JP4476332B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an auxiliary power supply device that stores electric power supplied from a main power supply, an electric device including the auxiliary power supply, and an image forming apparatus.

  Conventionally, when supplying power to a load unit, in addition to supplying power from a commercial AC power source, a power supply device has been used to compensate for the shortage of power supply by the commercial AC power source by supplying power from an auxiliary power unit having a capacitor or the like It has been.

  For example, an image forming apparatus such as a copying machine has a fixing roller for fixing a toner image transferred onto a sheet, and power is supplied to a heating element for increasing the surface temperature of the fixing roller. As a power supply device for supplying the power, a device using the auxiliary power supply unit as described above is used for the following reasons (see, for example, Patent Document 1).

  In an image forming apparatus such as a copying machine, the surface temperature of the fixing roller is low immediately after the power is turned on or in the power saving mode, and the surface temperature of the fixing roller must be a certain temperature or higher in order to perform printing. In order to increase the surface temperature rapidly, it is necessary to increase the amount of current supplied to the heating element. However, commercial AC power supplies are regulated by the current rating of the outlet, and only currents below this rated current can be used. Therefore, in the image forming apparatus, it takes a certain amount of time to set the surface temperature of the fixing roller to a printable temperature.

  Thus, in addition to the commercial AC power supply, power is supplied to the heating unit from the capacitor serving as the auxiliary power supply unit, thereby supplying a large amount of power and reducing the time required for the surface temperature to rise.

  There has also been proposed an image forming apparatus provided with a heating element driven by a commercial AC power supply and a heating element driven by an auxiliary power supply unit charged by the AC power supply (see, for example, Patent Document 2). In such a configuration in which the heating element for the auxiliary power supply is provided, one of a charging mode in which a capacitor as an auxiliary power supply is charged from an AC power supply and a discharging mode in which power is supplied from the auxiliary power supply to the heating element is selected. I am doing so.

JP 2000-315567 A JP 2002-280146 A

  However, although the above-mentioned conventional technique is effective for the function of supplying electric power such that the fixing roller can be heated to reach the target temperature in a short time, the auxiliary power supply device can be maintained or transported. No consideration is given to safety. In other words, the above-described conventional technology does not consider leakage or electric shock that may occur when the auxiliary power supply is removed from the image forming apparatus or the like, and does not disclose measures such as countermeasures for this. .

  The present invention has been made in view of the above, and an object of the present invention is to obtain an auxiliary power supply device that can improve safety during maintenance of the auxiliary power supply, an electric device including the auxiliary power supply device, and an image forming apparatus.

In order to achieve the above object, an invention according to claim 1 is an image forming apparatus including at least an auxiliary power supply unit and a supplied unit to which electric power is supplied from the auxiliary power supply unit, the electric power supplied from a commercial power supply. A second storage unit that opens and closes a first current path that connects the power storage element provided in the auxiliary power supply unit that stores power and the commercial power source and the power storage element, and connects the power storage element and the supplied unit. Open / close means provided in the auxiliary power supply unit for opening and closing the current path, and when the auxiliary power supply unit is removed from the image forming apparatus, the first current path and the second current path are opened. And opening / closing means for performing power storage from the commercial power source to the electricity storage element, causing the opening / closing means to close the first current path, and supplying electric power from the electricity storage element to the supplied part. When supplying The second current path in serial switching means is an image forming apparatus characterized by comprising a control means for the closed state.

According to a second aspect of the present invention, there is provided an image forming apparatus including at least an auxiliary power supply unit and a supplied unit to which electric power is supplied from the auxiliary power supply unit, wherein the electric power is stored by electric power supplied from a commercial power supply. Opening / closing a power storage element provided in the auxiliary power supply unit, a first current path connecting the commercial power supply and the power storage element, and opening / closing a second current path connecting the power storage element and the supplied part Opening / closing means provided in the auxiliary power supply unit, the opening / closing means for opening the first current path and the second current path when the main power of the image forming apparatus is turned off; When the electric power supplied from the commercial power source is stored in the power storage element, the opening / closing means closes the first current path, and when power is supplied from the power storage element to the supplied part, the opening / closing is performed. Means with said second current And control means for the road closed, and an image forming apparatus comprising: a.

According to a third aspect of the present invention, in the configuration of the first or second aspect of the invention, the image forming apparatus operates with electric power supplied from the commercial power source .

According to a fourth aspect of the present invention, there is provided the charger according to any one of the first to third aspects, wherein the auxiliary power supply unit charges the power storage element with electric power supplied from the commercial power source. It is characterized by providing.

  The invention according to claim 5 is characterized in that, in the configuration of the invention according to any one of claims 1 to 4, the electric storage element is an electric double layer capacitor.

