KR100327206B1 - Fusing apparatus of printer - Google Patents

Abstract

Disclosed is a fixing apparatus of a printing press. The fixing device is installed in parallel with the first roller so as to strongly fix the image of the developer transferred to the paper onto the paper while pressurizing and advancing the cylindrical first roller and the paper entered between the first roller and the paper. And a cylindrical second roller having a heater capable of heating the surface thereof, and rotatably installed while maintaining contact with the roller to increase heating ability of the first or second roller. An auxiliary preheating roller can be provided. According to the fixing device of the printing press, it is possible to shorten the time required to heat the fixing roller surface to its target temperature after starting, thereby shortening the preparation time of the print job.

Description

Fusing apparatus of printer

The present invention relates to a fixing apparatus of an electrophotographic printing press, and more particularly, fixing of a printing press capable of shortening a heating time for increasing a surface temperature of a roller for fixing an image formed of a developing material to a paper to a target temperature. Relates to a device.

A general electrophotographic printer is shown in FIG.

Referring to the drawings, the printing machine is adjacent to the circulation path of the photosensitive belt 14, which is circulated by three rollers 11, 12, 13 arranged in a triangular shape, and the reset device 15, optical scanning The devices 16, the developing devices 17, the drying device 18, and the fixing device 20 are arranged.

Looking at the printing process, first, the optical scanning device 16 scans the light corresponding to the image information to be printed on the predetermined area of the photosensitive belt 14 through the reset device 15 for initializing the new electrostatic latent image do. Through this process, the electrostatic latent image is formed on the photosensitive belt 14. Thereafter, the developer 17 supplies a toner or a liquid developer in a solid state onto the photosensitive belt 14 in the area where the electrostatic latent image is formed to develop an image. Then, the image developed by the continuous circulation of the photosensitive belt 14 is transferred from the photosensitive belt 14 to the first roller 21. The image transferred to the first roller 21 is transferred to the paper 23 entering between the first roller 21 and the second roller 22 by a paper feeder (not shown), so that the desired image is transferred to the paper 23. ) Is printed.

In the printing machine capable of performing the printing process as described above, the fixing device 20, that is, the first roller 21 and the second roller 22 of the conditions that each device must be equipped to enable a normal printing operation In the case of, the surface should be maintained at the set target temperature respectively.

After the system is powered up, the time to prepare for each device to start up and recover its working conditions is different for each device. Normally, the apparatus is controlled to wait for each device started at the same time as the power-on to complete all the working conditions, and then start a print job from the optical scanning of the optical scanning device 16 corresponding to the image information.

In the conventional fixing device 20, the fixing of the image transferred from the first roller 21 to the paper 23 onto the paper may be performed by mutual thermocompression bonding of the first roller 21 and the second roller 22. The heaters 21a and 22a, which can heat the surfaces of the first roller 21 and the second roller 22, are respectively incorporated. In order to obtain normal print quality, the surface temperature of the first roller 21 should be maintained at 80 ° C., and the surface temperature of the second roller 22 should be maintained at about 100 ° C.

However, conventionally, the heaters 21a and 22a having the same heating capability are incorporated in the rollers 21 and 22 so that the surface of the first roller 21 after the heaters 21a and 22a is started. Since the surface temperature of the second roller 22 takes more time to reach 100 ° C. than the heating time of reaching a target temperature of about 80 ° C., there is a problem of delaying the time required for preparing the work.

The present invention was devised to improve the above problems, and improves the heating capability of the surface of the rollers having a relatively high target temperature among the rollers requiring heating so that the surface of each roller is almost equal to the target temperature after starting. It is an object of the present invention to provide a fixing apparatus of a printing press which shortens the work preparation time by reaching.

1 is a cross-sectional view showing a conventional electrophotographic printing press,

2 is a cross-sectional view showing a fixing device of an electrophotographic printing press according to the present invention,

Figure 3 is a perspective view showing an auxiliary pre-roller of the fixing device of one embodiment according to the present invention,

4 is a perspective view showing the auxiliary pre-roller of the fixing device of the second embodiment according to the present invention,

5 is a perspective view showing an auxiliary pre-roller of the fixing device of the third embodiment according to the present invention.

6 is a perspective view showing an auxiliary pre-roller of the fixing device of the fourth embodiment according to the present invention.

