JPH06194902A - Image forming device - Google Patents

Abstract

PURPOSE:To control the drive of a heating means and simultaneously, to display time information on drive on a control panel by inputting the actuation starting time of the heating means for preventing dew condensation through the key operation of the control panel. CONSTITUTION:When a user suspends a copying machine in a closing time, etc., the user inputs a specified time t2 from the next opening time, that is, a time lapsing from the present time to that time on the control panel, before a main switch is turned off, so that the dew condensation occurs inside the copying machine, a heating device is turned on before a minimum of time or above required for eliminating the dew condensation after the heating device is turned on. Thus, when a time t1 is set on a timer and the time of the control of the timer is up, an MPU receives a signal from the timer and generates a control signal for supplying electric power to the heating device again. Consequently, the user can obtain the copying machine for a normal image in a short waiting time just after working is started and evade the futile consumption of the electric power for heating.

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 using an electrostatic transfer process such as an electrostatic copying machine or an electrophotographic printer.

[0002]

2. Description of the Related Art Conventionally, in an apparatus such as a copying machine, when a heating device is operated in the early morning or the like in a low temperature environment such as winter, the copying machine left unattended overnight. Since the internal parts are completely cold, condensation occurs on the photosensitive drum, mirror, lens, etc. As a result, in order to prevent the occurrence of abnormalities in the image, it is usual to take measures to dispose the heating device inside the photosensitive drum, near the surface thereof, or near optical members such as mirrors and lenses. .

In addition to this, in an apparatus using an amorphous silicon photoconductive layer, by repeating copying processes such as charging, image exposure, development and transfer, the surface of the photoconductor becomes sensitive to humidity and moisture is removed. It becomes easy to adsorb on the surface. As a result, the surface resistance is lowered, and the surface charges are moved laterally to cause image deletion. This tendency is particularly remarkable when the humidity is high. It is considered that the reason for this is that negative ions and positive ions generated by corona discharge are adsorbed on the surface of the photoconductor to generate HNO ₃ , which adsorbs water. Therefore, in order to avoid the above-mentioned problems, a measure is taken to remove the moisture adsorbent such as negative ions or positive ions or HNO ₃ generated by corona discharge by providing a heater inside the photosensitive member to heat the same.

[0004]

However, in the conventional apparatus, in order to avoid the above-mentioned inconvenience, it is necessary to always connect the copying apparatus to the power source to control the operation of the heating apparatus. For this reason, power is consumed to operate the heating device even at night when the copying device is not used. Such a so-called useless consumption of electric power is caused by a social situation where resource saving and energy saving are required in recent years.
A solution is urgently needed.

Therefore, in order to solve the above problems, Japanese Patent Publication No.
In the one disclosed in Japanese Patent Laid-Open No. 3-59144, by providing a dew condensation sensor, even if the dew condensation occurs as described above in the state where the connection with the main power supply at night is turned off, this dew condensation immediately after the power supply is connected. It introduces the control that detects by the sensor, operates the heating device, and prohibits the copying operation until the dew condensation is resolved. However, in the above apparatus, the waiting time from the connection of the power source to the removal of the dew condensation is different from the warm-up time for heating the fixing roller of a normal copying apparatus, and cannot be accurately grasped.

[0006]

SUMMARY OF THE INVENTION The present invention, which is solved as the above-mentioned conventional problem, is an image forming apparatus for forming an image by an electrophotographic method having a heating means for preventing dew condensation, and the operation of the heating means is started. The time is input by operating the keys on the operation panel, the drive of the heating means is controlled based on the signal accompanying this input, and the time information regarding the drive is displayed on the operation panel. As an example of displaying the time on the operation panel, it is possible to display the scheduled use time, the time at which the heating drive is disclosed, or the time until the heating drive is started.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the inside of a microprocessor unit for controlling a copying machine to which the present invention is applied. Microprocessor unit (MPU) 50
Has a calculation unit (CPU) 51 having a calculation and determination function, a read only memory (ROM) 52 for storing a processing program, a random access memory (RAM) 53 for storing data, and a signal transmission / reception with an external device. It has an input / output port for performing. Furthermore, timer IC5
4 is built in, and the timer is set by an instruction. The basic operation of the MPU 50 is already known and will not be described.

FIG. 2 is a flow chart of a general copying machine.
When the main switch of the copying machine is turned on, the main switch is reset and the operation mode of the MPU 50 is initialized, and then the initial check routine is started. In this check, first, the presence or absence of toner, transfer paper, etc. is checked, and then, if the mirror base, the paper feed deck, etc. are not in a predetermined state, the motor clutches are driven to set the initial state. A fixing unit having a heater continues to stand by until a predetermined temperature is reached, and detects the temperature and humidity to set the voltage applied to the charging device and the bias potential of the photoconductor.

Next, the number of copies data and the copy mode are set, and when the start switch is turned on, the sequence control for performing copying by sequentially executing the known copying process including charging, exposure, transfer, charge removal and fixing. In addition, we regularly check for paper jams and open / close safety switches. When the above copying process is completed, the counter data is checked, and if the predetermined number of copies is completed,
After the copy operation is completed, the initial check routine is entered to prepare for the next start.

In the copying apparatus of the present invention, the CPU 51 and the program timer 54 control the operation of the heating device such as the photosensitive drum, the mirror and the lens. That is, as the heating device, a cylindrical sheet heater or a mirror mounted inside the photosensitive drum, a cement resistor arranged near the surface of the drum, or the like is used, which is arranged at each part.

The structure of the heater in the photosensitive drum will be described with reference to FIGS. 5 and 6 as an example of the heating device.

