Charging device, charging method, and image forming apparatus

Abstract

To make it possible to grasp a cause when abnormality occurs in a charging device.SOLUTION: A charging device 101 includes: a DC power supply 10 for supplying a load current that is a DC current to a DC load 103; a secondary battery 102; a charging control unit 111 that is electrically connected to the DC power supply 10, the DC load 103, and the secondary battery 102 to control charging of the secondary battery 102; and an abnormal section determination unit 122 for determining an abnormal section based on input information on an output voltage A of the DC power supply 10, an input current B of the charging n unit 111, an input voltage C of the DC load 103, a charging current D of the secondary battery 102, and a discharge current E.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a charging device, a charging method, and an image forming apparatus. [Background technology]

[0002] 2. Description of the Related Art A charging device is known that charges a secondary battery using surplus power, other than the power supplied to a load, from a power source with a limited power supply.

[0003] Patent Document 1 discloses a configuration for charging a secondary battery by making maximum use of the power supply capacity by varying the charging current according to the load, in order to make maximum use of the power supply capacity and shorten the charging time of the secondary battery. Summary of the Invention [Problem to be solved by the invention]

[0004] However, if some kind of abnormality occurs in the charging device, it may not be possible to identify the cause (identify the abnormal part, including a loose connector), and non-faulty modules may also be replaced at the same time.

[0005] An object of the present invention is to make it possible to grasp the cause of an abnormality that occurs in a charging device. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, a charging device according to one aspect of the present invention includes a DC power supply that supplies a load current, which is a DC current, to a DC load; a secondary battery; a charging control unit that is electrically connected to the DC power supply, the DC load, and the secondary battery and controls charging of the secondary battery; a charger within the charging control unit that uses the DC power supply as an input and supplies a charging current to the secondary battery; a current detection unit that detects a current that is the sum of the load current and the charging current of the DC power supply; a charging current control unit that variably charges and controls the charging current so that the current detected by the current detection unit is within the allowable power of the DC power supply; a remaining capacity detection unit that detects and integrates the charging current and discharging current of the secondary battery to determine the remaining capacity of the secondary battery; and an abnormality location determination unit that determines the location of an abnormality based on input information of the output voltage of the DC power supply, the input current of the charging control unit, the input voltage of the DC load, and the charging and discharging current of the secondary battery. [Effects of the Invention]

[0007] If an abnormality occurs in the charging device, the cause can be identified. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram illustrating an example of the configuration of an image forming apparatus according to an embodiment. [Figure 2] Power supply configuration diagram inside image forming device [Figure 3] A diagram illustrating the basic operation of a conventional charging device. [Figure 4] Functional block diagram of a charging device according to a first embodiment [Figure 5] FIG. 10 is a diagram showing an example of an abnormality location determination table. [Figure 6] Diagram explaining the operation when the abnormality is in the DC power supply [Figure 7] Diagram explaining operation when the abnormality is in the charger [Figure 8] A diagram explaining the operation when the abnormality is due to the first connector coming loose [Figure 9] A diagram explaining the operation when the abnormality is due to the second connector coming loose [Figure 10]A diagram explaining the operation when the abnormality is caused by the third connector coming loose. [Figure 11] A diagram explaining the operation when the abnormality is in the secondary battery [Figure 12] Diagram explaining operation when the abnormality is in a DC load [Figure 13] Flowchart of abnormality location determination process [Figure 14] Functional block diagram of a charging device according to a second embodiment [Figure 15] Functional block diagram of a charging device according to a third embodiment DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments will be described with reference to the accompanying drawings. To facilitate understanding of the description, the same components in the drawings will be denoted by the same reference numerals as much as possible, and duplicated descriptions will be omitted.

[0010] [First embodiment] The first embodiment will be described with reference to FIGS.

[0011] <Configuration of image forming device> First, the configuration of an image forming apparatus 100 to which a charging device 101 according to this embodiment is applied will be described with reference to Figures 1 and 2. Figure 1 is a diagram illustrating an example of the configuration of the image forming apparatus 100 according to this embodiment. Figure 1 is a side view in which the interior of the image forming apparatus 100 is partially seen through.

[0012] Image forming device 100 is a multifunction peripheral (MFP) that combines functions such as copying, faxing, printing, and scanning, as well as the ability to store and distribute input images (documents scanned by the scanner function, and images input by the printer or fax function).

[0013] Image forming apparatus 100 can also communicate with external devices such as PCs (Personal Computers) and can perform operations in accordance with instructions received from the external devices. In this embodiment, the "image" processed by image forming apparatus 100 includes not only image data but also data that does not contain image data, i.e., data that contains only text information.

[0014] The image forming apparatus 100 is a so-called electrophotographic image forming apparatus that adheres toner to an electrostatic latent image written by selectively exposing a charged photosensitive surface, and transfers the adhered toner to a recording medium such as paper.

[0015] As shown in FIG. 1, the image forming apparatus 100 has an operation panel 1, a start switch 2, a controller 3 that controls the image forming apparatus 100 based on operation inputs from the operation panel 1, a reading unit 4 that reads a document, an engine control unit 5 that generates a control signal based on the reading result of the reading unit 4, a printer unit 6 as an image forming unit that forms an image on a recording medium such as paper, paper feed cassettes 7A and 7B that store the recording medium, and a transport unit 8 as a paper feed transport unit.

[0016] The operation panel 1, which is an operation unit, accepts various inputs in response to user operations and displays various information (e.g., information indicating the accepted operations, information indicating the operating status of the image forming apparatus 100, information indicating the setting status of the image forming apparatus 100, etc.). The operation panel 1 is configured, for example, by a liquid crystal display (LCD) equipped with a touch panel function, but is not limited to this. For example, the operation panel 1 may be configured by an organic electroluminescence (EL) display equipped with a touch panel function. Furthermore, in addition to or instead of this, an operation unit such as hardware keys and a display unit such as a lamp may also be provided.

[0017] When the user presses the start switch 2 while the power of the image forming apparatus 100 is off, the start switch 2 starts the image forming apparatus 100. When the user presses the start switch 2 while the image forming apparatus 100 is started, that is, while the power is on, the start switch 2 turns the image forming apparatus 100 off. In this way, the start switch 2 may turn the image forming apparatus 100 on / off by being pressed by the user, but this is not limiting, and the image forming apparatus 100 may also be turned on / off based on an instruction received from an external device.

