JP2012150254A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus that includes a cooling device employing a liquid cooling system that, in the case of a liquid spill that is not likely to cause serious failure, suppresses a liquid spill and maintains the cooling capacity of the device to allow the operation of the image forming apparatus to be continued, while preventing the occurrence of serious failure; and that includes a cooling device employing a liquid cooling system that allows the operation of the image forming apparatus to be continued for a long period, rather than a liquid cooling system that is configured not to regulate the flow rate of cooling liquid in the cooling device, when the operation of the image forming apparatus is continued.SOLUTION: Each unit in a cooling liquid circulation passage of a cooling device 10 is connected with a pipe 4 by a rubber tube 410, and a spilled liquid receiving tray 420 and a liquid amount detection sensor 421 are provided below each of the connections. The flow rate of a pump 1 is controlled based on the total amount of spilled liquid detected by the liquid amount detection sensor 421.

Description

  The present invention relates to an image forming apparatus including a cooling device that efficiently cools a heat generation portion of a cooling target by circulating a cooling liquid in a cooling liquid circulation path.

  An image forming apparatus such as a printer, a facsimile machine, a copying machine, or a multifunction machine records images such as characters and symbols on a recording medium such as paper or an OHP sheet based on image information. There are various types of such image forming apparatuses. Conventionally, the electrophotographic method has been widely used because it can record high-definition images on plain paper at high speed.

  FIG. 12 is a schematic configuration diagram of a color copying machine which is an example of a conventional general electrophotographic image forming apparatus. In a color copier, image information is read by an optical device 300 such as a scanner, and light for writing an electrostatic latent image on the four photosensitive drums 40 of the image forming unit 100 is written according to the image information. 31 is irradiated. In the image forming unit 100, toners in the developer are deposited on the photosensitive drums 40Y, C, M, and Bk by the yellow, cyan, magenta, and black developing devices 70Y, C, M, and Bk to form toner images. Then, the image is sequentially transferred to the intermediate transfer belt 15. Then, the toner image on the intermediate transfer belt 15 is further transferred to the recording medium P by the secondary transfer device 19. In the fixing device 60, the toner on the recording medium P is melted and fixed to the recording medium P by heating and pressurizing the recording medium P to which the toner image is transferred. Thereafter, when recording on only one side of the recording medium P, the recording medium P is discharged to the paper discharge tray 57. When recording on both sides of the recording medium P, the front and back sides of the recording medium are reversed in the duplex unit 28 and conveyed again upstream, and the above-described process is performed again.

  The above image forming process involves heat generation and temperature rise. For example, in the optical apparatus 300, a scanner lamp that scans a document and a scanner motor that drives the scanner lamp generate heat, and in the writing apparatus 31, a motor that drives a polygon mirror that rotates at high speed generates heat. Further, in the developing device 70, the temperature rises due to frictional heat due to the stirring of the toner and the developer when the toner is charged, and in the fixing device 60, the temperature of the peripheral portion is increased due to the heat of the heater for heat fixing. The recording medium P after fixing becomes high temperature. For this reason, the temperature of the double-sided unit 28 that is the subsequent transport path is increased.

  These heats stay in the main body of the color copying machine, causing various harmful effects. For example, when the temperature of the toner is raised to about the softening point, image quality failure occurs, or a moving part such as a drum unit, the developing device 70, or a toner container (not shown) is locked and a failure occurs. Further, the oil such as the bearing deteriorates due to the rise in temperature, and the mechanical life of the motor is shortened. Or, if the heat radiation of the IC on the electric board is insufficient, it may cause malfunction or failure. Furthermore, deformation may occur in a resin component having a low heat-resistant temperature. Conventionally, in order not to cause these problems, cooling of a heat generating portion has been performed by an air cooling method using a cooling fan and a duct.

  However, recent image forming apparatuses have been required to be efficiently cooled because the amount of heat generated by each apparatus such as an optical apparatus, a developing apparatus, and a fixing apparatus has been increased as the speed has been increased, and the miniaturization has progressed. Each device is mounted in the main body at high density. For this reason, there is no room for space around each device. And it is difficult to secure a space for installing a duct for conveying the airflow of the cooling fan around each device, and it is difficult to forcibly cool each device.

  Therefore, instead of the conventional air cooling method using a cooling fan, a liquid cooling method has been devised in which a more efficient cooling effect can be obtained even when there is little space around each device. In the liquid cooling method, a flow path of the coolant is formed at the heat generation point, or the heat receiving portion that forms the flow path is brought into close contact with or in close proximity, and the coolant is supplied to the flow path at a lower temperature than the heat generation point. It takes heat away. In general, the coolant is mainly composed of water, and propylene glycol or ethylene glycol is added to lower the freezing temperature of the coolant.

  FIG. 13 is an explanatory diagram of a configuration of a conventional general liquid cooling type cooling apparatus. In this liquid cooling type cooling device, a heat receiving portion 2, a tank 3, a pump 1, and a heat radiating portion 5 that are in close contact with the side surface of each developing device 70 are connected via a cooling liquid pipe 4. Consists of configuration. The cooling liquid warmed in the heat receiving unit 2 is cooled by the heat radiating unit 5 so that a predetermined amount of the cooling liquid is circulated to perform cooling. The heat radiating portion 5 includes a flow path formed of a good heat conductive member and a radiator 5a formed of a good heat conductive member connected to the flow path. And the flow path and the radiator 5a are cooled by forced convection heat transfer using the cooling fan 5b, and the temperature of the coolant flowing in the flow path is lowered.

  As described above, a metal such as copper or aluminum is used for the heat receiving portion 2 or the heat radiating portion 5 of the cooling device, and a metal pipe or a rubber tube is used for the pipe 4. Further, in order to prevent corrosion of metal components, the coolant is often used after adding a rust inhibitor (for example, phosphate-based material: potassium phosphate, inorganic potassium salt, etc.). However, depending on the usage environment and storage environment (for example, high temperature and humidity), the rubber tube may crack or come out of the joint part of the metal component to which the rubber tube is connected. There was a risk of leaking into the device. If the coolant leaks from the pipeline 4, the leaked coolant not only contaminates the image forming apparatus, but also causes serious problems such as a short circuit caused by touching an electrical circuit or high voltage part that requires insulation. May occur.

  On the other hand, image forming apparatuses that require a countermeasure against heat as described above are often used in a so-called production printing area that requires high-speed output. The area of production printing includes, for example, the area of Data Center indicating a business output center that specializes in output of invoices and financial statements in a large company or the like. In addition, the Transpromo area targeted for printing and direct mail (DM) companies, and the In Plant area used for printing applications such as manuals, in-house educational materials, and business cards at in-house copy centers. Also mentioned. In addition, areas such as copy shops, supermarkets, and convenience stores such as PFP (Print for Pay), which are used for printing simple catalogs and promotional materials, or presentation materials, for example, are also included. Stopping an image forming apparatus used in such an area directly leads to a user's main business stoppage and a decrease in sales. Therefore, it is desirable to shorten as much as possible the time during which the image forming apparatus is stopped between the occurrence of a trouble and the repair or maintenance (hereinafter referred to as a downtime before repair). Even when a liquid leak occurs in such an image forming apparatus, it is necessary to quickly detect the liquid leak and prevent a serious malfunction.

  Therefore, in an image forming apparatus in the production printing area, a liquid leakage from a flow path of a coolant is detected to prevent a serious malfunction and shorten downtime before repairing the image forming apparatus. Various configurations have been proposed. For example, in the configuration described in Patent Document 1, each of the joint portions of the inlet side pipe, the outlet side pipe provided in the heat receiving portion, and the tube connected to each of them is electrically connected to the image forming portion to perform drive control and the like. It arrange | positions in the space formed of the shielding member between the parts. And the liquid leak detection sensor is provided in the joint part vicinity of each piping and each tube of a heat receiving part. Since each joint portion is arranged in a space formed by the shielding member, the leaked cooling liquid is blocked by the shielding member when liquid leakage occurs in each joint portion, and the leaked cooling liquid is blocked by the image forming portion. In addition, it is possible to prevent the drive electrical component from being immersed. And since the liquid leak detection sensor is provided in the vicinity of each joint part, when the liquid leak occurs in each joint part, the liquid leak can be detected.

  However, in the configuration of Patent Document 1, it is possible to detect the leakage of the coolant at each joint portion, but it is impossible to determine how serious the detected leakage can cause a malfunction. For this reason, even when there is a liquid leak that does not require immediate repairs or maintenance, the image forming apparatus must be stopped when a liquid leak is detected, and a downtime before repair occurs, causing the image forming apparatus to operate. I can't continue. In other words, even in the case of a liquid leak that is unlikely to cause a serious malfunction, if the liquid leak is detected, the image forming apparatus must be stopped, and a downtime before repair occurs, resulting in an image forming apparatus. Cannot continue to operate. Therefore, the inventors examined the following configuration.

