JPH1124506A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent recording materials fed in an overlapped state from being wasted, also, to maintain good printing quality and to improve usability and reliability at forming an image. SOLUTION: An overlapped-feeding detecting part 24c for outputting a detection signal showing the thickness of an envelop is installed in a feeding unit 24, then, the envelop is fed from the feeding unit 24 to a printer main body. In this case, it is judged by an envelop feeder control part 24a that envelops are fed in an overlapped state based on the detection signal outputted from the part 4c and which shows that the envelop is thicker than the previously set thickness of an envelop, then, an envelop feeding operation is stopped by the control part 24a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus having a detecting unit for detecting a double feeding of a recording material in a feeding unit detachable from a print main body.

[0002]

2. Description of the Related Art A conventional electrophotographic printer system as an image forming apparatus is configured as shown in FIG. That is, in FIG. 1, reference numeral 201 denotes a drum-type electrophotographic photosensitive drum (hereinafter, simply referred to as a “photosensitive drum”) as an image carrier for forming an electrostatic latent image;
, A charging roller for uniformly charging the photosensitive drum 201; 203, a developing device for visualizing an electrostatic latent image on the photosensitive drum 201; 204, a toner container of toner serving as a developer; 205, A cleaner for cleaning the transfer residual toner on the photosensitive drum 201,
1, charging roller 202, developing machine 203, toner container 20
4 and a cleaner 205 constitute a process cartridge 206. The process cartridge 206 is detachable from the printer main body 200.

Reference numeral 207 denotes a laser transmitter serving as a light source for forming an electrostatic latent image on the photosensitive drum 201; 208, a polygon mirror for scanning a laser beam on the photosensitive drum 201; An optical unit 210 includes a laser transmitter 207, a polygon mirror 208, and a return mirror 209.
Is a paper cassette for stacking paper, which is a recording material provided as standard equipment in the printer main body 200, 212 is a paper presence / absence sensor that detects presence / absence of paper in the paper cassette 211,
Reference numeral 213 denotes a paper feed roller for feeding the paper on the paper cassette 211 to the conveyance path, 214 denotes a separation claw for separating the paper at the time of paper feeding, 215 and 216 denote conveyance rollers, and 217
Are registration rollers 218 for correcting skew of the paper.
Is a TOP sensor for detecting the leading edge of the sheet and determining the timing of image writing and transfer to the sheet, 219 is a transfer roller for transferring the toner on the photosensitive drum 201 to the sheet, and 220 is a transfer roller for transferring the toner on the sheet. 221 is a fixing unit having a fixing roller and a pressure roller for fixing the toner, and a sheet discharge sensor 221 detects whether or not the sheet is normally output from the fixing unit 220. This is a discharge roller that conveys the sheet until it is discharged outside. These constitute the printer body 200.

Next, the configuration of a feeding unit that can be attached to and detached from the printer main body 200 will be described.

Reference numeral 224 denotes an optional envelope feeder as a feeding unit for specially feeding an envelope serving as a recording material. Reference numeral 225 denotes an envelope feed roller for feeding the envelope in the optional envelope feeder 224; An envelope transport roller that feeds the paper envelope into the printer main body 200.

Reference numeral 227 denotes an optional cassette feeder attached to a lower portion of the printer main body 200.
Is an optional feeder cassette, 229 is an optional cassette paper presence / absence sensor for detecting the presence / absence of paper in the optional cassette 228, 230 is an optional cassette feed roller, 231 is a separation claw of the optional cassette 228, and 232 is an optional cassette transport roller It is.

Reference numeral 233 denotes an optional double-sided conveyance unit for conveying the recording material on both sides. Reference numeral 234 denotes a discharge flapper for switching a conveyance path depending on whether the paper is conveyed on both sides or discharge. Reference numeral 235 denotes a single-sided printed paper. An inversion flapper that switches the inversion path for inversion, 2
36 is a reversing roller for reversing the sheet by performing normal rotation and reverse rotation, 237 and 238 are two-sided conveying rollers for conveying the sheet on both sides, and 239 are two-sided conveying rollers 237 and 23 once.
A double-sided paper re-feeding roller 240 for feeding the paper conveyed by 8 into the image forming section, and 240 is a paper re-feeding sensor for detecting a paper re-feeding position.