[0018] The controller 3 comprehensively controls the image forming apparatus 100. As one example, the controller 3 causes the image forming apparatus 100 to perform an operation in accordance with an operation or information received by the operation panel 1. As another example, the controller 3 causes the image forming apparatus 100 to perform an instruction received by the image forming apparatus 100 from an external device such as a PC (Personal Computer). As yet another example, the controller 3 causes the image forming apparatus 100 to perform a predetermined operation when a specific condition is detected, for example, when the controller 3 detects that the start switch 2 has been pressed, or as yet another example, when the controller 3 detects that an abnormality has occurred in the image forming apparatus 100.

[0019] A specific example of the controller 3 is a controller board equipped with a circuit that comprehensively controls the image forming apparatus 100. This circuit includes, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RA (Read Only Memory). The image forming apparatus 100 is controlled by a CPU that uses RAM as a work area and executes programs stored in ROM or HDD (Hard Disc Drive).

[0020] The reading unit 4 has an ADF (Auto Document Feeder) 41 and a scanner unit 42. The ADF 41 sequentially transports documents placed on the ADF 41, optically reads them, and generates image data. The scanner unit 42 fixes documents on a transparent document platen, optically reads the fixed documents, and generates image data.

[0021] The engine control unit 5 generates control signals for controlling the printer unit 6 and the transport unit 8 based on the image data generated by the reading unit 4. A specific example of the engine control unit 5 is a circuit board for generating control signals based on image data.

[0022] The printer unit 6, which is the image forming section, has a photosensitive drum 61 as a photosensitive member, a charging member 62 that charges the outer surface of the photosensitive drum 61, a writing unit 63 that exposes the charged photosensitive drum 61 based on image data read by the reading section 4 and writes an electrostatic latent image on the photosensitive member, a developing member 64 that develops the written latent image with toner, a conveying belt 65 that conveys the recording medium on which the toner image is formed, and a fixing section 66 that fixes the toner on the recording medium to the recording medium, thereby forming a toner image on the recording medium.

[0023] Paper feed cassettes 7A and 7B store recording media before image formation. In Fig. 1, two paper feed cassettes are shown as an example, each storing recording media of a different size, but the number of cassettes may be one or three or more.

[0024] A transport unit 8 as a paper feed transport section has various rollers and transports recording media stored in paper feed cassettes 7A and 7B to printer unit 6.

[0025] Here, the flow of image formation in image forming apparatus 100 will be described using copy mode as an example. First, a user operates a function switching key or the like on operation panel 1 to sequentially select and operate the copy function, printer function, and facsimile function of image forming apparatus 100. When the copy function is selected, the apparatus enters copy mode, when the printer function is selected, the apparatus enters printer mode, and when the facsimile function is selected, the apparatus enters facsimile mode.

[0026] In the copy mode, the reading unit 4 reads image information from each document to be copied, and generates image data.

[0027] The outer peripheral surface of the photosensitive drum 61 is uniformly charged in the dark by the charging member 62, and then exposed to light (shown by the dotted arrow A in FIG. 1) from the writing unit 63. , an electrostatic latent image is formed on the outer peripheral surface of the photosensitive drum 61. The developing member 64 visualizes this electrostatic latent image with toner. As a result, a toner image is formed on the photosensitive drum 61. The toner image formed on the photosensitive drum 61 is transferred to a recording medium on a conveyor belt 65. Then, a fixing unit 66 heats and melts the toner of the toner image on the recording medium, for example, using a heater, to fix the toner image to the recording medium, and the recording medium is discharged from the image forming apparatus 100.

[0028] Although the printer unit 6 has been described as forming images by a monochrome electrophotographic method, the image forming method is not limited to these and may be a color electrophotographic method or an inkjet method.

[0029] Furthermore, the above-described operation panel 1 may be controlled by the controller 3, or may have a control circuit 7 for controlling the operation panel 1 separate from the controller 3 and be controlled by the control circuit 7. In this case, the control circuit of the controller 3 and the control circuit of the operation panel 1 are connected to each other so that they can communicate with each other, and the controller 3 controls the entire image forming apparatus 100 including the operation panel 1.

[0030] Although the controller 3, engine control unit 5, printer unit 6, paper feed cassettes 7A and 7B, and transport unit 8 are provided inside the exterior of the image forming apparatus 100, FIG. 1 shows the interior in a see-through manner.

[0031] 2 is a diagram showing the power supply configuration within the image forming apparatus 100. The image forming apparatus 100 is shown connected to a commercial power source.

[0032] The image forming apparatus 100 includes an AC (Alternating Current) control unit 9 and a DC power supply 10. The image forming apparatus 100 further includes a charging device 101 and a secondary battery .

[0033] The AC control unit 9 supplies AC voltage input from a commercial power source to the fixing unit 66. The engine control unit 5 controls the ON / OFF of the fixing heater of the fixing unit 66, to which AC voltage is supplied by the engine control unit 5.

[0034] The DC power supply 10 is connected to a charging device 101 and is a power supply system that supplies power to the controller 3 and the secondary battery 102 via the charging device 101. The DC power supply 10 is connected to the controller 3 and the secondary battery 102 via the charging device 101.

[0035] The DC power supply 10 is connected to a charging device 101 and is a power supply system that supplies power to DC loads such as the reading unit 4, the image forming unit 6, and the transport unit 8 via the charging device 101 and the engine control unit 5. The DC power supply 10 is connected to the engine control unit 5 via the charging device 101, and is further connected from the engine control unit 5 to DC loads such as the reading unit 4, the image forming unit 6, and the transport unit 8. Hereinafter, the DC loads such as the reading unit 4, the image forming unit 6, and the transport unit 8 may be collectively referred to as a "DC load 103." The controller 3 may also be included as part of the DC load 103.

[0036] The charging device 101 controls the power supply from the DC power supply 10 to the controller 3 and the DC load 103, and the charging of the secondary battery 102 from the DC power supply 10. Therefore, the charging device 101 also functions as a power supply device for the controller 3 and the DC load 103.

