JP2003307898A - Image forming device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To suppress power consumption in an existing device configuration to be equal to or less than power obtained from a power supply. A plurality of stations (58, 59, 60, 61) having a drum heater (10) for forming an image on a transfer material (P), and a heater (72).
For fixing a formed image to a transfer material P by heating
63, the plurality of stations 58, 59, 60, depending on the fixing mode of the fixing device 63.
It is characterized by having a controller 80 for controlling each of the 61 drum heaters 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus having control means for regulating the power consumption of the image forming apparatus.

[0002]

2. Description of the Related Art A conventional example will be described with reference to the drawings. In FIG. 8, the toner images formed at the stations 208, 209, 210, 211 as image forming units for forming an image on the transfer material are
It is transferred onto the transfer material P fed to the transfer belt 206 at a predetermined timing by the registration rollers 202. Then, the transfer material P that has received the transfer of the toner image is separated from the transfer belt 206 by the separation charging device 213, and then is conveyed to the fixing device 212, where the toner image is fixed by the fixing device 212, and a final image is obtained.

Next, a description of each station will be given.
208 will be described as an example. The surface of the photoconductor drum 251 is uniformly charged by the primary corona charger 252. afterwards,
Laser exposure 253, which is image exposure corresponding to the original, is generated by exposure means having a semiconductor laser, a mirror, and a lens (not shown), and this laser exposure 253 is radiated onto the photoconductor drum 251 and statically placed on the photoconductor drum 251. A latent image is formed.

Then, the electrostatic latent image is developed by the developing device 254 to be visualized as a toner image, and the toner image is transferred onto the transfer belt 206 by the registration roller 202 at a predetermined timing. The photoconductor drum 251
The image is transferred by a transfer charger 255 that is disposed opposite to
The transfer residual toner remaining on the photosensitive drum 251 is removed by the drum cleaning device 256, and the residual potential is removed by light irradiation by the pre-exposure lamp 257.
Prepared for the next image formation.

The transfer material P is selected and fed from four feeding portions. The feeding unit includes feeding cassettes 203, 204, 205 for loading transfer materials of standard sizes, and a manual feed tray capable of loading transfer materials of the minimum feeding size to the maximum feeding size.
With 201.

In the image forming apparatus as described above, the parts inside the image forming apparatus that have been left overnight for more than one night in a low temperature environment such as winter are completely cooled.
Condensation may occur on the photoconductor drum, mirror, lens, etc. immediately after the power is turned on. As a result, irregular reflection, double bending, etc. occur in the mirrors and lenses, which causes abnormal image exposure and the electrostatic latent image on the photoconductor drum 251 is not formed correctly, or even when the image exposure is correctly irradiated.
251 If dew condensation occurs on the surface, the electrostatic latent image may not be formed correctly, and the resulting image may be blurred.

In addition, by repeating image forming processes such as charging, exposure, development, transfer and cleaning for a long period of time, the surface of the photoconductor drum 251 becomes hypersensitive to moisture and easily adsorbs moisture on the surface. . as a result,
Since the surface resistance decreases, the surface charge moves in the axial direction, which causes a problem of so-called image deletion in which an image is blurred. This phenomenon is particularly remarkable when the humidity is high.

The reason for this is that the primary charger 252, the transfer charger 255, or the auxiliary used mainly for controlling the charge of the developer between the processes of development and transfer and the processes of transfer and cleaning. Products such as ozone generated by the corona discharger as a charger are the photoconductor drums.
It is considered that water adheres to the surface of the photoconductor drum 251 or the resin or the additive contained in the toner or the additive contained in the transfer material P adheres to the photosensitive drum 251.

There is also a problem that the charging potential and the sensitivity during image exposure change depending on the temperature of the photosensitive drum 251. On the other hand, when forming an image with higher image quality, if the temperature of the optical system such as the semiconductor laser for exposure, mirrors, and lenses is kept constant, expansion and contraction due to temperature will be suppressed and the laser light amount and position accuracy will be improved. Has the effect of increasing.

Further, when the transfer material P stored in the feeding cassette absorbs moisture, the electrical resistance is lowered, so that the transfer current through the transfer material P interferes with the separation charger 213 and is a guide for guiding the feeding. There is a problem of so-called transfer omission in which transfer efficiency is lowered due to leakage through a member or a feeding roller for feeding the transfer material.

