JP6797648B2 - Gear processing method and gear fixing device - Google Patents

Description

The present invention relates to a gear processing method for suppressing the generation of burrs on the end face of a gear to be machined when gear cutting, and a gear fixing device used in the gear processing method.

As one method of machining a gear, a gear machining method in which the gear to be machined is geared by giving a cut and a feed to the cutting tool while rotating the gear to be machined and the cutting tool synchronously. However, it has been provided conventionally. In such a gear processing method, for example, the cutting tool is geared in the feed process which is the outward path, and is retracted from the gear to be machined in the return process which is the return path. For this reason, burrs are generated on the end face on the downstream side in the feed direction of the gear to be processed.

Further, when a gear having burrs as described above is assembled to other parts, the assembly accuracy is lowered, and the burrs that fall off after assembly invade the sliding part and the rotating part and hinder their operation. There is a risk of As a result, when burrs are generated after gear cutting, some kind of deburring work is required, which requires a large amount of man-hours.

Therefore, in the technical field of gear processing in recent years, various gear processing methods are provided in which burrs are taken at the same time as processing. As such a conventional gear processing method, for example, Patent Documents 1 and 2 are disclosed.

Japanese Unexamined Patent Publication No. 2008-30162 Japanese Unexamined Patent Publication No. 2016-32850

In Patent Document 1, a waste washer is brought into surface contact with the end surface on the downstream side in the feed direction of the external gear to be machined, and both the external gear to be machined and the waste washer are geared to be downstream in the feed direction of the external gear to be machined. The generation of burrs on the side end faces is suppressed. However, in such a conventional gear processing method, one waste washer is required for each gear cutting of one external gear to be processed, which leads to an increase in manufacturing cost.

Further, in Patent Document 2, when a plurality of internal gears to be machined that are overlapped and integrated are cut at once by a pinion cutter, the work piece is arranged at the most downstream position in the feed direction at the time of the previous gear cutting. By arranging the internal gear to be machined at the most upstream position in the feed direction, burrs generated on the end face on the downstream side in the feed direction of the internal gear to be machined are removed.

However, in such a conventional gear machining method, it is necessary to superimpose the burr-generated internal gear to be machined on another internal gear to be machined at the next gear cutting. As a result, in order to prevent the burr from coming into contact with the other internal gear to be machined, it is necessary to change the burr generation direction to a predetermined direction.

Specifically, the pinion cutter is temporarily stopped in the middle of feeding, and then the feeding operation is performed again while moving the pinion cutter inward in the radial direction from the internal gear to be machined. As a result, burrs generated in the internal gear to be machined are projected inward in the radial direction from the inner peripheral surface. That is, in the above-mentioned conventional gear processing method, the gear cutting operation of the pinion cutter is complicated in order to define the direction in which burrs are generated.

Further, in the above-mentioned conventional gear machining method, the rotation phase alignment between the pinion cutter and the internal gear to be machined arranged at the most upstream position in the feed direction must be performed prior to gear cutting. Furthermore, in order to prevent misalignment in the circumferential direction when a plurality of internal gears to be machined are overlapped, it is not only necessary to pre-process the misalignment preventing means for the internal gear to be machined. Along with this, an unnecessary shape is left in the internal gear which is a finished product.

Therefore, the present invention solves the above problems, and is a gear processing method and a gear that can easily suppress the generation of burrs on the end face on the downstream side in the feed direction of the workpiece while suppressing an increase in manufacturing cost. An object is to provide a fixing device.

The gear processing method according to the first invention for solving the above problems is
In a gear machining method in which a work piece is geared by the tool by giving an axial feed of the work piece to the tool while rotating the work piece and the tool.
The end face on the downstream side in the feed direction of the work piece of the first product is brought into surface contact with the lower jig.
The work piece of the first product and the lower jig are coaxially overlapped with each other.
The work piece of the first product is pressed and fixed toward the fixed lower jig.
Both the work piece of the first product and the fixed lower jig are gear-cut with the tool.
The fixed state of the lower jig when the teeth are cut together with the work piece of the first product is maintained as it is.
The end face on the downstream side in the feed direction of the work piece after the next product is brought into surface contact with the lower jig in which the fixed state is maintained.
The work piece after the next product and the lower jig maintained in the fixed state are coaxially overlapped.
The work piece after the next product is pressed and fixed toward the lower jig in which the fixed state is maintained.
A gear cutting operation when the work piece of the first product is geared with respect to the tool while maintaining an meshable rotational phase relationship between the tool and the lower jig in which the fixed state is maintained. By giving the same gear cutting operation as above, only the workpiece after the next product is geared.

