JP7743783B2 - Charging device, charging method, and image forming apparatus - Google Patents

Description

The present invention relates to a charging device, a charging method, and an image forming device.

A charging device is known that charges a secondary battery using surplus power, other than the power supplied to the load, from a power source with limited power supply.

Patent Document 1 discloses a configuration for charging a secondary battery by varying the charging current according to the load, thereby maximizing the power supply capacity of the power source and shortening the charging time of the secondary battery.

However, if an abnormality occurs in the charging device, it may not be possible to determine the cause (identify the abnormality, including a loose connector), and non-faulty modules may also be replaced at the same time.

The purpose of this invention is to make it possible to identify the cause of an abnormality when it occurs in a charging device.

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 electrically connected to the DC power supply, the DC load, and the secondary battery and that 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 the sum of the load current and the charging current of the DC power supply; a charging current control unit that variably 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 charge detection unit that detects and integrates the charging current and discharging current of the secondary battery to determine the remaining charge of the secondary battery; and an abnormality determination unit that determines the location of an abnormality based on input information such as 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.

If an abnormality occurs in the charging device, the cause can be identified.

FIG. 1 is a diagram illustrating an example of the configuration of an image forming apparatus according to an embodiment. Power supply configuration diagram inside image forming device A diagram illustrating the basic operation of a conventional charging device. Functional block diagram of a charging device according to a first embodiment FIG. 10 is a diagram showing an example of an abnormality location determination table. Diagram explaining the operation when the abnormality is in the DC power supply Diagram explaining operation when the abnormality is in the charger FIG. 10 is a diagram illustrating the operation when the abnormality is caused by a disconnection of the first connector. A diagram explaining the operation when the abnormality is caused by the second connector coming loose. A diagram explaining the operation when the abnormality is caused by the third connector coming loose. A diagram explaining the operation when the abnormality is in the secondary battery Diagram explaining operation when the abnormality is in a DC load Flowchart of abnormality location determination process Functional block diagram of a charging device according to a second embodiment Functional block diagram of a charging device according to a third embodiment

Embodiments will be described below with reference to the accompanying drawings. To facilitate understanding, identical components in each drawing will be assigned the same reference numerals wherever possible, and duplicate descriptions will be omitted.

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

<Configuration of Image Forming Apparatus>
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.

The 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 save and distribute input images (documents scanned by the scanner function, and images input by the printer or fax function).

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

The image forming apparatus 100 is an electrophotographic image forming apparatus that adheres toner to an electrostatic latent image written by selectively exposing the surface of a charged photoreceptor, and then transfers the adhered toner to a recording medium such as paper.

As shown in FIG. 1, the image forming device 100 has an operation panel 1, a start switch 2, a controller 3 that controls the image forming device 100 based on operation inputs from the operation panel 1, a reading unit 4 that reads the original, an engine control unit 5 that generates control signals based on the reading results 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.

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

When the user presses the start switch 2 while the image forming device 100 is powered off, the start switch 2 starts the image forming device 100. Furthermore, when the user presses the start switch 2 while the image forming device 100 is powered on, that is, while the image forming device 100 is started up, the image forming device is turned off. In this way, the start switch 2 may be pressed by the user to turn the image forming device 100 on/off, but this is not limited to this, and the image forming device 100 may also be turned on/off based on instructions received from an external device.

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

A specific example of the controller 3 is a controller board that has a circuit mounted thereon that controls the image forming apparatus 100. This circuit includes, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), a RA (Read Only Memory), and the like.
The image forming apparatus 100 is controlled by a CPU that uses the RAM as a working area and executes programs stored in the ROM and HDD (Hard Disc Drive).

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

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.

The printer unit 6, which serves as the image forming section, includes 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 unit 4 and writes an electrostatic latent image onto the photosensitive member, a developing member 64 that develops the written latent image with toner, a conveyor belt 65 that conveys the recording medium on which the toner image is formed, and a fixing unit 66 that fixes the toner on the recording medium to the recording medium, thereby forming a toner image on the recording medium.

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

The transport unit 8, which serves as the paper feed transport section, has various rollers and transports recording media stored in paper feed cassettes 7A and 7B to the printer unit 6.

