JP2000087993A - Cylindrical shaft, and spline part machining method of cylindrical shaft - Google Patents

Abstract

PROBLEM TO BE SOLVED: To connect spline parts to each other by correcting the phase deviation without intervention of a worker even with the phase of the spline parts deviated from each other in a connecting process to a projecting shaft. SOLUTION: In a cylindrical shaft 10 to which a projecting shaft 20 is spline- fitted, a tip part of a spline tooth of a female spline part 11 provided on its inner circumferential surface is formed tapered to the end. For example, when the phase of the spline parts 11, 21 of the shafts 10, 20 is deviated from each other in a process where the projecting shaft 20 is inserted in the cylindrical shaft 10 which is rotatably positioned and supported, the pressing force of, for example, the projecting shaft 20 is converted into the force to circumferentially rotate the cylindrical shaft 10 in the circumferential direction to correct the phase deviation between the spline parts 11, 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylindrical shaft used by being spline-fitted to a convex shaft, and to a method for processing a spline portion of the cylindrical shaft. This cylindrical shaft is, for example, a shaft end portion of a one-axis body constituting a telescopic shaft, a shaft end portion of a yoke of a universal joint, or one of a drive shaft of a tractor and an input shaft of various working machines towed by the tractor. It is provided at the shaft end.

[0002]

2. Description of the Related Art Generally, for example, when two shafts are connected via a universal joint, a yoke of the universal joint and each shaft may be spline-fitted. Is a cylindrical shaft having a female spline portion on the inner peripheral surface, and a shaft end portion of the shaft body is a convex shaft having a male spline formed on the outer peripheral surface.

[0003]

By the way, when inserting the convex shaft into the above-mentioned cylindrical shaft, if the shaft centers of both shafts are shifted or the spline portions of both shafts are shifted in phase, the inserted shaft is inserted. It becomes difficult.

Therefore, as a countermeasure for the former axial center misalignment, a tapered surface is provided at the open end of the cylindrical shaft, and a tapered surface is provided at the tip of the spline teeth of the convex shaft. The center action is used to make it easy to insert even if there is misalignment of the axis.

[0005] Regarding the latter countermeasure for phase shift, at present, an operator manually turns one axis by a required angle to adjust the phase and inserts the shaft. Was a trial and was troublesome.

Therefore, according to the present invention, even if the phases of the splines are shifted from each other in the connecting process with the convex shaft,
It is an object of the present invention to provide a cylinder shaft capable of correcting and connecting a phase shift without intervention of an operator and without performing repeated trials. Another object of the present invention is to provide a method of processing a spline portion of a cylinder shaft for easily obtaining a phase shift correction structure in the cylinder shaft.

[0007]

According to a first aspect of the present invention, there is provided a cylindrical shaft to which a convex shaft is spline-fitted, and a tip portion of a spline tooth of a female spline portion provided on an inner peripheral surface thereof. Are formed in a tapered shape.

A cylindrical shaft according to a second aspect of the present invention is a cylindrical shaft in which a convex shaft is spline-fitted, and has a tapered surface having an enlarged diameter at an open end of an inner peripheral surface thereof. The tip of the spline teeth of the female spline portion provided on the surface is formed in a tapered shape.

According to a third aspect of the present invention, in the cylindrical shaft according to the first or second aspect, a tip portion of the spline teeth is formed in a substantially semicircular shape in plan view.

According to a fourth aspect of the present invention, in the cylindrical shaft according to the first or second aspect, a tip portion of the spline teeth is formed substantially in a V shape in plan view.

According to a fifth aspect of the present invention, there is provided a method of machining a spline portion of a cylindrical shaft according to the third aspect, wherein the spline portion of the cylindrical shaft is machined using a rotary turning tool. Is formed in a cylindrical shape, and at least a concave portion which becomes conical during rotation is provided at the center of the distal end surface, and a notch having a substantially V-shaped cross-section in a radial direction from the distal end to a required length region in a required angular range of the outer periphery. Is prepared, the rotary turning tool is inclined with respect to the axis of the cylindrical shaft, and the inner surface of the recess is applied to the tip end of one spline tooth. The tip of the spline tooth is rounded by moving the spline tooth toward the back while rotating it.

