JP3412507B2 - Gear honing machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear honing machine used for finishing a gear, and is capable of machining under a relatively large cutting allowance while maintaining the required surface roughness accuracy of the tooth surface. To improve the gear honing machine.

[0002]

2. Description of the Related Art When manufacturing a high-precision gear, for example, a helical gear, it is generally necessary to perform a two-step finishing process of tooth profile grinding (hard finisher) and honing after heat-treating followed by heat treatment. It is said that Tooth profile grinding is a grinding process with a relatively large cutting allowance (removing allowance) using a screw-shaped grindstone for the purpose of removing heat treatment distortion, whereas honing is a surface roughness of the tooth surface. High-speed grinding with a relatively small cutting allowance to ensure accuracy.

[0003]

There is a demand for a honing machine capable of substantially performing the above tooth profile grinding and honing in one step from the standpoint of integrating the steps of helical gear machining. In order to meet this demand, it is necessary to rotate the grindstone and the work at high speed and synchronize them with each other with high precision, but the conventional structure cannot cope with them. For example, according to the specifications of the existing grindstone and work, when the grindstone rotates at 1,000 rpm, the work needs to be rotated at about 6,000 rpm, but the required performance cannot be satisfied particularly in terms of synchronization accuracy.

More specifically, FIGS.
1 shows a schematic structure of a conventional representative gear honing machine shown in Japanese Patent No. 58591, for example, a shaft S
A workpiece gear (helical gear) W integral with the above is supported by a chuck 2 on the headstock 1 side, a head center 3 and a tail center 5 on the tailstock 4 side by both sides, and the workpiece gear W and an internal gear While meshing with the grindstone 7, the work gear W is synchronously rotated by the spindle motor 6 and the grindstone 7 by the grindstone drive motor 16, respectively, and the work gear W and the grindstone 7 are rotated as if they were a gear pair. By giving a cut feed to 7, the tooth surface of the gear W to be processed is ground and finished.

Here, the grindstone 7 in the shape of the internal gear is the tightening ring 1.
It is fixedly supported by the grindstone holder 8 by 9, 20 and the grindstone holder 8 is rotatably supported by the housing 9 via a bearing 10. Further, the housing 9 is integrally connected to the slide base 11, and together with the slide base 11, forms a grindstone 12. Then, the grindstone 12 is fed by a feed motor 13 and a ball screw 14 to move forward and backward.

Further, while a chain sprocket 15 is integrally formed on the outer circumference of the grindstone holder 8, a chain 18 is provided between the chain sprocket 15 on the grindstone holder 8 side and the chain sprocket 17 on the grindstone drive motor 16 side. The grindstone 7 is wound around and the grindstone 7 is the grindstone drive motor 1.
6 drives to rotate via a chain 18.

However, since the grindstone 7 is a rotary drive system using the chain 18 (which may be gear transmission), the bending and backlash of the chain 18 causes
Even if the grindstone 7 and the gear W to be processed are synchronized, the synchronization error becomes large, and the intended purpose cannot be achieved.

The present invention has been made in view of the above problems, and a gear honing machine capable of honing under a larger cutting allowance while ensuring the surface roughness accuracy of the gear to be processed. Is to provide.

[0009]

According to a first aspect of the present invention, there is provided a wheel head having a head center and a tail center both supporting a gear to be machined and an internal gear-shaped grindstone externally fitted to the gear to be machined. And, in the state where the gear to be processed and the grindstone are meshed with each other, while simultaneously rotating the gear to be processed and the grindstone by separate drive motors, to give a cutting feed in the diametrical direction of the gear to be processed to the grindstone base. Is a gear honing machine configured to perform honing on the gear to be processed, wherein the grindstone head is rotatably supported by a drive gear directly driven by a grindstone driving motor and an inner circumference. The whetstone is mounted on the whetstone and the whetstone holder is provided with a driven gear on the outer periphery, and the whetstone base body is engaged with both the drive gear and the driven gear. Is rotatably supported, drive
Backlash for both gear and driven gear
It is equipped with an idle gear that can be adjusted . Moreover
Control the rotation of the grindstone drive motor and workpiece drive motor.
The motor control means to control is the grindstone and the work to be rotated synchronously.
Of which, the rotation of the grindstone is the master side, and the rotation of the workpiece is the slave
As a side, in order to positively give a phase difference to the rotation of both,
In the low speed rotation area on the master side, it is delayed to the rotation phase on the slave side.
In the high-speed rotation area on the master side, the slave side
The rotation speed on the master side is set so that the rotation has a phase lead.
Rotation phase that corrects the rotation command value on the slave side according to
It is characterized by having a difference control means .

