JP7035383B2 - Grinding device and grinding method for ring-shaped members, and manufacturing method for radial bearings - Google Patents

Description

The present invention relates to a grinding device for grinding an outer peripheral surface of a metal ring-shaped member such as an inner ring constituting a radial rolling bearing.

Improved surface accuracy and surface roughness on the outer peripheral surface of metal ring-shaped members such as the inner ring track of the inner ring and the outer peripheral surface of the outer ring, the outer peripheral surface of the slide bearing, and the cylindrical fitting surface that make up the radial rolling bearing. Grinding is applied to make it. 5 and 6 show the structure of the grinding apparatus 1 described in Japanese Patent Application Laid-Open No. 2004-195651. The grinding device 1 can perform so-called coreless grinding on the outer peripheral surface of the ring-shaped member 6 without supporting the inner peripheral surface of the ring-shaped member 6 or gripping the outer peripheral surface with a chuck. It is a board. Such a grinding device 1 is made of a rotary drive shaft 3 having a backing plate 2 at its tip, a grindstone 5 having a rotary shaft 4 parallel to the rotary drive shaft 3, and a metal work piece. A pair of shoes 7a and 7b for positioning the ring-shaped member 6 in the radial direction are provided.

When grinding the outer peripheral surface of the ring-shaped member 6, the ring-shaped member 6 is supported on the tip surface of the backing plate 2, and the tip portions of a pair of shoes 7a and 7b are supported on the outer peripheral surface of the ring-shaped member 6. Is brought into contact with each other to position the ring-shaped member 6 in the radial direction. In this state, by rotationally driving the rotary drive shaft 3, the grinding surface 8 which is the outer peripheral surface of the grindstone 5 which rotates around the rotary shaft 4 while rotationally driving the ring-shaped member 6 is formed on the ring-shaped member 6. By pressing against the outer peripheral surface, the outer peripheral surface of the ring-shaped member 6 is ground.

Japanese Unexamined Patent Publication No. 2004-195651

In coreless grinding, the grindstone 5 is pressed against the outer peripheral surface of the ring-shaped member 6, so that the ring-shaped member 6 is elliptical as shown in FIG. 7 (B) from the state shown in FIG. 7 (A). Elastically deforms to. Such elastic deformation becomes more remarkable as the rigidity of the ring-shaped member 6 in the radial direction becomes smaller. When the ring-shaped member 6 is elastically deformed, of the pair of shoes 7a and 7b, the tip surface of the first shoe 7a on the side closer to the grindstone 5 with respect to the pressing direction of the grindstone 5 and the outer peripheral surface of the ring-shaped member 6 The contact pressure of the first shoe 7a becomes small, and in a remarkable case, the tip surface of the first shoe 7a and the outer peripheral surface of the ring-shaped member 6 are separated from each other. If the contact pressure between the tip surface of the first shoe 7a and the outer peripheral surface of the ring-shaped member 6 becomes smaller during the grinding process, the posture of the ring-shaped member 6 becomes unstable and the outer peripheral surface of the ring-shaped member 6 becomes unstable. There is a possibility of chattering.

In view of the above circumstances, it is an object of the present invention to provide a means capable of effectively preventing chattering from occurring on the outer peripheral surface of the ring-shaped member.

The ring-shaped member grinding device of the present invention is for grinding the outer peripheral surface of a metal ring-shaped member, and includes a rotary drive shaft, a grindstone, and a pair of shoes.
The rotation drive shaft is for rotationally driving the ring-shaped member.
The grindstone is pressed against the outer peripheral surface of the ring-shaped member in order to grind the outer peripheral surface of the ring-shaped member.
The pair of shoes each supports a portion of the outer peripheral surface of the ring-shaped member that is deviated from the portion ground by the grindstone in the circumferential direction.
When the outer peripheral surface of the ring-shaped member is ground by the grindstone, the outer peripheral surface of the ring-shaped member is the first shoe of the pair of shoes on the side closer to the grindstone. Apply a moment in the direction of pressing toward.

