JPS6050566A - Electrophotographic copying device - Google Patents

Abstract

PURPOSE:To prevent trouble such as ignition, etc., and to shorten a waiting time for restart by controlling a heat roller fixing device to a lower temperature than a regular fixing temperature never to cut off a heat source when a paper jam is generated. CONSTITUTION:When a paper jam detecting circuit 33 detects the paper jam, a paper jam generating display is executed on an operating panel 32 by a paper jam generating signal (d), and also a paper jam state signal (e) is outputted to a power saving control circuit 36. The control circuit 36 outputs a power saving state signal (c) to a temperature control circuit 35, and by a temperature control signal (f), a fixing device 34 is temperature controlled so as to obtain the temperature lower than a regular fixing temperature by about 25 deg.C. Accordingly, when processing the paper jam, the trouble such as smoking, ignition, etc. are eliminated, and also since the heat source is not cut off, a re-waiting time for restart can be shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrophotographic copying apparatus in which the temperature of a heat roll fixing device is controlled to be low when a paper jam occurs.

[Prior art and its problems]

Conventionally, paper jammed inside devices such as copying machines, especially paper jammed near the fixing device, is handled by controlling the fixing device at the same fixing temperature as during copying or normal standby without turning off the heat source. There was a risk of smoke or ignition caused by the heat source. To prevent this, when a paper jam occurs, the power to the heat source of the heat roll fixing device is cut off, but in this case, the disadvantage is that the temperature of the fixing device drops after the paper jam has been cleared, resulting in a longer waiting time. was there.

[Purpose of the invention]

The present invention has been made in consideration of the above points, and an object of the present invention is to provide an electrophotographic copying apparatus that controls the surface temperature of the heat roller of a heat roll fixing device to be kept lower than the normal temperature when a paper jam occurs. do.

〔Example〕

In order to achieve the above object, the present invention includes a means for indicating a paper jam and a power saving control circuit that controls the heat roller fixing device to a temperature lower than the normal fixing temperature when a paper jam occurs. This is to ensure that the heat source is not cut off.

This invention will be explained below with reference to the drawings.

FIG. 1 is a sectional view of a copying apparatus to which the present invention is applied.

The structure and operation will be explained below.

Original 21:6 An original (not shown) placed on the glass 1L is illuminated by an illumination lamp 3 that is integrated with the first scanning mirror 2, and the reflected light is transmitted to the first scanning mirror 2 and the second scanning mirror 2.
It is scanned by a scanning mirror 4. The first scanning mirror 2 and the second scanning mirror 4 are driven at a speed ratio of 1:1/2. Therefore, the original is scanned while the optical path length in front of the zoom lens 5 is always kept constant. Reference numeral 6 denotes a photosensitive drum which is rotated in the direction of the arrow by a motor number not shown.

After passing through the zoom lens 5 and the third mirror 7, the reflected light image is formed on the photosensitive drum 6 at the exposure section. Note that 8 is a blank exposure lamp.

The photosensitive drum 6 is uniformly charged by a negative charger 9, and an electrostatic latent image is formed thereon by image exposure. The electrostatic latent image on the photosensitive drum 6 is then developed by a developing roller 11 of a developing device 10 and visualized as a toner image, and the toner image is transferred to a transfer paper by a transfer charger 12. The transfer paper in the cassette 13 is fed into the machine by a paper feed roller 14, and is fed in the direction of the photosensitive drum 6 by a register roller 15 with accurate timing. At this time, the leading edge of the latent image and the leading edge of the transfer paper are aligned at the transfer section. In the transfer section, a transfer charger 12 performs corona discharge from behind the transfer paper to electrostatically transfer the toner onto the transfer paper. Next, an AC corona or a separation charger 16 having a polarity opposite to that of the transfer charger 12 neutralizes the electric charge on the back surface of the transfer paper, and separates the transfer paper from the photosensitive drum 6.
8 and transported. After the transfer paper has been separated, the photosensitive drum 6 is neutralized by a pre-cleaner static eliminator 17, and then untransferred toner remaining on the photosensitive drum 6 is removed from the surface of the photosensitive drum 6 by a cleaner 19. on the other hand,
The transfer paper passes through a fuser 2° and the toner image is permanently fixed thereon. Note that 21 is a fixing roller, and 22 is a temperature sensor.