[0037] The operation of image forming apparatus 100 with the power supply configuration shown in Fig. 2 will be described. When power is normally supplied to image forming apparatus 100 from an external power source such as a commercial power source, power from DC power supply 10 is supplied to controller 3. Here, the amount of power required varies depending on the operation of controller 3, so surplus power that is not used for the operation of controller 3 is supplied to secondary battery 102, and secondary battery 102 is charged with this surplus power.

[0038] When a power outage occurs due to a disaster or the like, that is, when the power supply from the external power source that is normally supplied is stopped, power is supplied from the secondary battery 102 to the DC power supply 10 of the image forming apparatus 100. In other words, the secondary battery 102 functions as an auxiliary power supply for the DC power supply 10.

[0039] Here, by providing the controller 3 with the functions of controlling the operation panel 1 and the facsimile, the controller 3 can operate even during a power outage, receive facsimile data, and store it in an HDD (Hard Disc Drive) or the like of the image forming apparatus 100. Then, when power starts to be supplied by a UPS (Uninterruptible Power Supply) capable of supplying AC power, or when the power is restored from the power outage, the stored facsimile data can be printed out.

[0040] <Reference form> The configuration of a conventional charging device 101C in an image forming apparatus 100 equipped with a DC power supply 10 will be described with reference to Fig. 3. The configuration and basic operation (charging / discharging) will be described. Fig. 3 is a functional block diagram of a conventional charging device 101C according to a reference embodiment, and is a diagram illustrating the basic operation of the charging device 101C. Fig. 3(A) shows the operation during charging, and Fig. 3(B) shows the operation during discharging.

[0041] As shown in FIG. 3(A), during charging, the charging device 101C supplies power from the DC power supply 10 to the load 103 (the arrow labeled "load current" in the figure) while charging the secondary battery 102 with surplus power from the DC power supply 103 (the arrow labeled "charging current" in the figure).

[0042] As shown in FIG. 3(B), during discharging, the charging device 101C supplies power from the secondary battery 102 to the load 103 (arrow of "discharge current" in the figure).

[0043] 3, the charging device 101C includes a charging control unit 111. The charging control unit 111 is electrically connected to the DC power supply 10, the DC load 103, and the secondary battery 102, and controls the charging of the secondary battery 102. The charging control unit 111 also controls operations such as the supply of power from the DC power supply 10 to the DC load 103 and the controller 3, the charging of the secondary battery 102 by the DC power supply 10, and the discharging of the secondary battery 102 to the DC load 103.

[0044] The charging control unit 111 is electrically connected to the DC power supply 10 via connectors 116 and 117 (first connectors), electrically connected to the DC load 103 via connectors 118 and 119 (second connectors), and electrically connected to the secondary battery 102 via connectors 120 and 121 (third connectors).

[0045] The charging control unit 111 includes a charger 112 , a current detection unit 113 , a charging current control unit 114 , and a remaining amount detection unit 115 .

[0046] The charger 112 receives the DC power supply 10 as input and supplies a charging current to the secondary battery 102. The charger 112 is connected to the current detection unit 113 and the charging current control unit 114 on the upstream side of the current direction, and to the remaining charge detection unit 115 on the downstream side. In this embodiment, the current direction refers to the direction in which current flows from the DC power supply 10 to the DC load 103 and the secondary battery 102 via the charging control unit 111, and the DC power supply 10 side of this current direction is called the upstream side, and the DC load 103 side is called the downstream side.

[0047] The current detection unit 113 detects a current (output current of the DC power supply 10) which is the sum of the load current and the charging current of the DC power supply 10 (current detection step). The current detection unit 113 is connected to the DC power supply 10 on the upstream side in the current direction, and is connected to the DC load 103, the charging current control unit 114, and the charger 112 on the downstream side.

[0048] The charging current control unit 114 performs variable charging control of the charging current so that the current detected by the current detection unit 113 is within the allowable power of the DC power supply 10 (charging current control step). In other words, the charging current to the secondary battery 102 varies depending on the DC load 103. The maximum supplyable current of the DC power supply 10, set by the charging current control unit 114, varies depending on the operating state of the image forming apparatus 100 notified from, for example, the controller 3. When the image forming apparatus 100 is in a silent mode (energy saving, standby), the allowable power is small, and when in a normal mode (copying, etc.), the cooling fan is also rotating and the maximum supplyable current is large. The charging current control unit 114 is connected to the current detection unit 113 on the upstream side of the current direction and to the charger 112 on the downstream side.

[0049] The remaining capacity detection unit 115 detects and integrates the charging current and discharging current of the secondary battery 102 to determine the remaining capacity of the secondary battery 102 (remaining capacity detection step). The remaining capacity detection unit 115 is connected to the charger 112 on the upstream side of the current direction and to the secondary battery 102 on the downstream side.

[0050] <Configuration of main parts of the first embodiment> The essential configuration of the first embodiment will be described with reference to FIGS.

[0051] The configuration of the first embodiment will be described with reference to Fig. 4. Fig. 4 is a functional block diagram of a charging device 101 according to the first embodiment. Only the additional changes from the embodiment shown in Fig. 3 will be described.

[0052] The charging device 101 includes an abnormality location determination unit 122. The charging control unit 111 includes a switch 123 (mode switching unit).

[0053] The abnormality part determination unit 122 monitors whether or not an abnormality has occurred in the charging device 101, and if any abnormality occurs, determines the abnormality part. The abnormality part determination unit 122 acquires the output voltage A of the DC power supply 10, the input current B of the charging control unit 111, the input voltage C of the DC load 103, the charging current D and the discharging current E of the secondary battery 102 as input information, and performs the above monitoring and determination.

[0054] The input current B of the charge control unit 111 is obtained by acquiring the current value between the current detection unit 113 and the charge current control unit 114, for example, as shown in Fig. 4. The charge current D and discharge current E of the secondary battery 102 are obtained by acquiring information on the charge current and discharge current held by the remaining charge detection unit 115 for detecting the remaining charge, for example, as shown in Fig. 4. The abnormality point determination unit 122 may also acquire the operating state of the controller 3 as input information.