According to a sixth aspect of the present invention, there is provided a method for machining a spline portion of a cylindrical shaft according to the fourth aspect, wherein the spline portion of the cylindrical shaft is machined using a rotary turning tool. Is formed in a cylindrical shape and has a shape that is reduced in diameter from the middle to the front end, and has a substantially L-shaped cut in a radial cross section in a required length region beyond the reduced diameter portion from the front end in a required angle range of the outer periphery. A tool provided with a notch is prepared, the rotary turning tool is set in an attitude along the axis of the cylindrical shaft, and the rotary turning tool is set in a state where its tip is applied to the tip of one spline groove. By moving the spline groove to the back while rotating, the corners at the tip side of the two spline teeth on both sides of the spline groove are simultaneously chamfered obliquely.

As described above, in the present invention, in short, the tip shape of the spline teeth of the cylindrical shaft is devised, so that even when the phases of the spline portions of both shafts are shifted from each other in the process of connection with the convex shaft, the shape of the spline teeth is not changed. Just match the cylinder axis,
Either shaft can be rotated in the circumferential direction. In other words, the splines of both shafts are out of phase,
When the convex spline teeth come into contact with the spline teeth of the cylindrical shaft by the butting operation of both shafts, the axial thrust of the convex shaft is dispersed by the tip shape of the spline teeth of the cylindrical shaft, Since either the convex shaft or the cylindrical shaft is rotated in the circumferential direction by the dispersed force, the phase shift of the spline portions of both shafts is corrected, and the spline portions are fitted to each other.

In addition, as a method for processing the spline teeth of the cylindrical shaft, a rotary turning tool is sequentially applied to each of the spline teeth or the spline grooves.
If the tip of the spline tooth is chamfered, the operation can be performed easily and quickly.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described based on embodiments shown in the drawings.

1 to 5 relate to a first embodiment of the present invention. FIG. 1 is a longitudinal side view of a cylinder shaft, FIG. 2 is a perspective view showing a cylinder shaft and a convex shaft, and FIG. FIG. 4 is a perspective view showing an example of a rotary turning tool used for machining a spline portion of a cylindrical shaft, and FIG. It is a vertical side view which shows the state which applied the turning tool.

In the drawing, reference numeral 10 denotes a cylindrical shaft, and reference numeral 20 denotes a convex shaft. The convex shaft 20 is connected to the cylindrical shaft 10 by spline fitting so as to be slidable in the axial direction and synchronously rotated in the circumferential direction. The cylindrical shaft 10 is formed in a cylindrical shape, and a female spline portion 11 is formed on an inner peripheral surface thereof. A diameter-enlarged tapered surface 12 is formed at one open end of the inner peripheral surface of the cylindrical shaft 10.

The convex shaft 20 is formed in a cylindrical shape, and a male spline portion 21 is formed on an outer peripheral surface thereof. A tapered surface 22 is formed at the tip of each spline tooth of the male spline portion 21 of the convex shaft 20.

The tip of each spline tooth of the female spline portion 11 of the cylindrical shaft 10 is round-chamfered so that the shape of the tip of the spline tooth becomes substantially semicircular in plan view. ing. This chamfered portion is called an arc surface 13. In addition, the enlarged diameter tapered surface 1 of the cylindrical shaft 10
2, a sector-shaped depression 14 is formed in a region of the female spline portion 11 on the tip side of each spline tooth.
As will be described later, the recessed portion 14 is formed by shaving when the arc surface 13 is formed on the spline teeth.

Next, a method for processing the female spline portion 11 of the above-described cylindrical shaft 10 will be described. Here, a rotary turning tool 30 having a cutting edge having a shape as shown in FIG. 4 is used. The rotary turning tool 30 has a decagonal outer shape, a conical concave portion 31 provided at the center of the distal end surface thereof, and a diameter from the distal end to a required length region in a required angular range of 180 degrees facing the outer periphery. Substantially V-shaped notches 32, 33 are provided in the cross section in the direction.

