JP6394156B2 - Gear machining method - Google Patents

Description

  The present invention relates to a gear machining method, and more particularly, to a technique for producing a gear having a good tooth surface by cutting.

  As a gear machining method, in Patent Document 1, when gear cutting is performed on a workpiece (pinion blank in the document) where both ends of the gear cutting portion are tapered surfaces, a waste washer that is in close contact with the tapered surface is pressed and fixed to the workpiece. A technique for cutting the washer and the workpiece together is shown.

  This Patent Document 1 is intended for gear processing by a hobbing machine, and by using a washer on the end face, the impact at the time of cutting is reduced, there is no occurrence of sagging, and no burr is produced on the end face. Is described.

  Patent Document 2 discloses a technique in which a corner portion of a workpiece is chamfered to reduce a load acting on a cutting blade during cutting by a cutter. In particular, [another embodiment] of Patent Document 2 shows that the initial movement direction of the cutter is set to an oblique direction (relative to the rotation axis), and then the cutting is performed in a form of moving parallel to the rotation axis. A cutting form is described in which the cutter is moved in an oblique direction in the direction away from the workpiece.

  This Patent Document 2 describes that the cutting load is reduced by suppressing the phenomenon that the cutter escapes in the direction opposite to the rotation direction due to the reaction force received from the workpiece during cutting.

JP 2008-30162 A JP 2012-45687 A

  In the process of creating a tooth portion by cutting with a pinion-shaped cutter, when the cutter is pulled out from the workpiece, there is a case where a part of the workpiece becomes a small piece and burrs are generated. For this inconvenience, the technique disclosed in Patent Document 1 is effective in suppressing burrs. Also, the technique disclosed in Patent Document 2 can suppress burrs.

  In the skiving technology shown in Patent Document 2, the rotation axis of the workpiece and the rotation axis of the cutter are arranged on the axis, and cutting is performed by “slip” generated by the rotary motion of the cutter and the workpiece. Therefore, smooth and high-speed cutting is possible as compared with other processing methods in which the cutter is reciprocated for cutting.

  In the skiving process, the cutter may be vibrated at the start and end of the cutting process, resulting in an inconvenience that an error occurs in the tooth gap shape. Among the actual cutting areas that function to form tooth gaps in the multiple cutting edges that make up the cutter, this phenomenon is referred to as the leading end of the rotation downstream (leading side) and the trailing upstream of the rotation. This can be explained by referring to the side.

  In other words, when cutting is continued, the leading side and trailing side of the cutting edge are in close contact with the tooth gap while being involved in cutting, and an approximately equal load acts on the leading side and trailing side of the cutting edge. Balances and does not cause vibration.

In skiving, the workpiece rotation axis and the cutter rotation axis are arranged on the axis, so the leading side comes into contact with the workpiece more strongly than the trailing side at the start of cutting and acts on the cutter. Load may become unbalanced and cause vibration.
Similarly, when the cutting edge part comes out of the work at the end of cutting, the leading side comes out of the work first, and the trailing side comes out of the work with a delay, so the load acting on the cutter becomes unbalanced and causes vibration. It will be.

  Such vibration is thought to be due to the fact that the cutter is supported in a cantilevered form and easily vibrates. When the cutter vibrates, the tooth surface shape formed on the workpiece deviates from the desired shape. It was inconvenient.

  Furthermore, when manufacturing gears, it is important to efficiently process a plurality of workpieces, and it is also desired to efficiently process a plurality of gears.

  An object of the present invention is to constitute a machining method capable of efficiently machining a plurality of gears having good tooth surfaces.

A feature of the present invention is that a first clamping step of holding a plurality of workpieces stacked and held along the workpiece axis,
The workpiece is moved upstream by the cutter by a first operation in which the cutter moves along the workpiece axis while the plurality of workpieces held in the first clamping step and the pinion-shaped cutter rotate synchronously. At least by the second operation in which the cutter is separated from the lowermost workpiece before passing through the lowermost workpiece arranged at the most downstream position in the cutting direction among the plurality of workpieces. A first cutting step in which an incomplete tooth gap is formed in the lowermost workpiece;
After the first cutting step, a determination step for determining whether or not the new workpiece used in the next cutting step is a final lot is performed,
If it is determined in the determination step that the new workpiece is not the final lot,
And unfinished workpiece in a state where the opening of the incomplete tooth grooves formed in the first cutting step is opened to the upstream side of the cutting direction, the unfinished workpiece positioned under flow side of the cutting direction than A second clamping step of holding the at least one new workpiece to be overlapped and held along the workpiece axis ;
The first operation is performed such that the incomplete tooth gap of the unfinished workpiece is cut in a state in which the plurality of workpieces and the pinion-shaped cutter that are overlapped in the second clamping step are synchronously driven and rotated. Subsequently, a second cutting step of obtaining a new incomplete workpiece in which another incomplete tooth gap is formed in at least the lowermost workpiece among the new workpieces by performing the second operation ,
Is done,
If it is determined in the determination step that the new workpiece is the final lot,
An incomplete work in a state in which the opening of the incomplete tooth gap formed in the first cutting step is opened to the upstream side in the cutting direction, and disposed downstream of the incomplete work in the cutting direction. A third clamping step of holding the at least one new workpiece overlapped along the workpiece axis;
The first operation is performed such that the incomplete tooth gap of the unfinished workpiece is cut in a state in which the plurality of workpieces and the pinion-shaped cutter that are overlapped in the third clamping step are synchronously driven and rotated. A third cutting step in which the workpiece is cut by continuously performing the first operation until it passes through all new workpieces;
Is in the point where is performed .