<Description of Symbols for Major Parts of Drawings>

11, 12, 13: roller 14: photosensitive belt

15: Reset device 16: Gwangju company unit

17: developing unit 18: drying apparatus

20, 40: fixing device 21, 41: first roller

21a, 22a, 41a, 42a: heaters 22, 42: second roller

23, 30: paper 50: auxiliary pre-roller

51: shaft 52: heating layer

52a, 52b: electrode layer region 52c: hot wire band

53: contact layer 61, 62: electrode

70: power

In order to achieve the above object, according to the present invention, the cylindrical first roller and the first roller and the paper entering between the press while advancing the image of the developer material transferred to the paper to firmly fix the image to the paper; A fixing apparatus of a printing press provided with a cylindrical second roller having a heater mounted thereon, the side being parallel to the first roller, and having a heating capacity for the surface of the first roller or the second roller. The auxiliary pre-roller is further provided to be rotatable while maintaining contact with the roller to increase the pressure.

Preferably, the auxiliary preheating roller is a cylindrical shaft, a heat generating layer concentrically coated on the shaft with a material that is generated by the supplied electric power, and the upper surface of the heating layer is in contact with the fixing roller With layers.

Hereinafter, a fixing apparatus of an electrophotographic printer according to the present invention will be described in detail with reference to the accompanying drawings.

2 is a cross-sectional view showing the fixing device of the electrophotographic printing machine according to the present invention. Elements denoted by the same member number as in the above-described drawings represent the same element.

Referring to the drawings, the printing machine is adjacent to the circulation path of the photosensitive belt 14 which is circulated by three rollers 11, 12, 13 arranged in a triangle as shown in FIG. 15), the optical scanning devices 16, the developing devices 17, the drying device 18, the fixing device 40 is arranged.

The fixing device 40 includes a first roller 41 in which a portion of the photosensitive belt 14 is maintained and rotated, and a fixing second roller 42 and a second roller positioned above the first roller 41. The auxiliary preheat roller 50 is provided so that the roller 42 and a part thereof may be rotated while maintaining a contact state.

Heaters 41a and 42a are built in the first roller 41 and the second roller 42 so as to heat the surfaces thereof, respectively. The heaters 41a and 42a are light sources that emit radiant energy, for example, halogen lamps are applied.

The structure of the auxiliary preheating roller 50 installed to rotate in contact with the second roller 42 in order to increase the heating capacity of the surface of the second roller 42 will be described with reference to the embodiments illustrated in FIGS. 3 to 6.

Referring to FIG. 3, the auxiliary preheating roller 50 has a heat generating layer 52 formed concentrically on the shaft 51. Two electrodes 61 and 62 having a shape corresponding to the outer circumferential surface of the heat generating layer 52 are provided so as to maintain contact with the heat generating layer 52 at both edge regions of the heat generating layer 52. Accordingly, power may be supplied from the power supply 70 to the heat generating layer 52 through the two electrodes 61 and 62 even with the continuous rotation of the auxiliary preheating roller 50. The heat generating layer 52 is formed of a material that generates heat by the supplied electric power. The material for the heat generating layer 52 may be applied with various resistance materials, for example, nickel / chromium alloy.

Referring to FIG. 4, which shows another structure of the auxiliary preheating roller 50, the auxiliary preheating roller 50 is formed by sequentially stacking the heating layer 52 and the contact layer 53 concentrically on the cylindrical shaft 51. It has a structure.

The exposed portions on both sides of the heat generating layer 52 correspond to the outer circumferential surface of the heat generating layer 52 so that electric power can be continuously supplied from the power supply 70 to the heat generating layer 52 even with the rotation of the auxiliary preheating roller 50. Two electrodes 61 and 62 having a contact therebetween are provided to maintain contact with the heat generating layer 52, respectively. The heat generating layer 52 is formed of a material, for example, nickel / chromium alloy, which generates heat by electric power supplied from the power source 70. The contact layer 53 is formed of a material, for example, a rubber material or the like, which moderates the rapid temperature rise of the heat generating layer 52. Therefore, the heat of the temperature relaxed by the contact layer 53 is transmitted to the fixing roller 42, thereby preventing the surface of the fixing roller 42 from being damaged by excessive heat.

On the other hand, the structure of the auxiliary preheating roller 50 for improving the heat generating capacity of the heat generating layer 52 is shown in FIG.

