JP4600962B2 - FEEDING DEVICE HAVING INTERLOCK CIRCUIT AND IMAGE FORMING DEVICE - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a power supply apparatus having an interlock circuit and an image forming apparatus using the same. Specifically, although not intended to be limited to this, the present invention relates to an interlock circuit provided for protecting an operator of office equipment or the like, and more particularly, to detection of a contact abnormality of an electric relay used in the interlock circuit.
[0002]
[Prior art]
For example, in office equipment, an interlock circuit has been conventionally used. For example, an interlock switch linked to opening / closing of the front door of the equipment is used to control the DC power supply voltage of a load driving circuit device such as a motor. By opening and closing, a dangerous operation state for the operator does not occur when the front door or the like is opened. As a result, even if the power of the device is turned on, if the front door or the like is opened, the drive voltage of the load is not applied, that is, the load does not move. Accidents that occur can be prevented.
[0003]
In general, in order to realize this configuration, an interlock switch that opens and closes the electrical circuit by opening and closing the wiring of the power supply voltage line that you want to open and close as an interlock circuit to its door The connected power supply voltage line is connected serially.
[0004]
However, in the case of this method, if the load current to be interrupted as an interlock circuit is large, it will be diverted to the vicinity of the door. Increased noise emission is less desirable from an EMC perspective. In addition, when there are a plurality of doors as an interlock mechanism, and when there are a plurality of circuits to be shut off, they need switches for the combination. For example, there are a front door, a left door, and a right door, and the circuit can be shut off when any of them is opened. For example, when there are 3 systems of 5V system, 24V system, 1 and 24V system 2, 3 × 3 = 9 Things need to be switched.
[0005]
For this reason, as a method other than the above, there is a method in which an electric relay is used to cut off the power supply voltage line of the load system and the drive circuit of the relay is cut off by an interlock switch (door switch). In this case, as shown in the example of the three shut-off points and the three power sources, the 24V system 1 can be opened and closed by a door switch, and a relay drive circuit is also assigned. As the relay to be driven, a relay with two circuits is used. According to this configuration, where there is a small number of components such as three door switch switches for opening and closing the 24V system 1 (relay drive circuit) and one relay for opening and closing the 24 system 2 and 5V, where the door is Even if it is opened, an interlock circuit that can cut off all three power sources can be realized. In this case, three door switches are connected in series and are inserted between the 24V system 1 and the electric coil of the relay. Of course, it is not necessary to limit the relay drive power supply to the interlock voltage (24V system, 24V system 2, 5V).
However, in general, in circuit switching parts such as switches and relays that open and close the conductor contact piece, when the contact piece closes, an inrush current flows into the capacitive load provided on the load side, and an arc or the like is generated by this inrush current. There is a problem that the contacts are welded. Even in a switch circuit using a semiconductor switch, an inrush current may cause the semiconductor switch to malfunction or break down. In particular, in the case of relays, in general, compared to a switch having the same current capacity, many of them have low characteristics against inrush current. For this reason, various studies have been made to further suppress the inrush current.
[0006]
For example, in Japanese Patent Laid-Open No. 2000-215772, a semiconductor switch is inserted in a power supply line that is opened and closed by a relay, and when the power supply line is closed, first, an electric coil of the relay is energized to close the contact piece, and a delay drive circuit Proposed to turn on the semiconductor switch after a predetermined delay time. According to this, since no current flows through the relay contact when the relay is turned on (closed), it is difficult to cause welding.
[0007]
[Problems to be solved by the invention]
From the viewpoint of protecting the contacts of the interlock circuit switching parts, various studies have been made such as a method for preventing inrush current itself and a method for suppressing inrush current.
[0008]
For example, as a method for preventing the former inrush current itself, a technique described in Japanese Patent Laid-Open No. 2000-215772 is cited as an example of dealing with an interlock relay, and a method for suppressing the latter is a current limiting circuit. Many known techniques have been announced, such as adding a load, and reducing the load capacity is one method.
[0009]
However, these conventional methods are countermeasures based on the premise that “the contact current should not occur because the inrush current is suppressed, and contact welding will not occur”. Not considered.
[0010]
For example, impurities such as silicon oil may be mixed in the contact area and the contact will not close, or an unexpected inrush current will increase due to some load abnormality, resulting in contact welding. Is the case. In the case of the latter example, there is no problem if a countermeasure is taken so as not to generate an inrush current on the circuit as in the technique described in Japanese Patent Application Laid-Open No. 2000-215772, but the cost increases due to the additional circuit. There is also a problem.
[0011]
In the interlock circuit for protecting the operator, not to mention that there is no abnormality, it is desirable that even if there is an abnormality, it is desirable that a dangerous operation state does not occur for the operator.
[0012]
By the way, when using an interlocking electrical relay, when an interlock switch for energizing the electrical relay is opened, and the electrical relay is switched from on to off, the opening of the relay contact may be delayed. For example, in the case of light contact welding, the delay of switching from closing to opening of the contact piece of the electric relay becomes large. For heavy contact welding, the delay is infinite. When impurities adhere to the contact portion, the delay in switching from opening to closing of the switch increases or becomes infinite. Therefore, by monitoring the delay amount, it is possible to grasp the malfunction of the switch means or its tendency.
[0013]
However, the timing at which the relay contacts open varies depending on the contact transfer condition, but also changes depending on the state of the connected load. For example, when no current is applied and when a large current is applied, the opening is slower when the large current is applied. This is because even if an attempt is made to release the contact piece while a current is flowing, a discharge phenomenon occurs, so that the current continues during that time and the contact piece is apparently not open. This phenomenon becomes more pronounced as the energization current value increases.