The gear processing method according to the second invention for solving the above problems is
If the tool is replaced when cutting the workpiece after the next product,
Prior to gear cutting with the replaced tool
The rotation phase of the exchanged tool is changed so that the exchanged tool and the lower jig in which the fixed state is maintained have a rotational phase relationship that allows meshing with the lower jig. It is characterized by matching with the rotation phase of the tool.

The gear processing method according to the third invention for solving the above problems is
The work piece of the first product or the work work of the next product or later is coaxially formed from both sides in the axial direction by the upper jig and the lower jig arranged on the upstream side in the feed direction from the lower jig. The tool is characterized in that it cuts the work piece of the first product or the work piece of the next product or later without cutting the upper jig.

The gear fixing device according to the fourth invention that solves the above problems is
When the work piece is geared by the tool by giving the work piece an axial feed to the work piece while rotating the work piece and the tool, the work piece is said to be the work piece. In the gear fixing device that fixes
A rotary table rotatably supported around the axis of the workpiece and
While being fixed to the rotary table, the peripheral surface that comes into surface contact with the end surface on the downstream side in the feed direction of the workpiece and is geared with the tool together with the peripheral surface of the workpiece, or the workpiece is toothed. A lower jig having a tooth profile that meshes with the tool immediately after cutting,
And characterized in that it comprises, an upper jig for fixing sandwich from both axial sides coaxially between said lower jig are arranged in a direction upstream of the feed than the workpiece, the lower jig To do.

The gear fixing device according to the fifth invention that solves the above problems is
It is characterized by including a fitting portion formed on the lower jig and fitted with the work piece to position the work piece in the radial direction.

The gear fixing device according to the sixth invention for solving the above problems is
A protrusion that projects from the end surface on the downstream side in the feed direction of the upper jig toward the downstream side in the feed direction and presses the end surface on the upstream side in the feed direction of the workpiece.
A connecting bolt that connects the upper jig and the lower jig in the axial direction,
It is provided with a bolt hole that penetrates the upper jig in the axial direction and into which the connecting bolt is inserted.
The bolt hole is opened adjacent to the protrusion.

Therefore, according to the gear processing method and the gear fixing device according to the present invention, when cutting a plurality of workpieces, it is possible to continue to use the pair of upper and lower upper jigs and lower jigs without exchanging them. .. Further, even if the upper jig and the lower jig are installed, they do not affect the gear cutting operation of the tool. Therefore, it is possible to easily suppress the occurrence of burrs on the end face on the downstream side in the feed direction of the workpiece while suppressing an increase in manufacturing cost.

It is a figure which shows the outline of the gear processing method and the gear fixing device which concerns on one Example of this invention. It is a vertical sectional view of the gear fixing device which concerns on one Embodiment of this invention. It is a perspective view which looked at the upper jig from the downstream side in the feed direction. It is a figure which showed the state before processing the 1st work. It is an operation diagram following FIG. 4A, and is a diagram showing a state after processing the first work. It is a figure which showed the state before processing the second and subsequent workpieces. It is an operation diagram following FIG. 4C, and is a diagram showing a state after processing the second and subsequent workpieces. It is a figure which showed the rotation phase matching operation between a pinion cutter and a lower jig at the time of cutter exchange.

Hereinafter, the gear processing method and the gear fixing device according to the present invention will be described in detail with reference to the drawings. In the embodiments described below, the gear processing method and the gear fixing device according to the present invention are the gear processing method for cutting internal gears by using skiving processing, and the gear fixing device used in the method. The case where it is applied to is specifically explained.

As shown in FIGS. 1 and 2, a rotary table 11 is rotatably supported around a work rotation axis C, which is a vertical axis, on an upper portion of a gear cutting machine (not shown). The upper part of the rotary table 11 has a cylindrical shape, and a ring-shaped work (workpiece, gear material) W forms a ring-shaped upper and lower pair on the mounting surface 11a which is the upper surface of the cylindrical upper part. It is detachably fixed by the upper jig 21 and the lower jig 22.

That is, the upper jig 21 is arranged above the work W, while the lower jig 22 is arranged below the work W. Then, by fixing the work W to the mounting surface 11a of the rotary table 11 via the upper jig 21 and the lower jig 22, the work W, the upper jig 21, and the lower jig 22 are coaxial. The central axes of these are aligned with the work rotation axis C, which is the rotation center of the rotary table 11.