The force applied to the ring-shaped member from the end portion of the pair of shoes far from the first shoe on the radial inner surface of the second shoe far from the grindstone is applied to the first shoe. It can be larger than the force applied to the ring-shaped member from the end on the side closer to the shoe.

The second shoe can swing around a swing shaft arranged in parallel with the rotation drive shaft, and the swing shaft can be moved from the center position in the circumferential direction of the second shoe. Also, it can be positioned on the side far from the first shoe in the circumferential direction.

The second shoe may have a pair of work support portions protruding inward in the radial direction at both ends in the circumferential direction of the inner surface in the radial direction.

In the method of grinding a ring-shaped member of the present invention using the grinding device of the ring-shaped member of the present invention, the rotary drive shaft is set in a state where the ring-shaped member is positioned in the radial direction by the pair of shoes. By rotationally driving the ring-shaped member, the grindstone is pressed against the outer peripheral surface of the ring-shaped member while the ring-shaped member is rotationally driven, thereby grinding the outer peripheral surface of the ring-shaped member.

In the method for manufacturing a radial bearing of the present invention, the outer peripheral surface of any of the members constituting the radial bearing is ground by the method for grinding the ring-shaped member of the present invention as described above. Specifically, a plurality of radial bearings are rotatably arranged between an inner ring having an inner ring track on the outer peripheral surface, an outer ring having an outer ring track on the inner peripheral surface, and the inner ring track and the outer ring track. A radial rolling bearing including a rolling element, and any of the above members is referred to as an inner ring or an outer ring. The radial rolling bearings that can be the subject of the present invention are not limited to ball bearings such as deep groove type and angular type, but also include cylindrical roller bearings and tapered roller bearings. Alternatively, the radial bearing may be a radial slide bearing. The radial bearing obtained by the method for manufacturing a radial bearing of the present invention can be used by being incorporated into various mechanical devices such as automobiles and machine tools.

According to the present invention, it is possible to effectively prevent chattering from occurring on the outer peripheral surface of the ring-shaped member.

FIG. 1 is a side view showing a first example of an embodiment of the present invention. FIG. 2 is a side view showing a second example of the embodiment of the present invention. FIG. 3 is a side view showing the structure of the grinding device of the comparative example. FIG. 4A is a diagram showing the cross-sectional shape of the outer peripheral surface of the ring-shaped member of the embodiment by the magnitude of the error with respect to the least squares average circle, and FIG. 4B is a diagram showing the ring-shaped member of the comparative example. It is a figure which represented the cross-sectional shape of the outer peripheral surface of the above with the magnitude of the error with respect to the least squares average circle. FIG. 5 is a side view showing an example of a conventional structure of a ring-shaped member grinding device. FIG. 6 is a plan view showing a state seen from above of FIG. FIG. 7A is a side view showing a state before the grindstone is pressed against the ring-shaped member, and FIG. 7B is an exaggerated side view showing a state in which the grindstone is pressed against the ring-shaped member.

[First example of the embodiment]
FIG. 1 shows a first example of an embodiment of the present invention. The grinding device 1a of this example is a so-called coreless grinding machine for grinding the outer peripheral surface of a metal ring-shaped member 6 which is a workpiece, and has a rotary drive shaft 3 (see FIG. 5) and a grindstone 5. And a pair of shoes 7c and 7d.

The rotary drive shaft 3 can be rotationally driven by a drive source such as an electric motor, and has a backing plate 2 at its tip. In this example, the rotation drive shaft 3 is arranged in the horizontal direction. The ring-shaped member 6 is supported coaxially with the rotary drive shaft 3 by magnetically attracting the axial side surface to the tip surface of the backing plate 2.