[0014]
Also, the interlock switch that energizes the interlock electrical relay closes, and the delay in closing the relay contact when the electrical relay switches from off to on varies depending on the contact transfer condition. In addition, it varies depending on the state of the connected load. For example, when there is a capacitive load, the delay in closing the relay contact is shorter when there is a capacitive load. This is because when there is a capacitive load, an inrush current will flow, and in the contact state where current is to flow, when the contact piece approaches, a discharge phenomenon will occur before it comes into full contact. This is because current conduction starts during that time, and the contact piece apparently turns on. This phenomenon becomes more prominent as the energization current value is larger, that is, as the capacitive load is larger.
[0015]
The present invention provides a power supply having an interlock circuit including switch means for energizing a power supply line in response to a close instruction signal and shutting off when the close instruction signal disappears, and means for shutting off the close instruction signal to the switch means. In an apparatus or an image forming apparatus using the same,
The first purpose is to detect the malfunction of the switch means or its tendency, and the second purpose is to increase the detection accuracy, and early detection of malfunction of the electrical relay contact of the interlock circuit. The third object is to do this automatically, and the automatic notification of malfunctions is the fourth and fifth objects, respectively.
[0016]
[Means for Solving the Problems]
(1) Inserted in the power supply line from the power source to the load, One Close instruction signal Supply In response to plural Feed line Individually Energize and close instruction signal Supply stops When Energize individually Cut off Duplex Switch means (86); and Duplex Closing instruction signal to switch means (86) Supply Shut off Shut off A power supply apparatus having an interlock circuit comprising means (73);
Said Duplex Connected to the power supply via switch means (86) Each connected to each power line Corresponding to the load amount each Set reference values (T1s, T2s) Reference value setting Means (51);
Said compound The closing instruction signal to the switch means (86) Supply start From and in response to it Duplex By switch means (86) each Feed line Delay of each energization to Detecting total (T1, T2) Delay detection Means (51); and
Broadcast corresponding to the length of the detected delay (T1, T2) with respect to the reference value (T1s, T2s) Notification Means (51, 20);
A power supply apparatus having an interlock circuit (First embodiment: FIG. 5) .
[0017]
(2) inserted in the power supply line from the power source to the load, One Close instruction signal To supply pls respond plural Feed line Individually Energize, the close instruction signal Supply stops When Energize individually Cut off Duplex Switch means (86); and Duplex Closing instruction signal to switch means (86) Supply Shut off Shut off A power supply apparatus having an interlock circuit comprising means (73);
Said Duplex Connected to the power supply via switch means (86) Each connected to each power line Corresponding to the load amount each Set the reference value Reference value setting Means (51);
Said compound The closing instruction signal to the switch means (86) Supply stop From and in response to it Duplex By switch means (86) each Feed line Stop each power supply to Detect delay Delay detection Means (51); and
A notification corresponding to the length of the detected delay with respect to the reference value is given. Notification means;
A power supply apparatus having an interlock circuit (Third embodiment: FIG. 9) .
[0018]
In addition, in order to make an understanding easy, the code | symbol of the corresponding element or the corresponding matter of the Example shown in drawing and mentioned later in parentheses is added for reference. The same applies to the following.
[0019]
(1) and (2) above According to the above, the delay detected by the delay detecting means (51) corresponds to the tendency of the switch means (86) to malfunction. The greater the delay, the higher the possibility of malfunction. For example, in the case of light contact welding, the delay in switching from switch closing to opening increases. For heavy contact welding, the delay is infinite. When impurities adhere to the contact portion, the delay in switching from opening to closing of the switch increases or becomes infinite. Therefore, by monitoring the delay amount, it is possible to grasp the malfunction of the switch means or its tendency.
[0020]
When the switch means (86) is switched from closed to open, if the load connected to the power supply is large, the delay in switching from the closed to open is large, so take a long reference value and if the load is small, Since the switching delay is small, it is possible to cope with a short reference value. Or, when the load connected to the power supply is large when switching the switch means (86) from open to closed, the delay in switching from open to closed is small, so the reference value is short and the load is small Since the delay in switching is large, it is possible to cope with a long reference value. In any aspect, the state of contact transfer can be grasped more accurately.
[0021]
Shut off Means (73) For example, for a plurality of power supply voltages to be turned OFF / ON by opening / closing a door switch, instead of using a plurality of switch means, for example, an electrical relay, one system is turned OFF / ON by a door switch. Configuration to turn off / on the remaining multiple systems with one dual electric relay operated in one system In The The dual electric relay includes a plurality of sets of switch assemblies of two contacts and their open / close contacts, and one electric coil for simultaneously opening and closing the open / close contacts. If there are three door opening / closing locations, three door switches are connected in series and inserted between the power supply voltage of the one system and the electric coil of the dual electrical relay, and each switch assembly is connected to the remaining plurality. Insert each power supply voltage line of the system. With this configuration, each power supply voltage line of multiple systems can be turned off / on by one electrical relay, and all of the power supply voltage lines of multiple systems are routed close to the door. I'm sorry.
[0022]
Duplex switch means (86) For example, it is rare that the malfunction of the duplex electrical relay appears at the same time with respect to the opening and closing of a plurality of power supply lines. In most cases, there is a difference in the progress of malfunction, or one Only will be malfunctioning. At this time, a difference occurs in the change in operation delay between the power supply lines.
[0023]
Therefore, by individually monitoring the change in the switching delay of each power supply line detected by the delay detection means (51), it is possible to know the occurrence of malfunctions in each system individually, and the delay of those delays. By monitoring the change or the change in order, the malfunction of the switch means (86) can be known. Since the reference value is set in accordance with the load amount, such a malfunction can be grasped more accurately.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
(3) The notification means (51, 20) performs notification associated with the change when the order between the delays of the power supply lines is changed. (1) or (2) Power feeding device.
[0025]
In other words, in a relay with multiple circuits, depending on the load state, considering each time until the contact piece is turned off, monitoring whether it operates according to the sequence assumed in advance, is not limited to the state where the contact has moved to some extent. Although it is only a single circuit, it is possible to detect an abnormal state at the beginning of transfer. From this, (1) Or (2) This makes it possible to detect at an early stage in which a sign of abnormality appears, while realizing accurate detection of a delay shift in the form of.