According to this processing method, when a plurality of workpieces are cut with a cutter in the first cutting step after the first clamping step, the end face is completely processed by linear cutting in which the cutter moves along the workpiece axis. A good tooth surface required for the plurality of workpieces is created, and burrs are not formed on the workpieces. Further, the remaining work is an incomplete work in which an incomplete tooth gap is formed. The incomplete workpiece is superposed on at least one new workpiece by the second clamping step, and is cut in the second cutting step, whereby a good tooth surface is formed as the completed workpiece.
In particular, in this processing method, since a plurality of workpieces are overlapped and cut with a cutter, a plurality of gears can be manufactured all at once, and the processing efficiency can be increased. Furthermore, since the washer shown in Patent Document 1 is not cut, it is possible to extend the life of the cutter as compared with the structure of Patent Document 1.
Therefore, a machining method has been constructed that can improve the yield of workpieces and efficiently machine a plurality of gears having good tooth surfaces.
Another feature of the present invention is that the leading workpiece in which the leading tooth groove is formed by cutting at the leading position in the first cutting step is more in the cutting direction than the new workpiece in the third clamping step. It is located at the downstream side.
Another feature of the present invention is that, in the first cutting step, cutting is started by bringing the cutter closer to the workpiece from a direction inclined with respect to the workpiece axis, and then the first operation is performed. The leading incomplete work in which the leading incomplete tooth groove is formed on the upstream side in the cutting direction is formed by
In the third clamping step, the leading unfinished workpiece is disposed downstream of the new workpiece in the cutting direction.

Another feature of the present invention is that a plurality of the workpieces include a positioning unit that determines a posture centered on the workpiece axis, and the positions of the plurality of workpieces are determined by the positioning unit in the second clamping step. In the point.

  According to this, even when there are a plurality of unfinished workpieces in the second clamping step, the plurality of workpieces are held in the fixed position around the workpiece axis by the positioning portion in the second cutting step. The desired tooth gap can be formed for a plurality of unfinished workpieces.

Another feature of the present invention is that, in the first cutting step , the second cutting step , and the third cutting step, the cutter is arranged such that a cutter axis is different from the workpiece axis of the plurality of workpieces. And is performed by a skiving machine in which the plurality of workpieces and the cutter move relative to each other along the tooth trace direction of the tooth profile formed on the workpiece in a state in which the plurality of workpieces and the cutter are synchronously driven. It is in.

According to this, skiving is performed in the first cutting step , the second cutting step , and the third cutting step , so that, for example, high-speed processing is possible compared with processing on a hobbing machine. Become.

It is a figure which shows the structure of a skiving processing apparatus. It is sectional drawing of a skiving processing apparatus. It is a figure which shows typically the cutting process by a cutter. It is a disassembled perspective view of a clamp unit. It is a figure which shows the balance state at the time of the cutting of the workpiece | work with a cutter. It is a flowchart which shows the process of gear processing. It is sectional drawing which shows the state which cuts a some workpiece | work with a cutter continuously. It is sectional drawing which shows the modification of the process of gear processing. It is a perspective view which shows the positioning part of another embodiment (a). It is sectional drawing of the positioning part of another embodiment (a). It is sectional drawing which shows the 1st cutting process and 3rd clamping process of another embodiment (b).

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Skiving machine]
As shown in FIG.1 and FIG.2, the table 2 which rotatably supports the some workpiece | work 1 hold | maintained by the crimping | compression-bonding state to the clamp unit C, and the pinion-shaped cutter 10 which cuts the some workpiece | work 1 are provided. Skiving machine is configured.

  This skiving machine is a specific configuration that realizes the gear machining method of the present invention. The table 2 includes a plurality of chucks 3 that hold a clamp unit C, and a work shaft with respect to the shift frame 5 of the cutting operation mechanism M. It is supported so as to be rotatable about the core T. The table 2 has a bottom wall 2A and a cylindrical side wall 2B, and an opening 2C for discharging cutting waste (chip) is formed in the side wall 2B.

  In this embodiment, since the axes of the plurality of workpieces 1 are aligned on the workpiece axis T and the coaxial axis, the unique axis of the workpiece 1 is also shown as the workpiece axis T.

  The cutter 10 is configured in a helical gear type having a plurality of cutting edge portions 10 </ b> A, and is supported by a shaft holder 11 so as to be rotatable around the cutter axis S. As shown in FIG. 3, in this skiving processing apparatus, the workpiece axis T and the cutter axis S are arranged on the offset axis, and the cutter 10 is driven and rotated by a cutter motor 10M.

