JP2003195672A - Liquid coating device and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid coating device which can be miniaturized without causing the failure of the device and which is equipped with a constitution capable of restraining the rise of peripheral atmospheric temperature. <P>SOLUTION: This liquid coating device is used for coating a body to be coated 10C with reservoired liquid, and is provided with a plurality of positions where the liquid is reservoired and further provided with a supply means 16 for setting a liquid flow direction pointing to one direction between a plurality of reservoir parts. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid application device for silicone oil or the like used as an anti-offset liquid and an image forming apparatus using the same, and more specifically to a fixing device used in the image forming apparatus. The present invention relates to an oil supply mechanism for preventing offset.

[0002]

2. Description of the Related Art An image forming apparatus such as a copying machine, a printer or a facsimile machine is provided with a fixing device for thermally fusing and fixing a toner image transferred onto a recording sheet.

In one of the constitutions of the fixing device, a fixing roller having a built-in heat source and a pressure roller capable of interlocking rotation while facing and abutting against this are combined to apply heat and pressure to a toner image. There is a configuration using the method. In the heat roller method, since a roller having a relatively large heat capacity is used, it takes a long time to rise to a predetermined fixing temperature. Therefore, instead of this configuration, a configuration using a belt that can have an extremely small heat capacity has been proposed. In this configuration, the belt is wound around a pair of rollers, one of the rollers is opposed to the pressure roller, and the other of the rollers is provided with a heat source to heat the belt. This configuration not only has the advantage that the temperature rises quickly on the belt and the time required to reach the predetermined fixing temperature can be shortened, but also a part of the stretched surface of the belt is arranged along the peripheral surface of the pressure roller. Therefore, there is an advantage that the nipping width of the recording paper carrying the toner image, that is, the so-called nip width can be increased to increase the heating area for the toner image to improve the fixing efficiency.

On the other hand, the fixing device is provided with a structure for preventing the reverse transfer of the fused toner, that is, the so-called offset, on the member which is in contact with the toner. A configuration is known in which an offset prevention liquid serving as a release agent is applied. As a structure for applying the offset prevention liquid, there is a structure in which a part of the felt is immersed in the offset prevention liquid storage tank and the offset prevention liquid is sucked up and applied using the surface tension of the felt. FIG. 4 is a schematic view showing an example of the fixing device having the above-described configuration. The fixing device shown in the figure is a fixing device using a system using a belt instead of a heat roller system. In FIG. 4, the fixing device A is arranged so as to face the fixing roller C and a belt D wound around a heating roller B having a heat source and a fixing roller C having no heat source, and carries a toner T. A pressure roller E that nips and conveys the sheet S together with the fixing roller C is provided, and an oil applying device F is disposed at a position near the fixing roller C and facing the belt D.

The oil applicator F includes an oil tank F1 containing a release agent such as silicone oil, a suction member F2 such as felt partially immersed in the oil tank F1, and a suction member F2. The leveling roller F3 that is in contact with the other portion and the belt D that is in contact with the leveling roller F3
And a release agent supply roller F4 that is in contact with.

In the oil applying device F, the oil tank F1
The release agent is sucked up from the inside by the capillarity of the suction member F2 and applied to the leveling roller F3. A release agent is applied to the belt D.

The release agent is filled in the oil tank F1 in advance, and it is detected by the consumption detection sensor F5 arranged at the bottom of the oil tank F1 that the amount at which the suction member F2 cannot suck the release agent has been reached. It is like this. When the release agent contained in the oil tank F1 is completely consumed, the consumption detection sensor F5 warns that it is time to replace the oil tank F1. When a large amount of release agent is stored in the oil tank F1 in advance, it is necessary to increase the volume of the oil tank F1, but in this case, a large installation space for the oil tank F1 is required. However, the size of the fixing device is increased.

As a structure for preventing the fixing device from increasing in size, there has been proposed a structure in which an oil tank and a replenishing part for replenishing a release agent are provided separately from the oil tank, and the two are connected by a pipe or the like ( For example, JP-A-6-28075
No. 0, JP-A-6-324592).

In the above publication, a tube is used to connect an oil storage portion in the fixing device and an oil tank provided separately from the oil storage portion, and the oil tank and the oil storage portion are connected to each other during extension of the tube. A configuration in which a pump that circulates the release agent between them is arranged is disclosed.