[0055] Based on the above input information, the abnormality location determination unit 122 determines the abnormality location as follows: a failure of the DC power supply 10, a failure of the charger 112, a disconnection of the first connector (connector 116 or connector 117 connecting the DC power supply 10 and the charging control unit 111), a disconnection of the second connector (connector 118 or connector 119 connecting the charging control unit 111 and the DC load 103), a disconnection of the third connector (connector 120 or connector 121 connecting the charging control unit 111 and the secondary battery 102), a failure of the secondary battery 102, or a failure of the DC load 103.

[0056] The abnormal part determining unit 122 may be configured to determine at least some of the above-mentioned abnormal part candidates.

[0057] The abnormal part determination unit 122 also has an abnormal part determination table in which the combinations of patterns of the detection results of the above-mentioned input information and the correspondence relationships between multiple abnormal part candidates are recorded. The abnormal part determination unit 122 can identify an abnormal part from the multiple abnormal part candidates by referring to the abnormal part determination table based on the input information.

[0058] Fig. 5 is a diagram showing an example of an abnormality location determination table. In the example of Fig. 5, the input information includes five types of combinations of detection locations and detection information: the output voltage A of the DC power supply 10, the input current B of the charging control unit 111, the input voltage C of the DC load 103, the charging current D of the secondary battery 102, and the discharging current E. Furthermore, depending on the combination pattern of whether or not the input information can be detected, eight types of detection results are included: "No abnormality," "Fault of the DC power supply 10," "Fault of the charger 112," "Disconnection of the first connector," "Disconnection of the second connector," "Disconnection of the third connector," "Fault of the secondary battery 102," and "Fault of the DC load 103." In the table of Fig. 5, cases where each piece of input information can be detected are indicated by "◯," and cases where it cannot be detected are indicated by "X."

[0059] 5 based on input information, the abnormal part determination unit 122 may be configured not to use the abnormal part determination table. For example, the abnormal part determination unit 122 may have a predictor that outputs information that identifies the abnormal part when the above-mentioned input information is input, and the input / output relationship of the predictor may be obtained in advance by a machine learning technique, and the abnormal part may be determined using the trained predictor.

[0060] The switch 123 is disposed between the current detection unit 113 and the DC load 103 and upstream of the charger 112. The switch 123 switches between an on state and an off state, thereby switching between supplying and cutting off the output current of the DC power supply 10 to the DC load 103 and the charger 112 downstream in the current direction.

[0061] When the switch 123 is in the on state, the system is in a charge mode in which the charging current of the DC power supply 10 is supplied to the secondary battery 102 via the charger 112. On the other hand, when the switch 123 is in the off state, the charging current of the DC power supply 10 is not supplied to the secondary battery 102, and the load current of the DC power supply 10 is not supplied to the DC load 103, so the system is in a discharge mode in which the discharge current from the secondary battery 102 is supplied to the DC load 103 via the charge control unit 111. In other words, the switch 123 functions as a mode switching unit that switches the secondary battery 102 between the charge mode and the discharge mode.

[0062] The switch 123 is connected to the abnormal part determination unit 122 and operates in response to a command from the abnormal part determination unit 122. In the abnormal part determination process, the abnormal part determination unit 122 switches the switch 123 between an on state and an off state. The timing of switching the switch 123 by the abnormal part determination unit 122 will be described later with reference to FIG. 13 .

[0063] The switch 123 may be any element that has the function of switching whether to supply or cut off the output current of the DC power supply 10 to the DC load 103 and the charger 112 downstream in the current direction, and may be configured to apply an element other than a switch that has a similar function.

[0064] An overview of the operation of the abnormal point determination unit 122 is as follows, for example. When any device in the DC load 103 abnormally stops, a determination start signal is sent from the controller 3 to the abnormal point determination unit 122. In response to receiving this signal, the abnormal point determination unit 122 detects the voltage values ​​and current values ​​at the points (A to E) shown in Fig. 5. Based on each detected value, the abnormal point determination unit 122 refers to the abnormal point determination table in Fig. 5 and determines which pattern in the determination table the combination of detection results corresponds to.

[0065] If there is no abnormality, the operation will be as shown in Figure 3, for example, and information can be detected from all detection points (A to E). In this case, the combination of detection results will be "normal" and it will be determined that there is no abnormality. On the other hand, if there is some abnormality, there will be points among the detection points (A to E) where values ​​cannot be detected. For example, if no detection is possible at A, B, and D, the combination of detection results will be "Pattern 1," and it can be determined that the cause of the abnormality is "fault in the DC power supply 10." Note that if the combination of detection results does not correspond to the patterns in the abnormality point determination table shown in Figure 5, it will be determined that there is an abnormality in another point.

[0066] When the discharge current E is detected, the abnormal point determination unit 122 turns off the switch 123 to cut off the power supply from the DC power supply 10 and forcibly switches to a discharging operation. As a result, the operation mode of the charging device 101 is forcibly switched to a discharging mode.

[0067] Next, each abnormality pattern will be described individually with reference to FIGS.

[0068] Fig. 6 is a diagram for explaining the operation when the abnormal part is DC power supply 10. Fig. 6(A) is a diagram showing the operation of charging device 101 when switch 123 is in the on state, and Fig. 6(B) is a diagram showing the operation of charging device 101 when switch 123 is in the on state. The same applies to the following Figs. 7 to 12.

[0069] As shown in FIG. 6, when the DC power supply 10 is faulty, the output voltage A of the DC power supply 10 is undetectable (×) because the DC power supply 10 is not operating and does not output any voltage. Furthermore, the input current B of the charging control unit 111 is undetectable (×) because the DC power supply 10 is not operating and power is not supplied to the charging control unit 111. The input voltage C of the DC load 103 is detectable (◯) because the DC power supply 10 is not operating and power is supplied to the load 103 from the secondary battery 102. The charging current D at the connection point between the charging control unit 111 and the secondary battery 102 is undetectable (×) because power is not supplied from the DC power supply 10 to the charging control unit 111 and the charger 112 is not operating. The discharging current E at the connection point between the charging control unit 111 and the secondary battery 102 is detectable (◯) because power is supplied from the secondary battery 102 to the DC load 103. The detection patterns of these signals A to E are the same whether the switch 123 shown in FIG. 6(A) is in the on state or the switch 123 shown in FIG. 6(B) is in the off state.