FIG. 2 is a block diagram showing a schematic configuration of an embodiment of the present invention. In this figure, 31 is a power saving switch which, together with a timer, is used to save power in the apparatus after copying is completed. Reference numeral 32 indicates an operation panel that indicates the status of the system, 33 indicates a paper jam detection circuit, 34 indicates a fixing device having a heat source, 35 indicates a temperature control circuit that controls the temperature of the fixing device 34, and 36 indicates the paper jam detection circuit 33. This is a power-saving control circuit that outputs a power-saving command for the fixing device 34 to the temperature control control circuit 35 based on a detected paper jam, where a indicates an ON/OFF signal for the power-saving switch 31, and b indicates an operation panel to which the power-saving control circuit 36 outputs. 32
, C is the power saving state signal outputted by the power saving control circuit 36, and d is the power saving state signal outputted from the operation panel 3 when the paper jam occurs.
2 is a paper jam occurrence signal, e is a paper jam state signal outputted from the paper jam generation circuit 33 to the power saving control circuit 36, f is
is a temperature control signal outputted from the temperature control circuit 35. The operation will be explained below.

ON/OFF signal "' when power saving switch 31 is ON
At this time, the power saving control circuit 36 sends a power OFF signal to the operation panel 32 and outputs a power saving state signal C. Based on this power saving state signal C, the temperature control circuit 35 adjusts the temperature of the fuser 34 to the power saving temperature. Here, the fixing device 34
The surface temperature of the fixing roller is detected by a contact type thermistor, and in the power saving state, the fixing roller surface temperature is approximately 160℃,
The temperature control circuit 35 controls the surface temperature of the fixing roller of the fixing device 34 so as to maintain the temperature at about 185° C. except in the fM power state.

Next, we will discuss control when a paper jam occurs.

When the paper jam detection circuit 33 detects a paper jam, a paper jam occurrence signal d is used to display a paper jam occurrence indication on the operation panel 32, and at the same time, a paper jam status signal e is sent to put the fixing unit 34 into a power saving state. Output.

Here, paper jam detection is performed by paper jam resensors (not shown) in each part provided at predetermined locations in the main body, and a paper jam occurrence signal d
The drive of the main body stops at the same time as this occurs. Further, the power saving control circuit 36 outputs only the power saving state signal C to the temperature control circuit 35, and the fixing device 34 is put into the power saving state by the temperature control signal f, and the temperature is adjusted to be about 25° C. lower than the normal state. Note that the reason why only the power saving state signal C is outputted is to prevent the power saving control circuit 36 from outputting the OFF signal to the operation panel 32 from becoming unable to grasp the temperature control occurrence state.

〔Effect of the invention〕

As described above, the present invention not only displays the occurrence of a paper jam, but also maintains the heat source temperature of the fuser lower than the normal temperature from the time the operator recognizes the occurrence of the paper jam until the paper jam clearing process is completed. To prevent trouble caused by
Since the waiting time until the restart after clearing a paper jam can be shortened, there are advantages such as efficient operation.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a copying apparatus to which the present invention is applied, and FIG. 2 is a block diagram showing a schematic configuration of an embodiment of the present invention. In the figure, 31 is a power saving switch, 32 is an operation panel, 33 is a paper jam detection circuit, 34 is a fixing device, 35 is a temperature control circuit,
36 is a power saving control circuit, a is an ON-OFF signal, b is a power OFF signal, C is a power saving state signal, d is a paper jam occurrence signal,
e is a paper jam state signal, and f is a temperature control signal.

Claims (1)

[Claims] In an electrophotographic copying apparatus that controls the temperature of a heat roller fixing device, means for displaying the occurrence of a paper jam of paper fed to the electrophotographic copying device; An electrophotographic copying apparatus characterized by comprising a power saving control circuit that controls the temperature to a lower temperature than that of the electrophotographic copying apparatus.