Therefore, after fixing the work W to the mounting surface 11a of the rotary table 11 via the upper jig 21 and the lower jig 22, the rotary table 11 is rotated around the work rotation axis C, so that the work W, upper With the jig 21 and the lower jig 22 integrated, the work rotation axis C can be used as the center of rotation for rotation.

Further, the spindle 12 is movablely supported on the gear cutting machine and tiltably supported with respect to the work rotation axis C, and the spindle 12 is rotatable around the cutter rotation axis B. .. Further, a pinion cutter (gear-shaped tool) 13 whose external teeth are helical gears is detachably attached to the tip of the spindle 12 as a cutting tool for gear cutting. Then, by mounting the pinion cutter 13 on the tip of the spindle 12, the central axis of the pinion cutter 13 coincides with the cutter rotation axis B which is the rotation center of the spindle 12.

Therefore, by mounting the pinion cutter 13 on the spindle 12 and then rotating the spindle 12 around the cutter rotation axis B, the pinion cutter 13 can be rotated with the cutter rotation axis B as the center of rotation. Further, by moving the spindle 12 in the radial direction of the work W and the axial direction of the work W, it is possible to give the pinion cutter 13 a radial cut and a feed in the axial direction (work rotation axis direction). it can.

Then, when a feed is given to the pinion cutter 13, the pinion cutter 13 reciprocates along the axial direction of the work W. At this time, in the pinion cutter 13, the work W and the lower jig 22 are both tooth-cut when moving downward, while the diameter from the work W and the lower jig 22 is increased when moving upward. The work W and the lower jig 22 are separated from each other toward the inside in the direction so as not to be tooth-cut.

Specifically, the pinion cutter 13 cuts the inner peripheral surface Wa from the upper end surface Wb which is the upstream end surface of the work W in the feed direction to the lower end surface Wc which is the downstream end surface of the work W in the feed direction. In succession to this, the inner peripheral surface 22a is geared by cutting into the fitting portion 22d which is the end surface on the upstream side in the feeding direction of the lower jig 22. Therefore, the tooth profile cut by the pinion cutter 13 is formed on the entire axial direction of the inner peripheral surface Wa and the inner peripheral surface 22a, and the work W and the lower jig 22 are, for example, internal tooth spur gears. Is processed into.

That is, the upper jig 21 and the lower jig 22 form a gear fixing device for fixing the work W to the mounting surface 11a of the rotary table 11. The details will be described later, but among them, the lower jig 22 is the first (first product) work W for the purpose of suppressing the occurrence of burrs on the lower end surface Wc of the work W at the time of gear cutting. At the time of gear cutting, the pinion cutter 13 cuts the teeth together with the work W, and at the time of gear cutting of the second and subsequent work W (after the next product), the pinion is not cut by the pinion cutter 13. It can mesh with the cutter 13.

Note that FIG. 2 is a vertical cross-sectional view of the gear fixing device shown in FIG. 1, but in order to make it easier to understand the gear cutting to the work W and the lower jig 22, the work W and the lower jig 22 shown in FIG. The tool 22 is in the state after gear cutting, while the work W and the lower jig 22 shown in FIG. 2 are in the state before gear cutting.

Next, the configuration of the gear fixing device will be described in detail with reference to FIGS. 1 to 3.

As shown in FIGS. 1 and 2, the upper jig 21 has an inner diameter larger than the inner diameter of the work W and an outer diameter larger than the outer diameter of the work W, and has an inner peripheral surface. It has a 21a, an upper end surface 21b, a lower end surface 21c, a protruding portion 21d, and a bolt hole 21e.

The inner peripheral surface 21a is arranged radially outside the inner peripheral surface Wa of the work W. An annular upper end surface 21b, which is an end surface on the upstream side of the upper jig 21 in the feeding direction, is formed on the upstream side of the inner peripheral surface 21a in the feeding direction. On the other hand, on the downstream side of the inner peripheral surface 21a in the feeding direction, an annular lower end surface 21c, which is an end surface on the downstream side in the feeding direction of the upper jig 21, is formed. The lower end surface 21c of the upper end surface Wb of the work W faces only the outer peripheral portion thereof in the axial direction. As a result, even if the pinion cutter 13 cuts the work W and the lower jig 22, the upper jig 21 is not cut by the pinion cutter 13.