The grindstone 5 has a cylindrical grinding surface 8 on the outer peripheral surface and a rotating shaft 4 (see FIGS. 5 and 6) parallel to the rotating drive shaft 3 at the center thereof. That is, the grindstone 5 can be rotationally driven around the rotary shaft 4. Further, the rotary shaft 4 is capable of radial perspective movement with respect to the rotary drive shaft 3. That is, the grinding surface 8 can be pressed against the outer peripheral surface of the ring-shaped member 6 supported by the rotary drive shaft 3. In this example, the grinding surface 8 can be pressed against one end in the horizontal direction (right end in FIG. 1) of the outer peripheral surface of the ring-shaped member 6.

The pair of shoes 7c and 7d are positioned with respect to the radial direction of the ring-shaped member 6 by allowing the tip portions thereof to be in contact with the outer peripheral surface of the ring-shaped member 6 so as to be slidable in the circumferential direction. Is for.

Of the pair of shoes 7c and 7d, the first shoe (front shoe) 7c on the side closer to the grindstone 5 (right side in FIG. 1) with respect to the pressing direction of the grindstone 5 (grinding surface 8) against the outer peripheral surface of the ring-shaped member 6. Is installed on the radial outer side of the vertical lower side of the horizontal one side of the ring-shaped member 6.

Further, the first shoe 7c has a diameter at the end portion of the inner surface surface in the radial direction, which is closer to the contact portion (sliding contact portion) between the outer peripheral surface of the ring-shaped member 6 and the ground surface 8 in the circumferential direction. It has a work support portion 9a protruding inward in the direction, and has a diameter at the end portion of the inner surface surface in the radial direction far from the contact portion between the outer peripheral surface of the ring-shaped member 6 and the grinding surface 8 in the circumferential direction. It has a work support portion 9b protruding inward in the direction.

Of the pair of shoes 7c and 7d, the second shoe (rear shoe) 7d on the side farther from the grindstone 5 (left side in FIG. 1) with respect to the pressing direction of the grindstone 5 against the outer peripheral surface of the ring-shaped member 6 is the ring-shaped member 6. It is installed on the outer side in the radial direction of the lower side in the vertical direction of the other side in the horizontal direction (left side in FIG. 1).

Further, the second shoe 7d has a work support portion 9c protruding inward in the radial direction at an end portion of the inner side surface in the radial direction closer to the first shoe 7c in the circumferential direction, and has a radial direction. A work support portion 9d projecting inward in the radial direction is provided at an end portion of the inner side surface on the side far from the first shoe 7c in the circumferential direction.

The work support portions 9a to 9d are positioned in the radial direction of the ring-shaped member 6 by contacting (sliding) the respective tip portions with the outer peripheral surface of the lower half portion of the ring-shaped member 6. For this reason, the central axis of the cylindrical surface in contact with the respective tip portions of the work support portions 9a to 9d is slightly eccentric in the horizontal direction with respect to the central axis of the rotary drive shaft 3. As a result, during the grinding process of the outer peripheral surface of the ring-shaped member 6, the surface pressure of the contact portion between the respective tip portions of the work support portions 9a to 9d and the outer peripheral surface of the ring-shaped member 6 can always be generated. can.

Further, each of the pair of shoes 7c and 7d has a swing shaft 10a and 10b parallel to the rotation drive shaft 3, and can swing around the swing shafts 10a and 10b, respectively. With such a configuration, the work support portions 9a to 9d are made to follow the diameter reduction of the outer peripheral surface of the ring-shaped member 6 as the grinding process progresses, and even when the outer peripheral surface of the ring-shaped member 6 is reduced in diameter, the ring is formed. Positioning of the shape member 6 in the radial direction can be achieved.

In this example, the first shoe 7c has a swing shaft 10a at the center position in the circumferential direction. However, the first shoe 7c may have a configuration that does not have a swing shaft 10a, that is, a configuration that cannot swing.

