JP6720543B2 - Gear processing method - Google Patents

Description

The present invention relates to a gear machining method for machining a gear by skiving.

In Patent Document 1, a ring-shaped work is rotated, and a skiving cutter (pinion cutter in the literature) that rotates in synchronization with the work is sent in the tooth trace direction of the tooth portion formed on the work to cut the teeth. A processing form for realizing the above is shown.

As described in Patent Document 1, a workpiece that is processed by rotating a workpiece and a skiving cutter synchronously realizes high-speed processing.

JP 2012-45687 A

As described in Patent Document 1, in the technique of cutting a work with a cutter by a skiving technique to process a gear, the shape of the cutting edge contour of the cutter changes due to wear when the cutter is continuously used. However, as a result, the processing accuracy deteriorates.

To cope with this inconvenience, the rake angle of the cutter is ground with a grindstone, and then the film is removed and recoated for reuse. However, if the grinding is repeatedly used a plurality of times, the tooth profile of the cutter changes, so that machining that deviates from the desired tooth profile is performed, and there is room for improvement.

An object of the present invention is to configure a gear machining method capable of machining a gear with required accuracy while avoiding the influence of a change in the tooth profile of the cutter.

The features of the present invention include an annular work that is rotatably supported around a work axis, and a pinion-shaped cutter that is rotatably supported around a cutter axis.
The work shaft center and the cutter shaft center are misaligned so that a clearance angle is created between the tooth trace direction of the tooth portion formed on the workpiece by the cutter and the tooth trace direction of the cutting edge portion of the cutter. The cutting form is arranged in a positional relationship, the work and the cutter are synchronously rotated, and the cutting mode is such that cutting is performed by relative movement of the work and the cutter in the direction along the tooth trace of the tooth portion formed on the work. Is set,
Every time the cumulative time of cutting by the cutter reaches a predetermined value, the rake face of the cutter is ground, and depending on the number of times of grinding or the cumulative amount of grinding, with respect to the tooth trace direction of the tooth portion formed on the workpiece. Posture of the cutter shaft core so as to incline the tooth trace direction of the cutting edge portion of the cutter in a direction in which the cutting width and tooth profile of the rake face reduced by the grinding are restored in a direction view along the work shaft core. The point is that the adjustment of the axis angle is performed.

When the number of times of grinding or the amount of grinding increases, the tooth profile of the cutter changes due to film removal and recoating or geometrical error. On the other hand, according to the configuration of the present invention, the rake face is ground every time when the integrated time of cutting by the cutter reaches a predetermined value, so that the contour portion of the cutting edge is sharpened and cutting can be performed. Although the tooth profile of the cutting edge changes according to the number of times of grinding or the amount of grinding, the rake decreased by grinding the tooth trace direction of the cutting edge with respect to the tooth trace direction of the tooth part formed on the workpiece. It is possible to correct the tooth profile error of the gear by inclining the cutting width of the surface and the tooth profile in the direction in which the tooth profile is restored along the work axis .
As a result, a gear machining method has been obtained which is capable of machining a gear with required accuracy while avoiding the influence of the change in the tooth profile of the cutter.

The present invention includes a cutting position straight line that passes through the cutting position of the cutting edge portion of the cutter that is deepest into the work and the work axis and is orthogonal to the work axis, and a virtual work axis. Plane is set,
At the same time as the axial angle adjustment, a direction in which the tooth trace of the cutting edge portion is moved toward or away from the work by an offset angle adjustment that changes the angle of the cutter shaft center projected on the virtual plane with respect to the work shaft center. You can change to .

According to this, when the shaft angle is adjusted, the distance between the shafts is also adjusted to change the cutting depth of the cutting edge portion of the cutter with respect to the work to optimize the width of the tooth space. In addition, a virtual plane including a cutting position straight line that passes through the workpiece shaft core and the cutting position that penetrates the workpiece most deeply among the cutting edge portions of the cutter and is orthogonal to the workpiece shaft core, and the workpiece shaft core. is set, the offset angle adjustment to change the angle with respect to the workpiece axis of the cutter axis to be projected on the virtual plane, to approach or separate the tooth trace of the cutting edge to the workpiece, it is formed on the word over click It is also possible to suppress the tooth profile error of the gear.

