JPH05232828A - Fixing device - Google Patents

Abstract

PURPOSE:To simplify an operation by joining replacement parts together in a single unit and providing a means which supports the replacement unit on the frame of a fixing unit in such a manner that it can be freely detached therefrom. CONSTITUTION:The bearing part 2 of a heat roller 1 and the bearing part 4 of a cleaning roller 3 are integrated to compose a bearing 5. The replacement unit 11 is composed, with the heat roller 1, the cleaning roller 3 and a driving gear attached to the bearing 5. The fixing device is provided with the upper frame 61 and the lower frame 62, which can be opened and closed around an opening/closing fulcrum 63. A joint between the upper and lower frames, which is opposite the opening/closing fulcrum 63, is screwed with a fixing screw. By removing this fixing screw, the upper and lower frames 61 and 62 can be opened. The upper and lower frames 61 and 62 are made in the form of a box. The replacement unit 11 is supported on walls at both sides of the upper frame 61 in such a manner that it can be freely detached therefrom. On walls at both sides of the lower frame 62, a pressure roller 9 is supported in such a manner that it can freely rotate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for fixing a toner image in an electrostatic copying machine or the like, and more particularly to an apparatus having means for replacing each part of the fixing apparatus.

[0002]

2. Description of the Related Art An electrostatic copying machine is provided with a fixing device for fixing a toner image transferred on a sheet. The fixing device includes a cylindrical heat roller (upper roller) having a heater inside, and a pressure roller (lower roller) arranged in pressure contact with the heat roller, and between the heat roller and the pressure roller, The toner image is fixed by passing the paper on which the toner image is placed. During this fixing process,
Since toner adheres to the surface of the heat roller, a cleaning roller for wiping the toner is in contact with the heat roller.

[0003]

In order to replace each part of the fixing device constructed as described above, for example, the heat roller, the cleaning roller, the bearing portion, and the gear, each part is sequentially removed, and then a new part is added. It had to be worn one by one, which was very troublesome. Figure 4
FIG. 4A is an assembly drawing of a heat roller, and FIG. 4B is an assembly drawing of a leaning roller. As shown in FIG. 4A, the heat roller 101 is the upper frame 1 of the fixing device.
Supported by 02. When replacing the heat roller 101 and its bearing, the stop ring 103, the gear 104, the bearing 105, the push 106 and the like must be sequentially removed, and then a new heat roller and each component must be mounted in the reverse order. Also, in the cleaning roller, as shown in FIG.
1, after removing the spring 202 and the like, the cleaning roller 203 had to be taken out of the cleaning holder 204, and a new cleaning roller, bearing and the like had to be mounted in the reverse order.

As described above, according to the conventional method, it is necessary to remove each part in order, and then assemble each part sequentially in the reverse order. Therefore, there is a drawback that the parts replacement work is very complicated and time-consuming. It was

SUMMARY OF THE INVENTION An object of the present invention is to provide a fixing device which can easily replace a heat roller, a cleaning roller and peripheral parts thereof.

[0006]

According to the present invention, a heat roller bearing portion and a cleaning roller bearing portion are integrated to form a bearing, and a heat roller, a cleaning roller, a gear and the like are attached to the bearing to form an exchange unit. A means for detachably supporting the replacement unit on the frame of the fixing device is provided.

[0007]

According to the present invention, the bearings of the heat roller and the cleaning roller are integrally formed so that both bearings can be replaced at once, and the replacement unit has both bearings, the heat roller and the cleaning roller. , Gears and the like are mounted, and all the replacement parts can be replaced at once by simply attaching / detaching the replacement unit to / from the frame of the fixing device.

[0008]

Embodiments FIGS. 1A and 1B are a side view and a front view of a replacement unit equipped with a heat roller and a cleaning roller, FIG. 2 is a front view of a fixing device, and FIGS. 3A and 3B. FIG. 6 is a diagram showing a replacement state of a heat roller and a cleaning roller.

The heat roller 1 is formed in a cylindrical shape to accommodate a heater lamp (not shown) inside. An elastic material such as a non-woven fabric is attached to the surface of the cleaning roller 3. The bearing portion 2 of the heat roller 1 and the bearing portion 4 of the cleaning roller 3 are integrated to form a bearing 5. The bearing portion 2 of the heat roller is a slide bearing, and rotatably supports the heat roller 1. The cleaning roller 3 is rotatably supported on the bearing portion 4. The bearing 5 on the front side and the bearing 5'on the back side have substantially the same structure. A drive gear 7 is fitted on the back side of the heat roller 1. The exchange unit 11 is configured with the heat roller 1, the cleaning roller 3, and the drive gear 1a attached to the bearing 5. The replacement unit 11 is attached to the upper frame 61 of the fixing device
When the fixing device is inserted into the main body of the copier with it attached to
The drive gear 7 meshes with the gear of the main body of the copying machine, and the drive force is transmitted to the heat roller 1. Bearing part 2
Notch portions 2a, 2a are formed in parallel on both side surface portions. The notches 2a and 2a are provided for guiding the removal and attachment of the bearing 5, as described later.

