JP2004252080A - Fixing jamming detector and image forming apparatus provided with it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fixing jamming detector with which the detection of an accordion jamming and a jamming of remaining paper or the like caused in a fixing device can be surely and inexpensively realized in a reduced space, and an image forming apparatus provided with it. <P>SOLUTION: The image forming apparatus has a fixing jamming detection unit 201 to detect that recording paper ejected in the state of being deformed and bent in a fixing unit by which toner is fixed on the recording paper or recording paper ejected from the fixing device is detected near the recording paper ejection side of the fixing unit, and is characterized in that a control circuit 109 stops the operation of the fixing unit in accordance with the detected state of the fixing jamming detection unit 201, and also jamming is displayed on a display device 501. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a fixing jam detecting device that detects a fixing jam and an image forming apparatus including the same.
[0002]
[Prior art]
2. Description of the Related Art A conventional image forming apparatus (a printer, a facsimile, a copying machine, or the like) includes a fixing device for fixing a toner image transferred onto a recording sheet to the recording sheet. This fixing device has a heating roller for thermally melting the toner on the recording paper, and a pressure roller for pressing the recording paper by pressing against the heating roller.
[0003]
Then, a paper passage detection sensor for detecting the recording paper discharged from the fixing device is attached near the recording paper discharge side of the fixing device, and detects a jam occurring in the fixing device. (For example, see Patent Document 1).
[0004]
Further, in order to detect a wrapping jam with respect to the heating roller and a paper jam in the fixing device, a paper detection sensor for detecting the swing of a separation claw for separating the recording paper from the heating roller and a passage for the discharged recording paper are detected. A paper passage detection sensor is attached. (For example, see Patent Document 2).
[0005]
[Patent Document 1]
JP 2000-344395 A (FIG. 1)
[Patent Document 2]
JP-A-2002-82562 (FIG. 2)
[0006]
[Problems to be solved by the invention]
However, such a conventional technique has the following problems.
[0007]
That is, (1) the recording paper wrapped around the heating roller is peeled off by the separation claw, or (2) the recording paper collides with the surrounding frame due to the curl of the recording paper when the recording paper is extruded from the fixing device. In such a case, a jam (hereinafter, referred to as “accordion jam”) that is discharged from the fixing device in a state where the recording paper is complicatedly bent and deformed into a bellows shape of an accordion may occur. When the accordion jam occurs, the deformed recording paper hits a recording paper conveyance guide or the like provided near the discharge side of the fixing device and conveys while suppressing curl of the recording paper, and reaches the position of the paper passage detection sensor. The situation that cannot be done arises. In order to avoid such a situation, it is conceivable to attach the paper passage detection sensor to the paper ejection side of the fixing device. However, a recording paper conveyance guide is provided near the paper ejection side of the fixing device. Difficult in relationship.
[0008]
In such a case, since the recording paper does not reach the position of the paper passage detection sensor, a jam in the fixing device is detected, and the jam is displayed on a display unit or the like. The operator looks at this display and opens the door of the image forming apparatus to search for and remove accordion jam paper (hereinafter, referred to as “jam paper”) in the fixing device. However, the fixing device is usually heated to a high temperature, and the periphery thereof is covered with a cover. For this reason, the operator cannot easily find the jammed paper in the fixing device. In this case, the operator regards the erroneous detection of jammed paper in the image forming apparatus and closes the door without removing the jammed paper.
[0009]
When the door is closed without removing the jammed paper, no jammed paper exists in the detection area of the sensor, and thus the jammed paper cannot be continuously detected on the main body side of the image forming apparatus. For this reason, there has been a problem that it is considered that the jammed paper has been removed and the operable state is set.
[0010]
The present invention has been made in view of such a problem, and a fixing jam detecting apparatus and a fixing jam detecting apparatus capable of reliably detecting accordion jams, remaining paper jams, and the like generated in a fixing device with low cost and space. It is an object of the present invention to provide an image forming apparatus provided with this.
[0011]
[Means for Solving the Problems]
The present invention detects the passage of recording paper discharged in a state of being deformed and bent in the fixing device or recording paper discharged from the fixing device in the vicinity of a recording paper discharge side of a fixing device that fixes toner on the recording paper. The operation of the fixing device is stopped according to the detection state of the detection means, or the display means displays a jam.
[0012]
According to the invention, the passage of the recording paper discharged from the fixing device or the recording paper discharged from the fixing device is detected by the detecting unit disposed near the recording paper discharge side of the fixing device. Since detection can be performed, detection of accordion jam, remaining paper jam, and the like occurring in the fixing device can be realized reliably, at low cost, and in a small space.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
The fixing jam detecting device according to the first aspect of the present invention includes a fixing device for fixing toner on a recording sheet, in the vicinity of a recording sheet discharge side of the fixing device, a recording sheet discharged in a deformed and bent state in the fixing device or A configuration including a detection unit that detects the passage of the recording paper discharged from the fixing device is adopted.
[0014]
According to this configuration, the passage of the recording paper discharged from the fixing device or the recording paper discharged from the fixing device is detected by the detection unit disposed near the recording paper discharge side of the fixing device. Since detection can be performed, detection of accordion jam, remaining paper jam, and the like occurring in the fixing device can be realized reliably, at low cost, and in a small space.
[0015]
A fixing jam detecting device according to a second aspect of the present invention is configured to fix a recording sheet discharged in a deformed and bent state in the fixing device to a vicinity of a recording sheet discharge side of a fixing device for fixing toner on recording paper. A first actuator that is pressed and rotated, a second actuator that is rotated by the passage of recording paper discharged from the fixing device, and a rotation state of the first and second actuators is detected. And a detecting means.
[0016]
According to this configuration, the rotation of the first actuator is detected by the detecting means disposed near the recording paper discharge side of the fixing device, and the recording paper discharged in a deformed and bent state in the fixing device is detected. On the other hand, since the rotation of the second actuator can be detected and the passage of the recording paper discharged from the fixing device can be detected, it is possible to detect the accordion jam and the remaining paper jam generated in the fixing device. Can be realized reliably and at low cost and space saving.
