speed correction amount calculation unit 160 calculates, as included in the correction amount of the Y-axis feed speed Vy, an extremely small temporal error in the second moving body, that is, the feed speed control period in the second moving body. Calculate the device-specific offset time correction amount for a shorter time. The offset time correction amount unique to this device depends on the control cycles of the tool spindle rotation speed control section 120 and the workpiece spindle rotation speed control section 110, but generally the control command cannot perform time correction equivalent to the rotation speed control section. For this reason, a correction equivalent to time correction is performed on the feed speed command value.

Specifically, the feed speed correction amount calculation unit 160 calculates the amount based on the very slight time deviation ΔTy of the Y axis and the fluctuation frequency fh of the rotation speed St of the tool spindle 40, which are stored in advance in the feed speed correction amount calculation unit 160. Then, the device-specific offset time correction amount ΔPy for a time shorter than the feed speed control period in the first moving body expressed by the following equation (15) is determined.

According to the gear processing apparatus 1 including the control device 101 of the second embodiment described above, in addition to the effects of the first embodiment, it is possible to further suppress the waviness of the tooth trace Gz of the tooth G of the gear to be processed. It is possible to significantly improve the machining accuracy of gears processed in gear machining. The rotational speed Sw of the workpiece spindle 70 is varied in synchronization with the rotational speed St of the tool spindle 40, and the feed rate Vz+y is varied in synchronization with the rotational speed St of the tool spindle 40. Thereby, the actual cutting depth of the cutting edge 42a of the gear cutting tool 42 can be made constant, and the life of the gear cutting tool 42 can be extended.

(2-3. Gear processing by control device)
Next, gear machining processing (gear machining method) executed by the control device 101 will be explained with reference to the drawings. Note that when performing the gear machining process, it is assumed that the workpiece W is held on the workpiece spindle 70 and the gear cutting tool 42 is attached to the tool spindle 40. Further, it is assumed that the inclination angle of the rotational axis O of the gear cutting tool 42 with respect to the rotational axis C of the workpiece W is set to an intersection angle δ, and the gear cutting tool 42 is positioned at the machining start position of the workpiece W. do.

The tool spindle rotational speed control unit 120 causes the tool spindle 40 to idle by varying the rotational speed St of the tool spindle 40 in a sine wave (step S11 in FIG. 6, rotational speed variation step). Then, it is determined whether the rotational speed St of the tool spindle 40 is stable (step S12 in FIG. 6). As shown in FIG. 9, this process is determined to be stable when the average tool spindle rotational speed Sta of the tool spindle 40 is within ±20% of the target center speed.

The tool spindle rotation speed control section 120 inputs a synchronous rotation command to the workpiece spindle rotation speed control section 110 when the rotation speed St of the tool spindle 40 becomes stable. The workpiece spindle rotation speed control section 110 sets the rotation speed Sw of the workpiece spindle 70 so as to synchronize with the rotation speed St of the tool spindle 40 set by the tool spindle rotation speed control section 120. (Step S13 in FIG. 6, rotational speed variation step). Then, the Y-axis feed rate control unit 140 and the Z-axis feed rate control unit 150 control the Z-axis feed rate Vz and the Y-axis feed rate Vy so that the feed rate Vz+y is synchronized with the fluctuation frequency of the rotation speed St of the tool spindle 40. are set respectively, and the Z-axis and Y-axis are idle-fed (step S14 in FIG. 6, linear motion control process).

Then, the rotational speed correction amount calculation unit 130 calculates the rotational speed correction amount of the workpiece spindle 70 (step S15 in FIG. 6). The feed speed correction amount calculation unit 160 calculates the Z-axis feed speed correction amount and the Y-axis feed speed correction amount (step S16 in FIG. 6, feed speed correction amount calculation step). Then, the workpiece spindle rotational speed control unit 110 corrects the rotational speed Sw of the workpiece spindle 70 using the rotational speed correction amount of the workpiece spindle 70 as shown in the following equation (16) (step S17 in FIG. 6). The Z-axis feed rate control unit 150 and the Y-axis feed rate control unit 140 correct the Z-axis feed rate Vz and Y-axis feed rate Vy as shown in the following equation (17) and the following equation (18). and the Y-axis feed rate correction amount (step S18 in FIG. 6).