In particular, the graph of FIG. 15 shows the actual measurement value of the work tooth profile error that occurs when the axial angle adjustment is performed, and the graph of FIG. 16 shows the actual measurement value of the work tooth profile error that occurs when the offset angle adjustment is performed. Indicates the value. That is, when the axial angle is adjusted, as shown in FIG. 15, an error occurs in the tooth profile of the pair of adjacent tooth surfaces. Further, when the offset angle adjustment is performed, an error occurs in the tooth profile of the pair of adjacent tooth surfaces as shown in FIG. 16, but the tendency is opposite to that when the axial angle adjustment is performed. In this way, the characteristics of the tooth profile error of the pair of tooth surfaces have the opposite tendency, so by performing the axial angle adjustment and the offset angle adjustment at the same time, the tooth profile error of the pair of tooth surfaces of the workpiece is canceled out and the tooth profile is adjusted. Can be properly maintained. As a result, the teeth formed on the work can be formed with high accuracy.

The features of the present invention include an annular work that is rotatably supported around a work axis, and a pinion-shaped cutter that is rotatably supported around a cutter axis.
The work shaft center and the cutter shaft center are misaligned so that a clearance angle is created between the tooth trace direction of the tooth portion formed on the workpiece by the cutter and the tooth trace direction of the cutting edge portion of the cutter. The cutting form is arranged in a positional relationship, the work and the cutter are synchronously rotated, and the cutting mode is such that cutting is performed by relative movement of the work and the cutter in the direction along the tooth trace of the tooth portion formed on the work. Is set,
A virtual plane including a cutting position straight line that passes through the cutting position most deeply into the work and the work axis of the cutting edge portion of the cutter and is orthogonal to the work axis, and the work axis is set. ,
The rake face of the cutter is grounded every time the integrated time of cutting by the cutter reaches a predetermined value, and the work of the cutter axis is projected on the virtual plane according to the number of times of grinding or the integrated amount of grinding. The point is to change the direction in which the tooth trace of the cutting edge portion approaches or separates from the work by adjusting the offset angle for changing the angle with respect to the axis .

When the number of times of grinding or the amount of grinding increases, the tooth profile of the cutter changes due to film removal and recoating or geometrical error. On the other hand, according to the configuration of the present invention, the rake face is ground every time when the integrated time of cutting by the cutter reaches a predetermined value, so that the contour portion of the cutting edge is sharpened and cutting can be performed. Further, in correspondence with the grinding times or grinding amount, reduced dimension in the tooth thickness direction of the cutting edge, although the cutting edge is changed in shape to be involved in the cutting of the work, of the cutting edge of the cutter workpiece Offset that changes the angle of the cutter axis with respect to the work axis that is projected on a virtual plane that includes the work axis and the cutting position straight line that passes through the cut position that penetrates deepest into the By adjusting the angle, it becomes possible to move the tooth trace of the cutting edge portion toward or away from the work, and correct the tooth profile error of the gear formed on the work .
As a result, a gear machining method has been obtained which is capable of machining a gear with required accuracy while avoiding the influence of the change in the tooth profile of the cutter.

The present invention, at the same time as the offset angle adjustment, the tooth width direction of the cutting edge portion with respect to the tooth width direction of the tooth portion formed on the workpiece, the cutting width and tooth profile of the rake face reduced by the grinding is Axial angle adjustment is performed to change the posture of the cutter shaft core so that the cutter shaft core is tilted in a direction that restores when viewed along the work shaft core , and the cutting blade portion is changed to a direction that approaches or separates from the work. The distance between the axes may be adjusted.

According to this, when the offset angle is adjusted, the cutting width of the rake face reduced by grinding and the axial angle adjustment that causes the tooth profile to tilt in the direction in which the tooth profile is restored when viewed in the direction along the work axis center, cause the tooth profile error. It becomes possible to correct. Further, by adjusting the distance between the shafts, the cutting depth of the cutting edge portion of the cutter with respect to the work is enlarged and the width of the tooth space is adjusted.

