JP2001166646A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device constituted so that trouble is prevented from occurring when the size of recording paper set by a user and the size of actually supplied recording paper are mutually different. SOLUTION: This image forming device is provided with a resist roller on which the leading edge of the supplied recording paper P abuts and which holds and carries the paper P to an image carrier 10 in timing that it coincides with a toner image on the carrier 10, a resist sensor 25 arranged near the upstream side of the resist roller so as to detect the trailing edge of the paper P carried to the carrier 10 by the resist roller, a display part 121 displaying a message to the user and a control part 500 deciding the size of the supplied paper P based on time until the trailing edge of the paper P is detected by the sensor 25 after the resist roller is driven at the image forming time of a 1st sheet, stopping the driving of the device and displaying the message at the display part 121 in the case where the detected size is different from the size of the recording paper set by the user.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for setting the size of a recording paper by a user, forming a toner image on an image carrier,
The present invention relates to an image forming apparatus for transferring the toner image onto recording paper.

[0002]

2. Description of the Related Art In an image forming apparatus for forming a toner image on an image carrier and transferring the toner image onto a recording sheet, a user of a low-cost image forming apparatus sets the size of the recording sheet. .

[0003]

However, when the size of the recording paper set by the user is different from the size of the recording paper actually supplied to the apparatus, there are the following problems.

(1) For example, when a user sets A3 recording paper and an A4 recording paper smaller in size than the A3 recording paper is actually supplied, the entire toner image formed on the image carrier is recorded. Not transferred to paper.

(2) For example, when the user sets A4 recording paper and the A3 recording paper that is longer than the A4 recording paper in the transport direction of the recording paper is actually supplied, the jam detecting device operates. Then, the device stops.

(3) The recording paper onto which the toner image has been transferred is conveyed to the fixing means, passes between a heating roller and a pressure roller, and the toner image is thermally fixed on the recording paper. The temperature control of the heating roller of the fixing unit is performed according to the size of the recording paper set by the user. When the user sets a narrow recording sheet, such as A4, and fixes a plurality of sheets continuously, the non-sheet passing of the heating roller is performed to prevent the temperature of the non-sheet passing portion of the heating roller from rising. The non-sheet passing section is cooled by blowing air to the section.

However, when the size of the recording paper set by the user is different from the size of the recording paper actually supplied, for example, when the user sets the A3 recording paper, the A3 recording paper is actually set. If a narrower A4 paper is supplied,
Since the control to cool the non-sheet passing portion of the heating roller by blowing air is not performed, the temperature of the non-sheet passing portion of the heating roller becomes abnormally high, the thermostat operates, and further operation of the device is prohibited. It becomes a state.

Conversely, if the user sets A4 recording paper and, in fact, A3 recording paper that is wider than A4 recording paper is supplied, the wind hits a part of the heating roller and the wind hits it. In some cases, the part cooled by cooling may be under-fixed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to solve the problem (toner) when the size of the recording paper set by the user is different from the size of the actually supplied recording paper. The entire image is not transferred to the recording paper, the jam detection device operates, the device stops, the thermostat operates, further operation of the device is prohibited, and under-fixing etc. is prevented. To provide.

[0010]

According to the first aspect of the present invention, a user sets a size of recording paper,
In an image forming apparatus that forms a toner image on an image carrier and transfers the toner image onto the recording paper, the size of the supplied recording paper is determined, and the size is different from the size of the transfer paper set by the user. And an image forming apparatus characterized by stopping the apparatus.

The size of the supplied recording paper is determined. If the size of the recording paper is different from the size of the transfer paper set by the user, the apparatus is stopped to stop the recording paper size set by the user and the size of the actually supplied recording paper. Trouble when the size of the recording paper is different (the entire toner image is not transferred to the recording paper. The jam detection device operates, the device stops. The thermostat operates, and further operation of the device is prohibited. , Etc.).

According to a second aspect of the present invention, in the first aspect of the present invention, the leading end of the supplied recording paper comes into contact with the recording paper and the image recording medium is held at a timing coincident with the toner image on the image carrier. A registration roller that is nipped and conveyed to the body, a registration sensor that is provided near the upstream of the registration roller, and detects a rear end of the recording paper conveyed to the image carrier by the registration roller, and sends a message to a user. The size of the supplied recording paper is determined from the display unit to be displayed and the time from when the registration roller is driven to when the registration sensor detects the rear end of the recording paper when the first sheet of image is formed. And a control unit for stopping the driving of the apparatus when the recording paper size is different from the size set by the user and displaying a message on the display unit. An image forming apparatus.