Further, as shown in FIGS. 2 and 3, a plurality of protruding portions 21d are formed on the lower end surface 21c. These projecting portions 21d project from the lower end surface 21c toward the downstream side in the feeding direction, and are formed radially around the work rotation axis C. That is, the protruding portions 21d extend in the radial direction and are arranged at equal intervals in the circumferential direction. As a result, among the parts constituting the upper jig 21, only the protruding portion 21d comes into line contact with the upper end surface Wb of the work W, and the protruding portion 21d feeds the upper end surface Wb of the work W upstream. It can be pressed from the side to the downstream side.

Further, the upper jig 21 is formed with a plurality of bolt holes 21e penetrating in the axial direction. These bolt holes 21e are arranged on the outer side of the protrusion 21d in the radial direction and at equal intervals in the circumferential direction, and the number of bolt holes 21e is the same as the number of the protrusions 21d. That is, the bolt hole 21e is arranged at the same position in the circumferential direction as the protrusion 21d, and is opened so as to be adjacent to the radial outer end of the protrusion 21d. Then, a connecting bolt 23, which will be described later, can be inserted into the bolt hole 21e.

On the other hand, as shown in FIGS. 1 and 2, the inner diameter of the lower jig 22 is the same as the inner diameter of the work W, and the outer diameter is larger than the outer diameter of the work W. , Inner peripheral surface 22a, upper end surface 22b, lower end surface 22c, and fitting portion 22d.

The inner peripheral surface 22a is arranged at the same position in the radial direction as the inner peripheral surface Wa of the work W. An annular upper end surface 22b, which is an end surface on the upstream side of the lower jig 22 in the feeding direction, is formed on the upstream side of the inner peripheral surface 22a in the feeding direction. On the other hand, on the downstream side of the inner peripheral surface 22a in the feeding direction, an annular lower end surface 22c, which is an end surface on the downstream side in the feeding direction of the lower jig 22, is formed.

Further, an annular fitting portion 22d is formed inside the lower jig 22 in the radial direction and on the upstream side in the feed direction of the lower jig 22. The end portion on the downstream side in the feed direction of the work W can be fitted into the fitting portion 22d.

That is, the fitting portion 22d is open over the inner peripheral surface 22a and the upper end surface 22b, and is in surface contact with the lower end surface Wc and the outer peripheral surface Wd of the work W. In this way, the work W fitted to the fitting portion 22d is formed in a radial direction by forming the fitting portion 22d into a notch shape such that the fitting portion 22d is cut out over the inner peripheral surface 22a and the upper end surface 22b. The deviation will be regulated. That is, the fitting portion 22d can position the work W in the radial direction.

Further, by fitting the work W to the fitting portion 22d of the lower jig 22, the inner peripheral surface Wa of the work W and the inner peripheral surface 22a of the lower jig 22 can be matched in the radial direction. Therefore, since both the work W and the lower jig 22 can be gear-cut, the tooth profile formed on the work W and the tooth profile formed on the lower jig 22 match.

From the above, when the work W and the lower jig 22 are continuously geared, the blade portion of the pinion cutter 13 that has come out from the lower end surface Wc of the work W must be cut into the fitting portion 22d of the lower jig 22. become. Therefore, since the lower end surface Wc of the work W and the fitting portion 22d of the lower jig 22 are in close contact with each other without a gap, burrs are formed on the lower end surface Wc of the work W on the downstream side in the feed direction from the lower end surface Wc. It becomes difficult to occur toward.

That is, in order to suppress the occurrence of burrs on the lower end surface Wc of the work W, the blade portion of the pinion cutter 13 protruding from the lower end surface Wc may be cut into the fitting portion 22d of the lower jig 22. Therefore, in the present embodiment, the inner diameter of the work W and the inner diameter of the lower jig 22 are the same inner diameter, but the inner diameter of the lower jig 22 may be an inner diameter equal to or less than the inner diameter of the work W.

On the other hand, the lower end surface 22c is in surface contact with the entire mounting surface 11a. The mounting surface 11a has the same inner diameter and outer diameter as the inner diameter and outer diameter of the upper jig 21. As a result, even if the pinion cutter 13 cuts the work W and the lower jig 22, the rotary table 11 is not cut by the pinion cutter 13.

Further, the upper jig 21 and the lower jig 22 are connected by a plurality of connecting bolts 23. These connecting bolts 23 are arranged radially outside the outer peripheral surface Wd of the work W and at equal intervals in the circumferential direction, and penetrate the bolt holes 21e of the upper jig 21 in the axial direction. It is screwed into the lower jig 22 from the axial direction. The connecting bolt 23 may be screwed into the rotary table 11 via the lower jig 22.

