JPH08284959A - Bearing device - Google Patents

Abstract

PURPOSE: To prevent the temperature rise of a bearing by the frictional heat to be generated between the bearing and a shaft. CONSTITUTION: A bearing 49 consists of an outer cylindrical part 49a which is fitted to a fitting hole 50 of a supporting member and tightened and held by the supporting member, an inner cylindrical part 49b having a bearing hole, and a rib part 49c to connect the cylindrical parts. The outer cylindrical part 49a of the bearing 49 is fitted to a fitting hole 50 of the supporting member, the inner cylindrical part 49b is supported by the rib part 49c between clearances 55, and a roller shaft 53 is passed through and supported by the bearing hole of the inner cylindrical part 49b. When the roller shaft 53 is driven, the frictional heat to be generated between the bearing 49 and the roller shaft 53 is dissipated outside through the clearances 55.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing device for rotatably supporting a rotating shaft or slidably supporting a sliding shaft in, for example, a copying machine, a printer, a facsimile, a printing machine or the like.

[0002]

2. Description of the Related Art Conventionally, in this type of bearing device, a bearing is provided with a fitting portion and a bearing hole is provided at the center thereof.

Then, such a bearing has been mounted by press-fitting the fitting portion into the mounting hole of the support member or by sandwiching the fitting portion between two support members.

[0004]

Therefore, in the worst case, the outer diameter of the fitting portion of the bearing may become larger than the mounting hole of the support member due to variations in accuracy.

Therefore, in the conventional bearing device, the bearing hole is deformed by the strong force that tightens the fitting portion to deteriorate the movement of the shaft, and the frictional heat generated between the bearing and the shaft is increased to raise the temperature of the bearing. There was a problem. As a result, for example, the wear of the bearing hole is accelerated and the life of the bearing is shortened.

Therefore, an object of the present invention is to prevent the temperature of the bearing from rising due to frictional heat generated between the bearing and the shaft.

[0007]

Therefore, the present invention provides
For example, as in the following embodiment shown in the drawings, a bearing device that fits a bearing 49 into a mounting hole 50 of a supporting member such as the developing case 35 and supports a shaft such as a roller shaft 53 through a bearing hole 49e of the bearing 49. In the above, the bearing 49 includes an outer cylindrical portion 49a fitted into the mounting hole 50 and clamped and held by the support member, an inner cylindrical portion 49b having the bearing hole 49e, and a rib portion 49c connecting them. It is characterized by that.

According to a second aspect of the present invention, for example, as in the embodiments of FIGS. 5 and 6 below, in the bearing device of the first aspect, the rib portion 49c is one.
It is characterized by the following.

According to a third aspect of the present invention, the upper case 44 and the lower case 4 which constitute the supporting member such as the developing case 35, for example, as shown in FIGS. 7 and 8 below.
The bearing device according to claim 1, wherein the mounting hole 50 is formed by superposing two constituent parts such as No. 5, and the bearing 49 fitted in the mounting hole 50 is sandwiched and held by the two constituent parts. In addition, the support member is provided with a positioning portion 50a that determines the rotational position of the bearing 49, and the rib portion 49c is provided in the diametrical direction in a direction orthogonal to the direction in which the two constituent portions are overlapped. Is characterized by.

According to a fourth aspect of the present invention, for example, as in the following embodiment of FIG. 9, in the bearing device according to the first aspect, the outer circumference of the inner cylindrical portion 49b is directed from the inner side to the outer side. It is characterized in that a taper surface 49g that gradually increases is formed.

According to a fifth aspect of the present invention, the bearing device according to the first aspect is used in a developing device as in the embodiment shown in FIG. 10 below. It is characterized in that a tapered surface 49h that gradually increases from the outside to the outside is formed.

According to a sixth aspect of the present invention, in a bearing device according to the first aspect, which is used in a developing device, for example, as in the following embodiment shown in FIG. 11, a first portion is provided at an inner end of the outer cylindrical portion 49a. The outer periphery of the seal member 57 is tightly adhered to the center hole 57a.
Pass the shaft through the second seal member 58.
Is press-fitted and the seal portion 58a of the second seal member 58 is elastically pressed against the inside of the first seal member 57.

[0013]

In the present invention, the mounting hole 50 for the support member is provided.
The outer tubular portion 49a of the bearing 49 is fitted into the bearing, and the shaft is supported through the bearing hole 49e of the inner tubular portion 49b supported by the rib portion 49c between the gaps 55.

According to the second aspect, one rib portion 49c supports the inner tubular portion 49b.

According to the third aspect of the present invention, the mounting hole 50 is formed by superposing the two components, and at this time, the positioning portion 50a determines the rotational position of the mounting hole 50 and mounts the bearing 49. It is sandwiched and held by two components.