[0026]
(4) The blocking means (73) is operated by an external force. From Non-action Switching to Is an electrical switch having an electrical contact that switches from open to closed or vice versa. For example, a door switch that opens and closes by opening or closing a door or cover The power feeding device according to any one of (1) to (3) above .
[0027]
According to this, when an external force is applied to the electric switch by the action of the operator, the opening and closing of the electric switch is switched, thereby switching the opening and closing of the switch means (86) such as the electric relay. By monitoring the delay amount detected by the delay detection means (51), it is possible to grasp the malfunction of the switch means (86) or its tendency.
[0028]
(4a) said Duplex The switch means (86) plural Feed line Each of To multiple inserted electrical contacts Each Come and go plural Electrical contact at the same time Includes electrical coils that are driven or disengaged Duplex An electrical relay (86).
[0029]
According to this, by monitoring the delay amount detected by the delay detection means (51), Duplex The malfunction or tendency of the electrical relay (86) can be grasped.
[0030]
(5) An electrostatic latent image is formed on the photosensitive member (114), the electrostatic latent image is visualized as a toner image by the developing device (120), and the toner image is directly or indirectly via an intermediate medium. In addition, in an image forming apparatus for transferring to transfer paper,
The In the device plural To the power supply line The power supply device according to any one of claims 1 to 4 is provided. An image forming apparatus.
[0031]
According to this, Of the power feeding device Delay test Start In response to the opening / closing of the door or front cover of the image forming apparatus, the stage (51) switches the contact / disengagement of the electrical contacts (a, b) of the electrical relay (86) from the switching. Automatically detect the delay until. The degree of this delay corresponds to the tendency of the electrical relay (86) to malfunction. When the electrical relay (86) is switched from closed to open, the greater the delay, the higher the possibility of malfunction. For example, in the case of light contact welding, the delay in switching from the switch closed to the open increases. For heavy contact welding, the delay is infinite. When impurities adhere to the contact portion, the delay in switching from opening to closing of the switch increases or becomes infinite. Therefore, by monitoring the delay amount, it is possible to grasp the malfunction or tendency of the electrical relay (86).
[0032]
When the load connected to the power supply is large when switching the electrical relay (86) from close to open, the delay in switching from close to open is large, so take a long reference value and when the load is small, Since the switching delay is small, it is possible to cope with a short reference value. Or, when the load connected to the power supply is large when switching the electrical relay (86) from open to closed, the delay in switching from open to closed is small, and therefore the reference value is short and the load is small. Since the delay in switching is large, it is possible to cope with a long reference value. In any aspect, the state of contact transfer can be grasped more accurately.
[0033]
(6) The device further reads the image of the document reading An original scanner for generating image data; and reading Image data , Means for processing image data for forming an electrostatic latent image on the photosensitive member;
[0034]
According to this, in the digital copying apparatus, the operation and effect of the above (5) can be obtained similarly.
[0035]
Other objects and features of the present invention will become apparent from the following description of embodiments with reference to the drawings.
[0036]
【Example】
-1st Example-
FIG. 1 shows the appearance of a multifunction copying machine according to an embodiment of the present invention. This multi-function copier is roughly an automatic document feeder [ADF] 30, an operation unit 20, a color scanner 10, a color printer 100, a relay unit 32, a stapler and a large amount of imaged paper. The stacker includes a finisher 34 with a shift tray, a duplex reversing unit 33, a paper feed bank 35, a large-capacity paper feed tray 36, and a 1-bin paper discharge tray 31.
[0037]
FIG. 2 shows the configuration of the color printer 100. Reference numeral 101 denotes a flexible photosensitive belt. The photosensitive belt 101 is installed between the rotating rollers 102 and 3 and is conveyed in the direction of arrow A (clockwise) in the figure by the rotational driving of the rotating roller 102. . In the figure, reference numeral 104 denotes a charging charger that uniformly charges the surface of the photosensitive belt 101, and reference numeral 105 denotes a laser exposure apparatus that is an image writing unit. In the figure, 106 is a color developing device, 106a is magenta, 106b is cyan, 106c is yellow, and 106d is a black developing unit.
[0038]
Further, reference numeral 109 in the figure denotes an intermediate transfer belt. The intermediate transfer belt 109 is installed on the rotation rollers 110-112 and is conveyed in the direction of arrow B (counterclockwise) in the figure by the rotation of the rotation roller 110. The photosensitive belt 101 and the intermediate transfer belt 109 are in contact with each other by a symbolless rotating roller portion of the photosensitive belt 101. On the intermediate transfer belt 109 side of the contact portion, a conductive bias roller 113 is in contact with the back surface of the intermediate transfer belt 110 under predetermined conditions.
[0039]
The photosensitive belt 101 is uniformly charged by a charging charger 104 and then exposed by scanning with a laser beam modulated by an image recording signal by a laser exposure device 105. As a result, an electrostatic latent image is formed on the photosensitive belt 101. Here, the image recording signal for modulating the laser beam is for each color (single color) obtained by decomposing a desired full color image into magenta, cyan, yellow, and black (Bk) color information. The formation of the electrostatic latent image and the development by the color in the developing devices 106a to 106d are repeated for the number of colors (for example, magenta, cyan, yellow, and black, a total of four times). The developed images (toner images) appearing by development are transferred onto the intermediate transfer belt 9 in a superimposed manner.
[0040]
That is, each single-color image (toner image) formed on the photosensitive belt 1 rotating in the direction of arrow A in the figure is synchronized with the photosensitive belt 101 on the intermediate transfer belt 109 rotating in the direction of arrow B in the figure. , Magenta, cyan, yellow, and black are sequentially superimposed and transferred by a predetermined transfer bias applied to the bias roller 113. The magenta, cyan, yellow, and black images superimposed on the intermediate transfer belt 109 are fed from the paper feed cassette 116a of the paper feed tray 116 to the paper feed roller 117, the transport roller pair 118a and 118b, and the registration roller pair 119a and 119b. After that, the images are collectively transferred onto the transfer paper conveyed to the transfer roller 114. After the transfer is completed, the toner image on the transfer paper is fixed (heat-pressed) on the transfer paper by the fixing device 120. As a result, a full-color image is completed, and the transfer paper is discharged to the paper discharge stack section 122 through the paper discharge roller pair 121a and 121b.