  Reduced liquid amount detecting means for detecting the reduced liquid amount of the cooling liquid in the cooling device, leaking liquid trays disposed at a plurality of locations where liquid leakage may occur in the cooling device, and the leaking liquid tray Leakage liquid amount detection means for detecting the received coolant amount is provided. When a liquid leak occurs, whether or not the liquid leak causes a serious malfunction is determined based on the reduced liquid volume detected by the reduced liquid volume detector and the total leaked liquid volume detected by the leaked liquid volume detector. to decide. That is, the seriousness of the malfunction due to liquid leakage is determined. Specifically, the seriousness of the failure is determined based on conditions such as one or a plurality of threshold values set in advance for each liquid leakage amount and the liquid leakage amount per unit time. In the judgment of the seriousness of the malfunction due to the liquid leakage, if it is determined that the liquid leakage does not cause a serious malfunction, the judgment of the seriousness of the malfunction due to the liquid leakage is continued to prevent a serious malfunction. The operation of the image forming apparatus is continued. Then, based on the reduced liquid volume detected by the reduced liquid volume detector and the total leaked liquid volume detected by the leaked liquid volume detector, the severity of the malfunction due to the liquid leakage is determined, so that the liquid is detected at the assumed location. It can also be determined whether or not a leak has occurred.

  However, the configuration studied by the inventors is a configuration in which the cooling device is operated without adjusting the flow rate of the cooling liquid in the cooling device when it is determined that the liquid leakage does not cause a serious problem. By operating the cooling system without adjusting the flow rate of the cooling liquid in the cooling system, the amount of liquid leakage at the liquid leakage location increases due to the pressure of the cooling liquid, and the cooling performance of the cooling system decreases accordingly. There is a possibility. For these reasons, there is a problem that even if the operation of the image forming apparatus is continued while preventing a serious failure, the operation of the image forming apparatus may be continued only for a short time.

  The configuration studied by the inventors is also provided with a decrease liquid amount detection means in addition to the leakage liquid amount detection means, and is also described in Patent Document 1 in that it can be determined whether or not a liquid leak has occurred at an assumed location. Better than the configuration. However, it is considered possible to configure the cooling device so as to limit the location where liquid leakage occurs under normal use environment to the assumed location. The reason for this is as follows. The main causes of liquid leakage are material deterioration of each part of the cooling device and damage due to deformation when external force is applied. For this reason, if it is under normal use environment, if the selection of the material of each part, processing, and the setting of the joint position etc. which connect each part are performed appropriately, a liquid leak location may be limited to the joint part which connects each part. This is because it can. Therefore, under the normal usage environment, if the location of the leaked liquid amount detection means is properly specified and the cooling device is properly configured, the leaked liquid quantity detection means alone can determine the seriousness of the malfunction due to liquid leakage. It is thought that this can be done appropriately. Here, the normal use environment is intended to be a general use environment excluding an environment of excessively high temperature and humidity, an excessively inclined installation position, an environment subject to excessive vibration and impact, and the like.

  However, it can be limited to places where liquid leakage occurs under normal operating environment, and without providing a reduced liquid volume detection means, the seriousness of the malfunction is based on the total leakage liquid volume detected by the leakage liquid volume detection means. Even if it changes to the structure which judges property, it does not change that it operates a cooling device, without adjusting the flow volume of the cooling fluid in a cooling device. For this reason, even if the seriousness of the failure is determined based on the total leakage amount detected by the leakage amount detection means, even if the operation of the image forming apparatus is continued while preventing a serious failure. There is a problem that the operation of the image forming apparatus may be continued only for a short time.

  The present invention has been made in view of the above problems, and an object thereof is to provide the following image forming apparatus. In the case of a liquid leak that has a low possibility of causing a serious malfunction, an image having a liquid cooling type cooling device that can prevent the serious malfunction from occurring and suppress the liquid leakage while continuing the operation of the image forming apparatus. Forming device. When the operation of the image forming apparatus is continued, the image forming apparatus includes a liquid cooling type cooling device that can continue the operation of the image forming apparatus for a longer time than the configuration in which the flow rate of the cooling liquid in the cooling device is not adjusted.

In order to achieve the above object, the invention according to claim 1 is an image forming apparatus provided with a cooling device for cooling a temperature rising portion by circulating a cooling liquid in a cooling liquid circulation path. A heat receiving portion that is close to or in contact with the temperature rising portion, a heat radiating portion that dissipates heat removed from the temperature rising portion by the heat receiving portion to the outside of the image forming apparatus, and a storage portion that stores the cooling liquid, A liquid feed section for moving the coolant in the coolant circulation path, and a pipe section communicating so that the coolant can circulate between the heat receiving section, the heat radiating section, the storage section, and the liquid feed section. The cooling device has a leakage amount detecting means for detecting the leakage amount of the cooling liquid from the cooling liquid circulation path, and based on the leakage amount detected by the leakage amount detection means, It is characterized by having a liquid feeding unit control means for controlling the flow rate of the cooling liquid in the cooling device. Is shall.
According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, the flow rate of the coolant in the cooling device is controlled based on the leaked liquid amount per unit time detected by the leaked liquid amount detecting means. The liquid-feeding part control means is provided.
According to a third aspect of the present invention, in the image forming apparatus according to the first or second aspect,
The heat dissipating unit includes a radiator having a coolant flow path and a cooling fan that blows air to the radiator, and controls the number of rotations of the cooling fan based on the flow rate of the coolant in the cooling device. A fan control means is provided.
According to a fourth aspect of the present invention, in the image forming apparatus according to any one of the first to third aspects, the number of sheets to be imaged per unit time is determined based on a flow rate of the cooling liquid in the cooling apparatus. The number-of-sheets control means to control is provided.
According to a fifth aspect of the present invention, in the image forming apparatus according to any one of the first to fourth aspects, the continuous sheet passing time control unit controls the continuous sheet passing time based on the flow rate of the cooling liquid in the cooling apparatus. It is characterized by having.
Since the present invention is provided with the leakage amount detecting means for detecting the leakage amount of the cooling liquid from the cooling liquid circulation path, it is determined whether or not the leakage has occurred based on the detected leakage amount of the cooling liquid. it can. This is because, when a liquid leak occurs, the coolant flows out from the cooling device, and the leaked liquid amount detected by the leaked liquid amount detection means is larger than 0, and it is determined that the liquid leak has occurred. This is because it can.
When a liquid leak occurs, it can be determined whether or not the liquid leak causes a serious problem that requires immediate repair or maintenance based on the detected amount of the leaked liquid. That is, when the detected amount of leaked liquid is less than a predetermined value, it can be determined that the liquid leak does not cause a serious problem. If the determination is made in this way, the image forming apparatus can be operated while preventing serious problems from occurring by controlling the operation of the image forming apparatus to continue.
Further, when it is determined that the liquid leakage does not cause a serious malfunction based on the detected amount of leaked liquid, the flow rate of the liquid feeding unit is controlled by the liquid feeding unit control means. With this control, it is possible to reduce the pressure of the coolant in the coolant circulation path so as to decrease the flow rate of the fluid feed unit as the detected amount of leaked fluid increases. As the amount of leaked liquid detected in this way increases, the flow rate by the liquid feeding unit is reduced and the pressure of the cooling liquid in the cooling liquid circulation path is reduced, so that liquid leakage can be suppressed. The cooling performance can be maintained for a longer time compared to a configuration that does not reduce the flow rate of the feeding section. Therefore, when the operation of the image forming apparatus is continued with a liquid leak that is unlikely to cause a serious malfunction, the image is longer than the conventional configuration in which the flow rate of the liquid feeding unit is not adjusted while suppressing the liquid leakage. The operation of the forming apparatus can be continued.

  According to the present invention, in the case of a liquid leak that is unlikely to cause a serious malfunction, it is possible to continue the operation of the image forming apparatus while continuing to determine the seriousness of the malfunction due to the liquid leak. Then, by controlling the flow rate of the liquid feeding unit of the cooling device based on the detected amount of leaked liquid, the image is longer than the conventional configuration in which the flow rate of the liquid feeding unit is not adjusted while suppressing liquid leakage. The operation of the forming apparatus can be continued. Therefore, in the case of a liquid leak that is unlikely to cause a serious malfunction, a liquid cooling type cooling device that can continue the operation of the image forming apparatus while preventing the serious malfunction and suppressing the liquid leakage. An image forming apparatus can be provided. When the operation of the image forming apparatus is continued, an image forming apparatus including a liquid cooling type cooling device that can continue the operation of the image forming apparatus for a longer time than the configuration in which the flow rate of the cooling liquid in the cooling device is not adjusted can be provided. .