Through the above process, the gear cutting tool 42 performs continuous gear machining on the workpiece W while meshing with the workpiece W, and processes the tooth flank shape on the workpiece W (step S19 in FIG. 6). Then, it is determined whether the gear machining of the first workpiece W is completed (step S20 in FIG. 6), and when the gear machining of the first workpiece W is completed, it is determined whether or not the gear machining of the next workpiece W is to be performed. Confirm (step S21 in FIG. 6). Then, when there is gear machining for the next workpiece W, the process returns to step S19 and the above-described process is repeated, and when there is no gear machining for the next workpiece W, all processes are ended. Further, in the second embodiment, Az is corrected on the basis of Ay (=At), but each of Az and Ay can also be corrected on the basis of At.

<3. Third embodiment>
Next, a third embodiment will be described with reference to FIG. 17. In the first and second embodiments, a case has been described in which the gear cutting tool 42 is a skiving cutter and the gear processing apparatus 1 performs gear processing by skiving processing. On the other hand, in the third embodiment, a case will be described in which the gear cutting tool 242 is a hob cutter and the gear processing device 1 performs gear processing by hobbing. Note that the same parts as in the first embodiment described above are given the same reference numerals, and their explanations will be omitted.

The gear processing device 1 arranges the gear cutting tool 242 and the workpiece W so that the rotation axis O of the gear cutting tool 242 and the C axis, which is the rotational axis of the workpiece W, intersect. In addition, in FIG. 17, the gear cutting tool 242 and the workpiece W are arranged so that the rotational axis O of the gearing tool 242 and the C axis, which is the rotational axis of the workpiece W, are orthogonal to each other. During gear machining, the gear processing device 1 sends (relatively moves) the gear cutting tool 242 in the Z-axis direction, which is the central axis of the workpiece W, while rotating the workpiece W and the gear cutting tool 242 respectively. By doing so, a gear is machined onto the workpiece W.

In this gear machining, in addition to the effects of the first embodiment, the waviness of the tooth trace Gz of the tooth G of the gear to be machined can be further suppressed, so that the machining accuracy of the gear to be machined can be greatly increased. can. The rotational speed Sw of the workpiece spindle 70 is varied in synchronization with the rotational speed St of the tool spindle 40, and the feed rate Vz+y is varied in synchronization with the rotational speed St of the tool spindle 40. Thereby, the actual cutting depth of the cutting edge 42a of the gear cutting tool 42 can be made constant, and the life of the gear cutting tool 42 can be extended.

<4. Others>
In each of the above embodiments, a case has been described in which the rotational speed Sw of the workpiece spindle 70 is varied in a sine wave, but as shown in FIG. 18, the rotational speed Sw of the workpiece spindle 70 may be varied in a triangular wave. Similarly, the rotational speed Sw of the workpiece spindle 70 may be varied so that the parabola changes in a wavy manner.

Further, in each of the above embodiments, the rotational speed correction amount of the workpiece spindle 70 is calculated, but the rotational speed correction amount of the tool spindle 40 may be calculated. Alternatively, a configuration may be adopted in which the rotational speed correction amounts for both the workpiece spindle 70 and the tool spindle 40 are calculated. In this case, the rotational speed correction amount of the workpiece spindle 70 and the rotational speed correction amount of the tool spindle 40 are calculated at a ratio of 50% to 50%, or the number of teeth of the gear to be machined on the workpiece W and the gear cutting tool 42 are calculated. It is determined by the ratio of the number of blades.

Further, in each of the above embodiments, the gear processing apparatus 1 is configured such that the column 20 is movable in the X-axis direction, but the table 50 may be configured to be movable in the X-axis direction instead of the column 20. . Moreover, although the configuration in which the table 50 is movable in the Z-axis direction has been described, the column 20 may be configured to be movable in the Z-axis direction instead of the table 50. Further, although a horizontal machining center has been described as the gear processing device 1, the present invention is also applicable to a vertical machining center. Further, the present invention is applicable to machine tools in general.