  The reason why the workpiece axis T and the cutter axis S are arranged on the axis axis is different from each other in that the cutting direction of the cutting edge portion 10A of the cutter 10 is the inner circumference of the workpiece 1 when viewed in a direction perpendicular to the workpiece axis T. It is for setting in parallel with the tooth trace direction of the tooth | gear part formed in this. In particular, in this arrangement, the relative posture is set so that the upper side (shaft holder side) of the cutting edge portion 10A of the cutter 10 is slightly separated from the workpiece 1.

  This skiving apparatus may be provided with a relative angle setting unit for arbitrarily setting the misalignment posture between the workpiece axis T and the cutter axis S. The relative angle setting unit may be a manual operation type or a drive operation type using an electric motor.

  The cutting operation mechanism M includes a shift frame 5 that supports the table 2 and a slide frame 6 that supports the shift frame 5. The shift frame 5 includes a table motor 2M that drives and rotates the table 2. The shift frame 5 is supported so as to be reciprocally movable in the direction along the workpiece axis T with respect to the slide frame 6, and the slide frame 6 includes a shift motor 5 </ b> M that realizes the reciprocal movement.

  The slide frame 6 is supported by the frame of the skiving apparatus so as to be reciprocally movable in two directions orthogonal to each other on a virtual plane in a posture orthogonal to the workpiece axis T. A frame of the skiving apparatus is provided with a first slide motor 6Ma and a second slide motor 6Mb that realize reciprocal movement in these two directions.

  The cutting operation mechanism M assumes a screw feed type as a shift operation by the shift motor 5M and an operation by the first slide motor 6Ma and the second slide motor 6Mb. However, the cutting operation mechanism M may be a combination of a rack gear and a pinion gear. A configuration using a belt may also be used.

  A synchronous motor such as a stepping motor is used for the table motor 2M, the cutter motor 10M, and the shift motor 5M. The first slide motor 6Ma and the second slide motor 6Mb can be controlled independently. This skiving apparatus includes a control unit D that drives these motors.

  In this skiving processing apparatus, the workpiece 1 in which the incomplete tooth groove 1Su (see FIG. 7) is formed is also processed, and the incomplete teeth of the workpiece 1 held in the clamp unit C with respect to the table 2 are processed. A tooth gap sensor 18 capable of optically detecting the groove 1Su is provided. A specific configuration of the tooth gap sensor 18 is assumed to have an optical lens and an image sensor, and the position of the tooth gap can be recognized by processing image data acquired by the image sensor.

  As the tooth gap sensor 18, a contact type sensor that detects the position of the incomplete tooth groove 1Su by bringing a thin plate-like detection body into contact with the inner periphery of the work 1, or a work based on the workpiece axis T. A non-contact type distance sensor that detects the position of the incomplete tooth gap 1Su by measuring the distance to the inner surface can also be used.

〔Controller unit〕
The control unit D obtains information from the keyboard 19 in addition to information from the tooth gap sensor 18, outputs information to the monitor 20, and outputs control information to the plurality of motors described above. The control unit D includes an information processing unit such as a microprocessor or a DSP (digital signal positioner), and includes a synchronous rotation control unit 21, a cutting control unit 22, a phase setting unit 23, and a process set configured by software. Part 24.

  The synchronous rotation control unit 21 realizes synchronous driving rotation of the table 2 and the cutter 10 by the control of the table motor 2M and the cutter motor 10M.

  The cutting control unit 22 sets the cutting depth of the tooth gap 1S formed in the workpiece 1 by determining the position of the cutter 10 with respect to the table 2 under the control of the first slide motor 6Ma and the second slide motor 6Mb. By controlling the shift motor 5M, the table 2 is moved in the tooth trace direction (the direction along the tooth gap 1S) of the workpiece 1 to realize cutting.

  The cutting control unit 22 includes a first operation module 22A and a second operation module 22B. The first operation module 22A realizes a first operation of performing linear cutting by moving the table 2 along the workpiece axis T under the control of the shift motor 5M. Further, the second operation module 22B operates the cutter 1 by controlling at least one of the first slide motor 6Ma and the second slide motor 6Mb in a state where movement in the direction along the workpiece axis T is stopped. The second operation of separating the 10 cutting positions from the work inner surface is realized.

  When the phase setting unit 23 starts the second cutting process (# 05) or the third cutting process (# 07) shown in FIG. 6, the tooth gap sensor 18 detects the position of the incomplete tooth gap 1Su, and the cutter Control is performed to match the ten cutting edge portions 10A with the incomplete tooth gap 1Su.

  Before the start of cutting, the process setting unit 24 is any of a first cutting process (# 02), a second cutting process (# 05), and a third cutting process (# 07), which will be described later. Is provided to the cutting control unit 22, and information for recognizing the process is set by the operator operating the keyboard 19. When the operator operates the keyboard 19, necessary information is displayed on the monitor 20, and the process can be grasped.

  Note that at least one of the synchronous rotation control unit 21, the cutting control unit 22, the phase setting unit 23, and the process setting unit 24 may be configured by hardware such as a logic IC. You may comprise by the combination with wear.