According to the fourth aspect of the present invention, for example, when the bearing 49 is lubricated, the oil introduced through the void 55 flows inward along the tapered surface 49g.

According to the fifth aspect, for example, when the developer enters the bearing 49, the developer slides on the tapered surface 49h and moves outward.

According to the sixth aspect, when the shaft is rotationally driven, the friction heat generated between the first seal member 57 and the second seal member 58 is radiated to the outside through the gap 55.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 4 shows a schematic structure of the entire internal mechanism of the laser copying machine, which is equipped with a developing device using a bearing device according to an embodiment of the present invention.

In the figure, reference numeral 10 is a copying machine main body, and reference numeral 11 is an original reading device provided on the upper portion of the copying machine main body 10.

However, when performing copying using this laser copying machine, the original 13 is set on the original placing surface 12,
Press the start button (not shown). Then, the image information of the document 13 is read by the reading element 17 using the irradiation lamp 14, the mirror 15, and the lens 16, and the read content is sent to the image processing device 18.

On the other hand, the photosensitive member 20 is rotationally driven in the direction of arrow A, at which time the surface thereof is uniformly charged by the charging device 21, and based on the data from the image processing device 18, the photosensitive member 20 is read by the optical writing device 22. -The light L is irradiated to form an electrostatic latent image on the photoconductor 20. This latent image is generated by the developing device 23.
Visualized by the developer as it passes through the location. And
This visible image is transferred by the transfer device 25 onto the paper P sent by the registration roller pair 24 at a timing. After the transfer, the sheet P is conveyed by the conveying belt 26 to the fixing device 27, where heat and pressure are applied to fix the visible image on the sheet P. After fixing, the paper P is sent out from the fixing device 27, discharged onto the paper discharge tray 28, and stacked.

After the transfer of the visible image, the photoconductor 20 is cleaned with a brush roller 30 of a cleaning device 29 to remove the residual developer.
The static elimination lamp 31 eliminates the residual electric charges to prepare for the next use.

By the way, the above-mentioned developing device 23 is constructed in detail as shown in FIG. Reference numeral 35 in the drawing is a developing case. The developing case 35 has a box shape and is provided with a developing window 36 facing the photoconductor 20 side. In the developing case 35, a pair of upper and lower developing rollers 37 and 38 are rotatably provided in contact with the photoconductor 20 through a developing window 36, and a developer transport roller is provided on the right side of the developing rollers 37 and 38 in the figure. 39, a stirring roller 40, and a mixing roller 41 are arranged in this order and are rotatably provided.

During development, the mixing roller 41 is rotated clockwise to mix the developer and the stirring roller 4
0, the agitating roller 40 is rotated counterclockwise to agitate the developer to supply it to the developer conveying roller 39, and the developer conveying roller 39 is rotated clockwise to develop the developer. Attaches to 37 and 38. Then, the developer on the developing rollers 37 and 38 is electrostatically attached to the surface of the photoconductor 20 to perform development.

The developing case 35 of the developing device 23 described above passes through the center of each roller shaft of the developing roller 37, the developer conveying roller 39, the stirring roller 40, and the mixing roller 41, as shown in the drawing, and is shown by X in the drawing. The upper case 44 and the lower case 45 are divided into upper and lower parts by X-ray. The upper case 44 and the lower case 45 are projected outwardly on the front and rear side plates in the drawing to project outwardly as shown in FIG.
A plurality of 5b are provided.

Then, the upper case 44 and the lower case 45 are vertically overlapped with each other along the line X--X in FIG. 3, and as shown in FIG. A plurality of mounting holes 50 are formed along the mating surface 48.

Of the plurality of mounting holes 50 ..., The roller shaft 53 of the developer carrying roller 39 is mounted 1
As shown in FIGS. 1 and 2, a bearing 49 is inserted in each of the mounting holes 50.

The bearing 49 is made of plastic and comprises an outer cylinder portion 49a, an inner cylinder portion 49b and a rib portion 49c. The outer tubular portion 49a is formed into a cylindrical shape that fits into the mounting hole 50, and has a flange portion 49d at its outer end. The inner tubular portion 49b is formed concentrically with the outer tubular portion 49a, and a bearing hole 49e is provided at the center. Four rib portions 49c are provided in the diametrical direction orthogonal to each other, and connect the outer tubular portion 49a and the inner tubular portion 49b.

When the upper case 44 and the lower case 45 are overlapped with each other, the outer cylindrical portion 49a put in the mounting hole 50 is held by being sandwiched between the upper case 44 and the lower case 45, and outside the mounting hole 50. Collar 49d on the hole edge
Are engaged.