[0041]
In the figure, reference numeral 107 denotes a cleaning blade that always contacts the photosensitive belt 101 and wipes off the toner on the photosensitive belt 101. Reference numeral 115 denotes a cleaning device for the intermediate transfer belt 109, and the cleaning brush for the cleaning device 115. 115a is held at a position separated from the surface of the intermediate transfer belt 110 during the image forming operation, and a formed image is transferred onto the transfer paper described above and then brought into contact with the surface of the intermediate transfer belt 110.
[0042]
Further, the photosensitive belt 101, the charging charger 104, the intermediate transfer belt 109, and the cleaning devices 107 and 115 are integrally assembled into a process cartridge to form a unit.
[0043]
Reference numeral 108 denotes a toner adhesion amount sensor for detecting the toner adhesion amount on the photosensitive belt 101. The toner adhesion amount sensor 108 used this time generates and outputs a voltage Vs, that is, a detection signal corresponding to the amount of light received by the photodiode, in which the light emitting portion is an infrared light emitting diode and the diffuse reflected light receiving portion is a photodiode. That is, a toner density sensor that measures the amount of diffusely reflected light.
[0044]
Inside the fixing roller of the fixing device 120, there is a fixing heater (halogen lamp) 123C. The fixing heater 123C is energized by a fixing energizing circuit 85 (FIG. 4), whereby the fixing heater 123C generates heat and emits infrared rays. Occurs and heats the fixing roller.
[0045]
FIG. 3 shows an outline of the electric system of the copying machine shown in FIG. The copier mechanical control unit, that is, the main part of image reading and image forming process control includes one MPU (Micro Processing Unit) 51 on the main control board 50 and one CPU (Center Processing Unit) 12 on the scanner control board 11. Is used. The MPU 51 performs image-related sequence and fixing control and system-related control, and the CPU 12 performs scanner-related control. The MPU 51 and the CPU 12 are connected by an image data interface and a serial interface.
[0046]
In FIG. 3, 20 is an operation unit, 70 is an I / O control board equipped with an input / output electric circuit, 92 is an LD control board for controlling laser light for image exposure, 41 is a paper feed control board, 13 is A reading control board 90 on which the CCD is mounted is a mother board.
[0047]
A printer controller (board) 60 controls a printer function for printing a document of a host such as a personal computer or a word processor, and a combined operation mode of a copy, facsimile, and printer. Reference numeral 91 denotes an application expansion unit for realizing a composite function, which is a facsimile control unit (FCU) equipped with a FAX function. Reference numeral 80 denotes a DC power source / AC control board.
[0048]
4 shows an outline of a power supply system from the power supply device 80 to the fixing heater 123C, the I / O control board (input / output interface) 70, the main control board (main controller) 50, the motherboard 90 and the printer controller 60, and An outline of the printer controller 60 is shown.
[0049]
Referring to FIG. 4, the main control board 50 for controlling the image forming process includes an MPU 51, a CPU peripheral ASIC (Application Specific IC) 54, an image processing ASIC 53, an interface function with the printer controller 60, and an image data compression / decompression function. There is an I / F (interface) 52 having
[0050]
The printer controller 60 that controls the system includes a peripheral ASIC 64 having a communication function between the interface of the MPU 61 and the main control board 50 and the operation unit for realizing a composite function and an operation unit, and a memory control function, and others. .
[0051]
The document scanner 10 that optically reads a document condenses reflected light of lamp irradiation on the document on a light receiving element by a mirror and a lens. The light receiving element (CCD) is in the sensor board unit (SBU) 13, and the image signal converted into an electric signal in the CCD is converted into a digital signal, that is, read image data on the SBU 13. , SBU13 outputs the image to the image processing ASIC 53 on the main control board 50.
[0052]
The read image data from the SBU 13 is transferred to the image processing ASIC 53, and the image processing ASIC 53 performs signal deterioration due to quantization into an optical system and a digital signal (scanner signal deterioration: read image data due to scanner characteristics). The image data is transferred to the printer controller 60 and written into the memory MEM65. Alternatively, a process for printer output is performed and given to the LD control board 92 of the printer 100.
[0053]
That is, the image processing ASIC 53 outputs the read image data to the memory MEM 65 for reuse, and outputs it to the video data control (VDC) on the LD control board 92 without storing it in the memory MEM 65. -There are jobs that output images with the printer function. As an example of storing in the memory MEM65, when copying a plurality of originals, the scanner 10 is operated only once, the read image data is stored in the memory MEM65, and the stored data is read out a plurality of times. . As an example in which the memory MEM 65 is not used, when only one original is copied, the read image data may be processed as it is for printer output, so that it is not necessary to write to the memory MEM 65.
[0054]
First, when the memory MEM 65 is not used, the image processing ASIC 53 performs image reading correction on the read image data and then performs image quality processing for conversion into area gradation. The image data after the image quality processing is transferred to the VDC on the LD control board 92. With respect to the signal changed to the area gradation, post processing relating to dot arrangement and pulse control for reproducing the dots are performed by the VDC, and a reproduced image is formed on the transfer paper by the laser printer function.
[0055]
When data is stored in the memory MEM 65 and additional processing is performed at the time of reading from the memory MEM 65, for example, rotation in the image direction, image synthesis, or the like, the image data subjected to image reading correction is stored in the image controller access control function of the printer controller 60. Is sent to a peripheral ASIC 64. Here, the MPU 61 controls the image data and the memory module MEM65 according to the operation program stored in the flash EEPROM, and develops the print data for the external personal computer PC (character code / character bit conversion). , Compress / decompress image data for effective use of memory. The data sent to the peripheral ASIC 64 is stored in the MEM 65 after data compression, and the stored data is read out as necessary. The read data is expanded, returned to the original image data, and returned from the peripheral ASIC 64 to the image processing ASIC 53.