[Clamp unit]
As shown in FIGS. 2 and 4, the clamp unit C includes a cylindrical clamp body 15 and a clamp nut 16 that is screwed into the clamp body 15.

  The clamp body 15 has a cylindrical cylindrical portion 15A into which a plurality of workpieces are fitted without gaps, and a male screw portion 15B is formed on the outer periphery on the upper opening side. A ring-shaped holding portion 15C that protrudes inward is formed at the bottom opening of the clamp body 15, and a posture regulating portion 15D that protrudes parallel to the axial center of the cylindrical portion 15A is formed at the inner surface.

  The clamp nut 16 has a ring-shaped portion 16A having a ring shape as a whole, and a female screw portion 16B is formed on the inner periphery on the lower opening side. A ring-shaped pressing portion 16C protruding inward is formed in the lower opening, and a nut portion 16D is formed on the outer periphery.

  A recess 1 </ b> A (an example of a positioning portion) in which the inner periphery posture regulating portion 15 </ b> D of the clamp body 15 is fitted is formed on the outer periphery of the work 1. From this configuration, a plurality of workpieces 1 are overlapped and fitted into the cylindrical portion 15A of the clamp body 15, and the female screw portion 16B of the clamp nut 16 is screwed into the male screw portion 15B of the clamp main body 15 to be tightened. The workpiece 1 is held in a state of being overlapped in a crimped state between the holding portion 15C and the pressing portion 16C.

  In particular, it is assumed that a plurality of workpieces 1 or a plurality of workpieces 1 and unfinished workpieces 1u are overlapped and held with respect to the clamp unit C. The operator performs a tightening operation using a tool such as a spanner.

[Outline of skiving process]
As described above, the workpiece axis T and the cutter axis S are disposed on the axis axis so that the cutter 10 can be cut in a direction perpendicular to the workpiece axis T as shown in FIG. The blade stripe direction of the blade portion 10A and the tooth stripe direction of the gear formed on the workpiece 1 (direction parallel to the workpiece axis T) are parallel.

  In such a positional relationship, the peripheral speed of the inner periphery of the workpiece 1 and the speed of the cutting edge portion 10A of the cutter 10 are synchronously driven and rotated so that the workpiece 1 is moved in the direction along the workpiece axis T. Thus, cutting of the inner peripheral surface of the workpiece 1 by the cutting edge portion 10A of the cutter 10 is realized.

  Specifically, as shown in FIGS. 2 and 3, the workpiece 1 is rotated in the main rotation direction Rt, and the cutter 10 is rotated in the sub rotation direction Rs. Each speed is set at a constant speed in the main rotation direction Rt at the contact portion between the workpiece 1 and the cutter 10, and the cutting edge of the cutter 10 is moved by moving the table 2 in the upward direction while rotating synchronously in this way. The part 10A moves relative to the work 1 from above to below (this direction is the cutting direction), and the cutting by the cutting edge part 10A is performed.

  In particular, during skiving, when the workpiece 1 and the cutter 10 are synchronously driven and rotated, the speed vector (the direction of S1) of the cutting edge portion 10A of the cutter 10 and the velocity vector of the workpiece 1 (also the direction of R1) are Different. The difference between the velocity vectors creates a relative displacement between the workpiece 1 and the cutter 10 at a “sliding velocity” along the tooth trace direction (a direction coinciding with the cutting direction). In this skiving apparatus, the cutting of the workpiece 1 is enabled by sliding the cutting edge portion 10A with respect to the workpiece 1 in the direction of the tooth trace at the “sliding speed”.

  In this embodiment, an internal spur gear is formed with respect to the inner periphery of the workpiece 1, but the machining mode can be set so that the internal tooth forms a helical gear. When processing a helical gear, while rotating the cutter 10 synchronously with the workpiece 1, a differential that gradually shifts the relative phase between the cutter 10 and the workpiece 1 is given, and the cutter 10 is used as the axis of the workpiece 1. It is also possible to perform processing by moving in the direction along.

[Cutter vibration]
In particular, in this skiving process, since the workpiece axis T and the cutter axis S are arranged on the offset axis, the leading side of the cutting edge portion 10A of the cutter 10 is placed on the trailing side at the start of machining. Contact the work 1 more strongly. As a result, the load acting on the cutter 10 becomes unbalanced, and the cutter 10 may vibrate.

  Further, when the tip of the cutting edge portion 10A of the cutter 10 comes out of the workpiece 1 at the end of processing, the load acting on the trailing side is greatly reduced and the load acts only on the leading side, so the load becomes unbalanced, and the cutter 10 Sometimes vibrated. As described above, when the cutter 10 vibrates, an error occurs in the tooth gap formed in the workpiece 1, and the tooth surface shape may deviate from a desired shape, resulting in a defective product.

