JPH02163786A - image forming device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] (Summary) This invention relates to an image forming apparatus that can cumulatively count the time during which the heat roller of the heat fixing device is heated to a predetermined temperature or higher. The purpose of the present invention is to provide an image forming device that develops an electrostatic image formed on an image forming body with toner,
An image forming apparatus that transfers an image onto a medium and fixes the image by applying heat and pressure using a heat fixing device equipped with a heat roller whose outer periphery is lined with a resin material having elasticity and heat resistance. energization control means that starts energizing the heat roller when the temperature of the troller is below the lower limit temperature and stops energization when the temperature reaches the upper limit; temperature detecting means for detecting that the temperature is above the predetermined time; time setting means for presetting a predetermined time; and time counting means for cumulatively counting the time during which a predetermined temperature or higher is detected up to a predetermined time. When the time reaches a predetermined time, it is configured to notify that the predetermined time has been reached.

[Industrial application field]

The present invention relates to an image forming apparatus including a heat fixing device such as an electrophotographic printing device, and more particularly to an image forming device capable of cumulatively counting the time during which a heat roller of the heat fixing device is heated to a predetermined temperature or higher. It is something.

Heat rollers used in heat fixing devices such as electrophotographic printing equipment are lined with an elastic and heat-resistant resin material such as silicone rubber to improve fixing performance, but the lining layer gradually deteriorates due to heating. Since this leads to deterioration of image quality, etc., it is necessary to replace it, and there is a need for a method that can easily determine when it is time to replace it due to its lifespan.

[Conventional technology]

FIG. 4 illustrates an internal side view of the electrophotographic printing apparatus. In the figure, reference numeral 1 indicates an optical unit 2, which is a photosensitive drum, 3, a static eliminator, 4, a cleaner, 5, a charger, 6, a developing device, 7, a transfer section Ja, a fixing device, and 9, a transport path.

The fixing device 8a includes an upper limit temperature sensor S1 for controlling the temperatures of the fixing roller R1, the pressure roller R2, and the fixing roller R1.
and lower limit temperature sensor S2 (hereinafter referred to as temperature sensor Sl, S
2), an oil supply mechanism (not shown) that applies silicone oil to the roller, and a cleaning member (not shown) that cleans the roller.

As shown in FIG. 5, the fixing roller R1 includes a hollow metal roller 11 whose outer periphery is lined with a resin material 9 having elasticity and heat resistance, such as silicone rubber 12a, and a heater lamp 13 built into the hollow part. .

The pressure roller R2 has silicone rubber 1 on the metal roller 14.
5 is lined. Fixing roller I? 1 is connected to a motor (not shown). Also, temperature sensor St,
S2. The heater lamp 13 is connected to a control section (not shown).

With such a configuration, when the power of the device is turned on, the temperature sensor S2 reaches a predetermined lower limit temperature (for example, 16()).
°C) or less is detected and the heater lamp 13 is energized,
When the fixing roller R1 is heated and reaches the lower limit temperature, it becomes ready for printing. Furthermore, a predetermined upper limit temperature (e.g. 180°C
), the temperature sensor S1 detects this and stops energizing, and when the temperature decreases and reaches the lower limit temperature, the temperature sensor S2 detects and starts energizing, and from then on the temperature range (
For example, the temperature is controlled at 160 to 180°C.

Then, based on the print instruction signal, the printing paper 10 is fed out from a cassette (not shown) in the direction of arrow A, conveyed along the conveyance path 9, and sent below the photosensitive drum 2. By this time, the photosensitive drum 2 has been neutralized by the static eliminating section 3, cleaned by the cleaner 4, and charged again by the charging section 5.

Therefore, optical data converted by an optical unit 1 composed of a laser light source or the like is irradiated onto a photosensitive drum 2. The electrostatic image formed on the photosensitive drum 2 is developed into a toner image in a developing section 6, transferred to a printing paper 10 in a transfer section 7, and then sandwiched between a fixing roller R1 and a pressure roller R2 in a fixing device 8a. The toner is heated and pressurized, fixed, and discharged.

When the device is powered off, the heater lamp 13 is also de-energized.

Although printing is performed in this manner, the fixing roller R1 is always heated to a fixing temperature while the power is on, and since the fixing temperature is high, the silicone rubber 12a on the outer periphery gradually deteriorates.

As the deterioration progresses, not only the outer peripheral surface becomes rough and the fixing performance deteriorates, but also the rubber layer expands and the outer diameter of the fixing roller R1 changes, so the feeding speed of the printing paper 10 changes and Fixing roller R with the end in transfer section 7
If the feeding rate of 1 is increased, a shift occurs in the transfer and the image quality deteriorates. Furthermore, in the worst case, wrinkles occur in the printing paper 10. Therefore, the image quality of the fixing roller I21 is monitored and replaced when the limit is determined.