The photosensitive drum 3 is, as shown in FIG. 5, a cylindrical cylinder 10, left and right flanges 12L and 12R fixed to both end surfaces of the cylinder 10 and mutually connected by a middle stay 11, and both flanges 12L. The left and right rotary shafts 13L and 15R protruding from the support plate 6 of the case main body 2 are fitted to the bearing shafts 15L and 15R.
By being fitted in the support holes 6a and 6b of L and 6R, the entire photosensitive drum 3 is rotatably supported by the process unit main body. A planar heater 16 is arranged on the inner peripheral surface of the cylinder 10 of the photosensitive drum 3,
The planar heater 16 is connected to a temperature control board 17 which is supplied with power via an electrode 19. Sliding ends 19 a and 19 b project from the electrode 19, and these sliding ends 19 a and 19 b are projected.
Since the a and 19b are in sliding contact with the two rings 7a and 7b (see FIG. 6) of the slip ring 7 fixed to the process unit main body, the heater 1
6 can be supplied with electric power.

The heating device having the above-described structure is turned off at the same time as the main switch of the copying machine is turned off (to = 0 in FIG. 3) or, if necessary, after a predetermined time (to) has passed since the main switch was turned off. It is controlled by the MPU. Further, as shown in FIG. 4, in addition to the various setting keys of the conventional copying machine, the operation panel of the copying machine has an arbitrary time (t) after the main switch of the heating device is turned off.
1) A timer set key 95 for enabling the timer to set the elapsed time so that it is turned on again after the elapsed time.
And 7-segment display device 72 capable of displaying numerical values and alphabetic characters and displaying the timer set time in addition to the display of the number of copies etc. in the conventional device. Further, for changing and designating the timer set value. Up and down keys 96 and 97 are arranged.

Then, in response to an input signal from the timer set key 95, the MPU 50 sends a command to the program timer IC 54 and the timer is set there.

FIG. 3 is a timing chart showing the operation timing of the above copying machine.

According to the above sequence, the user sets a predetermined time (t2 in FIG. 3) before starting the next work (for example, the next day) before turning off the main switch when the copying machine is stopped for a long time such as at the end of work. That is, when the inside of the copying machine is dewed, the heating device should be turned on at least as long as the heating device is turned on until the dew condensation is eliminated, or before the heating device is turned on. Enter the elapsed time from the present on the operation panel. Thus, if the time t1 is set by the timer, the MPU receives a signal from the timer at the time when the timer control times up, and issues a control signal to supply the electric power to the heating device again. As a result, the user can obtain a copy of a normal image with a shorter waiting time than immediately after starting work, and when the copying machine is not used for a long time such as at night compared to the conventional apparatus, the heating device is turned off. Can be kept. This greatly contributes to energy saving, and it is possible to guarantee high safety.

(Other Embodiments) In the above embodiment, the elapsed time from the end of work to immediately before the start of work is input, but this may be set as follows.

That is, before the user turns off the main switch at the end of work, the timer can be set by inputting the time of the next start at the operation unit. As a recent copying machine, a copying machine having a calendar IC 55 and capable of displaying the current time on a liquid crystal display section or the like on the operation section has been commercialized. And MP with this calendar IC
In U, the time difference is calculated from the start time input by the user and the time at the time of input. Along with this, from the time difference obtained by this arithmetic processing, the time more than the minimum time required for the dew condensation to be eliminated after the heating device is activated or longer-previously input to the memory of the MPU- By controlling such that the time obtained by subtracting is set by the timer, the same effect as in the first embodiment can be obtained. Further, in this embodiment, since the time can be input, the user can set the time from the activation of the heating device to the time when the dew condensation is eliminated and the time from the end of work to the start of work as in the first embodiment. Since there is no troublesomeness in setting the timer in consideration of the time difference, there is an effect that it is possible to provide a copying apparatus which is easy to use.

Further, in the above-described embodiment, by configuring the timer setting contents to be input to the RAM of the MPU once, it is possible to save the trouble of inputting the time to be set each time only by pressing the timer set key 95. The effect is obtained.

[0020]

As described above, according to the present invention, the heater for dehumidifying and preventing dew condensation is turned off at the same time as the main switch of the copying machine main body is turned off at the same time, and the operation for setting the start time of the heater is set. A key is provided. Furthermore, the input signal from this operation key enables the heater to be turned on again after a predetermined time, so there is no unnecessary power consumption for driving the heater at night, etc. There is an effect that a copying machine can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram showing a control unit of a copying apparatus embodying the present invention.

FIG. 2 is a control flowchart of a general copying apparatus.

FIG. 3 is a timing chart showing the drive timing of the heating device of the copying machine that is the embodiment of the present invention.

FIG. 4 is a plan view of an operation panel of a copying apparatus that is an embodiment of the present invention.

FIG. 5 is a sectional view of a photosensitive drum of a copying apparatus that is an embodiment of the present invention.

6A is a plan view of a sliding electrode of the photoconductor of FIG.
(B) is the sectional view on the AA line of (a).

[Explanation of symbols]

 3 drum 16 drum heater 50 microprocessor unit 54 timer IC 70 operation panel 95 timer set key 96, 97 up / down key

Claims (3)

[Claims] 1. An image forming apparatus for forming an image by an electrophotographic method having a heating means for preventing dew condensation, wherein an operation start time of the heating means is inputted by a key operation of an operation panel, and the operation is accompanied. An image forming apparatus, characterized in that the driving of the heating means is controlled based on the signal and time information regarding the driving is displayed on the operation panel. 2. The image forming apparatus according to claim 1, wherein the time information in claim 1 is a time until the heating means is activated. 3. The operation start time input according to claim 1, wherein the operation start time is set by inputting the use time of the apparatus main body in the input operation so that there is no dew condensation in the use start time. The image forming apparatus according to claim 1.