1 is an overall schematic diagram of a copier according to an embodiment. 1 is a schematic configuration diagram of a cooling device according to Embodiment 1. FIG. The table | surface which shows the control target of a pump flow rate based on the total liquid leak amount detected with each liquid amount detection sensor which concerns on Example 1. FIG. The table | surface which shows the control target of a pump flow rate based on the total leaked liquid amount detected with each liquid quantity detection sensor which concerns on Example 2, and the total leaked liquid amount per unit time. FIG. 6 is a schematic configuration diagram of a cooling device according to a third embodiment. FIG. 6 is a control flow diagram of pump flow rate and fan rotation speed based on the total leakage amount detected by each fluid amount detection sensor according to Example 3 and the total leakage amount per unit time. The table | surface which shows the number of sheets per unit time based on the total leaked liquid amount detected with each liquid quantity detection sensor which concerns on Example 4, and the pump flow volume derived | led-out from the total leaked liquid amount. The table | surface which shows the control target of a pump flow rate, and the continuous paper passing time based on the total leaked liquid amount detected with each liquid quantity detection sensor which concerns on Example 5, and the total leaked liquid amount per unit time. FIG. 10 is a control flow diagram of a pump flow rate and a continuous sheet passing time based on a total leakage amount detected by each liquid amount detection sensor according to Example 5 and a total leakage amount per unit time. The figure which showed the time change of the developer temperature in the color where a developer temperature becomes the highest when a pump flow rate is a normal flow rate and there is no restriction | limiting in continuous paper passage time. The figure which showed the time change of the developer temperature in the color where the developer temperature becomes the highest when the pump flow rate is 70% of the flow rate and the continuous paper passing time is 5 hours. 1 is a schematic configuration diagram of a color copying machine as an example of a conventional general electrophotographic image forming apparatus. Structure explanatory drawing of the conventional general liquid cooling type cooling device.

  Hereinafter, an embodiment of a color laser copying machine (hereinafter simply referred to as “copying machine”) which is an electrophotographic image forming apparatus will be described with reference to the drawings. FIG. 1 is an overall schematic diagram of a copying machine according to the present embodiment. First, an outline of a copying machine that is an image forming apparatus of the present embodiment common to each example will be described.

  This copying machine is a copying machine main body and is mainly composed of an image forming unit 100 for forming an image, a paper feed table 200 on which the image forming unit 100 is placed, and a scanner 300 mounted on the image forming unit 100. It is configured. An automatic document feeder (ADF) 400 is attached on the scanner 300.

  The scanner 300 is placed on the contact glass 301 as the first traveling body 303 mounted with a document illumination light source, a mirror, and the like and the second traveling body 304 mounted with a plurality of reflecting mirrors reciprocate. A reading scan of a document (not shown) is performed. The scanning light sent out from the second traveling body 304 is condensed on the imaging surface of the reading sensor 306 installed behind the imaging lens 305 and then read as an image signal by the reading sensor 306.

  The image forming unit 100 is provided with photosensitive drums 40Y, 40C, 40M, and 40Bk corresponding to toners of yellow (Y), cyan (C), magenta (M), and black (Bk) as latent image carriers. It has been. Around each photosensitive drum 40, various units for performing an electrophotographic process such as a developing device 70, a charging device 85, and a photosensitive member cleaning device 86 are arranged, and thereby each image forming unit 38 is formed. Four image forming units 38 are arranged in parallel, and the tandem type image forming unit 20 is formed thereby.

  In the developing device 70 of each image forming unit 38, the developer containing the above four color toners is used. In the developing device 70, a developing sleeve as a developer carrying member carries and conveys the developer, and an alternating electric field is applied at a position facing the photoconductor drum 40 to develop the latent image on the photoconductor drum 40. By applying the alternating electric field, the developer is activated, the charge amount distribution of the toner can be narrowed, and the developability can be improved. Further, the developing device 70 can be integrally supported together with the photosensitive drum 40, and can be formed detachably with respect to the image forming unit 100 to form a process cartridge. Accordingly, the developing device 70 and the photosensitive drum 40 can be easily attached to and detached from the image forming unit 100, and the maintainability can be improved. The process cartridge may further include a charging device 85 and a photosensitive member cleaning device 86.

  Above the tandem-type image forming unit 20, an exposure device 31 is provided that forms a latent image by exposing the photosensitive drum 40 with laser light or LED light based on image information.

  Further, an intermediate transfer belt 15 made of an endless belt member is disposed at a lower position facing the photosensitive drum 40 of the tandem type image forming unit 20. The intermediate transfer belt 15 is supported by a support roller 34, a support roller 35, and a secondary transfer backup roller 36. A primary transfer device 62 that transfers the toner images of the respective colors formed on the photosensitive drum 40 to the intermediate transfer belt 15 is disposed at a position adjacent to the photosensitive drum 40 via the intermediate transfer belt 15.

  Below the intermediate transfer belt 15, the toner images formed on the surface of the intermediate transfer belt 15 are collectively transferred onto the transfer paper P that is a recording medium conveyed from the paper feed cassette 44 of the paper feed table 200. A secondary transfer device 19 is arranged. The secondary transfer device 19 includes a secondary transfer roller 23 and a contact / separation mechanism (not shown) that supports the secondary transfer roller 23 so as to be able to contact and separate from the intermediate transfer belt 15. The secondary transfer device 19 presses the secondary transfer roller 23 against the secondary transfer backup roller 36 via the intermediate transfer belt 15 to transfer the toner image on the intermediate transfer belt 15 onto the transfer paper P.

  An intermediate transfer belt cleaning unit 37 is provided to remove toner remaining on the surface of the intermediate transfer belt 15. The intermediate transfer belt cleaning unit 37 causes a cleaning blade made of, for example, a fur brush or urethane rubber to contact the intermediate transfer belt 15 and scrapes off secondary transfer residual toner attached to the intermediate transfer belt 15.

  A fixing device 60 is provided adjacent to the secondary transfer device 19, and the fixing device 60 fixes an image on the transfer paper P. The fixing device 60 mainly includes a heating roller 66 in which a heater as a heat source is incorporated, and a pressure roller 67 pressed against the heating roller 66.

  A reversing device 28 for reversing the transfer paper P is disposed below the secondary transfer device 19 and the fixing device 60. The reversing device 28 reverses the transfer paper P to record images on both sides of the transfer paper P.

  Here, FIG. 1 shows the copying machine from the front side, with the rear side in the direction orthogonal to the drawing sheet being the rear side of the copying machine and the front side being the front side of the copying machine. The left side in the figure is the left side of the copying machine, and the right side in the figure is the right side of the copying machine. A front door that can be opened and closed is provided at the front of the casing of the copying machine. By opening the front door, the front surface of each image forming unit 38 is exposed to the outside. Each image forming unit 38 can be pulled out from the image forming unit 100 by sliding from the rear side to the front side of the copying machine with the front surface exposed in this manner. A rear side plate (not shown) is provided at the rear part of the casing of the copying machine.

  Next, the operation of the copying machine configured as described above will be described. The document is set on the document table 30 of the automatic document feeder 400, or the automatic document feeder 400 is opened, the document is set on the contact glass 301 of the scanner 300, and the automatic document feeder 400 is closed. When a start switch (not shown) is pressed in this state, when the document is set on the automatic document feeder 400, the document is transported and moved onto the contact glass 301. Thereafter, when a document is set on the other contact glass 301, the scanner 300 is immediately driven to cause the first traveling body 303 and the second traveling body 304 to travel. The first traveling body 303 irradiates light from the light source and receives reflected light from the document surface, and reflects it toward the second traveling body 304. The reflected light is further reflected by the mirror of the second traveling body 304 and is incident on the reading sensor 306 through the imaging lens 305, and the reading sensor 306 reads the content of the document.

  Further, by pressing a start switch of the apparatus, a drive motor (not shown) is driven to rotate and drive one of the support roller 34, the support roller 35, and the secondary transfer backup roller 36, and the other two support rollers are moved. Rotate following. As a result, the intermediate transfer belt 15 is rotated. At the same time, in each image forming unit 38, the photosensitive drum 40 is uniformly charged by the charging device 85, and then writing light from a laser, LED, or the like is emitted from the exposure device 31 according to the reading content of the scanner 300. By irradiating the writing light, an electrostatic latent image is formed on each charged photosensitive drum 40. Toner is supplied from the developing device 70 to the photosensitive drum 40 on which the electrostatic latent image is formed, and the electrostatic latent image is visualized. On each photosensitive drum 40, black (Bk), yellow (Y), A magenta (M) and cyan (C) single color image is formed. A single color image is sequentially primary transferred by the primary transfer device 62 so as to overlap the intermediate transfer belt 15, and a composite color image is formed on the intermediate transfer belt 15. Residual toner is removed from the surface of the photosensitive drum 40 after the image transfer by the photosensitive member cleaning device 86, and the static electricity is removed by a neutralizing device (not shown) to prepare for image formation again.

  Also, by pressing the start switch, one of the paper feed rollers 42 of the paper feed table 200 is selected and rotated, and the transfer paper P is fed out from one of the paper feed cassettes 44 provided in multiple stages in the paper bank 43. The transferred transfer paper P is separated one by one by the separation roller 45 and inserted into the paper feed path 46, conveyed by the conveyance roller pair 47 and guided to the paper supply path 48 in the image forming unit 100, and the registration roller pair Stop at 49. Thereafter, the registration roller pair 49 is rotated in synchronization with the composite color image on the intermediate transfer belt 15, and the transfer paper P is fed between the intermediate transfer belt 15 and the secondary transfer device 19. A color image is transferred onto the transfer paper P.