FIG. 12 is a functional block diagram for controlling the electrophotographic printer system having the above configuration.

In FIG. 1, reference numeral 301 denotes image data from a host computer which is developed into dot information for turning on a laser transmitter 207, and which requests a printer engine to print or instructs the state of the engine when printing. The printer controller 302 controls the printer engine, which will be described later, in accordance with instructions from the printer controller 301. The engine controller 302 controls a driving system for transporting sheets. , An optical system control unit that executes control of a scanner motor and a laser based on an instruction from the engine control unit 302; 305, a charging roller 202;
A high-voltage control unit that executes various high-voltage outputs of the developing device 203 and the transfer roller 219 based on an instruction from the engine control unit 302;
A fixing unit temperature control unit 306 that controls the temperature of the fixing unit 220 to a predetermined temperature based on an instruction from the engine control unit 302;
Reference numeral 307 denotes an optional communication control unit as notification means for communicating with each of the optional double-sided conveyance unit 233, optional envelope feeder 224, and optional cassette feeder 227, and reference numeral 308 denotes a paper presence / absence sensor 21.
Reference numeral 309 denotes an external jig control unit for detecting the state of a sensor such as 2,229 or the TOP sensor 218.

FIG. 13 is a block diagram showing a configuration of a communication portion between the option communication control section 307 and each option feeding unit.

An optional envelope feeder 224, an optional cassette feeder 2
Signals of / SEL1, / SEL2, and / SEL3 are connected to 27 and optional double-sided conveyance unit 233, respectively. The / SEL1 signal or / SEL3 signal is a signal for specifying an option to be communicated by the option communication control unit 307, and the option feeding units 224, 227, and 233 determine that this signal is "true", and It can recognize that it is a communication target.

The same / SCLK signal is sent from the option communication control unit 307 to each option feed unit 22.
4,227,233. Similarly, / SIN, /
The optional communication control unit 307 also controls the SOUT signal.
From each optional feeding unit 224, 227, 233
Is communicated as a common signal.

In such a configuration, the option communication control unit 307 includes the option feed units 224 and 22
7 and 233 are subjected to communication processing as shown in FIG. That is, each optional feeding unit 224, 2
Commands and status are sequentially exchanged in a time series for each of 27 and 233.

The commands and statuses shown here are, for example, a command for instructing a paper feed start for an option or an option status.

In such an electrophotographic printer system, conventionally, in a case where the flap portion of the envelope is set to be overlapped with a feed unit dedicated to the envelope, etc.
The envelope is conveyed while being double fed, and as a result, the fixing device 220
Had jammed the envelope.

[0016]

However, in the above-described conventional electrophotographic printer system, an image is formed on a recording material by executing a normal electrophotographic process. Occurs, for example,
If a jam occurs in a place where the multi-fed paper is difficult for the user to process, and as a result the multi-fed recording material is wasted, the usability and reliability of the electrophotographic printer are impaired. there were.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and it is possible to eliminate waste of a multi-fed recording material and to maintain print quality to improve usability and reliability accompanying image formation. It is an object of the present invention to provide a recording material feeding device and an image forming apparatus having the same.

[0018]

In order to achieve the above object, an image forming apparatus according to the first aspect of the present invention is configured such that a thick recording material on which a toner image is formed is attached and detached so as to be supplied to a printer body. A feeding unit that is mounted so as to be capable of feeding the recording material from the feeding unit to an image forming unit, forming a toner image on the image forming unit, and from the image forming unit to the recording material. A control unit for controlling each unit of the printer engine for fixing the transferred toner image by a fixing unit.

A thickness detecting means provided in the feeding unit for detecting the thickness of the recording material fed to the printer body; and a fixing temperature of the fixing means or a fixing temperature based on a detection signal from the thickness detecting means. Control means for controlling a driving unit of the feeding unit.

According to the second aspect of the present invention, when the detection signal from the thickness detecting means is information indicating that the thickness is larger than a predetermined thickness of the recording material, the control means controls the thick recording. The feeding of the recording material is stopped when it is determined that the materials have been multi-fed.