According to a second aspect of the invention, the idle gear in the first aspect of the invention is rotatably supported by the gear holder, and the mounting position of the gear holder with respect to the wheel head main body can be adjusted. It has a feature.

The invention according to claim 3 is characterized in that the mounting position of the gear holder with respect to the grinding wheel base body of the invention according to claim 2 is adjustable in three dimensions.

[0012]

[0013]

[0014]

Therefore, in the invention described in claims 1 to 3, the main shaft (spindle) on the headstock side, which supports the gear to be processed, is rotated via the transmission gear without being directly driven by the motor. 6,000 rpm by driving to increase the speed by the speed change gear
High speed rotation is possible.

On the other hand, regarding the driving of the grindstone, an idle gear is interposed between a drive gear driven by a motor and a driven gear on the side of the grindstone holder on which the grindstone is mounted, and the grindstone is rotated through this idle gear. To drive.
At that time, by adjusting the position of the idle gear with respect to the main body of the whetstone, the backlash between the drive gear and the driven gear can be minimized, and the work and the whetstone can be precisely moved while rotating the work at high speed. Can be synchronized. This means that it is possible to machine under a larger cutting allowance while maintaining the surface roughness accuracy of the tooth surface of the gear to be machined.

[0017] In particular, positively variably controlling the rotational position phase between the grinding wheel and the workpiece to be rotated synchronization by motors control means
Doing, it is possible to have a phase lead lag or phase synchronous rotation of both the person. The phase lag and phase lead referred to here indicate whether the resistance at the contact part between the workpiece that is rotating synchronously and the grindstone is large or small, and by adjusting the degree of this, larger scraping while maintaining good surface roughness of the tooth surface. It is possible to realize honing processing in the generation.

[0018] That is, while the rotation of the abrasive stones can not chipping only machining allowance required grinding force is reduced between the workpiece as becomes faster, the surface roughness precision rotation of the grinding wheel is increased when the slower grinding resistance Paying attention to the fact that the rotation speed of the grindstone decreases, the rotation speed of the workpiece on the slave side is positively variably controlled according to the rotation speed of the master side. By doing so, it becomes possible to further achieve both the machining with emphasis on the surface roughness of the tooth surface and the machining with emphasis on the cutting allowance.

[0019]

According to the present invention, the idle gear is interposed between the drive gear and the driven gear for rotationally driving the grindstone, and the backlash of the gear train is eliminated by the idle gear itself. Since it can be adjusted by the backlash adjustment function of, the backlash can be minimized while rotating the grindstone at high speed. This enables high-speed and high-accuracy synchronization between the grindstone and the workpiece, which was previously difficult, and enables honing under a larger cutting allowance while maintaining the surface roughness accuracy of the gear to be processed. As a result, there is an effect that the finishing of the gear, which conventionally had to be performed in two steps, can be performed in one step. In addition, the grindstone and the workpiece can rotate synchronously at high speed and with high accuracy.
While positively controlling the rotational phase difference between the two
Because of this, the phase difference between the work and the grindstone
You can adjust the resistance at the contact part of
Layer and surface roughness accuracy while maintaining a large cutting allowance
This allows for efficient processing.

[0020]

[0021]

[0022]

1 and 2 are views showing a preferred embodiment of the present invention, in which a shaft portion S and a gear to be processed (helical gear) are shown.
The work W consisting of G and one end has a headstock 2
It is supported by the head center 22 and the chuck 23 on the first side, and the other end is on the tail center 2 side on the tailstock 24 side.
Work drive motor (spindle motor) 2 supported by 5
It is rotationally driven by 6.

On the outer periphery of the work W, an internal gear-shaped grindstone 27 that meshes with the gear G to be processed is provided so as to be supported by a grindstone holder 28, and the grindstone holder 28 is connected to a housing via a bearing (not shown). It is rotatably supported by 29. The housing 29 constitutes a grindstone base 30 together with a slide base (not shown). The grindstone base 30 has a cutting feed in a direction (direction of arrow A) substantially orthogonal to the work shaft center and an oscillating direction (work shaft) indicated by arrow B. It is designed so that a feed in the (heart direction) is given.

FIG. 3 is a front view of the head stock 21, FIG. 4 is a horizontal sectional view of the head stock 21, and FIG. 5 is a left side view of FIG.
Shows the P direction arrow view in FIG. 3, respectively.