Furthermore, in each of the above embodiments, a case has been described in which each axis is corrected in a machining center capable of machining with two rotary axes (tool spindle 40, workpiece spindle 70) and two linear axes (Z axis, Y axis). Two rotating axes (tool spindle 40, workpiece spindle 70) and one linear axis (e.g. Z-axis), two rotating axes (tool spindle 40, workpiece spindle 70) and three linear axes (Z-axis, Y-axis, The present invention can also be applied to the case where each axis is corrected in a machining center that can perform machining along the X-axis. It is applicable not only to gear processing but also to variable ratio rack and tooth crowning processing.

1: Gear processing device, 40: Tool spindle, 41: Tool spindle motor, 42: Gear cutting tool, 70: Workpiece spindle, 71: Workpiece spindle motor, 100: Control device, 110: Workpiece spindle rotation speed Control section, 120: Tool spindle rotation speed control section, 130: Rotation speed correction amount calculation section, 140: Y-axis feed speed control section, 150: Z-axis feed speed control section, 160: Feed speed correction amount calculation section, W: workpiece

Claims (14)

Gear machining in which gear teeth are machined on the workpiece by moving the gear cutting tool relative to the workpiece in the direction of the rotational axis of the workpiece while rotating the workpiece and the gear cutting tool synchronously. A device,
a workpiece spindle rotatably supporting the workpiece;
a rotatable tool spindle on which the gear cutting tool is mounted;
a moving body that movably supports at least one of the workpiece spindle and the tool spindle;
a workpiece spindle rotation speed control section that periodically varies the rotation speed of the workpiece spindle;
a tool spindle rotation speed control section that periodically varies the rotation speed of the tool spindle;
a linear motion control unit that relatively moves the gear cutting tool in the direction of the rotational axis of the workpiece and controls the gear cutting tool at a feed rate that is synchronized with periodic fluctuations in the rotational speed of the workpiece spindle and the tool spindle;
a feed speed correction amount calculation unit that calculates a correction amount of the feed speed based on the inertia force of the moving body;
A gear processing device equipped with. The gear processing apparatus according to claim 1 , wherein the correction amount of the feed rate includes an amplitude correction amount for periodic fluctuations in the feed rate. The gear processing apparatus according to claim 1 or 2 , wherein the correction amount of the feed rate includes an offset time correction amount due to acceleration/deceleration of the feed rate. The gear processing apparatus according to any one of claims 1 to 3 , wherein the feed speed correction amount calculation unit calculates the correction amount of the feed speed based on a fluctuation frequency of the feed speed. The gear processing device according to any one of claims 1 to 4 , wherein the correction amount of the feed rate includes a device-specific correction amount. The gear processing device according to claim 5 , wherein the device-specific correction amount is calculated based on a fluctuation frequency of the feed rate. Gear machining in which gear teeth are machined on the workpiece by moving the gear cutting tool relative to the workpiece in the direction of the rotational axis of the workpiece while rotating the workpiece and the gear cutting tool synchronously. A device,
a workpiece spindle rotatably supporting the workpiece;
a rotatable tool spindle on which the gear cutting tool is mounted;
a first moving body that supports the workpiece spindle in a linearly movable manner; and a second moving body that supports the tool spindle in a linearly movable manner;
a workpiece spindle rotation speed control section that periodically varies the rotation speed of the workpiece spindle;
a tool spindle rotation speed control section that periodically varies the rotation speed of the tool spindle;
a linear motion control unit that relatively moves the gear cutting tool in the direction of the rotational axis of the workpiece and controls the gear cutting tool at a feed rate that is synchronized with periodic fluctuations in the rotational speed of the workpiece spindle and the tool spindle;
Based on the first inertial force of the first moving body and the second inertial force of the second moving body, calculate the correction amount of the linear motion of the first moving body and the correction amount of the linear motion of the second moving body. a feed speed correction amount calculation unit,
A gear processing device equipped with. The feed rate correction amount calculation unit calculates a linear motion correction amount of the first moving body and a linear motion correction amount of the second moving body based on the difference between the first inertial force and the second inertial force. The gear processing device according to claim 7 , wherein the gear processing device calculates. The gear processing device is configured to control at least one of the workpiece spindle and the tool spindle based on a first moment of inertia of a first rotating body including the workpiece and a second moment of inertia of a second rotating body including the gear cutting tool. The gear processing device according to any one of claims 1 to 8 , further comprising a rotational speed correction amount calculation unit that calculates a rotational speed correction amount for one of the gears. Gear machining in which gear teeth are machined on the workpiece by moving the gear cutting tool relative to the workpiece in the direction of the rotational axis of the workpiece while rotating the workpiece and the gear cutting tool synchronously. A device,