Here, the flow of image formation on image forming device 100 will be explained using copy mode as an example. First, the user operates the function switching keys on operation panel 1 to sequentially select and operate the copy function, printer function, and facsimile function of image forming device 100. When the copy function is selected, the device enters copy mode; when the printer function is selected, the device enters printer mode; and when the facsimile function is selected, the device enters facsimile mode.

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

The outer peripheral surface of photoconductor drum 61 is uniformly charged in the dark by charging member 62, and then exposed to light (indicated by dotted arrow A in FIG. 1 ) from writing unit 63, resulting in an electrostatic latent image being formed on the outer peripheral surface of photoconductor drum 61. Developing member 64 visualizes this electrostatic latent image with toner, thereby forming a toner image on photoconductor drum 61. The toner image formed on photoconductor drum 61 is transferred to a recording medium on conveyor belt 65. Then, fixing unit 66 heats and melts the toner in 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 image forming apparatus 100.

Note that while the printer unit 6 has been described as forming images using a monochrome electrophotographic method, the image formation method is not limited to these and may also be a color electrophotographic method or an inkjet method.

Furthermore, the above-mentioned 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 that control circuit. In this case, the control circuit of the controller 3 and the control circuit of the operation panel 1 are connected so that they can communicate with each other, and the controller 3 controls the entire image forming apparatus 100, including the operation panel 1.

Note that the controller 3, engine control unit 5, printer unit 6, paper feed cassettes 7A and 7B, and transport unit 8 are located inside the exterior of the image forming device 100, but Figure 1 shows the interior in a see-through manner.

Figure 2 is a diagram of the power supply configuration within the image forming device 100. It shows the image forming device 100 connected to a commercial power source.

The image forming apparatus 100 has an AC (Alternating Current) control unit 9 and a DC power supply 10. The image forming apparatus 100 also has a charging device 101 and a secondary battery 102.

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

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

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

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

The operation of the image forming apparatus 100 with the power supply configuration shown in Figure 2 will be described. When the image forming apparatus 100 is receiving normal power supply from an external power source such as a commercial power source, power from the DC power supply 10 is supplied to the controller 3. The amount of power required varies depending on the operation of the controller 3, so surplus power not used in the operation of the controller 3 is supplied to the secondary battery 102, which charges the secondary battery 102.

When a power outage occurs due to a disaster or other reason, meaning that the power supply from the external power source that is normally supplied is cut off, power is supplied from the secondary battery 102 to the DC power supply 10 of the image forming device 100. In other words, the secondary battery 102 functions as an auxiliary power source for the DC power supply 10.

Here, by giving the controller 3 the ability to control the operation panel 1 and the facsimile, the controller 3 can operate even during a power outage, receive facsimile data, and store it on the image forming device 100's HDD (Hard Disk Drive). Then, when power is supplied by a UPS (Uninterruptible Power Supply) capable of supplying AC power, or when the power is restored after a power outage, the stored facsimile data can be printed out.

<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 the 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.

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

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

As shown in FIG. 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.

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).

The charging control unit 111 has a charger 112, a current detection unit 113, a charging current control unit 114, and a remaining charge detection unit 115.

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 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. Note that 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 secondary battery 102 via the charging control unit 111; within this current direction, the DC power supply 10 side is referred to as the upstream side, and the DC load 103 side is referred to as the downstream side.

The current detection unit 113 detects the sum of the load current and charging current of the DC power supply 10 (the output 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, charging current control unit 114, and charger 112 on the downstream side.

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, which is notified from, for example, the controller 3. When the image forming apparatus 100 is in silent mode (energy saving, standby), the allowable power is small, and when in 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.

The remaining charge detection unit 115 detects and integrates the charging current and discharging current of the secondary battery 102 to determine the remaining charge of the secondary battery 102 (remaining charge detection step). The remaining charge 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.

<Configuration of Main Parts of First Embodiment>
The essential configuration of the first embodiment will be described with reference to FIGS.

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

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

The abnormality location determination unit 122 monitors whether an abnormality has occurred in the charging device 101, and if an abnormality occurs, determines the location of the abnormality. The abnormality location determination unit 122 receives as input 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, and performs the above monitoring and determination.