According to the third aspect of the present invention, the control means stops feeding before the recording material reaches the image forming section of the printer main body.

According to the fourth aspect of the present invention, the control means includes a recording material for transmitting the thickness information communicated to the printer main body based on a detection signal from the thickness detecting means to the printer main body. If the thickness of the recording material is less than two and the recording material is thicker than one of the recording materials, it is determined that a recording material thicker than the thick recording material has been fed, and the fixing temperature is increased. On the other hand, when the thickness of the recording material is two or more, it is determined that the thick recording material has been multi-fed and switching control is performed so as to lower the fixing temperature.

According to the fifth aspect of the present invention, the thickness detecting means detects the deviation of the conveying member provided in the feeding unit as the recording material passes, and the optical detecting means And a notifying means for notifying as thickness information when the deviation of the conveying member detected by the above is larger than a predetermined value.

According to the sixth aspect of the present invention, the thickness detecting means includes a distance measuring means for measuring that the position of the conveying member provided in the feeding unit is deviated as the recording material passes. An informing means for comparing the distance information measured by the distance measuring means with the threshold information and informing the thickness information.

[Operation] Based on the above configuration, the feeding unit is provided with a thickness detecting means for detecting the thickness of the recording material.
The recording material is fed from the feeding unit to the printer body. At this time, based on a detection signal from the thickness detecting means, the driving unit of the feeding unit is stopped via the control means, and the fixing temperature of the fixing means is switched and controlled.

[0026]

Embodiments of the present invention will be described below in detail with reference to the drawings. <First Embodiment> FIG. 1 is a schematic configuration diagram showing an image forming apparatus according to an embodiment of the present invention, FIG. 2 is a functional block diagram for controlling a print engine of the image forming apparatus, and FIG. FIG. 3 is a block diagram showing a configuration of a communication portion between an option communication control unit and each option feeding unit.

In FIG. 1, 1 is a photosensitive drum for forming an electrostatic latent image, 2 is a charging roller for uniformly charging the photosensitive drum 1, and 3 is an electrostatic roller on the photosensitive drum 1. A developing device for visualizing the latent image; 4, a toner container for toner serving as a developer; and 5, a cleaner for cleaning untransferred toner remaining on the photosensitive drum 1, and a photosensitive drum 1, The process cartridge 6 is constituted by the roller 2, the developing device 3, the toner container 4 and the cleaner 5. The process cartridge 6 is detachable from the printer main body.

Reference numeral 7 denotes a laser transmitter serving as a light source for forming an electrostatic latent image on the photosensitive drum 1; 8, a polygon mirror for scanning a laser beam on the photosensitive drum 1;
Is a turning mirror, and the laser unit 7, polygon mirror 8 and turning mirror 9 constitute an optical unit 10. 11 is a paper cassette for loading paper, which is a recording material provided as standard equipment in the print body,
Reference numeral 12 denotes a paper presence / absence sensor for detecting the presence / absence of paper in the paper cassette 11, reference numeral 13 denotes a paper feed roller for feeding the paper stacked in the paper cassette 11 to a transport path, and reference numeral 14 denotes a paper when feeding paper. Separation pawls for separation, 15 and 16 are transport rollers, 17 is a registration roller for correcting skew of the paper, 18 detects the leading edge of the paper, and determines the writing position of the image and the timing of transfer to the paper. Sensor 19, a transfer roller for transferring the toner on the photosensitive drum 1 to the paper, and a fixing roller 20 having a fixing roller and a pressure roller for fixing the transferred toner to the paper. A paper discharge sensor 21 for detecting whether or not the paper is normally output from the fixing device 20;
Reference numerals 22 and 23 denote discharge rollers for transporting the paper until the paper is discharged out of the printer main body. The printer main body is constituted by the above-described members.

Next, the configuration of a feeding unit that can be attached to and detached from the printer body will be described.

As shown in FIG. 1, reference numeral 24 denotes an optional envelope feeder as a feeding unit for specially feeding the envelope. Reference numeral 25 denotes an envelope feed roller for feeding the envelope in the optional envelope feeder 24; Reference numeral denotes an envelope transport roller as a transport member for feeding the fed envelope into the printer body. Reference numeral 27 denotes an optional cassette feeder attached to a lower portion of the printer body; 28, a cassette for the optional feeder; 29, an optional cassette paper presence / absence sensor for detecting the presence / absence of paper in the optional cassette 28; , 31
Denotes a separation claw of the optional cassette 28, and 32 denotes an optional cassette transport roller.