According to a sixth aspect of the present invention, in the configuration according to any one of the first to fifth aspects, the image forming apparatus includes a voltage detection unit that detects a voltage of the power storage element, and the control unit includes: When the voltage is equal to or lower than a predetermined value, the opening / closing means causes the first current path to be closed .

According to a seventh aspect of the invention, in the configuration of the sixth aspect of the invention, the image forming apparatus includes a heating element, the control means has the voltage not more than a predetermined value, and the heating element is driven. The open / close means causes the first current path to be closed when not .

The invention according to claim 8 is characterized in that, in the configuration of the invention according to any one of claims 1 to 7 , the control section is provided in the supplied section .

The invention according to claim 9 is the configuration of the invention according to any one of claims 1 to 8, wherein the opening / closing means has a first state in which the first current path is closed; The switch includes a second state in which the second current path is in a closed state and a third state in which the first current path and the second current path are in an open state .

According to a tenth aspect of the present invention, in the configuration of the first aspect of the invention, the auxiliary power supply unit detects whether the auxiliary power supply unit is attached to or detached from the image forming apparatus. And the opening / closing means opens the first current path and the second current path when the attachment / detachment state detection means detects that the auxiliary power supply is removed from the image forming apparatus. It is characterized by that .

According to the present invention, it is possible to set a shut-off state in which power cannot be transferred between the power storage element and another element, such as a charger or a load unit, by the shut-off means. Therefore, it is possible to reduce the possibility that maintenance personnel may receive an electric shock when performing maintenance or the like of the auxiliary power supply unit, and the effect of improving safety is achieved.

Further, according to the present invention, when the main power supply of the electric device is turned off, the setting unit sets the blocking unit to block the power transfer between the power storage element and the other element. Therefore, it is possible to reduce the possibility that maintenance personnel may receive an electric shock when performing maintenance or the like of the auxiliary power supply unit after turning off the main power supply, and the effect of improving safety is achieved.

Further, according to the present invention, when the auxiliary power supply is removed from the main body of the electric device for maintenance, transportation, etc., the cutoff means is configured to transfer power between the power storage element and another element by the setting means. Is set to shut off. Therefore, after removing the auxiliary power supply unit, it is possible to reduce a possibility that the maintenance staff may receive an electric shock when performing maintenance or the like of the auxiliary power supply unit, and the safety is improved.

In addition, according to the present invention, by using an electric double layer capacitor as a power storage element, quick charge is possible, life is long, and high power discharge is possible compared to the case of using a nickel cadmium battery or the like. In addition, there is an effect that safety is improved.

  Exemplary embodiments of an auxiliary power supply apparatus, an electric apparatus, and an image forming apparatus according to the present invention will be explained below in detail with reference to the accompanying drawings.

A. First Embodiment FIG. 1 is a diagram showing an appearance of a copying machine 1 provided with an auxiliary power supply apparatus according to a first embodiment of the present invention. As shown in FIG. 1, a copying machine 1 includes a main body 10 that performs a copying operation, a large-capacity paper feeding unit 11 that accommodates a large amount of paper and supplies it to the main body 10, and paper on which copying has been performed. A finisher 12 for sorting, punching, binding, and the like is provided for the sheets, and the paper on which copying, sorting, and the like have been performed is discharged to the paper discharge unit 17.

  The main body 10 has an automatic document feeder 13 disposed on the upper part thereof, and a document set on the automatic document feeder 13 is scanned by a scanner unit 101 described later by the automatic document feeder 13. It is conveyed so that it may pass.

  In addition, an operation unit 14 in which an interface such as a display panel for displaying various information to the user and buttons for allowing the user to input various instructions and the like is provided on the upper portion of the main body unit 10. The operation unit 14 includes a main power switch (see FIG. 3) for turning on / off the main power of the copying machine 1, and the user turns on the copying machine 1 by turning on the main power switch. The power supply to the copying machine 1 can be turned off and the operation can be stopped by turning off the main power switch.

  In addition, a paper feeding unit 15 is provided below the main body unit 10, and image formation is performed on an image forming target sheet such as a sheet or an OHP sheet stored in the paper feeding unit 15. Become.

  As shown in FIG. 2, the main unit 10 includes a scanner unit 101, a writing unit 102, a photosensitive unit 103, a charging unit 104, a developing unit 105, a transfer unit 106, a paper feeding unit 108, and a fixing unit. A unit 111.

  The scanner unit 101 is disposed on the upper side of the copying machine, irradiates light on a document placed on a platen glass (not shown) installed above, and photoelectrically converts the reflected light. Scan the original image. The automatic document feeder 13 also reads a document image that is passed over the platen glass.

  The writing unit 102 projects a laser beam corresponding to the document image read by the scanner unit 101 onto each photosensitive drum of the photosensitive unit 103.

