JP2000210857A - Groove grinding method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the degree of freedom in the grinding work of a groove by displacing a grinding roller along an inner wall surface of a work from an upper side to a lower side of an opening under the turning operation of the grinding roller having a pin member as a turning shaft. SOLUTION: A robot is controlled under the turning operation of a grinding roller 30, and the grinding roller 30 is displaced along the three-axial directions of XYZ so as to abut on an inner wall surface of a cup part 66 of an outer cup. The robot is controlled to reciprocate the grinding roller 30 along the inner wall surface of the outer cup between the upper part and the lower part while keeping the turn of the grinding roller about a pin member 28 at a predetermined rotating speed to grind a track groove by the grinding roller 30. On this occasion, the grinding roller 30 may be reciprocated from the upper part toward the lower part of the inner wall surface of the cup part 66 in the outer cup, or reciprocated from the lower part toward the upper part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for grinding a groove portion capable of grinding a track groove or the like provided on an inner wall surface of an outer cup of a constant velocity joint.

[0002]

2. Description of the Related Art Conventionally, automobiles have used a constant velocity joint as a mechanism for transmitting the rotational driving force of an engine to wheels. For example, a bar-field type constant velocity joint includes an outer cup having a plurality of track grooves formed on an inner wall surface, and an inner member housed in the outer cup.

[0003] The inner member includes a plurality of balls rolling along the track groove, an inner race having a groove for rolling the ball, and a retainer for rotatably holding the ball. including.

The track groove of the outer cup and the groove portion of the inner race are formed by, for example, performing plastic working by forging, and then performing grinding (polishing) using a grinding wheel.

FIG. 11 shows a conventional grinding machine for forming a track groove by grinding an inner wall surface of an outer cup which is a work (for example, see Japanese Patent Application Laid-Open No. Hei 5-1).
No. 31372).

The grinding machine 1 has a slide table 4 slidably provided in a direction indicated by an arrow A along a pair of rails 3 laid on the upper surface of a frame 2.
Is provided with an inclined grinding unit 5 slidable in the direction of arrow B. The grinding unit 5 has a main shaft 7 protruding toward a work 6, and a grinding wheel 8 is fixed to a tip of the main shaft 7. The tip of the grinding wheel 8 is formed in a hemispherical bell shape, and is rotatably provided about the axis of the main shaft 7 as a rotation center under the rotational driving action of a motor (not shown).

The work 6 is provided so as to reciprocate in the direction of arrow C (see FIG. 12) by a tilt mechanism (not shown) that tilts the work support 10 about the shaft 9 by a predetermined angle.

Accordingly, in the grinding machine 1 according to the prior art, the slide table 4 and the grinding unit 5 are displaced through a displacing means (not shown) to the state shown in FIG. Grinding wheel 8 is arrow C
The track groove 11 is formed by grinding the inner wall surface of the work 6 that tilts along the direction (see FIG. 13).

[0009]

However, in the grinding machine 1 according to the prior art, it is necessary to tilt the work 6 by a predetermined angle in order to form the track groove 11 along the inner wall surface of the outer cup. There is an inconvenience that the configuration of the grinding machine 1 becomes complicated and the cost required for capital investment increases.

[0010] In the grinding machine 1 according to the prior art,
Since the track groove 11 is ground under the rotating action of the grinding wheel 8, the cross section of the track groove 11 can be ground into an arc shape or a substantially semicircular shape having a radius R (FIG. 13). For example, there is a disadvantage that a track groove having a rectangular cross section such as a V groove cannot be formed.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-mentioned inconveniences. The present invention has been made by reducing the manufacturing cost by simplifying the entire apparatus and by forming track grooves having various cross-sectional shapes. It is another object of the present invention to provide a method and an apparatus for grinding a groove which can improve the degree of freedom in grinding the groove.

[0012]

According to the method of grinding a groove according to the present invention, a grinding wheel roller is brought into contact with an inner wall surface of an opening of a work held at a predetermined position, and the pin member is used as a rotating shaft. The whetstone roller is displaced from the upper side to the lower side of the opening along the inner wall surface of the work under the rotation of the whetstone roller. In this case, the grinding wheel roller may be displaced from the lower side to the upper side of the opening of the work.