  FIG. 5 illustrates a phenomenon in which the load acting on the cutter 10 becomes unbalanced when the cutting edge portion 10 </ b> A of the cutter 10 comes out from the workpiece 1, using a development view of the workpiece 1. In the figure, the actual cutting region that functions to form the tooth gap 1S in the cutting edge portion 10A of the cutter 10 is a leading side region 10L and a trailing side region 10T, and each is hatched differently. ing. Further, the cutting edge portion 10A at the left end of the figure shows the situation before the workpiece 1 is pulled out, and the cutting blade portion 10A on the right side sequentially shows the situation where the cutting blade portion 10A is pulled out from the workpiece 1.

  That is, in skiving, the leading side region 10L and the trailing side region 10T of the cutting edge portion 10A of the cutter 10 are involved in cutting, but the leading side region 10L precedes the trailing side region 10T.

  As shown at the left end of the figure, at the time of cutting (when cutting is continued), the leading side region 10L of the cutting edge portion 10A and the trailing side region 10T come into contact with the tooth groove 1S of the workpiece 1 on a wide surface. The load acting on the leading side region 10L and the load acting on the trailing side region 10T are in a balanced state and do not cause vibration. The incomplete tooth groove 1Su formed in the workpiece 1 when the cutter 10 is separated from the workpiece 1 in the first cutting step (# 02) and the second cutting step (# 05) described later is shown in FIG. The leading side region 10L shown at the left end of FIG. 5 and the trailing side region 10T are combined.

  On the other hand, when the cutting progresses and a part of the cutting edge portion 10A reaches a state where the cutting edge portion 10A comes out of the workpiece 1, the contact area between the cutting edge portion 10A and the workpiece 1 decreases and the state shifts to an unstable state. Since the area in contact with the workpiece 1 in the trailing side region 10T changes to be larger than the area in contact with the workpiece 1 in the leading side region 10L, the load acting on the cutter 10 becomes unbalanced and causes vibration. .

  Thereby, due to the vibration when the cutting edge portion 10A of the cutter 10 comes out of the workpiece 1, the width of the tooth gap 1S changes as indicated by a virtual line at the right end of the figure, and as a result, the tooth profile is a desired shape. Greatly changes. Although not shown in the drawing, the load acting on the cutting edge portion 10A becomes unbalanced due to the same phenomenon at the start of cutting, causing vibrations and changing the width of the tooth groove 1S (an error occurs).

[Gear processing]
In the gear machining method of the present invention, it is possible to continuously produce a good gear by suppressing the vibration of the cutter 10 described above during cutting by the cutter 10.

  That is, a plurality of workpieces 1 are overlapped and held by the clamp unit C, and a plurality of workpieces 1 are cut at a time to realize processing of a gear having a good tooth surface. This is shown in the gear machining procedure of FIG.

  In this processing procedure, the first clamping step (# 01) and the first cutting step (# 02) are performed in this order, and whether or not the new workpiece 1 used for the next clamping is the final lot. Is determined (# 03). If it is not the final lot according to this determination, the second clamping step (# 04) and the second cutting step (# 05) are performed in this order, and a new workpiece 1 used for the next clamping is again obtained. It is determined whether or not it is the final lot (# 03).

  If the new workpiece 1 is not the final lot as determined by # 03, the second clamping step (# 04) and the second cutting step (# 05) described above are repeated. On the other hand, when the new workpiece 1 is the final lot, the third clamping step (# 06) and the third cutting step (# 07) are performed in this order, and the processing is completed. The form of tooth gap 1S etc. which are formed in work 1 in these processes is explained below.

  In the first clamping step (# 01), a plurality of workpieces 1 are fitted in a state where they are superimposed on the clamp body 15, and are held in an integrated state by artificially tightening the clamp nut 16.

  Thus, the clamp unit C in which a plurality of workpieces 1 are integrated is held on the table 2 by the chuck 3 and the first operation of the first cutting step (# 02) is performed. In this first operation, as shown in FIG. 7A, cutting is performed by moving the cutter 10 in a direction parallel to the workpiece axis T. Next, following the first operation, as shown in FIG. 7 (b), the cutter 10 is moved before the cutting position passes through the one at the most downstream position in the cutting direction (the lowermost workpiece) among the plurality of workpieces 1. Is moved away from the workpiece (this is the second operation).

  In this first cutting step (# 02), the table 2 and the cutter 10 are synchronously driven and rotated by the synchronous rotation controller 21, and the position of the cutter 10 relative to the table 2 is determined by the control of the first operation module 22A. Control is performed to set the depth and shift the table 2 in the direction along the workpiece axis T. Thus, the tooth groove 1S having a desired depth is formed in a straight line parallel to the workpiece axis T, and a tooth portion is formed.

  Following this, by the control of the second operation module 22B, the workpiece by the first operation module 22A before the cutting position passes the one at the most downstream position in the cutting direction (the lowermost workpiece) among the plurality of workpieces 1. A second operation is performed in which the movement in the direction along the axis T is stopped and the cutter 10 is moved away from the inner periphery of the workpiece 1 by moving in the direction orthogonal to the workpiece axis T.

  Due to this separation, an incomplete tooth groove 1Su remains on the workpiece 1 as shown in FIG. 7B, and the workpiece 1 at the most downstream position in the cutting direction (lowermost workpiece) among the plurality of workpieces 1 has imperfect teeth. An incomplete workpiece 1u in which the groove 1Su is formed is formed. As a result, a state in which the load acting on the cutting edge portion 10A of the cutter 10 is balanced at the time of cutting is maintained, so that the tooth gap 1S is formed with a desired width without vibrating the cutter 10.

