JP3212082B2 - Image recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus, and more particularly to an image recording apparatus in which cut sheets stored in a sheet cassette are fed one by one by a sheet feed roller. The present invention relates to a device capable of detecting not only a paper feed error after detection but also a paper feed delay.

[0002]

2. Description of the Related Art Conventionally, in an image recording apparatus such as a page printer, a facsimile machine, and a copying machine, a paper cassette containing a plurality of fixed cut papers, a paper feed mechanism having a paper feed roller and a registration roller, and an image on paper At the start of image recording, the paper feed roller is driven to rotate by a predetermined amount, and the paper in the paper cassette is fed one by one along the paper transport path. The registered paper is registered by a pair of registration rollers provided in the middle of the paper conveyance path (to align the front end of the fed paper), and the registered paper is recorded by the registration rollers and the conveyance rollers. The paper is sequentially conveyed to the mechanism, is subjected to recording processing by the recording mechanism, and is discharged to a paper discharge tray.

[0003] By the way, there is a possibility that the paper may not be normally fed due to the paper being caught in a part of the paper feed cassette even though the paper feed roller is driven to rotate during the paper feeding. Therefore, in general, a paper detection sensor for detecting the leading edge of the paper is provided at a predetermined position between the paper supply roller and the registration roller, and when the recording operation is started, the paper detection sensor is used. When a sheet is not detected, it is determined that normal sheet feeding is not being performed, that is, it is determined that a sheet feeding error has occurred, and the recording operation by the recording mechanism is stopped.

[0004]

As described above, in an image recording apparatus provided with a paper feeding mechanism, a recording mechanism, and the like,
When a recording operation is performed by the recording mechanism, a paper feed error is determined only when the paper is not detected by the paper detection sensor, and the recording operation is stopped. When the paper is fed from the paper cassette in, the paper feed roller slips or gets caught when the paper is art-coated or thick paper, and the paper feed roller has a predetermined amount. When the feed amount of the paper decreases due to the rotation of the paper, the paper feed operation by the paper feed roller is stopped immediately after the leading edge of the fed paper is detected by the paper detection sensor, and the leading edge of the paper reaches the registration roller. If the paper is not conveyed, there is no paper feed error, so the recording operation is performed with no paper, and when the recording mechanism is a laser printer in particular, toner adhering to the photosensitive drum Soiled device inside toner adheres like shooting roller, or the following problems such as toner soiling adhered to the back surface of the paper.

On the other hand, when the paper feed roller slips or the paper is caught, the paper is fed with a paper feed delay, the leading edge of the paper is detected by the paper detection sensor, and the paper is fed by the registration rollers. Means that the paper is behind the normal transport position with respect to the recording mechanism,
There is a problem that the recorded image is shifted with respect to the sheet, or the image is recorded so as to protrude from the sheet, thereby causing a defective portion in the image. SUMMARY OF THE INVENTION It is an object of the present invention to reliably detect not only a paper feed error in which paper is not fed but also a paper feed error fed in a state of paper feed delay when paper is fed by a paper feed roller. To provide a simple image recording apparatus.

[0006]

According to a first aspect of the present invention, there is provided an image recording apparatus comprising: a paper feed roller for feeding paper from a paper feed cassette; and a registration roller for registering the paper fed by the paper feed roller. In an image recording apparatus provided with paper means and recording means for recording an image on paper fed by the paper feeding means, a paper detecting means for detecting a leading edge of a paper between a paper feeding roller and a registration roller; Measure the time from the start of operation of the paper roller to the detection of the leading edge of the paper by the paper detection means,
A first misfeeds detecting means that measurement time is that there is a feeding mistake is longer than the first predetermined time, longer second predetermined than the paper feeding roller actuation start or al the first predetermined time And a second paper-feed error detecting means for determining that there is a paper-feed error when the paper detecting means does not detect the leading edge of the paper even after a lapse of time.