It is a figure which shows the structure of a skiving apparatus. It is sectional drawing which shows arrangement|positioning of a workpiece|work and a cutter. It is a block diagram which shows the control structure of a skiving processing apparatus. It is sectional drawing of the cutting edge part which participates in cutting. It is sectional drawing of the workpiece|work which shows a clearance angle, and a cutting blade part. It is the VI-VI sectional view taken on the line of FIG. It is sectional drawing of a cutting blade part. It is sectional drawing which shows the cutting state of the tooth groove by a cutting blade part. It is sectional drawing which shows the cutting state of the tooth groove by the cutting edge part which ground the rake face. It is sectional drawing which shows the cutting state of the tooth groove by the cutting edge part after axial angle adjustment. It is a flowchart of a cutting routine. It is a perspective view showing a cutting position straight line and a virtual plane. It is a figure which shows an offset angle and a clearance angle. It is a figure which shows an axial angle. It is a graph which shows the tooth flank error accompanying axial angle adjustment. It is a graph which shows the tooth flank error accompanying offset angle adjustment.

Embodiments of the present invention will be described below with reference to the drawings.
[Skiving machine]
As shown in FIGS. 1 and 2, a table 2 that rotatably supports a work 1 and a pinion-shaped cutter 10 that cuts the work 1 are provided, and a cutting control unit C that controls these is provided and the sky is provided. A bing processing device is configured.

This skiving apparatus is a specific example for realizing the gear machining method of the present invention. The cutter 10 is provided with a plurality of gear-shaped cutting blades 11 and is rotatable about a cutter axis X by a shaft holder 4. Supported by. Further, the work 1 is formed in an annular shape, and is supported by the table 2 so as to be rotatable around the work axis Y.

In this skiving apparatus, the work axis Y and the cutter axis X are arranged on the misaligned axis, the cutter 10 is driven and rotated by the cutter motor 10M, and the work 1 is integrated with the table 2 by the table motor 2M. It is driven and rotated.

In the cutter 10, as shown in FIGS. 1, 2 and 4, the tip diameter (diameter of the tip circle) of the rake face 12 on one end side in the direction of the cutter axis X is the base end face 13 on the other end side. It is set to be equal to or larger than the tip diameter (diameter of the tip circle) of. As a result, the tooth thickness at the rake face 12 of the cutting edge portion 11 (thickness in the circumferential direction of the cutting edge portion 11) is set to be equal to or greater than the tooth thickness at the base end surface 13.

In this skiving apparatus, each is arranged so that the tooth trace direction of the tooth portion 1A formed on the work 1 and the tooth trace direction of the cutting edge portion 11 of the cutter 10 are aligned, and as shown in FIG. The positional relationship between the cutter axis X and the workpiece axis Y is set so that an angle of clearance angle α is created between the cutting edge portion 11 and the tooth portion 1A formed on the work 1.

Further, the work 1 is rotated in the rotation direction R while maintaining the positional relationship between the work axis Y and the cutter axis X, and the cutter 10 is synchronously driven so as to be synchronized with this rotation, and the cutter 10 is moved. Cutting (tooth cutting) is realized by shifting 1 (the work 1 supported by the table 2) in the shift direction Z along the work axis Y. In order to enable such a shift, the device is provided with a mechanical guide structure and a shift motor 5 that obtains a shift force.

In this configuration, the cutter 10 is moved along the work axis Y while maintaining the position of the table 2, but instead of this, the table 2 is shifted to perform cutting (tooth cutting). It may be configured as follows.

In particular, when the work 1 and the cutter 10 are driven synchronously, the peripheral speed of the inner circumference of the work 1 and the peripheral speed of the rake face 12 of the cutting blade portion 11 of the cutter 10 (strictly speaking, to the work axis Y) Each velocity is set so as to match the velocity component in the orthogonal direction).

In particular, since the work axis Y and the cutter axis X are arranged on the misaligned axis, when cutting is performed, the velocity vector of the cutting edge portion 11 of the cutter 10 and the velocity vector of the work 1 Are different from each other, and a "slip velocity" is generated between the work 1 and the cutter 10 due to the difference, and cutting is realized by this "slip".

When the cutter 10 is used for cutting (tooth cutting) for a long time while repeating grinding, as shown in FIG. 7, the shape of the cutting edge portion 11 of the rake face 12 of the plurality of cutting edge portions 11 is It changes so as to become dull (the tip of the cutter 10 becomes relatively thin). In FIG. 7, the changed shape of the cutting edge portion 11 is shown by a chain double-dashed line. As a result, the tooth profile of the tooth portion 1A formed on the workpiece 1 also changes with the shape change of the cutting edge portion 11 of the cutter 10 (the thickness of the tooth tip decreases and the thickness of the root increases). .. Further, since the protruding amount of the cutting edge portion 11 is shortened, the tooth length of the tooth portion 1A is also shortened, and a gear having a shape deviating from the desired tooth profile is created.

