JPH0659548A - Dehumidifying controller on copying machine - Google Patents

Abstract

PURPOSE:To minimize the loss of electric power on dehumidifying and moreover, to take a proper dehumidifying action according to dew condensation. CONSTITUTION:A dew condensation state detecting photosensor 17 is provided in the vicinity of a final mirror 15 just before a photosensitive drum 16 on an optical unit part 10 having a front stage mirror 12, a lens 13 and a rear stage Mirror 14. A constitution is adopted so that a copying lamp 11 is transiently operated at the time of initializing a machine, to receive a reflected light quantity detecting level Li from the final mirror 15 at this time by the dew condensation state detecting photosensor 17, when the level Li is lower than a prescribed value, a dehumidifier is operated for a given time, and the temporary action of the copying action 11 and the operation of the dehumidifier are repeated until the reflected light quantity detecting level Li is higher than the prescribed value, and advancement toward a copying ready state is attained when the level Li is higher than the prescribed value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dehumidification control device for a copying machine.

[0002]

2. Description of the Related Art In a copying machine such as a PPC (Plain Paper Copier), dew condensation may occur inside the copying machine when the power is turned off. When dew condensation occurs, the lenses and mirrors in each part of the optical unit part become cloudy. If copying is performed in this state, the image quality of the copy will be poor. Therefore, dehumidification measures have been taken conventionally.

As a conventional dehumidification measure, a dehumidifying device including a resistance heating element is automatically turned on when the power is turned off to dehumidify it according to the amount of heat generated, and when the power is turned on to use the copying machine. Dehumidifier is automatically turned off
It was configured to stop the heat generation.

[0004]

As described above, in the conventional copying machine, the dehumidifying device is only turned on / off in synchronization with the turning off / on of the power source. It worked regardless of. In other words, the proper dehumidification control according to the dew condensation state was not performed.
For example, if the power of the copying machine is turned off at the end of the work on the first day, the dehumidifying device is continuously operating until the power is turned on the next day. This may not be a problem if it is a copier that is used in a constantly humid environment, but normally it is rarely used in such an environment, and even in an environment where condensation does not easily occur when the copier is not in use. This means that the dehumidifying device is continuously operated, which consumes electric power remarkably wastefully. On the other hand, in a humid area, reliable dehumidification is not performed only by the operation of the dehumidifying device when the power is turned off, and defective image quality may occur in the first copy when the use is resumed.

The present invention was devised in view of the above circumstances, and it is intended to reduce the power loss related to dehumidification as much as possible and to perform an appropriate dehumidification operation according to the state of dew condensation. With the goal.

[0006]

A dehumidification control device in a first copying machine according to the present invention includes a dew condensation state detecting optical sensor arranged in the vicinity of a final mirror immediately before a photosensitive drum in an optical unit, and a power source is turned on. A means for temporarily operating the copy lamp at the time of the machine initial operation, and a part of the exposure light emitted from the copy lamp and reflected from the final mirror through the optical unit section through the dew condensation state detecting optical sensor. Detecting means, a means for comparing the reflected light quantity detection level with a predetermined value, a means for shifting to a copy ready state when the reflected light quantity detection level is larger than a predetermined value, and a reflected light quantity detection level higher than a predetermined value. When it is smaller, the copy prohibition state is set and the dehumidifying device is operated, and the copy light is detected until the reflected light amount detection level becomes higher than a predetermined value. When it becomes larger than a predetermined value so repeated a dehumidifier operation and time-flop exemplary operation is characterized in that a means for shifting the copy ready state.

A dehumidification control device in a second copying machine according to the present invention comprises a dew condensation state detecting optical sensor arranged in the optical unit section in the vicinity of a final mirror immediately before the photosensitive drum.
A means for storing beforehand the data of the dew condensation characteristic showing the relationship between the detection level of reflected light quantity and the dehumidification time, a means for temporarily operating the copy lamp at the machine initial when the power is turned on, and a means for irradiating from this copy lamp. Means for detecting a part of the exposure light reflected from the final mirror through the optical unit section via the dew condensation state detecting optical sensor; means for comparing the reflected light amount detection level with a predetermined value; and Means for shifting to a copy ready state when the reflected light amount detection level is larger than a predetermined value, and dehumidifying time corresponding to the reflected light amount detection level from the storage means when the reflected light amount detection level is smaller than a predetermined value and a copy prohibited state is set. Read out and operate the dehumidifier for the dehumidification time, and move to the copy ready state after the dehumidification time elapses. It is characterized in that a means for.