  The photoconductor unit 103 includes photoconductor drums corresponding to four colors such as C (cyan), M (magenta), Y (yellow), and Bk (black). The charging unit 104 is disposed around the photosensitive drum and charges the photosensitive drum. The developing unit 105 forms a toner image by attaching toner onto the photosensitive drum on which the latent image is formed by the writing unit 102.

  The transfer unit 106 has a transfer belt that conveys the paper along the horizontal direction of the drawing, which is the arrangement direction of the photosensitive drums corresponding to the colors, and the transfer belt writes the paper to the transfer position by the photosensitive drum. It arrives. As a result, the image of that color is transferred to the paper at the transfer position of each photosensitive drum.

  The paper feed unit 15 includes a plurality of paper feed trays, and feeds a predetermined size of paper from the paper feed tray onto the transfer belt during copying. As a result, the fed paper is conveyed to the transfer position by the transfer unit 106 as described above, and the image is transferred onto the paper.

  The fixing unit 111 is a unit that heats and pressurizes the sheet on which the image has been transferred as described above to fix the transferred toner onto the sheet, and includes a fixing roller 112 and a pressure roller 113. A plurality of heating elements are arranged in the hollow portion of the cylindrical fixing roller 112, and the heating elements generate heat by supplying electric power to these heating elements from a power supply device to be described later. The surface temperature of 112 increases. The heating element may be disposed in the hollow portion of the fixing roller, but may be disposed in another position as long as the heating element can be heated. For example, the heating element is disposed in the hollow portion of the pressure roller 113. May be equal.

  In this way, the sheet on which the toner image is transferred is passed between the fixing roller 112 and the pressure roller 113 whose surface temperature is equal to or higher than a certain temperature, so that the sheet is heated and pressurized. ing.

  Next, a circuit configuration of a power supply device that supplies electric power to the heating element disposed in the fixing roller 112 will be described with reference to FIG. As shown in the figure, the power supply device includes an auxiliary power supply device 210, heating elements 201, 202, 203, an auxiliary heating element 204, and a control unit 211.

  Electric power is supplied from the commercial AC power supply 208 to the auxiliary power supply device 210 and the three heating elements 201, 202, and 203. The auxiliary heating element 204 is not directly supplied with electric power from the commercial AC power supply 208 but is supplied with electric power from the auxiliary power supply 210 charged by electric power from the commercial AC power supply 208.

  In the present embodiment, as described above, the heating elements 201, 202, and 203 that generate heat upon receiving power supply from the commercial AC power supply 208 and the auxiliary heating element 204 that generates heat upon receiving power supply from the auxiliary power supply 210 are fixed. The fixing roller 112 is heated by the heat generated in the hollow portion of the roller 112.

  A temperature detection unit 212 for detecting the temperature of the fixing roller 112 heated by the heating elements 201, 202, 203 and the auxiliary heating element 204 is provided, and the detection result by the temperature detection unit 212 is supplied to the control unit 211. The

  Also, switches 221, 222, and 223 for switching on / off the power supply to these heating elements 201, 202, and 203 are provided, and the on / off of these switches 221, 222, and 223 is controlled by the control unit. 211 is controlled.

  The control unit 211 includes a CPU (Central Processing Unit) and the like, and switches 221, 222, and 223 are turned on / off so that the temperature of the fixing roller 112 detected by the temperature detection unit 212 becomes a preset temperature. To control. In addition, the control unit 211 performs control to switch the switch states of the switch 225 and the switch 226 in the auxiliary power device 210. The details of such switching control will be described later.

  The auxiliary power supply device 210 includes a switch 226, a charger 231, a remaining voltage detection circuit 232, a switch 225, and an electric double layer capacitor 233.

  The switch 226 is a switch that switches on / off the power supply from the commercial AC power supply 208 to the auxiliary power supply device 210, and is turned on / off under the control of the control unit 211. The switch 225 has three states: a state connected to the charger 231 side (left side in FIG. 3), a state connected to the auxiliary heating element 204 side (right side in FIG. 3), and a state not connected to any of them. The switch 225 is set to one of the states under the control of the control unit 211.

  The charger 231 charges the electric double layer capacitor 233 with power supplied from the commercial AC power source 208. When the switch 226 is on and the switch 225 is connected to the charger 231 side, the electric double layer capacitor 233 is charged by the charger 231.

  The remaining voltage detection circuit 232 detects the charging voltage value of the electric double layer capacitor 233 and outputs the detected voltage value to the control unit 211. The control unit 211 controls the state of the switch 225 based on the charging voltage value of the electric double layer capacitor 233 detected by the residual voltage detection circuit 232 and determines whether or not the electric double layer capacitor 233 is charged. Control.