Reference numeral 33 denotes an optional double-sided conveyance unit for performing double-sided conveyance, reference numeral 34 denotes a discharge flapper for switching the conveyance path depending on whether the paper is conveyed on both sides or discharge, and reference numeral 35 denotes a single-sided printed paper. A reversing flapper for switching a reversing path for reversing, 36 is a reversing roller for reversing the sheet by performing normal rotation and reverse rotation, and 37 and 38 perform printing on the other side of the sheet printed on one side. Double-sided transport roller that transports the paper in order to
Reference numeral 9 denotes a double-sided paper re-feeding roller for feeding the paper once conveyed by the double-sided conveying rollers 37 and 38 to the image forming section, and reference numeral 40 denotes a paper re-feeding sensor for detecting a re-feeding position.

Next, functional blocks for controlling the configuration of the electrophotographic printer system configured as described above will be described with reference to FIG. In the figure, reference numeral 101 denotes image data from a host computer which is developed into dot information for turning on the laser transmitter 7, a print request to a printer engine or an instruction of the state of the engine at the time of printing. A printer controller for checking the internal state of the engine; 102, an engine control unit for controlling each part of a printer engine, which will be described later, in accordance with instructions from the printer controller 101; An optical system control unit 104 executes control of a scanner motor and a laser based on an instruction from the engine control unit 102, and 105 controls various high-voltage outputs of charging, development and transfer to the engine control unit 102. The high-voltage control unit executed based on the instruction of A fixing unit temperature control unit that controls the temperature of the fixing unit 20 to a predetermined temperature based on an instruction from the engine control unit 102. Communication unit 107 communicates with each of the optional double-sided conveyance unit 33, the optional envelope feeder 24, and the optional cassette feeder 27. Optional communication control unit as a notification means for exchanging
Reference numeral 108 denotes a sensor input unit that detects sensor states of the paper presence / absence sensors 12, 29 and the TOP sensor 18.

The configuration of the communication section between the option communication control section and each of the option feeding units will be described with reference to FIG. 3. In FIG. 3, the option communication control section 107 as a communication means is provided for each of the option feeding units. On the other hand, signals of / SEL1, / SEL2 or / SEL3 are connected correspondingly. This / SEL1 to SEL3
The signal is a signal for specifying an option to be communicated by the option communication control unit 107. When this signal becomes “true”, the option side can recognize that it is a communication target.

As for the / SCLK signal, the same signal from the option communication control unit 107 is connected to each option. The / SIN signal and / SOUT signal are also connected as signals common to each option.

In such a physical configuration, each feed option returns status information indicating the internal state of the option to the printer main body via the / SIN signal based on the command information from the / SOUT signal of the printer main body. As shown in FIG. 4, internal information on STATUS0 is shown as an example of the status from the optional envelope feeder 24 to the printer main body. The serial communication performed here is an 8-bit serial communication, and the first bit is a bit for an error status.
The th bit has odd parity. The other 6 bits are used to broadcast information on various options. Here, the 7th bit is a bit indicating that multi-feeding is being performed, and the printer main body can determine whether or not the optional envelope feeder 24 has detected multi-feeding by reading at least STATUS0. .

Here, the function of detecting the double feed of envelopes in the optional envelope feeder 24 will be described with reference to FIG.

FIG. 5 is a schematic configuration diagram showing the inside of the optional envelope feeder 24.

In FIG. 5, reference numeral 24a designates an envelope feeder control unit as a control means for controlling each mechanism in the optional envelope feeder 24, and 24b designates an envelope feeder control. The drive unit drives the rollers of each transport unit based on the information from the unit 24a. The drive unit 24b also drives a paper feed roller 25 having an envelope pickup function. 24c is a double feed detecting unit as a thickness detecting unit for detecting the thickness of the envelope being fed, and notifying the information to the envelope feeder control unit 24a;
26a is a retard roller for separating the fed envelope, and the retard roller 26a is an envelope transport roller 26a.
The envelope is conveyed to the printer body via the printer.