A dehumidification control device in a third copying machine according to the present invention is an exposure sensor arranged in the vicinity of a lens in an optical unit section, and a dew condensation state detection arranged in the vicinity of a final mirror in front of a photosensitive drum in the optical unit section. Data for the dew condensation characteristic indicating the relationship between the dehumidification time and the difference between the detection level of the reference light amount by the exposure sensor and the detection level of the amount of light reflected from the final mirror by the dew condensation state detection optical sensor. Means and power on
Means for temporarily operating the copy lamp at the time of the machine initialization, means for detecting a part of the exposure light emitted from the copy lamp via the exposure sensor, and the final mirror through the optical unit section. Means for detecting a part of the exposure light reflected by the dew condensation state detection optical sensor, and a difference between the reference light amount detection level by the exposure sensor and the reflected light amount detection level by the dew condensation state detection optical sensor Means, a means for comparing the detection level difference with a reference value, a means for shifting to a copy ready state when the detection level difference is smaller than the reference value, and a copy prohibition when the detection level difference is larger than the reference value. In addition to the state, the dehumidification time corresponding to the detection level difference is read from the storage means and dehumidified over the dehumidification time. And means for operating the apparatus, is characterized in that a means for shifting the copy ready state after a dehumidifying time.

The dehumidification control device in the fourth copying machine according to the present invention comprises an exposure sensor arranged near the lens in the optical unit section and a dew condensation state detection arranged near the final mirror in the optical unit section immediately before the photosensitive drum. Data for the dew condensation characteristic indicating the relationship between the dehumidification time and the difference between the detection level of the reference light amount by the exposure sensor and the detection level of the amount of light reflected from the final mirror by the dew condensation state detection optical sensor. Means, means for pre-storing data of exposure amount correction characteristics indicating the relationship between the detection level difference and the exposure gain, and means for temporarily operating the copy lamp at the time of machine initializing when the power is turned on, A part of the exposure light emitted from the copy lamp is detected through the exposure sensor and the optical unit. A means for detecting a part of the exposure light reflected from the final mirror via the dew condensation state detection optical sensor, and a reference light amount detection level by these exposure sensors and a reflected light amount detection level by the dew condensation state detection optical sensor. A means for calculating a difference, a means for comparing the detection level difference with a reference value, a means for shifting to a copy ready state when the detection level difference is smaller than the reference value, and the detection level difference being larger than the reference value. Occasionally, a copy prohibition state is set, a dehumidification time corresponding to the detection level difference is read from the storage means, and a dehumidification device is operated over the dehumidification time; a means for shifting to a copy ready state after the dehumidification time elapses; With the operation of the copy key from the ready state, the above-mentioned temporary operation of the copy lamp and detection of the reference light amount are performed again. Detection of Bell and detecting the reflected light amount level, and means for calculating the detection level difference, is characterized in that a means for exposure control reads the exposure gain corresponding to the detected level difference.

[0010]

According to the first dehumidification control device, the exposure light from the copy lamp operated at the machine initial when the power is turned on is reflected by the final mirror and is incident on the dew condensation state detecting optical sensor. The reflected light amount detection level is the power supply OF.
It corresponds to the degree of clouding of the optical unit portion which is affected by the dew condensation condition occurring during F. When there is clouding, the amount of exposure light reflected by the final mirror also decreases, and the level of detection of the amount of reflected light from the final mirror by the dew condensation state detection optical sensor becomes smaller than a predetermined value. At this time, since the copy is prohibited, the copy operation is not performed even if the copy key is operated, and the occurrence of the copy with poor image quality is prevented. Then, the dehumidifying device is operated to dehumidify the inside of the copying machine. The temporary operation of the copy lamp and the operation of the dehumidifying device are repeated until the reflected light amount detection level becomes higher than a predetermined value and dehumidification is completed.

According to the second dehumidification control device, the dehumidifying time corresponding to the reflected light amount detection level, that is, the degree of clouding in the optical unit is stored in the storage means in advance, and the dew condensation state detecting optical sensor actually uses the dehumidifying time. The storage means is accessed based on the detected reflected light amount detection level, and the corresponding dehumidification time data is read. Then, after the dehumidifying device is operated for the dehumidifying time, it shifts to the copy ready state.

According to the third dehumidification control device, in addition to the optical sensor for detecting the dew condensation state immediately before the photosensitive drum, an exposure sensor near the lens in the optical unit section is provided. The difference between the reference light amount detection level by the exposure sensor and the received light amount detection level by the dew condensation state detection optical sensor corresponds to the degree of clouding in the optical unit. Data of the dew condensation characteristic indicating the relationship between the detection level difference and the dehumidification time are stored in advance, and the storage means is accessed based on the difference between the actually obtained reference light amount detection level and the received light amount detection level. Read the dehumidification time data. Then, after the dehumidifying device is operated for the dehumidifying time, it shifts to the copy ready state.

In any of the first to third dehumidification control devices, after the dehumidification operation is completed, the dehumidification control apparatus shifts to the copy ready state and enables the copy operation by the operation of the copy key. Can be copied at. In the power-off state, there is no need to perform the dehumidifying operation as in the conventional example, and since the dehumidifying operation is performed only when dew condensation occurs, there is no wasted power consumption.