[0017]
A third aspect of the present invention, in the fixing jam detection device according to the second aspect, employs a configuration in which the second actuator is attached to the first actuator.
[0018]
According to this configuration, since the second actuator is attached to the first actuator, the rotation of the second actuator is also detected via the first actuator, so that it is necessary for the second actuator. Space can be reduced. As a result, it is possible to reliably detect accordion jams, remaining paper jams, and the like that occur in the fixing device at low cost and in a small space.
[0019]
According to a fourth aspect of the present invention, in the fixing jam detecting device according to the second or third aspect, the first actuator employs a configuration also serving as a conveyance guide for recording paper discharged from the fixing device.
[0020]
According to this configuration, since the first actuator also serves as a recording paper conveyance guide, there is no need to separately provide a conveyance guide. As a result, it is possible to reliably detect accordion jams, remaining paper jams, and the like that occur in the fixing device at low cost and in a small space.
[0021]
According to a fifth aspect of the present invention, in the fixing jam detection device according to the fourth aspect, the first actuator is biased against a rotating direction by being pushed by a recording sheet discharged from the fixing device. A configuration that is biased by means is adopted.
[0022]
According to this configuration, when the recording paper is conveyed to the second actuator by the first actuator near the recording paper discharge side of the fixing device, even if the leading end of the recording paper tries to push up the first actuator, the urging means is used. As a result, it is possible to reliably prevent the detecting means from malfunctioning and to smoothly carry the recording paper.
[0023]
According to a sixth aspect of the present invention, in the fixing jam detecting device according to the fifth aspect, the urging unit is configured to perform a pressing operation when pressed by a recording sheet discharged from the fixing device in a deformed and bent state. A configuration for rotating one actuator is adopted.
[0024]
According to this configuration, the first actuator is rotated when pressed by the recording paper discharged in a state of being deformed and bent from the fixing device, while being pressed by the recording paper discharged in an undeformed state. In this case, the rotation of the first actuator is limited, so that the conveyance of the recording sheet and the detection of the jam can be reliably performed.
[0025]
A fixing jam detecting device according to a seventh aspect of the present invention is provided near a recording paper discharge side of a fixing device that fixes toner on recording paper, and is a recording paper that is deformed and bent in the fixing device and discharged. A detecting unit for detecting the passage of the recording paper discharged from the fixing device; and a case where the detecting unit detects that the recording paper is discharged in a folded state, and the recording paper does not pass through the detecting unit. And a control unit for stopping the operation of the fixing device in a case where the fixing device is operated.
[0026]
According to this configuration, the passage of the recording paper discharged from the fixing device or the recording paper discharged from the fixing device is detected by the detection unit disposed near the recording paper discharge side of the fixing device. Since detection can be performed, detection of accordion jam, remaining paper jam, and the like occurring in the fixing device can be realized reliably, at low cost, and in a small space.
[0027]
Further, the control means stops the operation of the fixing device when detecting that the recording paper is discharged in a folded state and when the recording paper does not pass through the detection means. On the other hand, as long as the recording paper that caused the jam of the fixing device is not removed, the detecting unit disposed near the recording paper discharge side of the fixing device continues to detect this state. For this reason, since the fixing device is not operated as long as this state is continued, it is possible to prevent the abnormal operation from expanding when a jam occurs.
[0028]
A fixing jam detecting apparatus according to an eighth aspect of the present invention is configured to detect a recording sheet discharged in a state of being deformed and bent in the fixing apparatus in the vicinity of a recording sheet discharge side of a fixing apparatus for fixing toner on recording paper. A first actuator that is pressed and rotated, a second actuator that is rotated by the passage of recording paper discharged from the fixing device, and a rotation state of the first and second actuators is detected. Detection means, and control means for stopping the operation of the fixing device when the detection means detects that the recording paper is discharged in a folded state and when the recording paper does not pass through the detection means, Is adopted.
[0029]
According to this configuration, the rotation of the first actuator is detected by the detecting means disposed near the recording paper discharge side of the fixing device, and the recording paper discharged in a deformed and bent state in the fixing device is detected. On the other hand, since the rotation of the second actuator can be detected and the passage of the recording paper discharged from the fixing device can be detected, it is possible to detect the accordion jam and the remaining paper jam generated in the fixing device. Can be realized reliably and at low cost and space saving.
[0030]
Further, the control means stops the operation of the fixing device when detecting that the recording paper is discharged in a folded state and when the recording paper does not pass through the detection means. On the other hand, as long as the recording paper that caused the jam of the fixing device is not removed, the detecting unit disposed near the recording paper discharge side of the fixing device continues to detect this state. For this reason, since the fixing device is not operated as long as this state is continued, it is possible to prevent the abnormal operation from expanding when a jam occurs.
[0031]
A ninth aspect of the present invention, in the fixing jam detection device according to the eighth aspect, employs a configuration in which the second actuator is attached to the first actuator.
[0032]
According to this configuration, since the second actuator is attached to the first actuator, the rotation of the second actuator is also detected via the first actuator, so that it is necessary for the second actuator. Space can be reduced. As a result, it is possible to reliably detect accordion jams, remaining paper jams, and the like that occur in the fixing device at low cost and in a small space.
[0033]
A fixing jam detecting device according to a tenth aspect of the present invention is provided near a recording paper discharge side of a fixing device for fixing toner on recording paper, and the recording paper is discharged in a state of being deformed and bent in the fixing device. A detecting unit for detecting the passage of the recording paper discharged from the fixing device; and a case where the detecting unit detects that the recording paper is discharged in a folded state, and the recording paper does not pass through the detecting unit. And a display unit for performing a jam display when a jam occurs.