Next, the actual functional configuration of the double feed detecting section 24c in the present embodiment will be described with reference to FIG.

In FIG. 6, the envelope transport roller 26 includes:
The transport rollers 26b are disposed to face each other. The transport roller 26b is held by the transport roller holder 26c. One end of a rotatable lever 41 is in contact with the transport roller holder 26c. This lever 41
The shaft 41a is rotatably supported about a shaft 41a, and the length of the other end is longer than the one end of the shaft 41a to amplify a slight movement of one end of the lever 41. Reference numeral 42 denotes a photo sensor disposed on the other end side of the lever 41. The photo sensor 42 as the optical detecting means is shielded or transmitted by the rotation of the lever 41. The photo sensor 42 is attached to a sensor holder 43.

The detection of the thickness of the envelope is performed by the envelope transport roller 26.
While the envelope is passing through, the transport roller 26b moves in the illustrated arrow X1 direction due to the thickness of the envelope, and the transport roller holder 26c moves up and down in conjunction with this, whereby the vertical movement of the transport roller holder 26c is controlled by the lever 41. Senses. As a result, the movement of one end of the lever 41 is amplified at the other end with respect to the shaft 41a, and the movement of the other end of the lever 41 is indicated by an arrow X2 in the figure.
Large conversion in the direction. Thereby, the photo sensor 42
As a result, when the lever 41 is displaced by a predetermined amount or more, the light-shielding / light-transmitting condition of the photo sensor 42 is changed, and is transmitted to the envelope feeder controller as 1/0 information.

FIG. 7 is a flowchart showing a method for detecting a double feed in the envelope feeder control section 24a. The envelope feeder control unit 24a is in a wait state until a paper feed start request is received from the printer body (ST1). Then, upon receiving a paper feed start request, driving of each roller is started (S
T2). Next, a predetermined time T1 from the start of driving of each roller
The time T1 is set so as to perform the double feed detection for the period (ST3), and when the photo sensor 42 enters the double feed state during the double feed detection period (ST4) (ST6), the double feed state is continuously performed for a predetermined time. A timer T2 for determining whether or not it is held is set (ST8). That is, first, it is determined whether or not the timer T2 is set (ST7). If the timer T2 is not set, the timer T2 is set (ST8). In this case, it is needless to say that the timer T2 is a period shorter than the detection period T1 and is also shorter than the size of the envelope being passed. If the photo sensor 42 does not detect the double feed during the double feed detection period (ST4), the driving of all the rollers is stopped after a lapse of a predetermined time T1 from the start of driving each roller (ST5).

If it is determined that the photo sensor 42 has detected the double feed state continuously during the timer T2 period (ST
9) The multi-feed status indicating "multi-feed" is set in the status information for notifying the printer body (ST10). Finally, by reading the multi-feed status into the printer main body, the printer main body can recognize that multi-feed has occurred inside the envelope feeder. By setting this double feed status on the status that is constantly monitored by the printer main body, the occurrence of double feed is immediately recognized by the printer main body, and the conveyance of the envelope is stopped. <Second Embodiment> Next, a second embodiment of the present invention will be described with reference to FIG.

In this embodiment, the double feed detecting mechanism of the envelope is not performed by the mechanism of the lever 41 and the photosensor 42 as in the first embodiment, but as a generally used distance measuring means. Is performed by the distance measuring sensor 44.

Hereinafter, a configuration using a generally used distance measuring sensor will be described.

In the first embodiment, the movement amount of the transport roller 26b is detected by the lever 41, whereas in the present embodiment, the distance of the reference surface formed on the transport roller holder 26c is directly measured by the distance measuring sensor 44. , Envelope feeder control unit 2
4a.

The distance measuring sensor 44 is a sensor that emits infrared light or the like, irradiates the light to an object to be measured, and measures the reflected light of the object to measure the distance.

The distance measuring sensor 44 includes a type that outputs a 1/0 digital signal for a predetermined distance and a type that outputs an analog signal.