  In the present embodiment, an electric double layer capacitor 233 is used as the storage element of the auxiliary power supply device 210. As a power storage element of the auxiliary power supply 210, a secondary battery such as a nickel cadmium battery can be used, but in the present embodiment, attention is paid to the following excellent characteristics of the electric double layer capacitor not involving a chemical reaction, An electric double layer capacitor 233 is used as the storage element.

(1) The charging time is short In an auxiliary power source using a nickel-cadmium battery, which is a general secondary battery, several hours are required even if rapid charging is performed. On the other hand, an auxiliary power source using a capacitor can be rapidly charged for several minutes. Because of this characteristic, charging and discharging can be performed frequently, so that the number of times of heating using the auxiliary power source can be increased when compared within the same time.

(2) Long life The nickel-cadmium battery has a short life as an auxiliary power source for heating because the number of charge / discharge cycles is 500 to 1000, and there is a problem in labor and cost of replacement. On the other hand, an auxiliary power source using a capacitor has a long life and does not have a memory effect, so that deterioration due to repeated charging and discharging is small. Therefore, it is particularly advantageous for a heating apparatus or an image forming apparatus that repeats a non-heating operation (during standby) and a heating operation. Also, unlike lead-acid batteries, there is no need for liquid replacement or replenishment, so little maintenance is required.

(3) Large power can be discharged for a short time Secondary batteries cannot discharge the stored power at a stretch, so the heating unit cannot supply large power when starting from low temperature, and it is low for shortening the start-up time Only the effect can be expected. On the other hand, an auxiliary power source using a capacitor can discharge a large amount of power in a few seconds, and is effective in shortening the startup time.

(4) High safety even if the battery continues to be charged Since the secondary battery uses a chemical reaction, if it is not necessary to discharge after charging to its maximum capacity, the chemical reaction will continue if it is connected to the charging circuit. There is a risk that the container may expand and burst due to gas generated by On the other hand, since the auxiliary power source using the capacitor uses a physical phenomenon rather than a chemical reaction, there is no generation of gas and it is safe to continue charging.

  The electric double layer capacitor 233 has excellent characteristics as described above, and in recent years, a product capable of storing a large amount of electric energy has been developed. For example, an electric double layer capacitor developed by Nippon Chemi-Con Co., Ltd. has a capacitance of about 2000 F, and has a sufficient capacity for supplying power for several seconds to several tens of seconds. A capacitor of about 80 F is also sold by NEC Corporation under the trade name Hypercapacitor. As the electric double layer capacitor 233 in this embodiment, an electric double layer capacitor capable of storing a large amount of electric energy can be used.

  The above is the configuration of the power supply device according to the present embodiment. Hereinafter, the operation of driving the heating elements 201 to 204 and the charging of the auxiliary power supply device 210 by the power supply device performed based on the control of the control unit 211 will be described.

  First, as shown in FIG. 4, when the main power switch 250 (see FIG. 3) of the copying machine 1 is turned on, the control unit 211 controls the temperature of the fixing roller 112 and the like supplied from the temperature detection unit 212. Obtain (step Sa1). Then, the controller 211 subtracts the detected temperature from the preset target temperature (step Sa2), and obtains a temperature difference between the target temperature and the current temperature.

  When the temperature difference from the target temperature is obtained as described above, the control unit 211 compares the temperature difference with a preset threshold value and determines whether or not the temperature difference is greater than the preset threshold value. Is determined (step Sa3).

  Here, when the temperature difference between the target temperature and the current temperature is larger than a preset threshold value (determination “Yes” in step Sa3), the control unit 211 turns on the switches 221, 222, and 223. Then, the heating elements 201, 202, and 203 are driven to heat the fixing roller 112 and the like. In addition, the control unit 211 controls the switch 225 to be connected to the auxiliary heating element 204 side (the right side in FIG. 3), thereby causing the electric double layer capacitor 233 to supply power to the auxiliary heating element 204, that is, The multilayer capacitor 233 is discharged to drive the auxiliary heating element 204 (step Sa4).

  When the heating by the four heating elements 201 to 204 is performed, the control unit 211 determines whether or not the temperature of the fixing roller 112 or the like detected by the temperature detection unit 212 has reached the target temperature (step Sa5). .

  When the target temperature has not been reached, the control unit 211 continues to supply power from the commercial AC power supply 208 to the three heating elements 201 to 203 and supplies power from the auxiliary power supply device 210 to the auxiliary heating element 204. The four heating elements are driven by continuing (step Sa4). And the control part 211 performs the heating which driven the four heat generating bodies 201-204 until the temperature detected by the temperature detection part 212 reaches | attains target temperature (step Sa4-step Sa5).