Referring to FIG. 5, the auxiliary preheating roller 50 has a heat generating layer 52 formed concentrically on the cylindrical shaft 51. The heating layer 52 connects the electrode layer regions 52a and 52b formed at both edge regions of the shaft 51 and the electrode layer regions 52a and 52b along the longitudinal direction of the shaft 51. It has a plurality of hot wire bands 52c formed radially at angular intervals. The hot wire strip 52c is also formed of a material, for example, nickel / chromium alloy, which is generated by electric power supplied from the power source 70 through the electrodes 61 and 62 and the electrode layer regions 52a and 52b. The structure of the plurality of hot wire strips 52c improves the heat generating ability by increasing the resistance. The area 52d between the hot wire strips 52c is filled with a suitable material such as rubber. On the other hand, the contact layer 53 made of a rubber-like material is placed on the heat generating layer 52 having the hot wire band 52c structure in order to smooth the temperature rise of the heat generating layer 52 and to make the surface temperature as a whole. The formed structure is shown in FIG.

The rate of increase in the surface temperature of the second roller 42 is transferred to the second roller 42 by one of the auxiliary preheating rollers 50 selected and mounted among the auxiliary preheating rollers 50 described with reference to FIGS. 3 to 6. It is possible to increase the temperature increase rate only by the built-in heater 42a. Accordingly, when the auxiliary preheating roller 50 is operated together with the heater 42a of the second roller at the time of initial startup, the surface temperature rise of the second roller 42 is further accelerated to shorten the work preparation time. Target temperature at which the first roller 41 and the second roller 42 are set, for example, the surface temperature of 80 ° C. for the first roller 41 and the surface temperature of 100 ° C. for the second roller 42 simultaneously. The heating capacity of the heaters 41a and 42a and the auxiliary preheating roller 50 are appropriately adjusted so as to reach them.

After the initial preheating process, that is, after the second roller 42 reaches the set target temperature required for printing, the operation of the auxiliary preheating roller 50 and the built-in heater 42a is appropriately controlled to maintain the target temperature. Just do it.

Unlike the illustrated example, when the first roller 41 requires a relatively higher target temperature than the second roller 42, or the heater 41a embedded in the first roller 41 is the second roller 42. In the case where a heating capacity lower than that of the heater 42a incorporated therein is adopted, the auxiliary preheating roller 50 is installed and used to contact the first roller 41 so as to increase the heating capacity of the first roller 41. Can be.

Unlike the illustrated example, a transfer apparatus for transferring an image formed on the photosensitive medium to paper while rotating in contact with the photosensitive medium such as the photosensitive belt 14 and the photosensitive drum (not shown) is provided, and the paper in front of the transfer device. The fixing device may be disposed and used to fix the transferred image.

As described above, according to the fixing device of the printing press according to the present invention, the time required for heating the surface of the roller to its target temperature after starting can be shortened, so that the preparation time for printing can be shortened.

Claims (5)

The cylindrical first roller and the first roller and the paper entering between the rollers are installed to face the first roller side by side so as to strongly fix the image of the developer transferred to the paper onto the paper while pressing forward the paper entered therebetween. In the fixing apparatus of the printing machine having a cylindrical second roller with a built-in heater capable of heating the In order to increase the heating capacity of the surface of the first roller or the second roller is further provided with an auxiliary pre-roller is rotatably installed to maintain the contact with the roller to heat the surface of the roller, The auxiliary preheat roller A cylindrical shaft; And a heat generating layer having a plurality of hot wire strips radially formed at predetermined angular intervals, the electrode layer regions formed at both edge regions of the shaft and connecting the electrode layer regions along the longitudinal direction of the shaft. Fixing device for printing presses. The fixing apparatus of claim 1, wherein the hot wire strip is formed of a nickel / chromium alloy. The fixing apparatus of claim 1, further comprising a contact layer coated on an upper portion of the heat generating layer and having a surface thereof in contact with the roller. The fixing apparatus of claim 3, wherein the contact layer is formed of a rubber material. The method of claim 1, wherein the first roller is installed so that the photosensitive medium and a portion thereof are rotated in contact with the photosensitive medium so as to transfer the image of the developing material formed on the circulating photosensitive medium to the paper. Fixing apparatus for a printing press, characterized in that the heater is built.