Here, as shown in FIG. 5, the rotary turning tool 30 is inclined with respect to the axis of the cylindrical shaft 10 and the inner surface of the recess 31 is formed at the tip of one spline tooth of the female spline portion 11. , The rotary turning tool 30 is moved to the back while rotating. As a result, both corners of the tip end portion of the spline teeth are rounded and the arc surface 13 is formed. The use of such a rotary turning tool 30 results in the formation of a sector-shaped depression 14 with respect to the enlarged taper surface 12 of the cylindrical shaft 10, but the depression 14 has a shape that extends along the axial direction. , So that it does not hinder the connection with the convex shaft 20. The inclination angle of the rotary turning tool 30 may be set arbitrarily, but is preferably set to be equal to the inclination angle of the concave portion 31 of the rotary turning tool 30.

In the case of the cylindrical shaft 10 described above, in the connecting process with the convex shaft 20, the axes of the shafts 10 and 20 are shifted or the spline portions 11 and 21 of the shafts 10 and 20 are connected. Even if the phase is shifted, the center shift and phase shift are performed without manual intervention as described below,
Also, the correction is automatically made without the need for repeated trials.

That is, if the axes of the shafts 10 and 20 are shifted from each other, the operation of abutting the shafts 10 and 20 causes the tapered surface 12 of the cylindrical shaft 10 and the spline teeth of the convex shaft 2 to move. Abuts against the tapered surface 22 of the convex shaft 2.
The tapered surface 12 of the cylindrical shaft 10 with the axial thrust of 0
The convex shaft 20 is displaced in the radial direction along the axis, so that the axis of the cylindrical shaft 10 and the axis of the convex shaft 20 match.

If the phases of the spline portions 11 and 21 of the two shafts 10 and 20 are shifted from each other in the above-described connection process,
Arc surface 13 of each tooth tip of female spline portion 11 of cylindrical shaft 10
In the meantime, the tooth tip of the male spline portion 21 of the convex shaft 20 comes into contact, but the arc surface 13 acts so as to convert the axial propulsive force of the convex shaft 20 into a rotational force in one circumferential direction. Therefore, the convex shaft 20 is rotated by the required angle, and the phase of the male spline portion 21 is changed to the female spline portion 1.
1 will be matched. The rotation of the convex shaft 20 in this phase correction operation becomes smooth because the spline teeth of the male spline portion 21 are guided while sliding along the arc surface 13 of the female spline portion 11.

As described above, in the process of connecting the cylindrical shaft 10 and the convex shaft 20, in particular, the spline portions 1 of the two shafts 10, 20 are formed.
Even if the phases are shifted from each other, there is no need for the operator's hand as in the related art, and the connecting operation can be easily performed.

6 to 10 relate to a second embodiment of the present invention. FIG. 6 is a longitudinal side view of a cylinder shaft, FIG. 7 is a perspective view showing a cylinder shaft and a convex shaft, and FIG. FIG. 9 is an explanatory diagram showing a phase shift correction mode in a process of connecting a cylindrical shaft and a convex shaft. FIG. 9 is a perspective view showing an example of a rotary turning tool used for processing a spline portion of a cylindrical shaft.
FIG. 10 is a longitudinal sectional side view showing a state in which a rotary turning tool is applied to a cylinder axis.

In the second embodiment, obliquely curved slopes 13 'are formed on both sides in the circumferential direction of the distal end portions of the spline teeth of the female spline portion 11 of the cylindrical shaft 10, so that the distal end portions of the spline teeth are formed. The shape is almost V in plan view
It is shaped like a letter. In addition, on the above-mentioned slope 13 ',
Two slopes 13 'located on the spline groove side are paired, and have a shape of a mortar.

Further, the region on the tip end side of each spline groove of the female spline portion 11 on the diameter-increased tapered surface 12 of the cylindrical shaft 10 is connected to the pair of two inclined surfaces 13 'located on the above-described spline groove side. A fan-shaped depression 14 'is formed.