  On the other hand, when the temperature detected by the temperature detection unit 212 reaches the target temperature by driving the four heating elements 201 to 204 (determination “Yes” in step Sa5), the process proceeds to standby processing (step Sa6). .

  In the determination of step Sa3, when the temperature difference between the target temperature and the current temperature is smaller than a preset threshold value (determination “No”), the processing of steps Sa4 to Sa5, that is, Control is not performed to drive the four heating elements 201 to 204 until the target temperature is reached, and the process proceeds to a standby process (step Sa6).

  In the standby process by the control unit 211, the three heating elements 201 to 203 are driven by turning on the switches 221, 222, and 223 so that the temperature detected by the temperature detection unit 212 becomes the target temperature. At this time, the switch 225 is not connected to the auxiliary heating element 204 side (the right side in FIG. 3), and as a result, power supply from the electric double layer capacitor 233 to the auxiliary heating element 204 is not performed.

  In the standby processing by the control unit 211, the charging voltage value of the electric double layer capacitor 233 supplied from the remaining voltage detection circuit 232 is compared with a preset threshold value, and is equal to or less than the threshold value, and 3 When the two heating elements 201 to 203 are not driven, the electric double layer capacitor 233 is charged.

  That is, when the charging voltage value of the electric double layer capacitor 233 is equal to or lower than the threshold value and the switches 221, 222, and 223 are off, the control unit 211 turns on the switch 226 and charges the switch 225. It is set as the state connected to the container 231 side (left side of FIG. 3). As a result, the electric double layer capacitor 233 is charged with the electric power from the commercial AC power supply 208.

  On the other hand, when the voltage value detected by the residual voltage detection circuit 232 exceeds the threshold value or the heating elements 201 to 203 are driven, the control unit 211 stops charging the electric double layer capacitor 233.

  As described above, when the target temperature and the current temperature have a large difference after the main power is turned on (when the temperature difference from the target temperature is larger than the threshold value), the control unit 211 can be executed in a shorter time. The auxiliary heating element 204 is heated in addition to the three heating elements 201 to 203 so that the fixing unit reaches the target temperature.

  For example, if the target temperature is 180 ° C. and the detected temperature is 28 ° C., the temperature difference is as large as 152 ° C. (for example, the threshold is set to 30 ° C.), and four heat generations The body is driven to reach the target temperature of 180 ° C. in a short time.

  On the other hand, when the difference between the target temperature and the current temperature is not so large (when the temperature difference is smaller than the threshold value), the auxiliary heating element 204 is not used and heating by the three heating elements 201 to 203 is performed. Is called. In the case of the above example, when the detected temperature is 150 ° C. or higher, the temperature difference is less than 30 ° C., so that the temperature can be increased to 180 ° C. in a sufficiently short time with only the three heating elements 201 to 203. Therefore, in such a case, the auxiliary heating element 204 is not driven.

  In addition to not using the auxiliary heating element 204 as described above, the electric double layer capacitor 233 that supplies power to the auxiliary heating element 204 is charged while the auxiliary heating element 204 is not used. That is, the electric double layer capacitor 233 is charged at a timing when the auxiliary heating element 204 need not be used to drive the auxiliary heating element 204 thereafter.

  Further, this charging is performed when charging such that the charging voltage of the electric double layer capacitor 233 is low and when the three heating elements 201 to 203 are not driven. That is, it is performed at a timing that requires charging and at a timing that does not hinder driving of the heating elements 201 to 203 by the power of the commercial AC power supply 208.

  The operation described above is performed after the main power switch 250 of the copier 1 is turned on. In this embodiment, after the main power switch 250 is turned off, the control unit 211 performs the following power supply device. Control is to be performed.

  That is, as shown in FIG. 5, the control unit 211 constantly monitors whether or not the main power switch 250 is switched off while the power of the copier 1 is on (step Sb1). When the switch 250 is turned off, power supply to a load other than the auxiliary power supply device 210, for example, a load such as the heating elements 201 to 203 is cut off (step Sb2). That is, power supply to other loads is shut off by turning off the switches 221, 222, and 223, for example.

  Next, the control unit 211 sets the switch 225 in the auxiliary power device 210 to a state where it is not connected to either the charger 231 side or the auxiliary heating element 204 side, and the electric double layer capacitor 233 in the auxiliary power device 210 is connected. It is set as the interruption | blocking state which is not connected with the other elements for the purpose of transmission / reception of electric power for charge and discharge, such as the auxiliary heat generating body 204 and the charger 231 (step Sb3). That is, in the present embodiment, the switch 225 functions as a blocking unit that blocks power transfer between the electric double layer capacitor, which is a power storage element, and other elements, and is the control unit 211 set to a blocking state by the blocking unit? It functions as a setting means for setting whether to enter the non-blocking state.

