JP2002303329A - Rolling bearing and its manufacture and roll supporting structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain creeping of a rolling bearing and to reduce manufacturing costs. SOLUTION: As an outer ring 2, those which thermal processing is applied to after lathe turning and then, barrel polishing is given for finishing is used, and as an inner ring 1, those which thermal processing is applied to after lathe turning and then, barrel polishing is given, and furthermore, only the inner diameter face 7 is polished and finished is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling bearing used for supporting a roll of a copying machine, a printer, and the like, and a method of manufacturing the same, and a roll supporting structure.

[0002]

2. Description of the Related Art As a rolling bearing for supporting a roll shaft of a copying machine or a printer, a thin-walled deep groove ball bearing such as # 6805 or # 6806 is often used.
Especially since high precision is not required, JIS precision class is 0
Grade products are used. FIG. 5 shows a manufacturing process of the inner ring and the outer ring of such a deep groove ball bearing.

[0003] The JIS 0 grade products manufactured by the above-described process are the most versatile and inexpensive.

[0004]

However, in recent years, there has been a demand for further reducing the price of JIS0-grade products while strongly reducing the cost of the apparatus.
To meet such demands, the dimensional tolerance range of each part of the bearing must be widened. However, a bearing used for supporting a roll of a copying machine, a printer, or the like is usually provided with a shaft (inner ring).
Used in rotation. For this reason, in the case where the fit between the shaft and the bearing inner diameter is used with a clearance fit, if the dimensional tolerance range is widened, the clearance at the fitting portion may become large, and there is a problem that creep is likely to occur.

Rotational accuracy is one of the functions required for the roll shaft of a copying machine or a printer. The main factor that determines the rotational accuracy is the rotational accuracy (radial runout, axial runout) of a bearing that supports the roll shaft. Etc.).

At present, the rotational accuracy required for the roll shaft of a copying machine or a printer does not cause any functional problem even if a bearing having an accuracy lower than JIS0 class is used as a support bearing.

[0007] The factors that determine the rotational accuracy of the bearing are mainly determined by the accuracy of the transfer surface dimensions, roundness, surface waviness, surface roughness, and the like of the inner and outer rings. The precision required for the inner ring and outer ring eliminates grinding and superfinishing, and even the precision obtained by the barrel polishing described above, the rotation required for bearings used in roll shafts of copiers and printers There is no problem in accuracy.

Similarly, since the dimensions and accuracy of the outer ring outer diameter surface, outer ring width surface, and inner ring width surface do not require JIS0 class accuracy, grinding and super finishing of grooves are abolished, and impacts such as barrel polishing are eliminated. It is possible to change to polishing.

Accordingly, an object of the present invention is to provide a rolling bearing which minimizes the production cost while minimizing the occurrence of creep, a method of manufacturing the same, and a roll supporting structure using the rolling bearing.

[0010]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a rolling bearing having a rolling element held by a retainer between an inner ring and an outer ring, wherein the inner ring and the outer ring are The heat treatment is performed after the turning, and then the one finished by impact polishing such as barrel polishing is used. As the inner ring, it is possible to use an inner ring which is finished by grinding only the inner diameter surface after impact polishing such as the above-mentioned barrel polishing.

The turning of the outer ring is performed on all surfaces such as the outer diameter surface, the width surface and the rolling surface, and the turning of the inner ring is performed on all surfaces such as the inner diameter surface, the width surface and the rolling surface. Is done. After performing a predetermined heat treatment, the inner ring and the outer ring are subjected to impact polishing such as barrel polishing. Thereafter, only the inner diameter surface of the inner ring is subjected to grinding to finish to JIS accuracy class 0.

Applications of the above-mentioned rolling bearing include a roll supporting structure for a copying machine, a printer and the like. For example, in a copying machine, it is used as a rolling bearing that rotatably supports a heating roll of a fixing unit with respect to a housing.

