JPH02116575A - Sheet feeder in image forming device - Google Patents

Abstract

PURPOSE:To reduce a labor for paper-jamming processing by a method wherein paper feed information is stored in a nonvolatile memory, an error indication and a paper discharge action are changed over according to a paper feed state when a power supply is rethrown after being cut during a paper feed action, and a device is reset. CONSTITUTION:In a microcomputer serving as a control means 43, detection signals and others from a paper feed sensor 41 and a paper discharge sensor 42 are inputted, and a motor 45 for driving a paper feed roller 28 and others through a driver 44 and a pressure developing device 18 are connected. A nonvolatile memory 46 is provided for the control means 43 to sequentially write and store therein the detection signals from the sensors 41, 42 and data representing a paper feed state according to a sheet feed amount or time. On the basis of the data in the nonvolatile memory 46, the control means 43 judges the state of color developing paper 26 at the time of the rethrowing of a power supply after the power interruption during a paper feed action. If the paper is disposed in an upstream area of a feed path just after the start of paper feeding, an error indication is displayed on a display panel; if the paper reaches an downstream area of the feed path after a time elapses after the paper feed, a paper discharge action is conducted.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a sheet conveying device in an image forming apparatus such as a copying machine or a printer, and more specifically, the present invention relates to a sheet conveying device in an image forming apparatus such as a copying machine or a printer. This invention relates to improvement of the recovery processing procedure when the power is turned on again.

[Prior Art] Conventionally, in copying machines and the like, when the power is turned off during paper feeding operation and the power is turned on again, the sheet is in the conveyance path and becomes a paper jam, and the user has to remove the sheet. It was necessary to remove it.

[Problems to be Solved by the Invention] However, for example, in a copying machine having a pressure developing device, it is difficult to open the sheet conveyance path around the pressure developing device, so it is difficult to clear a jam in the vicinity. was quite complicated.

Another possibility is to eject paper for a predetermined period of time whenever the power is turned on again, but this would prevent paper feeding errors from occurring at the most upstream side of the conveyance path, that is, at the paper feeding section. In this case, paper jams are likely to occur again, and relatively expensive photosensitive and pressure-sensitive paper is also rolled up and wasted unnecessarily, which is inconvenient.

The present invention has been made to solve the above-mentioned problems, and by sequentially storing the paper feeding status in a non-volatile memory, paper jams that occur when the power is turned off during paper feeding can be avoided. On the other hand, when the power is turned on again, error display and paper ejection operation are automatically selected depending on the paper feeding status.
An object of the present invention is to provide a sheet conveyance device in an image forming apparatus that can reduce the burden on a user.

[Means for Solving the Problem] In order to achieve this object, the present invention provides an exposing means for exposing a recording medium, a developing means for developing the recording medium on which an exposed latent image is formed, and a developing means for developing the recording medium on which an exposed latent image is formed. In a sheet conveying device in an image forming apparatus, which is equipped with a sheet feeding means for conveying a sheet and a control means for controlling the driving thereof, the sheet conveying device is provided on the upstream side and downstream side of the developing device in the sheet conveying direction. The control device includes a paper feed sensor and a paper discharge sensor provided respectively, and a nonvolatile memory that sequentially stores detection signals from these sensors and paper feeding information based on the conveyance amount of the sheet. When the power is turned on again after being turned off, the paper feed sensor is turned on based on the information in the memory, and if the sheet conveyance is less than a predetermined value, an error message is displayed, and at least the paper feed sensor or paper ejection sensor is turned on. If any one of these is on and the sheet is being conveyed by a predetermined amount or more, the ejecting operation is performed.

[Function] According to the above configuration, sheet position information is sequentially stored in the nonvolatile memory during sheet feeding operation, and the leading edge of the sheet is positioned upstream of a predetermined image recording process means facing the sheet conveyance path, for example, a fixing device. The error display or paper ejecting operation is appropriately selected depending on whether the paper is on the side or the downstream side.

[Embodiment] FIG. 1 shows a schematic configuration of a light- and pressure-sensitive copying machine capable of full-color copying according to an embodiment of the present invention. The photosensitive paper made of microcapsule paper and developer paper used in the copying machine of this embodiment has been proposed in Japanese Patent Application Laid-Open No. 58-88739, and will not be described in detail here.

