JPH11133781A - Fixing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a leakage of oil in the case of inclining the oil pan by providing a wall section so as to connected to a upper section of the length direction side face of the oil pan, and equipping a packing for preventing the oil leakage oriented from the approximately and part of an opening section of the side section of the oil pan. SOLUTION: The device is allowed to provide the wall section 154 so as to connected to the upper section of the oil pan 150, and to form in a U-shape. The device is allowed to provide the oil packing 163 from the end section of the opening section 155 on the wall section 154 oriented to the oil pan side section, and to provide the oil packing 162 on the bottom section of the oil blade mounting bracket. In such a manner, even in the case of inclining the oil pan 150, the oil accumulated in the recessed section 165 and the oil being present in the oil pan bottom section 166, is prevented from leaking out of the oil pan side section or the oil pan side section in the length direction 157, and accumulated in the oil sink chamber. The device is made possible to prevent the oil leakage out of the oil pan with a simple structure, and to improve the handling performance of the fixing unit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing device, and more particularly, to a structure of an oil pan for supplying oil to oil applying means.

[0002]

2. Description of the Related Art Conventionally, as a heat fixing device used in a color printer or a color copier, two rollers having a heater inside and covered with an elastic layer, that is, a heating roller and a heating roller are used. 2. Description of the Related Art A fixing method in which a contact portion is formed by a pressure roller, and a sheet on which an unfixed toner image is formed is fixed while nipping and conveying the sheet is widely used.

[0003] In this fixing system, an oil applying means is provided to supply a fixed amount of oil to the surface of the heating roller, but the oil from the oil bottle is stored to supply the oil from the oil bottle to the oil applying means. It is common to provide an oil pan for storage.

[0004]

For example, as shown in FIGS. 5, 6, and 9, an oil pan 150 is provided for storing oil from an oil bottle 141, and an oil pan 150 is provided above the oil pan side portion 151. The wall 154 was provided so as to be connected, and was formed in a U-shape.

However, if the oil pan 150 is tilted, such as when the fixing device 19 is removed from the printing apparatus main body 25, the oil accumulated in the concave portion A165 and the oil at the oil pan bottom 166 will not be removed. Leakage has often occurred from the side part A151, the oil pan side part B152, and the oil pan side part longitudinal direction A157.

[0006]

SUMMARY OF THE INVENTION The present invention is characterized in that at least the surface of the heating roller is covered with a silicone rubber, a pressure roller that contacts the heating roller, and that a predetermined amount of oil is applied to the surface of the heating roller. An oil for storing oil from an oil bottle in a fixing device including an oil application unit, an oil bottle that supplies oil to the oil application unit, and a cleaning member that contacts a surface of each of the heating roller and the pressure roller. A pan is provided, a wall is provided so as to be connected to an upper portion of a longitudinal side surface of the oil pan, and the wall is formed to have a U-shape toward the inside of the oil pan, and a part of the wall is provided. Is provided with an opening, and a packing for preventing oil leakage is provided from substantially the end of the opening of the wall toward the side of the oil pan. In the fixing device to be.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

The printing apparatus main body 25 includes developing units 1 to 4, an optical unit 5, a charging unit 8, a photosensitive belt 22, a transfer drum 21, a registration roller 12, a transfer roller 13, a static eliminator 15, a fixing unit 19, and a paper discharge. The rollers 18 and the paper feed cassette 6 are main components.

Next, the operation of the printing apparatus main body 25 will be described.

The charger 8 uniformly charges the photosensitive belt 22 in response to a print start signal from a host (not shown).

The optical unit 5 draws a latent image on the photosensitive belt 22 according to print data sent from the host,
The drawn latent image is developed by any one of the developing units 1 to 4, and the colored particles in the developing unit are applied on the photosensitive belt 22.

The photosensitive belt 22 is rotated by a drive source (not shown), and is placed on the transfer drum 21.
Transfer the colored particles above.

The excess colored particles remaining on the transfer drum 21 are removed by a cleaner a20, and the excess colored particles remaining on the photosensitive belt 22 are removed by a cleaner b23. 8 is charged.

In the case of color printing, this process is repeated three or four times while switching the developing device.