In this way, the upper jig 21 is pulled toward the lower jig 22 by penetrating the plurality of connecting bolts 23 through the bolt holes 21e of the upper jig 21 and fastening them in the lower jig 22. .. As a result, the work W can be sandwiched and fixed between the protruding portion 21d and the fitting portion 22d.

At this time, the fastening force of the connecting bolt 23 acts as a pressing force in which the protruding portion 21d presses the work W toward the fitting portion 22d. Further, since the connecting bolt 23 is penetrated into the bolt hole 21e adjacent to the protruding portion 21d, the head of the connecting bolt 23 is engaged at a position facing the protruding portion 21d on the upper end surface Wb in the axial direction. Stop. As a result, the fastening force of the connecting bolt 23 can be efficiently converted into the pressing force of the protruding portion 21d, so that the work W can be pressed by a large pressing force. As a result, the work W can be firmly fixed.

This point will be described by comparing the upper jig 21 having a plurality of protruding portions 21d with the conventional upper jig 21 having no protruding portions 21d. However, it is assumed that the shape and area of the lower end surface 21c are the same as the shape and area of the lower end surface of the conventional upper jig.

Here, when connecting the upper jig 21 and the conventional upper jig using a plurality of connecting bolts 23, the quantity and the penetration position of the connecting bolts 23 used for each are set to the same quantity and the same position. To do. That is, a fastening force of the same magnitude is applied to the upper jig 21 and the conventional upper jig. As a result, the upper jig 21 is pressed only by the plurality of protrusions 21d, whereas the conventional upper jig is pressed over the entire lower end surface, so that the pressing force by the plurality of protrusions 21d is applied. , It becomes larger than the pressing force by the entire lower end surface. That is, in the upper jig 21, the pressing force per unit area is increased by pressing by the plurality of protruding portions 21d rather than by pressing by the entire area of the lower end surface 21c.

Further, the lower jig 22 is fixed to the mounting surface 11a of the rotary table 11 by a plurality of fixing bolts 24. These fixing bolts 24 are arranged radially outside the outer peripheral surface Wd of the work W and at equal intervals in the circumferential direction, penetrate the lower jig 22 in the axial direction, and are inside the rotary table 11. Is screwed in from the axial direction. The connecting bolts 23 and the fixing bolts 24 are alternately arranged in the circumferential direction.

In this way, the lower jig 22 can be fixed to the mounting surface 11a by passing the plurality of fixing bolts 24 through the lower jig 22 and fastening them in the rotary table 11. The jig 22 can be rotated together with the rotary table 11. That is, the fixed state of the lower jig 22 is maintained in that state unless the fixing bolt 24 is released, and no deviation occurs even in the rotation phase thereof.

Therefore, when the work W is fixed to the mounting surface 11a of the rotary table 11, the work W is first sandwiched between the protruding portion 21d of the upper jig 21 and the fitting portion 22d of the lower jig 22. Next, the upper jig 21 and the lower jig 22 are connected by a plurality of connecting bolts 23, and the upper jig 21, the work W, and the lower jig 22 are coaxially overlapped without a gap. Then, the lower jig 22 is fixed to the mounting surface 11a by the fixing bolt 24.

Alternatively, first, the lower jig 22 is fixed to the mounting surface 11a with the fixing bolt 24. Next, after fitting the work W to the fitting portion 22d of the lower jig 22, the protruding portion 21d of the upper jig 21 is brought into close contact with the upper end surface Wb of the work W, whereby the work W is brought into close contact with the upper jig 21. It is sandwiched between the protruding portion 21d of the above and the fitting portion 22d of the lower jig 22. Then, the upper jig 21 and the lower jig 22 are connected by a plurality of connecting bolts 23, and the upper jig 21, the work W, and the lower jig 22 are coaxially overlapped without a gap.

Therefore, whichever of the two fixing methods described above is adopted, the upper jig 21, the work W, and the lower jig 22 are coaxially overlapped with respect to the mounting surface 11a of the rotary table 11. , The work W can be pressed and fixed from the axial direction.

Next, a gear processing method using skiving processing will be described in detail with reference to FIGS. 4A to 4D and FIG.

First, as shown in FIG. 4A, the first work W is fixed to the mounting surface 11a of the rotary table 11 by using jigs 21 and 22 and bolts 23 and 24.

Next, the spindle 12 is tilted so that the cutter rotation shaft B is tilted with respect to the work rotation shaft C. That is, the spindle 12 is tilted so that the axis crossing angle between the cutter rotation axis B and the work rotation axis C becomes a predetermined angle according to the twist angle of the pinion cutter 13. As a result, the blade streak direction of the pinion cutter 13 coincides with the tooth streak direction of the work W.