When the paper feed roller is driven by a predetermined rotation amount at the start of the recording operation, and the paper stored in the paper feed cassette is normally fed by the paper feed roller, the paper is fed toward the registration roller. Then, after the leading edge of the sheet is detected by the sheet detecting means, registration is performed by a registration roller, and thereafter, an image is recorded on the fed sheet by the recording means. By the way, when the paper is an art coat or a thick paper, the paper feed roller slips or the paper is caught, so that the paper feeding amount is reduced, and the leading edge of the fed paper is reduced. Immediately after the sheet is detected by the sheet detecting means, the sheet feeding operation by the sheet feeding roller is stopped, and when the sheet is not fed any more, or when the sheet is fed with the sheet feeding delayed, the (1) Since the paper feed error detecting means measures the time from the start of the operation of the paper feed roller to the detection of the leading edge of the paper by the paper detecting means, if the measured time is longer than the first predetermined time, the paper feed error is detected. Is detected.

That is, a slip occurs in a paper feed roller that is driven to rotate by a predetermined amount during paper feeding, or the paper is caught, so that the amount of paper fed by the paper feed roller is reduced, and the fed paper is When the paper feeding operation is stopped after the leading edge of the paper is detected by the paper detecting means, and the paper cannot be fed any more, a paper feeding error is reliably detected. The toner does not adhere to the transfer roller or the back surface of the paper and becomes dirty. In addition, if the paper feed roller slips or the paper gets caught, even if the paper is fed with a paper feed delay, a paper feed error will be reliably detected. Therefore, it is possible to reliably prevent image recording that is defective such that an image is shifted or chipped.

Furthermore, the to the paper feed roller sheet detecting means even after the lapse of a long second predetermined time than the working start or al the first predetermined time and there is a feeding mistake does not detect the leading end of the sheet since with 2 misfeeds detecting means, even after the lapse of a point or we second predetermined time when the operation of the paper feed roller is started,
If the paper detecting means does not detect the leading edge of the paper, the second paper feeding error detecting means can detect a paper feeding error.

According to a second aspect of the present invention, in the image recording apparatus according to the first aspect, when the first or second sheet-feed error detecting means detects a sheet-feed error, the sheet-feed error notification for notifying the sheet-feed error. Means are provided. In this case, when the first or second feeding error detecting unit detects the feeding error, the feeding error notifying unit notifies the feeding error. In addition, the same operation as the second aspect is achieved.

According to a third aspect of the present invention, in the image recording apparatus according to the second aspect, when the first or second paper misfeed detecting means detects a paper misfeed, it detects whether or not the recording means is in a recording operation, When a recording operation is being performed, a prohibition command unit for outputting a recording prohibition command to the recording unit at the end of recording on the recording sheet is provided. In this case, when the recording operation is being performed when the first or second paper supply error detecting means detects a paper supply error, the prohibition command means causes the recording means to be instructed at the end of recording on the paper being recorded. Since the recording prohibition command is output, the image recording during recording can be normally terminated. In addition, the same operation as the second aspect is achieved.

According to a fourth aspect of the present invention, in the image recording apparatus according to the first aspect of the present invention, when the first sheet mis-detection means or the second sheet mis-detection means detects a sheet mis-feed, the sheet mis-delay state is set. And a sheet feeding solenoid for feeding the sheet to the registration roller. When a paper feed error is detected by the first paper feed error detection means or the second paper feed error detection means, the paper feed delay state can be fed to the registration roller by driving the paper feed solenoid. , Can be fed normally.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. This embodiment includes a laser printer and an image scanner, and can realize normal facsimile functions such as recording received facsimile data and transmitting image information of a document, and has a telephone function, a sound function, etc. Multi-function device with a personal computer connected via a cable (hereinafter referred to as MFD (multi-function device)
1) (corresponding to an image recording apparatus) to which the present invention is applied.

First, the laser printer 3 will be described with reference to FIG. In the main body case 2, a feeder unit 10 for feeding fixed-size cut paper 4 to be used for image recording is provided.
(Corresponding to paper feeding means) and the laser scanner unit 2
0, a photosensitive drum 29, and the like.

First, the feeder unit 10 will be briefly described. A paper pressing plate 11 elastically urged upward by a compression spring 12 is disposed in a feeder section case 2a above a rear end of the main body case 2. A sheet cassette 13 containing a plurality of sheets 4 of fixed cut paper is removably mounted in an inclined manner so as to straddle the sheet pressing plate 11, and a sheet feeding roller 14 is driven by a drive (not shown). The mechanism is driven to rotate at a predetermined sheet feeding timing, and the sheets 4 stored in the sheet cassette 13 are fed one by one to the sheet feeding roller 1.
The paper is fed by feeding a predetermined amount by the enlarged radius portion 4.