The photosensitive and pressure sensitive copying machine 1 is composed of an original platen glass 2 and an original platen cover 3, the top plate of which is movable in the left and right directions.
A desired original is set face down on the original platen glass 2.

A light source consisting of a halogen lamp 4 extending in a direction perpendicular to the direction of movement of the document platen glass 2 and a semi-cylindrical reflecting mirror 5 arranged so as to surround it is disposed on the upper right side of the copy 1fi1. Light is irradiated in a line toward the document table glass 2. Therefore, the light emitted from the halogen lamp 4 sequentially illuminates the entire surface of the document table glass 2 from the left end to the right end by moving the document table glass 2 in the left-right direction. The light emitted from the light source passes through the transparent document table glass 2 and is reflected by the document placed thereon, thereby exposing and scanning the document. Note that the upper surface of the document table glass 2 is covered with a document table cover 3 so that the irradiated light does not leak from parts other than the document.

In addition, in order to use the light emitted from the halogen rung 4 to irradiate the original with high efficiency, a beam flap 6 is placed to the left of the light source to reflect the light that does not go directly to the original and use it again to irradiate the original. . A fan 7 and a louver 8 are provided on the right side of the halogen lamp 4 to draw air from the outside.
This allows cooling air to be applied to the document table glass 2 efficiently.

Light emitted from the halogen lamp 4 and reflected from the document placed on the document table glass 2 passes through the filter 9 and enters the lens 10 . This filter 9 is for adjusting the color tone of the copied image, and is provided in the optical path so that it can be inserted and removed freely.
The light transmission characteristics are changed and controlled according to the sensitivity characteristics of the microcapsule paper 11. The lens 10 is attached to a lens mounting plate 12, and allows minute angle adjustment to the optical path.

The light focused by the lens 10 passes through a pair of reflective mirrors 13
．． 13, the direction is changed by 180°, and an image is formed on the microcapsule paper 11 closely placed below the exposure table 14.

The reflecting mirrors 13.13 are mounted on a mirror mounting plate 15, and by finely adjusting the mounting position of the mirror mounting plate 15, the optical path length and focus are adjusted.

On the other hand, a long microcapsule paper 11 is wound around a cartridge shaft 16 and housed in a removable cartridge 17 placed below the document table glass 2. and a pressure developing device 18 before reaching one winding shaft. That is, the microcapsule paper 11 coming out from the lower part of the curl ridge 17 is transferred to the feed roller 20, tie roller 21, and nip roller 21.
- After passing under the exposure table 14, it is supplied to the pressure developing device 18. The microcapsule paper 11 that has passed through the pressure developing device 18 is guided by a peeling roller 22 and a meandering adjustment roller 23, and then wound onto one winding shaft. Note that the unexposed microcapsule paper 11 after leaving the cartridge 17 is maintained in an unexposed state by the light shielding cover 24.

The transport speed of the microcapsule paper 11 is controlled to be constant by the capsule paper feed roller 25, and is made to match the moving speed of the document platen glass 2, so that the microcapsule paper 11 is Latent images of predetermined lines of the document are sequentially formed.

Further, a side colored paper cassette 27 is provided below the pressure developing device 18 for storing side colored paper sheets 26 of a cassette paper type, and the color developing paper 26 is taken out one by one by a half-moon-shaped paper feed roller 28 and is then developed. After the leading end is aligned by the colored paper roller 29 and the registration gate 30, the paper is conveyed to the paper entrance of the pressure developing device 18.

In this manner, the microcapsule paper 11 and the color developing paper 26 are supplied to the pressure phenomenon device 18 in a state in which they are in close contact with each other and are integrated. The pressure developing device 18 is composed of a small diameter roller 31 and a back unroller 32. The microcapsule surface of the microcapsule paper 11 on which the latent image has been formed and the developer-coated surface of the color developer paper 26 are brought into contact with each other on the inside, and are sandwiched between the small diameter roller 31 and the backup roller 32 and subjected to pressure. Added. This pressure destroys the unexposed microcapsules and forms an image on the colored paper 26. The pressure developing device 18 and the heat fixing device 33 (described later) constitute a process means for forming an image.