[0056]
When the image processing is returned to the ASIC 53, image quality processing is performed there, and pulse control with VDC on the LCD control board 92 is performed, and a visible image (toner image) is formed on the transfer paper by the laser printer function.
[0057]
The FAX transmission function, which is one of the composite functions, performs image reading correction on the read image data of the document scanner 10 by the image processing ASIC 53 and transfers it to the FAX control unit (FCU) 91. The FCU 91 performs data conversion to the public line communication network, and transmits it as FAX data to the communication network. In FAX reception, line data from the communication network is converted into image data by the FCU 91 and transferred to the image processing ASIC 53. In this case, no special image quality processing is performed, dot rearrangement and pulse control are performed in the VDC on the LCD control plate 92, and a visible image is formed on the transfer paper by the laser printer function.
[0058]
The MPU 51 of the main control board 50 controls the flow of image data, and the MPU 61 of the system controller 60 controls the entire system and manages the activation of each resource. The function selection of this digital multi-function copier is selected and input by the operation unit 20, and processing contents such as a copy function and a FAX function are set.
[0059]
The printer controller 60 is supplied with + 5VE, which is in the energized state even in the sleep mode. The main control plate 50 is supplied with + 5V that is deenergized in the sleep mode. The I / O control board 70 is supplied with + 5V and + 24V, respectively, which are similarly turned off in the sleep mode.
[0060]
The DC power source 80 is connected to switches 83 and 84 for + 24V and + 5VE (+ 5V voltage) of the converter output, respectively. A control signal for turning on / off the switches 83 and 84 is supplied from the printer controller 60 to the switches 83 and 84. When the printer controller 60 shifts to a sleep mode for energy saving, the switches 83 and 84 are turned off by this control signal.
[0061]
The target temperature of the fixing control 85 is set as the fixing operation temperature determined in the fixing process of the transfer paper to which the toner image is transferred, and the temperature of the fixing roller is maintained. The image is substantially delayed in response to the copy start or print command. The standby mode in which formation can be started, and the target temperature is set to 80% of the fixing operation temperature in order to reduce power consumption. In the low power mode in which the printer controller 60 can immediately perform the operation, the printer controller 60 turns on both the switches 83 and 84 by the control signal.
[0062]
In other words, in the sleep mode, the switches 83 and 84 are off, and the printer controller 60, the operation unit 20, the pressure plate opening / closing detection, and the minimum operation for detecting the action of the operator that indicates the possibility of using the copying machine or the print command of the personal computer PC. + 5VE is continuously applied to the electrical element or circuit. In the printer controller 60, + 5VE is continuously applied to a circuit that waits for the detection and turns on the switches 83 and 84 in response thereto and a memory that stores data that needs to be held in a nonvolatile manner.
[0063]
In the low power mode, the power is supplied to all of them, and only the set temperature of the fixing heater 123C is lowered.
[0064]
Analysis of the key-in data from the operation unit 20 and display control are controlled by the MPU 61 of the printer controller 60, and the interface with the operation unit 20 is handled by the peripheral ASIC 64. In this embodiment, the peripheral ASIC 64 and the operation unit 20 are connected via the mother board 90, the main control board 50, and the scanner control board 11. The printer controller 60 is connected to pressure plate opening / closing detection (not shown) via the mother board 90, the main control board 50 and the scanner control board 11 in the same manner as the operation unit 20.
[0065]
The pressure plate opening / closing detection is a detection switch that detects opening / closing of the ADF 30 when the ADF 30 is connected to the scanner, and a detection switch that detects opening / closing of the pressure plate for pressing the document when the ADF 30 is not attached. In any case, the pressure plate open / close detection generates a signal indicating whether the pressure plate for ADF or document pressing is in an open state, and this can be performed in any of the image processing operation state, the standby mode, the low power mode, and the sleep mode. The signal is given to the peripheral ASIC 64 of the printer controller 60 via the scanner control board 10, the main control board 50, and the motherboard 90, and the MPU 61 reads this signal. A power supply (+ 5VE) for representing a signal indicating whether or not it is in an open state and a power supply (+ 5VE) for detecting the ON of the input key of the operation unit 20 and generating a detection signal are the motherboard 90, the main control board 50, and the scanner. The process controller 60 applies the open / close detection switch and the operation unit 20 via the control board 10.
[0066]
If the ADF 30 is installed, it is connected to the scanner control board 11. A detection signal of a document sensor for detecting whether or not there is a document on the document table of the ADF 30 is also given to the peripheral ASIC 64 of the printer controller 60 via the scanner control board 10, the main control board 50, and the motherboard 90, and the MPU 61 receives this signal. Read. A power supply (+ 5VE) for the document sensor to generate a detection signal indicating the presence or absence of the document is also supplied from the process controller 60 to the document sensor via the mother board 90, the main control board 50, and the scanner control board 10.
[0067]
Dual electrical relays with two sets of contacts on each of the + 24V power supply line and the + 5V power supply line between the SW 83 and 84 of the DC power supply / AC control board 80 and the I / O control board 70 to which many electrical loads are connected. 86 sets of contacts are inserted. The + 24V power supply line is opened and closed by the relay contact a, and the + 5V power supply line is opened and closed by the relay contact b. The output voltage +24 V of SW83 is applied to the electric coil of the relay 86 through the door switch 73. The fixing energization circuit 85 for supplying commercial AC to the fixing heater 123C has an electric relay (not shown) inserted in the commercial AC voltage line. The electric coil of this electric relay also has an output voltage + 24V of SW83 through the door switch 73. Is applied.
