JP3415423B2 - Shaft coupling shaft fastening device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure in which a flange portion and a boss portion of a shaft coupling used for high precision and positioning of a control motor in machine tools, robots, OA equipment and the like are reduced in diameter and fastened to a shaft. The present invention relates to a shaft fastening device for a shaft coupling.

[0002]

2. Description of the Related Art Conventionally, in a shaft fastening device for a shaft coupling of this type, as shown in FIGS.
A taper boss portion 101 is integrally formed with the taper boss portion 101, a radial cut groove 102 is formed only on one side of the taper boss portion 101, and a tightening ring 103 having an inner surface fitted to the boss portion 101 is formed into a tapered shape, Screw hole on flange 10
4 is provided and is tightened with a bolt 106 through a through hole 105 of a tightening ring 103 is known.

[0003]

The above-mentioned conventional shaft coupling is
When bolts are tightened to tighten the boss with a ring, the internal diameter of the boss is reduced and internal stress is applied to the center of the flange, and the flange is pulled into the boss by tightening the bolt. Then, the center of the flange portion bulged and deformed toward the boss portion side like an umbrella, and the flatness of the flange portion was greatly changed. That is, the deformation amount due to the diameter reduction and the deformation amount due to the force of pulling the flange due to the bolt fastening work synergistically to generate the deformation of several tens of microns or more. Therefore, if this flange surface undergoes such a large deformation, there is a problem that wear of the metal supporting the cross pin of the intermediate body connected between the flanges, abnormal expansion of the leaf spring between the flange and the spacer, loosening, etc. occur. However, the life of the shaft coupling was short, and it was unsuitable for use in machine tools, robots, office automation equipment, etc. that require high accuracy and positioning.

In order to solve the above-mentioned conventional problems, the present inventor has found that the radial reduction groove formed on the boss portion, the axial reduction concave groove on both inner circumferences, and the flange portion. The boss part can be evenly fastened to the shaft by the combination of the flexible connecting part formed on both sides with the arc groove of the connecting part of the boss part, and the flange surface is deformed by stress regardless of whether the fastening means is fastened or removed. It is an object of the present invention to provide a highly accurate shaft coupling device for a shaft coupling, which does not adversely affect the cross pin of the intermediate body of the shaft coupling and its metal, leaf spring and the like.

[0005]

According to a first aspect of the present invention, there is provided a shaft fastening device for a shaft coupling, wherein a taper boss portion integrally formed with a flange portion is formed with a radially reducing groove for reducing the diameter, and the flange portion is formed. A groove for reducing the diameter is formed on the inner peripheral surface of the inner peripheral surface of the inner peripheral surface of the flange portion and the boss portion continuously to the inner end, and the inner end is formed on both sides of the inner peripheral surface of the flange portion and the boss in a direction orthogonal to the axis of the diameter reducing groove. A groove for reducing the diameter is formed in the axial direction from the end to the outer end, and circular arc grooves are bored in the radial direction above and below the peripheral surface of the joint portion of the flange portion and the boss portion to form flexible connecting portions on both sides. Further, a taper cap is provided on the boss portion so that the taper cap can be fastened by a fastening means, and when the taper cap is fitted and fastened to the boss portion, each part of the boss portion can be uniformly reduced in diameter with respect to the shaft and fastened. It is a thing.

According to the configuration of the first aspect of the invention described above, the diameter reducing groove formed in the upper and lower radial directions of the flange portion and the tapered boss portion, the diameter reducing concave groove continuous with the diameter reducing groove, and the flange portion. And a groove for reducing the diameter that is formed in the axial direction from the inner end to the outer end on both sides of the inner circumference of the boss, and an arc groove is formed on the circumferential surface of the joint between the flange and the boss. By combining with the flexible connecting part, when the taper cap is fitted and fastened to the boss part, the stress for narrowing the diameter reduction groove of the boss part and the subsequent groove for diameter reduction of the flange part acts, and the flange Since the upper and lower circular arc grooves are provided in the connecting portion between the boss portion and the boss portion, a stress that reduces the diameter toward the center is applied to the flexible connecting portions on both sides of the flange portion and the boss portion. It can be reduced in diameter and fastened to the shaft. Thus, the influence of the internal stress due to the diameter reduction of the boss on the flange is extremely small, the flange surface does not deform regardless of the time of fastening or removal, and the cross pin of the intermediate body of the shaft coupling and its metal, Make sure that there is no adverse effect on the leaf springs, etc., and that metal wear, abnormal extension of the leaf springs, and loosening do not occur.