As shown in FIGS. 3 to 6, the headstock 2
1 is a spindle (spindle) 32 through a bearing 31
Is rotatably supported, and at the tip of the spindle 32, a collet chuck 23 and a head center 22 for supporting the work W are provided.
A driven gear (helical gear) is provided at the rear end of the spindle 32.
33 is attached. A drive gear 35 having a larger diameter than that of the driven gear 33 is fixed to the output shaft 34 of the work drive motor 26 mounted on the head center 21. Reference numeral 36 denotes a dynamic damper (inertia damper) fixed coaxially with the drive gear 35. Therefore, the work drive motor 26
Of the spindle 32 via the gear trains 35 and 33
Is designed to rotate at an increased speed.

An input shaft of a rotary encoder 37 for synchronization is fixed to the rear end of the spindle 32, and the rotary encoder 37 detects the rotational angle position of the work W.

The work driving motor 26 is fixed to the head stock 21 via a motor base 38, and the head stock 21 is provided with an adjuster block 39 adjacent to the motor base 38. Adjustment bolts 40, 4 are provided on the adjuster block 39.
1 is provided, and the position of the work drive motor 26 with respect to the head stock 21 can be adjusted by rotating the adjusting bolts 40 and 41. That is, by adjusting the position of the work driving motor 26 toward and away from the spindle 32 by operating the adjusting bolts 40 and 41, the backlash at the meshing portion of the drive gear 35 and the driven gear 33 is adjusted. You can do it.

On the other hand, FIG. 7 is a front view of the grindstone base 30,
8 is a right side view of FIG. 7, FIG. 9 is a left side view of FIG. 7, and FIG.
A grindstone holder 28 is rotatably supported via bearings as in the conventional structure shown in FIG. 11, and an internal gear-shaped grindstone 27 is attached to the inner circumference of the grindstone holder 28 by a tightening ring (not shown). Fixed. A driven gear (helical gear or spur gear) 42 is integrally formed on the outer peripheral surface of the grindstone holder 28.

A grindstone drive motor 43 is fixed to the side surface of the housing 29.
Drive gear (helical gear or spur gear) on the output shaft of
The drive gear 44 and the driven gear 42 mesh with each other via an idle gear 45. Then, for example, the grindstone 27 with a reduction ratio of 1/3
Is driven to rotate.

The idle gear 45 is rotatably supported by a gear holder 46 which is detachably attached to the housing 29, and the gear holder 46 is fixed to the housing 29 by a bolt 48 via a spacer 47. The position can be adjusted in a direction orthogonal to the rotation center of each gear 44, 45, 42 by rotating the adjustment bolt 49 attached to the gear holder 46.

The housing 29 has a gear holder 46.
To be adjacent to the pair of adjuster blocks 50,
51 are arranged. These adjuster blocks 5
0 and 51 are basically the same as those shown in FIGS. 4 and 5, and the position of the gear holder 46 with respect to the housing 29 is set by rotating the adjusting bolts attached to the adjuster blocks 50 and 51. The adjustment bolts can be adjusted in the axial direction. That is, the gear holder 4 supporting the idle gear 45
The position of 6 can be adjusted in three orthogonal directions with respect to the housing 29, whereby the backlash at the meshing portion of the drive gear 44, the idle gear 45, and the driven gear 42 can be finely adjusted. .

A rotary encoder 53 for synchronization is mounted via a gear box 52 at a position facing the grindstone driving motor 43 with the housing 29 interposed therebetween. As shown in FIG. 10, the input shaft of the rotary encoder 53 is configured to rotate at the same rotational speed as the rotational speed of the grindstone 27 via the speed change gear trains 54 and 55 in the gear box 52.
The rotary encoder 53 detects the rotational angle position of the grindstone 27.

As shown in FIGS. 7 and 9, adjuster blocks 56 and 57 similar to those described above are also arranged around the gear box 52, and are attached to these adjuster blocks 56 and 57. The gear box 52 for the housing 29 is operated by operating the adjusting bolt.
By finely adjusting the position of, the backlash in the meshing portion of the transmission gear trains 54, 55 can be adjusted. As a result, the influence of backlash in the transmission gear trains 54 and 55 can be avoided, and the rotary encoder 53 can detect the rotational angle position of the grindstone 27 more accurately.

FIG. 10 is a block circuit diagram of the control system of the gear honing machine shown in FIGS. 3 to 9. In the controller 57 as the control means, the grindstone drive motor 43 is the master side and the work drive motor 26 is the slave side. As such, the rotation of each motor 43, 26 is controlled.