The fixing device has an upper frame 61 and a lower frame 62, and the upper and lower frames 61, 62 can be opened and closed at an opening / closing fulcrum 63. A fixing screw 64 is screwed into the seam of the upper and lower frames on the opposite side of the opening / closing fulcrum 63. By removing the fixing screw 64, the upper and lower frames 6
1,62 are opened. The upper and lower frames 61, 62 are formed in a box shape, and the exchange unit 11 is detachably supported on both side walls of the upper frame 61. A pressure roller 9 that is pressed against the heat roller 1 is rotatably supported on both side walls of the lower frame 62. The peeling claw 8 is also detachably supported on the upper frame 61. Peeling nail 8
Assists in peeling the paper from the surface of the heat roller 1.

When the upper frame 61 is rotated in the direction of arrow B around the opening / closing fulcrum 63, the upper and lower frames 61 and 62 are opened as shown in FIG. On the other hand, the main body of the copying machine is also configured to be opened and closed in a shell type, and the fixing device is attached to the lower unit side of the shell type opening / closing mechanism. Then, when the shell type opening / closing mechanism of the copying machine main body is closed (in the direction of arrow A), the pressing piece 10 on the upper unit side of the copying machine main body presses the upper frame 61 of the fixing device, thereby pressing the upper and lower frames 61, 62. To be done. At this time, the heat roller 1 and the pressure roller 9 respectively mounted on the upper and lower frames are simultaneously pressed, so that the heat roller 1 and the pressure roller 9 are pressed against each other.

A structural example of "means for detachably supporting the replacement unit on the frame of the fixing device" will be described. As shown in FIG. 3B, the upper frame 61 of the fixing device is formed with a round hole 61 a having a diameter substantially the same as the diameter of the heat roller 1. A groove 61b parallel to the end side 61c of the upper frame is provided from the round hole 61a. The width C of the groove 61b is almost the same as the width C between the cutouts 2a, 2a, and when the cutouts 2a, 2a are arranged along the wall surface of the groove 61b, FIG. As shown, the replacement unit 11 can be taken out of the upper frame 61 or mounted. If the cutouts 2a, 2a are not along the wall surface of the groove 61b, the replacement unit 11 can rotate about the bearing portion 2 of the heat roller, but cannot be removed from the upper frame 61. Incidentally, the cleaning roller bearing portion 4 of the bearing 5 is provided with a positioning recess 5a on the opposite side thereof.
Is provided. A positioning screw 5b screwed into the upper frame is fitted into the positioning recess 5a, whereby rotation of the bearing 5 (replacement unit 11) is prohibited when the bearing 5 is attached to the upper frame 61.

In the fixing device having the above structure,
The procedure for component replacement will be described. The shell type opening / closing mechanism of the copying machine main body is opened, the fixing screw 64 is removed, and the fixing device is pulled out from the copying machine main body. Then, the upper frame 61 is rotated in the direction of arrow B around the opening / closing fulcrum 63 to move the upper and lower frames 61,
Open 62 (FIG. 3 (A)). Next, set screw 5b
When the replacement unit 11 is removed, the replacement unit 11 can rotate about the bearing portion 2, so that the replacement unit 11 is rotated to the state shown by the broken line in FIG. Thereafter, as shown in FIG. 3B, the replacement unit 11 is taken out of the upper frame 61, the replacement unit 11 itself is replaced with a new one, and the replacement unit 11 is attached in the reverse order.

[0014]

According to the present invention, since the replacement parts are combined into one unit (replacement unit), the parts can be replaced by replacing only one replacement unit, and the operation is simplified. There is.

[Brief description of drawings]

FIG. 1 is a side view and a front view of a replacement unit.

FIG. 2 is a front view of a fixing device.

FIG. 3 is a diagram showing a replacement state of a replacement unit.

FIG. 4 is an assembly diagram showing a conventional procedure for parts replacement.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 heat roller 2 bearing part 3 cleaning roller 4 bearing part 5 bearing 5a positioning recess 5b positioning screw 11 replacement unit 61 upper frame 61a round hole 61b groove 62 lower frame 63 opening / closing fulcrum 64 fixing screw

Claims (1)

[Claims] 1. A heat roller bearing portion and a cleaning roller bearing portion are integrated to form a bearing, and a heat roller, a cleaning roller, a gear and the like are attached to the bearing to form an exchange unit, and the exchange unit is used as a fixing device. A fixing device characterized in that it is provided with means for detachably supporting the frame.