According to the fourth dehumidification control apparatus, after the dehumidification is completed, the exposure amount correction for removing the influence of dirt is performed, and the detection level difference which is the basis of the correction is the same as the detection level difference which is the source of the dehumidification. The exposure sensor and the optical sensor for detecting the dew condensation state are used in common. Therefore, the structure can be simplified and the cost can be reduced.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a dehumidification control device in a copying machine according to the present invention will be described below in detail with reference to the drawings.

First Embodiment FIG. 1 is a perspective view showing the appearance of a PPC (Plain Paper Copier). In the figure, 1 is a copying machine main body, 2 is a front cover, 3 is an operation panel, 4 is a document stand, 5 is a document cover, 6 is a manual feed guide, 7 is a paper feed cassette, and 8 is a paper feed cassette.
Is a document receiver, and 9 is a copy receiver.

FIG. 2 shows the optical unit 10 and the photosensitive drum 1.
6 and 6 are shown. The optical unit section 10 includes a copy lamp 11
, Front mirror 12, lens 13, rear mirror 14
And the final mirror 15 immediately before the photosensitive drum 16. In the vicinity of the final mirror 15, a dew condensation state detection optical sensor 17 for detecting the dew condensation state of the final mirror 15 according to the degree of fogging of the final mirror 15 is arranged. As the dew condensation state detecting optical sensor 17, for example, a photodiode is used.

FIG. 3 is a block circuit diagram showing the electrical configuration of the dehumidification controller. Reference numeral 17 is the above-mentioned optical sensor for detecting the dew condensation state, 18 is an amplifier circuit, 19 is an A / D converter, 20
Is a CPU (Central Processing Unit) that controls the entire system, 21 is a ROM (Read Only Memory) that stores a program for the control, and 22 is a RAM (which stores the data while assisting the control. (Random access memory), 3 is the above operation panel, 23 is a dehumidifying driver, 24 is a switching circuit composed of a relay or a triac, 25 is a dehumidifying device composed of a resistance heating element, and 26 is a commercial power supply of 100 V AC. is there.

FIG. 4 shows the arrangement of the dehumidifier 25. A
The symbols E to E show the positions where the dehumidifier 25 is arranged. It is located in the cassette section, optical unit section, transport section, process section, and so on. The dehumidifying device 25 is a resistance heating element that generates a dry amount of heat, and mainly includes a high-power cement resistor, a low-power heating lamp, and a sheet-shaped resistor. Exchange 1
When the commercial power source 26 of 00V is turned on, the self-heat is generated, and the amount of heat (the temperature of the resistance heating element itself is about 100 ° C.) convects to stabilize the internal temperature of the machine and exert the dehumidifying effect.

Next, the operation of the dehumidification control device will be described with a focus on the flowchart of FIG. The dehumidification mode is set by a service person or the like pressing a specific key (simulation) on the operation panel 3. At the time of installation of the copying machine, when the destination is relatively humid and it is necessary to perform dehumidification control, the service person usually sets the dehumidification mode. When the destination is a dry zone and dehumidification control is not required first, dehumidification mode is not set. The setting / non-setting of the dehumidifying mode is stored in the RAM 22. This RA
The contents of M22 are retained even when the main power supply is turned off.

When the power is turned on while the power is off, the operation from step S1 is started. Step S
At 1, it is determined whether the dehumidification mode is set.
If not set, the process proceeds to step S2 to set the copy ready state, and in this state, waits for the copy key to be pressed in step S3, and when it is pressed, step S4
Proceed to the following to make a normal copy.

However, it is assumed here that the dehumidification mode is set. Therefore, from step S1 to step S
Proceed to step 5 to perform machine initials such as scanning the mirror. Next, in step S6, the copy lamp 11 is temporarily operated (2 to 3 seconds). The exposure light emitted from the copy lamp 11 is the front stage mirror 1 of the optical unit section 10.
2, the lens 13, the rear stage mirror 14 and the final mirror 1
Up to 5. Then, a part of the light reflected by the final mirror 15 reaches the dew condensation state detection optical sensor 17. The dew condensation state detection optical sensor 17 generates a current according to the amount of received light, which is amplified by the amplification circuit 18 and converted into digital data by the A / D converter 19 to generate CP.
It is sent to U20. The CPU 20 compares the reflected light amount detection level L _i input in step S7 with the reference level A ₀ stored in advance in the ROM 21. If dew condensation occurs inside the copying machine while the power is off, the final mirror 15 also becomes cloudy, and the amount of light reflected by the final mirror 15 also decreases. The higher the cloudiness of the final mirror 15,
The reflected light amount detection level L _i by the dew condensation state detection optical sensor 17 also becomes low.

The reflected light amount detection level L _i is the reference level A _0.
In the following cases, since the copy ready state cannot be achieved, the process proceeds to step S8, the dehumidifying driver 23 is driven to turn on the switching circuit 24, and the dehumidifying device 25 is energized to dehumidify the inside of the copying machine. Although not shown in the flow chart, in parallel with the operation of the dehumidifier 25, a message "dehumidifying" is displayed on the display unit of the operation panel 3 to inform the user of that fact, and the heat lamp Energize and warm up.