Therefore, in order to avoid the above problems or to realize higher image quality, the vicinity of the optical system or the photosensitive drum is provided.
By providing a heater inside or in the vicinity of 251 for heating, measures are taken to prevent water adsorption on the photosensitive drum 251, stabilization of charging potential and sensitivity, stabilization of optical system, and prevention of moisture absorption of the transfer material P. ing.

[0012]

However, the conventional example has the following problems. That is, it is required to increase the power consumption required for the entire device for various reasons described below. However, on the other hand, there is a limit to the electric power that can be obtained from the power source.

(Reason for Increase in Power Consumption) 1. As the number of images obtained per unit time increases, the amount of power supplied from the fixing device to the transfer material increases.

2. Increasing the size of the apparatus As the size of the transfer material on which an image is formed increases, the size of the apparatus increases, and the size of the fixing device, which consumes a large amount of power, increases, and the power consumption increases proportionally.
Further, as the size and speed of the device increase, each drive device also has a larger capacity, which is one of the causes of the increase in power consumption.

3. Highly functional equipment As the number of parts increases, so does the power consumption.

To solve the above problems, the current value is reduced by improving the efficiency of the device configuration, the drive system is developed to obtain the required power and speed with a smaller power consumption, the power consumption is reduced by the integration of electrical parts, etc. Efforts have been made, but they are not always sufficient.

Therefore, an object of the present invention is to suppress the power consumption in the existing device configuration to be equal to or less than the power obtained from the power source.

[0018]

In order to achieve the above object, a typical constitution of the present invention has a plurality of stations for forming an image on a transfer material and a fixing heating means. An image forming apparatus having a fixing unit configured to heat and fix the formed image on a transfer material is characterized by further including a control unit that controls each heating unit of the plurality of stations according to a fixing mode of the fixing unit.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) (Overall Structure and Operation of Image Forming Apparatus) An image forming apparatus of the present invention will be described by exemplifying a copying machine with reference to the drawings. As shown in FIG. 2, in the image forming apparatus 50, stations 58, 59, 60, 61 as image forming units that form an image on the transfer material P.
The toner image formed in (1) is transferred by the registration roller 52 onto the transfer material P fed to the transfer belt 56 at a predetermined timing. Then, the transfer material P that has received the transfer of the toner image
After being separated from the transfer belt 56 by the separation charging device 62, the toner is conveyed to a fixing device 63 as a fixing unit having a fixing roller 64, and the toner image is fixed by the fixing device 63 to obtain a final image. Further, each of the stations 58, 59, 60, 61 and the fixing device 63 is provided with a temperature control unit described later, and the temperature is controlled by a controller 80 as a control means.

Next, the inside of the stations 58, 59, 60, 61 will be described. As shown in FIG. 3, each station forms an image on the transfer material P, so that the photosensitive drum 1, the primary corona charger 2, the laser exposure 3, the developing device 4, the transfer charger 5, the drum cleaning device 6, It has a pre-exposure lamp 7.

The surface of the photosensitive drum 1 is uniformly charged by the primary corona charger 2. After that, a laser exposure 3 which is an image exposure corresponding to the original is a semiconductor laser (not shown),
The laser exposure 3 generated by the exposure unit having a mirror and a lens is irradiated onto the photosensitive drum 1 to form an electrostatic latent image on the photosensitive drum 1. Then, the electrostatic latent image is developed by the developing device 4 to be visualized as a toner image, and the toner image is exposed to the transfer material P fed onto the transfer belt 56 by the registration roller 52 at a predetermined timing. The image is transferred by the transfer charger 5 arranged so as to face the body drum 1. The transfer residual toner remaining on the photosensitive drum 1 is removed by the drum cleaning device 6, and the residual potential is removed by light irradiation from the pre-exposure lamp 7 to prepare for the next image formation.

The transfer material P is selected and fed from four feeding portions. As the feeding unit, there are feeding cassettes 53, 54, 55 for loading transfer materials of standard sizes, and a manual feed tray 51 capable of loading transfer materials of the minimum feeding size to the maximum feeding size.