[0070] Therefore, when the DC power supply 10 is faulty, the combination of input information A to E acquired by the abnormality part determination unit 122 corresponds to "Pattern 1" in the abnormality part determination table of FIG. 5, and therefore the abnormality part determination unit 122 can determine that "DC power supply is faulty."

[0071] When the DC power supply 10 is faulty, the DC power supply 10 does not operate and does not output voltage, so that the system enters a discharge mode in which a discharge current is supplied from the secondary battery 102 to the DC load 103, whether the switch 123 shown in FIG. 6(A) is in the on state or the switch 123 shown in FIG. 6(B) is in the off state.

[0072] FIG. 7 is a diagram illustrating the operation when the abnormality is in the charger 112. As shown in FIG. 7, when the charger 112 is faulty, the output voltage A of the DC power supply 10 is detectable (◯) because the DC power supply 10 operates and outputs a voltage. Furthermore, the input current B of the charging control unit 111 is detectable (◯) because power is supplied from the DC power supply 10 to the charging control unit 111. The input voltage C of the DC load 103 is detectable (◯) because power is supplied from the DC power supply 10 to the DC load 103. The charging current D at the connection point between the charging control unit 111 and the secondary battery 102 is undetectable (×) because the charger 112 is not operating. The discharging current E at the connection point between the charging control unit 111 and the secondary battery 102 is detectable (◯) because power is supplied from the secondary battery 102 to the DC load 103. The detection patterns of these signals A to E are the same whether the switch 123 shown in FIG. 7(A) is in the on state or the switch 123 shown in FIG. 7(B) is in the off state.

[0073] Therefore, if the charger 112 is faulty, the combination of input information A to E acquired by the abnormality part determination unit 122 corresponds to "Pattern 2" in the abnormality part determination table of Figure 5, and the abnormality part determination unit 122 can determine that the charger is faulty.

[0074] 7(A) is in the ON state, a load current is supplied from the DC power supply 10 to the DC load 103, but no charging current is supplied from the charger 112 to the secondary battery 102. On the other hand, when the switch 123 shown in FIG. 7(B) is in the OFF state, a discharging mode is entered in which a discharging current is supplied from the secondary battery 102 to the DC load 103.

[0075] 8 is a diagram illustrating the operation when the abnormality is due to the first connector being disconnected. As shown in FIG. 8, when the first connector (connector 116 or connector 117) is disconnected, the output voltage A of the DC power supply 10 is detectable (◯) because the DC power supply 10 operates and outputs a voltage. Furthermore, the input current B of the charging control unit 111 is undetectable (×) because the DC power supply 10 and the charging control unit 111 are not connected and no power is supplied to the charging control unit 111. The input voltage C of the DC load 103 is undetectable (×) because the DC power supply 10 and the charging control unit 111 are not connected and no power is supplied to the DC load 103. The charging current D at the connection point between the charging control unit 111 and the secondary battery 102 is undetectable (×) because the DC power supply 10 and the charging control unit 111 are not connected and the charger 112 is not operating. Discharge current E at the connection point between charge control unit 111 and secondary battery 102 is detectable (◯) because power is supplied from secondary battery 102 to DC load 103. The detection patterns of these signals A to E are the same whether switch 123 shown in Fig. 8(A) is in the on state or switch 123 shown in Fig. 8(B) is in the off state.

[0076] Therefore, when the first connector is unplugged, the combination of input information A to E acquired by the abnormality part determination unit 122 corresponds to "Pattern 3" in the abnormality part determination table of Figure 5, and therefore the abnormality part determination unit 122 can determine that "the first connector is unplugged."

[0077] When the first connector is unplugged, power is not supplied from the DC power source 10 to the charging control unit 111, so that the discharge mode is entered in which a discharge current is supplied from the secondary battery 102 to the DC load 103, whether the switch 123 shown in FIG. 8(A) is in the on state or the switch 123 shown in FIG. 8(B) is in the off state.

[0078] 9 is a diagram illustrating the operation when the abnormality is due to the second connector being disconnected. As shown in FIG. 9, when the second connector (connector 118 or connector 119) is disconnected, the output voltage A of the DC power supply 10 is detectable (◯) because the DC power supply 10 operates and outputs a voltage. Furthermore, the input current B of the charging control unit 111 is detectable (◯) because power is supplied from the DC power supply 10 to the charging control unit 111. The input voltage C of the DC load 103 is undetectable (×) because the charging control unit 111 and the DC load 103 are not connected and power is not supplied to the DC load 103. The charging current D at the connection between the charging control unit 111 and the secondary battery 102 is detectable (◯) because power is supplied from the DC power supply 10 to the charging control unit 111 and the charger 112 operates. The discharge current E at the connection point between the charge control unit 111 and the secondary battery 102 is undetectable (×) because the charge control unit 111 is not connected to the DC load 103 and power is not supplied to the DC load 103. The detection patterns of these signals A to E are the same whether the switch 123 shown in Fig. 9(A) is in the on state or the switch 123 shown in Fig. 9(B) is in the off state.

[0079] Therefore, when the second connector is unplugged, the combination of input information A to E acquired by the abnormality part determination unit 122 corresponds to "Pattern 4" in the abnormality part determination table of Figure 5, and therefore the abnormality part determination unit 122 can determine that "the second connector is unplugged."

[0080] 9(A) is in the on state, the charging control unit 111 and the DC load 103 are not connected, so no load current is supplied to the DC load 103, and a charging current is supplied from the charger 112 to the secondary battery 102, resulting in a charging mode. On the other hand, when the switch 123 shown in FIG. 9(B) is in the off state, no load current is supplied from the DC power supply 10 to the DC load 103, and no charging current is supplied from the DC power supply 10 to the charger 112, so the secondary battery 102 is neither charged nor discharged.