As a result, a groove including a plurality of track grooves formed on the inner wall surface of the work, for example, the inner wall surface of the outer cup constituting the constant velocity joint can be ground.

Further, according to the present invention, the whetstone roller is displaced from one end to the other end of the work, or the whetstone roller is displaced from the other end of the work to one end. It is also possible to grind the groove on the outer wall surface of the work.

As a result, a groove portion including a plurality of ball rolling grooves formed on the outer wall surface of the work, for example, the outer wall surface of the inner race accommodated in the outer cup of the constant velocity joint can be ground.

Further, according to the groove grinding apparatus of the present invention, the main body is integrally connected to the NC machining of a robot or the like, and is provided so as to be displaceable along the three axes of XYZ. , A grinding wheel roller provided on the main body and rotatably supported via a pin member, and a driving force for transmitting a rotation driving force of the rotation driving source to the grinding wheel roller. Transmission means.

In this case, the grinding roller has a grinding portion formed on the outer peripheral surface of a disc shape, and the grinding portion is substantially horizontal from the center O when the grinding roller is viewed from a direction substantially perpendicular to the rotation axis. It may be formed in an arc shape offset by a predetermined distance in the direction.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a method for grinding a groove according to the present invention will be described in detail below with reference to the accompanying drawings.

In FIG. 1, reference numeral 20 indicates a grinding apparatus according to an embodiment of the present invention.

The grinding device 20 is connected to an NC machine, for example, an arm of a robot or the like (not shown) integrally with a main body 22 and connected substantially orthogonally to the axis of the main body 22. It has a rotary drive source 24 composed of an AC spindle motor, and a grindstone roller 30 rotatably supported by a forked portion 26 provided at the lower end of the main body 22 so as to be rotatable about a pin member 28 as a rotation center. The grinding wheel roller 30 is formed of, for example, a material such as CBN.

A drive pulley 34 is coaxially connected to a drive shaft of the rotary drive source 24 via a coupling member 32, and a timing belt 36 for transmitting a rotational force to the grindstone roller 30 is suspended on the drive pulley 34. Have been.

As shown in FIG. 2, a pin member 28 is pivotally supported on the forked portion 26 via a nut 38, and the pin member 28 is provided so as to fit into a through hole of the grinding wheel roller 30. I have. Therefore, the grinding wheel roller 30 is connected to the pin member 2.
It is provided detachably via the pin 8 and can be easily replaced with another grindstone roller (not shown) by loosening the nut 38 and removing the pin member 28.

A driven pulley 42 is externally fitted to both ends of the pin member 28 via a pair of bearing members 40a and 40b, and a timing belt 36 is suspended from one end of the driven pulley 42. . The size can be reduced by suspending the timing belt 36 only on one end side (one side) of the driven pulley 42, and grinding can be performed without bringing a portion other than the grindstone roller 30 into contact with the cup portion of the outer cup which is the work 44. Processing can be performed.

The driven pulley 42 is fitted with a grindstone roller 30 which rotates integrally with the driven pulley 42 via a cylindrical member 46. The driven pulley 42 has a pin serving as a detent. 48 is provided so as to penetrate and hold the grindstone roller 30.

Therefore, the rotational driving force of the rotational driving source 24 is
As shown in FIG. 3, the power is transmitted from the driving pulley 34 to the driven pulley 42 via the timing belt 36, and further transmitted to the grindstone roller 30 that rotates integrally with the driven pulley 42.

A bolt 50 is provided on the side of the main body 22.
And the timing belt 36
Is provided with a tension adjusting means 54 for adjusting the tension.

Below the main body 22, a jig 56 for fixing the outer cup which is the work 44 and the jig 5
6 is provided, and the jig 56 is provided with rotating means (not shown), and the work 44 is provided rotatably in the direction of arrow D under the urging action of the rotating means. Have been. The reference numeral 60 indicates that the workpiece 44 is
2 shows a fixing member for fixing the fixing member.

As shown in FIGS. 4 and 5, the grindstone roller 30 has a disk-shaped outer peripheral surface on which a grinding portion 62 is formed to move the grindstone roller 30 in a direction substantially perpendicular to the rotation axis (for example, FIG. arrow If E direction) viewed from the, the grinding section 62, a pair of arc-shaped surface 64a whose center substantially horizontally a small distance ΔX by P ₁ and the point P ₂ point offset from the center O, the 64b Formed (see FIG. 6).