  Then, it is confirmed whether or not the switch 225 is turned off and the electric double layer capacitor 233 is disconnected from other elements such as the charger 231 and the auxiliary heating element 204 (step Sb4), and no confirmation is made. In that case, the process returns to step Sa3 to control the switch 225 to be turned off. On the other hand, when it is confirmed that the switch 225 is turned off, the control unit 211 turns off the power of the copying machine 1 (step Sb5).

  In the present embodiment, when the main power switch 250 is turned off, the main power supply is not turned off as it is, but the electric double layer capacitor 233 that is a power storage element in the auxiliary power supply device 210, the electric double layer capacitor 233, The power source is turned off after the elements (charger 231 and auxiliary heating element 204) connected for charging and discharging are shut off.

  Therefore, it is possible to prevent the power stored in the electric double layer capacitor 233, which is a power storage element, from leaking to other elements as described above while the main power is turned off, Even when the power is turned off, it is possible to suppress the amount of power storage from being greatly reduced.

  Further, even when a maintenance person or the like performs work on the auxiliary power supply device 210 for maintenance or the like, power transfer between the electric double layer capacitor 233 and other elements is interrupted. Therefore, an electric shock or the like can be prevented and work safety is improved.

  Further, in this embodiment, when the main power switch 250 of the copying machine 1 that is a device on which the power supply device is mounted is turned off, the control unit 211 automatically responds to the electric double layer capacitor 233 and other elements. Therefore, the user can obtain the effects of maintaining the stored energy and improving the safety without performing a separate instruction or operation to perform such power interruption.

B. Second Embodiment Next, a copying machine provided with an auxiliary power supply apparatus according to a second embodiment of the present invention will be described. The copier in the second embodiment has the same configuration as the copier 1 in the first embodiment, and the configuration of the power supply apparatus is different from that of the first embodiment. In the following, differences between such power supply apparatuses will be described with reference to FIG. In the second embodiment, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof is omitted.

  As shown in the figure, the power supply device according to the second embodiment includes the configuration of the power supply device according to the first embodiment (see FIG. 3), the point of having a cutoff setting unit 301 in the auxiliary power supply device, and the auxiliary power supply device It is different in that it is detachable.

  That is, the auxiliary power supply device 310 of the power supply device in the second embodiment includes switches 225 and 226, a charger 231, an electric double layer capacitor 233, and a residual voltage detection circuit 232 as well as the first embodiment, and is configured to be cut off. Part 301 is provided.

  Further, the auxiliary power supply device 310 according to the second embodiment is configured such that the above-described elements such as the charger 231 and the electric double layer capacitor 233 are arranged in one casing unit, and the casing unit is disposed in the copying machine. As shown in FIG. 6, each circuit element of the auxiliary power supply 310 is connected to the commercial AC power supply 208 and the auxiliary heating element 204, which are elements outside the auxiliary power supply 310, as shown in FIG. 6. It has become so.

  In the state where the auxiliary power supply device 310 is mounted, the switch states of the switches 225 and 226 under the control of the control unit 211 are appropriately set as in the first embodiment, and the electric double layer is formed at a predetermined timing. The capacitor 233 is charged, and power is supplied from the electric double layer capacitor 233 to the auxiliary heating element 204 at a predetermined timing.

  When the auxiliary power supply 310, which is detachable as described above, is removed from the state where it is attached to the power supply apparatus, the cutoff setting unit 301 switches the switch 225 to either the charger 231 side or the auxiliary heating element 204 side. In other words, the electric double layer capacitor 233 in the auxiliary power supply device 310 is in a disconnected state in which it is not connected to other elements such as the charger 231 for the purpose of transferring power for charging.

  More specifically, the cutoff setting unit 301 includes an attachment / detachment state detection unit 302 that detects whether the auxiliary power supply device 310 is in an attached state or a removed state. When the detection result is removed, the switch 225 is controlled to be turned off.

  As shown in FIG. 7, the attachment / detachment state detection unit 302 according to the present embodiment includes an on / off switch 303 and a displacement member 304 that is movable between a position where the switch 303 is turned on and a position where the switch 303 is turned off. ing. Then, the displacement member 304 moves to a position where the on / off switch 303 is turned on by a mechanical configuration when the auxiliary power supply 310 is attached, and retracts to a position where it turns off when the auxiliary power supply device 310 is removed. It is supposed to be.

  Under such a configuration, when the on / off switch 303 is switched off, the cutoff setting unit 301 turns off the switch 225. Thus, when the auxiliary power supply 310 is removed, the switch 225 is turned off. It is done.