[0081] Fig. 10 is a diagram illustrating the operation when the abnormality is caused by the third connector being disconnected. As shown in Fig. 10, when the third connector (connector 120 or connector 121) is disconnected, the output voltage A of the DC power supply 10 is detectable (◯) because the DC power supply 10 operates and outputs a voltage. Furthermore, the input current B of the charging control unit 111 is detectable (◯) because power is supplied from the DC power supply 10 to the charging control unit 111. The input voltage C of the DC load 103 is detectable (◯) because power is supplied from the DC power supply 10 to the DC load 103. The charging current D at the connection between the charging control unit 111 and the secondary battery 102 is undetectable (X) because the charging control unit 111 and the secondary battery 102 are not connected and power is not supplied to the secondary battery 102. The discharge current E at the connection point between the charge control unit 111 and the secondary battery 102 is undetectable (×) because the charge control unit 111 and the secondary battery 102 are not connected and power is not supplied from the secondary battery 102 to the DC load 103. The detection patterns of these signals A to E are the same whether the switch 123 shown in Fig. 10(A) is in the on state or the switch 123 shown in Fig. 10(B) is in the off state.

[0082] Therefore, when the third connector is unplugged, the combination of input information A to E acquired by the abnormal part determination unit 122 corresponds to "Pattern 5-1" in the abnormal part determination table of Figure 5, and therefore the abnormal part determination unit 122 can determine that "the third connector is unplugged."

[0083] When the third connector is disconnected, if the switch 123 shown in Fig. 10(A) is in the on state, a load current is supplied from the DC power supply 10 to the DC load 103, but the charge control unit 111 and the secondary battery 102 are not connected, so no charging current is supplied from the charger 112 to the secondary battery 102. On the other hand, if the switch 123 shown in Fig. 10(B) is in the off state, no load current is supplied from the DC power supply 10 to the DC load 103, and also, the charge control unit 111 and the secondary battery 102 are not connected, so no charging current is supplied from the charger 112 to the secondary battery 102. Therefore, the secondary battery 102 is neither charged nor discharged.

[0084] FIG. 11 is a diagram illustrating the operation when the abnormality is in the secondary battery 102. As shown in FIG. 11, when the secondary battery 102 is faulty, the output voltage A of the DC power supply 10 is detectable (◯) because the DC power supply 10 operates and outputs a voltage. Furthermore, the input current B of the charging control unit 111 is detectable (◯) because power is supplied from the DC power supply 10 to the charging control unit 111. The input voltage C of the DC load 103 is detectable (◯) because power is supplied from the DC power supply 10 to the DC load 103. The charging current D at the connection point between the charging control unit 111 and the secondary battery 102 is undetectable (×) because the secondary battery 102 cannot be charged. The discharging current E at the connection point between the charging control unit 111 and the secondary battery 102 is undetectable (×) because power cannot be supplied from the secondary battery 102 to the DC load 103. The detection patterns of these signals A to E are the same whether the switch 123 shown in FIG. 11(A) is in the on state or the switch 123 shown in FIG. 11(B) is in the off state.

[0085] Therefore, if the secondary battery 102 is faulty, the combination of input information A to E acquired by the abnormality part determination unit 122 corresponds to "Pattern 5-2" in the abnormality part determination table of Figure 5, and the abnormality part determination unit 122 can determine that the secondary battery is faulty.

[0086] 11 and 10, the detection result pattern is the same when the secondary battery 102 is faulty and when the third connector is unplugged, but the worker can first check whether the third connector is unplugged, and if it is not the cause, identify that the cause is a fault in the secondary battery 102. Because the configuration of the charging device 101 means that the third connector (connectors 120 and 121) and the secondary battery 102 are located close to each other, the above determination also has the effect of reducing work time.

[0087] When the secondary battery 102 is faulty, if the switch 123 shown in Fig. 11(A) is in the on state, a load current is supplied from the DC power supply 10 to the DC load 103, but a charging current cannot be supplied from the charger 112 to the secondary battery 102. On the other hand, if the switch 123 shown in Fig. 11(B) is in the off state, a load current is not supplied from the DC power supply 10 to the DC load 103, and a charging current cannot be supplied from the charger 112 to the secondary battery 102. Therefore, the secondary battery 102 is neither charged nor discharged.

[0088] Fig. 12 is a diagram illustrating the operation when the abnormality location is the DC load 103. As shown in Fig. 12, when the DC load 103 is faulty, the output voltage A of the DC power supply 10 is detectable (◯) because the DC power supply 10 operates and outputs a voltage. Furthermore, the input current B of the charging control unit 111 is detectable (◯) because power is supplied from the DC power supply 10 to the charging control unit 111. The input voltage C of the DC load 103 is detectable (◯) because power is supplied from the DC power supply 10 to the DC load 103. In this case, the input voltage C is supplied to a location other than the faulty location within the DC load 103.

[0089] The charging current D at the connection point between the charging control unit 111 and the secondary battery 102 is detectable (◯) because power is supplied from the DC power supply 10 to the charging control unit 111, causing the charger 112 to operate. The discharging current E at the connection point between the charging control unit 111 and the secondary battery 102 is detectable (◯) because power is supplied from the secondary battery 102 to the DC load 103. Note that in this case, the discharging current E is supplied to a location other than the fault within the DC load 103. The detection patterns of these signals A to E are the same whether the switch 123 shown in FIG. 12(A) is in the on state or the switch 123 shown in FIG. 12(B) is in the off state.

[0090] Therefore, when the DC load 103 is faulty, the combination of input information A to E acquired by the abnormality part determination unit 122 corresponds to "Pattern 6" in the abnormality part determination table of FIG. 5, and therefore the abnormality part determination unit 122 can determine that the DC load 103 is faulty.

[0091] In addition, in pattern 6, all of the input information can be detected (◯), which is the same pattern as in normal times. However, the abnormality point determination unit 122 can distinguish between normal times and normal times because the controller 3 on the device side of the DC load 103 performs determination processing after detecting an abnormality.

[0092] 12(A) is in the ON state, a charge mode is entered in which a load current is supplied from the DC power supply 10 to a part other than the faulty part in the DC load 103, and a charge current is supplied from the charger 112 to the secondary battery 102. On the other hand, when the switch 123 shown in FIG. 12(B) is in the OFF state, a discharge mode is entered in which a discharge current is supplied from the secondary battery 102 to a part other than the faulty part in the DC load 103.