The microcapsule paper 11 and color developer paper 26 that have come out of the pressure developing device 18 are conveyed by a capsule paper feed roller 25.
The microcapsule paper 11 and the color developing paper 26 are separated by the peeling roller 22 . After the coloring of the top colored paper 26 is promoted by the heat fixing device 33 and an image is formed, the top colored paper 26 is transferred to the paper output tray 34.
It is transported with the image side up. The heat fixing device 33 includes a hollow heat roller 37 having a heater 35 and a temperature sensor 36 therein, and a developing paper feed roller 38. The blown microcapsule paper 11 passes through a meandering adjustment roller 23 and is wound around a winding shaft 19.

Also, facing the conveyance path of the color developer paper 26, a pressure phenomenon device 1 is provided.
A paper feed sensor 41 is arranged on the upstream side of 8 in the paper conveyance direction, and a paper discharge sensor 42 is arranged on the downstream side immediately after the thermal fixing device 33. Furthermore, in connection with the copying operation of the copying machine, a control means 43 is provided for controlling the feeding of the colored paper 26 and turning on and off the roller pressure of the pressure developing device 18.

The peripheral structure of this control means 43 will be explained with reference to FIG. 2. The control means 43 is composed of a microcomputer, into which detection signals from the paper feed sensor 11 and the paper ejection sensor 42 are input, and which also receives signals for driving the paper feed roller 28 and the like via a driver 44. A motor 45 and a pressure developing device 18 are connected thereto. Furthermore, a non-volatile memory (RAM) 46 in which the control means 43 sequentially writes and stores detection signals from the sensors 41 and 42 and data indicating the sheet feeding state according to the sheet conveyance amount or time.
is equipped with.

Then, based on the data in the non-volatile memory 46, the control means 43 determines the state in which the color developing paper is when the power is turned off and then turned on again during the paper feeding operation.
The details will be described later, but immediately after the start of paper feeding and when the paper is in the upstream area of the conveyance path, an error message will be displayed on the display panel (not shown).
When the paper has reached the downstream area of the conveyance path after a period of time has elapsed from paper feeding, it has a function of performing a paper ejection operation.

In the above configuration, the operation thereof will be explained below.

Now, after opening the document cover 3 and placing the document on the document glass 2, press the exposure start switch (not shown). Stops at the position where the left end faces the light source. after that,
The document table crow 2 is moved to the left while the halogen lamp 4 is lit. The light emitted from the halogen lamp 4 is reflected by the original, and then passes through the filter 9 and the lens 1.
0 and a pair of reflective mirrors 13.13,
An image is formed on the microcapsule 11 located below the exposure table 14. At this time, the microcapsule paper 11 is moved to the left on the exposure table 14 at the same speed as the moving speed of the document table glass 2, so the image on the document is formed as a latent image on the microcapsule paper 11. be done.

As the document platen glass 2 moves to the left, the paper feed roller 2
The color developer paper 26 is taken out from the color developer paper cassette 27 by 8, and is supplied to the pressure developing device 18 in a superimposed state with the exposed microcapsule paper 11, so that the latent image on the microcapsule paper 11 has a color ratio of m. The image is then transferred onto developer paper 26. Thereafter, the developing paper 26 is thermally fixed by the thermal fixing device 33 and then discharged outside the copying machine 1 . On the other hand, the microcapsule paper 11 that has passed through the pressure developing device 18 is sequentially wound onto the winding shaft 19. When the right end of the document platen glass 2 finishes moving to a position facing the light source, copying of the document is completed and the halogen lamp 4 is turned off.

Next, see the third section about the paper feeding process and the recovery process when the power is turned on again.
This will be explained with reference to the timing chart shown in the figure. In the figure, the horizontal axis is the time axis, and here, the period A is between the paper feed start time t1 and the on time t2 of the paper feed sensor 41, and the time between the time t2 and the tip of the color developer paper 26 or the heat roller 37 is defined as a period A. The period between the arrival time t5 is defined as a period B, the period between the time t5 and the ON time of the paper discharge sensor 42 is defined as a period C, and the period between the time t6 and the OFF time t8 of the paper discharge sensor 42 is defined as a period.