The input current B of the charging control unit 111 is obtained by acquiring the current value between the current detection unit 113 and the charging current control unit 114, as shown in FIG. 4, for example. The charging current D and discharging current E of the secondary battery 102 are obtained by acquiring the charging current and discharging current information held by the remaining charge detection unit 115 for detecting the remaining charge, as shown in FIG. 4, for example. The abnormality location determination unit 122 may also acquire the operating status of the controller 3 as input information.

Based on the above input information, the abnormality location determination unit 122 determines the abnormality locations 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 charging control unit 111), a disconnection of the second connector (connector 118 or connector 119 connecting the charging control unit 111 and DC load 103), a disconnection of the third connector (connector 120 or connector 121 connecting the charging control unit 111 and secondary battery 102), a failure of the secondary battery 102, or a failure of the DC load 103.

The abnormality location determination unit 122 may be configured to determine at least some of the above-mentioned abnormality location candidates.

The abnormal part determination unit 122 also has an abnormal part determination table that records the correspondence between combinations of patterns of the detection results of the above-mentioned input information and multiple candidate abnormal parts. The abnormal part determination unit 122 can identify an abnormal part from multiple candidate abnormal parts by referring to the abnormal part determination table based on the input information.

Figure 5 is a diagram showing an example of an abnormality location determination table. In the example of Figure 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 patterns of whether or not this input information can be detected, eight types of detection results are included: "No abnormality," "Fault in the DC power supply 10," "Fault in the charger 112," "Disconnection of the first connector," "Disconnection of the second connector," "Disconnection of the third connector," "Fault in the secondary battery 102," and "Fault in the DC load 103." In the table of Figure 5, cases where each piece of input information can be detected are indicated with "◯," and cases where it cannot be detected are indicated with "X."

In this embodiment, the abnormality location determination unit 122 identifies an abnormality location from among multiple candidate abnormality locations by referring to the abnormality location determination table illustrated in FIG. 5 based on input information. However, a configuration without using an abnormality location determination table is also possible. For example, the abnormality location determination unit 122 may have a predictor that outputs information identifying an abnormality location when it receives the above input information, and the input/output relationship of the predictor may be obtained in advance using a machine learning technique, and the trained predictor may be used to determine an abnormality location.

The switch 123 is disposed between the current detection unit 113 and the DC load 103, and upstream of the charger 112. By switching between an on state and an off state, the switch 123 switches 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.

When switch 123 is in the on state, the charging mode is set so that 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 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 discharging mode is set so that the discharging current from the secondary battery 102 is supplied to the DC load 103 via the charging control unit 111. In other words, switch 123 functions as a mode switching unit that switches between the charging mode and discharging mode of the secondary battery 102.

The switch 123 is connected to the abnormal part determination unit 122 and operates in response to commands from the abnormal part determination unit 122. The abnormal part determination unit 122 switches the switch 123 between an on state and an off state during the abnormal part determination process. The timing at which the abnormal part determination unit 122 switches the switch 123 will be described later with reference to Figure 13.

The switch 123 is only required to be an 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 charger 112 downstream in the current direction, and may be configured to use an element other than a switch that has a similar function.

The operation of the abnormality point determination unit 122 is outlined below, for example. When any device in the DC load 103 abnormally stops, a signal to start determination is sent from the controller 3 to the abnormality point determination unit 122. In response to receiving this signal, the abnormality point determination unit 122 detects the voltage and current values at the points (A to E) shown in Figure 5. Based on each detected value, it refers to the abnormality point determination table in Figure 5 and determines which pattern in the determination table the combination of detection results corresponds to.

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 kind of abnormality, there will be points among the detection points (A to E) where no value can be detected. For example, if no detection is possible at A, B, and D, the combination of detection results will be "Pattern 1," and the cause of the abnormality can be determined to be "fault in DC power supply 10." Note that if the combination of detection results does not correspond to a pattern in the abnormality point determination table shown in Figure 5, it will be determined that there is an abnormality in another point.

When the abnormality location determination unit 122 detects the discharge current E, it turns off the switch 123, cuts off the power supply from the DC power supply 10, and forcibly switches to discharging operation. This forcibly switches the operating mode of the charging device 101 to discharging mode.