On the transfer drum 21, a visible image is formed by colored particles of a single color or a plurality of colors, and when the desired transfer is completed, or in advance, the paper 2 is transferred from the paper feed cassette 6.
7 is pulled out by the paper feed roller 10 and stands by at the registration roller 12.

At the timing when the position of the visible image formed on the transfer drum 21 coincides with the transfer position on the sheet, the sheet waiting at the registration roller 12 starts to be conveyed again, and At 13 the visible image is transferred to the paper side.

The paper is peeled off from the transfer drum 21 by the static eliminator 15, the colored particles are fixed on the paper by the fixing device 19, and are discharged to the paper discharge tray 28.

FIG. 2 is a sectional view of the fixing device 19 and FIG. 3 is a plan view of the fixing device 19.

The heating roller 127 and the pressure roller 128 are respectively 1.5 mm thick and have a JIS hardness of 40 degrees silicone rubber 127-
2. An elastic roller covered with 2,128-2, having a heater 129 of 400 W and a heater 1 of 300 W
30.

A heating roller 1 is provided around the heating roller 127.
Cleaning roller having heat-resistant fibers coated on a metal core for removing offset toner attached to the surface of 27
131, a temperature sensor 132 for detecting the temperature of the surface of the heating roller 127, and an oil application unit 133 for applying silicone oil stably.

The heating roller 1 is provided on the surface of the pressure roller 128.
A cleaning pad 134 for removing the offset toner transferred from the heater 27 and a fuse 135 for cutting off the current when the heaters 129 and 130 are abnormally heated due to a failure of the temperature sensor 132 or the like. Both sides are protected by covers A146 and B147 for safety.

The oil application unit 133 includes the heating roller 1
27, an oil supply felt 142 for supplying the silicone oil supplied from the oil bottle 141 by capillary action, and an oil blade 1 for regulating the amount of the silicone oil applied to the surface of the heating roller 127 to a certain amount.
43, and is fixed to a heating roller frame 144 holding a heating roller 127, a temperature sensor 132, and the like.

When the heating roller 127 rotates in the direction of the arrow, an oil film of silicon oil is formed on the surface of the heating roller 127, and the releasability between the toner and the surface of the heating roller 127 is improved.

The paper 137 on which the unfixed toner image 136 is formed is conveyed by the entrance guide 138 from the direction of the arrow to the pressure contact portion between the heating roller 127 and the pressure roller 128,
Then, after the toner is fixed on the sheet by the heat and pressure from both rollers, the toner is discharged in the direction of arrow B according to the guides 139 and the discharge guide 140 which also serve as the case of the cleaning roller 131.

Most of the toner fixed at the pressure contact portion between the heating roller 127 and the pressure roller 128 remains on the paper 137, but a small amount of toner (offset toner) is
Attaches to 127.

The offset toner is removed by the cleaning roller 131. However, it is difficult to completely remove the offset toner by the cleaning roller 131, and the offset toner that cannot be completely removed is removed by the heating roller 127 and the pressure roller 128. It accumulates on the surface and reduces the releasability of the roller surface.

If the oil supply felt 142 is contaminated by the offset toner, the oil supply from the oil supply felt 142 to the heating roller 127 becomes insufficient.
The releasability of the roller surface is reduced.

Therefore, it is necessary to supply oil to the oil supply felt 142 from the oil bottle 141 quantitatively.

Conventionally, as shown in FIGS. 5, 6 and 9,
An oil pan 150 is provided for storing oil from the oil bottle 141, and a wall 154 is provided so as to be connected to an upper portion of the oil pan side 151, and is formed in a U-shape.

With this shape, when the oil pan 150 is tilted, for example, when the fixing device 19 is removed from the printing apparatus main body 25, the oil accumulated in the concave portion A165 and the oil at the oil pan bottom 166 are not removed from the oil pan side portion. A151,
Oil pan side part B152, oil pan side part longitudinal direction A
In many cases, leakage from 157 occurred.

On the other hand, as shown in FIGS. 4, 7 and 8, the oil pan side part A151 and the oil pan side part B152 extend from the end of the wall part A154, the wall part B156, the opening part A155 and the opening part B160. Oil packing B16 toward
3. The oil packing C164 was provided, and the oil packing A162 was provided below the oil blade mounting bracket 158.

The oil packing B163, the oil packing C164, and the oil packing A162 are formed in a substantially U shape.