As shown in FIGS. 4 and 5, a drum heater is provided inside the photosensitive drum 1 as a heating means for the heat transfer wire or the like.
Having 10. A temperature sensor 8 is arranged near the photosensitive drum 1 to detect the temperature of the surface of the photosensitive drum 1 and the temperature of each station. Further, the electricity to the drum heater 10 is supplied through the rear end flange 12 of the photosensitive drum 1. The contact 13 attached to the main body of the image forming apparatus 50 slides in accordance with the rotation of the rear end flange 12 to energize the drum heater 10.

(Structure and Operation of Temperature Control Section) As shown in FIG. 1, each of the stations 58, 59, 60, 61 has a temperature sensor 8 for detecting the temperature in the vicinity of the photosensitive drum 1 and the photosensitive drum 1. And a heater circuit 9 for operating the power source of the drum heater 10 provided inside the drum heater 10. Further, the fixing device 63 includes a temperature sensor 70 for detecting the temperature in the vicinity of the fixing roller 64, a heater 72 as a fixing heating means arranged inside the fixing roller 64, and a heater circuit 71 for operating the power source of the heater 72. Have.

The temperature of the fixing device 63 is controlled by the controller 80 sending a control signal 63b to the heater circuit 71 based on the detection signal 63a of the temperature sensor 70. Specifically, if the temperature detected by the temperature sensor 70 is below a predetermined temperature (for example, 180 ° C.), the controller 80
Sends a control signal 63b for turning on the power of the heater 72 to the heater circuit 71, and when the temperature exceeds a predetermined temperature, the controller 80 sends a control signal 63b for turning off the power of the heater 72 to the heater circuit 71.

The temperature of each station 58, 59, 60, 61 is controlled by the controller 80 for each heater circuit 9 based on the control signal 63b of the fixing device 63 and the detection signal 14 of the temperature sensor 8 of each station. This is done by sending a control signal 15. This will be specifically described with reference to FIG.

As shown in FIG. 6, when the control is started, the controller 80 first determines whether or not the power source of the heater 72 of the fixing device 63 is turned on (determination 101). When the power of the heater 72 is off, the controller 80 can turn on the power of the drum heaters 10 arranged in all the stations where the temperature of the photosensitive drum 1 is a predetermined value (for example, 36 ° C.) or less (determination). 106, processing 107, 108). Also, the heater 72
When the power is turned on, the controller 80 detects the temperature of each station (decision 102). At this time, if there are two or more stations having a temperature lower than the predetermined value (decision 103), the controller 80 turns on the drum heaters 10 of the two stations in order from the station having the lowest temperature (process 105), and the temperature is below the predetermined value. When there are no two or more stations having the temperature (decision 103), the power of the drum heater 10 of one station having a temperature equal to or lower than the predetermined value is turned on (process 10).
Four).

The timing of turning on the power of each drum heater 10 when it is controlled by the controller 80 will be described. As shown in FIG. 7, when the power of the heater 72 of the fixing device 63 is turned on and the temperatures of all the stations are below a predetermined value (for example, 36 ° C.) (timing 151), two drum heaters 10 are provided. Only the power is turned on until the power is turned on, and the drum heaters 10 of the two stations are turned on from the lowest temperature. Further, when the power of the heater 72 of the fixing device 63 is turned off and the temperatures of all the stations are equal to or lower than a predetermined value (timing 152), the power of the drum heater 10 can be turned on in all the stations. Turn on the drum heater 10 of the station.

The heater 72 of the fixing device 63 is powered on,
When only the temperature of the station 60 is below the predetermined value (timing 153), the drum heater 10 of the station 60 only
Can be turned on. Also, the heater of the fixing device 63
When the power of 72 is turned on and the temperature of the stations 60 and 61 is below the predetermined value (timing 154), the drum heaters of the stations 60 and 61 are
Only 10 can be turned on.

As described above, since the controller 80 for controlling the drum heaters 10 of the plurality of stations 58, 59, 60, 61 according to the fixing mode of the fixing device 63 is provided, the power consumption in the existing apparatus configuration can be obtained from the power source. It can be kept below the required power.

Further, the controller 80 has a predetermined number (for example, two) below a predetermined temperature (for example, 36 ° C.) among the plurality of stations when the fixing heating means is powered on.
Since the drum heaters 10 of the following stations are powered on, and when the heater 72 is powered off, the drum heaters 10 of all stations having a predetermined temperature or lower among the plurality of stations are powered on. As described above, the power consumption in the existing device configuration can be suppressed to be equal to or lower than the power obtained from the power supply.