In the present invention, these are not particularly limited. In the case of a digital signal, the threshold value is set to a value at the time of detection of a predetermined double feed, so that the same as in the first embodiment described above. Function can be realized.

On the other hand, when outputting an analog signal,
The result of A / D conversion is processed / determined in the envelope feeder control unit 24a, and the result is transmitted to the printer main body as multi-feed information, or transmitted to the printer main body as A / D exchanged multi-value thickness information. It is also possible.

In any case, the functions and effects of the present invention can be sufficiently exhibited. <Third Embodiment> Next, a third embodiment will be described.

In the third embodiment of the present invention, a description will be given of the processing of the printer main body when multi-feed information is received from the optional envelope feeder 24.

As described in the first embodiment, the printer main body can recognize the multi-feed information from the status information of the serial communication by the optional envelope feeder 24.

Therefore, the optional envelope feeder 24
When a request is made to feed a sheet and printing is performed, status information including a multifeed status is always read.

When the multi-feed information is received from the optional envelope feeder 24, the conveyance of the envelope is stopped before the fed multi-feed envelope reaches the transfer area of the printer main body.

FIG. 9 is a flowchart showing an outline of the processing on the printer main body side.

Upon receiving a print request from the envelope feeder control unit 24a based on a controller (not shown) (ST12), the printer body issues a paper feed start command to the optional envelope feeder 24. Thereby, the first
As shown in the embodiment, the envelope feeder control unit 24
“a” starts the internal paper feeding operation. The printer main body constantly monitors the multi-feed status from the optional envelope feeder 24 by a serial communication operation (not shown). When the multi-feed status becomes "1" (ST18), the printer main body is immediately supplied to the optional envelope feeder 24. Request paper stop (S
At the same time as T19), the printing operation of the printer body is immediately stopped (ST20). Due to this stop operation, the multi-fed envelope stops at a position where it does not reach the transfer nip where the photosensitive drum 1 and the transfer roller 19 abut.

In this case, the notification to the controller (not shown) may be either a jam or a double feed. In any case, since the envelope has not reached the transfer nip portion, it can be used for printing if the user sets it again on the envelope feeder. <Fourth Embodiment> Next, referring to FIG.
An embodiment will be described.

In the fourth embodiment of the present invention, the printer main body is connected to the fixing device 20 based on the thickness information from the envelope feeder.
The case where the temperature control is switched will be described.

FIG. 10 is a diagram schematically showing how the temperature control is changed based on the thickness information obtained from the envelope feeder.

The envelope feeder described here is assumed to have at least two levels of thickness detection functions of L1 and L2. Here, it is assumed that analog thickness detection can be performed for the regions L1 and L2.

Under these conditions, the printer main body is in the area where it is determined that normal envelopes are fed one by one during the period up to the predetermined thickness L1, and the fixing temperature is controlled at the same temperature as normal. doing.

The analog detection areas L1 and L2 are areas where it is determined that an unusual special type of envelope, for example, a particularly thick envelope, is being conveyed. In this area, printing is performed without impairing the fixing property by increasing the fixing temperature according to the thickness.

When it is determined that the envelope feeder has a thickness of L2 or more, it is determined that the envelopes are multi-fed. In this region multifeed by controlling the fixing temperature so that the temperature does not rise more than necessary in the non-paper feed area lower than the normal fixing temperature T ₀ of the fuser 20 of the envelope.

As described above, by lowering the fixing temperature at the time of double feeding, the temperature rise in the non-sheet passing area of the fixing unit 20 is suppressed, and the fixing unit 2
The temperature of each part of 0 can be prevented from rising more than necessary, and the reliability as an electrophotographic printer can be secured.

In the above-described embodiment, the condition is that the territories L1 and L2 are at the analog detection level. This is, for example, to ensure the reliability at the time of double feeding even if L1 = L2. The same effect can be obtained.

[0067] Also, if an envelope feeder for detecting the thickness of the L1 and L2 digitally is, T _n = T _2> T
It goes without saying that the same effect can be obtained by controlling the temperature to ₀ .