The grinding apparatus 20 according to the embodiment of the present invention is basically configured as described above. Next, the operation and effect of the grinding apparatus will be described.

As the work 44, for example, a bar field type outer cup which is a molded product formed by cold forging or the like is used, and the outer cup has a cup portion 66 having an opening and a shaft portion 68. It is configured integrally (see FIG. 7). Six track grooves 70 functioning as ball rolling grooves are formed on the inner wall surface of the cup portion 66 substantially parallel to the axis, and the track grooves 70 are subjected to grinding (polishing).

First, the work 44 is loaded and fixed on a jig 56, and the rotary drive source 24 connected to a power source (not shown) is provided.
Urges the drive pulley 34 to rotate.
Is transmitted to the driven pulley 42 via the timing belt 36, and further transmitted to the grinding wheel roller 30 connected to the driven pulley 42. As a result, the grindstone roller 30 rotates in a predetermined direction about the pin member 28 as a rotation center.

Subsequently, under the turning action of the grindstone roller 30,
By controlling a robot (not shown), the grinding wheel roller 30 is moved in the XY direction so as to contact the inner wall surface of the cup portion 66 of the outer cup.
It is displaced along the three axial directions of Z. Further, by controlling a robot (not shown), the whetstone roller 30 is moved along the inner wall surface of the outer cup between the upper part and the lower part while maintaining the state of rotation at a predetermined rotation speed around the pin member 28 as a rotation center. By reciprocating, the grinding process is performed on the track groove 70 by the grindstone roller 30 (see FIG. 7). In this case, the grindstone roller 30 may be reciprocated from the upper side to the lower side of the inner wall surface of the cup portion 66, or may be reciprocated from the lower side to the upper side.

Next, the workpiece 44 is rotated by a predetermined angle in the direction of arrow D via a rotating means (not shown). Hereinafter, grinding can be performed on the remaining track grooves 70 in the same manner.

In this embodiment, the manufacturing cost can be reduced by making the whole apparatus simple. In addition, by being integrally connected to an NC machining, for example, an arm of a robot (not shown), the grindstone roller 30 can be freely displaced along the three axes of XYZ.

Further, in this embodiment, for example, by using a grindstone roller (not shown) having a square cross section,
For example, various cross-sections such as a track groove having a cross-sectional angular shape such as a V-groove or an arc-shaped track groove 70 offset from the center O by a small distance ΔX in a substantially horizontal direction as shown in FIG. A track groove having a shape can be formed, and the degree of freedom in grinding the groove can be improved.

Further, in the present embodiment, the pin member 28
Since the grindstone roller 30 can be easily replaced by removing the grindstone, the work time required for replacing the grindstone roller 30 in the production line can be shortened, and the production efficiency can be improved.

Next, FIG. 9 shows a grinding apparatus 80 according to another embodiment used for grinding (polishing) the ball rolling groove of the inner race constituting the bar field type constant velocity joint. . Note that the same components as those of the grinding device 20 according to the above-described embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

Barfield type constant velocity joint 8
2, a cup 84 and a shaft 8 as shown in FIG.
An inner cup 90 formed in the opening of the cup portion 84;
It includes a retainer 92 and six balls 93a to 93f. Track grooves 9 are provided on the outer peripheral surface of the inner race 90.
A plurality of ball rolling grooves 96a to 96f facing 4a to 94f are formed at a predetermined angle.

The grinding device 20 includes a chuck member 100 which is inserted into a through hole 98 of the inner race 90 which is a work and holds an inner surface of the work, and a chuck member 100 which is driven by an actuator (not shown). A centering member 10 which is provided so as to be able to advance and retreat, and which is centered when a tapered portion abuts on one end of the chuck member 100.
And 2. The chuck member 100 is rotatably held via a rotation mechanism 104 fixed on the bed, and the inner race 90 is provided so as to rotate integrally with the chuck member 100.

In use, the forged product of the inner race 90 formed by forging or the like is inserted into the chuck member 100.
And the inner surface thereof is held, and the taper portion of the centering member 102 is set in contact with one end of the chuck member 100.