On the other hand, the second shoe 7d has a swing shaft 10b at a position farther from the first shoe 7c in the circumferential direction than the center position in the circumferential direction. That is, the reference line L ₀ orthogonal to the central axis O 6 of the ring-shaped member ₆ and the central axis O _10b of the swinging shaft 10b, and the ring-shaped member 6 orthogonal to the central axis O ₆ of the ring-shaped member 6. The angle θ ₁ formed by the virtual straight line L ₁ passing through the contact portion between the outer peripheral surface of the work and the tip end portion of the work support portion 9c is orthogonal to the reference line L ₀ and the central axis O ₆ of the ring-shaped member 6. The angle formed by the virtual straight line L ₂ passing through the contact portion between the outer peripheral surface of the ring-shaped member 6 and the tip end portion of the work support portion 9d is larger than the angle θ ₂ (θ ₁ > θ ₂ ).

Further, the positional relationship between the first shoe 7c and the second shoe 7d in the circumferential direction is regulated as follows. That is, the angle φ formed by the virtual straight line _LA orthogonal to the central axis O 6 of the ring-shaped member ₆ and the central axis O ₁₀ of the swing axis 10a and the reference line L ₀ is smaller than 180 degrees. (Φ <180).

When grinding the outer peripheral surface of the ring-shaped member 6 using the grinding device 1a of this example, first, the ring-shaped member 6 is magnetically attracted to the tip surface of the backing plate 2 to form a ring. The shape member 6 supports rotation coaxially with the rotation drive shaft 3 and in synchronization with the rotation drive shaft 3. Further, the tip portions of the work support portions 9a to 9d are brought into contact with the outer peripheral surface of the lower half portion of the ring-shaped member 6 to position the ring-shaped member 6 in the radial direction. In this state, by rotationally driving the rotary drive shaft 3, the ring-shaped member 6 is rotationally driven, and at one end of the ring-shaped member 6 in the horizontal direction, centered on the rotary shaft 4, and the ring-shaped member 6 By pressing the grinding surface 8 of the grindstone 5 that rotates in the direction opposite to the rotation direction of the ring-shaped member 6, the outer peripheral surface of the ring-shaped member 6 is ground.

According to this example as described above, it is possible to effectively prevent chattering from occurring on the outer peripheral surface of the metal ring-shaped member 6. The reason for this will be described below.

When the outer peripheral surface of the ring-shaped member 6 is ground, when the grinding surface 8 of the grindstone 5 is pressed against one end of the outer peripheral surface of the ring-shaped member 6 in the horizontal direction, it is below the other side of the ring-shaped member 6 in the horizontal direction. The outer peripheral surface of the half portion is pressed against the respective tip portions of the work support portions 9c and 9d of the second shoe 7d. In this example, the swing shaft 10b of the second shoe 7d is arranged at a position farther from the center position in the circumferential direction of the second shoe 7d with respect to the first shoe 7c in the circumferential direction. ing. Therefore, as the outer peripheral surface of the lower half of the other side of the ring-shaped member 6 in the horizontal direction is pressed against the respective tip portions of the work support portions 9c and 9d, the work support portion 9d joins the ring-shaped member 6. The reaction force Fr ₂ becomes larger than the reaction force Fr ₁ applied to the ring-shaped member 6 from the work support portion 9c (Fr ₂ > Fr ₁ ). Therefore, the direction in which the lower peripheral surface of the lower half portion of the horizontal one-sided portion of the ring-shaped member 6 is pressed against the ring-shaped member 6 toward the respective tips of the work support portions 9a and 9b of the first shoe 7c. Moment M is added. Therefore, even when the ring-shaped member 6 is elastically deformed into an elliptical shape by pressing the grinding surface 8 of the grindstone 5 against the outer peripheral surface of the ring-shaped member 6, the work support portions 9a and 9d of the first shoe 7c and the ring It is possible to prevent the shape member 6 from being separated from the outer peripheral surface. As a result, the posture of the ring-shaped member 6 during grinding can be stabilized, chattering can be effectively prevented from being formed on the outer peripheral surface of the ring-shaped member 6, and the roundness of the ring-shaped member 6 can be reduced. Can be improved.