  In the second embodiment, when the auxiliary power supply 310 that is detachable as described above is removed, the switch 225 is automatically turned off, that is, the electric double layer capacitor that is a power storage element in the auxiliary power supply 210. 233 and the electric double layer capacitor 233 and the charger 231 which is an element connected for charging are cut off.

  Therefore, as in the first embodiment, the power stored in the electric double layer capacitor 233 can be prevented from leaking to other elements as described above, and the power can be turned off for a long time. Also, it is possible to suppress a significant decrease in the amount of stored electricity. In addition, when performing maintenance on the removed auxiliary power supply device 310 or transporting the auxiliary power supply device 310, since electric power transfer between the electric double layer capacitor 233 and other elements is interrupted, it is possible to prevent electric shock and the like. Work safety is improved.

  In the present embodiment, the auxiliary power supply device 310 that is made detachable is simply removed, and the electric double layer capacitor 233 and the other elements are automatically cut off accordingly. The effect of maintaining the stored energy and improving the safety can be obtained without performing a separate instruction or operation in order to cut off the power.

C. Modifications The present invention is not limited to the first and second embodiments described above, and various modifications as exemplified below are possible.

(Modification 1)
In the first embodiment described above, when the main power switch 250 is turned off, the switch 225 in the auxiliary power device 210 is turned off, so that the electric double layer capacitor 233 is connected to other elements such as the charger 231. Although the power is cut off, the storage element (capacitor or the like) in the auxiliary power supply device 210 and the means (switch or the like) that can cut off the storage element and other elements connected for charging or discharging. So that when the main power switch 250 is turned off, it is cut off by the means.

  For example, as shown in FIG. 8, a main power switch 250 is provided separately from a switch 225 for switching between a charging state (connected to the left side of FIG. 3) and a discharging state (connected to the right side of FIG. 3) in the first embodiment. Switches 701 and 702 for shutting off the electric double layer capacitor 233, the charger 231 and the auxiliary heating element 204 when the switch is turned off may be provided.

(Modification 2)
In the second embodiment described above, it is detected that the auxiliary power supply device 310 has been removed by the attachment / detachment state detection unit 302 having the on / off switch 303 and the displacement member 304 that turns on / off the switch according to the attachment / detachment state. In this case, the switch 225 is turned off, but in this case as well, the blocking means other than the switch 225 is provided and the blocking means is operated when it is detected that the switch 225 is removed. Thus, the electric double layer capacitor 233 and other elements may be cut off.

  Further, the means for detecting the attachment / detachment state is not limited to the configuration as in the second embodiment, but from the state where the auxiliary power supply device 310 is attached to the main body 801 as schematically shown in FIG. If the auxiliary power supply device 310 is removed, a shut-off means 802 (for example, a switch) that automatically shuts off the transfer of power between the electric double layer capacitor 233 and other elements according to the removal is provided. Good.

  For example, as shown in FIG. 10, on / off switches 801 and 802 for cutting off the electric double layer capacitor 233, the charger 231 and the auxiliary heating element 204 are not provided, but a switch for detecting the attachment / detachment state is provided. Provide. Then, when such an on / off switch 801, 802 is directly or indirectly engaged with a member on the main body side in a state where the auxiliary power supply device 310 is mounted, both the switches 801, 802 are turned on. Displacement members 803 and 804 are provided that retreat to positions where the engagement is released and the on / off switches 801 and 802 are turned off when the auxiliary power supply 310 is removed. In this way, the electric double layer capacitor 233 and other elements are automatically shut off when the auxiliary power supply device 310 is removed without providing means such as a dedicated switch for detecting the attachment / detachment state. be able to.

  In addition, it is not limited to a configuration in which the switch position is changed by a member that is displaced depending on whether or not the auxiliary power supply device 310 is mounted, and the presence or absence of the mounted state is detected using a photo sensor or a magnetic sensor. A configuration may be adopted in which the electric double layer capacitor 233 is disconnected from other elements in accordance with the presence / absence of the mounted state thus detected. For example, you may make it provide the photo sensor which provided the light emitting element and light receiving element which are arrange | positioned oppositely, and the shielding member provided so that it could advance / retreat according to the presence or absence of a mounting state between these elements. Further, a magnetic sensor is provided in the vicinity of the magnetic member provided on the main body side in a state where the auxiliary power supply 310 is mounted, and it is determined whether or not the auxiliary power supply 310 is in a mounted state from the detection result of the magnetic sensor. You may make it do.

(Modification 3)
In the first and second embodiments described above, the case where the present invention is applied to the copying machine 1 having the fixing unit 111 has been described. However, power is supplied to an image forming apparatus other than the copying machine or some load unit. The present invention can be applied to an electric device provided with an auxiliary power supply to be supplied.