Then, the work W is rotated around the work rotation axis C together with the jigs 21 and 22, and the pinion cutter 13 is rotated around the cutter rotation axis B. That is, the work W and the pinion cutter 13 are divided into the peripheral speed of the inner peripheral surface Wa, the peripheral speed of the inner peripheral surface 21a, the peripheral speed of the inner peripheral surface 22a, and the peripheral surface (blade portion) of the pinion cutter 13. Synchronously rotate so that the speed is equal.

Next, the pinion cutter 13 is provided with a notch in the radial direction and then a feed in the axial direction. That is, the work W, the lower jig 22, and the pinion cutter 13 are synchronously rotated to engage with each other, and the pinion cutter 13 is cut in the radial direction stepwise while the pinion cutter 13 is cut in the axial direction at each cutting position. Move from the top to the bottom.

As a result, as shown in FIG. 4B, the blade portion of the pinion cutter 13 cuts the inner peripheral surface Wa of the work W and the inner peripheral surface 22a of the lower jig 22, and the inner peripheral surface Wa and the inner peripheral surface Wa and the inner peripheral surface 22a are cut. The same tooth profile is formed on the peripheral surface 22a.

At this time, the work W is firmly fixed between the upper jig 21 and the lower jig 22 with good positioning accuracy by the tightening force of the connecting bolt 23 and the fitting to the fitting portion 22d. Therefore, the lower end surface Wc of the work W and the fitting portion 22d of the lower jig 22 are in close contact with each other without a gap. Therefore, when both the work W and the lower jig 22 are geared by the pinion cutter 13, burrs are suppressed on the lower end surface Wc, while burrs are generated on the lower end surface 22c.

Further, in the gear cutting operation of the pinion cutter 13, the cutting position (cutting amount) at each feeding does not change, so that the positional relationship in the radial direction between the pinion cutter 13 and the work W is constant. As a result, the dimensions of the tooth profile formed on the work W and the lower jig 22 are constant from the upper end surface Wb of the work W to the lower end surface 22c of the lower jig 22.

Then, when the gear cutting for the first work W is completed, only the fastening of the connecting bolt 23 is released, the upper jig 21 is removed, and then the first work W is replaced with the second work. Exchange for W. That is, without releasing the fastening of the fixing bolt 24, the lower jig 22 is still fixed, the connecting bolt 23 is released, the upper jig 21 is removed, and then the work W is removed. Replace processed products with unprocessed products. As a result, the rotation phase of the spindle 12 and the rotation phase of the rotation table 11 are kept in synchronization with each other. Therefore, even if the work W is replaced, the rotation phase of the pinion cutter 13 and the rotation phase of the lower jig 22 are maintained. The rotation phase is maintained in a rotation phase relationship that properly meshes with each other, and there is no change in the rotation phase relationship between them.

Next, as shown in FIG. 4C, the second work W is fixed to the mounting surface 11a of the rotary table 11 by using jigs 21 and 22 and bolts 23 and 24. After that, as shown in FIG. 4D, the same gear cutting operation as the gear cutting operation when the first work W described above is geared is performed. As a result, only the work W is cut by the pinion cutter 13.

That is, as shown in FIG. 4C, when the second work W is gear-cut, the lower jig 22 is already gear-cut, unlike the case where the first work W is gear-cut. Further, since the rotation phase of the lower jig 22 and the rotation phase of the pinion cutter 13 match, only the work W of the work W and the lower jig 22 is gear-cut. At this time, the pinion cutter 13 only meshes with the lower jig 22 that is maintained in the fixed state when the gear is cut together with the first work W, and does not cut the lower jig 22. .. As a result, the occurrence of burrs on the lower end surface Wc is suppressed, and no burrs are generated on the lower end surface 22c.

Then, even when the third and subsequent works W are gear-cut, the replacement of the work W and the gear-cutting to the work W are alternately performed in the same manner as in the case of gear-cutting the second work W. .. That is, as shown in FIGS. 4C and 4D, even when the third and subsequent work Ws are geared, the upper and lower pair of upper jigs 21 and lower jigs are used as jigs for fixing the work Ws. Only 22 will be used, and the upper jig 21 will be attached and detached each time the work W is replaced, but the lower jig 22 will be fixed as it is even after being tooth-cut together with the first work W. Continue to be used while maintaining the state (rotational phase).

