KR100561426B1 - Bearing structure and fusing device for image forming apparatus employing the same - Google Patents

Abstract

Disclosed are a bearing structure having a structure in which wear between a roller and a bearing can be reduced in a situation in which pressure is applied, and a fixing device for an image forming apparatus employing the same.

The disclosed bearing structure is installed between the frame and the rotating shaft to rotatably support the rotating shaft with respect to the frame, the bearing body having a coupling part to which the rotating shaft is rotatably coupled, and to be installed on at least a portion of the inside of the coupling part. It characterized in that it comprises a rolling support means in rolling contact with the rotation axis.

In addition, the disclosed image forming apparatus fixing apparatus includes a fixing roller having a heater; A pressure roller disposed to face the fixing roller to press the paper discharged together with the fixing roller; A bearing structure rotatably supporting the fixing roller and the pressure roller with respect to the frame, the bearing structure including a bearing body having a coupling portion and rolling support means installed in at least one portion of the coupling portion and rollingly coupled to the roller; It is characterized by including.

Description

Bearing structure and fusing device for image forming apparatus employing the same

1 is a schematic cross-sectional view showing a conventional fixing device for an image forming apparatus.

2 is a schematic view for explaining the operation of a fixing apparatus for a conventional image forming apparatus.

Figure 3 is an exploded perspective view showing a bearing structure according to an embodiment of the present invention.

4 is a schematic view showing an extract of the main portion of FIG.

Figure 5 is an exploded perspective view showing a bearing structure according to another embodiment of the present invention.

6 is a schematic cross-sectional view showing a fixing apparatus for an image forming apparatus according to an embodiment of the present invention.

7 is a schematic view for explaining the operation of FIG.

Explanation of symbols on the main parts of the drawings

41, 101 ... frame 43 ... space

45 ... rotating shafts 50, 70, 130 ...

51, 71, 131 Bearing body 53

54 Mounting groove 56

57 ... elastic member 60, 80 ... rolling support means

61, 81 ... bushing 63, 83 ... guide shaft

65, 85, 145 support belt 87 housing

111 ... Fixing Roller 121 ... Pressure Roller

The present invention relates to a bearing structure for rotatably supporting a roller and a fixing apparatus for an image forming apparatus employing the roller, and more particularly, to a bearing structure having a structure in which wear between the roller and the bearing can be reduced in a pressure applied situation. A structure and a fixing apparatus for an image forming apparatus employing the same.

Generally, a bearing structure is employed to rotatably install the roller with respect to the fixed frame. That is, the bearing structure is provided between each of both sides of the roller shaft and the frame, and rotatably supports the roller.

Examples of this bearing structure include a ball bearing rotatably supporting a roller through rotation of a ball interposed between an inner ring and an outer ring, and a sliding bearing made of a plastic material rotatably supporting by a slip. Among these, ball bearings are superior to sliding bearings in terms of performance. However, the ball bearings have a disadvantage in that the structure is complicated and the assembly costs are high and the price is very expensive. Therefore, slip bearings which are easy to mass-produce and inexpensive as bearing structures are widely used.

In general, an electrophotographic image forming apparatus scans light on a photosensitive medium charged to a predetermined potential to form an electrostatic latent image, develops the toner of a predetermined color, transfers and fixes it on paper, and prints the image. This image forming apparatus is provided with a fixing apparatus on a printing path, in order to fix the transferred image on paper.

1 and 2, a conventional fixing apparatus for an image forming apparatus includes a frame 1, a hollow fixing roller 11 that is rotatably supported by the frame 1, and this fixing roller 11 ) Rotatably installed on the frame 1 by pressing a heater 15 interposed therein and heating the surface of the fixing roller 11 and a printing paper P passing together with the fixing roller 11. The pressure roller 21 and the bearing structure 30 for rotatably supporting each of the fixing roller 11 and the pressure roller 21.

The bearing structure 30 includes a sliding bearing 31 installed on the frame 1 and an elastic member 35 for elastically supporting the sliding bearing 31. The sliding bearing 31 is made of a plastic material, and has a bearing groove 33 into which the rollers 11 and 21 are rotatably fitted. At this time, a clearance is formed between the inner surface of the bearing groove 33 and the outer surface of the rollers 11 and 21 fitted therein, and fluid is injected into the rollers 11 and 21 to rotate the rollers 11 and 21. Guide the sliding. The elastic member 35 elastically supports the sliding bearing 31 in a predetermined direction so that the pressure roller 21 presses the fixing roller 11.

As described above, in the case where the fixing roller 11 and the pressing roller 21 are rotatably supported in a state in which the pressing force is applied in a predetermined direction, a predetermined area of the inner surface of the bearing groove 33, that is, opposite to the direction in which the pressing force is applied. The region A located in the direction has a narrower gap than other regions, and is directly in contact with the rollers 11 and 21 with a large load.

