JPH07124820A - Gear finishing device - Google Patents

Abstract

PURPOSE:To process accurately while rotating at a high speed as the driving side to a gear to be processed, by forming a rotary bearing with three rotary rollers arranged along the periphery of an inner tooth gear form grinding wheel at equal intervals. CONSTITUTION:When a gear to be processed W is driven to rotate through a driving motor 6, a grinding wheel body 13 is also rotated together with the rotation of the gear to be processed W. By the sliding between the gear face of the gear to be processed W and the gear face of a grinding wheel 16 in the relative rotation, a honing process is carried out. Since the gear to be processed W whose diameter is smaller than that of the grinding wheel body 13 is rotated by the driving motor 6 in this case, the rotation is carried out at a speed higher than the conventional device, so as to improve the machining capacity. And by a rotary bearing which consists of three rotary rollers 17, the rotating friction is reduced, and the grinding can be finished accurately without generating an unvalance of the gringing amount. Furthermore, the engaging part of the grinding wheel body 13 and the machined gear W is positioned at the central part of two rollers 17, in this case, and the basic function as a bearing is increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear finishing device for finishing a tooth surface of a gear to be processed by relatively rotating a gear to be processed and an internal gear-shaped honing grindstone.

[0002]

2. Description of the Related Art Conventionally, as honing for finishing a tooth surface of a gear with high accuracy, there is known an apparatus for finishing by rotating an internal gear-shaped honing grindstone and a gear to be processed relative to each other. The general form of such a device is that a gear to be rotatably supported is meshed with an internal gear-shaped honing grindstone, and the internal gear-shaped honing grindstone is rotatably driven by a drive motor to be processed. The gear is driven to rotate to finish the tooth surface.

[0003]

However, in the conventional device, since the internal gear toothed grindstone is rotationally driven by the drive motor, there is a limit to the processing capacity. That is,
It is necessary to speed up the rotation of the grindstone in order to improve the processing ability, but the grindstone has a large diameter, so that the number of rotations is limited.

[0004]

Therefore, in order to increase the relative rotational speed and improve the machining capacity, the present invention engages a gear to be machined with an internal gear-shaped grindstone borne by a rotary bearing portion, and drives means. Thus, the gear to be processed is rotated. The rotary bearing portion is composed of three rotary rollers arranged at equal intervals along the outer circumference of the internal gear-shaped grindstone. Then, a groove portion corresponding to the outer peripheral surface shape of the internal gear-shaped grindstone was formed on the outer peripheral surface of the rotating roller. Further, the bearings in the radial direction and the thrust direction of the rotary bearing portion are composed of hydrostatic bearings.

[0005]

By rotating the gear to be processed by the driving means, it is possible to rotate at a higher speed and the processing capacity is improved. At this time, if the rotational friction resistance of the internal gear toothed wheel that is rotated is large, the frictional force between the advancing front side tooth surface of the gear to be processed and the grindstone also becomes greater on the rear side tooth surface than the friction force, and grinding There is a difference in quantity. Therefore, it is necessary to reduce the rotational frictional resistance force in order to make the rotation smooth, but the three-point support by the rotating roller allows the internal gear-shaped grindstone to roll lightly. The groove formed on the outer peripheral surface of the rotating roller makes the rotation support smoother. Further, by using a hydrostatic bearing, the effect of similarly reducing the rotational friction resistance force can be obtained.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a gear finishing device of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic plan view of the gear finishing apparatus, FIG. 2 is a side view of the same, FIG. 3 is a sectional view of an essential part, and FIG. 4 is a sectional view taken along the line AA of FIG.

The gear finishing apparatus of the present invention comprises a table 2 movable on the bed 1 in the feed direction, and the table 2.
Of the headstock 3, a drive motor 6 connected to the extended end of the spindle 4 of the headstock 3, a center stand 7 standing up from the other end of the table 2, and a forward / backward movement to and from the center stand 7. A center shaft 8 provided and a grindstone support 10 protruding laterally toward an intermediate portion between the headstock 3 and the center base 7 are provided, and the main shaft 4 and the center shaft 8 form a shaft center of the gear W to be processed. It is clamped so that it can be held.

The grindstone support 10 is movable in the direction orthogonal to the axial direction of the main shaft 4 by, for example, a cylinder unit 11, and a ring-shaped grindstone body 13 provided with an internal gear is provided therein. Has been.

Then, for example, in a state where the grindstone support 10 is retracted, a gear W to be machined is set between the main shaft 4 and the center shaft 8 and clamped by sandwiching both shafts 4 and 8 and then the grindstone support 10 To engage the gear W to be machined with the grindstone body 13, and the drive motor 6 rotates the gear W to be machined at high speed to rotate the grindstone body 13 and grind the meshing tooth surface.

Therefore, in such an apparatus, unless the rotational frictional resistance of the grindstone 13 is reduced as much as possible and it is not rotated smoothly, a difference in the frictional force before and after the tooth surface occurs and an unbalance occurs in the grinding amount. Therefore, this device adopts the structure of the rotary bearing portion as shown in FIGS. 3 and 4.

That is, as shown in FIGS. 3 and 4, the grindstone body 13 includes a ring-shaped spindle 14 and a ring-shaped grindstone 16 attached to the inner peripheral surface of the spindle 14 via a grindstone holder 15. Internal teeth are formed on the inner surface of the grindstone 16.

Then, as shown in FIG. 4, the spindle 1
The cross-sectional shape of No. 4 is a middle-height shape in which the central portion in the width direction has a large diameter.

The rotation bearing of the grindstone body 13 is carried out by three rotation rollers 17 arranged at equal intervals along the outer circumference of the spindle 14.