a workpiece spindle rotatably supporting the workpiece;
a rotatable tool spindle on which the gear cutting tool is mounted;
a workpiece spindle rotation speed control section that periodically varies the rotation speed of the workpiece spindle;
a tool spindle rotation speed control section that periodically varies the rotation speed of the tool spindle;
a linear motion control unit that relatively moves the gear cutting tool in the direction of the rotational axis of the workpiece and controls the gear cutting tool at a feed rate that is synchronized with periodic fluctuations in the rotational speed of the workpiece spindle and the tool spindle;
Correcting the rotational speed of at least one of the workpiece spindle and the tool spindle based on a first moment of inertia of a first rotating body including the workpiece and a second moment of inertia of a second rotating body including the gear cutting tool. a rotational speed correction amount calculation unit that calculates the amount;
A gear processing device equipped with. The gear cutting tool is a skiving cutter,
The gear processing device moves the gear cutting tool relative to the workpiece in the direction of the rotational axis of the workpiece, with the rotational axis of the workpiece being inclined with respect to the rotational axis of the gear cutting tool. The gear processing apparatus according to any one of claims 1 to 10, wherein the gear skiving process is performed on the workpiece by skiving the gear. While synchronously rotating a workpiece spindle that rotatably supports the workpiece and a rotatable tool spindle on which the gear cutting tool is attached, the gear cutting tool is moved relative to the workpiece in the direction of the rotational axis of the workpiece. A gear machining method for machining gear teeth on the workpiece by relative movement, the method comprising:
a rotational speed varying step of periodically varying the rotational speed of the workpiece spindle and the tool spindle;
a linear motion control step in which the gear cutting tool is relatively moved in the direction of the rotational axis of the workpiece and controlled at a feed rate that is synchronized with periodic fluctuations in the rotational speed of the workpiece spindle and the tool spindle;
a feed speed correction amount calculation step of calculating a correction amount of the feed speed based on the inertia of a moving body that movably supports at least one of the workpiece spindle and the tool spindle;
A gear processing method comprising: While synchronously rotating a workpiece spindle that rotatably supports the workpiece and a rotatable tool spindle on which the gear cutting tool is attached, the gear cutting tool is moved relative to the workpiece in the direction of the rotational axis of the workpiece. A gear machining method for machining gear teeth on the workpiece by relative movement, the method comprising:
a rotational speed varying step of periodically varying the rotational speed of the workpiece spindle and the tool spindle;
a linear motion control step in which the gear cutting tool is relatively moved in the direction of the rotational axis of the workpiece and controlled at a feed rate that is synchronized with periodic fluctuations in the rotational speed of the workpiece spindle and the tool spindle;
Based on the first inertial force of the first moving body that supports the workpiece spindle in a linearly movable manner and the second inertia of the second moving body that supports the tool spindle in a linearly movable manner, a feed speed correction amount calculation step of calculating a linear motion correction amount and a linear motion correction amount of the second moving body;
A gear processing method comprising: While synchronously rotating a workpiece spindle that rotatably supports the workpiece and a rotatable tool spindle on which the gear cutting tool is attached, the gear cutting tool is moved relative to the workpiece in the direction of the rotational axis of the workpiece. A gear machining method for machining gear teeth on the workpiece by relative movement, the method comprising:
a rotational speed varying step of periodically varying the rotational speed of the workpiece spindle and the tool spindle;
a linear motion control step in which the gear cutting tool is relatively moved in the direction of the rotational axis of the workpiece and controlled at a feed rate that is synchronized with periodic fluctuations in the rotational speed of the workpiece spindle and the tool spindle;
Correcting the rotational speed of at least one of the workpiece spindle and the tool spindle based on a first moment of inertia of a first rotating body including the workpiece and a second moment of inertia of a second rotating body including the gear cutting tool. a rotational speed correction amount calculation step of calculating the amount;
A gear processing method comprising:

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