Here, as described above, if the plurality of workpieces W are continuously cut by one pinion cutter 13, the blade portion of the pinion cutter 13 is worn and the sharpness thereof is lowered. In such a case, it is necessary to replace the worn pinion cutter 13 with a new non-wear pinion cutter 13.

However, if the pinion cutter 13 is replaced, the rotation phase of the replaced new pinion cutter 13 and the rotation phase of the gear-cut lower jig 22 are deviated from each other. If only the work W is attempted to be geared in such a state, even the lower jig 22 that does not require gear cutting will be geared, and in some cases, a large burr may be generated on the lower end surface Wc of the work W. There is a risk of doing so. Therefore, when the pinion cutter 13 is replaced, it is necessary to replace the lower jig 22 as well, which causes a decrease in productivity.

Therefore, in order to solve the above problem, when the pinion cutter 13 is replaced, the rotation phase alignment between the pinion cutter 13 and the lower jig 22 is performed prior to the gear cutting by the replaced new pinion cutter 13. I try to do it. That is, the rotational phase is adjusted between the replaced pinion cutter 13 and the lower jig 22 that has already been geared so that the lower jig 22 has a rotational phase relationship that appropriately meshes with each other.

Specifically, as shown in FIG. 5, first, the plurality of workpieces W are fixed to the mounting surface 11a of the rotary table 11 by using jigs 21 and 22 and bolts 23 and 24, and a pinion cutter is used. Replace 13 with a new one.

Next, while rotating the pinion cutter 13 around the cutter rotation axis B, the rotation phase thereof is detected by the sensor 14. The sensor 14 detects the circumferential position of the pinion cutter 13 around the cutter rotation axis B in the blade portion or the blade groove, and can obtain the rotation phase of the pinion cutter 13 based on the detection result. .. On the other hand, since the lower jig 22 is fixed from the time when the first work W is geared, the rotation phase of the lower jig 22 is the first geared work. It remains consistent with the rotation phase of W.

Then, the pinion cutter 13 is rotated around the cutter rotation axis B so that the rotation phase of the pinion cutter 13 matches the rotation phase of the lower jig 22. That is, the rotation phase of the pinion cutter 13 is adjusted so that the blade portion and the blade groove of the pinion cutter 13 and the tooth groove and the tooth portion of the lower jig 22 can be appropriately meshed with each other.

Next, the work W, the lower jig 22, and the pinion cutter 13 are synchronously rotated to engage with each other, and the pinion cutter 13 is cut in the radial direction stepwise while the pinion cutter 13 is cut in the axial direction at each cutting position. Move from the top to the bottom. As a result, the pinion cutter 13 cuts only the work W, while meshing with the lower jig 22 without cutting the teeth.

That is, even when the pinion cutter 13 is replaced, the lower jig 22 has already been geared, and the rotation phase of the lower jig 22 and the rotation phase of the pinion cutter 13 are matched in advance. Of the work W and the lower jig 22, only the work W is gear-cut. At this time, the pinion cutter 13 only meshes with the lower jig 22 that has already been tooth-cut, and does not cut the lower jig 22. As a result, the occurrence of burrs on the lower end surface Wc is suppressed, and no burrs are generated on the lower end surface 22c.

In the above-described embodiment, the case where the gear processing method and the gear fixing device according to the present invention are applied to the internal gear gear cutting method and the internal gear fixing device using skiving processing will be described. It can be applied to an internal gear gear cutting method and an internal gear fixing device for processing an internal gear using a shaving machine, and an external gear gear cutting method and an external gear fixing device for processing an external gear using a hob machine. Further, even if the workpiece is either an internal gear or an external gear, those gears may be spur gears or helical gears. Further, when the workpiece is an internal gear, a barrel-shaped screw-shaped tool may be used as the cutting tool instead of the gear-shaped tool.

Therefore, when cutting the teeth of the plurality of workpieces W, the pair of upper and lower jigs 21 and the lower jig 22 can be continuously used without being replaced. Further, even if the work W is fixed by the upper jig 21 and the lower jig 22, these do not affect the gear cutting operation of the pinion cutter 13, and the gear cutting operation of the pinion cutter 13 may be complicated. There is no. Therefore, it is possible to easily suppress the occurrence of burrs on the lower end surface Wc of the work W while suppressing an increase in manufacturing cost.

Further, even when the pinion cutter 13 is replaced, the pinion cutter 13 is rotated so that the replaced pinion cutter 13 and the gear-cut lower jig 22 have a rotational phase relationship in which they can mesh with each other. By matching the phase with the rotation phase of the lower jig 22, it is possible to eliminate the need to replace the lower jig 22.