The bearing hole 49e of the bearing 49 is rotatably provided through the roller shaft 53 of the developer carrying roller 39. The roller shaft 53 has a bearing 49.
The end of the roller shaft 53 is projected outward, and the washer 54 is attached to the circumferential groove of the end so that the movement of the roller shaft 53 inward in the axial direction is restricted.

Although not shown, the roller shaft on the other end side of the developer carrying roller 39 is also supported by the developing case 35 via a bearing similar to the bearing 49 described above.

However, when the developing device 23 is driven, the frictional heat generated between the roller shaft 53 of the developer carrying roller 39 and the bearing 49 is radiated to the outside through the gap 55 between the rib portions 49c. Therefore, it is possible to reduce the temperature rise of the bearing 49 and prevent the wear of the bearing hole 49e from accelerating due to frictional heat.

In the illustrated embodiment described above, the rib portion 4
Four 9c were provided in the diametrical direction orthogonal to each other. However, the present invention is not limited to this, and as shown in FIGS. 5 and 6, for example, one rib portion 49c may be provided in the radial direction. With this configuration, since the inner tubular portion 49b is supported by the one rib portion 49c, the inner tubular portion 49b is deformed by the force that tightens the outer tubular portion 49a even if the bearing 49 is mounted in the mounting hole 50 at any rotation position. Therefore, it is possible to prevent the bearing hole 49d from being deformed, prevent the rotation load of the roller shaft 53 from occurring, and normally maintain the bearing function of the bearing 49.

Further, the configuration shown in FIGS. 7 and 8 may be adopted. Reference numeral 50a in the drawing is a positioning unit. The positioning portion 50a is formed by cutting out the hole edge of the mounting hole 50. On the other hand, the bearing 49 is provided with two rib portions 49c in the diametrical direction, and the collar portion 49 corresponding to the rib portion 49c.
A convex portion 49f is provided inside d. And the upper case 44
When the lower case 45 is overlapped with the positioning case 50a
Put the convex portion 49f in the upper case 44 and the lower case 4
5 along the direction orthogonal to the stacking direction of the ribs 49
c is provided.

With this arrangement, the positioning portion 50a allows the ribs 49c to have the same direction as the upper case 44 and the lower case 45 in the direction perpendicular to the stacking direction.
Since the inner tubular portion 49b is supported by the two rib portions 49c, the inner tubular portion 49b is not deformed by the tightening force acting on the outer tubular portion 49a and the bearing hole 49e is not deformed, and the support strength of the inner tubular portion 49b is enhanced. be able to.

Further, in the above-described embodiment, the outer cylinder portion 49
The inner diameter of a and the outer diameter of the inner tubular portion 49b were the same. But,
As shown in FIG. 9, a taper surface 49g that gradually increases from the inside to the outside may be formed on the outer circumference of the inner tubular portion 49b.

With this arrangement, for example, when oil is applied to the bearing 49, the oil introduced through the void 55 flows inward along the tapered surface 49g, so that the desired portion can be surely and easily oiled.

Further, as shown in FIG. 10, an outer cylinder portion 49a.
A configuration may be adopted in which the tapered surface 49h that gradually increases from the inside to the outside is formed on the inner circumference of.

In this way, the developer that has entered the bearing 49 slides on the tapered surface 49h and falls to the outside.
It is possible to prevent it from staying in the bearing 49 and being melted and solidified by heat.

Although not shown, a filter member or the like for preventing the developer from leaking from the gap 55 may be provided in the bearing 49. Further, in order to prevent the developer from leaking from the void 55, the configuration shown in FIG. 11 may be adopted. Reference numeral 57 in the drawing is a first seal member. The first seal member 5
7 is a thin circular plate having a central hole 57a, through which the roller shaft 53 is loosely inserted, and the outer peripheral edge outer side is provided in close contact with the inner end of the outer cylindrical portion 49a. The roller shaft 53
The second seal member 58 is press-fitted and attached on the top. The second seal member 58 is made of a rubber material, and the peripheral edge of the seal portion 58a is elastically pressed against the inside of the first seal member 57.

The first seal member 57 and the second seal member 58 block the communication between the bearing 49 and the developing case 35 to prevent the developer from leaking from the gap 55.

When the roller shaft 53 is driven to rotate, however, the friction heat generated between the first seal member 57 and the second seal member 58 is radiated to the outside through the gap 55, so that the first seal member 57 and the second seal member are sealed. The wear of the member 58 can be prevented from being accelerated by frictional heat.

In the illustrated embodiment described above, the roller shaft 53 of the developer carrying roller 39 is supported by the bearing. However, although not shown, the same can be applied to the case where each roller shaft of the developing roller 37, the stirring roller 40, and the mixing roller 41 is bearing.

