JPS6184661A - Device for preventing paper jam in copying machine - Google Patents

Abstract

PURPOSE:To discharge the copying paper in a copying machine to the outside of the machine and to prevent fire, etc. by providing a backup power source for emergency in the copying machine body and driving a conveying mechanism for a prescribed period by the power supplied from said backup power source when the power supply from an outside power source is interrupted. CONSTITUTION:The supply electric power from the outside power source 1 and the inside power source such as storage battery enters a control circuit 3 and the output from the circuit 3 is inputted to a motor 4 for driving a conveying system. The electric power for driving a motor 4 is supplied via the circuit 3. The circuit 3 has the function to convert the current and voltage of the outside power source 1 and the inside power source 2 to the current and voltage suitable for driving of the motor 4 and the function to control whether the electric power for driving the motor 4 is to be supplied from the power source 1 or the power source 2. The copying paper existing in the machine is discharged to the outside of the machine by the power supply from the power source 2 when the power supply from the power source 1 is interrupted owing to a certain cause during copying.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a paper jam prevention device for a copying machine.

(Prior Art) In conventional copying machines, if the power supply from the external power source is cut off due to stopping during copying or being accidentally unplugged, the drive of the transport mechanism stops and the copy paper is cut off. remains on the conveyance system, even if the power supply from the external power supply is resumed, the paper jam detection means will detect the paper jam and the conveyance mechanism will stop operating, making it difficult to take steps such as removing the paper. Unless this is done, each device within the copier will not warm up or become ready for copying. As a method of dealing with the above-mentioned copy paper remaining on the conveyance system,
As disclosed in specifications such as Publication No. 4-125649,
2. Description of the Related Art A copying apparatus has been proposed in which, when the copying machine main body is powered on, a conveyance mechanism is driven for a certain period of time to eject copy paper remaining on a conveyance system.

(Problems to be Solved by the Invention) Conventional copying machines such as the former have a problem in that handling paper jams is complicated and requires time and effort. In addition, with the latter type of copying machine, if a long time elapses after the power supply from the external power source is cut off until the power supply is resumed next time, copy paper may remain in the machine during that time, resulting in paper jams. There are problems such as deformation of the detection switch, and there is also a risk of the copy paper catching fire if it remains in relatively high temperature parts of the machine (for example, the fixing section), which poses safety problems.

(Means for solving the problems) The present invention was made to solve the above problems, and
The first aspect of the present invention is that an emergency bank-up power supply is installed in the main body of the copying machine, so that even if the power supply from the external power supply is cut off for some reason while each device of the copying machine is operating, power is immediately supplied from the backup power supply. By driving the conveyance mechanism for a predetermined period of time, the copy paper present in the conveyance mechanism is ejected to the outside of the machine.

In the second aspect of the present invention, when the power supply from the external power supply is cut off, the presence or absence of copy paper is detected in the conveying mechanism by a means for detecting the presence or not, and a predetermined value is determined based on the copy paper presence signal from the detection means. This is driven by a time-shifting mechanism.

(Function) In a normal copying state, the drive motor 4 for driving the transport mechanism is driven by the power supplied from the external power supply 1, but when each device of the copying machine is in operation, power is not supplied from the external AT. When the power is cut off, power is immediately supplied from the internal power supply 2, and the drive motor 1 is driven for a predetermined period of time to eject the copy paper present in the transport mechanism. At this time, the drive motor 4 is driven for a predetermined period of time based on a copy paper presence signal from a detection means for detecting the presence of copy paper within the conveyance mechanism.

(Example) The present invention will be explained using specific examples. FIG. 3 schematically shows the conveyance mechanism of the copying machine main body 20, and copy paper is conveyed as follows.

That is, the copy paper 21 in the paper feed cassette 22 is fed by the paper feed roller 23 between the guide plates 24 and 25 to the registration roller 26, and is further fed to the registration roller 26 in connection with exposure scanning by an optical system (not shown). Drive and guide plate 2
After 7.28 seconds, it is sent to the transfer section. The toner image formed on the photosensitive drum 29 is transferred to the copy paper 21 sent to the transfer section by a transfer charger 30, and then the copy paper 21 is separated from the photoconductor drum 29 by a separation charger 31.

The separated copy paper 21 is conveyed to a fixing section 33 by a conveying belt 32, thermally fixed by the fixing section 33, and then discharged onto a discharge tray 35 by a discharge roller 34.