This increase in load may cause wear of the sliding bearing 31 and problems of system malfunction and shutdown. In addition, the foreign matter (C) generated by the wear remaining in the bearing groove 33, may cause a problem that the bearing does not operate normally.

On the other hand, it may be considered to employ a ball bearing for the above fixing device, but because the structure of the ball bearing is large, and the mold bearing must be used inside the ball bearing, the structure is complicated and the assembly labor is high, and the manufacturing The disadvantage is that the price is higher than the sliding bearing.

In addition, ball bearings are made of a hard metal material compared to sliding bearings made of plastic. Therefore, the shape of the ball bearing is changed even when the fixing roller is heated to an abnormal temperature such that the plastic material is deformed by the heater installed therein. I never do that. On the other hand, the general fixing device adopts a structure that employs a fuse that blocks the heating of the heater during non-ideal heating depending on the degree of deformation of the bearing during heating at high heat. Therefore, in the case of employing the above-described ball bearing for the fixing device of such a structure, the bearing is not deformed even at non-ideal high temperature, so there is a high possibility that a fire may occur, and thus there is a disadvantage in that the fuse employing structure cannot be obtained.

Accordingly, the present invention has been made in view of the above-described problems, and an object of the present invention is to provide a bearing structure having a structure capable of preventing abrasion during operation while employing a sliding bearing and a fixing apparatus for an image forming apparatus employing the same. There is this.

In order to achieve the above object, the present invention is a bearing structure installed between the frame and the rotating shaft, rotatably supporting the rotating shaft with respect to the frame, the bearing body having a coupling portion rotatably coupled to the rotating shaft; It is installed on at least a portion of the inside of the coupling portion, rolling support means in contact with the rotary shaft; characterized in that it comprises a.

In addition, the fixing apparatus for an image forming apparatus according to the present invention includes a fixing roller having a heater; A pressure roller disposed to face the fixing roller to press the paper discharged together with the fixing roller; And a bearing structure rotatably supporting the fixing roller and the pressure roller with respect to the frame, wherein the bearing structure includes: a bearing body having a coupling part to which at least one of the fixing roller and the pressure roller is rotatably coupled; ; It is installed on at least a portion of the inside of the coupling portion, rolling support means in contact with the roller coupled to the; characterized in that it comprises a.

Hereinafter, a bearing structure and a fixing apparatus for an image forming apparatus employing the same according to a preferred embodiment of the present invention with reference to the accompanying drawings will be described in detail.

3 and 4, the bearing structure 50 according to an embodiment of the present invention is installed between the frame 41 and the rotation shaft 45, it is possible to rotate the rotation shaft 45 with respect to the frame 41 Support. The bearing structure 50 has a bearing body 51 having a coupling portion 53 to which the rotating shaft 45 is rotatably coupled, and a rolling support provided in the coupling portion 53 and rolling-contacted to the rotating shaft 45. Means 60.

The frame 41 is formed with a space portion 43 in which the bearing structure 50 of the present invention is installed. The bearing structure 50 has guide grooves 52 formed on both sides thereof so as to be slidingly coupled to the space portion 43. Therefore, by coupling the guide groove 52 to the frame 41 on both sides of the space 43, it is possible to install the bearing structure 50 on the frame 41. Here, the coupling of the bearing structure 50 to the frame 41 is merely exemplary, and various modifications are possible.

In addition, the bearing structure 50 according to an embodiment of the present invention preferably further includes an elastic member 57 interposed between the bearing body 51 and the frame 41. The elastic member 57 elastically presses the bearing main body 51 against the frame 41 in a predetermined direction. Therefore, when supporting the rotating shaft 45 rotated while applying pressure in a predetermined direction, it is possible to apply a constant pressing force by the elastic bias.

The bearing structure 50 is a kind of sliding bearing, and is made of a plastic material resistant to friction and heat caused by rotational support. That is, the rotation shaft 45 is coupled to the coupling portion 53 formed in the bearing body 51 so as to be freely rotatable by sliding.

Here, a play is formed between the inner wall of the coupling portion 53 and the rotation shaft 45. It is preferable that a fluid is injected into this clearance so as to help the free rotation of the rotating shaft 45. On the other hand, in a situation where the pressing force is applied to the rotary shaft 45 in a predetermined direction, the play is eccentrically formed in one direction, so that the play of the specific portion is narrowed.

The rolling support means 60 is installed at the portion where the clearance is narrowed as described above, and is in rolling contact with the rotation shaft 45.

In order to provide the rolling support means 60, an installation groove 54 is drawn in at least one region of the coupling portion 53, for example, a portion where the clearance is narrowed. Here, the bearing body 51 has sidewalls 55 formed on both sides of the installation grooves 54 to have a predetermined thickness, and the side walls 55 are formed with a plurality of coupling grooves 56.