By the way, as shown in FIGS. 1 and 2, the conveying direction (in FIG.
A pair of registration rollers 15 for aligning the leading end of the fed paper 4 are provided on the downstream paper guide wall 2b.
Are rotatably supported. In addition, a paper detection mechanism 17 that detects the leading end of the paper 4 is provided in proximity to the paper feed roller 14 side of the registration rollers 15. The sheet detecting mechanism 17 will be briefly described. A sheet having a projecting portion 18a projecting upward from the sheet guiding wall 2b and an operating portion 18b extending obliquely downward at the center in the left-right direction of the sheet guiding wall 2b. A detection lever 18 is rotatably supported by a pivot 19 extending in the left-right direction.

Further, the projecting portion 18 is
The sheet detection sensor 83 detects that the operating part 18b has rotated when the a has swung to the swing position indicated by the two-dot chain line.
Is provided. The paper detection sensor 83 includes a photo interrupter having a light emitting element and a light receiving element,
The projecting portion 18a swings to the swinging position at the leading end of the sheet 4 fed by the sheet feeding roller 14, and the operating portion 18b
When rotated to the operating position indicated by the dashed line, the emitted light emitted from the light emitting element toward the light receiving element is blocked, so that the leading end of the fed paper 4 is
3 can be detected. Here, a weight member 18c is provided integrally with the paper detection lever 18, and the paper detection lever 1 is so set that the protruding portion 18a is always in an upright state.
8 is urged to rotate.

The photosensitive drum 29 has a hollow shape in which a photoconductive layer of a predetermined thickness (for example, about 20 μm) in which a photoconductive resin is dispersed in polycarbonate is formed on the outer periphery of a cylindrical aluminum sleeve. And is rotatably supported by the main body case 2. That is, the toner 5 charged to the positive polarity is developed by the reversal development method with respect to the positive electrostatic latent image formed on the photosensitive drum 29.

The laser scanner unit 20 is disposed below the photosensitive drum 29, and is driven to rotate by a semiconductor laser emitter 21 for generating a laser beam LS for forming an electrostatic latent image on the photosensitive drum 29. A polygon mirror (pentahedral mirror) 22, a pair of lenses 23 and 24, a pair of reflection mirrors 25 and 26, and the like. The semiconductor laser emitter 21 is driven while rotating the photosensitive drum 29 in the illustrated rotation direction.
Main scanning of the laser light LS emitted from the polygon mirror 22 by rotating the polygon mirror 22 in a predetermined rotation direction, an electrostatic latent image can be formed on the photosensitive drum 29 by the lenses 23, 24 and the reflection mirrors 25, 26. it can.

On the other hand, at a position on the advance side in the rotation direction from a position on the photosensitive drum 29 where the laser beam LS is irradiated, a charge made of tungsten or the like is used to uniformly charge the surface of the photosensitive drum 29. A scorotron-type charger 27 for generating a corona discharge from the wire for use is provided, and a discharging lamp 28 for removing the charge on the surface of the photosensitive drum 29 is provided at a position further advanced in the rotation direction than the charger 27. Have been.

The developing unit case 2c is provided with an agitator 31 which is driven to rotate, and an insulating toner 5 having an electric insulating property.
Is mounted detachably, and a toner supplied by the rotation of an agitator 31 through a toner supply port formed in the toner box 30 is provided on the front side of the toner box 30. 5 is formed, and the toner storage chamber 32
The supply roller 33 is rotatably pivoted, and the developing roller 34 is rotatably pivoted so as to partition the front side of the toner storage chamber 32 and contact the supply roller 33 and the photosensitive drum 29, respectively. Have been.

Here, the toner 5 has a particle diameter of 7 to
It is made of synthetic resin having a thickness of 10 μm.
The developing roller 34 is made of conductive rubber.
On the other hand, a thin plate-like elastic layer-thickness regulating blade 35 made of stainless steel or phosphor bronze is provided on the developing unit case 2c.
Is attached downward, and a bent portion formed at the lower end thereof is in contact with the developing roller 34 in a pressing manner, and the layer thickness of the toner 5 supplied from the supply roller 33 and adhered to the surface of the developing roller 34 in a layered manner. Is regulated by the layer thickness regulating blade 35.