Then, the process proceeds to step S9 to start the timer counter, waits until the predetermined count value N is reached at step S10, and then proceeds to step S10 to turn off the switching circuit 24 and stop the dehumidifying device 25. Further, the process returns to step S6 to temporarily operate the copy lamp 11, and the reflected light amount detection level L _i is determined in step S7. Until the reflected light amount detection level L _i exceeds the reference level A ₀ , the operation panel 3
Even if the copy key is operated, the copy operation is not performed (copy prohibition state), and the occurrence of copy with poor image quality is prevented. Then, the dehumidifier 25 is turned on to continue dehumidification.

As a result of such repetition, the reflected light amount detection level L _i will eventually exceed the reference level A ₀ , and the process will proceed from step S7 to step S2 to become the copy ready state. In the copy ready state, waiting for the copy key to be pressed in step S3, step S4
Go to and make a normal copy. In this copy operation, since dehumidification is completed, it is possible to make a copy in a good image quality state.

As described above, the dehumidifying mode is set at the destination where the dew condensation may occur, so that the dehumidifying device can be performed only when the optical unit 10 is fogged due to the dew condensation while the power is off. 25 is driven, and the dehumidifying device 25 is not driven when it is not necessary, so wasteful power consumption can be suppressed. By dehumidifying the dehumidification mode at the destination where there is no possibility of dew condensation, it is possible to prohibit the dehumidification operation while the power is off and eliminate unnecessary power consumption.

Second Embodiment FIG. 6 is a dew condensation removing characteristic diagram showing the relationship between the reflected light amount detection level L _i and the required dehumidifying time T _i . When the amount of dew condensation is small, the amount of fog is small, and the reflected light amount detection level L _i is large, but at this time, the dehumidification time may be short (for example, L ₁
And T ₁ ). On the contrary, when the amount of dew condensation is large and the amount of fog is large, the reflected light amount detection level becomes small, but in this case, the dehumidification time needs to be long (for example, L _n and T _n ). Data corresponding to this characteristic condition is stored in the ROM 21 in advance. Other configurations are the same as those in the first embodiment (see FIGS. 2, 3 and 4). CPU2 is different
The control operation is 0.

The operation will be described below with reference to the flowchart of FIG. The operation contents from step S1 to step S6 are the same as in the first embodiment. After temporarily operating the copy lamp 11 in step S6,
In step 20, it is determined whether or not the reflected light amount detection level L _i is less than the reference level α, and if it is equal to or higher than the reference level α, it is determined that there is no cloudiness, and the process proceeds to the copy ready state in step S2. If it is less than the reference level α, the process proceeds to step S21, where R is set based on the reflected light amount detection level L _i.
Accesses the OM21, reads the data of the dehumidifying time T _i corresponding to the level L _i, store the dehumidifying time T _i in step S22 in the register N (N ← T _i). next,
In step S23, the dehumidifying device 25 is driven to dehumidify the inside of the copying machine. When the dehumidifying device 25 is driven, a message "dehumidifying" is displayed on the display of the operation panel 3, and the heat lamp is energized to warm up. Then, the process proceeds to step S24 to start the timer counter, waits for reaching a predetermined count value N (contents of register N) in step S25, and then proceeds to step S26 to stop the dehumidifying device 25. As a result, the inside of the copying machine can be dehumidified in a dehumidifying time that appropriately corresponds to the degree of dew condensation.

After step S26, the process proceeds to the copy ready state of step S2, waits for the copy key being pressed in step S3, and then proceeds to step S4 to perform normal copying. In this copy operation, since the dehumidification is completed, the image quality of the copy is good. Also in this embodiment, since the dehumidifying device 25 is driven only when the optical unit 10 is fogged and the dehumidifying device 25 is not driven when it is not necessary, wasteful power consumption can be suppressed.

Third Embodiment As shown in FIG. 8, in the optical unit section 10, an exposure sensor 27 is arranged on the lateral side of the lens 13. The exposure sensor 27 is for detecting the lightness and darkness of a document during a copying operation, and is an optical sensor 17 for detecting the dew condensation state of cloudy weather.
It is also used for detecting the light amount of the reference exposure light when reading. As the exposure sensor 27, for example, a photodiode is used. As shown in the block circuit diagram of FIG. 9, a dew condensation state detection optical sensor 17
Is connected to the A / D converter 19 via the amplifier circuit 18, the exposure sensor 27 is also connected to the A / D converter 19 via the amplifier circuit 28, and each digital data is individually supplied to the CPU 20. It will be sent out.