(Problems to be Solved by the Invention) According to the above conventional method, the lifespan of the silicone rubber lining the outer periphery of the fixing roller is determined by looking at the state of deterioration in image quality, but the criterion is subjective and varies from person to person. Moreover, since the replacement is required after the image quality has deteriorated, there is a problem in that it is difficult to prevent the image quality from deteriorating beforehand.

SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus in which it is possible to easily know when to replace the heat roller of the heat fixing device due to its lifespan.

[Means to solve the problem]

FIG. 1 is a block diagram of the principle of the present invention.

In the figure, 80 is a heat roller whose outer periphery is lined with a resin material 12 having elasticity and heat resistance, 8 is a heat fixing device equipped with the heat roller 80, and 16 is a heat roller 80 of the heat fixing device 8 whose temperature is below the lower limit temperature. An energization control means starts energizing the heat roller 80 and stops energization when the upper limit temperature is reached; 19 indicates that the temperature of the heat roller 80 to which energization is started and stopped by the energization control means 16 is at a predetermined temperature or higher; 17 is a time setting means in which a predetermined time is set in advance; 18 is a cumulative count of the time during which a predetermined temperature or higher is detected by the temperature detection means 19 up to a predetermined time set in the time setting means 17; This is a time counting means.

Here, the predetermined temperature is set as the lowest temperature at which the resin material 12 lining the outer periphery of the heat roller 80 begins to deteriorate.

Therefore, when the cumulative time counted by the time counting means 18 reaches the predetermined time set in the time setting means 17,
It is configured to notify that a predetermined time has been reached.

[Effect]

The time setting means 17 sets a predetermined time, that is, the heat roller 80
The energization time indicating the time to replace the fuser 8 is set in advance, and when the power is turned on, the energization 11111 means 16 connects to the heat fixing unit 8.
energization is started to the heat roller 80 when the temperature of the heat roller 80 is below the lower limit temperature, and when the temperature of the heat roller 80 reaches a predetermined temperature or higher, the temperature detection means 19 detects the temperature and the time counting means 18 starts counting, When the heat roller 80 reaches the upper limit temperature, the energization is stopped, but if the temperature is above a predetermined temperature, the time counting means 18 continues counting, and when the temperature falls below the predetermined temperature, the detection by the temperature detecting means 19 is canceled and the time is counted. The counting means 18 stops counting. Further, when the temperature of the heat roller 80 falls below the lower limit temperature, the energization control means 16 starts energization again, and the heat roller 80 is heated. Thus, regardless of whether or not the heat roller 80 is energized, if the temperature of the heat roller 80 is higher than the predetermined temperature, the temperature detection means 19 continues to detect the temperature, and the time setting means 18 cumulatively counts the time.

In this way, the time during which the heat port 80 is at a predetermined temperature or higher is cumulatively counted, and when the predetermined time set in the time setting means 17 is reached, it is notified that the predetermined time has been reached. Therefore, it is possible to easily know when to replace the heat roller 80.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 2 and 3. The same reference numerals refer to the same objects throughout the design.

In FIG. 2, parts corresponding to those in FIG. 1 are shown surrounded by a dashed line.

FIG. 2 shows a block diagram of a fixing device to which the present invention is applied to the electrophotographic printing apparatus described in the conventional example.

In the figure, the energization control unit 16a starts energizing the heater lamp 13 of the fixing roller R1 when the temperature of the fixing roller R1 of the fixing device 8a is below the lower limit temperature, notifies the appropriate fixing temperature by detecting the temperature of the temperature sensor S1, and When the temperature reaches the temperature, the power supply is stopped by detection by the temperature sensor S2.

In the setting section 17a, a set time T0 is preset as the energization time indicating the time to replace the fixing roller R1.

The sensor S3 is provided in the fixing device 8a and is connected to the heater lamp 1.
This sensor detects that the temperature No. 3 is higher than a predetermined temperature. Here, the predetermined temperature is the lowest temperature at which deterioration of the silicone rubber 12a lining the outer periphery of the fixing roller R1 progresses, and the predetermined temperature may be less than the lower limit temperature or higher than the lower limit temperature, but here, it is within the printing temperature range. within, i.e.
The lower limit temperature 1 (e.g. 160°C) and the upper limit temperature (e.g. 18
The following description will be made assuming that there is a predetermined temperature (for example, 170°C) between 0°C and 0°C.

The timer 18a is the heater lamp 13 of the fixing roller R1.
Counting the time during which the sensor S3 detects the temperature of
Counting is stopped when sensor S3 releases detection. The counting time is accumulated until the set time T0 is counted.
It is not cleared regardless of N10FF, that is, the power is turned off.
Counting time is supported even in FF mode. Then, it is reset by replacing the fixing roller R1.