In the illustrated embodiment described above, an example in which a rotary shaft such as the roller shaft 53 is borne is shown. However, although not shown, the present invention can be similarly applied to the case of bearing the sliding shaft.

[0046]

As described above, according to the present invention, the outer cylindrical portion of the bearing is fitted into the mounting hole of the supporting member, and the shaft is supported through the bearing hole of the inner cylindrical portion supported by the ribs in the gap. The frictional heat generated between the bearing and the shaft can be diffused through the air gap to reduce the temperature rise of the bearing and prevent the frictional heat from accelerating the wear of the bearing hole.

According to the second aspect of the present invention, since the inner tubular portion is supported by the one rib portion, even if the outer tubular portion is fitted into the mounting hole at any rotational position, the inner tubular portion is strongly tightened with a strong force. It is possible to prevent the bearing portion from being deformed by deforming the tubular portion, prevent the generation of a rotational load on the shaft, and maintain the bearing function normally.

According to the third aspect of the present invention, the direction of the rib portion is the same as the direction orthogonal to the direction in which the upper case and the lower case are overlapped by the positioning portion, and the two rib portions support the inner cylindrical portion. Therefore, it is possible to enhance the support strength of the inner tubular portion without deforming the bearing hole by deforming the inner tubular portion by the tightening force acting on the outer tubular portion.

According to the fourth aspect of the present invention, for example, when lubricating the bearing, the oil introduced through the gap flows inward along the tapered surface, so that the desired portion can be reliably and easily lubricated. You can

According to the fifth aspect of the present invention, for example, when the developer enters the bearing, the developer slides on the tapered surface and moves to the outside. It can be prevented from being melted and solidified by heat.

According to the sixth aspect, frictional heat generated between the first seal member and the second seal member is dissipated to the outside through the gap when the shaft is driven to rotate, so that the seal members are not worn. It is possible to reduce hastening due to frictional heat.

[Brief description of drawings]

FIG. 1 is a side view showing a bearing device according to an embodiment of the present invention when viewed from the axial direction of its roller shaft.

FIG. 2 is a sectional view taken along the line CC in FIG.

FIG. 3 is a schematic configuration diagram of a developing device using the bearing device.

FIG. 4 is a schematic configuration diagram of an entire internal mechanism of a laser copying machine including the developing device.

FIG. 5 is a side view showing a bearing device according to another embodiment of the present invention as viewed from the axial direction of the roller shaft thereof.

6 is a cross-sectional view taken along the line DD in FIG.

FIG. 7 is a side view showing a bearing device according to still another embodiment of the present invention as viewed from the axial direction of its roller shaft.

8 is a cross-sectional view taken along the line EE in FIG.

FIG. 9 is a sectional view taken along the roller shaft of a bearing device according to still another embodiment of the present invention.

FIG. 10 is a sectional view taken along the roller shaft of a bearing device according to still another embodiment of the present invention.

FIG. 11 is a sectional view taken along the roller shaft of a bearing device according to still another embodiment of the present invention.

[Explanation of symbols]

 35 developing case (supporting member) 44 upper case 45 lower case 49 bearing 49a outer cylinder part 49b inner cylinder part 49c rib part 49e bearing hole 49g taper surface 49h taper surface 50 mounting hole 50a positioning part

Claims (6)

[Claims] 1. A bearing device in which a bearing is fitted in a mounting hole of a support member and a shaft is supported through the bearing hole of the bearing, wherein the bearing is fitted in the mounting hole and clamped and held by the support member. A bearing device comprising: a portion, an inner cylindrical portion having the bearing hole, and a rib portion connecting them. 2. The rib portion is one.
Bearing device according to. 3. The mounting hole is formed by stacking two constituent parts constituting the support member, and the bearing fitted in the mounting hole is held by being sandwiched by the two constituent parts. The bearing device according to claim 1, wherein the support member is provided with a positioning portion that determines a rotational position of the bearing, and the rib portion is provided in a diametrical direction in a direction orthogonal to a direction in which the two constituent portions are overlapped with each other. apparatus. 4. The tapered surface, which gradually increases from the inner side to the outer side, is formed on the outer circumference of the inner cylindrical portion.
Bearing device according to. 5. The bearing device according to claim 1, which is used in a developing device, wherein a taper surface is formed on an inner circumference of the outer cylinder portion, the taper surface gradually increasing from the inner side to the outer side. 6. The bearing device according to claim 1, wherein the bearing device is used in a developing device, the outer peripheral edge outer side of the first seal member is brought into close contact with the inner end of the outer cylindrical portion, and the shaft is passed through the center of the outer periphery of the first seal member. A bearing device comprising a second seal member press-fitted and the seal portion of the second seal member elastically pressed against the inside of the first seal member.