[0093] 13 is a flowchart of the abnormal part determination process. Each step in the flowchart of FIG.

[0094] When the charging device 101 is in a normal state, each device of the DC load 103 operates normally (NO in step S01), and so the charging device 101 waits until an abnormality occurs. On the other hand, when an abnormality occurs in the charging device 101, one of the devices of the DC load 103 abnormally stops (YES in S01), and so a signal instructing the abnormality part determination unit 122 to start determination is sent from the controller 3 to the abnormality part determination unit 122 (step S02).

[0095] In response to receiving this signal, the abnormality part determination unit 122 can detect the occurrence of an abnormality, and proceeds to step S03 to start the abnormality part determination process (abnormality part determination step).

[0096] First, switch 123 is switched to the ON state (step S03), power is supplied from DC power supply 10 to charging control unit 111, and normally, a charging mode is performed for secondary battery 102. In this state, output voltage A of DC power supply 10, input current B of charging control unit 111, input voltage C of DC load 103, and charging current D of secondary battery 102 are detected (steps S04 to S07).

[0097] Next, the switch 123 is switched to the OFF state (step S08), so that no power is supplied from the DC power source 10 to the charge control unit 111, and the secondary battery 102 is in the discharge mode under normal circumstances. In this state, the discharge current E of the secondary battery 102 is detected (step S09). Thereafter, the switch 123 is returned to the ON state (step S10). That is, the abnormality portion determination unit 122 forcibly switches the secondary battery 102 to the discharge mode using the switch 123, and acquires the discharge current E of the secondary battery 102 as input information.

[0098] Next, based on the combination pattern of the detection results (detected (◯) or not (×)) of each signal A to E detected in steps S04 to S07 and S09, the abnormality location is identified by referring to the abnormality location determination table in Figure 5.

[0099] If the detection results of the signals A to E correspond to pattern 1 in the abnormality location determination table (YES in step S11), the cause of the abnormality is determined to be "fault in the DC power supply 10" (step S12), and this control flow ends.

[0100] If the detection results of each signal A to E do not correspond to pattern 1 in the abnormality location determination table (NO in step S11) but correspond to pattern 2 (YES in step S13), it is determined that the cause of the abnormality is a "fault in charger 112" (step S14), and this control flow is terminated.

[0101] If the detection results of each signal A to E do not correspond to pattern 2 in the abnormality location determination table (NO in step S13) but correspond to pattern 3 (YES in step S15), the cause of the abnormality is determined to be "disconnection of the first connector" (step S16), and this control flow is terminated.

[0102] If the detection results of each signal A to E do not correspond to pattern 3 in the abnormality location determination table (NO in step S15) but correspond to pattern 4 (YES in step S17), the cause of the abnormality is determined to be "disconnection of the second connector" (step S18), and this control flow is terminated.

[0103] If the detection results of each signal A to E do not correspond to pattern 4 in the abnormality location determination table (NO in step S17) but correspond to pattern 5-1 (YES in step S19), it is determined that the cause of the abnormality is "disconnection of the third connector" (step S20), and this control flow is terminated.

[0104] If the detection results of each signal A to E do not correspond to pattern 5-1 in the abnormality location determination table (NO in step S19) but correspond to pattern 5-2 (YES in step S21), it is determined that the cause of the abnormality is a "failure of the secondary battery 102" (step S22), and this control flow is terminated.

[0105] If the detection results of each signal A to E do not correspond to pattern 5-2 in the abnormality location determination table (NO in step S21) but correspond to pattern 6 (YES in step S23), it is determined that the cause of the abnormality is a "fault in the DC load 103" (step S24), and this control flow is terminated.

[0106] If the detection results of each signal A to E do not correspond to pattern 6 in the abnormality location determination table (NO in step S23), the abnormality location is not identified, or an abnormality is determined to be in a location other than the candidate abnormality location registered in the determination table, and this control flow is terminated.

[0107] In this way, in the charging device 101 of the first embodiment, the abnormality location determination unit 122 can determine the location of an abnormality based on input information of the output voltage A of the DC power supply 10, the input current B of the charging control unit 111, the input voltage C of the DC load 103, the charging current D of the secondary battery 102, and the discharging current E. With this configuration, the cause of the abnormality can be identified by aggregating and analyzing various types of information in the charging device 101, so that when an abnormality occurs in the charging device, the cause can be easily grasped.

[0108] Conventionally, when some kind of abnormality occurs in charging device 101, it is not possible to isolate the cause, and in order to investigate the cause in the field, a process such as disassembling the device is required, resulting in a problem of long downtime at the delivery destination of the charging device. In contrast, charging device 101 of this embodiment makes it possible to easily isolate the cause of the abnormality without disassembling the device by analyzing the various input information described above, thereby reducing downtime at the delivery destination of the charging device when an abnormality occurs in the charging device.

[0109] Furthermore, in the past, if the cause of a failure was unknown, non-faulty modules were also replaced at the same time as service repairs, resulting in unnecessary parts consumption and an increase in parts purchasing costs. In contrast, the charging device 101 of this embodiment can easily isolate the cause of the abnormality by analyzing the various input information described above, thereby reducing unnecessary consumption of service-owned parts.

[0110] Furthermore, in the charging device 101 of the first embodiment, the abnormality point determination unit 122 has an abnormality point determination table in which combinations of patterns of detection results of input information A to E and correspondence relationships between multiple abnormality point candidates are recorded, and identifies an abnormality point from the multiple abnormality point candidates by referring to the abnormality point determination table based on the input information. With this configuration, it is possible to easily and quickly identify an abnormality point based on the input information simply by referring to the abnormality point determination table in which input / output relationships are associated in advance.

[0111] [Second embodiment] The second embodiment will be described with reference to Fig. 14. Fig. 14 is a functional block diagram of a charging device 101A according to the second embodiment.

[0112] 14, the charging device 101A of the second embodiment includes a notification unit 124 that notifies an abnormal part based on the result of determination by the abnormal part determination unit 122. The notification unit 124 can notify a service person of the charging device 101A of information on the abnormal part identified by the abnormal part determination unit 122 using, for example, text information or audio information, and urge the person to repair it.