[0068]
The door switch 73 is an interlock switch that is turned off by opening the front door of the printer 100 and turned on by closing. In addition to the front door, when the electric relay of the DC power supply / AC control plate 80 is opened also by opening the side door or the cover, a switch that is opened and closed by opening or closing the door or cover is referred to as a door switch. 73 and each electrical relay are inserted in series.
[0069]
FIG. 5 shows a circuit configuration for detecting the open delay of the contacts a and b of the electric relay 86 in the interlock circuit including the door switch 73 and the electric relay 86 on the electric circuit system shown in FIG. The interlock circuit includes a door switch 73, an electric relay 86, and an MPU 51 on the main control board 50.
[0070]
When the front cover of the printer 100 is opened, the door switch 73 is turned OFF, and the supply of + 24V to the electric coils of the electric relay 86 and the electric relay (not shown) in the fixing energizing circuit 85 is cut off. Accordingly, the contacts a and b of the relay 86 are opened, and the supply of + 24V and + 5V to the load is cut off.
[0071]
The load 85 is an electric relay (not shown) in the fixing energization circuit 85. The loads 5 and 6 are a 24V load and a 5V load that are permanently installed in the printer 100, respectively. Each of the loads 7 and 8 is connected to the printer 100 as an option, and the contacts a and b of the relay 86 are connected from the first power circuit of + 24V output and the second power circuit of + 5V output on the DC power / AC control board 80. The power is supplied via
[0072]
+ 24V that is turned OFF / ON by the door switch 73, + 24V that is turned OFF / ON by the contact piece a of the relay 86, and + 5V that is turned OFF / ON by the contact piece b are respectively supplied to the interrupt ports INT0, INT1, and INT2 of the MPU 51 as interrupt signals. Entered. In this embodiment, the interrupt port INT0 is at a high potential H when the door switch 73 is closed, and is at a low potential L when it is opened. The interrupt port INT1 is at a high potential H when the contact piece a of the relay 86 is closed, and is at a low potential L when it is open. The interrupt port INT2 is at a high potential H when the contact b of the relay 86 is closed, and is at a low potential L when it is open.
[0073]
Information to be notified to the user and the service person is displayed on the display panel of the operation unit 20 by the MPU 61 via the MPU 51 or the MPU 51.
[0074]
When the MPU 51 is set to a mode other than the above-described sleep mode for energy saving (the above-described standby mode, low power mode, and image processing operation mode), any of the power supply to the loads 5 to 6 is turned on from off. When switching to or vice versa, a reference value corresponding to the power supply load is set.
[0075]
FIG. 6 shows the setting contents of the reference value. Here, the MPU 51 first corresponds to the combination of ON and OFF of the loads 5 and 7, and when both the loads 5 and 7 are OFF, the reference value T1s is set to the relay contact piece a at the time of + 24V system no load. A switching delay reference value t10 from closed to open is set. When only the load 5 is turned on, the delay reference value t11 is set to the reference value T1s. When only the load 7 is turned on, the delay reference value t12 is set. When both the loads 5 and 7 are turned on, the delay reference value t13 is set to the reference value T1s. Set (steps 1-7). In the following, the word “step” is abbreviated in parentheses, and step no. Write numbers only.
[0076]
Here, the reference value t10 is obtained when the voltage to the electric coil of the relay 86 is cut off by switching the door switch 73, which is an interlock switch, from closed to open, and then when the + 24V system contact a is unloaded. The reference value t11 is a value obtained by adding an allowable error to the specification value of the switching delay time from closing to opening, and the reference value t11 is the switching delay time from closing to opening of the contact a when power is supplied only to the load 5. A value obtained by adding an allowable error to the specification value, the reference value t12 is the same value when power is supplied only to the load 7, and the reference value t13 is the same value when power is supplied to the loads 5 and 7. It is.
[0077]
Next, when both of the loads 6 and 8 are turned off corresponding to the combination of on and off of the loads 6 and 8, the MPU 51 closes the relay contact b when the + 5V system is not loaded to the reference value T2s. The delay reference value t20 for switching from to open is set. The delay reference value t21 is set to the reference value T2s when only the load 6 is turned on, the delay reference value t22 is turned on when only the load 8 is turned on, and the delay reference value t23 is turned on when both the loads 6 and 8 are turned on. Set (8-14).
[0078]
Here, the reference value t20 is changed from the closed state of the + 5V system contact b to the open state after the voltage to the electric coil of the relay 86 is cut off by switching the door switch 73 from the closed state to the open state. The reference value t21 is a value obtained by adding an allowable error to the specification value of the switching delay time, and the reference value t21 is an allowable error in the specification value of the switching delay time from closing to opening of the contact piece b when only the load 6 is fed. The reference value t22 is the same value when only the load 8 is fed, and the reference value t23 is the same value when the loads 6 and 8 are fed.
[0079]
FIG. 7 shows the contents of the INT0 interrupt CAM1 in response to the fall of the potential of the interrupt port INT0 from H to L (change from the closing of the door switch 73 to the opening) of the MPU 51. When the operator opens the front door of the printer 100, the door switch 73 changes from closed to open, and when the potential of the interrupt port INT0 falls from H to L, the MPU 51 causes the potential of the interrupt port INT0 to be H. In response to the fall from L to L, the process proceeds to the INT0 interrupt CAM1, and each time count using the time counters T0, T1 and T2 is started (21). Next, the MPU 51 waits for the interrupt port INT1 or INT2 to fall to the low level L (22, 23, 24, 29). While waiting, it is checked whether the time measured value T0 using the time counter T0 is equal to or greater than the threshold value tw for determining the open movement abnormality of the contact pieces a and b (34).
[0080]
When T0 becomes equal to or greater than tw, the MPU 51 turns on the timer flag 0 (35). That is, information indicating an abnormal opening movement of the relay 86 is written in the memory. Next, the MPU 51 resets the time counters T0, T1, and T2 (36), and displays an abnormal opening movement of the electric relay 86 on the display panel of the operation unit 20 (37, 40).