Next, we will explain each abnormality pattern individually with reference to Figures 6 to 12.

Figure 6 is a diagram explaining the operation when the abnormality is in the DC power supply 10. Figure 6 (A) is a diagram showing the operation of the charging device 101 when the switch 123 is in the on state, and Figure 6 (B) is a diagram showing the operation of the charging device 101 when the switch 123 is in the on state. The same applies to the following Figures 7 to 12.

As shown in Figure 6, when the DC power supply 10 is faulty, the output voltage A of the DC power supply 10 is undetectable (x) because the DC power supply 10 is not operating and does not output any voltage. The input current B of the charging control unit 111 is undetectable (x) because the DC power supply 10 is not operating and no power is supplied to the charging control unit 111. The input voltage C of the DC load 103 is detectable (o) because the DC power supply 10 is not operating and power is supplied from the secondary battery 102 to the load 103. The charging current D at the connection between the charging control unit 111 and the secondary battery 102 is undetectable (x) because no power is 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 between the charging control unit 111 and the secondary battery 102 is detectable (o) because power is supplied from the secondary battery 102 to the DC load 103. The detection patterns for these signals A to E are the same whether switch 123 shown in Figure 6(A) is in the on state or switch 123 shown in Figure 6(B) is in the off state.

Therefore, if the DC power supply 10 is faulty, the combination of input information A to E acquired by the abnormality location determination unit 122 corresponds to "Pattern 1" in the abnormality location determination table in Figure 5, and the abnormality location determination unit 122 can determine that the DC power supply is faulty.

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

Figure 7 is a diagram explaining operation when the abnormality is in the charger 112. As shown in Figure 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 is operating and outputting 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 for these signals A to E are the same whether switch 123 shown in Figure 7(A) is in the on state or switch 123 shown in Figure 7(B) is in the off state.

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

If the charger 112 is faulty, and switch 123 shown in Figure 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 switch 123 shown in Figure 7(B) is in the off state, a discharge mode is entered in which a discharge current is supplied from the secondary battery 102 to the DC load 103.

Figure 8 is a diagram explaining operation when the abnormality is due to the first connector being disconnected. As shown in Figure 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 disconnected 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 disconnected and no power is 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 undetectable (×) because the DC power supply 10 and the charging control unit 111 are disconnected and the charger 112 is not operating. Discharge current E at the connection 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 Figure 8 (A) is in the on state or switch 123 shown in Figure 8 (B) is in the off state.

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

When the first connector is unplugged, power is not supplied from the DC power source 10 to the charging control unit 111, so the device 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 Figure 8 (A) is in the on state or the switch 123 shown in Figure 8 (B) is in the off state.

Figure 9 is a diagram explaining operation when the abnormality is due to the second connector being disconnected. As shown in Figure 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 no power is 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. Discharge current E at the connection between charge control unit 111 and secondary battery 102 is undetectable (x) because charge control unit 111 is not connected to DC load 103 and power is not supplied to DC load 103. The detection patterns for signals A to E are the same whether switch 123 shown in Figure 9 (A) is in the on state or switch 123 shown in Figure 9 (B) is in the off state.

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

When the second connector is unplugged, if switch 123 shown in Figure 9 (A) is in the on state, the charging control unit 111 and DC load 103 are disconnected, so no load current is supplied to the DC load 103, and charging current is supplied from the charger 112 to the secondary battery 102, resulting in charging mode. On the other hand, if switch 123 shown in Figure 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.

Figure 10 is a diagram explaining operation when the abnormality is due to the third connector being unplugged. As shown in Figure 10, when the third connector (connector 120 or connector 121) is unplugged, 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. Discharge current E at the connection between charge control unit 111 and secondary battery 102 is undetectable (x) because charge control unit 111 and secondary battery 102 are disconnected and power is not supplied from secondary battery 102 to DC load 103. The detection patterns for signals A to E are the same whether switch 123 shown in Figure 10(A) is in the on state or switch 123 shown in Figure 10(B) is in the off state.