[Control configuration]
In order to eliminate such an inconvenience and create an appropriate gear, in the skiving processing apparatus, the cutting control unit C includes a table motor 2M, a cutter motor 10M, and a shift motor 5 as shown in FIG. The configuration is such that a control signal is output to the angle adjusting unit 21, the offset angle adjusting unit 22, and the inter-axis distance adjusting unit 23.

Further, the cutting control unit C includes hardware such as a microprocessor and the like, and includes a cutting layout setting unit 15 configured by software, a cutting control unit 16, a grinding counter 17, and a cutting time integration unit 18. ing. The cutting layout setting unit 15, the cutting control unit 16, the grinding counter 17, and the cutting time accumulating unit 18 can be partially configured by hardware such as a logic circuit.

In the cutting control unit C, as shown in FIGS. 6 and 12, the cutting edge portion 11 of the cutter 10 passes through a cutting position P which is a radially protruding position (outer end position of the rake face 12; see FIG. 4), The cutting position straight line Q orthogonal to the work axis Y is set. Incidentally, the cutting position P is a position which is most deeply inserted into the work 1 during cutting. Further, a virtual plane S including the cutting position straight line Q and the work axis Y is set.

By setting the cutting position straight line Q and the virtual plane S in this way, as shown in FIG. 14, the orientation of the cutter axis X with respect to the virtual plane S is the axis angle β as viewed in the direction along the cutting position straight line Q. It is possible to capture. Further, the skiving apparatus has a mechanical structure for adjusting the attitude of the cutter axis X and a mechanical structure for enabling the attitude of the cutter axis X to swing about the cutting position straight line Q, and an axis angle. and an actuator for setting β.

As shown in FIG. 13, in a direction view orthogonal to the virtual plane S, the attitude of the cutter axis X projected on the virtual plane S can be grasped as an offset angle γ. Since the offset angle γ is formed on the same plane as the clearance angle α, when the offset angle γ is adjusted, the clearance angle α is also adjusted. In the control, an angle determined based on the attitude of the cutter axis X when the attitude of the cutter axis X is adjusted along the virtual plane S shown in FIGS. 12 and 13 is referred to as an offset angle γ.

Then, as a configuration for adjusting the offset angle γ (clearance angle α), the skiving apparatus enables the posture of the cutter axis X to swing in the direction along the virtual plane S about the cutting position P. It has a mechanical structure and an actuator that sets the offset angle γ.

The inter-axis distance adjustment unit 23 adjusts the distance between the cutting position P and the position of the work axis Y in the direction along the cutting position straight line Q. As its configuration, the skiving apparatus is provided with a mechanical configuration that enables adjustment of the relative distance between the work 1 and the cutter 10 in the direction of the cutting position straight line Q, and an actuator that realizes this adjustment. There is.

In this skiving apparatus, the adjustment by the axial angle adjusting unit 21 is called the axial angle adjustment, the adjustment by the offset angle adjusting unit 22 is called the offset angle adjustment, and the adjustment by the inter-axis distance adjusting unit 23 is called the inter-axis distance adjustment. ing.

In order to realize these adjustments, the skiving apparatus is provided with a mechanism for setting the relative positional relationship between the work 1 and the cutter 10, as in the machining center. Instead of such a mechanism, for example, a device configured to support the shaft holder 4 by a mechanism similar to the articulated robot arm may be used.

[Control mode]
The cutting control unit C is controlled according to the cutting routine shown in the flowchart of FIG. That is, at the start of cutting, the processing time T (a specific example of the accumulated time) and the number of times of grinding N are acquired, the cutting layout is set according to the number of times of grinding N, and then the cutting layout according to the processing time T is set. Is set and cutting is performed (steps #01 to #04). In this control, the number of times of grinding N is used as the amount of grinding, but an integrated amount of grinding may be used.

In the #02 step, the cutting layout setting unit 15 sets the work 1 and the cutter 10 in a positional relationship capable of cutting in correspondence with the number of grinding times N, and in the #03 step, it corresponds to the machining time T (integrated time). The cutting layout setting unit 15 sets the work 1 and the cutter 10 in a positional relationship capable of cutting. After the cutting layout is set in this way, in step #04, the cutting control unit 16 synchronously drives the table motor 2M and the cutter motor 10M as described above, and controls the shift motor 5 to shift the cutter 10. Shift in direction Z.

The cutting layout is determined by the cutting layout setting unit 15, and the axial angle adjustment by the axial angle adjustment unit 21, the offset angle adjustment by the offset angle adjustment unit 22, and the inter-axis distance adjustment by the inter-axis distance adjustment unit 23 are performed. Are done at the same time. Details of this cutting layout will be described later.

Further, when cutting is performed, the processing time T is calculated by the cutting time integration unit 18 acquiring the usage time TH used by the cutter 10 for the cutting and adding the usage time TH to the processing time T. Will be updated. Then, when the cutting is continued, control is performed to determine (update) the cutting layout based on the processing time T in step #03.

In the execution of this cutting, the control for reflecting the machining time T in the cutting layout (step #03) may not be performed, and the cutting may be continued while maintaining the fixed cutting layout.

When the machining time T exceeds the preset value and the number of grinding times N is less than the set value, the rake face 12 of the cutter 10 is ground and the number of grinding times N is incremented (#05). ~ #07 step).

In step #07, the rake face 12 is ground by a grinder or the like. After this grinding, the control of steps #01 to #05 is executed again.

Further, when it is determined in step #06 that the number of grinding times N exceeds the set value, a message or the like indicating that the cutter 10 needs to be discarded is output and the control ends (#08 step).

In particular, this control determines the cutting layout as follows. That is, when cutting the work 1 with the cutter 10 in the initial state, as shown in FIG. 8, the work 1 is cut by setting the posture of the cutting edge portion 11 of the cutter 10 in the tooth trace direction. The region thus cut becomes the tooth space 1S. Further, as the cutter 10 is continuously used, the rake face 12 of the cutting edge portion 11 is worn as shown by a broken line in FIG. Therefore, the rake face 12 is ground to eliminate the influence of wear.

More specifically, when the grinding of the rake face 12 is repeated, as shown in FIG. 9, the length of the cutting edge portion 11 of the cutter 10 in the tooth width direction (vertical direction in the same figure) is cut by grinding. Not only is shortened, but also due to a decrease in the area involved in cutting in the cutting edge portion 11 (the area when viewed along the work axis Y) and a change in the tooth profile, the width that can be cut (in the circumferential direction) (Width) and the tooth profile of the work 1 change.

Although shown in an exaggerated manner in the same figure, the tooth groove 1S reduced in association with the reduction of the cuttable width (cutting width) is shown by a solid line, and the tooth groove 1S having an appropriate value is shown by a two-dot chain line. There is. Then, when the reduction amount of the cutting width exceeds the set value, the cutting layout is determined as shown in step #02 in order to make the tooth space 1S appropriate. Since the reduction of the cutting width and the change of the tooth profile are proportional to the number of grinding times N, the number of grinding times N is counted for the purpose of determining the timing of updating the axial angle β, the offset angle γ and the inter-axis distance of the cutting layout. It

Further, when setting the shaft angle β in the shaft angle adjustment as one of the cutting layouts, the shaft angle adjustment is performed every time the number of grinding times N reaches the setting in order to compensate for the reduction of the area involved in cutting and the change of the tooth profile. As shown in FIG. 10, the cutting edge portion 11 is inclined at a set angle in the direction indicated by the arrow F about the cutting position straight line Q (position common to the cutting position P), and the cutting edge portion 11 participates in cutting. The area is increased and the tooth profile is optimized. As a result, the cutting width and tooth profile are restored. In this adjustment of the axis angle, it is possible to set the control mode so that the attitude of the cutter 10 is tilted around the axis that is in parallel with the cutting position straight line Q on the virtual plane.

When this axial angle adjustment is performed a plurality of times, a contact state in which one of the cutting blade portions 11 in the tooth thickness direction (the left side surface in the figure) contacts the tooth surface of the facing tooth portion 1A. Reach This contact state is the limit of updating the cutting layout, and the updating of the cutting layout is performed in an area that does not reach the limit. Further, this limit is judged by the number of grinding times N, and when the limit is reached, the cutter 10 is discarded as in step #08.

In particular, as the initial value of the axis angle β, it is basically necessary to perform the layout so that the tooth trace direction of the tooth portion 1A formed on the work 1 and the tooth trace direction of the cutting edge portion 11 of the cutter 10 are parallel to each other. Idea. However, in order to extend the life of the cutter 10 as much as possible (in order to increase the number of grinding times N), as shown by the broken line in FIG. 10, the other side (the right side surface in the figure) of the cutting blade portion 11 in the tooth thickness direction is set. The initial value of the axis angle β is set by setting the posture of the cutting blade portion 11 of the cutter 10 in the tooth trace direction so as to be close to the side surface of the tooth portion 1A facing this.

Further, as one of the cutting layouts, when the inter-axis distance is set by the inter-axis adjustment, the inter-axis distance adjustment is performed in the direction of increasing the cutting depth at the cutting edge portion 11. As a result, cutting is performed on the root side of the cutting edge portion 11 (area near the cutter axis X), and insufficient cutting in the tooth thickness direction is improved.

In particular, when the axial angle is adjusted, the shortage of the cutting amount in the tooth thickness direction and most of the tooth profile error can be compensated, but the cutting error is caused as follows. For this reason, the offset angle adjustment is performed as one of the cutting layouts in order to cancel the cutting error due to the adjustment of the axis angle.

Specifically, the axial angle adjustment causes a cutting error between the one surface and the other surface of the tooth portion 1A formed on the work 1. That is, in the graph of FIG. 15, one of the pair of tooth surfaces of the tooth portion 1A is shown as Left for convenience and the other is shown as Right. As can be seen from the figure, when the axial angle β (see FIG. 14) is inclined from the reference value of 25 degrees which is the design value, the minus error of the Right surface causes the negative error of the Left surface. The error increases as the cutting amount on the Right surface tends to be larger than that on the Left surface.

On the contrary, when the axis angle β is tilted in the direction of decreasing from the reference with reference to the design value of 25 degrees (initial value), the cutting amount of the Right surface is smaller than that of the Left surface. The error tends to be reversed, and the error increases.

On the other hand, even when the offset angle is adjusted, an error is caused between the one surface and the other surface of the tooth portion 1A formed on the work 1. That is, in the graph of FIG. 16, one of the pair of tooth surfaces of the tooth portion 1A is shown as Left for convenience and the other is shown as Right. As can be seen from the figure, when the offset angle γ (see FIG. 13) decreases from the reference point (point shown as “0” in FIG. 16) (the area on the left side in the figure), the Right Although the cutting amount of the surface increases, the cutting amount of the Left surface decreases. The offset angle γ takes an initial value at the reference point.

Such a phenomenon has been confirmed by actual measurement, and each adjustment direction in this control is set so that an error that increases due to the axial angle adjustment is canceled by the offset angle adjustment. Therefore, for example, when the axial angle β is reduced to less than 25 degrees, the offset angle γ is also reduced to offset the error in the cutting amount between the Right surface and the Left surface. As a result, the error that appears in the tooth portion 1A becomes extremely small.

For wear of the tooth tip of the cutting edge portion 11, the axial distance is adjusted in a direction in which the axial distance is increased by an amount corresponding to the amount of wear (the direction in which the tooth tip approaches the work 1), and further the axial angle is adjusted. By also performing the above, insufficient cutting in the tooth height direction of the tooth portion 1A formed on the work 1 and tooth profile error are suppressed.

[Operation/Effect of Embodiment]
As described above, the rake face 12 is ground every time the machining time T during which the cutter 10 is used reaches a predetermined value, whereby the cutting edge portion 11 is maintained in a sharp state and good cutting is realized. Further, when the number of grinding times N reaches the set number of times, by changing the adjustment of the axial angle, the adjustment of the offset angle and the adjustment of the distance between the axes, the cutting edge portion 11 of the cutter 10 changes the shape of the cutting edge involved in the cutting. It is possible to virtually change and create the tooth portion 1A having a required shape.

In addition, the axial angle adjustment corrects the tooth thickness and the tooth profile in the circumferential direction of the work 1, and the offset angle adjustment can eliminate the difference between the left and right tooth profiles caused by the axial angle adjustment. The formation of the portion 1A is realized.

Compared with, for example, grinding the tooth groove of the cutting edge portion 11 of the cutter 10 from such a cutting form, the grinding becomes easier and the cost can be significantly reduced, and as a result, the processing cost of the work 1 can be reduced. To do.

[Another embodiment]
The present invention may be configured as follows in addition to the above-described embodiment (those having the same functions as those in the embodiment are given the same numbers and reference numerals as those in the embodiment).

(A) When changing the cutting layout, the control mode may be set so that the axis angle β and the distance between the axes are changed and the offset angle γ is maintained. Such control causes an error in the tooth portion 1A formed on the work 1. However, when the amount of change in the axis angle β is small, the error is also small and practically no problem.

(B) When the cutting layout is changed, the axis angle β and the offset angle γ may be changed and the control mode may be set so that the adjustment of the inter-axis distance is not performed. Even with such control, an error is caused in the tooth portion 1A formed on the work 1. However, when the amount of change in the axial angle β is small, the error is also small and there is no practical problem.

(C) When changing the cutting layout, the offset angle γ and the inter-axis distance may be changed, and the control mode may be set so that the axis angle β is not adjusted. Even if the control is performed in this way, an error is caused in the tooth portion 1A formed on the work 1. However, when the change amount of the offset angle γ is small, the error is also small and there is no practical problem.

INDUSTRIAL APPLICABILITY The present invention can be used for a gear machining method by skiving.

1 Workpiece 1A Teeth 10 Cutter 11 Cutting edge 12 Rake face 13 Base face T Integrated time (machining time)
X Cutter axis Y Work axis axis α Clearance angle

Claims (4)

An annular work that is rotatably supported around the work shaft center, and a pinion-shaped cutter that is rotatably supported around the cutter shaft center are provided.
The work shaft center and the cutter shaft center are misaligned so that a clearance angle is created between the tooth trace direction of the tooth portion formed on the workpiece by the cutter and the tooth trace direction of the cutting edge portion of the cutter. The cutting form is arranged in a positional relationship, the work and the cutter are synchronously rotated, and the cutting mode is such that cutting is performed by relative movement of the work and the cutter in the direction along the tooth trace of the tooth portion formed on the work. Is set,
Every time the cumulative time of cutting by the cutter reaches a predetermined value, the rake face of the cutter is ground, and depending on the number of times of grinding or the cumulative amount of grinding, with respect to the tooth trace direction of the tooth portion formed on the workpiece. Posture of the cutter shaft core so as to incline the tooth trace direction of the cutting edge portion of the cutter in a direction in which the cutting width and tooth profile of the rake face reduced by the grinding are restored in a direction view along the work shaft core. A gear machining method in which the shaft angle is adjusted to change. A virtual plane including a cutting position straight line that passes through the cutting position most deeply into the work and the work axis of the cutting edge portion of the cutter and is orthogonal to the work axis, and the work axis is set. ,
At the same time as the adjustment of the axial angle, a direction in which the tooth trace of the cutting edge portion is moved toward or away from the work by an offset angle adjustment that changes the angle of the cutter axis projected on the virtual plane with respect to the work axis. The method for machining a gear according to claim 1, wherein the method is changed to . An annular work that is rotatably supported around the work shaft center, and a pinion-shaped cutter that is rotatably supported around the cutter shaft center are provided.
The work shaft center and the cutter shaft center are misaligned so that a clearance angle is created between the tooth trace direction of the tooth portion formed on the workpiece by the cutter and the tooth trace direction of the cutting edge portion of the cutter. The cutting form is arranged in a positional relationship, the work and the cutter are synchronously rotated, and the cutting mode is such that cutting is performed by relative movement of the work and the cutter in the direction along the tooth trace of the tooth portion formed on the work. Is set,
A virtual plane including a cutting position straight line that passes through the cutting position most deeply into the work and the work axis of the cutting edge portion of the cutter and is orthogonal to the work axis, and the work axis is set. ,
The rake face of the cutter is grounded every time the integrated time of cutting by the cutter reaches a predetermined value, and the work of the cutter axis is projected on the virtual plane according to the number of times of grinding or the integrated amount of grinding. A gear machining method for changing the direction in which the tooth trace of the cutting edge portion approaches or separates from the work by adjusting an offset angle that changes an angle with respect to the axis . Simultaneously with the offset angle adjustment, the tooth width direction of the cutting edge portion with respect to the tooth width direction of the tooth portion formed on the work, the cutting width and tooth profile of the rake face reduced by the grinding are the work axis. The adjustment of the axial angle for changing the attitude of the cutter shaft core so as to incline in the direction of restoration along the axial distance adjustment for changing the cutting edge portion in the direction toward or away from the workpiece. The gear machining method according to claim 3, wherein

Images