According to a second aspect of the invention, as the fastening means,
It is characterized in that a screw hole is provided on the end surface of the tapered boss portion, an insertion hole is provided in a taper cap having a shaft hole at the center, and a bolt can be fastened to the screw hole through the insertion hole.

According to the second aspect of the invention, the taper cap is fitted into the tapered boss portion, and the bolt is fastened to the screw hole of the boss portion through the insertion hole of the cap. Since it can be reduced in diameter as described above and it is not directly tightened with the flange, it does not pull the flange surface, and each part of the boss can be equally tightened as described above, and the flange surface is not deformed. We can provide high precision shaft couplings, machine tools, robots, OA
It is suitable for use in high precision and positioning of control motors in equipment.

[0009]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a front view of a shaft coupling of the present invention, and FIG.
3 is a vertical sectional view of the same portion, FIG. 4 is a sectional view taken along line YY of FIG. 3, FIG. 5 is a sectional view taken along line XX of FIG. 1, and FIG. 6 is a boss of the same flange. 7 is a side view of another embodiment, FIG. 8 is a longitudinal sectional view of the same, and FIG. 9 is a view showing the boss portion and the cap portion of the same flange separately. It is a partially broken perspective view.

The shaft couplings shown in FIGS. 1 to 6 show the case where the elliptical flange portion integrally formed with the boss portions provided on both sides of the intermediate cross joint pin has one side orthogonal to the other side. That is, the cross joint pin has a support pin in the cross direction, has a through hole at the center through which the rotary shaft can be inserted, and slides the cross joint pin on the bearing on the facing surface of the hub with the bearing arm provided on the cross. The shaft is rotatably supported and absorbs the eccentric declination that occurs between the rotating shafts to transmit between the two shafts.

1 to 6, the hub of the shaft coupling is composed of an elliptical flange portion 1 and a tapered boss portion 2 having a tapered outer peripheral surface. Reference numeral 3 denotes an intermediate cross joint pin, which is axially supported by bearing portions 4 provided above and below the flange portion. Reference numeral 5 is a metal taper cap having an inner circumference fitted to the tapered surface of the boss portion 2 as a tapered surface. A rotating shaft 6 is inserted into the shaft holes of the taper cap, the boss portion and the flange portion and fastened by fastening means.

The tapered boss portion 2 is provided with a shaft hole 11 up to the flange portion 1, and the outer peripheral surface thereof is a tapered surface 12,
A diameter-reducing groove 13 is formed on the upper and lower sides of the flange 1 so as to be radially separated from the outer periphery to the shaft hole, and the diameter-reducing groove 13a is formed continuously on the inner peripheral surface of the flange portion 1 to the inner end. To form. The cutting depth of the diameter-reducing groove 13a is equal to the diameter-reducing groove 13a.
Is formed to be slightly deeper than the wall thickness of the boss. The depth of cut may be approximately the same as the thickness of the boss portion. Thus, the diameter reducing groove 13 is separated from the tip of the boss portion to the flange surface, but the diameter reducing groove 13a formed continuously is the inner diameter surface of the flange portion 1. Is formed by cutting, and when tightening the boss portion 2 with the cap 5,
The shaft can be tightened from the tip side of the boss to the inner end of the flange. Strictly speaking, at the time of tightening, the tip of the separated boss is narrowed by the tightening force due to the clamping pressure of the taper surface, and the flange diameter reducing groove 13a side is slightly tightened, but the thickness of the flange is small. Deformation is suppressed at the flesh portion, a slight internal stress acts, and the flange surface is hardly deformed.

On both sides of the inner peripheral surface of the flange portion 1 and the boss portion 2, a diameter reducing groove 14 is formed in the axial direction from the inner end to the outer end in a direction orthogonal to the axis of the diameter reducing groove 13. That is, the diameter-reducing groove 14 provided in the axial direction from the inner end to the outer end has a depth of about half the wall thickness of the boss portion and leaves a linear elastic thin portion 15 on the outer periphery. It is preferable that the thickness of the elastic thin portion 15 be such that rigidity other than torsional rigidity can be minimized. When the boss 2 is tightened with the cap 5, the taper surface presses the diameter-reducing groove 13 of the boss, and the elastic thin-walled portion is subjected to bending stress to reduce the diameter from the tip side of the boss to the inner end of the flange. The shaft can be evenly tightened. Strictly speaking, at the time of this tightening, bending stress is applied to the tip of the boss portion to narrow the diameter-reducing groove, and the flange-side groove is prevented from being deformed by the thick part of the flange portion, and only a small internal stress is applied. The flange surface is hardly deformed. The recessed groove 14 for reducing the diameter is shown as being provided in the center of both sides of the inner peripheral surface of the flange portion and the boss portion, but the present invention is not limited to this, and there is a plurality of symmetrical portions within the width of the flexible connecting portion. May be provided.