The control unit detects the time from when the registration roller is driven to when the registration sensor detects the trailing edge of the recording sheet when the first image is formed. If the size is different from the recording paper size set by the user, the device stops driving and displays a message on the display unit,
Trouble when the size of the recording paper set by the user and the size of the actually supplied recording paper are different (the entire toner image is not transferred to the recording paper. The jam detection device operates and the device stops. The thermostat Operates, and further operation of the apparatus is prohibited. Under-fixing, etc.) can be prevented.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to the drawings. First, the overall configuration and operation will be described with reference to FIG. 2 showing the overall configuration of an image forming apparatus according to an embodiment of the present invention.

In FIG. 1, an image forming apparatus 1 includes an automatic document feeder (ADF) A and a document image reading unit B for reading an image of a document conveyed by the automatic document feeder A.
An image control unit C for processing the read document image; a writing unit D including a writing unit 12 for writing on an image carrier 10 formed of a photosensitive drum in accordance with the data after the image processing; Around the charging electrode 14,
An image forming section E including image forming means such as a developing means 16 comprising a magnetic brush type developing device, a transfer electrode 18, a separation electrode 20, and a cleaning means 21, and a plurality of recording paper accommodation means such as a tray for accommodating recording paper P (Hereinafter referred to as a sheet feed tray or a tray) 22, 24, and the like.

The paper feed trays 22 and 24 of this embodiment are provided with a dial for setting the size of the recording paper P stored in the paper feed trays 22 and 24 by the user. The main components of the automatic document feeder A include a document table 26, a roller group including a roller R1, and a document feed processing unit 28 including a switching unit for appropriately switching a document moving path.

The original image reading section B is located below the original glass G and can move back and forth while maintaining the optical path length, and a fixed imaging lens (hereinafter, referred to as a lens).
33, a line-shaped image sensor (hereinafter referred to as CCD) 35, etc., and a writing unit D is a laser light source 40, a polygon mirror.
(Polarizer) 42 and the like.

The automatic document feeder A has a difference in configuration from a conventional automatic document feeder, but its principle is known per se, and the original image reading section B, writing section D, image processing means (image carrying means) An image forming apparatus and an image forming process including a unit that forms a toner image on the body 10 and transfers the toner image onto a sheet) are well known.
The description is briefly given.

R10 shown on the front side of the transfer electrode 18 is at a timing at which the leading end of the recording paper P conveyed from the paper feed trays 22 and 24 comes into contact with the recording paper P and coincides with the toner image on the image carrier 10. Is a registration roller for nipping and transporting to the image carrier 10. The driving of the registration roller R10 is performed by turning on and off a clutch (not shown).

In the vicinity of the upstream of the registration roller R10, there is provided a registration sensor 25 for detecting the recording paper P whose leading end is in contact with the registration roller R10. H shown on the downstream side of the separation electrode is a fixing device, which is provided with a heating roller 91 and a pressure roller 92 which is in pressure contact with the heating roller 91. A toner image is provided between the heating roller 91 and the pressure roller 92. The toner image is heat-fixed on the recording paper P by fixing the recording paper P on which is transferred.

In the above configuration, a process of forming a toner image on the image carrier 10, transferring the toner image on a sheet, and then discharging the toner image to a paper discharge tray is as follows. In this specification, a transfer area where a transfer electrode is located may be referred to as an image recording unit.

A document (not shown) placed on the document table 26 is transported in the document transport processor 28, and slit exposure is performed by the exposure means L while passing under the roller R1. It is.

The light reflected from the original passes through mirror units 30 and 31 and a lens 33 at fixed positions, is coupled onto a CCD, and is read. The image information read by the document image reading unit B is processed by the image processing means, encoded, and stored in a memory on the image control board C.

The image data is called in accordance with the image formation, the laser light source 40 in the writing section D is driven in accordance with the image data, and the image carrier 10 is exposed. Prior to this exposure, a predetermined surface potential is applied to the image carrier 10 rotating in the direction of the arrow (counterclockwise) by corona discharge of the charging electrode 14. As a result, an electrostatic latent image corresponding to the image data is formed on the image carrier 10.

The electrostatic latent image is reversely developed by the developing means 16 to be a visible image (toner image). On the other hand, the image carrier 10
Before the leading end of the upper toner image reaches the transfer area, for example, one sheet of recording paper P in the feed tray 22 is fed and conveyed, reaches the registration roller R10, and the leading end reaches the registration roller R10. Abutted and regulated.

The recording paper P is a toner image, that is, the image carrier 10
The sheet is conveyed toward the transfer area by a registration roller R10 that starts rotating in synchronization so as to overlap the upper image area.

In the transfer area, the toner image on the image carrier 10 is transferred onto the recording paper P by urging the transfer electrode, and the recording paper P is then separated from the image carrier 10 by urging the separation electrode 20. Separated.