  In the first cutting step (# 02), the upstream end in the cutting direction causes a phenomenon that the cutter 10 vibrates during cutting, and the leading tooth groove 1Sp that causes an error from the desired tooth groove 1S is generated. There may be a defective product formed. Therefore, in this cutting, a finished product having a good tooth surface is obtained by removing the end portion on the upstream side in the cutting direction and the portion in which the incomplete tooth groove 1Su is formed on the downstream side in the cutting direction. .

  After the first cutting step (# 02), it is determined whether or not the new workpiece 1 used for the next clamping is the final lot (# 03). If it is not the final lot by this determination, in the second clamping step (# 04), the unfinished workpiece 1u in which the incomplete tooth groove 1Su is formed as shown in FIG. The posture is set so that the incomplete tooth groove 1Su is opened upstream (the posture in which the opening is opened), and the workpiece is integrated and held on a plurality of new workpieces 1 by tightening the clamp nut 16.

  In particular, when the workpiece 1 is thin, a plurality of unfinished workpieces 1u are created in the first cutting step (# 01). When a plurality of unfinished workpieces 1u are created in this way, in the second clamping step (# 04), the posture restricting portion 15D of the clamp body 15 is fitted into the recess 1A of the unfinished workpiece 1u. Is set at a position where the incomplete tooth spaces 1Su overlap.

  If the new workpiece 1 to be clamped is not the final lot based on the determination of # 03, the second clamping step (# 04) and the second cutting step (# 05) are repeated. In the second cutting step (# 05), the position of the tooth gap 1S of the unfinished workpiece 1u is detected by the tooth gap sensor 18 so that the phase setting section 23 matches the cutting position by the cutting edge part 10A of the cutter 10. Phase setting is performed. Thereafter, as shown in FIG. 7 (d), the first operation module 22A performs the first operation in the direction of extending the incomplete tooth gap 1Su, and subsequently, the second operation module 22B performs separation. Is called. That is, similarly to the first cutting step (# 02), the first operation is stopped immediately before the cutter 10 reaches the lowermost workpiece (the movement in the direction along the workpiece axis T is stopped). By moving in a direction orthogonal to the axis T, a second operation for separating the cutter 10 from the inner periphery of the workpiece 1 is performed.

  As a result, the unfinished workpiece 1u used in the second clamping step (# 04) and the newly used workpiece 1 have a good tooth groove 1S required by linear cutting by the first operation. You will get a gear that is formed and completed.

  If the new workpiece 1 to be clamped in the determination of # 03 is the final lot, the third clamping step (# 06) and the third cutting step (# 07) are performed.

  In the third clamping step (# 06), similarly to the second clamping step (# 04) described above, as shown in FIG. 7E, the unfinished workpiece 1u and the new workpiece 1 are overlapped to form a clamping unit. C is integrated and held.

  In the third cutting step (# 07), the position of the tooth gap 1S of the unfinished workpiece 1u is detected by the tooth gap sensor 18 with the clamp unit C held on the table 2, and the phase setting unit 23 Phase setting is performed so as to coincide with the cutting position by the cutting edge portion 10A. Thereafter, as shown in FIG. 7 (f), the first operation is continuously performed by the first operation module 22A, so that the cutting position passes through the plurality of workpieces 1 at the most downstream position in the cutting direction. Let

  As a result, the unfinished workpiece 1u used in the third clamping step (# 06) and the newly used workpiece 1 have a good tooth groove 1S required by linear cutting by the first operation. You will get a gear that is formed and completed.

  As described above, when the plurality of workpieces 1 are cut by the cutter 10 in the first cutting step (# 02) after the first clamping step (# 01), the plurality of workpieces 1 processed by the first operation are formed. The required good tooth surface is created, and no burr is formed on the workpiece 1.

  Further, among the plurality of workpieces 1, the workpiece 1 includes an incomplete workpiece 1 u in which an incomplete tooth groove 1 Su is formed due to separation (by the second operation). The unfinished workpiece 1u is superimposed on a plurality of new workpieces 1 by the second clamping step (# 04) or the third clamping step (# 06), and the second cutting step (# 05) or the third cutting step (# 07). ), The burrs are not formed on the other workpieces 1 except for the workpiece 1 at the most downstream position (the lowermost workpiece), and the necessary good tooth surface is formed.

  In particular, in this processing method, since a plurality of workpieces 1 are overlapped and cut with a cutter, a plurality of gears can be manufactured all at once, and the processing efficiency can be increased.

[Modification of gear machining]
When the new workpiece 1 used in the clamping process is the final lot, as shown in FIG. 8A, an incomplete workpiece 1u in which an incomplete tooth groove 1Su is formed, and a plurality of new workpieces 1 are formed. And the first work 1p (see FIGS. 7A and 7B) in which the first tooth groove 1Sp is formed by cutting at the first position in the first cutting step (# 02), and the clamp unit Crimp and hold with C.