Compared to the reference light amount detection level L ₀ by the exposure sensor 27, the reflected light amount detection level L _i by the dew condensation state detection optical sensor 17 for detecting the light reflected by the final mirror 15 through the lens 13 and the rear stage mirror 14. Is smaller. Especially if there is cloudiness due to dew condensation.
FIG. 10 is a dew condensation characteristic diagram showing the relationship between the difference ΔL _i (= L ₀ −L _i ) between the reference light amount detection level L ₀ and the reflected light amount detection level L _i and the required dehumidification time T _i . When the amount of dew condensation is small and the amount of fog is small, the detection level difference ΔL _i is small and the dehumidification time T _i may be short (for example, ΔL ₁ and T
₁ ). On the contrary, when the amount of dew condensation is large and the detection level difference ΔL _i becomes large, the dehumidification time T _i also needs to be long (for example, ΔL _n and T _n ). Data corresponding to this characteristic condition is stored in the ROM 21 in advance.

The operation will be described with reference to the flowchart shown in FIG. The operation contents from step S1 to step S6 are the same as those in the first and second embodiments. After temporarily operating the copy lamp 11 in step S6, the flow advances to step S30 to input the reference light amount detection level L ₀ by the exposure sensor 27, and in step S31 the reflected light amount detection level L by the dew condensation state detection optical sensor 17. _i is input, and the detection level difference ΔL _i (= L
₀ −L _i ) is calculated. Then, in step S33, it is determined whether or not the detection level difference ΔL _i is equal to or greater than the reference value β, and if it is less than the reference value β, it is determined that there is no cloudiness, and the process proceeds to the copy ready state in step S2. Reference value β
Or more of time, accesses the ROM21 based on the detected level difference [Delta] L _i proceeds to step S34, the detection level difference [Delta] L _i reads data of the dehumidifying time T _i corresponding to, the dehumidification time T _i register in a step S35 Store in N (N ← T _i ). Next, in step S36, the dehumidifying device 25 is driven to dehumidify the inside of the copying machine. When the dehumidifying device 25 is driven, a message "dehumidifying" is displayed on the display of the operation panel 3, and the heat lamp is energized to warm up. Then, in step S37, the timer counter is started,
In step S38, after waiting for the predetermined count value N (content of the register N) to be reached, the process proceeds to step S39, and the dehumidifying device 25 is stopped. As a result, the inside of the copying machine can be dehumidified in a dehumidifying time that appropriately corresponds to the degree of dew condensation.

After step S39, the process proceeds to the copy ready state in step S2, waits for the copy key to be pressed in step S3, and proceeds to step S4 to perform normal copying. In this copy operation, since the dehumidification is completed, the image quality of the copy is good. Also in this embodiment, since the dehumidifying device 25 is driven only when the optical unit 10 is fogged and the dehumidifying device 25 is not driven when it is not necessary, wasteful power consumption can be suppressed.

Fourth Embodiment FIG. 12 shows a block circuit diagram of the dehumidification control device. In the figure, 31 is a copy lamp driver controlled by a copy lamp control signal CLC from the CPU 20, 32 is a photocoupler, and 33 is pulse width modulation (PW).
M) Control circuit, 34 is a fuse, and 36 is a solid state relay. The solid state relay 36 includes a light emitting diode 37, a photothyristor 38, a triac 39, a surge voltage absorbing absorber 40 including a resistor and a capacitor, and the like. Reference numeral 41 is a lamp noise removing coil, 26 is a commercial power supply of 100 V AC, and 11 is a copy lamp.

FIG. 13 shows the AE characteristic (exposure characteristic) with respect to the light and shade of the original. The higher the gain, the smaller the change in the applied voltage V _CL to the copy lamp 11 with respect to the change in shading. On the other hand, FIG. 14 shows the exposure amount correction characteristic. The horizontal axis represents the difference ΔL _i (= L ₀ −L _i ) between the reference light amount detection level L ₀ and the reflected light amount detection level L _i, and the vertical axis represents the AE characteristic gain. When used for a long period of time, dirt is attached to the mirrors 12 and 14 of the optical unit 10 and the lens 13 due to dust or dust. Contamination of the optical system consequently shifts the exposure of the white background of the document to the dark side. Therefore, if the amount of exposure light is kept as it is, the copy image quality becomes defective. The difference ΔL _i between the reference light amount detection level L ₀ by the exposure sensor 27 and the reflected light amount detection level L _i by the dew condensation state detection optical sensor 17 after the dehumidification is completed should correspond to dirt. .

Therefore, as shown in FIG. 14, the exposure gain is increased as the degree of contamination increases and the detection level difference ΔL _i increases. This exposure amount correction characteristic data is stored in the ROM 21 in the same manner as the dew condensation removal characteristic data in FIG.
Stored in advance.

That is, in this embodiment, the detection level difference Δ
As the control after dehumidification based on L _i , the dirt of the optical system is detected based on the detection level difference ΔL _i at regular intervals, and the exposure correction is performed according to the detected dirt level. It was done.