  Then, the transfer paper P carrying the unfixed toner image that has passed through the secondary transfer roller 23 is conveyed to the fixing device 60, and heat and pressure are applied by the fixing device 60 to fix the transferred image as a permanent image. The transfer paper P after image fixing is switched by the switching claw 55 and discharged by the discharge roller pair 56 and stacked on the paper discharge tray 57 or switched by the switching claw 55 and introduced into the reversing device 28. When the paper is introduced into the reversing device 28, the reversing device 28 reverses the transfer paper P and guides it to the transfer position again to record an image on the back surface. To do. At this time, residual toner remaining on the intermediate transfer belt 15 after the image transfer is removed by the intermediate transfer belt cleaning unit 37 to prepare for re-image formation by the tandem type image forming unit 20. Such a series of image forming operations is performed by controlling each device and each part in the copying machine such as the developing device 70 by a control device (not shown) of the copying machine main body.

  When the image forming operation as described above continues for a long time, the temperature of the image forming unit 38 rises due to heat generated by the photosensitive drum 40, which is a rotating member, and the developing roller itself, and transfer of heat from the fixing device 60. Then, the temperature in the developing device 70 of the image forming unit 38 also rises, and the toner in the developing device 70 is melted and fixed, and there is a possibility that the device stops or breaks.

  Therefore, the temperature in the developing device 70 needs to be equal to or lower than the temperature at which the toner melts. Therefore, in this embodiment, a liquid cooling type cooling device 10 that reduces the temperature rise in the developing device 70 by bringing a heat receiving portion (cooling jacket) through which the cooling liquid flows into contact with the side surface of the developing device 70 is mounted in the copying machine. is doing. Hereinafter, a copying machine including the liquid cooling type cooling device 10 which is a feature of the present embodiment will be described with reference to examples.

Example 1
First, Example 1 which is a first example of the present embodiment will be described with reference to the drawings. FIG. 2 is a schematic configuration diagram of the cooling device according to the present embodiment, and FIG. 3 is a table showing control targets of the pump flow rate with respect to the total liquid leakage amount detected by each liquid amount detection sensor.

  As shown in FIG. 2, the cooling device 10 of this embodiment includes a heat receiving portion 2Y, 2C, 2M, 2Bk, a tank 3 that is a storage portion, a pump 1 that is a liquid feeding portion, and a corrugated fin type radiator that is a heat radiating portion. 5a, which is composed of a pipe 4 which is a pipe line portion. Each part and the pipe 4 are connected by a rubber tube 410. In this way, each part of the cooling device 10 is connected by the pipe 4 and the rubber tube 410 to form a coolant circulation path for the coolant. Further, in the cooling device 10 of the present embodiment, each of the heat receiving portions 2Y, C, M, Bk, the tank 3, the radiator 5a, and the pipe 4 are all made of aluminum.

  The coolant in the coolant circulation path returns from the pump 1 through the pipe 4 and the rubber tube 410 to the pump 1 again through the radiator 5a, the heat receiving portions 2Y, 2C, 2M, and 2Bk and the tank 3. The heat receiving portions 2Y, 2C, 2M, and 2Bk are in close contact with the side surfaces of the corresponding developing devices 70Y, 70C, 70M, and 70Bk via heat conductive sheets made of low hardness silicone. Moreover, since the casing of each developing device 70 is made of aluminum and has high thermal conductivity, the developer can be cooled in the entire casing by cooling the side surface.

  In order to reduce the risk of liquid leakage in the coolant circulation path, it is desirable that the coolant circulation path of the cooling device 10 is all metallic. However, since each part constituting the cooling device 10 covers a wide range of the copying machine, the length is short enough to absorb the movement and vibration of the pipe 4 and the like in consideration of assembling property and maintenance workability. It connects with the rubber tube 410 so that it may become. And the part which comprises the cooling fluid circulation path of the cooling device 10 except the rubber tube 410 is comprised seamlessly with the metal, and a liquid leakage will generate | occur | produce only in the connection location by the rubber tube 410 under normal use environment. . In addition, propylene glycol that has water as the main component and lowers the freezing temperature, and a sufficient amount of rust preventive agent for the expected life of the copying machine of this embodiment are added to the cooling liquid. There will be no holes and no leakage.

  Below each connection portion by the rubber tube 410, an inclined resin (insulating) leaking liquid receiving tray 420 is disposed, and a liquid level detection sensor 421 as a leaked liquid level detecting means is provided on the lowermost surface thereof. It is fixed. When a liquid leak occurs at a connection location by the rubber tube 410, the leaked cooling liquid falls to the leaked liquid receiving tray 420. Further, a cover (not shown) whose lower surface is opened so as to surround the connection portion by the rubber tube 410 is provided on each leaking liquid receiving tray 420, and even when the cooling liquid leaks vigorously, the leaked cooling The liquid can be reliably received by each leaked liquid receiving tray 420. By configuring the coolant circulation path as described above, the location where the liquid leakage occurs under a normal use environment can be limited to the connection location by the rubber tube 410, and the leaked coolant can be reliably received by each leakage fluid receiving tray 420. It can be received at.

  The liquid amount detection sensor 421 provided in each leaking liquid receiving tray 420 measures the electrical resistance between two stainless steel electrodes vertically provided on the uppermost bottom surface of the leaking liquid receiving tray 420 and the electrodes. Consists of means (details, not shown). When a liquid leak occurs and the coolant flows into the leaked liquid receiving tray 420, the electrical resistance between the two electrodes changes depending on the immersion depth of the stainless steel electrode. Therefore, since the concave shape of the leaking liquid receiving tray 420 is known, the amount of cooling liquid on each leaking liquid receiving tray 420 by obtaining the immersion depth of the electrode from the electrical resistance, that is, the amount of liquid leaking at the connection location by the rubber tube 410 That is, the amount of leaked liquid can be determined.

  It is possible to determine whether or not a liquid leak has occurred in the cooling device 10 by obtaining the total amount of the cooling liquid amount on each leakage liquid tray 420, that is, the total leakage liquid amount (Lx). This is because when a liquid leak occurs, the coolant flows out of the cooling device 10 and the total leaked liquid amount (Lx) detected by each liquid quantity detection sensor 421 becomes a value larger than 0, It is because it can be judged that it has occurred. When a liquid leak occurs, it can be determined whether or not the liquid leak causes a serious problem that requires immediate repair or maintenance based on the detected total leaked liquid amount (Lx). That is, when the detected total leaked liquid amount (Lx) is less than a predetermined value (threshold value or the like), it can be determined that the liquid leak does not cause a serious problem. If such a determination is made, the copying machine can be operated while preventing a serious problem from occurring by controlling the operation of the copying machine to continue.

  Further, when it is determined that the liquid leakage does not cause a serious problem based on the detected total leakage liquid amount (Lx), the pump flow rate (V1) is controlled by the cooling control device 8 functioning as the liquid feeding unit control means. To do. By this control, it becomes possible to reduce the pressure of the coolant in the coolant circulation path so as to decrease the pump flow rate (V1) as the detected total leakage fluid amount (Lx) increases. Since the pump flow rate (V1) is lowered as the total leaked liquid amount (Lx) detected in this way increases and the pressure of the cooling liquid in the cooling liquid circulation path is lowered, the liquid leakage can be suppressed. The cooling performance can be maintained for a longer time compared to the conventional configuration in which the pump flow rate is not reduced. Therefore, when the operation of the copier is continued with a liquid leak that has a low possibility of causing a serious problem, the copier is operated for a longer time compared to the conventional configuration in which the pump flow rate is not adjusted while suppressing the liquid leak. Can continue.

  Further, the cooling device 10 of the present embodiment includes a cooling control device 8 having a function as a liquid feeding unit control means for controlling the pump 1 based on a detection signal (leakage liquid amount) of each liquid amount detection sensor 421. Yes. The cooling control device 8 communicates signals with the above-described control device of the copying machine main body to control the operation of each part of the cooling device 10, and at the same time, each device in the copying machine main body such as the developing device 70 and each part. Transmits signals necessary for control.

  Next, it demonstrates more concretely using FIG. In the cooling control device 8, as shown in the table of FIG. 3, the first threshold value (L1) and the second threshold value for the total leaked liquid amount (Lx), which is the total leaked liquid quantity detected by each liquid quantity detection sensor 421, A threshold value (L2) and a third threshold value (L3) are set. And the control target of the flow volume (henceforth a pump flow volume (V1)) of the cooling fluid by the pump 1 corresponding to each threshold value is set. Here, each threshold value satisfies a relationship of 0 <L1 <L2 <L3 <total cooling fluid amount in the cooling device 10. When the total leaked liquid amount (Lx) is 0 or more and less than L1, the pump flow rate (V1) is controlled to be the normal flow rate (V0). Further, when the total amount of leaked liquid is not less than L1 and less than L2, it is controlled to be 90% of the normal flow rate, and when the total amount of leaked liquid is not less than L2 and less than L3, it is controlled to be 70% of the normal flow rate. Further, when the total amount of leaked liquid reaches L3, the paper feeding of the pump 1 and the copying machine is stopped. That is, the operation of the copying machine as the image forming apparatus is stopped.