The rolling support means 60 is provided to surround a plurality of bushings 61, a plurality of guide shafts 63 freely rotatably coupled to each of the bushings 61, and a plurality of guide shafts 63. And a support belt 65.

Each of the plurality of bushings 61 is installed to be coupled to the coupling part 53, that is, the side wall 55, and rotatably supports the guide shaft 63. Each of the plurality of guide shafts 63 is disposed at a predetermined position in the coupling portion 53, and both ends thereof are rotatably installed in the bushing 61. Therefore, when the external force is applied, it is freely rotated in the coupling groove (53).

The support belt 65 is installed to completely surround the plurality of guide shafts 63. That is, as shown in FIG. 4 by coupling the guide shaft 63 to the bushing 61 through the support belt 65 with the support belt 65 positioned in the installation groove 54. It may have the same configuration.

In this way, the support belt 65 is coupled to the surface 65a exposed in the coupling portion 53 is in direct contact with the rotary shaft 45. Therefore, the support belt 65 is driven in the rotational direction of the rotational shaft 45 in conjunction with the rotational direction of the rotational shaft (45). At this time, since the guide shaft 63 is rotatably installed with respect to the bushing 61, the guide shaft 63 helps the support belt 65 to travel.

Referring to FIG. 5, a bearing structure according to another embodiment of the present invention is installed between the frame 41 and the rotation shaft 45 to rotatably support the rotation shaft 45 with respect to the frame 41. The bearing structure 70 has a bearing body 71 having a coupling portion 73 to which the rotary shaft 45 is rotatably coupled, and a rolling support provided in the coupling portion 73 and rolling contact with the rotary shaft 45. Means 80.

The bearing structure 70 according to the present embodiment is compared with the bearing structure 50 according to the embodiment described with reference to FIGS. 3 and 4, and the rolling support means 80 having a separate and independent configuration. It is characterized in that to provide, and to install it in the coupling portion (73). Therefore, the above-described differences will be mainly described, and detailed descriptions of the remaining components will be omitted.

To this end, the bearing body 70 includes a space portion 74 formed in at least one region within the coupling portion 73. The space portion 74 is provided with a rolling support means 80 formed integrally.

The rolling support means 80 includes a housing 87 having an internal space formed therein, a plurality of bushings 81, a guide shaft 83, and a support belt 85.

The housing 87 is coupled to the space portion 74 while the bushing 81, the guide shaft 83, and the support belt 85 are assembled therein. Here, the housing 87 may be installed in the space portion 74 through bonding using an adhesive, screwing, hooking, and the like. As an example of coupling the housing 87 to the space portion 74, FIG. 5 discloses a guide groove 74a and a guide rail 87a formed in each of the mutually opposing portions of the space portion 74 and the housing 87. It is.

The housing 87 has a side wall 88 provided around an internal space formed therein, and the side wall 88 is formed with a plurality of coupling grooves 89. The bushing 81 is coupled to each of the coupling grooves 89. The guide shaft 83 is freely rotatably coupled to each of the bushings 81 and guides the rotational movement of the support belt 85.

The support belt 85 coupled as described above has the surface exposed in the coupling portion 73 in direct contact with the rotation shaft 45, interlocked with the rotation direction of the rotation shaft 45, and the rotation direction of the rotation shaft 45. Is driven.

6 and 7, a fixing apparatus for an image forming apparatus according to an exemplary embodiment of the present invention includes a fixing roller 111, a pressure roller 121 contacting and rotating the fixing roller 111, and a frame 101. It comprises a bearing structure 130 for rotatably supporting the fixing roller 111 and the pressure roller 121 with respect to.

The fixing roller 111 is rotatably installed in the frame 101 through the bearing structure 130. The heater 115 is built in the fixing roller 111. Therefore, the image transferred to the printing medium P together with the pressure roller 121 is fixed at high temperature and high pressure. Here, since the fixing roller 111 and the pressure roller 121 is driven to rotate while applying a mutual pressure with the print medium (P) therebetween, the bearing structure 130, the fixing roller 111 and the bearing structure 130 ) And the pressing roller 121, the coupling portion located in the direction opposite to the direction in which the pressing force is applied to each other becomes narrower than the other areas.

The bearing structure 130 includes a bearing body 131 having a coupling part 133 to which the fixing roller 111 and the pressure roller 121 are rotatably coupled, and at least a portion of the coupling part 133. It is configured to include a rolling support means 140 which is installed in and coupled to the fixed and pressurized rollers (111, 121) in contact with the rolling. Here, the rolling support means 140 includes a support belt 145 which is in direct contact with the fixing and pressing rollers 111 and 121, and is located in a region where the gap of the coupling part 133 is narrow. It is provided, to help the fixing and pressing rollers 111, 121 rotate smoothly.