Also, the connecting portion 1 of the flange portion 1 and the boss portion 2
Circular arc grooves 17 are bored in the upper and lower sides of the peripheral surface of 6 to form radial flexible connecting portions 18 having a predetermined width on both sides of the connecting portion 16. The width L of the flexible connecting portion 18 is such that the flange surface is not deformed, and the flexible connecting portion 18 has optimum flexibility and rigidity capable of uniformly reducing the diameter when the boss portion is tightened. In the embodiment, as shown in FIG. 4, the arc groove 17 is formed such that the bottom of the groove is straight and the upper and lower surfaces of the connecting portion 18 are linearly formed. However, the invention is not limited to this, and the arc groove is not limited to this. Optimal flexibility for connecting parts,
It may be formed by cutting it into a fan shape with a predetermined angle around the axis so as to have rigidity. When tightening the boss portion 2 with the cap 5, the bending force in the central direction acts on the flexible connecting portion 18 due to the clamping force of the tapered surface, but the flexible connecting portion 18 can absorb the bending stress in the connecting portion, and the area to be joined with the flange surface. Therefore, the bending stress has almost no effect on the flange surface. Screw holes 19 into which the bolts 23 are screwed are provided on both sides of the end surface of the boss portion 2. Since the diameter-reducing groove 14 is located toward the center of the flexible connecting portion 18, when the diameter-reducing groove 14 is narrowed when the boss portion is tightened with the cap, the elastic thin portion 15 thereof is formed. The stress applied to the flexible connecting portion 18
It will take the most near the center of. However, the stress when the boss portion is tightened can be absorbed by narrowing the diameter reducing groove 14 from the tip of the boss portion to the flange portion, and a slight stress is applied near the center of the flexible connecting portion 18, Since the flexible connecting portion 18 is arcuate and has a certain width, it is not deformed.

The taper cap 5 comprises a cylindrical portion 5a having substantially the same length as the boss portion 2 and an annular front surface portion 5b having a shaft hole 20 at the center thereof, and the inner peripheral surface of the cylindrical portion 5a is tapered. A tapered surface 21 that fits into the boss portion is formed, and insertion holes 22 through which the bolts 23 are inserted are formed on both sides of the front surface portion.

In another embodiment shown in FIGS. 7 to 9, a leaf spring and a spacer are placed between hubs, a flange portion and a leaf spring are opposed to each other at a plurality of positions, and the hubs are connected by tightening and fixing them with tightening bolts. The shaft coupling which transmits between two shafts is shown.

In this embodiment, the hub of the shaft coupling is composed of an elliptical flange portion 1 and a tapered boss portion 2 having a tapered outer peripheral surface. Reference numeral 7 is an intermediate spacer, 8 is a leaf spring, and the leaf spring 8 is interposed between the flange 1 and the spacer, and the leaf spring 8 is fixed to the upper and lower sides of the flange portion 1 with a tightening bolt 9. The flange portion 1 and the boss portion 2 have a diameter reducing groove 13, a diameter reducing concave groove 13a, and
The diameter-reducing concave groove 15 and the circular arc groove 17 are formed, and the flexible connecting portion 1 is formed.
8 is formed.

According to the structure of the present invention described above, when the boss portion 2 is tightened by the cap 5, the taper surface is pressed to tighten the shaft from the tip end side of the boss portion to the inner end of the flange portion to reduce the diameter. A diameter reduction by pinching the diameter reduction groove 13a and a diameter reduction groove 14 from the tip side of the boss portion to the inner end of the flange portion due to the bending stress of the elastic thin portion 15,
The deformation is dispersed and absorbed by the flexible connecting portion 18 by the action of the arcuate groove 17 at the connecting portion of the flange portion and the boss portion, and the deformation on the flange surface can be made extremely small, about several microns. Therefore, when the shaft is fastened or unfastened, the taper boss and flange can be reduced in diameter by reducing the deformation of the flange due to the hub and shaft fastening with a simple operation of tightening the taper cap with the tightening bolt. The recessed groove and arc groove make the diameter of each part of the boss part uniform to minimize deformation and surface wobbling of the flange surface, and adversely affect the cross pin of the intermediate body connected to the flange surface and its metal, leaf spring, etc. There can be no.