  In the present embodiment, the third threshold value (L3) is a liquid obtained in advance through experiments or the like that may reduce the cooling performance of the cooling device 10 due to a decrease in the cooling liquid in the cooling liquid circulation path (aeration). The amount of leakage. The first threshold (L1) is set to 50% of the third threshold (L3), and the second threshold (L2) is set to 80% of the third threshold (L3). And adjusting the pump flow rate (V1) according to the total amount of leaked liquid has the effect of reducing the pressure in the coolant circulation path and suppressing liquid leakage. That is, as the total leaked liquid amount (Lx) increases, the pump flow rate (V1) is decreased, thereby reducing the pressure in the coolant circulation path and suppressing the liquid leak. Therefore, as compared with the conventional configuration in which the pump flow rate is not adjusted (not reduced), the time until the total leakage liquid amount (Lx) reaches the third threshold (L3) and the paper feeding stops can be increased. In addition, each leaking liquid receiving tray 420 has a coolant leaking after the pump 1 is stopped so that the single leaking liquid receiving tray 420 does not overflow even if the third threshold (L3) amount of cooling liquid is received. Considering the amount, the capacity has a margin.

  In this way, in this embodiment, in the case of a liquid leak that is unlikely to cause a serious malfunction that does not require urgent repairs or maintenance, the liquid leak is suppressed while preventing a serious malfunction in advance. However, the operation of the image forming apparatus can be continued. Therefore, as compared with the conventional configuration in which the pump flow rate is not reduced, the total amount of leaked liquid (Lx) reaches the second threshold (L3), and the time until the pump 1 and the copying machine stop the paper passage can be lengthened.

  In the present embodiment, as described above, each threshold value and the pump flow rate (V1) are set with respect to the total leakage liquid amount (Lx). However, the combination of the threshold value of the total leakage liquid amount (Lx) and the pump flow rate (V1) is not limited to this, and the configuration of the liquid cooling type cooling device and the cooling performance of the cooling device with respect to the heat generation amount in the image forming apparatus. What is necessary is just to determine by a margin, the specification of an image forming apparatus, etc.

(Example 2)
Next, Example 2 which is a second example of the present embodiment will be described with reference to the drawings. FIG. 4 shows a control target of the pump flow rate (V1) based on the total leaked liquid amount (Lx) detected by each liquid level detection sensor 421 and the total leaked liquid amount (V2) per unit time. It is a table | surface which shows. In the present embodiment and the first embodiment described above, the cooling control device 8 of the copying machine of the present embodiment also applies to the total leaked liquid amount (V2) per unit time in addition to the total leaked liquid amount (Lx). The only difference is that it has the function of the liquid feed control means for controlling the pump flow rate (V1). Since other configurations and operations are the same, similar configurations and operations will be omitted as appropriate.

  In the cooling control device 8 of the present embodiment, the pump flow rate (V1) is controlled as shown in the table of FIG. In the cooling control device 8, the fourth threshold value (L4), the fifth threshold value (L5), and (0 <L4 <L5) are set for the total amount of leaked liquid (V2) per unit time. When the total leaked liquid amount (Lx) is 0 or more and less than the first threshold value (L1), and the total leaked liquid amount (V2) per unit time is 0 or more and less than the fourth threshold value (L4) The flow rate of the pump 1 is controlled to be the normal flow rate (V0). When the total leaked liquid amount (V2) per unit time is not less than the fourth threshold (L4) and less than the fifth threshold (L5), the flow rate of the pump 1 is controlled to be 70% of the normal flow rate (V0). To do. When the total amount of leaked liquid (V2) per unit time is equal to or greater than the fifth threshold (L5), control is performed to stop the pump and the copying machine from passing paper.

  The total leaked liquid amount (Lx) is not less than the first threshold (L1) and less than the second threshold (L2), and the total leaked liquid amount (V2) per unit time is not less than 0 and the fourth threshold (L4) If it is less, the flow rate of the pump 1 is controlled to be 90% of the normal flow rate (V0). When the total leaked liquid amount (V2) per unit time is not less than the fourth threshold (L4) and less than the fifth threshold (L5), the flow rate of the pump 1 is controlled to be 70% of the normal flow rate (V0). To do. When the total amount of leaked liquid (V2) per unit time is equal to or greater than the fifth threshold (L5), control is performed to stop the pump and the copying machine from passing paper.

  The total leaked liquid amount (Lx) is not less than the second threshold (L2) and less than the third threshold (L3), and the total leaked liquid amount (V2) per unit time is not less than 0 and the fifth threshold (L5) If it is less, the flow rate of the pump 1 is controlled to be 70% of the normal flow rate (V0). In addition, when the total leaked liquid amount (V2) per unit time is equal to or greater than the fifth threshold (L5), control is performed to stop the pump and the copying machine from passing paper. If the total leaked liquid amount (Lx) is equal to or greater than L3, control is performed to stop the pump and the copying machine regardless of the total leaked liquid amount (V2) per unit time. Do.

  In this embodiment, the fourth threshold value (L4) is set to 5% of the normal flow rate (V0), and the fifth threshold value (L5) is set to 10% of the normal flow rate (V0). Similar to the configuration of the first embodiment, by reducing the pump flow rate (V1), it is possible to reduce the pressure in the coolant circulation path and to suppress liquid leakage. In the cooling control device 8 of the present embodiment, the pump flow rate (V1) is defined for the total leaked liquid amount (V2) per unit time in addition to the total leaked liquid amount (Lx). The pump flow rate (V1) can be controlled more finely than in the first embodiment. Therefore, the time until the pump 1 and the paper passing are stopped can be made longer than that of the configuration of the first embodiment. In other words, in the case of a liquid leak that is unlikely to cause a serious malfunction, it is possible to prevent the serious malfunction, while maintaining the cooling performance by suppressing the liquid leak, and operating the copying machine, which is an image forming device. Can be continued longer than the configuration of the first embodiment.

  Further, in this example, as described above, each threshold value and the pump flow rate (V1) were set with respect to the total leakage liquid amount (V2) per unit time. However, the combination of the total leaked liquid amount (Lx), each threshold value of the total liquid leak amount per unit time, and the pump flow rate is not limited to this. It may be determined by the configuration of the liquid cooling type cooling device, the flow rate of the pump, the cooling performance of the cooling device with respect to the heat generation amount of the image forming device, the specifications of the image forming device, and the like.

(Example 3)
Next, Example 3 which is a third example of the present embodiment will be described with reference to the drawings. FIG. 5 is a schematic configuration diagram of the cooling device according to the present embodiment. FIG. 6 shows the pump flow rate (V1) and fan rotation based on the total leaked liquid amount (Lx) detected by each liquid level detection sensor 421 and the total leaked liquid amount (V2) per unit time. It is a control flow figure of a number. In the present embodiment and the above-described second embodiment, the cooling control device 8 of the copying machine of the present embodiment has a function of controlling the number of rotations of the cooling fan 5b in addition to the function of the liquid feeding unit control means for controlling the pump 1. The only difference is that it also has a function of the fan control means. Other configurations and operations are the same as those in the second embodiment, and therefore similar configurations and operations will be omitted as appropriate.

  As shown in FIG. 5, the configuration of the cooling device 10 of this embodiment also has the function of the cooling fan control means in which the configuration of the second embodiment and the cooling control device 8 control the rotation speed of the cooling fan 5b. It is the same except for the point which concerns. As shown in the flow chart of FIG. 6A, the pump flow rate (V1) and the fan rotation speed are compared with the total leaked liquid amount (V2) per unit time detected by each liquid amount detection sensor 421. Control can be performed. Specifically, the pump flow rate (V1) is controlled based on the total leaked liquid amount (V2) per unit time detected by the liquid control sensor 421 by the cooling control device 8, and in addition, the pump flow rate (V1) ) To control the rotational speed of the cooling fan 5b. Further, the radiator 5a dissipates heat by taking air outside the apparatus into the apparatus by the cooling fan 5b and transferring heat from the coolant flowing through the radiator 5a to the air through the fins. Therefore, the heat dissipation performance of the radiator 5a can be changed by changing the rotational speed of the cooling fan 5b.

  As shown in the control flow of FIG. 6, when the cooling device 10 is operated (S01), the pump flow rate (V1) is controlled to be the normal flow rate (V0) (S02), and the cooling fan 5b has the normal rotation speed. Control is performed as described above (S03). Thereafter, the total leaked liquid amount (Lx) is compared with the third threshold value (L3) (S04). If the total leaked liquid amount (Lx) is equal to or greater than the third threshold (L3) (Yes in S04), the paper feeding of the pump 1 and the copying machine is stopped (S05). On the other hand, when the total leaked liquid amount (Lx) is less than the third threshold value (L3) (No in S04), the total leaked liquid amount (Lx) is further compared with the second threshold value (L2) (S06).