[0010]

According to the configuration disclosed in the above publication, since the release agent is supplied from the separately provided oil tank to the oil storage portion located inside the fixing device, the oil storage The volume of the part can be reduced.
However, this configuration has the following problems. The oil reservoir and the oil tank are configured to circulate the release agent between the two via a tube communicating with the pump.
In such a configuration, foreign matter that has entered the oil storage portion is likely to be introduced into the pump, which may cause a malfunction of the pump. In other words, the release agent is applied to the fixing member such as the fixing roller that is in contact with the sheet carrying the toner, but the surface of the fixing member has paper dust or dust from the sheet to be contacted. Foreign matter such as the above may adhere over time, and this foreign matter may enter the pump through the tube. As a result, although depending on the model of the pump, increase in frictional resistance and clogging in the rotating portion of the rotor are likely to occur.

On the other hand, the fixing device serves as a heat generating part by using a heat source, and is a part for raising the ambient atmosphere temperature. Therefore, depending on the configuration of the image forming apparatus including the fixing device, the heat generated from the fixing device may adversely affect the operation of the image forming apparatus.

In view of the problems of the above-mentioned conventional fixing device and the image forming apparatus using the same, an object of the present invention is to enable downsizing without causing a problem of the device and to suppress an increase in housewife garden atmosphere temperature. It is an object of the present invention to provide a fixing device and an image forming apparatus having a configuration capable of achieving the above.

[0013]

The invention according to claim 1 is
An apparatus for applying a stored liquid to an object to be coated, wherein the position for storing the liquid is provided at a plurality of positions, and a liquid flow direction directed in one direction is set between the plurality of storage parts. It is characterized in that it is provided with a supply means.

According to a second aspect of the present invention, in addition to the first aspect of the invention, one of the liquid storage portions is provided in the vicinity of the object to be coated, and the other one is separated from the object to be coated. And a liquid supply path in which a pump as a supply means capable of flowing the liquid only toward one of the storage parts is arranged is connected between these storage parts. .

According to the first and second aspects of the invention, the flow direction of the liquid is defined as one direction, and in particular, the direction in which the liquid from the object to be coated does not return to the pump serving as the supply means is specified. It is possible to avoid mixing of foreign matter into the means.

In addition to the invention described in claim 2, the invention described in claim 3 is characterized in that a part of the liquid supply passage is configured as a heat exchange portion.

The invention according to claim 4 is characterized in that, in addition to the invention according to claim 3, a part of the liquid supply passage is configured as a heat exchange portion for lowering the temperature.

According to the third and fourth aspects of the present invention, a part of the liquid supply path functions as a heat exchange section, and therefore the influence of heat generated on the coated object side does not affect the peripheral section.

According to a fifth aspect of the present invention, there is provided an image forming apparatus using the liquid applying apparatus according to any one of the first to fourth aspects, wherein a fixing member for unfixed toner is used as the object to be coated. It is characterized by that.

According to the fifth aspect of the present invention, since the fixing member is used as the object to be coated, the size of the liquid storage portion in the vicinity of the fixing member can be reduced and the liquid does not return from the liquid storage portion. It is possible to prevent foreign matter from entering the pump, which is the liquid supply means, to prevent liquid supply failure, and also to prevent the heat from the fixing member from affecting the peripheral part by the heat exchange part formed in the middle of the supply path. it can.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the embodiments shown in the drawings. FIG. 1 is a schematic view showing an example of an image forming apparatus equipped with a liquid coating apparatus according to an example for explaining an embodiment of the present invention. In the figure, an image forming apparatus 1 is a full-color printer capable of forming not only a single color but also a plurality of color images, and includes a plurality of rollers 2A and 2A.
The belt-shaped photosensitive member 2 is provided around B and 2C.

The photoconductor 2 is adapted to undergo the steps of charging, writing, developing and transferring in the process of moving in the direction of the arrow in the figure. Therefore, in the vicinity of the photoconductor 2, a charging device (not shown), the writing device 3, and cyan, magenta, yellow, and black which are in a complementary color relationship with the color separation color of the electrostatic latent image formed on the photoconductor 2. Developing devices 4M, 4C, 4Y and 4 capable of supplying the same toner
B, primary transfer device 5, cleaning device (not shown)
Are arranged.