[0034]
According to this configuration, the passage of the recording paper discharged from the fixing device or the recording paper discharged from the fixing device is detected by the detection unit disposed near the recording paper discharge side of the fixing device. Since detection can be performed, detection of accordion jam, remaining paper jam, and the like occurring in the fixing device can be realized reliably, at low cost, and in a small space.
[0035]
Further, the display means displays a jam when the recording paper is detected to be discharged in a folded state and when the recording paper does not pass through the detecting means. On the other hand, as long as the recording paper that caused the jam of the fixing device is not removed, the detecting unit disposed near the recording paper discharge side of the fixing device continues to detect this state. For this reason, the jam display does not disappear on the display means as long as this state continues, and it is possible to reliably notify the operator of the occurrence of the jam, and since the display continues until the jam is released, the jam clearing operation is performed. Can be instructed reliably.
[0036]
A fixing jam detecting device according to an eleventh aspect of the present invention is configured to fix a recording paper discharged in a state of being deformed and bent in the fixing device near a recording paper discharge side of a fixing device for fixing toner on recording paper. A first actuator that is pressed and rotated, a second actuator that is rotated by the passage of recording paper discharged from the fixing device, and a rotation state of the first and second actuators is detected. A detecting means, and a display means for displaying a jam when the detecting means detects that the recording paper is discharged in a folded state and when the recording paper does not pass through the detecting means. take.
[0037]
According to this configuration, the rotation of the first actuator is detected by the detecting means disposed near the recording paper discharge side of the fixing device, and the recording paper discharged in a deformed and bent state in the fixing device is detected. On the other hand, since the rotation of the second actuator can be detected and the passage of the recording paper discharged from the fixing device can be detected, it is possible to detect the accordion jam and the remaining paper jam generated in the fixing device. Can be realized reliably and at low cost and space saving.
[0038]
Further, the display means displays a jam when the recording paper is detected to be discharged in a folded state and when the recording paper does not pass through the detecting means. On the other hand, as long as the recording paper that caused the jam of the fixing device is not removed, the detecting unit disposed near the recording paper discharge side of the fixing device continues to detect this state. For this reason, the jam display does not disappear on the display means as long as this state continues, and it is possible to reliably notify the operator of the occurrence of the jam, and since the display continues until the jam is released, the jam clearing operation is performed. Can be instructed reliably.
[0039]
A twelfth aspect of the present invention, in the fixing jam detecting device according to the eleventh aspect, employs a configuration in which the second actuator is attached to the first actuator.
[0040]
According to this configuration, since the second actuator is attached to the first actuator, the rotation of the second actuator is also detected via the first actuator, so that it is necessary for the second actuator. Space can be reduced. As a result, it is possible to reliably detect accordion jams, remaining paper jams, and the like that occur in the fixing device at low cost and in a small space.
[0041]
An image forming apparatus according to a thirteenth aspect of the present invention is configured such that a recording paper discharged in a deformed and folded state in the fixing device is provided near a recording paper discharge side of a fixing device for fixing toner on the recording paper. A configuration including a detection unit that detects passage of the recording paper discharged from the fixing device is employed.
[0042]
According to this configuration, the passage of the recording paper discharged from the fixing device or the recording paper discharged from the fixing device is detected by the detection unit disposed near the recording paper discharge side of the fixing device. Since detection can be performed, detection of accordion jam, remaining paper jam, and the like occurring in the fixing device can be realized reliably, at low cost, and in a small space.
[0043]
An image forming apparatus according to a fourteenth aspect of the present invention is characterized in that a fixing device for fixing toner on recording paper is pressed against a recording paper discharged in a state of being bent and deformed in the fixing device in the vicinity of a recording paper discharge side. A first actuator that is rotated by rotation, a second actuator that is rotated by the passage of recording paper discharged from the fixing device, and a detection that detects a rotation state of the first actuator and the second actuator. Means is provided.
[0044]
According to this configuration, the rotation of the first actuator is detected by the detecting means disposed near the recording paper discharge side of the fixing device, and the recording paper discharged in a deformed and bent state in the fixing device is detected. On the other hand, since the rotation of the second actuator can be detected and the passage of the recording paper discharged from the fixing device can be detected, it is possible to detect the accordion jam and the remaining paper jam generated in the fixing device. Can be realized reliably and at low cost and space saving.
[0045]
A fifteenth aspect of the present invention, in the image forming apparatus according to the fourteenth aspect, adopts a configuration in which the second actuator is attached to the first actuator.
[0046]
According to this configuration, since the second actuator is attached to the first actuator, the rotation of the second actuator is also detected via the first actuator, so that it is necessary for the second actuator. Space can be reduced. As a result, it is possible to reliably detect accordion jams, remaining paper jams, and the like that occur in the fixing device at low cost and in a small space.
[0047]
A sixteenth aspect of the present invention, in the image forming apparatus according to the fourteenth or fifteenth aspect, adopts a configuration in which the first actuator doubles as a conveyance guide for recording paper discharged from the fixing device.
[0048]
According to this configuration, since the first actuator also serves as a recording paper conveyance guide, there is no need to separately provide a conveyance guide. This makes it possible to reliably detect accordion jams, remaining paper jams, and the like that occur in the fixing device with low cost and space.
[0049]
A seventeenth aspect of the present invention is the image forming apparatus according to the sixteenth aspect, wherein the first actuator is a biasing unit that is pressed against a recording sheet discharged from the fixing device and resists a rotating direction. Is adopted.
[0050]
According to this configuration, when the recording paper is conveyed to the second actuator by the first actuator near the recording paper discharge side of the fixing device, even if the leading end of the recording paper tries to push up the first actuator, the urging means is used. As a result, it is possible to reliably prevent the detecting means from malfunctioning and to smoothly feed the recording paper.
[0051]
An eighteenth aspect of the present invention is directed to the image forming apparatus according to the seventeenth aspect, wherein the urging unit is configured to perform the first operation when the urging unit is pressed by a recording sheet discharged from the fixing device in a deformed and bent state. In which the actuator is rotated.