In a state where the grindstone roller 30 is rotated about the pin member 28 as a rotation center under the driving action of the rotation drive source 24, the inner race 90 is rotated via a robot (not shown) controlled by an NC program. By displacing the grindstone roller 30 along the ball rolling grooves 96a to 96f, the ball rolling grooves 96a to 96f formed on the outer peripheral surface of the inner race 90 can be ground (polished).

The other functions and effects are the same as those of the above-described embodiment, and a detailed description thereof will be omitted.

[0043]

According to the present invention, the following effects can be obtained.

That is, the manufacturing cost can be reduced by making the entire apparatus simple.

Further, track grooves having various cross-sectional shapes can be formed, and the degree of freedom in grinding the groove portions can be improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional configuration diagram of a grinding device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a grindstone roller constituting the grinding device, taken along a substantially horizontal direction.

FIG. 3 is a perspective view of a main body including a grindstone roller.

FIG. 4 is a front view of a grindstone roller.

FIG. 5 is a longitudinal sectional view taken along line VV of FIG. 4;

FIG. 6 is a partially enlarged view as seen from a direction of an arrow E in FIG. 4;

FIG. 7 is an operation explanatory view showing a state where a track groove on an inner wall surface of the cup portion is being ground;

FIG. 8 is an explanatory view showing the shape of a track groove.

FIG. 9 is a schematic configuration diagram of a grinding device according to another embodiment of the present invention.

FIG. 10 is an explanatory diagram showing an inner race constituting the constant velocity joint.

FIG. 11 is a schematic configuration diagram of a grinding machine according to a conventional technique.

FIG. 12 is an operation explanatory view of the grinding machine shown in FIG. 11;

FIG. 13 is an explanatory view of a shape of a track groove ground by the grinding machine shown in FIG. 11;

[Explanation of symbols]

Reference numerals 20, 80: Grinding device 22: Main body 24: Rotating drive source 26: Bifurcated portion 28: Pin member 30: Grinding roller 34, 42 ... Pulley 36: Timing belt 40a, 40b ... Bearing member 44 ... Work 56: Jig 64a , 64b ...
Arc-shaped surfaces 70, 94a to 94f: track groove 90: inner race 96a to 96f: ball rolling groove 100: chuck member 102: centering member 104: rotating mechanism

Claims (6)

[Claims] 1. A method for grinding a groove formed on an inner wall surface of a work having an opening, wherein a grinding wheel roller is brought into contact with an inner wall surface of the opening of the work held at a predetermined position to rotate a pin member. Under the rotating action of the grinding wheel roller as an axis, the grinding wheel roller is displaced from the upper side of the opening to the lower side along the inner wall surface of the work, or the grinding wheel roller is moved from the lower side of the opening of the work. A groove grinding method characterized by grinding a groove on an inner wall surface of a work by displacing the groove toward an upper side. 2. A grinding method for a groove formed on an outer wall surface of a work, comprising: contacting a grindstone roller with an outer wall surface of a work held at a predetermined position; By displacing the grindstone roller from one end side of the work to the other end side under the rotating action, or displacing the grindstone roller from the other end side of the work to one end side, the outside of the work is removed. A groove grinding method characterized by grinding a groove on a wall surface. 3. The method according to claim 1, wherein the work comprises an outer cup constituting a constant velocity joint, and the groove comprises a plurality of track grooves formed on an inner wall surface of the outer cup. Grinding method. 4. The method according to claim 2, wherein the workpiece comprises an inner race accommodated in an outer cup of the constant velocity joint, and the groove comprises a ball rolling groove formed on an outer peripheral surface of the inner race. A method of grinding a groove, characterized in that: 5. A main body unit integrally connected to an NC machining of a robot or the like and provided so as to be displaceable along three axes of XYZ, a rotary drive source connected to the main body unit, and the main body unit And a grindstone roller rotatably supported by a pin member via a pin member, and a driving force transmitting means for transmitting a rotational driving force of the rotational driving source to the grindstone roller. Grinding equipment. 6. The apparatus according to claim 5, wherein the grinding roller has a grinding portion formed on a disk-shaped outer peripheral surface, and the grinding portion moves the grinding wheel roller from a direction substantially orthogonal to a rotation axis. The groove grinding device is formed in an arc shape offset from the center O by a predetermined distance in a substantially horizontal direction.