Therefore, if the third connector is unplugged, the combination of input information A to E acquired by the abnormality point determination unit 122 corresponds to "Pattern 5-1" in the abnormality point determination table in Figure 5, and the abnormality point determination unit 122 can determine that the "third connector is unplugged."

When the third connector is unplugged, if the switch 123 shown in Figure 10 (A) is on, a load current is supplied from the DC power supply 10 to the DC load 103, but because the charging control unit 111 and secondary battery 102 are not connected, no charging current is supplied from the charger 112 to the secondary battery 102. On the other hand, if the switch 123 shown in Figure 10 (B) is off, no load current is supplied from the DC power supply 10 to the DC load 103, and because the charging control unit 111 and secondary battery 102 are not connected, no charging current is supplied from the charger 112 to the secondary battery 102. As a result, the secondary battery 102 is neither charged nor discharged.

Figure 11 is a diagram explaining operation when the abnormality is in the secondary battery 102. As shown in Figure 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 charging to the secondary battery 102 is not possible. 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 for these signals A to E are the same whether switch 123 shown in Figure 11(A) is in the on state or switch 123 shown in Figure 11(B) is in the off state.

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

Note that the detection result pattern will be the same when the secondary battery 102 is faulty as shown in Figure 11 and when the third connector is unplugged as shown in Figure 10, but the worker can first check whether the third connector is unplugged, and if this is not the cause, determine that the secondary battery 102 is faulty. Due to the configuration of the charging device 101, the third connector (connectors 120 and 121) and the secondary battery 102 are located close to each other, so the above determination also has the effect of reducing work time.

If the secondary battery 102 is faulty, and switch 123 shown in Figure 11 (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 can be supplied from the charger 112 to the secondary battery 102. On the other hand, when switch 123 shown in Figure 11 (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 can be supplied from the charger 112 to the secondary battery 102. As a result, the secondary battery 102 is neither charged nor discharged.

Figure 12 is a diagram explaining operation when the abnormality is in the DC load 103. As shown in Figure 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. Note that in this case, the input voltage C is supplied to a location other than the faulty location within 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 source 10 to the charging control unit 111, causing the charger 112 to operate. The discharging current E at the connection 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 for these signals A to E are the same whether the switch 123 shown in Figure 12(A) is in the on state or the switch 123 shown in Figure 12(B) is in the off state.

Therefore, if the DC load 103 is faulty, the combination of input information A to E acquired by the abnormality location determination unit 122 corresponds to "Pattern 6" in the abnormality location determination table in Figure 5, and the abnormality location determination unit 122 can determine that there is a "load failure."

In addition, pattern 6 is the same pattern as normal, in which all input information is detectable (◯). However, because the abnormality location determination unit 122 performs determination processing after the device-side controller 3 of the DC load 103 detects an abnormality, it is possible to distinguish between normal and abnormal conditions.

When the DC load 103 is faulty, if the switch 123 shown in Figure 12(A) is in the on state, a load current is supplied from the DC power supply 10 to the DC load 103 other than the faulty part, and a charging mode is entered in which a charging current is supplied from the charger 112 to the secondary battery 102. On the other hand, if the switch 123 shown in Figure 12(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 other than the faulty part.

Figure 13 is a flowchart of the abnormality location determination process. Each step in the flowchart in Figure 13 is performed by the abnormality location determination unit 122.

When the charging device 101 is in a normal state, each device in the DC load 103 is operating normally (NO in step S01), so the charging device waits until an abnormality occurs. On the other hand, if an abnormality occurs in the charging device 101, one of the devices in the DC load 103 will abnormally stop (YES in S01), and the controller 3 will send a signal to the abnormality location determination unit 122 to instruct it to start determination (step S02).

In response to receiving this signal, the abnormality determination unit 122 detects the occurrence of an abnormality and proceeds to step S03, where it begins the abnormality determination process (abnormality determination step).

First, switch 123 is switched on (step S03), power is supplied from DC power supply 10 to charging control unit 111, and charging mode for secondary battery 102 is normally in operation. In this state, the 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).