Then, the photosensitive drum 29, the supply roller 3
3. Since the developing roller 34 and the like are each driven in a predetermined rotation direction by the driving mechanism, each toner particle of the toner 5 is rubbed between the supply roller 33 and the developing roller 34 and the developing roller 34 of the layer thickness regulating blade 35. The toner 5 charged to a positive polarity due to the pressing friction against the toner is adhered to the electrostatic latent image formed on the photosensitive drum 29 by the laser beam LS, and is developed by a reversal developing method.

Next, a transfer roller 36 made of conductive rubber is provided so as to be in contact with the upper side of the photosensitive drum 29 and is rotatably supported by a pivot. The toner image on the photosensitive drum 29 is transferred by the transfer roller 36. , Is surely transferred to the sheet 4. The fixing unit 40 is provided downstream of the photosensitive drum 29 in the transport direction and includes a heating roller 42 having a fixing heater 41 such as a halogen lamp and a pressing roller 43, and the toner image transferred to the lower surface of the sheet 4. Is heated at the same time as the pressing, and is fixed to the sheet 4.

Next, the image scanner 45 for reading the image of the document 7 will be briefly described. An operation panel 6 having a liquid crystal display 6a and a keyboard 6b provided with keys such as a numeric keypad and various function keys is provided at an upper portion on the front side of the main body case 2. An image scanner 45 for reading an image recorded in the image 7 is provided. In the image scanner 45, when the original 7 is transported to a predetermined reading position along the original receiver 46 by an original transport mechanism (not shown), the original 7 is irradiated with light by a light source (not shown) and reflected from the original 7. The light is reflected by mirrors 47 and 48,
An image on the original 7 is read line by line by receiving light from a reading head 49 including a light receiving element in which a plurality of CCDs (charge coupled elements) are arranged.

Next, the control system of the MFD 1 will be described with reference to FIG. Basically, a control unit 60 having a control unit 50, an operation panel 6 connected to the control unit 60, a laser printer 3
, An image scanner 45, and a speaker 70 for outputting sound such as voice.

The control unit 50 basically includes a CPU 51
A ROM 52 connected to the CPU 51 via a common bus 56 including a data bus, an EEPROM (an electrically erasable and rewritable ROM) 53, and a RAM 54.
And a DMA controller 55 and the like. Also, the common bus 56 has a shortened (compressed) image information.
COD having a coding unit for coding for decoding and a decoding unit for decoding communication data shortened by coding
EC61 and I / O AS consisting of a hard logic circuit
An IC (application-specific integrated circuit) 62 is connected.

Further, a speaker 70 is connected to the common bus 56.
Amplifier (AMP) 63 for driving a telephone, a modem 64 for facsimile communication capable of handling sound data such as voice, a buffer 66, and a personal computer 9
And a Centronics-compatible communication interface (communication I / F) 67 connected via a connection cable L to each of them.

An NCU (Network Control Unit) 65 connected to the telephone line 8 and the handset 71 is connected to the modem 64. Furthermore,
The input / output ASIC 62 is connected to an operation panel 6 having a display 6a capable of displaying a plurality of characters and symbols and a keyboard 6b, and the laser printer 3, and an image scanner via a DRAM (dynamic RAM) 68. 45 are connected. That is, the DRAM 6
In 8, dot data for two or three dot lines read by the image scanner 45 is temporarily stored as image information, and the image information is read by the input / output ASIC 62.

In the laser printer 3, as shown in FIG. 4, a polygon mirror motor 80 for rotating and driving the polygon mirror 22, the paper feed roller 14 and the registration roller 1 are provided.
5 and an LF motor 8 for driving a conveying roller (not shown)
1. Feeding solenoid 8 for starting rotation of semiconductor laser light emitting device 21, fixing heater 41, and feed roller 14
2. ASI for input / output, charger 27, static elimination lamp 28, etc.
The sheet signal PS from the sheet detection sensor 83 is driven by a drive signal from the C62, and the input / output ASIC
The signal is output to the common bus 62 by 62.