[0052]
According to this configuration, the first actuator is rotated when pressed by the recording paper discharged in a state of being deformed and bent from the fixing device, while being pressed by the recording paper discharged in an undeformed state. In this case, the rotation of the first actuator is limited, so that the conveyance of the recording sheet and the detection of the jam can be reliably performed.
[0053]
An image forming apparatus according to a nineteenth aspect of the present invention is provided near a recording paper discharge side of a fixing device that fixes toner on recording paper, and a recording paper discharged in a state of being deformed and bent in the fixing device. Detecting means for detecting the passage of the recording paper discharged from the fixing device; and detecting when the detecting means detects that the recording paper is discharged in a bent state, and when the recording paper does not pass through the detecting means. A control means for stopping the operation of the fixing device in such a case.
[0054]
According to this configuration, the passage of the recording paper discharged from the fixing device or the recording paper discharged from the fixing device is detected by the detection unit disposed near the recording paper discharge side of the fixing device. Since detection can be performed, detection of accordion jam, remaining paper jam, and the like occurring in the fixing device can be realized reliably, at low cost, and in a small space.
[0055]
Further, the control means stops the operation of the fixing device when detecting that the recording paper is discharged in a folded state and when the recording paper does not pass through the detection means. On the other hand, as long as the recording paper that caused the jam of the fixing device is not removed, the detecting unit disposed near the recording paper discharge side of the fixing device continues to detect this state. For this reason, since the fixing device is not operated as long as this state is continued, it is possible to prevent the abnormal operation from expanding when a jam occurs.
[0056]
An image forming apparatus according to a twentieth aspect of the present invention is configured such that a recording paper discharged in a state of being deformed and bent in the fixing device is disposed near a recording paper discharge side of a fixing device for fixing toner on recording paper. A first actuator that is rotated by rotation, a second actuator that is rotated by the passage of recording paper discharged from the fixing device, and a detection that detects a rotation state of the first actuator and the second actuator. Control means for stopping the operation of the fixing device when the detection means detects that the recording paper has been discharged in a folded state and when the recording paper has not passed through the detection means. The configuration provided is adopted.
[0057]
According to this configuration, the rotation of the first actuator is detected by the detecting means disposed near the recording paper discharge side of the fixing device, and the recording paper discharged in a deformed and bent state in the fixing device is detected. On the other hand, since the rotation of the second actuator can be detected and the passage of the recording paper discharged from the fixing device can be detected, it is possible to detect the accordion jam and the remaining paper jam generated in the fixing device. Can be realized reliably and at low cost and space saving.
[0058]
Further, the control means stops the operation of the fixing device when detecting that the recording paper is discharged in a folded state and when the recording paper does not pass through the detection means. On the other hand, as long as the recording paper that caused the jam of the fixing device is not removed, the detecting unit disposed near the recording paper discharge side of the fixing device continues to detect this state. For this reason, since the fixing device is not operated as long as this state continues, it is possible to prevent the abnormal operation from expanding in the event of a jam.
[0059]
A twenty-first aspect of the present invention, in the image forming apparatus according to the twentieth aspect, adopts a configuration in which the second actuator is attached to the first actuator.
[0060]
According to this configuration, since the second actuator is attached to the first actuator, the rotation of the second actuator is also detected via the first actuator, so that it is necessary for the second actuator. Space can be reduced. This makes it possible to reliably detect accordion jams, remaining paper jams, and the like that occur in the fixing device with low cost and space.
[0061]
An image forming apparatus according to a twenty-second aspect of the present invention is provided near a recording paper discharge side of a fixing device for fixing toner on recording paper, wherein the recording paper is deformed and bent in the fixing device and discharged. Detecting means for detecting the passage of the recording paper discharged from the fixing device; and detecting when the detecting means detects that the recording paper is discharged in a bent state, and when the recording paper does not pass through the detecting means. And a display means for displaying a jam in a case.
[0062]
According to this configuration, the passage of the recording paper discharged from the fixing device or the recording paper discharged from the fixing device is detected by the detection unit disposed near the recording paper discharge side of the fixing device. Since detection can be performed, detection of accordion jam, remaining paper jam, and the like occurring in the fixing device can be realized reliably, at low cost, and in a small space.
[0063]
Further, the display means displays a jam when the recording paper is detected to be discharged in a folded state and when the recording paper does not pass through the detecting means. On the other hand, as long as the recording paper that caused the jam of the fixing device is not removed, the detecting unit disposed near the recording paper discharge side of the fixing device continues to detect this state. For this reason, the jam display does not disappear on the display means as long as this state continues, and it is possible to reliably notify the operator of the occurrence of the jam, and since the display continues until the jam is released, the jam clearing operation is performed. Can be instructed reliably.
[0064]
An image forming apparatus according to a twenty-third aspect of the present invention is arranged such that a recording paper discharged in a state of being deformed and bent in the fixing device is disposed near a recording paper discharge side of a fixing device for fixing toner on recording paper. A first actuator that is rotated by rotation, a second actuator that is rotated by the passage of recording paper discharged from the fixing device, and a detection that detects a rotation state of the first actuator and the second actuator. Means, and a display means for displaying a jam when the recording paper is detected to be discharged in a folded state and when the recording paper does not pass through the detection means. .
[0065]
According to this configuration, the rotation of the first actuator is detected by the detecting means disposed near the recording paper discharge side of the fixing device, and the recording paper discharged in a deformed and bent state in the fixing device is detected. On the other hand, since the rotation of the second actuator can be detected and the passage of the recording paper discharged from the fixing device can be detected, it is possible to detect the accordion jam and the remaining paper jam generated in the fixing device. Can be realized reliably and at low cost and space saving.
[0066]
Further, the display means displays a jam when the recording paper is detected to be discharged in a folded state and when the recording paper does not pass through the detecting means. On the other hand, as long as the recording paper that caused the jam of the fixing device is not removed, the detecting unit disposed near the recording paper discharge side of the fixing device continues to detect this state. For this reason, the jam display does not disappear on the display means as long as this state continues, and it is possible to reliably notify the operator of the occurrence of the jam, and since the display continues until the jam is released, the jam clearing operation is performed. Can be instructed reliably.
[0067]
A twenty-fourth aspect of the present invention, in the image forming apparatus according to the twenty-third aspect, employs a configuration in which the second actuator is attached to the first actuator.
[0068]
According to this configuration, since the second actuator is attached to the first actuator, the rotation of the second actuator is also detected via the first actuator, so that it is necessary for the second actuator. Space can be reduced. As a result, it is possible to reliably detect accordion jams, remaining paper jams, and the like that occur in the fixing device at low cost and in a small space.
[0069]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0070]
FIG. 1 is a block diagram showing a schematic configuration of an image forming apparatus provided with a fixing jam detecting device according to an embodiment of the present invention.
[0071]
As shown in FIG. 1, the image forming apparatus 100 according to the present embodiment takes out recording paper from a paper feed cassette 101 provided on the bottom of the apparatus, and sends the recording paper to a process unit 102 disposed above the paper feed cassette 101. Send in. The process unit 102 includes a photosensitive drum 104 on which a latent image is formed by a laser scan unit (hereinafter, referred to as “LSU (Laser Scan Unit)”) 103, and an image obtained by attaching toner to the latent image is formed. Transfer to recording paper.
[0072]
The recording paper on which the image has been transferred is sent to a fixing unit 105 arranged above the process unit 102. The fixing unit 105 includes a heating roller 106 that applies heat to the recording paper, and a pressure roller 107 that applies a constant pressure to the heating roller 106, and fixes the image transferred to the recording paper.
[0073]
A sensor 108 is provided at a position where the recording paper sent from the heating roller 106 and the pressure roller 107 is detected. The sensor 108 operates together with a fixing jam detecting unit, which will be described later, to prevent the recording sheet from being conveyed (hereinafter, referred to as “unreachable jam”) in the image forming apparatus 100 or to cause the fixing unit 105 to detect a recording sheet. The remaining jam (hereinafter referred to as “remaining paper jam”) and the accordion jam are detected. The recording paper on which the image is fixed and discharged from the fixing unit 105 is discharged outside the apparatus by a transport system (not shown).
[0074]
The control of the components included in the image forming apparatus 100 is performed by the control circuit 109. Specifically, the control circuit 109 gives the image information of the document read by the scanner 110 to the LSU 103 to form a latent image on the photoconductor 104. In addition, while controlling the fixing unit 105 in accordance with an output signal from the sensor 108, the control unit controls a transport system for discharging the recording paper.
[0075]
Hereinafter, the configuration of the fixing jam detection unit included in fixing unit 105 of image forming apparatus 100 according to the present embodiment will be described. 2 to 4 are enlarged views showing the structure around the fixing jam detection unit provided in the fixing unit 105 of the image forming apparatus 100 according to the present embodiment. 2, 3, and 4 show a side view, a front view, and a perspective view, respectively.
[0076]
The fixing jam detection unit 201 functioning as a detecting unit is provided in the vicinity of the recording paper discharge side of the fixing unit 105. Specifically, as shown in FIGS. 2 to 4, it is provided near the upper portion of the heating roller 106 and the pressing roller 107. The fixing jam detection unit 201 includes a first actuator 202 and a second actuator 203.
[0077]
As shown in FIG. 2, the first actuator 202 is disposed to face a part of the housing 204 that functions as a guide for conveying the recording sheet sent out between the heating roller 106 and the pressure roller 107, and The first actuator 202 itself also functions as a guide for conveying the recording paper. As described above, since the first actuator 202 also functions as a recording paper guide, it is not necessary to separately provide a recording paper guide, thereby realizing space saving in the apparatus.
[0078]
Note that, as shown in FIG. 3, a rib 205 is formed on a portion of the first actuator 202 that functions as a guide. As a result, the fixing jam detection unit 201 is reduced in weight, and good conveyance is realized by reducing the contact with the recording paper.
[0079]
The first actuator 202 is rotatably supported by the housing of the image forming apparatus 100, and is configured to be rotatable in an arrow direction A shown in FIG. In addition, as shown in FIG. 4, one end of a coil spring 206 as an urging means is attached to the first actuator 202 near the end. The other end of the coil spring 206 is attached to a casing of the apparatus main body (not shown) and urges the first actuator 202 downward of the apparatus.
[0080]
Since the first actuator 202 is urged downward by the coil spring 206 as described above, it is possible to prevent the sensor 108 from being erroneously operated by being pressed by the recording paper being conveyed. The biasing force of the coil spring 206 is set to such an extent that the first actuator 202 is allowed to rotate when an accordion jam described later occurs. Therefore, when accordion jam occurs, jam detection can be reliably performed.
[0081]
As shown in FIGS. 2 to 4, the second actuator 203 is pivotally supported on a part of the upper surface of the first actuator 202, and is attached so as to be rotatable in the arrow direction B shown in FIG. 2. The second actuator 203 is disposed on a part of the upper surface of the first actuator 202 from the vicinity of the center to the left side (the lower side shown in FIG. 4) shown in FIG. Since the second actuator 203 is attached to the first actuator 202 in this manner, the rotation of the second actuator 203 is also detected via the first actuator 202, so that the space required for the second actuator 203 is reduced. Can be reduced.
[0082]
One end of the second actuator 203 on the left side shown in FIG. 3 (the lower side shown in FIG. 4) protrudes beyond the end of the first actuator 202. At a position protruding from the end of the first actuator 202, the first actuator 202 has a shape bent toward the rear side (the left side in FIG. 4) shown in FIG. The sensor 108 is provided at a position where the tip of the bent portion is accommodated so that the detection region is arranged. Hereinafter, the shape portion accommodated in the detection region of the sensor 108 is referred to as a detected portion 207.
[0083]
On the other hand, the other end of the second actuator 203 has a shape bent in the direction of the first actuator 202. The tip of this bent portion has a shape protruding onto the recording paper transport path from an opening 208 formed near the center of the first actuator 202 shown in FIGS. Hereinafter, the shape portion of the recording paper projecting on the conveyance path is referred to as a passage detection unit 209.
[0084]
FIG. 2 shows a state in which the detected portion 207 of the second actuator 203 is accommodated in the detection area of the sensor 108, and the passage detection portion 209 protrudes on the recording paper conveyance path. As shown in the figure, the detected part 207 extends toward the left side shown in FIG. 2, while the passage detection part 209 is on the left side shown in FIG. It is growing. Thus, when the passage detection unit 209 moves in the direction of arrow B shown in FIG. 2 due to the passage of the recording paper, the detection unit 207 also retreats from the detection area of the sensor 108.
[0085]
Next, the control operation of the control circuit 109 for the fixing jam detection unit 201 having the above configuration will be described. FIG. 5 is a schematic diagram for explaining control of the fixing jam unit in the control circuit of the image forming apparatus according to the present embodiment. FIG. 5 shows a case where accordion jam has occurred in the recording paper fed from the heating roller 106 and the pressure roller 107.
[0086]
As shown in the figure, the control circuit 109 is connected to a driving system (not shown) such as a heating roller in the fixing unit 105, a sensor 108 and a display device 501 as a display unit. Accordingly, the fixing unit 105 and the display device 501 are controlled according to a signal output from the sensor 108. The display device 501 displays, for example, occurrence of a paper jam in the image forming apparatus 100.
[0087]
The control circuit 109 includes a CPU 502 as a control unit that controls the entire image forming apparatus 100, a ROM (Read Only Memory) 503 in which a program read and executed by the CPU 502 is stored, and a RAM (functioning as a work area of the CPU 502). Random Access Memory) 504. When an ON signal is output from the sensor 108 to the control circuit 109 in accordance with the position of the fixing jam detection unit 201, the CPU 502 causes the display device 501 to display that a jam has occurred. Once the CPU 501 receives the output of the ON signal from the sensor 108, the CPU 501 stops the operation of the fixing unit 105 until it receives the output of the OFF signal from the sensor 108.
[0088]
Hereinafter, a paper jam detection operation in the fixing jam detection unit 201 having the above configuration will be described. FIG. 6 and FIG. 7 are schematic diagrams for explaining a paper jam detection operation in the fixing jam detection unit 201 of the image forming apparatus 100 according to the present embodiment. FIG. 6 shows a state in which a paper jam has not occurred in the fixing unit 105, and FIG. 7 shows a state in which a paper jam has occurred in the fixing unit 105.
[0089]
First, a state in which paper jam has not occurred in the fixing unit 105 will be described with reference to FIG.
[0090]
FIG. 6A illustrates a state in which the recording sheet onto which the image has been transferred in the process unit 102 is sent to the fixing unit 105, and the leading end thereof contacts the passage detection unit 209. At this time, since the first actuator 202 is urged downward by the coil spring 206 and no force is applied to the second actuator 203, the detected portion 207 of the second actuator 203 is moved to the detection area of the sensor 108. It is in a housed state.
[0091]
From this state, the recording paper is further conveyed upward by the heating roller 106 and the heating roller 107. In accordance with the conveyance of the recording sheet, the passage detection unit 209 of the second actuator 203 rotates in the direction of arrow B in the figure, and the detection unit 207 also moves upward in response to the rotation. As a result, the detected part 207 is retracted from the detection area of the sensor 108. As a result, an ON signal is output from the sensor 108 to the control circuit 109. When receiving the ON signal, the control circuit 109 recognizes that the recording paper has passed. This state is maintained until the recording paper has passed.
[0092]
FIG. 6B shows a state in which the trailing edge of the recording paper has passed through the detection area of the passage detection unit 209. At this time, the passage detection unit 209 is released from the recording paper, rotates in the direction of arrow C in the figure, and the detection unit 207 also moves downward in response to this. As a result, the state returns to the state in which the detected part 207 is stored in the detection area of the sensor 108 again. As a result, an OFF signal is output from the sensor 108 to the control circuit 109. Upon receiving this OFF signal, the control circuit 109 recognizes that the recording paper has passed.
[0093]
Next, a state in which paper jam has occurred in the fixing unit 105 will be described with reference to FIG.
[0094]
FIG. 7A illustrates a case where a residual paper jam occurs in the fixing unit 105. As shown in the drawing, when a remaining paper jam occurs, the passage detection unit 209 is maintained in a state of being caught on the recording paper. Therefore, the detected part 207 is also maintained in a state of being retracted from the detection area of the sensor 108. In this case, the control circuit 109 outputs an ON signal from the sensor 108 but does not output an OFF signal. As a result, the control circuit 109 recognizes that a residual paper jam has occurred in the fixing unit 105.
[0095]
On the other hand, FIG. 7B shows a case where an accordion jam has occurred in the fixing unit 105. As shown in the drawing, when an accordion jam occurs, a part of the recording paper on which the accordion jam has been formed pushes up the first actuator 202 and turns in the direction of arrow A in the figure. When the first actuator 202 rotates, the second actuator 203 attached to the first actuator 202 moves upward accordingly. For this reason, the detected part 207 also moves upward, and is retracted from the detection area of the sensor 108. As a result, an ON signal is output from the sensor 108 to the control circuit 109, but an OFF signal is not output from the sensor 108 as in the case of remaining paper jam. As a result, the control circuit 109 recognizes that a residual paper jam has occurred in the fixing unit 105.
[0096]
As described above, the fixing jam detection unit 201 arranged near the discharge side of the fixing unit 105 detects the rotation of the first actuator 202 and deforms the recording paper discharged inside the fixing unit 105 in a bent state. While it is possible to detect the rotation of the second actuator 203 and detect the passage of the recording paper discharged from the fixing unit 105, accordion jams and remaining paper jams generated in the fixing unit 105 can be detected. Detection can be realized reliably and at low cost and in a small space.
[0097]
An operation for determining a paper jam that has occurred in the fixing unit 105 will be described. FIG. 8 is a flowchart illustrating an operation of determining a paper jam that has occurred in the fixing unit of the image forming apparatus according to the present embodiment. Such a determination operation is performed in the control circuit 109.
[0098]
When determining the fixing jam, the control circuit 109 determines whether a predetermined time (T1) has elapsed since the image forming apparatus 100 instructed image formation (ST801). The predetermined time (T1) is set to determine the time from when the image formation is instructed to when the recording paper is conveyed to the position to be detected by the sensor 108 in the fixing unit 105.
[0099]
When the predetermined time (T1) has elapsed, control circuit 109 determines an output signal from sensor 108 (ST802). Here, when the output signal from the sensor 108 is an OFF signal (when the output of the ON signal is not received), the control circuit 109 determines that the leading edge of the recording paper has not been conveyed to the detection area of the passage detection unit 209, and displays the display. After displaying the unreachable jam on the device 501 (ST803), the operation of the fixing unit 105 is stopped (ST804). After the operation of the fixing unit 105 is stopped, it is determined that the maintenance opening / closing door provided in the image forming apparatus 100 has been opened and closed, and the same determination processing is performed again.
[0100]
On the other hand, when the output signal from sensor 108 is an ON signal, control circuit 109 determines the elapse of a predetermined time (T2) from the time when the ON signal is received (ST805). The predetermined time (T2) is set to determine the time until the trailing edge of the recording paper passes through the detection area of the passage detection unit 209.
[0101]
When the predetermined time (T2) has elapsed, control circuit 109 determines again the output signal from sensor 108 (ST806). Here, when the output signal from the sensor 108 is an OFF signal, the control circuit 109 determines that the recording paper has passed normally, and ends the processing.
[0102]
On the other hand, if the output signal from the sensor 108 is an ON signal, it is determined that the recording paper has not passed and a remaining paper jam has occurred, or that an accordion jam has occurred, and the unreachable jam is displayed on the display device 501. After that (ST807), the operation of the fixing unit 105 is stopped (ST808). After the operation of the fixing unit 105 is stopped, it is determined that the maintenance opening / closing door provided in the image forming apparatus 100 has been opened and closed, and the same determination processing is performed again.
[0103]
As described above, according to image forming apparatus 100 of the present exemplary embodiment, fixing jam detection unit 201 disposed near the recording sheet discharge side of fixing unit 105 discharges the paper in a state of being deformed and bent in fixing unit 105. To detect accordion jams and remaining paper jams generated in the fixing unit 105 with reliability, low cost, and space saving. Can be.
[0104]
Further, according to the image forming apparatus 100 of the embodiment, the control circuit 109 detects that the recording paper has been discharged in a folded state and that the recording paper has not passed through the fixing jam detection unit 201. Then, the operation of the fixing unit 105 is stopped. On the other hand, unless the recording paper that caused the jam of the fixing unit 105 is removed, the fixing jam detecting unit 201 continues to detect this state. For this reason, since the fixing unit 105 is not operated as long as this state continues, it is possible to prevent the abnormal operation from expanding in the event of a jam.
[0105]
Further, according to the image forming apparatus 100 of the present embodiment, the display device 501 is provided when it is detected that the recording paper is discharged in a folded state and when the recording paper does not pass through the fixing jam detection unit 201. Appears on the screen. On the other hand, unless the recording paper that caused the jam of the fixing unit 105 is removed, the fixing jam detecting unit 201 continues to detect this state. For this reason, the jam display on the display device 501 does not disappear as long as this state continues, so that the operator can be reliably notified of the occurrence of the jam, and the display is continued until the jam is released, so that the jam is released. You can instruct work reliably.
[0106]
【The invention's effect】
As described above, according to the present invention, detection of accordion jams, remaining paper jams, and the like occurring in a fixing device can be realized reliably, at low cost, and in a small space.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a schematic configuration of an image forming apparatus provided with a fixing jam detecting device according to an embodiment of the present invention;
FIG. 2 is an enlarged side view showing a structure around a fixing jam detection unit provided in the fixing unit of the image forming apparatus according to the embodiment.
FIG. 3 is an enlarged front view showing a structure around a fixing jam detection unit provided in the fixing unit of the image forming apparatus according to the embodiment.
FIG. 4 is an enlarged perspective view showing a structure around a fixing jam detection unit provided in the fixing unit of the image forming apparatus according to the embodiment.
FIG. 5 is a schematic diagram illustrating control of a fixing jam detection unit in a control circuit of the image forming apparatus according to the embodiment.
FIG. 6 is a schematic diagram illustrating a paper jam detection operation in the fixing jam detection unit of the image forming apparatus according to the embodiment.
FIG. 7 is a schematic diagram for explaining a paper jam detection operation in the fixing jam detection unit of the image forming apparatus according to the embodiment.
FIG. 8 is a flowchart illustrating an operation of determining a paper jam that has occurred in a fixing unit of the image forming apparatus according to the embodiment.