Although the embodiment has been described above, the present invention is not limited to this embodiment, and various embodiments can be implemented without departing from the gist of the present invention.

[0020]

According to the present invention, the diameter-reducing groove formed in the upper and lower radial directions of the flange portion and the tapered boss portion, the diameter-reducing groove continuous with the diameter-reducing groove, the flange portion and the boss portion. Between the inner end and the outer end on both sides of the inner periphery of the groove for diameter reduction formed in the axial direction, and the flexible connecting portion on both sides by the arcuate groove formed on the peripheral surface of the joint portion of the flange portion and the boss portion. Depending on the combination, when the taper cap is fitted and fastened to the boss portion, the stress for narrowing the diameter reducing groove of the boss portion and the subsequent groove for reducing the diameter of the flange portion acts, and the flange portion and the boss portion are combined. Since the connecting portion is provided with the arcuate groove, the flexible portions existing on both sides of the flange portion and the boss portion are subjected to the stress of reducing the diameter toward the center, so that the boss portion can be uniformly reduced in diameter and fastened to the shaft. Therefore, the influence of internal stress due to the diameter reduction of the boss on the flange is extremely small, and there is little deformation or surface wobbling on the front surface of the flange surface at the time of fastening or removal, and high fastening force and high rigidity shaft fastening force. Since the shaft joint using the bearing does not deform the flange surface, there is no metal wear, and the leaf spring type shaft joint does not cause abnormal expansion or loosening of the leaf spring. Life expectancy can be expected. Therefore, it is suitable for use in machine tools, robots, office automation equipment, etc. for high precision and positioning of control motors.

Further, since the taper cap is fastened to the end surface of the tapered boss portion with a bolt, the boss portion can be formed by simply fitting the cap on the boss portion and tightening the bolt through the insertion hole of the cap into the screw hole of the boss portion. Since the diameter can be reduced and the flange is not directly tightened, the flange surface is not pulled and each part of the boss can be evenly tightened as described above, and the flange surface is not deformed. The shaft coupling can be provided.

[Brief description of drawings]

FIG. 1 is a front view of a shaft coupling of the present invention.

FIG. 2 is a cutaway side view of the same portion.

FIG. 3 is a vertical sectional view of the same.

4 is a cross-sectional view taken along the line YY of FIG.

5 is a cross-sectional view taken along line XX of FIG.

FIG. 6 is a partially cutaway perspective view showing a boss portion and a cap portion of the flange separately.

FIG. 7 is a side view of another embodiment.

FIG. 8 is a vertical sectional view of the same.

FIG. 9 is a partially cutaway perspective view showing a boss portion and a cap portion of the flange separately.

FIG. 10 is a side view of a conventional shaft coupling.

FIG. 11 is a vertical sectional view of the same.

FIG. 12 is a partially cutaway perspective view showing a boss portion and a cap portion of the flange separately.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Flange part, 2 ... taper boss part, 5 ... taper cap, 13 ... diameter-reduction groove, 13a ... diameter-reduction groove, 14 ...
Recessed groove for reducing diameter, 17 ... Arc groove, 18 ... Flexible connecting portion, 19
... screw holes, 22 ... insertion holes, 23 ... bolts.

Front page continuation (58) Fields surveyed (Int.Cl. ⁷ , DB name) F16D 1/00-1/08 F16D 3/26

Claims (2)

(57) [Claims] 1. A taper boss portion integrally formed with a flange portion is formed with a radially reducing groove that is separated in the radial direction, and the inner peripheral surface of the flange portion is continuous with the diameter reducing groove to the inner end. Forming a groove for reducing the diameter, and forming a groove for reducing the diameter in the axial direction from the inner end to the outer end in a direction orthogonal to the axis of the diameter reducing groove on both inner peripheral surfaces of the flange portion and the boss, and Arc-shaped grooves are formed in the upper and lower peripheral surfaces of the connecting portion of the flange portion and the boss portion in the radial direction to form flexible connecting portions on both sides, and a taper cap is provided on the boss portion so as to be fastened by fastening means, A shaft fastening device for a shaft coupling, characterized in that when the taper cap is fitted and fastened to the boss portion, each portion of the boss portion can be uniformly reduced in diameter and fastened to the shaft. 2. As the fastening means, a screw hole is provided in an end surface of a tapered boss portion, an insertion hole is provided in a taper cap having a shaft hole at the center, and a bolt can be fastened to the screw hole through the insertion hole. A shaft fastening device for the described shaft coupling.