The ROM 52 controls the transmission and reception of image information to and from an external facsimile machine (not shown) via the telephone line 8 by operating the laser printer 3 or the image scanner 45, and also controls recording and image reading. A control program for realizing a facsimile function, a control program for realizing a copy function for recording image information of the document 7 read by the image scanner 45, a control program for realizing a printer function for recording print data received from the personal computer 9, A control program for realizing an image reader function of transmitting image information of the document 7 read by the image scanner 45 to the personal computer 9 is stored.

Further, the ROM 52 realizes a reception control program for temporarily storing the received facsimile data in the reception data memory 54a of the RAM 54, and a telephone function for transmitting and receiving a voice signal to / from the other party via the telephone line 8. A control program for realizing a sound function of outputting sound information received via the telephone line 8 to the speaker 70, a control program for paper feed error detection control described later, and the like are stored. Here, the photosensitive drum 2
9, the laser scanner unit 20, the recording control program, the control unit 50, etc., constitute recording means.

Here, in the MFD 1, the C
The PU 51 can receive a time-division interrupt by a time-division interrupt timer (built-in timer) that counts a clock signal from a clock connected thereto in a hardware manner. When a plurality of sets of control programs are to be processed in parallel, for example, when the facsimile data transmission control program of the facsimile function and the control program of the printer function are processed in parallel, the CPU 51 sets the CPU 51 to, for example, about 1/60 second ( Each time a time-sharing interrupt of about 16 msec is received, a plurality of functions can be realized at the same time by sequentially switching these plural sets of control programs in a time-sharing manner about every 1/60 seconds assigned to them. It has become.

In the EEPROM 53, various setting modes for realizing the facsimile function, various setting data relating to the printing position and the printing density for realizing the printer function are changeably stored, and a plurality of destinations are stored. Is stored. The RAM 54 includes a reception data memory 54a for storing received facsimile data, a memory for temporarily storing print data, sound information, and the like, and a control program for implementing a plurality of functions such as a facsimile function and a copy function. Various necessary memories and buffers are provided.

Next, a description will be given, with reference to the flow chart of FIG. 5, of a routine of the paper feed error detection control performed by the control unit 50 of the MFD 1. The symbols Si (i = 10, 11, 12,...) In the flowcharts described below are each step. By the way, a first predetermined time T described later
1 (for example, about 2 seconds) and a second predetermined time T2 (for example,
"About 5 seconds" means that the data is stored in the EEPROM 53 in advance. Prior to the start of the recording operation for recording the facsimile data for a plurality of pages received via the telephone line 8, the paper feeding solenoid 82 is driven and the paper feeding roller 1 is driven.
When the paper feed operation by the rotation of 4 is started, this control is started. First, a timer t built in the CPU 51 is reset and a count operation is started (S10).

Next, the paper signal PS from the paper detection sensor 83 is read, and if the paper signal PS is at the "L" level and the leading edge of the paper is not detected (S11: No), the timer value t
Is read, and when the timer value t is shorter than the second predetermined time T2 (S12: No), S11 to S12 are repeatedly executed. Here, the second predetermined time T2 is a state in which the leading edge of the sheet 4 is not detected by the sheet detection sensor 83 despite the start of sheet feeding, that is, a set time for determining that there is a sheet feeding error. , S12, the timer t, the second predetermined time T2, the sheet detection sensor 83, etc., constitute a second sheet supply error detecting means.

When the sheet signal PS becomes "H" level and the leading edge of the sheet is detected by the sheet detection sensor 83 (S11: Yes), when the timer value t is shorter than the first predetermined time T1, That is, when paper is fed by the paper feed roller 14, no slip occurs or the paper 4 is caught on the paper feed cassette 13, and the paper 4 in the paper feed cassette 13 is synchronized with the rotation of the paper feed roller 14. When the paper is fed and transported smoothly at the normal paper feed timing (S1
3: No), a recording start command is output to the recording control program (S14), this control is terminated, and the process returns to the main routine.