On the other hand, by forming the protruding portion 21d on the lower end surface 21c of the upper jig 21, the work W can be pressed with a large pressing force, so that the work W can be firmly fixed. Further, by fitting the work W to the fitting portion 22d formed on the lower jig 22, the work W can be positioned with high accuracy in the radial direction. As a result, it is possible to prevent a decrease in the processing accuracy of the work W. Further, by opening the bolt hole 21e into which the connecting bolt 23 for connecting the upper jig 21 and the lower jig 22 is inserted adjacent to the protruding portion 21d, the fastening force by the connecting bolt 23 is increased. , It can be efficiently converted into the pressing force by the protruding portion 21d.

11 Rotating table 11a Mounting surface 12 Main shaft 13 Pinion cutter 14 Sensor 21 Upper jig 21a Inner peripheral surface 21b Upper end surface 21c Lower end surface 21d Protruding part 21e Bolt hole 22 Lower jig 22a Inner peripheral surface 22b Upper end surface 22c Lower end surface 22d Fitting Part 23 Connecting bolt 24 Fixing bolt W Work Wa Inner peripheral surface Wb Upper end surface Wc Lower end surface Wd Outer peripheral surface B Cutter rotation axis C Work rotation axis

Claims (5)

In a gear machining method in which a work piece is geared by the tool by giving an axial feed of the work piece to the tool while rotating the work piece and the tool.
The end face on the downstream side in the feed direction of the work piece of the first product is brought into surface contact with the lower jig.
The work piece of the first product and the lower jig are coaxially overlapped with each other.
The work piece of the first product is pressed and fixed toward the fixed lower jig.
Both the work piece of the first product and the fixed lower jig are gear-cut with the tool.
The fixed state of the lower jig when the teeth are cut together with the work piece of the first product is maintained as it is.
The end face on the downstream side in the feed direction of the work piece after the next product is brought into surface contact with the lower jig in which the fixed state is maintained.
The work piece after the next product and the lower jig maintained in the fixed state are coaxially overlapped.
The work piece after the next product is pressed and fixed toward the lower jig in which the fixed state is maintained.
Gear cutting operation when the workpiece of the first product is geared with respect to the tool while maintaining a rotational phase relationship that allows meshing between the tool and the lower jig that is maintained in the fixed state. A gear machining method characterized in that only the workpiece after the next product is geared by giving the same gear cutting operation as in the above. In the gear processing method according to claim 1,
If the tool is replaced when cutting the workpiece after the next product,
Prior to gear cutting with the replaced tool
The rotation phase of the replaced tool is changed so that the exchanged tool and the lower jig in which the fixed state is maintained have a rotational phase relationship that allows meshing with the lower jig. A gear processing method characterized by matching with the rotation phase of a tool. In the gear processing method according to claim 1 or 2,
The work piece of the first product or the work work of the next product or later is coaxially formed from both sides in the axial direction by the upper jig and the lower jig arranged on the upstream side in the feed direction from the lower jig. A gear machining method, characterized in that the tool is sandwiched and fixed in a gear, and the tool cuts the work piece of the first product or the work piece of the next product or later without cutting the upper jig. When the work piece is geared by the tool by giving the work piece an axial feed to the work piece while rotating the work piece and the tool, the work piece is said to be the work piece. In the gear fixing device that fixes
A rotary table rotatably supported around the axis of the workpiece and
The peripheral surface that is fixed to the rotary table and comes into surface contact with the end surface on the downstream side in the feed direction of the workpiece and is geared with the tool together with the peripheral surface of the workpiece, or the workpiece is toothed. A lower jig having a tooth profile that meshes with the tool immediately after cutting,
An upper jig, which is arranged on the upstream side in the feed direction with respect to the lower jig, and fixes the workpiece coaxially with the lower jig from both sides in the axial direction.
A protrusion that projects from the end surface on the downstream side in the feed direction of the upper jig toward the downstream side in the feed direction and presses the end surface on the upstream side in the feed direction of the workpiece.
A connecting bolt that connects the upper jig and the lower jig in the axial direction,
A bolt hole that penetrates the upper jig in the axial direction and into which the connecting bolt is inserted is provided .
The bolt holes, the gear locking device according to claim Rukoto is opened adjacent to the protuberant portion. In the gear fixing device according to claim 4,
A gear fixing device formed on the lower jig and fitted with the workpiece to be provided with a fitting portion for positioning the workpiece in the radial direction.

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