It should be noted that a pair of two slopes 13 'and a depression 14' formed at the tip of the above-described spline groove are formed.
It serves as a guide surface for correcting a phase shift when the convex shafts 20 are connected.

A method of processing the female spline portion 11 of the cylindrical shaft 10 will be described. Here, a rotary turning tool 40 having a cutting edge having a shape as shown in FIG. 9 is used. The rotary turning tool 40 has an outer shape formed in a decagonal shape, a shape whose diameter is reduced from the middle to the front end, and an outer periphery 18.
Notches 42 and 43 having a substantially L-shaped cross section in the radial direction are provided in a required length region beyond the reduced diameter portion 41 from the tip in a required angle range opposing 0 °.

Here, as shown in FIG. 10, the rotary turning tool 40 is set in an attitude along the axis of the cylindrical shaft 10, and the tip of the rotary turning tool 40 is applied to the tip of one spline groove. The turning tool 40 is moved backward while rotating. As a result, two splines on both sides of the spline groove are formed.
One of the front end side corner of the spline teeth is to be chamfered in a curved shape obliquely simultaneously, resulting in two pair of inclined surfaces 13 'and recess 14' guiding surface consisting of a the distal end portion of the spline grooves Will be formed. Thereafter, the above-described processing is performed on all spline teeth. As a result, the above-described guide surface is formed at the tip of each spline groove, and the shape of the tip of each spline tooth is substantially V-shaped in plan view.

Since the above-mentioned recessed portion 14 'is formed along the axial direction and is set to have a predetermined diameter, it does not hinder the connection of the convex shaft 20. Since the thickness of the opening 10 is not made thinner than necessary, the outer diameter of the cylindrical shaft 10 does not need to be increased.

In the second embodiment, similarly to the first embodiment, even if a misalignment or a phase shift occurs in the process of connecting the cylindrical shaft 10 and the convex shaft 20, it is automatically and smoothly corrected. be able to.

The cylindrical shaft 10 of the first and second embodiments can be used by being attached to the shaft end of a yoke 1 for a cross joint, for example, as shown in FIG. In addition,
As shown in FIG. 12, the cylindrical shaft 10 may be formed integrally with the shaft end portion of the yoke 1 for the cross joint.

In addition, the cylinder shaft 1 of the first and second embodiments described above.
0 is the drive shaft 2 of the tractor 2 as shown in FIG.
It can be used as a coupling for connecting the convex input shaft 3a of the working machine 3 to a. In FIG. 13, a configuration utilizing the cylindrical shaft 10 of the first embodiment is used. Specifically, one yoke 2c of a cross joint 2b attached to the free end of the drive shaft 2a of the tractor 2
The cylindrical shaft 10 is integrally provided at the shaft end in the form as shown in FIG.

In the example shown in FIG. 13, the drive shaft 2a of the tractor 2 and the input shaft 3a of the work machine 3 are arranged on the tractor 2 side so that they can be automatically connected without manual intervention. Arm unit A that is installed and draws work machine 3
A locking unit B disposed on the work machine 3 side and locked by the arm unit A; and an arm unit A of the tractor 2
And a support unit C for supporting the one yoke 2c of the cross joint 2b in such a manner that the one yoke 2c is rotatable in a substantially horizontal posture and is tiltable and radially displaceable. As shown in FIG. 14, for example, the support unit C includes an annular frame 4 fixed to the arm unit A of the tractor 2, a self-aligning ball bearing 5 attached to the annular frame 4, and a self-aligning ball. The bearing 5 includes three coil springs 6 that suspend and hold the bearing 5 substantially at the center of the annular frame 4. Annular frame 4
Are a pair of annular plates 4a and 4b, and annular plates 4a and 4b.
And an inner cylinder 4c and an outer cylinder 4d disposed radially inwardly and outwardly. The inner cylinder 4c is slidable in the radial direction. A coil spring 6 is provided at three places around the outer cylinder 4d.
Three hollow bolts 4e for adjusting the amount of compression are screwed.