[0081]
If the interrupt port INT1 is switched from H to L before T0 becomes equal to or greater than tw, the MPU 51 stops the time T1 using the time counter T1 (25), and the time T1 is used to determine the opening delay of the contact piece a. Whether the reference value T1s is equal to or greater than the reference value T1s (26). That is, information indicating the delay in opening the contact piece a of the relay 86 is written in the memory. Next, the MPU 51 checks whether or not the detection of the contact piece b has been completed (28). If completed, the MPU 51 resets the time counters T0, T1 and T2 (36), and displays on the operation unit 20. Information representing the delay in opening the contact piece a of the electrical relay 86 is displayed on the panel (38, 41).
[0082]
In addition, if the interrupt port INT2 switches from H to L before T0 becomes tw or more, the MPU 51 stops the time T2 using the time counter T2 (30), and the time T2 is released from the contact b. It is checked whether or not the reference value T2s for delay determination is greater than or equal to 31 (31). That is, information indicating the delay in opening the contact b of the relay 86 is written in the memory. Next, the MPU 51 checks whether the detection of the contact piece a has been completed (33). If completed, the MPU 51 resets the time counters T0, T1, and T2 (36), and displays on the operation unit 20. Information representing the delay in opening the contact b of the electric relay 86 is displayed on the panel (39, 42).
[0083]
In the first embodiment, as described above, each delay time from the change to opening of the door switch 73 to the opening of the relay contact pieces a and b (output OFF) is measured. Further, with this configuration, not only the OFF timing but also the status of each output can be monitored. It is also possible to detect abnormalities such as contact anomalies caused by contamination of silicon oil and other impurities, and short circuit failures such as circuit shorts.
[0084]
-Second Example-
The hardware of the second embodiment is the same as that of the first embodiment described above. Further, the contents of “reference value setting” performed by the MPU 51 of the second embodiment are also the same as the contents of “reference value setting” RDP shown in FIG. However, the MPU 51 of the second embodiment also detects the reversal of the order of the opening delays of the + 24V contact a and the + 5V contact b in addition to the contents of the “INT0 interrupt” CAM1 shown in FIG. 7 of the first embodiment. When the operation of the relay 86 is healthy, the + 5V system contact b is opened first, and then the + 24V system contact a is opened. The reverse of this order may be the progress of contact transfer of the + 5V system contact b, contact welding, or some load circuit abnormality.
[0085]
FIG. 8 shows the contents of the “INT0 interrupt” CAM2 of the MPU 51 of the second embodiment. Here, in response to the door switch 73 changing from closed to open and the potential of the interrupt port INT0 falling from H to L, the MPU 51 starts each time count using the time counters T0, T1 and T2. After (21), when the interrupt port INT2 is switched from H to L, the MPU 51 stops the timing T2 using the time counter T2. At this time, the MPU 51 checks whether the detection of opening of the contact piece a is completed. (33) When completed, since the contact piece a is not yet opened, the timer flag 3 is turned ON on the assumption that the order of the opening delays of the + 24V contact point a and the + 5V contact point b is reversed. (43). That is, information indicating the malfunction of the relay 86 and the opening delay of the contact piece b is written in the memory. Then, the time counters T0, T1, and T2 are reset (36), and information representing the malfunction of the relay 86 and the delay in opening the contact piece b is displayed on the display panel of the operation unit 20 (37, 44). Other functions of the second embodiment are the same as those of the first embodiment.
[0086]
-Third Example-
FIG. 9 shows an interlock circuit of the third embodiment and a closing delay detection circuit of the electric relay 86. This closed delay detection circuit is connected to the interrupt ports INT0, INT1 and INT2 of the MPU 51 of the open delay detection circuit common to the first and second embodiments shown in FIG. 57 is inserted. Since the switch signal given to the interrupt ports INT0, INT1 and INT2 of the MPU 51 is an inversion of the switch signal of the first embodiment, the MPU 51 of the third embodiment has the door switch 73 switched from OFF to ON. Sometimes an INT0 interrupt is executed.
[0087]
FIG. 10 shows the contents of the reference value setting by the MPU 51 of the third embodiment. In this third embodiment, when the door switch 73 is switched from OFF to ON, the relay 86 is turned OFF by the OFF of the door switch 73 in the immediately preceding state, and all of the loads 85 and 5 to 8 are supplied from the power source. Blocked. When the door switch 73 is switched from ON to OFF, the MPU 51 does not drive (deenergize) the control signal to the loads 5 to 8, so that when the door switch 73 is switched from OFF to ON, all The load does not return to the energized state of the ON state immediately before the door switch 73 is turned off at the same time. However, each of the loads 5 to 8 has a power-on reset circuit that generates a reset pulse when an operating voltage is applied, and there is a circuit or a controller that performs an initialization operation in response to the reset pulse. When 73 is switched from OFF to ON and relay 86 is switched from OFF to ON, depending on whether or not optional loads 7 and 8 are connected to the + 24V system and + 5V system power supply lines, the current flows to each power supply line. When the inrush current values are different and the loads 7 and 8 are connected, the closing (on) delay time of the relay contacts a and b in appearance (rising of the energized current value) is shortened.
[0088]
Accordingly, the MPU 51 of the third embodiment first sets the delay reference value t10c to the reference value T1s when there is no connection of the load 7 (51), in response to whether or not the load 7 is connected (addition) (52). When the load 7 is connected, the delay reference value t11c is set (53). Corresponding to whether there is connection (addition) of the load 8 (54), when there is no connection of the load 8, the reference value T2s is set to the delay reference value t20c (55), and when there is connection of the load 8, it is delayed. A reference value t21c is set (56).