A belt is used as the primary transfer device 5, and after the image subjected to the visible image processing by each developing device is superimposed and transferred, the secondary transfer device is applied to the sheet S fed from the paper feeding device 6. 7 is used for batch transfer. The sheet S fed from the sheet feeding device 6 is fed to the secondary transfer device 7 after the registration timing is set by the registration roller 8 arranged in the middle of the conveyance path.
A belt cleaning device 9 is arranged at a position where the belt of the primary transfer device 5 moves after the completion of the secondary transfer. Two
A fixing device 10 for fixing the unfixed toner carried on the sheet is provided at a position where the sheet S, which has been collectively transferred by the next transfer device 7, is moved. The sheet S that has been fixed is discharged onto the discharge tray 12 by the discharge roller 11.

The fixing device 10 is shown in FIG. In FIG. 2, the fixing device 10 includes a heating roller 10A and a fixing roller 10B having the same configuration as that shown in FIG.
The fixing belt 10C that is wound around the further fixing roller 1
0D, the pressure roller 10D, and the liquid application device 11
It has and.

The liquid coating device 11 includes an oil storage portion 11A provided in the vicinity of the fixing belt 10C corresponding to an object to be coated with the release agent, and an image at a position different from the fixing device 10 as shown in FIG. An oil tank 12 is provided in the housing of the main body of the forming apparatus, which serves as a reservoir for the replenishment release agent. Note that, in FIG. 2, reference numerals F2, F3, and F4 indicate a suction member, a leveling roller, and a release agent supply roller having the same functions as those shown in FIG. The oil storage portion 11A constitutes a release agent accommodation space provided in the fixing device 10, and a part of the suction member 13 such as felt is immersed in the release agent accommodated therein.
An opening 11A1 is provided in a part of the upper surface of the oil storage portion 11A, and an end opening of a replenishment pipe 14 described later is arranged in the opening 11A1. A residual amount detection sensor SP capable of detecting the residual amount of the release agent is provided below the oil storage portion 11A.
Are connected to the input unit of the control unit 100 shown in FIG.

The oil tank 12 is a tank provided inside the image forming apparatus at a position different from the fixing device 10, and the oil storage portion 11A is a replenishing pipe 15 forming a liquid supply path as shown in FIG. Has been extended and contacted. The replenishment pipe 15 is a member that constitutes a release agent supply path between a plurality of release agent reservoirs, and as shown in FIG. 3, a pump 16 that serves as a release agent supply means is disposed midway in the extension direction. Has been done. The pump 16 has a flow direction set so that it can be conveyed only to the reservoir 11A containing the release agent in the oil tank 12, and the release agent recirculates from the oil reservoir 11A to the oil tank 12. You can't.

In FIG. 3, the control unit 100 is connected to the above-mentioned remaining amount detection sensor SP on the input side and connected to the pump side on the output side so that the remaining amount of the release agent in the well of the oil storage unit 11 can be controlled. Accordingly, the pump 16 is driven to replenish the release agent.

Since this embodiment has the above-mentioned structure,
The release agent sucked up from the oil storage section 11A by the suction member F2 in the oil storage section 11A is applied to the fixing belt 10C via the leveling roller F3 and the release agent supply roller F4. When the residual amount of the release agent reaches a fixed amount in the oil storage section 11A, the control section 100 drives the pump 16 to move the release agent from the oil tank 12 to the storage section 11A through the supply pipe 15. Is replenished.

Since the pump 16 only causes the release agent from the oil tank 12 to flow toward the oil storage section 11A, the release agent from the oil storage section 11A is pumped by the pump 16.
Never pass through. As a result, the fixing belt 10
Even if the foreign matter adhered to the fixing belt 10C with respect to the member supplying the release agent to C is mixed in the oil reservoir 11A, it does not enter the pump 16. As a result, even if there is a substance that deteriorates the supply performance of the pump depending on the foreign matter, it is possible to prevent the deterioration of the performance of the pump 16 in advance.

According to this embodiment, in order to reduce the size of the release agent storage section installed in the fixing device 10, a storage section as a release agent supply section is provided at a position different from the fixing apparatus. If a supply means such as a pump is connected between the two storage parts by a pipe disposed in the middle of the storage means, the release agent from the fixing device side will not enter the supply means, so the replenishment function of the release agent is maintained normally. It becomes possible.