In the case of carrying out the present invention, the work support portion is not provided on the radial inner surface of the pair of shoes, and the radial inner surface of the pair of shoes is defined as the radius of curvature of the outer peripheral surface of the ring-shaped member. It can also be a partially cylindrical concave curved surface having the same radius of curvature. It should be noted that convex portions protruding inward in the radial direction are provided at a plurality of points in the circumferential direction of the inner surface surface of the pair of shoes in the radial direction, and the tip surface of the convex portion is the radius of curvature of the outer peripheral surface of the ring-shaped member. It can also be a partially cylindrical concave curved surface having the same radius of curvature as. Even in this case, the swing axis of the second shoe is installed at a position farther from the first shoe in the circumferential direction than the center position in the circumferential direction. As a result, the force applied to the ring-shaped member from the end portion of the radial inner surface of the second shoe far from the first shoe is applied to the ring-shaped member from the end portion closer to the first shoe. It can be made larger than the force, and a moment in the direction of pressing the outer peripheral surface of the ring-shaped member toward the radial inner surface of the first shoe can be applied to the ring-shaped member.

[Second example of the embodiment]
FIG. 2 shows a second example of an embodiment of the present invention. In the grinding device 1b of this example, the second shoe 7e, which is a rear shoe, has a swing shaft 10c parallel to the rotation drive shaft 3 at the center position in the circumferential direction. Further, in this example, the second shoe 7e is given elasticity in the direction of rotating the second shoe 7e in the clockwise direction of FIG. 2 (direction of arrow α in the figure). As a result, the force Fr ₂ applied to the ring-shaped member from the work support portion 9d is made larger than the force Fr ₁ applied to the ring-shaped member 6 from the work support portion 9c. As a result, the outer peripheral surface of the lower half of the horizontal one-sided portion of the ring-shaped member 6 is pressed against the ring-shaped member 6 toward the respective tips of the work support portions 9a and 9b of the first shoe 7a. The moment M in the direction acts. The composition and action of other parts are the same as those of the first embodiment.

In the case of carrying out the present invention, the structure for applying a moment in the direction of pressing the outer peripheral surface of the ring-shaped member toward the tip of the first shoe, which is the front shoe, on the ring-shaped member is implemented. As in the first and second examples of the embodiment, the structure is not limited to the structure in which the pivot shoe that can swing around the swing axis is used as the second shoe that is the rear shoe. Specifically, for example, the second shoe may be supported by a ball joint, or may be provided with elasticity in the radial, horizontal, or vertical directions by an elastic member such as a coil spring. In any structure, during the grinding process of the outer peripheral surface of the ring-shaped member, a moment in the direction of pressing the outer peripheral surface of the ring-shaped member toward the tip of the first shoe, which is the front shoe, can be applied. As described above, the installation mode of the second shoe, the displaceable direction, the magnitude of the elasticity to be applied, and the like are appropriately regulated.

An experiment conducted to confirm the effect of the present invention will be described. In this experiment, when the outer peripheral surface of the ring-shaped member 6 is ground by a grinding device belonging to the technical range of the present invention and when the outer peripheral surface is ground by a grinding device outside the technical range of the present invention. Then, the roundness of the cross-sectional shape of the outer peripheral surface of the ring-shaped member after the grinding process was measured. In the embodiment, the grinding device 1a of the first example of the embodiment shown in FIG. 1 was used. On the other hand, in the comparative example, the grinding apparatus 1c outside the technical scope of the present invention as shown in FIG. 3 was used. That is, in the grinding apparatus 1c, the second shoe 7f, which is the rear shoe, has the swing shaft 10d at a position closer to the first shoe 7c in the circumferential direction than the center position in the circumferential direction. There is. The specifications of the ring-shaped member 6 and the grinding devices 1a and 1c are as follows.

"Ring-shaped member 6"
Material: High carbon chrome bearing steel (SUJ2)
Outer diameter: 101 mm
Width: 13 mm
"Grinding device 1a"
Angle θ ₁ : Approximately 15 degrees Angle θ ₂ : Approximately 10 degrees “Grinding device 1c”
Angle θ ₁ : Approximately 10 degrees Angle θ ₂ : Approximately 15 degrees

The circumferential positions of the pair of shoes 7c and 7d constituting the grinding device 1a of the embodiment and the circumferential positions of the pair of shoes 7c and 7f constituting the grinding device 1c of the comparative example. Are in agreement with each other.