In this case, the detection level difference ΔL _i used for dehumidification and the detection level difference ΔL used for exposure correction.
_The same exposure sensor 27 and dew condensation state detecting optical sensor 17 are also used as _i .

The operation will be described with reference to the flow charts of FIGS. When the power is turned on from the power off state, the operation from step S41 is started. In step S41, it is determined whether the dehumidification mode is set. If not set, the process skips to step S54 (copy ready state), but here, the dehumidification mode is set. Therefore, the process proceeds from step S41 to step S42 and machine initials such as scanning the mirror are performed, and the copy lamp 11 is temporarily operated in step S43 (2 to 3 seconds). The exposure light emitted from the copy lamp 11 passes through the front stage mirror 12, the lens 13, and the rear stage mirror 14 of the optical unit section 10 to reach the final mirror 15. Then, a part of the light reflected by the final mirror 15 reaches the dew condensation state detection optical sensor 17. The dew condensation state detection optical sensor 17 generates a current according to the amount of received light, which is amplified by the amplification circuit 18 to generate A /
It is converted into digital data by the D converter 19 and sent to the CPU 20. CPU20, step S
44, the reference light amount detection level L ₀ by the exposure sensor 27 is input, the reflected light amount detection level L _i by the condensation state detection optical sensor 17 is input in step S45, and the detection level difference ΔL _i (= L ₀ −L _i ) is calculated. Then, in step S47, the detection level difference ΔL
It is determined whether _i is greater than or equal to the reference value β, and if it is less than the reference value β, it is determined that there is no cloudiness, and step S
Skip to 54 (copy ready state). If it is equal to or greater than the reference value β, the process proceeds to step S48 and the detection level difference Δ
The ROM 21 is accessed based on L _i , the data of the dehumidification time T _i corresponding to the detection level difference ΔL _i is read,
In step S49, the dehumidifying time T _i is stored in the register N (N ← T _i ). Next, in step S50, the dehumidifying device 25 is driven to dehumidify the inside of the copying machine.

When the dehumidifying device 25 is driven, a message "dehumidifying" is displayed on the display section of the operation panel 3,
Also, the heat lamp is energized to warm up. Then, in step S51, the timer counter is started, and in step S52, a predetermined count value N
Wait until (contents of register N) is reached at step S5
3, the dehumidifying device 25 is stopped. As a result, the inside of the copying machine can be dehumidified in a dehumidifying time that appropriately corresponds to the degree of dew condensation.

After step S53, the process proceeds to the copy ready state in step S54, and then in step S55, it is determined whether the count value of the number of copies from the latest maintenance has reached a predetermined value C or not. If the predetermined value C has not been reached yet, the process proceeds to step S56 to wait for the copy key to be pressed, and if it has been pressed, step S57.
Proceed to the following to make a normal copy.

When the count value of the number of copies after the maintenance reaches the predetermined value C, the process proceeds to step S58 to set the exposure amount correction mode. When this mode is set, the exposure correction is performed before the mirror scan every time the copy key is pressed every day or every time a predetermined number of copies are made. That is, after the copy key is pressed in step S59, the process proceeds to step S60, the copy lamp 11 is temporarily operated again, the reference light amount detection level L ₀ by the exposure sensor 27 is input in step S61, and in step S62. Detection level L _{i of} reflected light amount by the optical sensor 17 for detecting the dew condensation state
Is input, and the detection level difference ΔL _i (=
Calculate L ₀ −L _i ). Detection level difference Δ at this time
L _i is after completion of dehumidification, and is due to the dirt of the optical unit section 10 due to dust or dust. Then, by accessing the ROM21 based on the detected level difference [Delta] L _i in step S64, reads the data of the exposure gain K _i corresponding to the detected level difference [Delta] L _i from exposure correction characteristic data, stored in the register K in the step S65 ( K ← K _i ). Then, in step S66, the copy lamp control signal CL is generated corresponding to the exposure gain K _i.
C is generated and the pulse width in the pulse width modulation control circuit 33 is adjusted. The control signal of the pulse width is given from the CPU 20 to the pulse width modulation control circuit 33 via the copy lamp driver 31 and the photocoupler 32. Next, a mirror scan is performed in step S67, and a copy operation is started in step S68.

The light emitting diode 37 is timing-controlled according to the output waveform from the pulse width modulation control circuit 33 and blinks, the photothyristor 38, which is a zero voltage switch element, is turned on at the time of lighting, and the triac 39 is also turned on. The triac 39 turns off when the commercial power supply 26 is near zero volts. The conduction angle of the triac 39 is determined by the pulse width of the pulse width modulation control circuit 33. In addition to the above-mentioned exposure gain K _i , the pulse width and hence the conduction angle are determined by the exposure sensor 2 during mirror scanning.
The light amount detection level from 7 is determined as a factor. With such phase control, the copy lamp 11 is energized while the triac 39 is conducting. In this copy operation, dehumidification is completed, and the adverse effect of dirt on the optical system is corrected, so that it is possible to make a copy in an appropriate image quality state. The difference ΔL _i between the reference light amount detection level L ₀ and the reflected light amount detection level L _i for determining the cloudy state due to dew condensation is also taken as the detection level difference ΔL _i for determining the contamination of the optical system. Also, the same exposure sensor 27 and dew condensation state detection optical sensor 17 are used.
Since this is also used, the configuration is simplified and the cost is also advantageous.