Since the bearing structure 130 is substantially the same as the configuration and operation of the bearing structure described above with reference to FIGS. 3 to 5, a detailed description thereof will be omitted.

On the other hand, in the present embodiment, the bearing structure including the above-mentioned rolling support means has been described as an example of supporting both the fixing roller and the pressure roller, but this is only an example, it is also possible to support only one roller.

As described above, the rolling support means 140 is employed in the portion where the gap is narrowed so that the rolling contact means is brought into rolling contact instead of frictional contact in a specific portion, thereby causing friction between the fixing and pressing rollers 111 and 121 and the bearing body 131. Can be reduced.

The bearing structure according to the present invention configured as described above can reduce the wear between the roller and the bearing in a situation in which the pressing force is applied by employing a support belt rotated in conjunction with the rotation of the roller. In addition, in the construction of the bearing structure, when adopting a structure in which the rolling support means is made of a single part independently of the bearing body and then joined, the rolling support means can be easily assembled and installed, thereby reducing the number of assembly operations. have.

In addition, the fixing apparatus for an image forming apparatus employing the bearing structure adopts a sliding bearing whose structure is changed in place of the ball bearing, whereby the problem in the case of employing the ball bearing can be fundamentally prevented. In addition, by providing the rolling support means including the support belt in the bearing body to enable the rolling contact, it is possible to reduce the friction in the portion where the pressing force is large, there is an advantage that foreign matters caused by wear does not occur.

The above embodiments are merely exemplary, and various modifications and equivalent other embodiments are possible to those skilled in the art. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the invention described in the claims below.

Claims (14)

delete In the bearing structure provided between the frame and the rotating shaft, rotatably supporting the rotating shaft relative to the frame, A bearing body having a coupling part to which the rotation shaft is rotatably coupled and an installation groove formed in at least one region of the coupling part; Rolling support means having a plurality of guide shafts rotatably coupled to the installation groove and the support belt is installed so as to surround the plurality of guide shafts in direct contact with the rotating shaft; Bearing structure. The method of claim 2, The rolling support means, And a plurality of bushings positioned in the installation groove to support the guide shaft. In the bearing structure provided between the frame and the rotating shaft, rotatably supporting the rotating shaft relative to the frame, A bearing body having a coupling part to which the rotating shaft is rotatably coupled; A housing having a plurality of engaging grooves formed therein and having a plurality of coupling grooves formed on the sidewalls, a plurality of guide shafts freely coupled to the coupling grooves, and installed to surround the plurality of guide shafts. Rolling support means having a support belt in contact with the rolling; bearing structure comprising a. The method of claim 4, wherein The rolling support means, And a plurality of bushings positioned in the installation groove to support the guide shaft. The method of claim 4, wherein The bearing body includes a space portion formed in at least one region in the coupling portion, The rolling support means is a bearing structure, characterized in that coupled to the space portion. The method according to any one of claims 2 to 6, And an elastic member interposed between the frame and the bearing body to elastically press the bearing body in a predetermined direction with respect to the frame. delete A fixing roller with a built-in heater; A pressure roller disposed to face the fixing roller to press the paper discharged together with the fixing roller; And a bearing structure rotatably supporting the fixing roller and the pressure roller with respect to the frame. The bearing structure, A bearing body having a coupling part to which at least one of the fixing roller and the pressure roller is rotatably coupled, and an installation groove formed in at least one region of the coupling part; Rolling support means having a plurality of guide shafts rotatably coupled to the installation groove and the support belt is installed so as to surround the plurality of guide shafts in direct contact with the roller; Fixing apparatus for an image forming apparatus. The method of claim 9, The rolling support means, And a plurality of bushings positioned in the installation groove to support the guide shaft. A fixing roller with a built-in heater; A pressure roller disposed to face the fixing roller to press the paper discharged together with the fixing roller; And a bearing structure rotatably supporting the fixing roller and the pressure roller with respect to the frame. The bearing structure, A bearing body having a coupling part to which at least one of the fixing roller and the pressure roller is rotatably coupled; A housing having a plurality of engaging grooves formed on the sidewalls thereof; Rolling support means having a support belt in contact with the rolling; Fixing device for an image forming apparatus comprising a. The method of claim 11, The rolling support means, And a plurality of bushings positioned in the installation groove to support the guide shaft. The method of claim 11, The bearing body includes a space portion formed in at least one region in the coupling portion, And the rolling support means is coupled to the space part. The method according to any one of claims 9 to 13, And an elastic member interposed between the frame and the bearing body to elastically press the bearing body in a predetermined direction with respect to the frame.

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