That is, the controller 57 controls the grindstone 27.
Is supplied from the speed control unit 58 to the servo amplifier 59 to rotate the grindstone 27 by the grindstone driving motor 43, while a synchronous rotation command is supplied from the position control unit 60 to the servo amplifier 61 to work W by the work driving motor 26. In order to synchronize and follow the rotation of the work W with the rotation of the grindstone 27, the rotational position feedback signal of the grindstone 27, which is the output of the rotary encoder 53, is corrected by a correction amount described later. While being monitored by the calculation unit 63 and a correction amount corresponding thereto is added as positive feedback to the adder 64 at the previous stage of the position control unit 60, the work W which is the output of the other rotary encoder 37.
The rotational position feedback signal of 1 is added as negative feedback to the adder 64 through the speed increasing ratio calculation unit 62.

The controller 57 is provided with a correction amount calculation unit 63 which functions as a rotation phase difference control means, and the correction amount calculation unit 63 moves to the slave side according to the rotation speed of the grindstone 27 which is the master side. The correction amount of the position command is added to the adder 64 as positive feedback to correct the rotational position command of the work W.

Therefore, according to the present embodiment, FIG.
In addition, as shown in FIG. 10, among the workpieces W supported by the head stock 21 and the tail stock 24, the workpiece gear G and the grindstone 27 are engaged with each other, and then the workpiece W is driven by the work drive motor 26. Thus, while the grindstone 27 is synchronously rotated by the grindstone drive motor 43, while the grindstone base 30 is being oscillated in the axial direction of the work W, the cutting feed is applied substantially in the direction perpendicular to the axis of the workpiece W, so that the gear to be machined as in the conventional case. The G and the grindstone 27 rotate as if they were in the relationship of a pair of gears, and the tooth surfaces on the gear G to be processed are ground and finished due to the sliding contact between their tooth surfaces.

In this case, as shown in FIG. 10, since the work W is rotationally driven by the work drive motor 26 through the speed increasing gear trains 35 and 33, the work W is 6,000 rp.
It is possible to rotate at a high speed of about m, and by adjusting the backlash between the gear trains by operating the adjust bolt attached to the adjuster block 39, it is possible to achieve high speed rotation while achieving the low backlash. realizable.

The above is the same for the grindstone base 30 side. As shown in FIG. 1 and FIG.
Reference numeral 7 is a speed reduction gear train 44, 4 composed of a drive gear 44, an idle gear 45, and a driven gear 42.
Although it is rotationally driven via 5, 42, the gear holder 46 supporting the idle gear 45 can adjust its position in the three-dimensional direction with respect to the housing 29 by the operation of the adjusting bolt as described above. By finely adjusting the position of the gear holder 46, the idle gear 4
It is possible to achieve low backlash in the meshing portion of the gear 5, the drive gear 44, and the driven gear 42.

At the same time, as shown in FIG. 10 in addition to FIG.
The input of the rotary encoder 53 attached to the grindstone drive motor 43 is also the speed change gear trains 54 and 55 for deceleration.
Although it is input via the adjuster blocks 56 and 57, low backlash can be achieved even at the meshing portions of the transmission gear trains 54 and 55 by operating the adjusting bolts attached to the two adjuster blocks 56 and 57.

Therefore, for example, the grindstone 27 is set to 1,000.
Even if the work W is rotationally driven at about rpm and about 6,000 rpm, the work W and the grindstone 27 can be accurately synchronized without being affected by the backlash and the like.

On the other hand, as described above, the correction amount calculation unit 63 in the controller 57 shown in FIG. 10 corresponds to the workpiece W on the slave side in accordance with the rotational speed of the grindstone 27 on the master side.
Has a function of positively and variably controlling the rotational position command value, and the correction amount calculation unit 63 has a table as shown in Table 1.

[0043]

[Table 1]

That is, the higher the rotational speed of the grindstone 27, the lower the grinding resistance with the work W, and even if a predetermined cutting feed is given, it is not always possible to cut off the necessary cutting allowance. In addition, as the rotational speed of the grindstone 27 becomes slower, the grinding resistance increases and the surface roughness of the tooth surface of the gear G to be processed deteriorates.

Therefore, in the present embodiment, the rotational speed of the grindstone 27 on the master side is monitored, and the rotational speed of the workpiece W on the slave side is positively variably controlled according to the rotational speed of the grindstone 27. , For example, the rotational speed of the grindstone 27 is in the low speed range (0
If the rotation speed of the grindstone 27 is in the normal (steady) speed range (300 to 800 rpm), a predetermined negative correction amount is added to the adder 64. Do not add the correction amount to the device 64. Furthermore, the rotational speed of the grindstone 27 is in the high speed range (800 rpm or more)
In the case of, the predetermined amount of positive (plus) correction amount is added to the adder 64. By doing this, the grindstone 27
When the rotation speed of the workpiece W is high, the workpiece W is likely to rotate synchronously with the rotation of the grindstone 27, so that grinding resistance is added to the contact portion between the workpiece W and the grindstone 27, and the necessary cutting allowance is added. It will only be possible to remove it reliably. On the contrary, when the rotation of the grindstone 27 is low, the synchronous rotation of the work W tends to be delayed with respect to the rotation of the grindstone 27, so that the grinding resistance at the contact portion between the work W and the grindstone 27 decreases. As a result, the surface roughness on the tooth surface of the processed gear G is improved.