If the cylinder shaft 10 of the present invention is used as such a coupling for connecting the tractor 2 and the working machine 3, the phase shift correction function of the cylinder shaft 10 of the present invention becomes extremely effective, and 2 can be greatly contributed to further smooth connection operation between the drive shaft 2a and the input shaft 3a of the work machine 3.

Further, in the tractor 2 as described above, there is a case where the support unit C for horizontally supporting the drive shaft 2a is not used. In such a case, FIG.
5, the open end of the safety boot 7 surrounding the cross joint 2b receives the one yoke 2c of the cross joint 2b so as to manage the hanging angle θ of the one yoke 2c of the cross joint 2b. Is preferred. In that case, cross joint 2
The axial dimension L of the safety boot 7 and the diameter R of the open end of the safety boot 7 are set in accordance with the required value of the hanging angle θ of the one yoke 2c.

The shapes of the rotary turning tools 30 and 40 in the first and second embodiments are not particularly limited. For example, each of the rotary turning tools 30 and 40 can have a shape having only the upper half. This is because the outer diameter of the rotary turning tools 30, 40 becomes circular due to the rotation operation.

In addition, the cylinder shaft 10 shown in the second embodiment
For processing of the female spline portion 11, for example, a modified end mill, drill, or the like, which is generally known, can be used. Specifically, as shown in FIGS. 16 to 18, a rotary turning tool 50 having a two-flute end mill as a base and a tip of which is reduced in diameter can be used.

With respect to the rotary turning tool 50, the diameter R of the rotary arc trajectory of the blade, the axial length W of the reduced diameter portion 51, and the inclination angle θ of the reduced diameter portion 51 are as follows. Must be specified in

First, as shown in FIG. 19, as for the diameter R of the rotating arc locus, as shown in FIG. 19, a guide surface (a pair of two inclined surfaces 13 'and a recessed portion 14') formed at the tip of each spline groove of the cylindrical shaft 10 is formed. ) Is set to be the same as the diameter r of the virtual arc X passing through the three points P1, P2, and P3. As shown in FIG. 20, the axial length W of the reduced diameter portion 51 is set to be equal to or larger than the axial length L of the slope 13 '. Further, the inclination angle θ of the reduced diameter portion 51 is set to be the same as the angle α of the V-shaped tip of the spline teeth.

[0043]

In the cylindrical shaft according to the first to fourth aspects of the present invention, even if the phases of the spline portions of both shafts are shifted at the time of connection with the convex shaft, the two shafts can be manually engaged only by abutting these shafts. In addition, the phase shift can be automatically corrected without repeating the trial, and the connecting operation can be easily and smoothly performed.

In particular, according to the second aspect of the present invention, in addition to the above-mentioned effects, even when the splines of both shafts are misaligned in the connecting process with the convex shaft, the convex shaft and the cylindrical shaft are abutted. In this way, it is possible to easily and smoothly perform the connecting operation by correcting the shaft center deviation without manual operation.

According to a fifth aspect of the present invention, there is provided a machining method of the spline teeth of the cylindrical shaft according to the third aspect of the present invention. Therefore, the machining of the spline teeth of the cylindrical shaft can be performed easily and quickly, thereby contributing to an improvement in productivity.

[Brief description of the drawings]

FIG. 1 is a longitudinal side view of a cylinder shaft according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a cylindrical shaft of Embodiment 1 and a convex shaft of a connecting partner thereof.

FIG. 3 is an explanatory diagram showing a phase shift correction mode in a connecting process between a cylindrical shaft and a convex shaft according to the first embodiment;

FIG. 4 is a perspective view showing a rotary turning tool used for processing a spline portion of a cylindrical shaft according to the first embodiment.

FIG. 5 is a longitudinal sectional side view showing a state in which a rotary turning tool is applied to the cylinder shaft of the first embodiment.

FIG. 6 is a longitudinal sectional side view of a cylinder shaft according to a second embodiment of the present invention.

FIG. 7 is a perspective view showing a cylindrical shaft according to a second embodiment and a convex shaft of a connecting partner thereof.

FIG. 8 is an explanatory diagram showing a phase shift correction mode in a connecting process between a cylindrical shaft and a convex shaft according to a second embodiment.