The comparison unit 20 compares the set time T0 set in the setting unit 17a.
and the cumulative counting time T counted by the timer 18a to determine the magnitude relationship. When the cumulative counting time ↑1 reaches the set time T0 (T+=To), an alarm signal is sent.

The notification control section 21 turns on the alarm lamp L based on the alarm signal sent from the comparison section 20.

Further, 22 indicates a main control section.

Since it has such a configuration and function, the operation will be explained with reference to the flowchart in FIG. 3.

■Turn on the device power.

(2) Then, the temperature sensor S2 detects a temperature below the lower limit temperature of the fixing roller R1, and the energization control section 16a sends an energization signal a to energize the heater lamp 13.

(2) When the temperature of the fixing roller R1 rises and the temperature sensor S2 detects the lower limit temperature, a notification is given and the printing becomes possible and printing is performed.

(2) When the temperature further rises and the temperature sensor S3 detects a predetermined temperature, the timer 18a is activated to count the temperature detection continuation time.

■When the fixing roller R1 reaches the upper limit temperature, the temperature sensor S
1 is detected, the energization control unit 16 stops the energization signal a,
The heater lamp 13 is de-energized.

(2) When the temperature of the fixing roller R1 falls below a predetermined temperature and detection by the temperature sensor S3 is canceled, the timer 18a stops counting.

(2) When the temperature further decreases and the temperature sensor s2 detects the lower limit temperature, the energization signal a is sent again and the heater lamp 13 is energized. The flow from ■ onwards is repeated.

■Eventually, printing is completed and the device power is turned off, and then ■
The subsequent flow is repeated until the predetermined time T0 is counted.

■When the comparator 20 determines that the cumulative counting time of the timer 18a has reached the predetermined time T, an alarm signal is emitted, and the alarm lamp L is controlled by the notification controller 21.
lights up.

[Phase] Then, the power of the apparatus is turned off and the fixing roller R1 is replaced. Then, timer I8a is reset.

The above operation is performed under the control of the main/sub j8 section 22.

In this way, it is possible to accurately know when to replace the fixing roller R1 due to its lifespan, so that deterioration in image quality and occurrence of wrinkles in the paper can be prevented, and the reliability of the apparatus can be improved.

In the above example, we explained the case where the predetermined temperature is set between the lower limit temperature and the upper limit temperature of the printing temperature range, but this depends on the heat resistance characteristics of silicone rubber, and it may be set almost close to the lower limit temperature or below the lower limit temperature. In some cases. When the temperature is close to the lower limit temperature, the temperature sensor S3 becomes unnecessary, and the lower limit temperature is detected by the temperature sensor S2 to notify that printing is possible, and the timer is controlled to start counting time.

〔Effect of the invention〕

As explained above, according to the present invention, the time that the heat roller is heated to a predetermined temperature or higher can be cumulatively counted up to the set time by the time counting means, so that it is possible to accurately determine when to replace the heat roller based on its lifespan. This has the effect of preventing deterioration in image quality and wrinkles in printing paper, thereby increasing the reliability of the apparatus.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the principle of the present invention, Fig. 2 is a block diagram showing an embodiment of the invention, Fig. 3 is a flowchart of the embodiment, Fig. 4 is an internal side view of an electrophotographic printing device, and Fig. 5 FIG. 2 is a configuration diagram of a fixing roller. In the figure, 8 is a heat fixing device, 8a is a fixing device, 12 is a resin material,
12a and 15 are silicone rubber, 16 is energization control means, 16a is energization control section, 17 is time setting means, 17a is setting section, I8 is time counting means,
18a is a timer 19, a temperature detection means; 80 is a heat roller; R1 is a fixing roller; R2 is a pressure roller; and S1 to S3 are temperature sensors. ! ! (ζshinkomen new i (i), i □91men mouthshiba, ni-ra f)4. Figure 'f, 5f3

Claims (1)

[Claims] Developing an electrostatic image formed on an image forming body with toner,
An image forming device that transfers an image onto a medium and fixes the image by heating and applying pressure using a heat fixing device (8) equipped with a heat roller (80) whose outer periphery is lined with an elastic and heat-resistant resin material (12). There is an energization control means (16) that starts energizing the heat roller (80) of the heat fixing device (8) when the temperature of the heat roller (80) is below the lower limit temperature, and stops energizing the heat roller (80) when the temperature reaches the upper limit temperature. ), temperature detection means (19) for detecting that the temperature of the heat roller (80) whose energization is started and stopped by the energization control means (16) is higher than a predetermined temperature, A time setting means (17), and a time counting means (18) for cumulatively counting the time during which the temperature is detected to be above the predetermined temperature by the temperature detecting means (19) up to a predetermined time set in the time setting means (17). and when the cumulative time counted by the time counting means (18) reaches a predetermined time set in the time setting means (17), a notification is given that the predetermined time has been reached. image forming device.