  The total amount of leaked liquid (Lx) is compared with the second threshold (L2) (S06). If the total amount of leaked liquid (Lx) is equal to or greater than the second threshold (L2) (Yes in S06), the total per unit time The amount of leaked liquid (V2) is compared with the fifth threshold value (L5) (S07). When the total amount of leaked liquid (V2) per unit time is equal to or greater than the fifth threshold (L5) (Yes in S07), the paper feeding of the pump 1 and the copying machine is stopped (S08). On the other hand, when the total leaked liquid amount (V2) per unit time is less than the fifth threshold (L5) (No in S07), the pump flow rate (V1) is set to 70% of the normal flow rate (V0), and the cooling fan The rotational speed is increased by 20% of the normal rotational speed (S09). Thereafter, the process returns to the process (S04) of comparing the total leaked liquid amount (Lx) with the third threshold value (L3).

  Further, the total leaked liquid amount (Lx) is compared with the second threshold value (L2) (S06). When the total leaked liquid amount (Lx) is less than the second threshold value (L2) (No in S06), The amount of leaked liquid (Lx) is compared with the first threshold value (L1) (S10). When the total leaked liquid amount (Lx) is compared with the first threshold value (L1) (S10), and the total leaked liquid amount (Lx) is equal to or greater than the first threshold value (L1) (Yes in S10), the total per unit time The amount of leaked liquid (V2) is compared with the fifth threshold (L5) (S11). If the total amount of leaked liquid (V2) per unit time is equal to or greater than the fifth threshold (L5) (Yes in S11), the pump 1 and the copying machine are stopped (S12).

  When the total amount of leaked liquid (V2) per unit time is compared with the fifth threshold (L5) (S11), the total amount of leaked liquid (V2) per unit time is less than the fifth threshold (L5) ( Further, the total amount of leaked liquid (V2) per unit time is compared with the fourth threshold value (L4) (S13). When the total leaked liquid amount (V2) per unit time is equal to or greater than the fourth threshold value (L4) (Yes in S13), the pump flow rate (V1) is set to 70% of the normal flow rate (V0), and the rotation speed of the cooling fan is set. The normal rotational speed is increased by 20% (S14). Thereafter, the process returns to the process (S04) of comparing the total leaked liquid amount (Lx) with the third threshold value (L3). On the other hand, when the total leaked liquid amount (V2) per unit time is less than the fourth threshold (L4) (No in S13), the pump flow rate (V1) is set to 90% of the normal flow rate (V0), and the cooling fan The rotational speed is set to the normal rotational speed (S15). Thereafter, the process returns to the process (S04) of comparing the total leaked liquid amount (Lx) with the third threshold value (L3).

  When the total leaked liquid amount (Lx) and the first threshold value (L1) are compared (S10), and the total leaked liquid amount (Lx) is less than the first threshold value (L1) (No in S10), the unit per unit time The total leaked liquid amount (V2) is compared with the fifth threshold value (L5) (S16). If the total leaked liquid amount (V2) per unit time is equal to or greater than the fifth threshold value (L5) (Yes in S16), the pump 1 and the copying machine are stopped (S17). On the other hand, when the total leaked liquid amount (V2) per unit time is less than the fifth threshold (L5) (No in S16), the total leaked liquid amount (V2) per unit time is further set to the fourth threshold (L4). (S18). When the total leaked liquid amount (V2) per unit time is equal to or greater than the fourth threshold (L4) (Yes in S18), the pump flow rate (V1) is set to 70% of the normal flow rate (V0), and the number of rotations of the cooling fan is set. The normal rotational speed is increased by 20% (S19). Thereafter, the process returns to the process (S04) of comparing the total leaked liquid amount (Lx) with the third threshold value (L3).

  When the total leaked liquid amount (V2) per unit time is compared with the fourth threshold (L4) (S18), the total leaked liquid amount (V2) per unit time is less than the fourth threshold (L4) (S18). No), the pump flow rate (V1) is set to the normal flow rate (V0), and the rotation speed of the cooling fan is set to the normal rotation speed (S20). Thereafter, the process returns to the process (S04) of comparing the total leaked liquid amount (Lx) with the third threshold value (L3).

  Normally, when the pump flow rate (V1) is decreased, the cooling performance of the cooling device 10 is decreased. This is because the temperature increase of the coolant due to heat absorption increases, or the heat transfer coefficient between the respective flow path surfaces and the coolant decreases in each heat receiving part 2 and the radiator 5a due to the decrease in the flow rate of the coolant, This is because the cooling performance of the cooling device 10 decreases.

  Therefore, in the cooling control device 8 of the present embodiment, when the pump flow rate (V1) is reduced to 70% or less, the rotational speed of the cooling fan 5b is increased by 20% at the same time, the air volume of the cooling fan 5b is increased, and the air The amount of heat transferred by the airflow is increased. Further, since the heat transfer coefficient between the fin surface of the radiator 5a and air increases as the wind speed of the cooling fan 5b increases, the heat exchange efficiency of the cooling fan 5b is also improved. With this configuration, even when the pump flow rate (V1) is decreased, the cooling performance decrease of the cooling device 10 can be reduced. Accordingly, the time required to stop the pump 1 and the sheet passing can be made longer than the configuration of the second embodiment while maintaining the cooling performance of the cooling device 10 as much as possible. In other words, in the case of a liquid leak that is unlikely to cause a serious malfunction, it is possible to prevent the serious malfunction, while maintaining the cooling performance by suppressing the liquid leak, and operating the copying machine, which is an image forming device. Can be continued longer than the configuration of the second embodiment.

  In the present embodiment, as described above, the threshold value, the pump flow rate (V1), and the rotation speed of the cooling fan are set for the total leaked liquid amount (Lx) and the total leaked liquid amount per unit time (V2). Set. However, the combination of the total leaked liquid amount (Lx), the threshold values for the total leaked liquid amount per unit time (V2), the pump flow rate (V1), and the number of rotations of the cooling fan is not limited to this. It may be determined according to the configuration of the liquid cooling type cooling device, the pump flow rate, the cooling capacity of the cooling device with respect to the heat generation amount in the image forming device, the specifications of the image forming device, and the like. In the present embodiment, the cooling control device 8 controls the number of rotations of the cooling fan in accordance with the pump flow rate (V1) that is a set value of the cooling control device 8. However, the present invention is not limited to such a configuration, and it is also possible to provide a coolant flow rate sensor in the cooling device and control the number of rotations of the cooling fan based on the detection amount of the coolant flow rate sensor.

Example 4
Next, Example 4 which is the 4th example of this embodiment is explained using a figure. FIG. 7 shows the flow rate per unit time based on the total leaked liquid amount (Lx) detected by each liquid level detection sensor 421 and the pump flow rate (V1) derived from the total leaked liquid amount (Lx). It is a table | surface which shows the number of papers (PN). In the present embodiment and the first embodiment described above, only the following points are different. The cooling control device 8 of the copying machine according to the present embodiment controls the number of sheets passed per unit time (PN) based on the pump flow rate (V1) in addition to the function of the liquid feeding unit control means for controlling the pump 1. It is a point concerning having also the function of a control means. The method for controlling the pump flow rate (V1) based on the total leaked liquid amount (Lx) is the same as in the first embodiment. Since other configurations and operations are the same as those in the first embodiment, the similar configurations and operations will be omitted as appropriate.

  In the cooling control device 8 of the present embodiment, as shown in the table of FIG. 7, when the pump flow rate (V1) is a normal flow rate (V0) (0 ≦ Lx <L1), the number of sheets passed (PN) per unit time is set. Control is performed as the number of normal sheets (PN0). Further, when the pump flow rate (V1) is 90% of the normal flow rate (L1 ≦ Lx <L2), the number of paper passing (PN) per unit time is controlled to 80% of the normal paper passing number (PN0). In addition, when the pump flow rate (V1) is 70% of the normal flow rate (PN0) (L2 ≦ Lx <L3), the number of paper passing per unit time (PN) is set to 60% of the normal paper passing number (PN0). ing. When the pump flow rate is 0%, that is, in a state where the pump 1 is stopped (L3 ≦ Lx), similarly to the first embodiment, the paper feeding of the copying machine as the image forming apparatus is also stopped.

  Normally, when the pump flow rate (V1) is decreased, the cooling performance of the cooling device 10 is decreased. This is because the temperature increase of the coolant due to heat absorption increases, or the heat transfer coefficient between the respective flow path surfaces and the coolant decreases in each heat receiving part 2 and the radiator 5a due to the decrease in the flow rate of the coolant, This is because the cooling performance of the cooling device 10 decreases.

  Therefore, the cooling control device 8 of this embodiment sends a signal to the control device of the copying machine main body so that the heat generation amount in the fixing device 60 and each developing device 70 also decreases as the number of sheets passed per unit time decreases. Are controlled (fixing: reduction in input power, development: reduction in stirring speed). Further, the cooling control device 8 sends a signal to the control device of the copying machine main body so as to reduce the number of paper passing (PN) per unit time in accordance with the decrease in the pump flow rate (V1). By controlling the cooling control device 8 in this way, it becomes possible to prevent the developer temperature from increasing even if the pump flow rate (V1) is decreased. In other words, the number of sheets passed per unit time (PN) of the copying machine is controlled to suppress the amount of heat generated by the developing device 70 in contact with each heat receiving unit 2, and even if the pump flow rate (V 1) is reduced, the cooling is performed. It becomes possible to compensate for the cooling performance degradation of the apparatus 10. Here, the number of paper passing per unit time (PN) to be reduced in accordance with the reduction of the pump flow rate (V1) is a reduction in cooling performance due to a reduction in pump flow rate and a heat generation suppression effect due to a reduction in the number of paper passing per unit time in advance. It is required to conduct experiments and simulations.