(Other Embodiments) In the above-described embodiment, when the heater 72 of the fixing device 63 is turned off, the temperature of the photosensitive drum 1 is arranged in all stations whose temperature is below a predetermined value. The control is such that the drum heater 10 can be turned on, but the present invention is not limited to this. Regardless of the temperature of the photosensitive drum 1, when the heater 72 of the fixing device 63 is turned off, all stations are turned on. Drum heater
It may be a control to turn on the power of 10.

Further, in the above embodiment, the image forming apparatus according to the present invention is exemplified by the copying machine, but the image forming apparatus is not limited to this, and may be an image forming apparatus such as a facsimile machine or a printer.

Further, in the above embodiment, the fixing device 63
The number of stations that can turn on the drum heater 10 when the heater 72 is turned on is two, and the predetermined temperature of the fixing device 63 and the station is 180.
C. and 36.degree. C. are set, but the present invention is not limited to this, and can be freely set in consideration of the power consumption of the entire device.

In the above embodiment, the drum heater 10 is provided in the photosensitive drum 1 to control the temperature of the station. However, the present invention is not limited to this, and heating means is provided outside the photosensitive drum 1. It may be provided to control the temperature of the drum heater 10.

[0036]

As described above, in the present invention,
Since the control means for controlling each heating means of the plurality of stations is provided according to the fixing mode of the fixing means, the power consumption in the existing device configuration can be suppressed to be equal to or less than the power obtained from the power supply.

[Brief description of drawings]

FIG. 1 is a block diagram of a temperature control unit.

FIG. 2 is a schematic diagram of an image forming apparatus.

FIG. 3 is a schematic diagram of an image forming unit.

FIG. 4 is a configuration diagram of the inside of a photosensitive drum.

FIG. 5 is a configuration diagram of a photosensitive drum.

FIG. 6 is a flowchart of temperature control.

FIG. 7 is an explanatory diagram of the timing of turning on the power.

FIG. 8 is a schematic diagram of a conventional image forming apparatus.

[Explanation of symbols]

P ... Transfer material 1 ... Photosensitive drum 2 ... Primary corona charger 3 ... Laser exposure 4 ... Developer 5 ... Transfer charger 6 ... Drum cleaning device 7 ... Pre-exposure lamp 8… Temperature sensor 9 ... Heater circuit 10… Drum heater 12… Rear end flange 13 ... Contact 14… Detection signal 15… Control signal 50… Image forming device 51… Bypass tray 52… Registration roller 53… Feed cassette 54… Feed cassette 55… Feed cassette 56… Transfer belt 58… Station 59… Station 60… Station 61… Station 62… Separation charger 63… Fixer 63a ... Detection signal 63b ... Control signal 64… Fixing roller 70… Temperature sensor 71… Heater circuit 72… Heater 80… Controller 101… Judgment 102… Judgment 103… Judgment 104… Processing 105 ... Processing 106… Judgment 107… Processing 108… Processing 151… Timing 152… Timing 153… Timing 154… Timing

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2H027 DA03 DA13 EA15 EB04 EC20                       EF09 ZA01                 2H033 AA32 AA41 BA24 BB01 CA23                       CA26                 2H300 EB04 EB12 EJ01 EJ09 GG01                       GG41 GG48 QQ04 QQ10 QQ26                       RR02                 3K058 AA81 BA18 CA12 CA22 CB02                       GA06

Claims (3)

[Claims] 1. An image forming apparatus comprising: a plurality of stations having a heating unit for forming an image on a transfer material; and a fixing unit having a fixing heating unit for heating and fixing the formed image on the transfer material. An image forming apparatus comprising: a control unit that controls each heating unit of the plurality of stations according to a fixing mode of the fixing unit. 2. The image forming apparatus according to claim 1, wherein the control means controls the heating means of a predetermined number of stations or less of a predetermined temperature or less among the plurality of stations when the fixing and heating means is powered on. The image forming apparatus is characterized in that the heating means is turned on at all stations having a predetermined temperature or lower among the plurality of stations when the fixing heating means is turned off. 3. The image forming apparatus according to claim 1, wherein the control means controls the heating means of a predetermined number of stations or less of a predetermined temperature or less among the plurality of stations when the fixing and heating means is powered on. An image forming apparatus characterized in that the heating means of all stations of the plurality of stations are turned on when the power of the fixing heating means is turned off.