After that, the toner powder forming the toner image is melted and fixed on the recording paper P by heating and pressing of the fixing device H, and the recording paper P is discharged through a paper discharge passage 78 and a paper discharge roller 79. The sheet is discharged onto the tray T.

Next, the electrical configuration of the invention portion of this embodiment will be described with reference to FIG. In the figure, 101 is a clutch of the registration roller R10, 111 is an image carrier motor for driving the image carrier 10 to rotate, and 121 is a display unit such as a liquid crystal for displaying a message to a user.

Reference numeral 200 denotes a recording paper P set by the user.
5 is a table in which a value obtained by converting the size (W) of the above into a timer measurement value described later is recorded. The control unit 500 has a timer 501 inside.

Next, the operation of the control unit 500 will be described with reference to FIGS.
This will be described with reference to FIG. Monitoring is performed until the leading edge of the recording paper P conveyed from the paper feed trays 22 and 24 comes into contact with the registration roller R10 and the registration sensor 25 is turned on (step
1).

When the registration sensor 25 is turned on, monitoring is performed until the registration roller clutch 101 is turned on (step 2). The registration roller clutch 101 is turned on, and the recording paper P is nipped and conveyed to the image carrier 10. If it is started, the timer 501 is started (step 3).

The measurement of the timer 501 is continued until the registration sensor 25 is turned off, that is, until the trailing edge of the recording paper P passes through the registration sensor 25 (step 4). The timer measurement value (A) is obtained (Step 5).

Next, referring to the table 200, the size information (W) of the recording paper P set by the user using the dials of the paper feed trays 22 and 24 is converted into a timer measurement value.
(B) is obtained (step 6).

If A = B (step 7), set copy number
Copy is performed for (I) (step 8). If A ≠ B
(Step 7), copying is performed up to n copies (n = 1, 2, 3,...), The apparatus is stopped (Step 9), and a message such as “Recording paper size setting check” is displayed on the display unit 121 (Step 7). Step 10).

According to the above configuration, the size of the supplied recording paper P is determined, and if the size of the recording paper P is different from the size set by the user, the apparatus is stopped to stop the recording paper P set by the user. When the size of the recording paper P actually supplied is different from the size of the recording paper (the entire toner image is not transferred to the recording paper. The jam detection device is activated, the device is stopped, and the thermostat is activated. (The operation of the above devices is prohibited, under-fixing etc.)
Can be prevented.

The present invention is not limited to the above embodiment. For example, if A <B in step 7 of FIG. 4, steps 9 and 10 are performed, and if A> B, the apparatus may be stopped by the jam detection unit.

[0038]

As described above, according to the present invention, the size of the supplied recording paper is determined, and if the size of the transfer paper is different from the size set by the user, the apparatus is stopped to allow the user to stop the operation. Trouble when the set recording paper size is different from the actual supplied recording paper size
(The entire toner image is not transferred to the recording paper. The jam detection device operates, the device stops, the thermostat operates, further operation of the device is prohibited, and under-fixing is prevented.) it can.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an electrical configuration of an embodiment.

FIG. 2 is a diagram illustrating an overall configuration of an image forming apparatus according to an embodiment.

FIG. 3 is a diagram illustrating an operation.

FIG. 4 is a diagram illustrating an operation.

[Explanation of symbols]

 Reference Signs List 10 image carrier 25 registration sensor 101 registration roller clutch 121 display unit 500 control unit R10 registration roller

Continued on the front page (72) Inventor Tomoya Motoyoshi 2970 Ishikawa-cho, Hachioji-shi, Tokyo F-term in Konica Corporation (reference) 2H027 DA38 DC04 DC10 EH10 EK03 FA05 GA30 3F048 AA01 AB01 BA07 BC03 CA03 EA01

Claims (2)

[Claims] 1. An image forming apparatus in which a user sets a size of a recording sheet, forms a toner image on an image carrier, and transfers the toner image onto the recording sheet, and determines a size of the supplied recording sheet. An image forming apparatus that stops the apparatus when the size of the transfer sheet is different from the size set by the user. 2. A registration roller that abuts a leading end of the supplied recording paper and nips and conveys the recording paper to the image carrier at a timing coincident with a toner image on the image carrier; and an upstream of the registration roller. A registration sensor that is provided in the vicinity and detects a trailing end of the recording paper conveyed to the image carrier by the registration roller; a display unit that displays a message to a user; The size of the supplied recording paper is determined from the time from when the registration roller is driven until the registration sensor detects the trailing end of the recording paper, and when the size of the supplied recording paper is different from the size set by the user. The image forming apparatus according to claim 1, further comprising: a control unit configured to stop driving of the apparatus and display a message on the display unit.