[0089]
Here, the reference value t10c is the value when the load 24 is not connected to the + 24V system contact piece a after the voltage is applied to the electric coil of the relay 86 by switching the door switch 73 from opening to closing. The reference value t11c is a value obtained by adding an allowable error to the specification value of the switching delay time from to open, and the reference value t11c is the specification value of the switching delay time from opening to closing of the + 24V system contact a when the load 7 is connected. It is a value with an allowable error added. The reference value t20c is changed from opening to closing when the load 8 of the + 5V system contact b is not connected after the voltage is applied to the electric coil of the relay 86 by switching the door switch 73 from opening to closing. The reference value t21c is a value obtained by adding an allowable error to the specification value of the switching delay time, and the reference value t21c indicates an allowable error in the specification value of the switching delay time from opening to closing of the + 5V system contact b when the load 8 is connected. It is the added value. Note that t11c <t10c, t21c <t20c, and T1s <T2s.
[0090]
FIG. 11 shows the contents of the “INT0 interrupt” CAM2c of the MPU 51 of the third embodiment. Here, in response to the door switch 73 changing from open to closed and the potential of the interrupt port INT0 falling from H to L, the MPU 51 starts each time count using the time counters T0, T1 and T2. After (c21), when the interrupt port INT1 is switched from H to L, the MPU 51 stops the timing T1 using the time counter T1, and at this time, checks whether or not the detection of the contact b has been completed. (C28), if completed, the contact piece b has not yet been opened, so that the timer flag 3 is turned ON on the assumption that the order of the opening delays of the + 24V contact point a and the + 5V contact point b has been reversed. (C43). That is, information indicating the malfunction of the relay 86 and the opening delay of the contact piece a is written in the memory. Then, the time counters T0, T1, and T2 are reset (c36), and information indicating the malfunction of the relay 86 and the opening delay of the contact piece a is displayed on the display panel of the operation unit 20 (c37, c44). Other hardware and functions of the third embodiment are the same as those of the first embodiment.
[0091]
-Fourth embodiment-
In the fourth embodiment, as in the case of the INT0 interrupt shown in FIG. 7, the step c43 for detecting the reverse of the order of the open delays and the step c44 for displaying the result in FIG. 11 are deleted. The wear is the same as in the third embodiment.
[0092]
【The invention's effect】
The contact transfer status of the interlock switch means (86) inserted in the power supply line from the power source to the load can be grasped more accurately.
[Brief description of the drawings]
FIG. 1 is a plan view showing an external appearance of a digital copying machine equipped with a power supply apparatus according to a first embodiment of the present invention.
FIG. 2 is a longitudinal sectional view showing an outline of the mechanism of the color printer 100 shown in FIG.
3 is a block diagram showing a system configuration of an electric system of the digital copying machine shown in FIG.
4 is a block diagram showing an outline of a configuration of a DC power supply 80 shown in FIG. 3. FIG.
5 is an electric circuit diagram showing a circuit configuration for detecting an open delay of contacts a and b of an electric relay 86 in an interlock circuit including a door switch 73 and an electric relay 86 on the electric circuit shown in FIG. is there.
6 is a flowchart showing the contents of a “reference value setting” RDP of the MPU 51 shown in FIG. 4. FIG.
7 is a flowchart showing the contents of interrupt processing of the MPU 51 shown in FIG.
FIG. 8 is a flowchart showing the contents of interrupt processing of an MPU 51 according to the second embodiment of the present invention.
FIG. 9 is an electric circuit diagram showing a circuit configuration for detecting the closing delay of the contacts a and b of the electric relay 86 used in the third embodiment of the present invention.
FIG. 10 is a flowchart showing the contents of “reference value setting” RDPc of the MPU 51 of the third embodiment.
FIG. 11 is a flowchart showing the contents of interrupt processing of an MPU 51 according to the third embodiment of the present invention.
[Explanation of symbols]
100: Color printer
73: Door switch
86: Electric relay
a, b: contact piece
5, 56, 57: Inverter

Claims (6)

Inserted from the power supply to the power supply line to the load, energized individually to a plurality of power supply lines in response to the supply of one of the closing command signal, the supply of the closed instruction signal to cut off individually energized and you stop dual switching means; and, interrupting means for interrupting the supply of closing command signal to the dual switch means; in the power supply device having an interlock circuit comprising,
Reference value setting means for setting each reference value corresponding to each load amount connected to each power supply line connected to the power supply via the duplex switch means;
Delay detection means for detecting said from the start of supply of the closing command signal to the dual switch means, the delay of each energization of the respective power supply line by said double switching means in response thereto; and
Informing means for informing corresponding to the length of the detected delay with respect to the reference value;
A power supply apparatus having an interlock circuit. Inserted from the power supply to the power supply line to the load, energized individually to a plurality of power supply lines in response to the supply of one of the closing command signal, the supply of the closed instruction signal to cut off individually energized and you stop dual switching means; and, interrupting means for interrupting the supply of closing command signal to the dual switch means; in the power supply device having an interlock circuit comprising,
Reference value setting means for setting each reference value corresponding to each load amount connected to each power supply line connected to the power supply via the duplex switch means;
Delay detection means for detecting said from the stop of the supply of the closing command signal to the dual switch means, the delay of the stop of the energization of the respective power supply line by said double switching means in response thereto; and
Informing means for informing corresponding to the length of the detected delay with respect to the reference value;
A power supply apparatus having an interlock circuit. The power supply device according to claim 1 or 2 , wherein the notification unit performs notification associated with the change when the order between delays of each power supply line is changed. The blocking means is an electrical switch having a from the open to the closed or OFF switched electrical contact piece in the opposite through Setsu換Ri to non-working from the action of external forces, inter according to any one of claims 1 to 3 A power feeding device having a lock circuit. Image formation in which an electrostatic latent image is formed on a photoconductor, the electrostatic latent image is visualized as a toner image by a developing device, and the toner image is transferred directly or indirectly to a transfer sheet via an intermediate medium In the device
A plurality of power supply lines in the device, an image forming apparatus characterized by being equipped with a feeding device according to any one of claims 1 to 4. The apparatus further document scanner for generating the read image data by reading an image of a document; and, the read image data, said means for processing the image data for forming an electrostatic latent image on the photosensitive member; comprises, The image forming apparatus according to claim 5.

Images