By the way, when the leading edge of the sheet is
When the timer value t is detected by the second predetermined time T2
Has not elapsed, but when the first predetermined time T1 or more has elapsed (S11 / S12: Yes), the paper feed roller 14
When the paper is fed, the paper may be slippery due to the art coat or thick paper,
Is caught in the paper feed cassette 13 and the arrival of the leading edge of the paper at the position of the paper detection sensor 83 is delayed.
Is stopped at the position immediately before the above, a message of a paper feed error is displayed on the display 6a (S15). Here, S13, timer t, first predetermined time T1
The first sheet feeding error detecting means is constituted by the paper feed sensor 83 and the sheet detecting sensor 83, and the sheet feeding error notifying means is constituted by S15 and the display 6a.

Next, the current recording operation is the first page,
When the recording operation is not performed (S16: No), a recording prohibition command is output to the recording control program (S16).
18) Then, a message to the effect that recording is stopped is additionally displayed on the display 6a (S19), and the process returns to the main routine in the same manner. On the other hand, when a paper feed error is detected, if the current printing operation is the second and subsequent pages and the printing operation is being performed (S16: Yes), the printing operation of the page being printed is ended. Until the recording operation during recording is completed (S17: Yes)
), S18 to S19 are executed, and similarly, the process returns to the main routine. Here, S16-S18 and display 6
"a" and the like constitute prohibition command means.

By the way, when the leading edge of the sheet is not detected by the sheet detecting sensor 83 and the timer value t has passed the second predetermined time T2 or more (S1).
2: Yes), when paper is fed by the paper feed roller 14, slippage occurs, or the paper 4 is caught in the paper feed cassette 13, and the paper 4 is not fed at all. Therefore, the process returns through S15 to S19. Here, as shown in FIG. 6, a paper feed solenoid 85 is provided on the paper guide wall 2b immediately downstream of the paper feed roller 14A in the transport direction, and a paper feed solenoid 85 is provided toward the downstream in the diagonal transport direction. Attaches a needle-shaped needle member 86, and when a paper feeding error is detected in S12 or S13, the paper feeding solenoid 85 is set to, for example, 1
By driving 0 to 15 times, the paper 4 in the paper feed delay state can be fed to the pair of registration rollers 15A by the needle member 86, and the paper can be normally fed.

As described above, when the paper feed roller 14 is rotated by a predetermined amount at the time of paper feed, a slip occurs, or when the paper 4 is caught on the paper feed cassette 13, the paper When the feeding amount of the paper 4 becomes small and the leading edge of the fed paper 4 is detected by the paper detection sensor 83, the paper feeding operation is stopped, and when paper feeding cannot be performed any more, a paper feeding error is reliably detected. Therefore, the recording operation can be prohibited, and the toner 5 on the photosensitive drum 29 does not adhere to the transfer roller 36 or the back surface of the paper 4 to be stained. In addition, even if paper is fed with a delay in paper feeding due to slippage of the paper feeding roller 14 or paper being caught, a paper feeding error is reliably detected, and the recording operation is prohibited. Therefore, it is possible to reliably prevent the image recording that is a defect in which the image is shifted or missing.

Further, even if the second predetermined time T2 or more has elapsed since the start of the operation of the paper feed roller 14, even if the paper detection sensor 83 does not detect the leading edge of the paper, it is possible to detect a paper feed error. it can. When a paper feed error is detected, the error of the paper feed error can be displayed on the display 6a to notify the paper feed error. Further, if a recording error is detected and a recording operation is being performed, the recording operation is prohibited at the end of recording on the sheet 4 being recorded. Therefore, it is necessary to normally terminate image recording during recording. Can be.

Here, as a modification of the above embodiment,
The sheet detection sensor 83 for detecting the leading edge of the sheet may be constituted by a light reflection type optical sensor. Also, the timer t
In place of the above, a configuration may be adopted in which the clock is measured with a count value for counting a predetermined clock signal. Further, the personal computer 9 may be a notebook or laptop portable device equipped with a communication function, or a plurality of personal computers 9 may be connected. Furthermore, it is possible to realize multiple functions such as telephone function, facsimile function, answering machine function, etc., and a photosensitive drum or photosensitive belt with an LED array in which a large number of light emitting diode elements that emit infrared light or red visible light are linearly arranged. A recording mechanism for forming an electrostatic latent image thereon is provided, and the present invention is applied to various image recording apparatuses such as a multifunction apparatus connected to various networks, and further a copying machine and a facsimile apparatus. You may.