During period A, skew correction is performed by the resist gate 30, and during period B, the leading edge of the color developer paper 26 is exposed to the pressure developing device 1.
The conveyance of the color developing paper 26 is stopped between the time 3 when the developing paper 26 reaches the position 8 and the time t4 when the pressure developing device 18 is closed (pressure is applied). The transport length between time t4 and time t5 is approximately 100ITlff1 in a general copying machine. During this process, separation of the color developing paper 26 and the capsule paper 11 is started. Also, normally, the paper feed sensor 41 is turned off during the period.
The time t7 comes.

The processing mode for each period when the power is turned on again is as follows.

Period A: Return to normal state. However, it is possible that a paper jam may occur during the next copying operation.

Period B: While the paper feed sensor 41 is ON, a paper jam is displayed, and when the cassette 27 is pulled out and the paper is taken out, the paper feed sensor 41 is turned OFF and the normal state is restored.

Period C: Paper ejection operation is performed. Once, the specified amount, 1
If the paper ejection sensor 42 is not ONL even after general feeding, it is determined as an error. Note that if the paper feed sensor 41 is OFF before the ejecting operation, the normal state is assumed and the paper feed sensor 41 is returned to the normal state. This is power OFF
This is because it is determined that the jammed paper F has been removed.

Period D=paper ejection operation is performed. However, if the discharge sensor 42 does not reach 0FFL even after the paper has been conveyed by a predetermined amount, it is determined as an error. Note that if both the paper feed sensor 41 and the paper discharge sensor 42 are OFF before the ejection operation, the normal state is restored.

The judgment as to which of the above periods the paper feeding state is in when the power is turned on again is determined based on the data stored in the non-volatile memory 46 and shown in Table 1 below, according to the flowchart shown in FIG. Just follow the steps shown.

In the flowchart of FIG. 4, for example, [00] means data at address [00] of the nonvolatile memory. Then, the data at address [OO] and address [01] are compared, and if they are different, it is determined that it is period A (step Sl, 32).

If the data at address [00] and address [01] are the same,
Next, compare the data at addresses [01] and [02] and if they are different, it is determined that it is period B (steps S3 and S4).
. Thereafter, the period CD is determined in the same way (step 3
5. S6. S7).

Note that the data at each address in the initial state does not need to be "00" and may be rFFJ.

In addition, even in the initial state, if the paper ejection sensor 42 is ON, the paper ejection operation is performed, so the period and the initial state can be considered to be the same. sensor 4
2 is shown, but multiple pieces,
It may be used. In addition, the non-volatile memory 46
may be a normal RAM backed up by a battery or the like.

[Effects of the Invention] As described above, according to the present invention, paper feeding information is sequentially stored in a nonvolatile memory, and when the power is turned off and then turned on again during paper feeding operation, the paper feeding state is restored. Accordingly, the error display or paper ejecting operation is switched as appropriate to restore the machine, which reduces the burden on the user in handling paper jams and reduces the possibility of paper jams occurring again when the power is turned on again. In addition, effects such as eliminating unnecessary paper ejection and wasteful consumption can be obtained.

(Hereafter, margin)

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional configuration diagram of an image forming apparatus according to an embodiment of the present invention, FIG. 2 is a configuration diagram around a control means of the apparatus,
FIG. 3 is a time chart showing the control processing mode, and FIG. 4 is a flow chart for determining the paper feeding state. 4...Halogen lamp, 11...Micro capsule paper, 18...Pressure developing device, 26...M colored paper, 27
... Developing paper cassette, 28... Paper feed roller, 41.
... Paper feed sensor, 42 ... Paper discharge sensor, 43 ... Control means, 46 ... Nonvolatile memory. Applicant: Brother Industries, Ltd.

Claims (1)

[Scope of Claims] An exposing means for exposing a recording medium, a developing means for developing the recording medium on which an exposed latent image is formed, and a paper feeding means for conveying a sheet for making the latent image visible. and a control means for controlling the drive of the sheet conveying device in the image forming apparatus, a sheet feeding sensor and a sheet discharging sensor respectively provided upstream and downstream of the developing device in the sheet conveying direction;
The control device includes a non-volatile memory that sequentially stores paper feeding information based on detection signals from these sensors and the conveyance amount of the sheet, and when the power is turned on again after being turned off during paper feeding operation, the control device Based on the information of In the above case, the sheet conveyance device in the image forming apparatus is characterized in that it performs a sheet ejection operation.