  Thus, in the present embodiment, as shown in the table of FIG. 7, the cooling control device 8 uses the number control unit to transmit the information per unit time based on the information on the pump flow rate (V1) from the pump control unit. The number of sheets (PN) is controlled. Therefore, the number of sheets passed (PN) per unit time is reduced in accordance with the cooling performance of the cooling device 10 due to the reduction of the coolant flow rate in the coolant circulation path, that is, the pump flow rate (V1). The amount of heat generated by the developing device 70 can be suppressed. As described above, the heat generation amount of the developing device 70 of the copying machine, which is an image forming apparatus, can be suppressed, and even if the pump flow rate (V1) is reduced, the cooling performance of the cooling device 10 can be compensated for. . Accordingly, the time required to stop the pump 1 and the sheet passing can be made even longer than the configuration of the first embodiment, while the copier as the image forming apparatus can be suppressed while suppressing the heat generation amount itself. In other words, in the case of a liquid leak that is unlikely to cause a serious malfunction, the copier, which is an image forming apparatus, maintains the necessary cooling performance by suppressing the liquid leak while preventing a serious malfunction. Can be continued longer than the configuration of the first embodiment.

  In addition, since the number of paper passing per unit time (PN) to be reduced in accordance with the decrease in the pump flow rate (V1) is obtained in advance through experiments or simulations, it is necessary to measure or derive the cooling performance and heat generation amount online. There is no. Therefore, the device configuration and control of the cooling device 10 can be simplified.

  Further, in the cooling control device 8 of this embodiment, the number of sheets passed per unit time (PN) is made to correspond to each range of the pump flow rate (V1) derived from the total amount of leaked liquid (Lx), and the number of sheets normally passed ( PN0) and 80% and 60% of the normal sheet passing number (PN0). In addition, when the pump 1 is stopped (L3 ≦ Lx), control to stop is performed. However, the combination of the total leaked liquid amount (Lx), the pump flow rate (V1), and the number of sheets passed (PN) per unit time is not limited to this. It may be determined according to the configuration of the liquid cooling type cooling device, the pump flow rate, the cooling capacity of the cooling device with respect to the heat generation amount in the image forming device, the specifications of the image forming device, and the like.

(Example 5)
Next, Example 5 which is a fifth example of the present embodiment will be described with reference to the drawings. FIG. 8 shows a control target of the pump flow rate (V1) based on the total leaked liquid amount (Lx) detected by each liquid level detection sensor 421 and the total leaked liquid amount (V2) per unit time. And a continuous paper passing time. FIG. 9 is a control flow diagram of the pump flow rate and the continuous sheet passing time based on the total leaked liquid amount detected by each liquid amount detection sensor 421 and the total leaked liquid amount per unit time according to the present embodiment. FIG. 10 is a diagram showing a temporal change in the developer temperature in a color having the highest developer temperature when the pump flow rate is a normal flow rate and the continuous sheet passing time is not limited. FIG. 11 is a diagram showing a temporal change of the developer temperature in the color having the highest developer temperature when the pump flow rate is 70% of the flow rate and the continuous sheet passing time is 5 hours. is there.

  In the present embodiment and the second embodiment described above, the cooling control device 8 of the copying machine of the present embodiment has a continuous paper passing time of the copying machine based on the pump flow rate (V1) in addition to the function of the liquid feeding unit control means. The only difference is that it also functions as a sheet passing time control means for controlling. Other configurations / operations and the like are the same as those in the second embodiment, and therefore similar configurations / operations and the like will be omitted as appropriate.

  In the cooling control device 8 of this embodiment, as shown in the table of FIG. 8, the pump flow rate (V1) and the continuous paper passing time of the copying machine are controlled. When the total leaked liquid amount (Lx) is 0 or more and less than the first threshold (L1), and the total leaked liquid amount (V2) per unit time is 0 or more and less than the fourth threshold (L4), the pump The flow rate (V1) is set to the normal flow rate (V0), and the continuous paper passing time is not limited. When the total leaked liquid amount (V2) per unit time is not less than the fourth threshold value (L4) and less than the fifth threshold value (L5), the pump flow rate (V1) is set to 70% of the normal flow rate (V0), The paper time is controlled as 5 hours. When the total amount of leaked liquid (V2) per unit time is equal to or greater than the fifth threshold (L5), control is performed to stop the pump and the copying machine from passing paper.

  The total leaked liquid amount (Lx) is not less than the first threshold (L1) and less than the second threshold (L2), and the total leaked liquid amount (V2) per unit time is not less than 0 and the fourth threshold (L4) If the flow rate is less than 90%, the pump flow rate (V1) is set to 90% of the normal flow rate (V0), and the continuous sheet passing time is controlled to 10 hours. When the total leaked liquid amount (V2) per unit time is not less than the fourth threshold value (L4) and less than the fifth threshold value (L5), the pump flow rate (V1) is set to 70% of the normal flow rate (V0), The paper time is controlled as 5 hours. When the total amount of leaked liquid (V2) per unit time is equal to or greater than the fifth threshold (L5), control is performed to stop the pump and the copying machine from passing paper.

  The total leaked liquid amount (Lx) is not less than the second threshold (L2) and less than the third threshold (L3), and the total leaked liquid amount (V2) per unit time is not less than 0 and the fifth threshold (L5) If the flow rate is less than 70%, the pump flow rate (V1) is set to 70% of the normal flow rate (V0), and the continuous sheet passing time is controlled to 5 hours. In addition, when the total leaked liquid amount (V2) per unit time is equal to or greater than the fifth threshold (L5), control is performed to stop the pump and the copying machine from passing paper. If the total leaked liquid amount (Lx) is equal to or greater than L3, control is performed to stop the pump and the copying machine regardless of the total leaked liquid amount (V2) per unit time. Do.

  Next, the above-described control will be described more specifically using the control flow of FIG. First, when the cooling device 10 is operated (S101), the pump flow rate (V1) is controlled so as to become the normal flow rate (V0) (S102), and the continuous sheet passing time is not limited (S103). Thereafter, the total leaked liquid amount (Lx) is compared with the third threshold (L3) (S104). If the total leaked liquid amount (Lx) is equal to or greater than the third threshold (L3) (Yes in S104), the paper feeding of the pump 1 and the copying machine is stopped (S105). On the other hand, when the total leakage liquid amount (Lx) is less than the third threshold value (L3) (No in S104), the total leakage liquid amount (Lx) is further compared with the second threshold value (L2) (S106).

  The total leaked liquid amount (Lx) is compared with the second threshold value (L2) (S106). If the total leaked liquid amount (Lx) is equal to or greater than the second threshold value (L2) (Yes in S106), the total per unit time The amount of leaked liquid (V2) is compared with the fifth threshold value (L5) (S107). If the total leaked liquid amount (V2) per unit time is equal to or greater than the fifth threshold value (L5) (Yes in S107), the pump 1 and the copying machine are stopped (S108). On the other hand, when the total leaked liquid amount (V2) per unit time is less than the fifth threshold value (L5) (No in S107), the pump flow rate (V1) is set to 70% of the normal flow rate (V0), and continuous paper passing is performed. The time is limited to 5 hours (S109). Thereafter, the process returns to the process of comparing the total leaked liquid amount (Lx) with the third threshold (L3) (S104).

  Further, the total leaked liquid amount (Lx) is compared with the second threshold value (L2) (S106). When the total leaked liquid amount (Lx) is less than the second threshold value (L2) (No in S106), The amount of leaked liquid (Lx) is compared with the first threshold (L1) (S110). When the total leaked liquid amount (Lx) is compared with the first threshold value (L1) (S110) and the total leaked liquid amount (Lx) is equal to or greater than the first threshold value (L1) (Yes in S110), the total per unit time The amount of leaked liquid (V2) is compared with the fifth threshold value (L5) (S111). When the total amount of leaked liquid (V2) per unit time is equal to or greater than the fifth threshold (L5) (Yes in S111), the pump 1 and the copying machine are stopped (S112).

  When the total leaked liquid amount per unit time (V2) is compared with the fifth threshold value (L5) (S111), the total leaked liquid amount per unit time (V2) is less than the fifth threshold value (L5) ( Further, the total amount of leaked liquid (V2) per unit time is compared with the fourth threshold (L4) (S113). When the total leaked liquid amount (V2) per unit time is equal to or greater than the fourth threshold value (L4) (Yes in S113), the pump flow rate (V1) is set to 70% of the normal flow rate (V0), and the continuous sheet passing time is 5 Time is limited (S114). Thereafter, the process returns to the process of comparing the total leaked liquid amount (Lx) with the third threshold (L3) (S104). On the other hand, when the total leaked liquid amount (V2) per unit time is less than the fourth threshold value (L4) (No in S113), the pump flow rate (V1) is set to 90% of the normal flow rate (V0), and continuous paper passing is performed. The time is limited to 10 hours (S115). Thereafter, the process returns to the process of comparing the total leaked liquid amount (Lx) with the third threshold (L3) (S104).