Since the rolling bearing having the above-described structure is finished with an accurate inner diameter, the clearance between the rolling bearing and the shaft is reduced, and the occurrence of creep is suppressed. In addition, since processing is performed by impact polishing such as barrel polishing instead of grinding and superfinishing, processing costs are greatly reduced.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings. As shown in FIG. 1, the deep groove ball bearing according to the embodiment includes an inner ring 1, an outer ring 2, a required number of balls 3 interposed therebetween, and a retainer 4 for holding each ball 3 at a constant interval. You. Rolling surfaces 5 and 6 are formed on opposing surfaces of the inner ring 1 and the outer ring 2, respectively.

FIG. 2 shows a process of manufacturing the inner ring 1 and the outer ring 2 described above. The inner ring 1 has an inner diameter surface 7 after forging.
Turning is performed on the entire surface such as the width surfaces 8, 8 and the rolling surface 5,
After the heat treatment, barrel polishing is performed. Further, the inner diameter surface 7 is subjected to a grinding process, and is finished to a class 0 with JIS accuracy. In addition, the outer race 2 is subjected to turning on the inner diameter surface 9, the width surfaces 10, 10 and the rolling surface 6 after forging,
After the heat treatment, the barrel is polished and finished.

The barrel polishing performed on the inner ring 1 or the outer ring 2 is performed by, for example, placing the inner ring 1 or the outer ring 2 to be polished in a polygonal barrel (barrel-shaped container) such as a hexagon or an octagon.
, A medium, a compound (abrasive), silica sand, water, etc. are charged at the same time, and the barrel is rotated, vibrated, centrifuged,
This is a method in which the surface is fine-finished by adding a motion such as spin to the object to be polished or the medium relative to each other or by collision of the medium with an inner ring (or an outer ring). After the barrel polishing, the inner ring 1 or the outer ring 2 is subjected to washing such as water washing or ultrasonic washing to remove adhered substances such as media, compounds (abrasives), and metal powder on the surface.
As the media, for example, alumina (aluminum oxide)
Or silicon oxide can be used. The polishing conditions including the hardness of the medium, the type of the medium, the rotation speed of the barrel, the processing time, and the like are appropriately determined depending on the material and size of the object to be polished.

By this means, the oxide scale on the surface caused by the heat treatment is removed, and the deformation generated during the quenching step of the heat treatment is removed, so that the smooth surface roughness and shape deformation with less irregularities than after the heat treatment step are obtained. It is possible to obtain less inner ring 1 or outer ring 2. The surface roughness of the inner ring 1 and the outer ring 2 after barrel polishing has a center line average roughness of 0.1 μm Ra.
Surface roughness of about 1.0 μmRa can be obtained.
Barrel polishing is a very inexpensive processing method because a large amount of objects to be polished can be processed at one time.

In the present invention, barrel polishing has been described in the above description. However, as other impact polishing methods, vibration polishing, shot blast, air blast and the like can be applied. The shaft 11 is fitted to the inner diameter surface 7 of the inner race 1 without any gap.

An example of the dimensional difference of each part of the bearing is as follows.

When the inner diameter grinding is not performed after the barrel polishing, the dimensional difference of the inner diameter φB of the inner ring 1 is 0 to −0.0.
050 mm. On the other hand, in the embodiment according to claim 2 of the present invention, the dimensional difference of the outer diameter φA of the outer race 2 is 0 to −0.1.
0 mm, the dimensional difference of the inner diameter φB of the inner ring 1 is 0 to -0.01
mm, the width C of the outer ring 2 and the inner ring 1 is 0 to -0.12 mm. The tolerance range of the inner diameter φB is equivalent to JIS0 class.
By finishing the inner diameter φB of the inner ring 1 with high accuracy, the tolerance range can be suppressed, and the clearance between the inner diameter of the inner ring 1 and the shaft 11 can be reduced. As a result, inner ring 1
Creep between the inner diameter of the shaft and the shaft 11 can be suppressed.