Next, another embodiment of the present invention will be described. In FIG. 3, the pipe 15 laid between the oil storage portion 11A and the oil tank 12 is not laid in a straight line or a curved line between both positions,
Along with that, the heat exchange section 15A is formed by being folded back into a plurality of stages. The heat exchange 15A is wandered to a position where temperature rise is not desirable inside the image forming apparatus.
The position where the temperature rise is not preferable in the image forming apparatus is a place where parts subject to temperature restrictions are used for quality assurance or a position where a developing device using toner whose quality is significantly changed due to temperature is arranged. Is the target.

Since the present embodiment is constructed as described above,
The release agent supplied from the oil tank 12 toward the oil storage portion 11A can receive heat at a portion where the ambient atmospheric temperature rises due to the laid state of the pipe. As a result, the ambient temperature around the heat exchange section 15A in which the supply pipe 15 is wandered can be lowered. Such a temperature lowering effect is effectively obtained because the supply direction of the release agent is defined in one direction from the oil tank 12 to the oil storage portion 11A. That is, since the release agent is not returned to the oil tank 12 from the fixing device side, the temperature of the release agent flowing in the replenishment pipe 15 does not rise unlike the case where the release agent returns from the fixing device side. Therefore, a large thermal gradient with respect to the ambient atmosphere temperature can be taken, and the ambient atmosphere temperature can be easily lowered.

[0033]

According to the inventions of claims 1 and 2,
Since the liquid is supplied only in one direction without circulating between the liquid flow parts provided at a plurality of locations, it is possible to supply the liquid even if the size of the storage part located near the object to be coated is reduced. In particular, in the invention according to claim 2, a pump is provided as a supply means for setting the flow direction of the liquid only to one of the storage parts located in the vicinity of the object to be coated, between the storage parts. Since it is arranged, liquid from the object to be coated does not enter, and foreign matter from one of the reservoirs is prevented from entering the pump to prevent malfunction of the device related to liquid supply. Is possible.

According to the third and fourth aspects of the invention, a part of the liquid supply passage is used as the heat exchange section, and particularly in the fourth aspect of the invention, the heat exchange section is used for lowering the ambient atmospheric temperature. Therefore, it becomes possible to prevent a malfunction of the device caused by a rise in ambient temperature.

According to the fifth aspect of the invention, since the fixing member for the unfixed toner is used as the object to be coated, the foreign matter adhering to the object to be coated when the unfixed toner is brought into contact with the supply means. In addition, since the heat generated in the fixing member can be prevented from affecting the peripheral portion, the size of the storage portion located in the vicinity of the fixing member can be reduced, and the malfunction of the device can be ensured with the downsizing of the device. Can be prevented.

[Brief description of drawings]

FIG. 1 is a schematic diagram for explaining a configuration of an image forming apparatus using a liquid coating apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic view of a part of which is a cross section for explaining the configuration of a main part of the liquid application device shown in FIG.

FIG. 3 is a schematic view with a part in section for explaining a supply structure used in the liquid coating apparatus shown in FIG.

FIG. 4 is a schematic diagram showing a fixing device for explaining a conventional configuration of a liquid application device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 10 Fixing apparatus 10C Fixing belt 11 corresponding to an object to be coated 11 Liquid applying apparatus 11A Oil storage section 12 which is one of a plurality of storage sections Oil tank 15 which is another one of a plurality of storage sections Replenishment pipe 16 corresponding to the liquid supply path between the reservoirs Pump corresponding to the liquid supply means

Claims (5)

[Claims] 1. A device for applying a stored liquid to an object to be coated, wherein the position for storing the liquid is provided at a plurality of positions, and the liquid is directed in one direction between the plurality of storage parts. A liquid applying device, characterized in that a supply means for setting a liquid flow direction is provided. 2. The liquid applying apparatus according to claim 1, wherein one of the liquid storage parts is provided near the object to be coated, and the other one is provided at a position apart from the object to be coated, A liquid application device is characterized in that a liquid supply path in which a pump as a supply means capable of flowing a liquid only toward one of the storage parts is arranged is connected between these storage parts. 3. The liquid coating apparatus according to claim 2, wherein a part of the liquid supply passage is configured as a heat exchange section. 4. The liquid application apparatus according to claim 3, wherein a part of the liquid supply path is configured as a heat exchange section for lowering the temperature. 5. An image forming apparatus using the liquid applying apparatus according to claim 1, wherein an unfixed toner fixing member is used as the object to be applied. Forming equipment.