Next, the switch 123 is switched to the OFF state (step S08), preventing power supply from the DC power source 10 to the charge control unit 111, and setting the secondary battery 102 in a discharge mode under normal circumstances. In this state, the discharge current E of the secondary battery 102 is detected (step S09). Then, the switch 123 is returned to the ON state (step S10). In other words, the abnormality location determination unit 122 forcibly switches the secondary battery 102 to a discharge mode via the switch 123, and acquires the discharge current E of the secondary battery 102 as input information.

Next, based on the combination of detection results (detected (◯) or not (X)) for signals 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.

If the detection results of 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 a "fault in the DC power supply 10" (step S12), and this control flow ends.

If the detection results of signals 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), the cause of the abnormality is determined to be a "fault in the charger 112" (step S14), and this control flow ends.

If the detection results of signals 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 ends.

If the detection results of signals 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 ends.

If the detection results for signals 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), the cause of the abnormality is determined to be "disconnection of the third connector" (step S20), and this control flow ends.

If the detection results of signals 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), the cause of the abnormality is determined to be a "fault in the secondary battery 102" (step S22), and this control flow ends.

If the detection results of signals 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), the cause of the abnormality is determined to be a "fault in the DC load 103" (step S24), and this control flow ends.

If the detection results for signals 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 ends.

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 such as 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 discharging current E of the secondary battery 102. With this configuration, the cause of the abnormality can be identified by aggregating and analyzing various types of information within the charging device 101, making it easy to determine the cause if an abnormality occurs in the charging device.

In the past, when an abnormality occurred in the charging device 101, it was not possible to isolate the cause, and investigating the cause in the field required processes such as disassembling the device, resulting in long downtime at the customer's end. In contrast, the charging device 101 of this embodiment analyzes the various input information described above, making it possible to easily isolate the cause of the abnormality without disassembling the device, thereby reducing downtime at the customer's end when an abnormality occurs in the charging device.

In addition, in the past, if the cause of a malfunction was unknown, non-faulty modules would also be replaced during service repairs, resulting in unnecessary parts consumption and increased parts purchasing costs. In contrast, the charging device 101 of this embodiment makes it possible to easily isolate the cause of the malfunction by analyzing the various input information described above, thereby reducing the wasteful consumption of service-owned parts.

In addition, in the charging device 101 of the first embodiment, the abnormality location determination unit 122 has an abnormality location determination table that records the correspondence between combinations of patterns of detection results of input information A to E and multiple candidate abnormality locations, and identifies the abnormality location from among the multiple candidate abnormality locations by referencing the abnormality location determination table based on the input information. With this configuration, the abnormality location can be easily and quickly identified based on the input information simply by referencing the abnormality location determination table, which has input and output relationships associated in advance.

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.

As shown in FIG. 14, the charging device 101A of the second embodiment includes a notification unit 124 that notifies the abnormality location based on the results of the determination by the abnormality location determination unit 122. The notification unit 124 can notify the service personnel of the charging device 101A of information about the abnormality location identified by the abnormality location determination unit 122 using, for example, text information or audio information, and urge them to perform repairs.

In this way, by including the notification unit 124, the charging device 101A of the second embodiment can quickly and clearly notify service personnel of the location of the abnormality, further shortening repair time.

[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.

As shown in FIG. 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 or a charging current control unit 114. In other words, the charging device 101B of the third embodiment is configured so that the charging control unit 111A does not vary the charging current.

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. In other words, the abnormality location determination unit 122A determines the abnormality location based on input information: 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.

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

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-mentioned 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-mentioned specific examples can be combined in different ways as appropriate, as long as no technical contradictions arise.

REFERENCE SIGNS LIST 10 DC power supply 100 Image forming apparatus 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 unit 115 Remaining charge detection unit 122, 122A Abnormal location determination unit 116, 117 Connector (first connector)
118, 119 Connector (second connector)
120, 121 Connector (third connector)
123 Switch (mode switching section)
124 Notification unit A Output voltage of DC power supply B Input current of charging control unit C Input voltage of DC load D Charging current of secondary battery E Discharging current of secondary battery B' Input voltage of charger

Patent No. 4126329

Claims (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 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. 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 . 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. 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. 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. 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: An image forming apparatus equipped with the charging device described in any one of claims 1 to 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 charging method for a charging device, comprising: a current detection step of detecting a current obtained by adding up 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.