The fifth embodiment is structurally similar to the fourth embodiment (see FIGS. 12-14). The operation will be described with reference to the flowcharts of FIGS. Before step S41 of the fourth embodiment, it is determined in step S40 whether or not the control mode is set.
When installing a copying machine in a wetland or an area where temperature changes drastically, the service person usually sets the dehumidification mode as a simulation input. Dehumidification mode is not set in dry areas. In addition, the exposure amount correction mode may or may not be set depending on the period elapsed from the start of installation or the total number of copies. If it is determined in step S40 that no control mode is set, step S40
Proceed to step a and perform normal copying. When set,
Proceeding to step S41, the dehumidifying operation is executed as in the fourth embodiment.

After the copy ready state in step S54, it is determined in step S54a whether or not the exposure amount correction mode is set. If not set, the process proceeds to normal copying in step S40a and the setting is made. If so, the exposure amount correction operation is executed as in the fourth embodiment.

As described above, since the service person can appropriately set / cancel the control mode according to the situation such as the region and the season, it is possible to efficiently operate the copying machine with less waste.

[0047]

According to the dehumidifying controller of the first to third copying machines of the present invention, the dehumidifying operation is performed only when dew condensation occurs, and the dehumidifying time is in the dew condensation state. Therefore, it is possible to make a copy in a good image quality state while preventing unnecessary power consumption.

Further, according to the dehumidification control device in the fourth copying machine of the present invention, the exposure amount correction for removing the influence of stains after the dehumidification is completed, even when the detection level difference which is the basis of the dehumidification operation is obtained. Since the common exposure sensor and the dew condensation state detecting optical sensor are used also to obtain the detection level difference that is the basis of the above, it is possible to simplify the configuration and reduce the cost.

[Brief description of drawings]

FIG. 1 is a perspective view showing an appearance of a copying machine common to first to fifth embodiments of the present invention.

FIG. 2 is a cross-sectional view showing an outline of an optical unit section in the copying machine according to the first and second embodiments.

FIG. 3 is a block circuit diagram showing an electrical configuration of a dehumidification control device according to the first embodiment and the second embodiment.

FIG. 4 is a cross-sectional view showing an arrangement state of a dehumidifier common to the first to fifth embodiments.

FIG. 5 is a flowchart for explaining the operation of the dehumidification control device according to the first embodiment.

FIG. 6 is a dew condensation removal characteristic diagram showing a relationship between a reflected light amount detection level and a necessary dehumidifying time according to the second embodiment.

FIG. 7 is a flowchart for explaining the operation of the dehumidification control device according to the second embodiment.

FIG. 8 is a cross-sectional view schematically showing an optical unit section common to the third to fifth embodiments.

FIG. 9 is a block circuit diagram showing an electrical configuration of a dehumidification control device according to a third embodiment.

FIG. 10 is a dew condensation characteristic diagram showing the relationship between the dehumidification time and the difference between the reference light amount detection level and the reflected light amount detection level that are common to the third to fifth embodiments.

FIG. 11 is a flowchart for explaining the operation of the dehumidification control device according to the third embodiment.

FIG. 12 is a block circuit diagram showing an electrical configuration of a dehumidification control device common to the fourth and fifth embodiments.

FIG. 13 is an AE characteristic diagram according to the fourth and fifth examples.

FIG. 14 is an exposure amount correction characteristic diagram according to the fourth and fifth examples.

FIG. 15 is a flowchart for explaining the operation of the dehumidification control device according to the fourth embodiment.

FIG. 16 is a flowchart for explaining the operation of the dehumidification control device according to the fourth embodiment.

FIG. 17 is a flowchart for explaining the operation of the dehumidification control device according to the fourth embodiment.

FIG. 18 is a flowchart for explaining the operation of the dehumidification control device according to the fifth example.

FIG. 19 is a flowchart for explaining the operation of the dehumidification control device according to the fifth example.

FIG. 20 is a flowchart for explaining the operation of the dehumidification control device according to the fifth embodiment.