Regarding the cross-sectional shape of the outer peripheral surface of the ring-shaped member 6 after the completion of grinding, three peak components were taken out by harmonic analysis and the amplitude was measured. In the example, it was about 0.2 [μm], which is a comparative example. Then, it was about 0.5 μm. Note that FIG. 4A is a diagram showing the cross-sectional shape of the outer peripheral surface of the ring-shaped member 6 of the embodiment by the magnitude of the error with respect to the least squares average circle, and FIG. 4B is a comparative example. It is a figure which showed the cross-sectional shape of the outer peripheral surface of a ring-shaped member 6 in the same manner.

Examples of the ring-shaped member to be the subject of the present invention include an inner ring and an outer ring constituting a radial rolling bearing, a radial sliding bearing, and a member having a cylindrical fitting surface on the outer peripheral surface. When the ring-shaped member is an inner ring of a radial rolling bearing, it is preferable to grind the inner ring track and the outer peripheral surface of the shoulder at the same time by using a so-called total type grindstone as the grindstone. However, it is also possible to separately grind the inner ring track and the outer peripheral surface of the shoulder portion.

1, 1a, 1b, 1c Grinding device 2 Backing plate 3 Rotating drive shaft 4 Rotating shaft 5 Grindstone 6 Ring-shaped member 7a, 7b, 7c, 7d, 7e, 7f Shoe 8 Grinding surface 9a-9d Work support 10a, 10b, 10c swing shaft

Claims (6)

A rotary drive shaft for rotationally driving a metal ring-shaped member,
A grindstone pressed against the outer peripheral surface of the ring-shaped member in order to grind the outer peripheral surface of the ring-shaped member.
It is provided with a pair of shoes that support each portion of the outer peripheral surface of the ring-shaped member that deviates from the portion ground by the grindstone in the circumferential direction.
When the outer peripheral surface of the ring-shaped member is ground by the grindstone, the outer peripheral surface of the ring-shaped member is the first shoe of the pair of shoes on the side closer to the grindstone. A moment in the direction of pushing toward the whetstone is applied ,
The force applied to the ring-shaped member from the end portion of the pair of shoes far from the first shoe on the radial inner surface of the second shoe far from the grindstone is the first force. It is larger than the force applied to the ring-shaped member from the end near the shoe of the wheel.
Grinding device for ring-shaped members. The second shoe can swing around a swing shaft arranged in parallel with the rotation drive shaft.
The swing axis is located on the side farther from the first shoe in the circumferential direction than the center position in the circumferential direction of the second shoe.
The grinding device for a ring-shaped member according to claim 1 . The ring-shaped member grinding apparatus according to claim 1 or 2 , wherein the second shoe has a pair of work support portions protruding inward in the radial direction at both ends in the circumferential direction of the inner surface in the radial direction. A method for grinding a ring-shaped member using the ring-shaped member grinding device according to any one of claims 1 to 3 .
By rotationally driving the rotation drive shaft in a state where the ring-shaped member is positioned in the radial direction by the pair of shoes, the ring-shaped member is rotationally driven and is mounted on the outer peripheral surface of the ring-shaped member. A method for grinding a ring-shaped member, which grinds the outer peripheral surface of the ring-shaped member by pressing the grindstone. The outer peripheral surface of any of the members constituting the radial bearing is ground by the method for grinding the ring-shaped member according to claim 4 .
How to manufacture radial bearings. The radial bearing includes an inner ring having an inner ring track on the outer peripheral surface, an outer ring having an outer ring track on the inner peripheral surface, and a plurality of rolling elements rotatably arranged between the inner ring track and the outer ring track. It is a radial rolling bearing equipped with
Any of the members is the inner ring or the outer ring.
The method for manufacturing a radial bearing according to claim 5 .

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