JPS6339717Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is based on the fixing and
This invention relates to improvements in drying equipment.

In a liquid development type electrophotographic copying machine, a toner dispersed in a solvent is used as a developer, and a developed image is obtained by adsorbing this to a photoreceptor that can carry an electrostatic latent image. Transfer it to copy paper. Since the toner and the solvent adhere to the transferred copy paper, the solvent must be evaporated during fixing.

By the way, the conventional apparatus for performing the fixing and drying described above does not have sufficient thermal efficiency, so that a sufficient dry state cannot be obtained, and there is a risk that the evaporated solvent may flow into the room.

The present invention aims to eliminate the above-mentioned drawbacks.

Next, the present invention will be explained with reference to illustrated embodiments.

Reference numeral 2 denotes a heating roller whose peripheral surface is coated with Teflon, and is rotated in the direction of arrow A while being heated by the heater 1 . Pressure rollers 5a and 5b are pressed against the heating roller 2 and rotate in the direction of arrow B. Pressure rollers 5a, 5
A heat-resistant endless belt 6 is stretched around b. The endless belt 6 runs as shown by arrow C while being in close contact with the heating roller 2.

Reference numeral 17 denotes a case of the fixing/drying device, which covers and supports each of the rollers 2, 5a, and 5b, and also supports a feed roller 10 and a seal roller 12, each of which has a plurality of rollers fixed to a shaft at regular intervals. are doing. The feed roller 10 and the seal roller 12 rotate in the directions of arrows D and E while elastically contacting a guide plate 17a that constitutes a part of the wall of the case 17.
The guide plate 17a extends inward of the case 17,
It is in contact with the endless belt 6 on the pressure roller 5b. 7 is the entrance of the case 17, and a guide plate 17b is also stretched between it and the pressure roller 5a.

A suction 15 is arranged above the feed roller 10, and a suction fan 16 is arranged above it. A guide wall 9 extending from the end of the suction 15
is suspended between the feed roller 10 and the heating roller 2, and forms an air heating flow path 8 above the heating roller 2. A seal 14 made of an elastic pad is in sliding contact with the case 17 above the seal roller 12. A similar seal 13 is also provided between the case 17 and the endless belt 6.
Note that a guide 11 is provided adjacent to the feed roller 10, is made of piano wire, and faces the guide plate 17a with a slight interval therebetween. Further, 3 is a temperature sensor that detects the peripheral surface temperature of the heating roller 2, and 20 is a temperature controller that controls the heater 1.

The shaft 2a of the heating roller 2 is formed into a cylindrical shape as shown in FIG. 2, and is supported by the case 17 by a bearing 18. A seal 19 is provided between the case 17 and the shaft 2a.

Each of the seals 13, 14, 19 prevents air from entering and exiting therefrom, and the seal roller 12 also prevents air from entering and exiting between it and the guide plate 17a, so that the airflow generated by the operation of the suction fan 16 is prevented. The inlet 7 of the case 17 is the only inflow port, from which it flows as shown by arrow _F1 , passes through the air heating channel 8 as shown by arrow _F2 , and passes through the path of copy paper 4 as shown by arrow _F3 . After flowing along the copy paper between the rollers of the feed roller 10, it reaches the evaporation channel 21, where it is sucked by the suction fan 16 as shown by arrows F ₅ and F ₆ , and is sucked by the suction fan 16 as shown by arrow F ₇ . It follows the path of release as shown. Then, the pressure inside the case 17 becomes lower than the outside pressure.

The copy paper 4 that has undergone the transfer is fed into the case 17 from the entrance 7 with the image side facing upward.
The sheet is then conveyed in the direction of arrow G while being pressed by the endless belt 6 and in close contact with the heating roller 2 . The copy paper 4 is heated and fixed by the heat from the heating roller 2, and the solvent attached thereto is heated. After passing through the heating roller 2, the copy paper 4 is continuously conveyed in the direction of arrow G by the feed roller 10, but it enters from the inlet 7 and is placed above the heating roller 2, that is, at the part of the heating roller 2 that does not contact the copy paper 4. Since the airflow heated in the opposing air heating channel 8 is blown onto the heated copy paper 4 as shown by arrow _F3 ,
The temperature of the air in the vicinity increases, the saturated vapor pressure of the solvent vapor increases, and the relative humidity decreases, promoting the vaporization of the solvent from the copy sheet 4. After passing between the rollers of the feed roller 10, the hot air flows along the copy paper and reaches the evaporation channel 21, where it is also dried. is discharged outside.

The solvent attached to the copy paper 4 is not only heated by the heating roller 2 as described above, but also by the hot air heated by the heat recovered in the air heating channel 8, so that thermal efficiency is improved. However, the effect is closer to heat retention than heating, and the main effect is to accelerate drying by increasing the saturated vapor pressure.

The air containing solvent vapor sucked from the case 17 by the suction fan 16 is exhausted to the outside through a duct (not shown). Since the air pressure inside the case 17 is lower than the outside air pressure, even if there is an incomplete seal, air containing harmful solvent vapor will not escape from there.

As described above, the present invention uses a sealed case so that the copy paper inlet is the only air inlet, and connects an exhaust system to this case, thereby preventing harmful solvent vapor generated inside the case from leaking into the room. It can be discharged without any problem.

Since the air is heated in the air heating channel formed around the heating roller that heats the copy paper, there is no need to separately provide a dedicated heater, and the thermal efficiency can be improved. Moreover, since the heated air flows while coming into contact with the copy paper after it has been heated by the heating roller, it increases the saturated vapor pressure of the solvent vapor, lowers its relative humidity, and promotes evaporation. To efficiently and quickly dry copy paper.

[Brief explanation of drawings]

The figure shows an embodiment of the present invention.
The figure is a longitudinal sectional front view, and FIG. 2 is a longitudinal sectional side view of the bearing portion of the heating roller. 2... Heating roller, 4... Copy paper, 6...
Endless belt, 7...Inlet, 8...Air heating channel, 9...Guide wall, 10...Feed roller, 1
2... Seal roller, 13, 14, 19... Seal, 16... Suction fan, 17... Case, 17
a, 17b...guide plate, 21...evaporation channel.

Claims (1)

[Scope of utility model registration request] a case sealed so that a copy paper inlet becomes an air inlet; an exhaust device connected to the case; a heating roller disposed within the case;
a conveyance device that conveys the copy paper while bringing it into close contact with the heating roller; and an air heating flow that causes air flowing in from the copy paper inlet to flow while contacting a portion of the heating roller other than the copy paper contact area. forming a passage, and the end of the air heating passage is
A feed roller and a seal roller configured to blow hot air toward the copy paper after it has passed through the heating roller, and through which the hot air can pass, are brought into contact with a guide plate that forms part of the wall of the case. An evaporation channel is formed between both rollers, a suction is disposed above the feed roller, and a suction fan is disposed above the suction fan to serve as the exhaust device, so that hot air flows into the evaporation channel while coming into contact with the copy paper. A fixing/drying device for a liquid developing type electrophotographic copying machine, characterized in that it is configured to be discharged outdoors.