1 is a diagram illustrating an appearance of a copying machine according to an embodiment of the present invention. It is a figure which shows the structure of the main-body part of the said copying machine. FIG. 2 is a diagram illustrating a circuit configuration of a power supply device of the copying machine. 3 is a flowchart showing control contents for a power supply apparatus performed by a control unit after the copying machine is turned on. 3 is a flowchart showing control contents for a power supply device performed by a control unit after a main power supply of the copying machine is turned off. It is a figure which shows the circuit structure of the power supply device used for the copying machine concerning 2nd Embodiment of this invention. It is a figure which shows the typical structure of the attachment / detachment state detection part 302 which is a component of the power supply device in 2nd Embodiment. It is a figure which shows the modification of the power supply device in 1st Embodiment. It is a figure which shows schematic structure of the modification of the power supply device in 2nd Embodiment. It is a figure which shows the modification of the power supply device in 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Copier 10 Main body part 11 Large capacity paper feed part 12 Finisher 13 Automatic document feeder 14 Operation part 15 Paper feed part 17 Paper discharge part 101 Scanner part 102 Writing part 103 Photosensitive unit 104 Charging part 105 Development part 106 Transfer part 108 Paper feeding unit 111 Fixing unit 112 Fixing roller 113 Pressure roller 201, 202, 203 Heating element 204 Auxiliary heating element 208 Commercial AC power supply 210 Auxiliary power supply 211 Control unit 212 Temperature detection unit 221, 222, 223, 225, 226 Switch 231 Charger 232 Residual voltage detection circuit 233 Electric double layer capacitor 250 Main power switch 301 Cutoff setting unit 302 Attachment / detachment state detection unit 303 Switch 304 Displacement member 310 Auxiliary power supply device 701, 702 Switch 801, 802 Off switch

Claims (10)

  An image forming apparatus comprising at least an auxiliary power supply unit and a supplied unit to which power is supplied from the auxiliary power supply unit,
  A storage element provided in the auxiliary power supply unit that is stored by electric power supplied from a commercial power supply;
  Opening / closing means provided in the auxiliary power supply unit for opening / closing a first current path connecting the commercial power source and the power storage element and opening / closing a second current path connecting the power storage element and the supplied part An opening / closing means for opening the first current path and the second current path when the auxiliary power source is removed from the image forming apparatus;
  When the electric power supplied from the commercial power source is stored in the power storage element, the opening / closing means closes the first current path, and when power is supplied from the power storage element to the supplied part, the opening / closing is performed. Control means for causing the means to close the second current path;
  An image forming apparatus comprising:   An image forming apparatus comprising at least an auxiliary power supply unit and a supplied unit to which power is supplied from the auxiliary power supply unit,
  A storage element provided in the auxiliary power supply unit that is stored by electric power supplied from a commercial power supply;
  Opening / closing means provided in the auxiliary power supply unit for opening / closing a first current path connecting the commercial power source and the power storage element and opening / closing a second current path connecting the power storage element and the supplied part Open / close means for opening the first current path and the second current path when the main power supply of the image forming apparatus is turned off;
  When the electric power supplied from the commercial power source is stored in the power storage element, the opening / closing means closes the first current path, and when power is supplied from the power storage element to the supplied part, the opening / closing is performed. Control means for causing the means to close the second current path;
  An image forming apparatus comprising:   The image forming apparatus according to claim 1, wherein the image forming apparatus operates with electric power supplied from the commercial power source.   4. The image forming apparatus according to claim 1, wherein the auxiliary power unit includes a charger that charges the power storage element with electric power supplied from the commercial power source. 5.   The image forming apparatus according to claim 1, wherein the storage element is an electric double layer capacitor.   The image forming apparatus includes a voltage detection unit that detects a voltage of the storage element,
  6. The image forming apparatus according to claim 1, wherein the control unit causes the opening / closing unit to close the first current path when the voltage is equal to or lower than a predetermined value. .   The image forming apparatus includes a heating element,
  7. The control unit according to claim 6, wherein the control unit causes the opening / closing unit to close the first current path when the voltage is equal to or lower than a predetermined value and the heating element is not driven. Image forming apparatus.   The image forming apparatus according to claim 1, wherein the control unit is provided in the supplied unit.   The opening / closing means includes a first state in which the first current path is closed, a second state in which the second current path is closed, and the first current path and the second current. The image forming apparatus according to claim 1, wherein the image forming apparatus is a switch having a third state in which the path is opened.   The auxiliary power supply unit includes attachment / detachment state detection means for detecting whether the auxiliary power supply unit is attached to or removed from the image forming apparatus,
  When the attachment / detachment state detection unit detects that the auxiliary power supply unit is removed from the image forming apparatus, the opening / closing unit opens the first current path and the second current path. The image forming apparatus according to claim 1.

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