[0044]

According to the first aspect of the present invention, there is provided an image recording apparatus including a paper feed roller for feeding paper from a paper feed cassette and a registration roller for registering the paper fed by the paper feed roller. And a recording unit for recording an image on a sheet fed by the sheet feeding unit,
A paper detection unit and a first paper supply error detection unit are provided, and the paper supply roller, which is driven to rotate by a predetermined amount during paper supply, generates a slip or catches the paper. The paper feed operation is stopped after the feeding amount is reduced and the leading edge of the fed paper is detected by the paper detecting means. Can be prohibited, and the toner on the photosensitive drum does not adhere to the transfer roller or the back surface of the sheet to be stained. In addition, if the paper feed roller slips or the paper gets caught, even if the paper is fed with a paper feed delay, a paper feed error will be reliably detected. Therefore, it is possible to reliably prevent image recording that is a defect in which the image is shifted or missing.

[0045] Since further comprising a second misfeeds detecting means, even after the lapse of a long second predetermined time than a point or we first predetermined time when the operation of the paper feed roller is started, the sheet detecting means Paper If the leading end is not detected, a paper feed error can be detected. According to the image recording apparatus of the second aspect, the same effect as that of the first aspect is obtained, but since the feeding error notification unit is provided, the feeding error is detected by the first or second feeding error detecting unit. At times, the paper feed error can be notified.

According to the image recording apparatus of the third aspect, the same effect as that of the second aspect is obtained, but since the prohibition command means is provided, the first or second paper misfeed detecting means detects a paper misfeed. When a recording operation is being performed, a recording prohibition command is output to the recording unit when the recording on the recording sheet is completed, so that the recording of the image being recorded can be normally terminated.

According to the image recording apparatus of the present invention, when the first paper feeding error detecting means or the second paper feeding error detecting means detects a paper feeding error, the paper feeding solenoid is driven to supply the paper. The paper in the paper delay state can be fed to the registration roller, and can be normally fed. The other effects are the same as those of the first aspect.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view of a multifunction device according to an embodiment of the present invention.

FIG. 2 is a partially enlarged side view of a feeder unit.

FIG. 3 is a block diagram of a control system of the multifunction device.

FIG. 4 is a block diagram of a control system of the laser printer.

FIG. 5 is a schematic flowchart of a paper feed error detection control routine.

FIG. 6 is a diagram corresponding to FIG. 2 according to a modified embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Multifunction device 3 Laser printer 4 Paper 6a Display 10 Feeder unit 13 Paper feed cassette 14 Paper feed roller 15 Registration roller 17 Paper detection mechanism 18 Paper detection lever 20 Laser scanner unit 29 Photosensitive drum 50 Control unit 51 CPU 52 ROM 54 RAM 83 Paper detection sensor 85 Paper feeding solenoid

Claims (4)

(57) [Claims] 1. A paper feeding device including a paper feeding roller for feeding paper from a paper feeding cassette, a registration roller for registering the paper fed by the paper feeding roller, and a paper fed by the paper feeding device. An image recording apparatus comprising: a recording unit that records an image on a sheet; a sheet detection unit that detects a leading edge of the sheet between the sheet feeding roller and the registration roller; measures the time until the detection of the tip, the measurement time and the first misfeeds detecting means that there is a feeding mistake is longer than the first predetermined time, actuating start or al the said feed roller And a second paper-feed error detecting means for determining that there is a paper-feed error when the paper detecting means does not detect the leading edge of the paper even after a second predetermined time longer than the first predetermined time has elapsed. Image recording device. 2. A paper feeding error notifying means for notifying a paper feeding error when the first or second paper feeding error detecting means detects a paper feeding error. Image recording device. 3. When the first or second paper-feed error detecting means detects a paper-feed error, the recording means detects whether or not a recording operation is being performed. 3. The image recording apparatus according to claim 2, further comprising a prohibition command unit that outputs a recording prohibition command to the recording unit at the time of termination. 4. A paper feeding solenoid for feeding paper in a paper feeding delay state to the registration roller when a paper feeding error is detected by the first paper feeding error detecting means or the second paper feeding error detecting means. The image recording apparatus according to claim 1, wherein: