JP2005091687A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a user from waiting, to prevent long unloading working, and also to prevent an image from deteriorating, by preventing the occurrence of dew condensation at unloading or installing working after product shipment. <P>SOLUTION: The image forming apparatus supplies electric power from a capacitor 149 to a control part 146 and a capacitor charge and discharge circuit 148 when an AC power source is turned off, and supplies the power supplied from a charger 144 to the control part 146 and the capacitor charge and discharge circuit 148 by supplying the AC power when the AC power source is turned on. The capacitor charge and discharge circuit 148 supplies the electric power to dew condensation prevention heaters 154 and 155 by performing discharge operation when depressing a dew condensation prevention switch 151 before a service man ships to the user. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus that forms an image on a recording sheet using optical system components.

  Conventionally, in an image forming apparatus such as a copying machine or a printer, dew condensation occurs on optical parts such as a mirror and a lens provided in a document image reading unit in order to prevent moisture absorption of recording paper in a supply tray. In order to prevent this, a heater of about 5 to 20 W has been provided in the image forming apparatus. Such a dehumidifying heater is often energized when the power is turned off by a relay, or when the power is supplied only to the main controller called the energy saving mode (off mode).

  Also, a technique of installing an auxiliary power source such as an electric double layer capacitor and an auxiliary heater is known in order to assist the power supply to the fixing heater when starting up the image forming apparatus or copying. 2).

JP 2002-280146 A JP-A-5-241387

  However, in such a conventional image forming apparatus, the means shown in Patent Documents 1 and 2 are certainly effective. For example, when the product is shipped, the main switch is turned on immediately after the power outlet is connected. However, the condensation heater cannot remove the condensation, and if the machine warms up or performs a copy operation while the machine is in a condensed state, if the reading mirror is condensed, an image error occurs due to the water droplets on the mirror. was there.

  In addition, when moisture adheres to the photoconductor, there is a problem in that toner does not adhere due to poor charging, and even if it adheres, an image abnormality such as an image being distorted due to moisture on the surface of the photoconductor occurs.

  In addition, if paper separation failure occurs due to paper moisture adhering due to condensation on the transport path or leakage due to condensation on the paper separation charger, there is a problem of causing paper jams. If it occurs, it will lead to suspicious consumers, leading to a downgrading of the product image.

  Therefore, as a method of removing condensation, a method can be considered in which a temperature sensor is provided inside and outside the device to increase the internal temperature of the device when the power is turned on. However, depending on where the temperature sensor is installed, there is an error between the measured temperature and the actual temperature. As a result, there is a possibility that the determination of whether or not the dew condensation state is present, and there is a problem that the cost increases when a plurality of temperature sensors and humidity sensors are mounted.

  In addition, it is of course possible to remove the condensation by energizing the condensation prevention heater at the time of product shipment or turning on the power and leaving the machine for a while in the standby state to remove the condensation. There is a problem that it becomes inefficient because of waiting for a long time, and a long time for arrival of a service person.

  The present invention has been made in view of the above, and prevents the occurrence of condensation at the time of arrival after product shipment or installation work, prevents the user from waiting or lengthening the arrival work, and prevents condensation. An object of the present invention is to provide an image forming apparatus capable of preventing the deterioration of an image as a cause.

  In order to solve the above-described problems and achieve the object, the invention according to claim 1 is an image forming apparatus that forms an image on recording paper using an optical system component, and includes an auxiliary power source that can be charged, And a heat generating member that generates heat when power is supplied from the auxiliary power source, so that power can be supplied from the auxiliary power source to the heat generating member even when the main power of the apparatus main body is not turned on.

  According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, a plurality of the heat generating members are provided inside the apparatus main body, and power is selectively supplied to the plurality of heat generating members from the auxiliary power source. A switching unit that can be supplied is provided.

  According to a third aspect of the present invention, in the image forming apparatus according to the second aspect, the plurality of heat generating members include at least a fixing heater used in the fixing device and a dew condensation prevention heater for preventing dew condensation inside the apparatus main body. One of the power supply destinations is switched according to the usage status by the switching unit.

  According to a fourth aspect of the present invention, in the image forming apparatus according to any one of the first to third aspects, power is being supplied while power is being supplied from the auxiliary power source to the heat generating member. And a notification unit for notifying the operator of the above.

  In order to install the product, the image forming apparatus according to claim 1 can generate heat by supplying power to the heat generating member from the rechargeable auxiliary power supply even when the main power supply of the apparatus main body is not turned on. Before visiting the user, by supplying power from the auxiliary power source to the heat generating member in advance to warm the inside of the machine, it is possible to prevent the occurrence of condensation at the time of arrival and installation work, and to make the user wait There is an effect that it is possible to avoid the problem that the arrival work becomes long.

  In the image forming apparatus according to the second aspect, a plurality of heat generating members are provided inside the apparatus main body, and power can be selectively supplied from the auxiliary power source to the plurality of heat generating members by the switching unit. For this reason, for example, if a heat generating member installed at a location effective for condensation is selected and power is supplied, condensation will occur during arrival and installation work when visiting the user to install the product. It is possible to efficiently prevent the waiting time of the user, and there is an effect that the arrival work can be efficiently performed in a shorter time.

  In the image forming apparatus according to the third aspect, the plurality of heat generating members include at least one of the fixing heater and the dew condensation prevention heater, and the power supply destination is switched by the switching unit according to the use state. In some cases, by supplying power to the anti-condensation heater installed in a location that is effective against dew condensation, it is possible to prevent dew condensation by warming the interior of the machine before visiting the user to install the product. The effect is to prevent. In addition, after the main power supply is turned on, switching the power supply destination to the fixing heater side has an effect of shortening the startup time of the fixing heater as an auxiliary to the main power supply.

  The image forming apparatus according to the fourth aspect includes a notification unit that notifies that the power is being supplied while power is being supplied from the auxiliary power source to the heat generating member. The main power supply (AC power supply) is not supplied, but power can be supplied from the auxiliary power supply to notify that there is a part that is partly hot. There is an effect that can be prevented.

  Embodiments of an image forming apparatus according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

  FIG. 1 is a cross-sectional view illustrating the overall configuration of an image forming apparatus used in the present invention. The image forming apparatus shown in FIG. 1 is a multifunction machine having functions such as a copying machine, a printer, and a facsimile machine. Using an application switching key (not shown), a copying function, a printer function, and a facsimile function are sequentially provided. You can select by switching. That is, the copy mode is selected when the copy function is selected, the print mode is selected when the printer function is selected, and the facsimile mode is selected when the facsimile mode is selected.

  First, an image forming apparatus shown in FIG. 1 includes an automatic document feeder (hereinafter referred to as ADF) 101, a document table 102, a feeding roller 103, a feeding belt 104, a document table 105, an image reading device 106, a discharge roller 107, A paper discharge tray 108, a document set detector 109, a first paper feeder 110, a second paper feeder 111, a third paper feeder 112, a first tray 113, a second tray 114, a third tray 115, a vertical transport unit 116, a photoreceptor 117, a writing unit 118, a developing device 119, a conveyance belt 120, a fixing device 121, a paper discharge unit 122, a paper discharge tray 123, a double-sided input conveyance path 124, a reversing unit 125, a double-sided conveyance unit 126, a reverse discharge. Paper conveyance path 127, light source 128, mirrors 129 to 131, lens 132, image sensor 133, laser light source 134, lens 135, Beauty, and a polygon mirror 136.

  The operation of the image forming apparatus in the copy mode is as follows. In the ADF 101, when a bundle of documents is placed on the document table 102 with the image surface facing up and a start key on an operation unit (not shown) is pressed, A document is fed to a predetermined position on a document table 105 made of contact glass by a feeding roller 103 and a feeding belt 104. The ADF 101 has a count function that counts up the number of documents every time a document is fed.

  The document on the contact glass 105 is discharged onto a sheet discharge tray 108 by a feeding belt 104 and a discharge roller 107 after image information is read by an image reading device 106 that inputs an image. When the document set detector 109 detects that the next document is on the document table 102, the lowermost document on the document table 102 is similarly contacted by the feed roller 103 and the feeding belt 104. It is fed to a predetermined position on the glass 105 and the above operation is repeated. The feeding roller 103, the feeding belt 104, and the discharging roller 107 described above are driven by a conveyance motor.

  The first paper feeding device 110, the second paper feeding device 111, and the third paper feeding device 112 that feed paper are transferred on the first tray 113, the second tray 114, and the third tray 115, respectively, when selected. A sheet of transfer paper as a material is fed, and this transfer paper is conveyed by a vertical conveyance unit 116 to a position where it abuts on a photoconductor 117 as an image carrier. Here, a photosensitive drum is used as the photosensitive member 117 and is rotated by a main motor.

  The image reading device 106 irradiates light on the original on the contact glass 105 while moving the light source 128 in the horizontal direction, and adjusts the focus of the reflected light with the lens 132 via the mirrors 129 to 131. The image data of the original is read by forming an image on the light receiving surface of the image sensor 133. In this way, the image data read from the document is converted into optical information by the writing unit 118 as writing means via an image processing means (not shown).

  The writing unit 118 performs image processing on the image data of the original read by the image reading device 106 to convert it into optical information, and scans the laser from the laser light source 134 through the lens 135 with the polygon mirror 136 while scanning the photoconductor 117. Are exposed to light.

  The surface of the photoconductor 117 is uniformly charged by a charger (not shown), and then exposed to light information from the writing unit 118 to form an electrostatic latent image. The electrostatic latent image formed on the photoreceptor 117 is developed by the developing device 119 to become a toner image.

  On the other hand, the conveyance belt 120 serves as both sheet conveyance and transfer means. A transfer bias is applied from a power source, and the transfer sheet from the vertical conveyance unit 116 is conveyed on the photoreceptor 117 while conveying the transfer sheet with the photoreceptor 117 at a constant speed. The toner image is transferred onto the transfer paper. The transfer paper is fixed with a toner image by the fixing device 121, and is discharged to the paper discharge tray 123 by the paper discharge unit 122. The fixing device 121 is a heat generating member that generates heat when it is started up, together with an AC power source, by supplying power from the rechargeable auxiliary power source of the present invention. The photoconductor 117 after the toner image is transferred is cleaned by a cleaning device (not shown) to prepare for the next image formation.

  The above-described image forming operation is an operation for copying an image on one side of a sheet in a normal mode. When copying an image on both sides of a transfer sheet in a duplex mode, each of the paper feed trays 113 to 115 is copied. The transfer paper that is fed by either of the above and having the image formed on the surface as described above is switched by the paper discharge unit 122 to the double-sided paper feed path 124 side instead of the paper discharge tray 123 side, and by the reversing unit 125. Switched back, the front and back are reversed, and conveyed to the duplex conveying unit 126. The transfer paper transported to the double-sided transport unit 126 is transported to the vertical transport unit 116 by the double-sided transport unit 126, transported to a position where it abuts on the photoconductor 117 by the vertical transport unit 116, and on the photoconductor 117 as described above. The toner image formed on the back surface is transferred to the back surface and the toner image is fixed by the fixing device 121, whereby double-sided copying is performed. This double-sided copy is discharged to the paper discharge tray 123 by the paper discharge unit 122.

  Further, when the transfer paper is reversed and discharged, the transfer paper that is switched back by the reversing unit 125 and turned upside down is not conveyed to the duplex conveying unit 126 but is discharged via the reverse discharge conveyance path 127. The paper is discharged to the paper discharge tray 123 by the unit 122.

  Further, in the print mode, image data from the outside is input to the writing unit 118 instead of the image data from the image reading device 106, and an image is formed on the transfer paper in the same manner as described above.

  In the facsimile mode, when the image data from the image reading device 106 is transmitted to the other party by a facsimile transmission / reception unit (not shown), and the image data from the other party is received by the facsimile transmission / reception unit, the image reading device 106 By inputting to the writing unit 118 instead of the image data, an image is formed on the transfer paper in the same manner as described above.

  In this embodiment, as the heat generating member of the present invention, the fixing device 121 described above is provided with a fixing heater, and the dew condensation prevention heater for preventing condensation is an optical element such as a lens or a mirror of the image reading device 106 described above. It is provided at each of a plurality of locations near the conveyance path for conveying system parts or transfer paper.

  Furthermore, a large-capacitance capacitor is used as an example of the auxiliary power source used in the present invention. FIG. 2 is a configuration diagram of an auxiliary power supply of the image forming apparatus according to the present embodiment.

  The auxiliary power source shown in FIG. 2 includes an AC power source 140, a main power switch 141, an input current detection circuit 142, a DC power source generation unit 143, a charger 144, an AC heater driving circuit 145, a control unit 146, a fixing roller 147, and a fixing heater 147a. , AC fixing heater 147b, capacitor charging / discharging circuit 148, capacitor 149, fixing thermistor 150, and the like.

  Next, the operation of this auxiliary power supply will be described. As shown in FIG. 2, the AC power source 140 includes a DC power source generation unit 143 that generates a DC power source of the image forming apparatus via a main power switch 141, a charger 144 for charging a capacitor 149, and an AC heater. An input current detection circuit 142 that detects an input current as the AC power source that is input to the drive circuit 145 is provided, and the input current value is input to the control unit 146.

  The fixing roller 147 is provided with a fixing heater 147a and an AC fixing heater 147b which are heat generating members. The AC fixing heater 147b is ON / OFF controlled by the AC heater driving circuit 145 for the AC power supply 140. The fixing heater 147a is connected to the capacitor 149 through the capacitor charging / discharging circuit 148. The capacitor 149 is a large-capacity capacitor and is charged by the charger 144. The charger 144 receives an AC power supply 140 via a main power switch 141, and an output to the capacitor 149 is turned on / off by a signal S1 from the control unit 146 of the image forming apparatus.

  Further, the electric power charged in the capacitor 149 by the charger 144 is supplied to the fixing heater 147a by the capacitor charging / discharging circuit 148. The AC power supply 140 via the main power switch 141 is also input to a DC power supply generation unit 143 that generates a DC power supply of the image forming apparatus. The DC power generation unit 143 generates a power source Vcc mainly used in the control system inside the image forming apparatus and a power source Vaa mainly used for the drive system and the medium / high voltage power source.

  Further, a fixing thermistor 150 for detecting the surface temperature of the fixing roller 147 is provided in the vicinity of the fixing roller 147, and the control unit 146 changes the resistance of the fixing roller 147 by changing the resistance value of the thermistor depending on the temperature. Detect surface temperature.

  Next, FIG. 3 is a block diagram showing a characteristic configuration of the present invention. Since the fixing heater 147a, the capacitor charging / discharging circuit 148, the capacitor 149, and the control unit 146 in FIG. 3 are the same as those in FIG.

  First, the control unit 146 and the capacitor discharge circuit 148 shown in FIG. 3 are configured to supply an auxiliary power source (hereinafter also referred to as a backup power source) such as a secondary battery when the AC power source is OFF. Referring to FIG. 2, when the AC power source 140 is turned on, the AC power source is supplied, so that the power source supplied from the charger 144 that generates the DC power source is supplied to the control unit 146 and the capacitor discharge circuit 148. When the AC power supply 140 is OFF, power is supplied from a capacitor 149 that is a backup power supply.

  The capacitor 149 is charged in advance at the time of shipment from the factory or before the service person ships to the user. The dew condensation prevention switch 151 shown in FIG. 3 is installed in a place where only the service person can access although the user cannot access.

  When the dew condensation prevention switch 151 is pressed immediately before the serviceman ships to the user, the control unit 146 detects the dew condensation prevention switch 151 being pressed and sends a discharge command to the capacitor charge / discharge circuit 148. The capacitor charging / discharging circuit 148 that has received this discharge command performs a discharging operation, whereby electric power is supplied from the capacitor 149 charged at the time of shipment from the factory to a heater as a heat generating member.

  In this embodiment, with the above-described configuration, power is supplied to a heater provided in the image forming apparatus before user shipment to perform a heating operation, thereby increasing the temperature inside the apparatus. A temperature difference with the outside occurs, and condensation can be prevented.

  In addition, as shown in FIG. 3, a normally closed AC relay 152 that opens when AC power is input is installed in a line that supplies power from the capacitor charge / discharge circuit 148 to the dew condensation prevention heaters 154 and 155. . Further, when the normally open AC relay 153 that is closed when the AC power is input is installed in a line that supplies power to the fixing heater 147a from the capacitor charging / discharging circuit 148, when the AC power is turned on, the power is supplied to the fixing heater 147a. When the AC power supply is turned off, power can be supplied to the dew condensation prevention heaters 154 and 155 installed at locations susceptible to the influence of condensation (for example, around the photoconductor, scanner unit, etc.). Prevention can be performed effectively. That is, here, the normally closed AC relay 152 and the normally open AC relay 153 constitute a switching unit.

  The control unit 146 is configured to forcibly turn off the capacitor discharge when detecting that AC power is input, and to perform normal control when the AC power is input. .

  FIG. 4 is a flowchart for explaining the operation of the capacitor charge / discharge circuit in FIG. First, it is determined whether or not the dew condensation prevention switch 151 is pressed (ON) in step S400. If not, the discharge is turned off in step S401, and the dew condensation prevention switch 151 is pressed (step S400). If ON, the discharge is turned on in step S402, and then it is determined whether or not AC power is input in step S403.

  If no AC power is input in step S403, the process returns to step S400 and the above operation is repeated. However, if there is an AC power input in step S403, the discharge is turned off in step S404.

  FIG. 5 is a flowchart for explaining a lighting operation of a warning LED for notifying that the inside of the apparatus is at a high temperature when AC power is not supplied. As shown in FIG. 5, it is determined whether or not the dew condensation prevention switch 151 has been pressed (ON) in step S500. If not, the discharge is turned off in step S501, and then the operation unit 156 shown in FIG. The warning LED 156a provided inside is also turned off (step S502). If the dew condensation prevention switch 151 is pressed (ON) in step S500, the warning LED 156a is turned on after the discharge is turned on in step S503 (step S504). Thereafter, in step S505, it is determined whether or not AC power is input.

  If no AC power is input in step S505, the process returns to step S500 and the above operation is repeated. However, if AC power is input in step S505, the discharge is turned off in step S506, and the warning LED 156a is also turned off at the same time (step S507).

  That is, a state where the AC power is not supplied and the inside of the apparatus is at a high temperature is a state that is difficult to recognize except for a service person who has turned on the dew condensation prevention switch 151. There is no denying the possibility that a user or the like may accidentally touch a high-temperature part and cause a burn. For this reason, when the power is being supplied to the dew condensation prevention heaters 154 and 155 in a state where the AC power is not turned on, the control unit 146 performs control so as to turn on the warning LED 156a installed at an easily recognizable portion of the operation unit 156. To supply power.

  As described above, when power is being supplied to the dew condensation prevention heaters 154 and 155 in a state where the AC power is not turned on, the warning LED 156a is turned on to display a warning, so that the service person or the user accidentally touches the high temperature part. The possibility can be reduced and the safety can be increased. In this embodiment, the LED is used for the notification unit. However, the present invention is not limited to this, and a warning display with characters or graphics is displayed on the operation display unit, or voice or beep sound is output via a speaker. Of course, it is also possible to configure so as to perform warning notification.

  As described above, according to the present embodiment, before visiting the user to install the product, power is supplied in advance from the chargeable capacitor to the dew condensation prevention heater, and the inside of the image forming apparatus is By warming up, it is possible to prevent the occurrence of condensation at the time of arrival and installation work, and it is possible to prevent the user from waiting and to complete the arrival work in a short time.

  In addition, according to the present embodiment, by selectively supplying power to the anti-condensation heater installed at a location effective for dew condensation, when the user visits the user for product installation, the loading and installation It is possible to efficiently prevent the occurrence of condensation during work.

  Furthermore, according to the present embodiment, when the AC power is turned off before visiting the user for product installation, power is supplied from the capacitor to the dew condensation prevention heater installed at a location effective for dew condensation. By warming the inside, it is possible to prevent the occurrence of condensation. In addition, after the AC power is turned on, the power supply destination is switched from the dew condensation prevention heater to the fixing heater, so that the startup time of the fixing heater can be shortened as an auxiliary to the main power supply, and the existing configuration is used. It can be realized at a low cost.

  Further, according to the present embodiment, when power is supplied from the capacitor to the dew condensation prevention heater in a state where AC power is not supplied to the image forming apparatus, a warning LED or the like is used for service personnel and users. By notifying them and notifying that there is a part that is partly hot, it is possible to prevent accidents such as burns.

  As described above, the image forming apparatus according to the present invention is useful for an image forming apparatus that forms an image on recording paper using an optical system component, and in particular, a copying machine, a facsimile machine, a printer, or a complex machine thereof. This is suitable for preventing the occurrence of dew condensation during the arrival and installation of the image forming apparatus.

1 is a cross-sectional view illustrating an overall configuration of an image forming apparatus used in the present invention. 1 is a configuration diagram of an auxiliary power source of an image forming apparatus according to an embodiment. It is a block diagram which shows the characteristic structure of this invention. It is a flowchart explaining operation | movement of the capacitor charging / discharging circuit in FIG. It is a flowchart explaining the lighting operation | movement of warning LED which notifies that the inside of an apparatus is high temperature in the state where AC power is not supplied.

Explanation of symbols

101 Automatic document feeder (ADF)
DESCRIPTION OF SYMBOLS 102 Document stand 103 Feed roller 104 Feed belt 105 Document stand 106 Image reading device 107 Discharge roller 108 Paper discharge stand 109 Document set detector 110 First sheet feeder 111 Second sheet feeder 112 Third sheet feeder 113 First tray 114 Second tray 115 Third tray 116 Vertical transport unit 117 Photoconductor 118 Writing unit 119 Developing device 120 Transport belt 121 Fixing device 122 Paper discharge unit 123 Paper discharge tray 124 Double-sided paper feed path 125 Reversing unit 126 Double-sided transport Unit 127 Reverse paper delivery path 128 Light source 129 to 131 Mirror 132 Lens 133 Image sensor 134 Laser light source 135 Lens 136 Polygon mirror 140 AC power supply 141 Main power switch 142 Input current detection circuit 143 DC power source Component 144 Charger 145 AC heater drive circuit 146 Controller 147 Fixing roller 147a Fixing heater 147b AC fixing heater 148 Capacitor charge / discharge circuit 149 Capacitor 150 Fixing thermistor 151 Condensation prevention switch 152 Normally closed AC relay 153 Normally open AC relay 154,155 Condensation prevention heater 156 Operation unit 156a Warning LED

Claims (4)

An image forming apparatus that forms an image on recording paper using optical system parts,
A rechargeable auxiliary power supply,
A heat generating member that generates heat by supplying power from the auxiliary power source;
With
An image forming apparatus, wherein power can be supplied from the auxiliary power source to the heat generating member even when the main power of the apparatus main body is not turned on. A plurality of the heat generating members are provided inside the apparatus main body,
The image forming apparatus according to claim 1, further comprising a switching unit capable of selectively supplying power to the plurality of heat generating members from the auxiliary power source. The plurality of heat generating members include at least one of a fixing heater used in the fixing device and a dew condensation preventing heater for preventing dew condensation inside the apparatus main body,
The image forming apparatus according to claim 2, wherein the switching unit switches a power supply destination according to a use situation.   4. The apparatus according to claim 1, further comprising a notification unit that notifies an operator that power is being supplied while power is being supplied from the auxiliary power source to the heat generating member. The image forming apparatus according to claim 1.

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