As a result, even when the oil pan 150 is tilted, the oil accumulated in the concave portion A165 and the oil at the oil pan bottom 166 are removed from the oil pan side portion A15.
The oil is stored in the oil storage chamber A159 and the oil storage chamber B161 without leaking from the oil pan side part B152 and the oil pan side part longitudinal direction A157.

[0034]

According to the present invention, oil leakage from the oil pan can be eliminated with a simple structure, and the handling of the fixing device can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a printing apparatus according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a fixing device showing one embodiment of the present invention.

FIG. 3 is a plan view of a fixing device showing one embodiment of the present invention.

FIG. 4 is a sectional view of an oil pan showing one embodiment of the present invention.

FIG. 5 is a sectional view of an oil pan showing a conventional example.

FIG. 6 is a longitudinal sectional view of an oil pan showing a conventional example.

FIG. 7 is a plan view of a main part of an oil pan showing one embodiment of the present invention.

FIG. 8 is a perspective view of a main part of an oil pan showing one embodiment of the present invention.

FIG. 9 is a perspective view of a main part of an oil pan showing a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Developing device 1, 2 ... Developing device 2, 3 ... Developing device 3, 4 ... Developing device 4, 5 ... Optical unit, 6 ... Paper cassette 1, 8 ... Charging device, 10 ... Paper roller 1, 12 ... Registration roller, 1
3: transfer roller, 15: static eliminator, 18: discharge roller, 1
9: fixing device, 20: cleaner a, 21: transfer drum, 2
2: photosensitive belt, 23: cleaner b, 25: printing device main body, 27: paper, 28: discharge tray, 127: heating roller, 127-1, 128-1: cored bar, 127-2, 12
8-2: Silicon rubber, 128: Pressure roller, 129, 1
30 ... heater, 131 ... cleaning roller, 132 ...
Temperature sensor, 133: oil application unit, 134: cleaning pad, 135: fuse, 136: unfixed toner image, 138: entrance guide, 139: guide,
140: paper ejection guide, 141: oil bottle, 142 ...
Oil supply felt, 143 ... oil blade, 144
... Heating roller frame, 145 ... Pressing roller frame,
146: cover A, 147 ... cover B, 148 ... fixed lever, 150 ... oil pan, 151 ... oil pan side A, 152 ... oil pan side B, 153 ... wall inside A, 154 ... wall A, 155 ... Opening A, 156 ... Wall B, 157 ... Oil pan side longitudinal direction A, 158 ... Oil blade mounting bracket, 159 ... Oil reservoir A, 160
... Openings B, 161, Oil reservoir chambers B, 162, Oil packings A, 163, Oil packings B, 164, Oil packings C, 165, Depressions A, 166, Oil pan bottoms.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Katsuyoshi Onose 1-1-1 Higashitagacho, Hitachi City, Ibaraki Prefecture Inside the Taga Headquarters, Hitachi, Ltd.Electrical Equipment Division (72) Inventor Masaru Nakano, Tsuchiura City, Tsuchiura City, Ibaraki Prefecture 502, Machi-cho, Hitachi, Ltd.Mechanical Research Laboratory Co., Ltd.

Claims (3)

[Claims] A heating roller having at least a surface coated with silicone rubber; a pressure roller in contact with the heating roller; oil applying means for applying a predetermined amount of oil to the surface of the heating roller; In a fixing device having an oil bottle for supplying oil and a cleaning member in contact with a surface of each of the heating roller and the pressure roller, an oil pan for storing oil from the oil bottle is provided, and a longitudinal direction of the oil pan is provided. A wall portion is provided so as to be connected to an upper portion of the side surface, the wall portion is formed to have a U-shape toward the inside of the oil pan, and an opening is provided in a part of the wall portion; A packing for preventing oil leakage from substantially the end of the opening toward the side of the oil pan. 2. The fixing device according to claim 1, wherein a packing for preventing oil leakage is provided at a lower part of a mounting bracket of the oil blade on a side in a longitudinal direction of the oil pan. 3. The packing according to claim 1, wherein a packing is provided from a substantially end of the opening of the wall toward a side of the oil pan, and a packing is provided on a side in a longitudinal direction of the oil pan. A fixing device having a U-shape.