[0068]

As is apparent from the above description, according to the present invention, the feeding unit is provided with a thickness detecting means for detecting the thickness of the recording material, and the recording material is supplied from the feeding unit to the printer body. At the time of feeding, the driving unit of the feeding unit is stopped or the fixing temperature of the fixing unit is switched and controlled via the control unit based on the detection signal from the thickness detecting unit. Prevents transport failures during multi-feeding of materials and eliminates waste of multi-fed recording materials, enables appropriate printer control according to the thickness of recording materials, and maintains print quality for image formation. The accompanying usability and reliability can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a functional block diagram for controlling a print engine of the image forming apparatus.

FIG. 3 is a block diagram illustrating a configuration of a communication portion between an option communication control unit and each option feeding unit according to the present embodiment.

FIG. 4 is a diagram illustrating internal information regarding STATUS0 as an example of a status from the envelope feeder to the printer main body.

FIG. 5 is a schematic configuration diagram showing the inside of an optional envelope feeder.

FIG. 6 is a perspective view illustrating a functional configuration of a double feed detecting unit according to the first embodiment.

FIG. 7 is a flowchart illustrating a double feed detection method inside the envelope feeder control unit according to the first embodiment.

FIG. 8 is a schematic configuration diagram of a double feed detection unit according to a second embodiment.

FIG. 9 is a flowchart illustrating an outline of processing on a printer main body side according to the third embodiment.

FIG. 10 is a characteristic diagram illustrating a relationship between the thickness information of the envelope feeder and the temperature of the fixing device according to the fourth embodiment.

FIG. 11 is a schematic configuration diagram illustrating an example of a conventional image forming apparatus.

FIG. 12 is a functional block diagram for controlling a conventional print engine.

FIG. 13 is a block diagram showing a configuration of a communication part between a conventional option communication control unit and each option feeding unit.

FIG. 14 is a time chart showing exchange of a time-sequential sequential command and status in a communication portion between an option communication control unit and each option feeding unit.

[Explanation of symbols]

 Reference Signs List 20 fixing means (fixing device) 24 feeding unit 24a control means (envelope feeder control section) 24b driving section 24c thickness detecting means (double feed detecting section) 26 transport member (envelope transport roller) 44 distance measuring means (distance measuring sensor) 107 Notification means (optional communication control unit)

Claims (6)

[Claims] 1. A feeding unit detachably mounted so as to supply a thick recording material on which a toner image is formed to a printer body, and feeding the recording material from the feeding unit to an image forming unit. And a unit control unit for controlling each unit of the printer engine that forms a toner image on the image forming unit, and fixes the toner image transferred from the image forming unit to the recording material by a fixing unit. In the image forming apparatus, a thickness detecting unit provided in the feeding unit and detecting a thickness of the recording material fed to the printer main body, and fixing the fixing unit based on a detection signal from the thickness detecting unit. Control means for controlling a temperature or a drive unit of the feeding unit. 2. The control means determines that the thick recording material has been multi-fed when the detection signal from the thickness detecting means is information indicating that the recording material is thicker than a preset thickness of the recording material. The image forming apparatus according to claim 1, wherein the feeding of the recording material is stopped. 3. The image forming apparatus according to claim 2, wherein the control unit stops feeding before the recording material reaches an image forming unit of the printer body. 4. The printer according to claim 1, wherein the thickness information communicated to the printer main body based on a detection signal from the thickness detector is such that the thickness of the recording material fed to the printer main body is less than two, If the recording material is thicker than one of the recording materials, it is determined that a recording material thicker than the thicker recording material has been fed, and the fixing temperature is increased. 2. The image forming apparatus according to claim 1, wherein when the number of sheets is two or more, it is determined that the thick recording material has been multi-fed and switching control is performed so as to lower the fixing temperature. 5. The optical disc drive according to claim 1, wherein said thickness detecting means detects a deviation of the conveying member provided in the feeding unit as the recording material passes, and a deviation of the conveying member detected by the optical detecting means. And notifying means for notifying as thickness information when is larger than a predetermined value.
The image forming apparatus as described in the above. 6. A distance measuring means for measuring that a position of a conveying member provided in a feeding unit is deviated as the recording material passes, and said thickness detecting means is measured by said distance measuring means. 5. An informing means for comparing the distance information and the threshold information and informing the thickness information, wherein the informing means is provided.
The image forming apparatus as described in the above.