  In the case of holding in this way, the workpiece 1 in which the incomplete tooth groove 1Su is formed is set in a posture in which the tooth groove 1S is opened on the upstream side in the cutting direction, as described above. Note that the direction of the leading tooth gap 1Sp of the leading workpiece 1p need not be considered.

  Next, in a state where the clamp unit C is held on the table 2, the position of the incomplete tooth groove 1Su of the unfinished workpiece 1u is detected by the tooth gap sensor 18, and the phase setting unit 23 performs cutting by the cutting edge part 10A of the cutter 10. Set the phase to match the position.

  Thereafter, as shown in FIG. 8 (b) as in the second cutting step (# 05), the first operation is continuously performed by the first operation module 22A, so that the cutting position is among the plurality of workpieces 1. The one in the most downstream position in the cutting direction is passed.

  In skiving, the leading workpiece 1p that is first cut in the first cutting step (# 02) may become a defective tooth surface in which an error occurs in the leading tooth groove 1Sp due to vibration of the cutter 10.

  Therefore, by disposing the workpiece 1 as in this modification and performing the cutting in the third cutting step (# 06), the workpiece 1 is disposed at the end position on the downstream side in the cutting direction in the cutting step. Even if there is an inconvenience that an error may occur in the tooth groove shape of the work 1 at the most downstream position (the lowermost work) in the cutting direction of the 3 cutting process (# 07), the work 1 at the most downstream position is Since there is a high possibility of becoming a defective product, the number of defective products is not increased.

[Effect of the embodiment]
In this gear machining method, the necessary good tooth surfaces are created on the plurality of workpieces 1 machined by the first operation, and burrs are not formed on the workpiece 1. Further, the unfinished workpiece 1u created by cutting is superposed on a plurality of new workpieces by the second clamping step (# 04), and the unfinished workpiece 1u is not wasted by the second cutting step (# 05). It becomes possible to manufacture a gear having a good tooth surface.

  Moreover, in this processing method, since a plurality of workpieces 1 are cut in a superimposed state, a plurality of gears can be manufactured all at once, and the processing efficiency can be increased. In particular, even when a thin workpiece 1 is machined, the machining accuracy can be improved without causing the workpiece 1 to vibrate to lower the cutting accuracy or causing the workpiece 1 to be deformed.

  In the first cutting step (# 02), a plurality of unfinished workpieces 1u may be created depending on the thickness of the workpiece 1, but even when a plurality of unfinished workpieces 1u are created, the second clamping step (## 04), since the workpiece 1 is overlapped in such a manner that the posture regulating portion 15D on the inner periphery of the clamp body 15 is fitted into the recess 1A of the workpiece 1, the position of the tooth groove 1S is matched even if there are a plurality of unfinished workpieces 1u. Can be processed.

  Also, as shown in [Modification of Gear Machining], it is possible to reduce the waste of the workpiece 1 by arranging the workpiece 1 and performing cutting.

[Another embodiment]
The present invention may be configured as follows in addition to the embodiment described above.

(A) As shown in FIGS. 9 and 10, a protrusion 1 b is formed on one surface of the workpiece 1 as a positioning portion, and a fitting recess 1 d is formed on the back side. As a result, when clamping a plurality of unfinished workpieces 1u in the second clamping step (# 04), the phases of the incomplete tooth grooves 1Su are matched by fitting the protrusions 1b into the fitting recesses 1d. It becomes easy.

  In addition, as a positioning part, you may employ | adopt the structure which uses the engagement piece fitted in incomplete tooth space 1Su.

(B) As shown in FIG. 11A, as the first cutting step (# 02), the cutter 10 is moved closer to the inner peripheral surface of the workpiece 1 from the direction inclined with respect to the workpiece axis T to start cutting. Then, the process proceeds to linear cutting by the first operation, and further, the first operation of the cutter 10 is performed before passing through the work 1 at the most downstream position in the cutting direction as shown in FIG. The cutting mode is set so as to perform the second operation for stopping the movement by the above and separating the cutting edge portion 10A of the cutter 10 from the workpiece.

Also in the processing method of this alternative embodiment (b), in the first cutting step (# 02), the leading incomplete work 1t in which the leading incomplete tooth groove 1St is formed by the initial cutting is formed and incomplete due to the separation. An incomplete workpiece 1u having a tooth gap 1Su is formed. Furthermore, this first cutting step (
In # 02), the same cutting as in the embodiment is performed in that the second operation is performed after the first operation.

  Even in the case of performing the first cutting step (# 02) in this way, the determination (# 03) shown in the embodiment is performed, and in the second clamping step (# 04), the unfinished workpiece 1u and the workpiece 1 are clamped. (Clamp similar to the embodiment) is performed, and the second cutting step (# 05) is performed as in the embodiment.

  In the third clamping step (# 06), as shown in FIG. 11 (c), the unfinished workpiece 1u in which the incomplete tooth groove 1Su is formed, a plurality of new workpieces 1, and the first cutting step ( In (# 02), the head incomplete tooth 1St in which the head incomplete tooth groove 1St is formed is superposed and pressed and held by the clamp unit C. After this, by performing the first operation in the third cutting step (# 07), machining without creating any defective gear is realized.

(C) The skiving machine increases the rotation angle of the cutter 10 centered on the cutter axis S and the sensor such as a rotary encoder that detects the rotation angle of the table 2 centered on the workpiece axis T with high accuracy. An apparatus including a sensor such as an encoder that detects with high accuracy includes a fitting structure for determining a relative posture between the table 2 and the clamp body 15 with respect to the workpiece axis T. As a result, the phase of the incomplete tooth groove 1Su in the workpiece 1 supported by the table 2 can be grasped from the rotational phase of the table 2, and the tooth gap sensor 18 can be omitted.

(D) The first clamping step (# 01) and the second clamping step (# 04) described above are assumed to be realized by human work, but at least one of these is realized by automation. Alternatively, a skiving apparatus may be configured.

(E) As a skiving machine, the table 2 is rotated in a fixed position and the cutter 10 is moved relative to the workpiece 1 in the direction of the workpiece axis T of the workpiece 1. You may employ | adopt the structure supported by a joint robot arm etc.

(F) A hobbing machine may be configured as an apparatus for realizing the gear machining method of the present invention. When the hobbing machine is configured in this way, the cutting form of the workpiece 1 by the cutter 10 is different, but a plurality of workpieces 1 are overlapped and held, so that a good surface that does not generate burrs appears. .

  INDUSTRIAL APPLICABILITY The present invention can be used in a gear machining method for machining gears by synchronously driving and rotating a workpiece and a cutter.

1 Workpiece 1A Positioning part (recess)
1Su Incomplete tooth groove 1u Incomplete workpiece 10 Cutter S Cutter shaft core T Work shaft core # 01 First clamping step # 02 First cutting step # 04 Second clamping step # 05 Second cutting step

Claims (5)

A first clamping step in which a plurality of workpieces are stacked and held along the workpiece axis;
The workpiece is moved upstream by the cutter by a first operation in which the cutter moves along the workpiece axis while the plurality of workpieces held in the first clamping step and the pinion-shaped cutter rotate synchronously. At least by the second operation in which the cutter is separated from the lowermost workpiece before passing through the lowermost workpiece arranged at the most downstream position in the cutting direction among the plurality of workpieces. A first cutting step in which an incomplete tooth gap is formed in the lowermost workpiece;
After the first cutting step, a determination step for determining whether or not the new workpiece used in the next cutting step is a final lot is performed,
If it is determined in the determination step that the new workpiece is not the final lot,
And unfinished workpiece in a state where the opening of the incomplete tooth grooves formed in the first cutting step is opened to the upstream side of the cutting direction, the unfinished workpiece positioned under flow side of the cutting direction than A second clamping step of holding the at least one new workpiece to be overlapped and held along the workpiece axis ;
The first operation is performed such that the incomplete tooth gap of the unfinished workpiece is cut in a state in which the plurality of workpieces and the pinion-shaped cutter that are overlapped in the second clamping step are synchronously driven and rotated. Subsequently, a second cutting step of obtaining a new incomplete workpiece in which another incomplete tooth gap is formed in at least the lowermost workpiece among the new workpieces by performing the second operation ,
Is done,
If it is determined in the determination step that the new workpiece is the final lot,
An incomplete work in a state in which the opening of the incomplete tooth gap formed in the first cutting step is opened to the upstream side in the cutting direction, and disposed downstream of the incomplete work in the cutting direction. A third clamping step of holding the at least one new workpiece overlapped along the workpiece axis;
The first operation is performed such that the incomplete tooth gap of the unfinished workpiece is cut in a state in which the plurality of workpieces and the pinion-shaped cutter that are overlapped in the third clamping step are synchronously driven and rotated. A third cutting step in which the workpiece is cut by continuously performing the first operation until it passes through all new workpieces;
Gear processing method in which is performed . The leading work in which a leading tooth groove is formed by cutting at the leading position in the first cutting step is disposed downstream in the cutting direction from the new workpiece in the third clamping step. The gear machining method according to 1. In the first cutting step, cutting is started by bringing the cutter closer to the workpiece from a direction inclined with respect to the workpiece axis, and then the first operation is performed on the upstream side of the cutting direction. A leading unfinished workpiece with a leading incomplete tooth gap is formed,
2. The gear machining method according to claim 1, wherein in the third clamping step, the leading unfinished workpiece is disposed downstream of the new workpiece in the cutting direction . The plurality of workpieces include a positioning unit that determines a posture around the workpiece axis, and the positions of the plurality of workpieces are determined by the positioning unit in the second clamping step . The gear machining method according to one item . Said first cutting step, the second cutting step, and, in the third cutting step, the cutter is arranged to the cutter axis is different from the work axis of the plurality of the workpiece, the plurality of the work The method according to any one of claims 1 to 4, wherein a plurality of workpieces and the cutter are moved relative to each other along a tooth trace direction of a tooth profile formed on the workpiece while the cutters are driven synchronously. The gear machining method according to Item .

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