[0113] In this way, the charging device 101A of the second embodiment is provided with the notification unit 124, and thus it is possible to notify the service center of the abnormality location quickly and clearly, thereby further shortening the repair time.

[0114] [Third embodiment] The third embodiment will be described with reference to Fig. 15. Fig. 15 is a functional block diagram of a charging device 101B according to the third embodiment.

[0115] 14, the charging device 101B of the third embodiment differs from the charging device 101 of the first embodiment in that it does not include a current detection unit 113 and a charging current control unit 114. That is, the charging device 101B of the third embodiment is configured such that the charging control unit 111A does not vary the charging current.

[0116] Even in the configuration of the third embodiment, the abnormality location determination unit 122A can identify the abnormality location by using the input voltage B' of the charger 112 as the detection location instead of the input current B of the charging control unit 111A as input information. That is, the abnormality location determination unit 122A determines the abnormality location based on input information of the output voltage A of the DC power supply 10, the input voltage B' of the charger 112, the input voltage C of the DC load 103, the charging current D of the secondary battery 102, and the discharging current E of the secondary battery 102.

[0117] In this way, even in a charging device that does not have the function of varying the charging current according to the DC load 103, such as the charging device 101B of the third embodiment, it is possible to determine the abnormality with high accuracy, as in the first embodiment.

[0118] The present embodiment has been described above with reference to specific examples. However, the present disclosure is not limited to these specific examples. Design modifications to these specific examples made by a person skilled in the art as appropriate are also included within the scope of the present disclosure as long as they comprise the features of the present disclosure. The elements of the above-described specific examples, as well as their arrangement, conditions, shape, etc., are not limited to those exemplified and can be modified as appropriate. The elements of the above-described specific examples can be combined in various ways as appropriate, as long as no technical contradictions arise. [Explanation of symbols]

[0119] 10 DC power supply 100 Image forming device 101, 101A, 101B charging device 102 Secondary battery 103 DC load 111, 111A charging control unit 112 Charger 113 Current detection unit 114 Charging current control section 115 Remaining amount detection unit 122, 122A Abnormality detection section 116, 117 connector (first connector) 118, 119 connector (second connector) 120, 121 connector (third connector) 123 Switch (mode switching section) 124 Information Department A DC power supply output voltage B Input current of charging control unit C DC load input voltage D Secondary battery charging current E: Discharge current of secondary battery B´ Charger Input Voltage [Prior art documents] [Patent documents]

[0120] [Patent Document 1] Patent No. 4126329

Claims

1. a DC power supply that supplies a load current that is a DC current to a DC load; A secondary battery; a charge control unit electrically connected to the DC power supply, the DC load, and the secondary battery, and controlling charging of the secondary battery; a charger in the charging control unit that receives the DC power supply as an input and supplies a charging current to the secondary battery; a current detection unit that detects a current obtained by adding up the load current and the charging current of the DC power supply; a charging current control unit that performs variable charging control of the charging current so that the current detected by the current detection unit is within an allowable power range of the DC power supply; a remaining capacity detection unit that detects and integrates the charging current and discharging current of the secondary battery to determine the remaining capacity of the secondary battery; an abnormality location determination unit that determines an abnormality location based on input information of an output voltage of the DC power supply, an input current of the charging control unit, an input voltage of the DC load, and a charge / discharge current of the secondary battery; Equipped with Charging device.

2. a first connector that connects the DC power supply and the charging control unit; a second connector that connects the charging control unit and the DC load; a third connector that connects the charging control unit and the secondary battery; Equipped with the abnormality location determination unit determines, based on the input information, at least some of the abnormal locations among a failure of the DC power supply, a failure of the charger, a disconnection of the first connector, a disconnection of the second connector, a disconnection of the third connector, a failure of the secondary battery, and a failure of the DC load; The charging device according to claim 1 .

3. the abnormality part determination unit has an abnormality part determination table in which a correspondence relationship between a combination of patterns of the detection results of the input information and a plurality of abnormality part candidates is recorded, referring to the abnormality location determination table based on the input information, and identifying the abnormality location from among the plurality of abnormality location candidates; 3. The charging device according to claim 1 or 2.

4. a mode switching unit that switches between a charge mode and a discharge mode of the secondary battery; the abnormality portion determination unit forcibly switches to the discharge mode using the mode switching unit, and acquires a discharge current of the secondary battery as the input information; The charging device according to any one of claims 1 to 3.

5. a notification unit that notifies the abnormal part based on the determination result of the abnormal part determination unit; The charging device according to any one of claims 1 to 4.

6. a DC power supply that supplies a load current that is a DC current to a DC load; A secondary battery; a charge control unit electrically connected to the DC power supply, the DC load, and the secondary battery, and controlling charging of the secondary battery; a charger in the charging control unit that receives the DC power supply as an input and supplies a charging current to the secondary battery; a remaining capacity detection unit that detects and integrates the charging current and discharging current of the secondary battery to determine the remaining capacity of the secondary battery; an abnormality location determination unit that determines an abnormality location based on input information of an output voltage of the DC power supply, an input voltage of the charger, an input voltage of the DC load, and a charge / discharge current of the secondary battery; A charging device having:

7. An image forming apparatus comprising the charging device according to any one of claims 1 to 6.

8. a DC power supply that supplies a load current that is a DC current to a DC load; A secondary battery; a charge control unit electrically connected to the DC power supply, the DC load, and the secondary battery, and controlling charging of the secondary battery; a charger in the charging control unit that receives the DC power supply as an input and supplies a charging current to the secondary battery; A charging method for a charging device comprising: a current detection step of detecting a current obtained by summing the load current and the charging current of the DC power supply; a charging current control step of variably controlling the charging current so that the current detected in the current detection step is within an allowable power range of the DC power supply; a remaining capacity detection step of detecting and integrating the charging current and discharging current of the secondary battery to grasp the remaining capacity of the secondary battery; an abnormality location determination step of determining an abnormality location based on input information of an output voltage of the DC power supply, an input current of the charging control unit, an input voltage of the DC load, and a charge / discharge current of the secondary battery; Including, Charging method.

Images