That is, the rotary rollers 17 are provided with a roller shaft 19 fixed to a housing 18 integrated with the grindstone support 10 and a roller 20 rotatable with respect to the roller shaft 19. On the outer peripheral surface, a groove 20a is provided in the center portion in the width direction so as to match the contour shape of the outer peripheral surface of the spindle 14.

In the present apparatus having the above-mentioned configuration,
When the processed gear W is rotationally driven via the drive motor 6,
The grindstone body 13 is also rotated along with the rotation of the gear W to be processed, and the honing is performed by the slip between the tooth surface of the gear W to be processed and the tooth surface of the grindstone 16 at the time of relative rotation. Since the work gear W having a small size is rotated by the drive motor 6, it can be rotated at a higher speed than the conventional one, and the processing capacity is improved.

Further, the rotary bearing portion composed of the three rotary rollers 17 reduces rotational frictional resistance, and the grinding amount can be accurately finished without imbalance.

At this time, as shown in FIG.
3 and the gear W to be processed are connected to each other by two rotary rollers 17,
It is located at the center of 17. With such an arrangement, the basic function of the bearing, that is, the function of ensuring rigidity or preventing runout is further enhanced.

Next, an embodiment in which the rotary bearing portion has a hydrostatic bearing structure will be described with reference to FIGS. FIG. 5 is a first embodiment of the hydrostatic bearing, and FIG. 6 is a second embodiment of the hydrostatic bearing.

In the embodiment shown in FIG. 5, the grindstone body 21 is provided with a ring-shaped spindle 22 and a grindstone 24 which is fitted into the inner peripheral portion of the spindle 22 and is non-detachably secured by a mounting plate 23. Inner teeth are formed on the inner peripheral surface of the. Further, the cross-sectional shape of the spindle 22 has a substantially rectangular outer surface.

On the other hand, a ring-shaped housing 25 is provided around the grindstone body 21 with a predetermined gap from the outer surface of the spindle 22.
Has a rectangular groove 25a into which a part of the rectangular end surface of the spindle 22 can be inserted.

The rectangular groove 25a is provided with an orifice hole 26 through which air can be blown toward the radial end surface of the spindle 22, and air is blown toward both side surfaces of the spindle 22 in the thrust direction. Opposite orifice holes 27, 27 facing each other are exposed, and compressed air is blown from these orifice holes 26, 27 so as to receive the bearing by static pressure.

Incidentally, in the case of the embodiment, a plurality of radial orifice holes 26 are arranged in two rows along the circumferential direction, and a plurality of thrust orifice holes 27 are also arranged facing each other. .

With this structure, the grindstone body 21 is also provided.
It is possible to reduce the rotational friction resistance of.

Next, FIG. 6 shows another embodiment in which bearings are subjected to static pressure. V is applied to the outer peripheral surface of the spindle 22 of the grindstone body 21.
A groove 25b is formed, and the corresponding housing 25 is formed.
An M-shaped groove 25b is formed on the inner peripheral surface of the. The same reference numerals are given to the same parts and the like as in the above example.

Within the M-shaped groove 25b of the housing 25, there are a pair of orifice holes 2 which are oblique to the radial direction and the thrust direction of the spindle 22, respectively.
Nos. 8 and 28 face each other, and air is blown from the orifice hole 28 so that both the radial direction and the thrust direction are simultaneously bearing.

In the case of this embodiment, the spindle 22
Dog teeth 29 for phase detection are provided on the side surface of
As shown in (b), the phase of the grindstone body 21 can be set to a predetermined phase by allowing the sensor 30 to face the dog teeth 29 in close proximity. Also, 31 in the figure
Is a spacer.

The rotary bearing portion having the above-described structure also has the same effect as described above, and the whetstone 21 can be rolled smoothly.

[0028]

As described above, according to the gear finishing apparatus of the present invention, the rotation speed is limited because the conventional large-diameter internal gear-shaped grindstone is rotated on the drive side. Since the gear to be processed having a small diameter is rotated on the drive side, the machining can be performed while rotating at high speed, and the machining capacity is improved. At this time, as the rotary bearing portion of the internal gear-shaped grindstone, the rotary friction resistance is reduced by three rotary rollers or static pressure bearings arranged at equal intervals on the outer circumference. The non-uniform frictional force does not act on the tooth surface, and the processing accuracy is maintained.

[Brief description of drawings]

FIG. 1 is a schematic plan view of the gear finishing device.

FIG. 2 is a side view of the same.

FIG. 3 is a sectional view of a main part

FIG. 4 is a sectional view taken along line AA of FIG.

FIG. 5 is a structural example diagram of a hydrostatic bearing.

FIG. 6 is a diagram showing another configuration example of the hydrostatic bearing.

[Explanation of symbols]

 6 Drive Motor 13, 21 Grindstone Body 16, 24 Grindstone 17 Rotating Roller 20a Groove 26, 27, 28 Orifice Hole W Gear to be Processed

Claims (3)

[Claims] 1. A honing process is performed by rotating an internal gear-shaped grindstone by engaging a gear to be processed with an internal-gear-shaped grindstone supported by a rotary bearing and rotating the processed gear by a driving means. In the gear finishing device described above, the rotary bearing portion is composed of three rotating rollers arranged at equal intervals along the outer circumference of the internal gear-shaped grindstone. 2. The gear finishing apparatus according to claim 1, wherein a groove portion corresponding to the outer peripheral surface shape of the internal gear toothed wheel is formed on the outer peripheral surface of the rotary roller. 3. A honing process is carried out by rotating a gear to be processed with an internal gear gear-shaped grindstone supported by a rotary bearing, and rotating the gear to be processed by a driving means. In the gear finishing device described above, the bearings in the radial direction and the thrust direction of the rotary bearing portion are constituted by static pressure bearings.