As described above, according to the present embodiment, the grindstone 27 and the work W are not affected by the backlash due to the low backlash of the speed change gear train in the grindstone drive system and the work drive system. Can be synchronously rotated at high speed and with high accuracy, and as a result, a relatively large cutting allowance can be achieved while maintaining the surface roughness accuracy of the tooth surface of the gear G to be processed, which has been considered difficult in the past. Gear honing with and is possible.

[Brief description of drawings]

FIG. 1 is a schematic configuration explanatory view showing an embodiment of a gear honing machine according to the present invention.

FIG. 2 is an explanatory view showing a relationship between a work and a grindstone in FIG.

FIG. 3 is a front view showing details of the head stock shown in FIG.

FIG. 4 is a horizontal sectional view of FIG.

5 is a left side view of FIG.

FIG. 6 is a view on arrow P in FIG.

7 is a plan view of the grindstone base shown in FIG. 1. FIG.

8 is a right side view of FIG. 7.

9 is a left side view of FIG. 7.

10 is a block circuit diagram of a control system of the honing machine shown in FIG.

FIG. 11 is an explanatory view of the configuration of a conventional honing machine.

12 is a cross-sectional explanatory view of the grindstone base shown in FIG.

[Explanation of symbols]

21 ... Headstock 22 ... Head center 23 ... Collet chuck 24 ... Tailstock 25 ... Tail center 26 ... Work drive motor 27 ... Whetstone 28 ... Whetstone holder 29 ... Housing 30 ... Whetstone stand 37 ... Rotary encoder 39 ... Adjuster block 42 ... Driven gear 43 ... Whetstone drive motor 44 ... Drive gear 45 ... Idle gear 46 ... Gear holder 50, 51 ... Adjuster block 53 ... Rotary encoder 57 ... Controller 63 ... Correction amount calculation unit (rotational phase difference control means) G: Gear to be processed (helical gear) W ... work

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-10-94920 (JP, A) JP-A-9-57624 (JP, A) JP-A-56-62722 (JP, A) JP-A-3- 264238 (JP, A) JP-A-3-142129 (JP, A) Actual opening 1-16-1602 (JP, U) Actual opening 61-7650 (JP, U) Actual opening 61-40547 (JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B23F 19/05 B23F 23/12 B23Q 5/56 F16H 57/12

Claims (3)

(57) [Claims] 1. A head center and a tail center that both-ends and supports a gear to be processed, and a whetstone base having a grindstone in the shape of an internal gear that is externally inserted to the gear to be processed, and the gear to be processed and the whetstone are meshed with each other. In this state, the gear to be machined and the grindstone are synchronously rotated by separate drive motors, respectively, and the honing is applied to the gear to be machined by giving the grinding wheel base a diametrical cutting feed to the gear to be machined. A gear honing machine, wherein the grindstone base is rotatably supported by a drive gear directly driven by a grindstone drive motor, and the grindstone body is rotatably supported, and the grindstone is mounted on the inner periphery and a driven gear is mounted on the outer periphery. And a grindstone holder provided with a drive gear that is rotatably supported by the grindstone base body so as to mesh with both the drive gear and the driven gear.
Adjustment of backlash for both driven gear and driven gear
And an idle gear that can be adjusted to control the rotation of the grindstone drive motor and the work drive motor.
The motor control means for rotating the grinding wheel and the workpiece
Rotation of the grinding wheel is on the master side, and rotation of the work is on the slave side.
Then, in order to positively have a phase difference in both rotations, the mass
In the low speed rotation area on the rotor side, there is a delay in the rotation phase on the slave side.
In the high speed rotation area on the master side, rotation on the slave side
Depending on the number of revolutions on the master side,
Rotation phase difference control that corrects the rotation command value on the slave side
A gear honing machine characterized by having control means . 2. The gear honing machine according to claim 1, wherein the idle gear is rotatably supported by a gear holder, and a mounting position of the gear holder with respect to the wheel head main body is adjustable. 3. The gear honing machine according to claim 2, wherein the mounting position of the gear holder with respect to the main body of the grinding wheel is adjustable in three dimensions.