FIG. 9 is a perspective view showing a rotary turning tool used for processing a spline portion of a cylindrical shaft according to a second embodiment.

FIG. 10 is a longitudinal sectional side view showing a state in which a rotary turning tool is applied to a cylindrical shaft according to a second embodiment.

FIG. 11 is a longitudinal sectional side view showing a cross joint to which the cylindrical shaft according to the first embodiment is attached.

FIG. 12 is a longitudinal sectional side view showing a cross joint in which a cylindrical shaft of Embodiment 1 is integrally formed.

FIG. 13 is a side view showing an example in which the cylinder shaft according to the first embodiment is used as a coupling for connecting a tractor and a working machine.

FIG. 14 is a longitudinal sectional side view showing the support unit in FIG. 13;

15 is a vertical sectional side view of the upper half showing a case where the support unit is not provided with the drive shaft in FIG. 13;

FIG. 16 is a perspective view showing another rotary turning tool used for machining the cylindrical shaft according to the second embodiment.

FIG. 17 is a side view of the rotary turning tool of FIG. 16;

FIG. 18 is an end view of the rotary turning tool of FIG. 16;

FIG. 19 is an explanatory view showing one element of a design condition of the rotary turning tool in the case where the cylindrical shaft according to the second embodiment is machined by the rotary turning tool of FIG. 16;

FIG. 20 is an explanatory view showing other elements of the design conditions of the rotary turning tool when the cylindrical shaft of the second embodiment is machined by the rotary turning tool of FIG. 16;

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 cylindrical shaft 11 female spline portion of cylindrical shaft 12 enlarged taper surface of cylindrical shaft 13 arc surface of spline teeth of cylindrical shaft 20 convex shaft 21 male spline portion of convex shaft

Claims (6)

[Claims] 1. A cylindrical shaft to which a convex shaft is spline-fitted, wherein a tip portion of a spline tooth of a female spline portion provided on an inner peripheral surface thereof is formed in a tapered shape. Tube shaft. 2. A cylindrical shaft to which a convex shaft is spline-fitted, wherein a tapered surface having an enlarged diameter is formed at an open end of an inner peripheral surface thereof, and a spline of a female spline portion provided on the inner peripheral surface. A cylindrical shaft, wherein a tip portion of a tooth is formed in a tapered shape. 3. The cylinder shaft according to claim 1, wherein a tip portion of the spline teeth is formed in a substantially semicircular shape in plan view. 4. The cylinder shaft according to claim 1, wherein a tip portion of the spline teeth is formed substantially in a V-shape in plan view. 5. The method of processing a spline portion of a cylindrical shaft according to claim 3, using a rotary turning tool, wherein the rotary turning tool has an outer shape formed in a cylindrical shape and has at least a center at a center of a front end surface. A rotary turning tool is provided which is provided with a concave portion which becomes conical during rotation and which is provided with a substantially V-shaped notch in a radial cross section in a required length region from a tip in a required angle range of the outer periphery. In a state of being inclined with respect to the axis of the cylindrical shaft, and moving the rotary turning tool to the back while rotating the rotary turning tool in a state where the inner surface of the concave portion is applied to the tip of one spline tooth, thereby obtaining the spline. A method of machining a spline portion of a cylindrical shaft, wherein a tip portion of a tooth is rounded. 6. A method for processing a spline portion of a cylindrical shaft using a rotary turning tool according to claim 4, wherein the rotary turning tool has an outer shape formed in a cylindrical shape and from the middle to the tip. A notch having a substantially L-shaped notch in a radial cross section is provided in a required length region beyond the reduced diameter portion from the tip in a required angle range of the outer periphery. By rotating the rotary turning tool to the back while rotating the rotary turning tool while the tool is in a posture along the axis of the cylindrical shaft and the tip end portion is applied to the tip end portion of one spline groove, the spline groove is moved. The method for machining a spline portion of a cylindrical shaft, comprising simultaneously chamfering the corners on one side of the tip of two adjacent spline teeth.