Next, as an example of the application of the above-mentioned rolling bearing, an example used in an electrostatic transfer copying machine will be described. FIG.
Is a case of an electrostatic transfer copying machine provided with a quadruple tandem type photosensitive drum 12, and the photosensitive drum 1 is
When an electric charge is given to 2 and exposure is performed by the polygon scanner motor 14, an electric charge according to the intensity of light forms an electrostatic latent image on the photosensitive drum 12. Here, the toner having the opposite polarity charge is supplied from the developing unit 15 and adheres to form a visible image. The visible image is transferred to the intermediate transfer body 16 and further transferred from the intermediate transfer body 16 to the paper 17. The paper 17 is sent to the fixing unit 18, where the paper 17 is heated and pressed to fix the toner on the paper.

The fixing section 18 has a heating roll 18a, a fixing roll 18b, and a pressurizing / heating roll 18c. A resin sheet 18d made of polyimide or the like is hung on the heating roll 18a and the fixing roll 18b. Is transmitted to the paper 17 via the resin sheet 18d. A heater is provided in each of the heating roll 18a and the pressurizing / heating roll 18c.

As shown in FIG. 4, the rolling bearing 19 according to the embodiment of the present invention is used as a bearing having a roll support structure for rotatably supporting the heating roll 18a with respect to the housing 20. The rolling bearing 19 includes an inner race 21 fitted to the shaft end of the heating roll 18a, an outer race 22 fitted to the inner periphery of the housing 20, a rolling surface 23 of the inner race 21, and a rolling surface of the outer race 22. 24, a required number of balls 25 interposed between the balls 24, and a cage 2 for maintaining a space between the balls 25.
6 and a pair of seals 27, 27. Further, the current-carrying grease 28 is sealed inside the bearing. Heating roll 18
A heater 29 is provided inside a.

The inner ring 21 and the outer ring 22 of the above-mentioned rolling bearing 19 are manufactured by the above-described processing method (see FIG. 2).

[0025]

As described above, according to the present invention, it is possible to provide a rolling bearing with low creep with the shaft and low manufacturing cost, which contributes to reduction of the cost of a copying machine, a printer and the like. it can.

[Brief description of the drawings]

FIG. 1 is a partially enlarged sectional view of a rolling bearing according to an embodiment;

FIG. 2 is a manufacturing process diagram of the above.

FIG. 3 is a schematic diagram of an electrostatic transfer copying machine as an example of use.

FIG. 4 is an enlarged sectional view of a heating roll part of FIG. 3;

FIG. 5 is a manufacturing process diagram of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inner ring 2 Outer ring 3 Ball 4 Cage 5 Rolling surface 6 Rolling surface 7 Inner diameter surface 8 Width surface 9 Outer diameter surface 10 Width surface 11 Axis

Continued on the front page F term (reference) 2H033 AA21 AA23 BB36 2H071 BA03 BA27 CA05 DA12 DA26 3J101 AA02 AA32 AA42 AA52 AA62 BA53 BA54 DA11 FA35 FA44 GA42 GA53 3J103 AA02 BA46 CA62 FA26 GA02 GA57 GA58

Claims (6)

[Claims] 1. A rolling bearing in which a rolling element held by a cage is interposed between an inner ring and an outer ring, wherein the inner ring and the outer ring are subjected to a heat treatment after turning and then subjected to impact polishing such as barrel polishing. A rolling bearing, characterized in that it is provided. 2. The rolling bearing according to claim 1, wherein the inner race is finished by grinding only the inner surface after impact polishing such as barrel polishing. 3. The rolling bearing according to claim 1, wherein an inner diameter surface of the inner ring is finished to JIS accuracy class 0. 4. A method for manufacturing a rolling bearing in which a rolling element held by a retainer is interposed between an inner ring and an outer ring,
A method for manufacturing a rolling bearing, wherein the inner ring and the outer ring are processed by performing a heat treatment after the turning and then performing an impact polishing such as a barrel polishing. 5. The method for manufacturing a rolling shaft according to claim 4, wherein the inner ring is processed by finishing only the inner diameter surface after impact polishing such as barrel polishing. 6. In a roll supporting structure of a copying machine, a printer, or the like, in which a roll is rotatably supported by a rolling bearing, at least rolling of a surface of at least one of the inner races or the outer races of the races of the rolling bearing. A roll support structure characterized in that the surface is finished by impact polishing such as barrel polishing.