[Explanation of symbols]

10 Optical Unit Section 11 Copy Lamp 12 Front Mirror 13 Lens 14 Rear Mirror 15 Final Mirror 16 Photosensitive Drum 17 Optical Sensor for Dew Condensation Detection 20 CPU 21 ROM 23 Dehumidification Driver 24 Switching Circuit 25 Dehumidifier 27 Exposure Sensor 33 Pulse Width Modulation Control Circuit 36 Solid State Relay L ₀ Reference Light Level Detection Level L _i Reflected Light Level Detection Level ΔL _i Detection Level Difference T _i Dehumidification Time

Claims (4)

[Claims] 1. An optical sensor for detecting a condensation state, which is arranged in the optical unit section in the vicinity of a final mirror immediately before a photosensitive drum, a unit for temporarily operating a copy lamp at the time of machine initializing when a power source is turned on, and the copy lamp. Means for detecting a part of the exposure light that has been irradiated and reflected from the final mirror through the optical unit through the optical sensor for detecting the condensation state; and means for comparing the reflected light amount detection level with a predetermined value. , A means for shifting to a copy ready state when the reflected light amount detection level is larger than a predetermined value, and a copy prohibition state when the reflected light amount detection level is smaller than a predetermined value and operating the dehumidifier to set the reflected light amount detection level to a predetermined value. Repeat the temporary operation of the copy lamp and the dehumidifying device until it becomes larger than the specified value, and make it larger than the specified value. A dehumidification control device in a copying machine, characterized in that the dehumidification control device comprises means for shifting to a copy ready state. 2. A dew condensation state detecting optical sensor arranged in the optical unit section in the vicinity of a final mirror immediately before a photosensitive drum, and data of dew condensation releasing characteristics indicating a relationship between a reflected light amount detection level and a dehumidifying time are stored in advance. Means and power on
Means for temporarily operating the copy lamp at the time of the machine initializing, and a part of the exposure light emitted from the copy lamp and reflected from the final mirror through the optical unit section by the dew condensation state detecting optical sensor. Means for comparing the reflected light amount detection level with a predetermined value, means for shifting to a copy ready state when the reflected light amount detection level is larger than a predetermined value, and the reflected light amount detection level is lower than a predetermined value. When it is also small, a copy prohibition state is set, a dehumidification time corresponding to the reflected light amount detection level is read from the storage means, the dehumidification device is operated over the dehumidification time, and a means for shifting to the copy ready state after the dehumidification time elapses. A dehumidification control device for a copying machine, comprising: 3. An exposure sensor arranged near the lens in the optical unit section, a dew condensation state detection optical sensor arranged near the final mirror in the optical unit section immediately before the photosensitive drum, and a reference light amount detection level by the exposure sensor. And means for preliminarily storing the data of the dew condensation release characteristic showing the relationship between the dehumidification time and the difference between the detection level of the amount of light reflected from the final mirror by the dew condensation state detection optical sensor, and a copy at the time of machine initial when the power is turned on. Means for temporarily operating the lamp, means for detecting a part of the exposure light emitted from the copy lamp via the exposure sensor, and exposure light reflected from the final mirror through the optical unit section. Means for detecting a part of the light through the optical sensor for detecting the condensation state, and the reference light amount detection level and the condensation state by the exposure sensors. Means for calculating the difference between the detection level of the reflected light amount by the state detection optical sensor, means for comparing the detection level difference with a reference value, and means for shifting to the copy ready state when the detection level difference is smaller than the reference value When the detection level difference is larger than a reference value, a copy prohibition state is set, a dehumidification time corresponding to the detection level difference is read from the storage unit, and a dehumidification device is operated over the dehumidification time. A dehumidification control device in a copying machine, comprising: a unit that shifts to a copy ready state after a lapse of time. 4. An exposure sensor arranged near the lens in the optical unit section, a dew condensation state detecting optical sensor arranged near the final mirror in front of the photosensitive drum in the optical unit section, and a reference light amount detection level by the exposure sensor. And means for pre-storing data of the dew condensation characteristic showing the relationship between the dehumidification time and the difference between the detection level of the amount of light reflected from the final mirror by the dew condensation state detection optical sensor, the detection level difference and the exposure gain. Means for pre-storing the data of the exposure amount correction characteristic showing the relationship of, the means for temporarily operating the copy lamp at the time of machine initializing when the power is turned on, and a part of the exposure light emitted from the copy lamp. Means for detecting via the exposure sensor and a part of the exposure light reflected from the final mirror through the optical unit section are combined. Means for detecting through the dew-state detecting optical sensor, means for calculating the difference between the reference light amount detection level by the exposure sensor and the reflected light amount detecting level by the dew-condensation state detecting optical sensor, and the detection level difference as a reference value And a means for shifting to a copy ready state when the detection level difference is smaller than a reference value, and a copy prohibition state when the detection level difference is larger than the reference value, and the detection level from the storage means. A means for operating the dehumidifying device for reading the dehumidifying time according to the difference and operating the dehumidifying device for the dehumidifying time, a means for shifting to the copy ready state after the dehumidifying time elapses, and with the operation of the copy key from the copy ready state, again Temporary operation of copy lamp, detection of reference light amount detection level and reflected light amount detection level, detection level Means for performing a minute calculation, dehumidifying control device in the copying machine, characterized in that a means for exposure control reads the exposure gain corresponding to the detected level difference.