[Explanation of symbols]
100 Image forming apparatus
101 Paper cassette
102 process unit
105 Fixing unit
108 sensor
109 control circuit
201 Fixing jam detection unit
202 First actuator
203 Second actuator
206 Coil spring
207 Detected part
209 Passage detector
501 Display device

Claims (24)

In the vicinity of the recording paper discharge side of a fixing device for fixing toner on recording paper, detection for detecting passage of recording paper discharged in a state of being deformed and bent in the fixing device or recording paper discharged from the fixing device. A fixing jam detecting device comprising: A first actuator which is rotated by being pressed by a recording sheet discharged in a state where the recording sheet is deformed and bent in the fixing device, in the vicinity of a recording sheet discharge side of the fixing device for fixing toner on the recording sheet; and the fixing device. Fixation jam detection, comprising: a second actuator that rotates when a recording sheet discharged from the printer passes therethrough; and detection means that detects a rotation state of the first actuator and the second actuator. apparatus. The fixing jam detecting device according to claim 2, wherein the second actuator is attached to the first actuator. The fixing jam detecting device according to claim 2, wherein the first actuator also serves as a conveyance guide for recording paper discharged from the fixing device. 5. The fixing jam detecting device according to claim 4, wherein the first actuator is urged by urging means which is pressed against a recording sheet discharged from the fixing device and opposes a rotating direction. 6. The fixing jam detecting apparatus according to claim 5, wherein the urging unit rotates the first actuator when pressed by a recording sheet discharged while being deformed and bent from the fixing device. . It is provided near the recording paper discharge side of a fixing device that fixes toner on recording paper, and detects passage of recording paper discharged from the fixing device or discharged in a state where the recording paper is deformed and bent in the fixing device. Detection means, and control means for stopping the operation of the fixing device when the detection means detects that the recording paper is discharged in a folded state and when the recording paper does not pass through the detection means, A fixing jam detecting device comprising: A first actuator which is rotated by being pressed by a recording sheet discharged in a state where the recording sheet is deformed and bent in the fixing device, in the vicinity of a recording sheet discharge side of the fixing device for fixing toner on the recording sheet; and the fixing device. A second actuator that is rotated by the passage of recording paper discharged from the printer, detection means for detecting the rotation state of the first actuator and the second actuator, and a state in which the recording paper is bent by the detection means And a control unit for stopping the operation of the fixing device when it is detected that the recording paper has been ejected and when the recording paper does not pass through the detection unit. 9. The fixing jam detecting apparatus according to claim 8, wherein the second actuator is attached to the first actuator. It is provided near the recording paper discharge side of a fixing device that fixes toner on recording paper, and detects passage of recording paper discharged from the fixing device or discharged in a state where the recording paper is deformed and bent in the fixing device. A detecting means, and a display means for displaying a jam when the detecting means detects that the recording paper is discharged in a folded state and when the recording paper does not pass through the detecting means. Fixing jam detecting device. A first actuator which is rotated by being pressed by a recording paper discharged in a state of being deformed and bent in the fixing device, near the recording paper discharge side of the fixing device for fixing the toner on the recording paper; and the fixing device. A second actuator that is rotated by the passage of recording paper discharged from the printer, detection means for detecting the rotation state of the first actuator and the second actuator, and a state in which the recording paper is bent by the detection means And a display unit for displaying a jam when the recording paper is detected to have been ejected and when the recording paper does not pass through the detecting unit. The fixing jam detecting device according to claim 11, wherein the second actuator is attached to the first actuator. In the vicinity of the recording paper discharge side of a fixing device for fixing toner on recording paper, detection for detecting passage of recording paper discharged in a state of being deformed and bent in the fixing device or recording paper discharged from the fixing device. An image forming apparatus comprising: A first actuator which is rotated by being pressed by a recording sheet discharged in a state of being deformed and bent in the fixing device, in the vicinity of a recording sheet discharge side of a fixing device for fixing toner on recording paper; and the fixing device. An image forming apparatus comprising: a second actuator that rotates when a recording sheet discharged from the printer passes therethrough; and detection means that detects a rotation state of the first actuator and the second actuator. . The image forming apparatus according to claim 14, wherein the second actuator is attached to the first actuator. 16. The image forming apparatus according to claim 14, wherein the first actuator doubles as a conveyance guide for recording paper discharged from the fixing device. 17. The image forming apparatus according to claim 16, wherein the first actuator is urged by an urging unit that is pressed against a recording sheet discharged from the fixing device and opposes a rotating direction. 18. The image forming apparatus according to claim 17, wherein the urging unit rotates the first actuator when pressed by a recording sheet discharged while being deformed and bent from the fixing device. It is provided near the recording paper discharge side of a fixing device that fixes toner on recording paper, and detects passage of recording paper discharged from the fixing device or discharged in a state where the recording paper is deformed and bent in the fixing device. Detection means, and control means for stopping the operation of the fixing device when the detection means detects that the recording paper is discharged in a folded state and when the recording paper does not pass through the detection means, An image forming apparatus comprising: A first actuator which is rotated by being pressed by a recording sheet discharged in a state where the recording sheet is deformed and bent in the fixing device, in the vicinity of a recording sheet discharge side of the fixing device for fixing toner on the recording sheet; and the fixing device. A second actuator that is rotated by the passage of recording paper discharged from the printer, detection means for detecting the rotation state of the first actuator and the second actuator, and a state in which the recording paper is bent by the detection means A control unit for stopping the operation of the fixing device when it is detected that the recording paper has been ejected and when the recording paper does not pass through the detection unit. The image forming apparatus according to claim 20, wherein the second actuator is attached to the first actuator. It is provided near the recording paper discharge side of a fixing device that fixes toner on recording paper, and detects passage of recording paper discharged from the fixing device or discharged in a state where the recording paper is deformed and bent in the fixing device. A detecting means, and a display means for displaying a jam when the detecting means detects that the recording paper is discharged in a folded state and when the recording paper does not pass through the detecting means. Image forming apparatus. A first actuator which is rotated by being pressed by a recording sheet discharged in a state where the recording sheet is deformed and bent in the fixing device, in the vicinity of a recording sheet discharge side of the fixing device for fixing toner on the recording sheet; and the fixing device. A second actuator that is rotated by the passage of recording paper discharged from the printer, detection means for detecting the rotation state of the first actuator and the second actuator, and a state in which the recording paper is bent by the detection means And a display unit for performing a jam display when it is detected that the recording sheet has been ejected and when the recording paper does not pass through the detection unit. The image forming apparatus according to claim 23, wherein the second actuator is attached to the first actuator.

Images