In FIG. 1 showing a circuit for controlling the transport mechanism of the copying machine described above, power supplied from an external power supply 1 and power supplied from an internal power supply 2 such as a storage battery are supplied to a control circuit 3.
is input. The output from the control circuit 3 is input to the transport system drive motor 4, and electric power for driving the motor 4 is supplied via the control circuit 3. Although not shown, the control circuit 3 includes a mechanism that detects information such as a normal state or a paper jam and controls the operation of each device of the copying machine based on the information, as well as a conventional well-known circuit. In addition to the display mechanism, there is also a function to convert the current and voltage of the external power supply l and internal power supply 2 to be suitable for driving the motor 4, and by detecting device information, the power for driving the motor 4 can be converted to the external power supply. It has a function to control whether to supply power from the internal power supply 1, from the internal power supply 2, or to stop the power supply.

In addition, when the internal power source 2 is a storage battery, if the voltage of the storage battery decreases due to discharge or consumption, a part of the power supplied from the external power source can be supplied to charge the storage battery. shall exist.

The operation of the control circuit 3 will be explained in detail based on the flowchart shown in the second figure.Power for driving the motor 4 is supplied from the external power source 1 in the normal copying state of 5 steps. 5te
In step ■, the normal copying state is repeated as long as the power supply from the external type ti, ■ continues, but if the power supply is interrupted, the process moves to 5 step ■, and the copy paper is transferred to the conveyance mechanism inside the copying machine main body. It is determined whether there is a paper jam (paper jam or not).

If there is no copy paper in the transport mechanism, 5 steps ■
The process moves to step 2, and the power supply to the motor 4 is stopped, but if there is copy paper, the process moves to step 5, where power is supplied from the internal power source 2 to drive the motor 4. At 5tep■-,
If a paper jam occurs while the motor 4 is being driven by the internal power source 2, the process moves to 5 step (2) and the motor 4 is stopped; if no paper jam occurs, the process moves to 5 step (□). 5tep ■
Then, it is determined whether or not the power supply from the internal power supply 2 exceeds a predetermined time. If the predetermined time has not been exceeded, the process returns to step 5 and repeats the operation. If the time has exceeded, the process moves to step 5 and the power supply is stopped. At this time, the predetermined time is at least the time required for the maximum size copy paper to be conveyed from the registration rollers 26 to the carry-out rollers 34 and to be discharged onto the discharge tray 35.

In the above embodiment, it has been explained that the transport mechanism is driven by the internal type [2], but it is also possible to use the internal power supply 2 not only for the transport mechanism but also for the operation of a solenoid, etc., the display on the display, etc. It is.

(Effects of the Invention) As detailed above, the present invention provides that even if the power supply from the external power supply is cut off for some reason during copying, the copy paper present in the transport mechanism is ejected to the outside of the copying machine. As soon as electricity is restored and the tag is warmed up or ready for copying, it also eliminates the risk of copying paper remaining in high-temperature areas such as the fuser and causing a fire, which is extremely effective in terms of safety. .

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the electrical configuration of the present invention, FIG. 2 is a flowchart showing the control operation of the embodiment, and FIG. 3 is a schematic diagram of the conveyance mechanism of the main body of the copying machine. 1... External power supply 2... Internal power supply 3... Control circuit 4... Drive mode, ri 20... Copying machine main body

Claims (3)

[Claims] (1) External power supply means for supplying power into the copying machine main body;
In addition to having an internal power supply means provided inside the copying machine main body,
When driving at least the transport mechanism of the copying machine main body,
It has a power supply switching means for selecting and switching between supplying power from an external power supply or an internal power supply, and simultaneously switches to supplying power from the internal power supply when the power supply from the external power supply is cut off during copying, and transports for a predetermined time. A paper jam prevention device for a copying machine, characterized in that the mechanism is driven. (2) external power supply means for supplying power into the copying machine body;
In addition to having an internal power supply means provided inside the copying machine main body,
When driving at least the transport mechanism of the copying machine main body,
It has a power supply switching means for selecting and switching between supplying power from an external power supply or an internal power supply, and also switches to supplying power from the internal power supply at the same time as the power supply from the external power supply is cut off during copying. In this case, the transport mechanism includes a detection means for detecting whether or not copy paper is present in the transport mechanism, and a drive means for driving the transport mechanism for a predetermined period of time based on a copy paper presence signal from the detection means. Features: Paper jam prevention device for copying machines. (3) Based on the copy paper presence signal from the detection means,
A copying machine according to claim 2, characterized in that the conveyance mechanism is driven for a predetermined time and the drive of the conveyance mechanism is stopped in response to a copy paper jam signal that occurs during the predetermined time. Paper jam prevention device.