  When the total leaked liquid amount (Lx) is compared with the first threshold value (L1) (S110), and the total leaked liquid amount (Lx) is less than the first threshold value (L1) (No in S110), the unit per unit time The total leaked liquid amount (V2) is compared with the fifth threshold value (L5) (S116). If the total leaked liquid amount (V2) per unit time is equal to or greater than the fifth threshold value (L5) (Yes in S116), the paper feeding of the pump 1 and the copying machine is stopped (S117). On the other hand, when the total leaked liquid amount (V2) per unit time is less than the fifth threshold (L5) (No in S116), the total leaked liquid amount (V2) per unit time is further set to the fourth threshold (L4). (S118). When the total leaked liquid amount (V2) per unit time is equal to or greater than the fourth threshold value (L4) (Yes in S118), the pump flow rate (V1) is set to 70% of the normal flow rate (V0), and the continuous sheet passing time is 5 Time is limited (S119). Thereafter, the process returns to the process of comparing the total leaked liquid amount (Lx) with the third threshold (L3) (S104).

  When the total amount of leaked liquid (V2) per unit time is compared with the fourth threshold (L4) (S118), the total amount of leaked liquid (V2) per unit time is less than the fourth threshold (L4) (S118). No), the pump flow rate (V1) is set to the normal flow rate (V0), and the continuous paper passing time is not limited (S120). Thereafter, the process returns to the process of comparing the total leaked liquid amount (Lx) with the third threshold (L3) (S104).

  Normally, when the pump flow rate (V1) is decreased, the cooling performance of the cooling device 10 is decreased. This is because the temperature increase of the coolant due to heat absorption increases, or the heat transfer coefficient between the respective flow path surfaces and the coolant decreases in each heat receiving part 2 and the radiator 5a due to the decrease in the flow rate of the coolant, This is because the cooling performance of the cooling device 10 decreases.

  Therefore, in the cooling control device 8 of the present embodiment, the continuous paper passing time is limited so that the paper passing of the copying machine is stopped before the temperature of the developer in each developing device 70 becomes higher than the allowable maximum temperature. I do. Here, as shown in FIG. 10, when the pump flow rate (V1) is the normal flow rate (V0), the cooling performance of the cooling device 10 is sufficiently high, so that the developer of the color having the highest developer temperature is the allowable maximum temperature. Saturates below. However, when the pump flow rate (V1) is 70% of the normal value, the cooling performance of the liquid cooling system is deteriorated. Therefore, when the sheet is continuously fed, the developer rises above the allowable maximum temperature. Therefore, in this embodiment, as shown in FIG. 11, the continuous paper passing time is limited to 5 hours, and when the continuous paper passing time reaches 5 hours, the paper feeding is stopped before the developer reaches the allowable maximum temperature. Then, the paper feeding stop time is 30 minutes and the paper feeding is started again. By setting the sheet passing stop time to 30 minutes, the developer temperature does not reach the allowable maximum temperature even if continuous sheet passing is performed for 5 hours after the sheet passing stop time has elapsed. Further, when the pump flow rate (V1) is 90% of the normal value, the continuous paper passing time is limited to 10 hours, and when the continuous paper passing time reaches 10 hours, the developer passes before the developer reaches the allowable maximum temperature. The paper is stopped, the paper passing stop time is 30 minutes, and paper feeding is started again. Here, the continuous paper passing time and the paper passing stop time correspond to a decrease in cooling performance, a decrease in cooling performance, a rise in developer temperature due to continuous paper passing, and a stop of paper passing in advance. The temperature drop is regulated through experiments and simulations.

  In this way, the developer temperature is higher than the allowable maximum temperature even if the pump flow rate (V1) is reduced by limiting the continuous paper passing time and taking the paper passing stop time in accordance with the decrease in the pump flow rate (V1). It is possible not to become.

  In addition, since the continuous paper passing time and the paper passing stop time in accordance with the decrease in the pump flow rate (V1) are obtained in advance through experiments and simulations, it is not necessary to measure or derive the cooling performance or the heat generation amount online. . Therefore, the device configuration and control of the cooling device 10 can be simplified.

  Further, in this embodiment, the continuous flow time is not limited, corresponding to each range of the pump flow rate (V1) derived from the total leaked liquid amount (Lx) and the total leaked liquid amount per unit time (V2). The control is limited to 10 hours and 5 hours, and the sheet passing stop time is 30 minutes. However, the total leaked liquid amount (Lx), the respective threshold values for the total leaked liquid amount per unit time (V2), the pump flow rate (V1), and the combination of the continuous paper passing time and the paper passing stop time are not limited to this. It may be determined according to the configuration of the liquid cooling type cooling device, the pump flow rate, the cooling capacity of the cooling device with respect to the heat generation amount in the image forming device, the specifications of the image forming device, and the like.

In the above-described embodiment, the configuration in which the control device for the copying machine main body and the cooling control device 8 are provided separately has been described. However, the present invention is not limited to the configuration in which the copying machine main body control device and the cooling control device 8 are provided separately, and the copying machine main body control device and the cooling control device 8 may be combined.
Although a full-color color copying machine has been described as an example, the present invention is not limited to a full-color image forming apparatus, and can be applied to a single-color or multi-color image forming apparatus.
Also, the liquid cooling type cooling device 10 that cools each developing device 70 has been described, but the object to be cooled is not limited to the developing device, and each device and each part in the image forming apparatus that needs to be cooled are included. Can be applied.
Further, although an example of a copying machine used in a normal use environment has been described, the applicable use environment of an image forming apparatus is not limited to a normal use environment. The present invention can also be applied to an image forming apparatus that is used in an environment subject to impact. However, in an environment where excessive vibrations or impacts are received, there is an increased possibility of liquid leakage at an unexpected location. Therefore, the decrease liquid amount detection means and the decrease liquid amount detection means previously examined by the inventors are provided, the decrease liquid amount detected by the decrease liquid amount detection means, and the total leaked liquid amount detected by the leak liquid amount detection means. Based on the above, it is desirable to determine whether or not the liquid leakage causes a serious malfunction.

As described above, according to the copying machine that is the image forming apparatus of the present embodiment, the following operations and effects can be achieved. Each part in the coolant circulation path of the cooling device 10 and the pipe 4 are connected by a rubber tube 410, and a leakage receiving pan 420 and a liquid amount detection sensor 421 are provided below each connection part. Based on the amount of leaked liquid (Lx), it can be determined whether or not a liquid leak has occurred. This is because when a liquid leak occurs, the coolant flows out of the cooling device 10 and the total leaked liquid amount (Lx) detected by each liquid quantity detection sensor 421 becomes a value larger than 0, It is because it can be judged that it has occurred.
When a liquid leak occurs, it can be determined whether or not the liquid leak causes a serious problem that requires immediate repair or maintenance based on the detected total leaked liquid amount (Lx). That is, when the detected total leakage liquid amount (Lx) is less than the threshold value L3, it can be determined that the liquid leakage does not cause a serious problem. If such a determination is made, the copying machine can be operated while preventing a serious problem from occurring by controlling the operation of the copying machine to continue.
Further, when it is determined that the liquid leakage does not cause a serious problem based on the detected total leakage liquid amount (Lx), the pump flow rate (V1) is controlled by the cooling control device 8 functioning as the liquid feeding unit control means. To do. By this control, it becomes possible to reduce the pressure of the coolant in the coolant circulation path so as to decrease the pump flow rate (V1) as the detected total leakage fluid amount (Lx) increases. Since the pump flow rate (V1) is lowered as the total leaked liquid amount (Lx) detected in this way increases and the pressure of the cooling liquid in the cooling liquid circulation path is lowered, the liquid leakage can be suppressed. The cooling performance can be maintained for a longer time compared to the conventional configuration in which the pump flow rate is not reduced. Therefore, when the operation of the copier is continued with a liquid leak that has a low possibility of causing a serious problem, the copier is operated for a longer time compared to the conventional configuration in which the pump flow rate is not adjusted while suppressing the liquid leak. Can continue.
Therefore, in the case of a liquid leak that has a low possibility of causing a serious malfunction, the liquid cooling type cooling device 10 that can continue the operation of the copying machine while preventing the serious malfunction and suppressing the liquid leak is provided. A copier equipped can be provided. When the operation of the copying machine is continued, a copying machine including the liquid cooling type cooling device 10 that can continue the operation of the copying machine for a longer time than the configuration in which the flow rate of the cooling liquid in the cooling device 10 is not adjusted can be provided.
Further, according to the copying machine that is the image forming apparatus of the present embodiment, the following actions and effects can be achieved. The cooling control device 8 of the cooling device 10 controls the pump flow rate (V1) with respect to the total leaked liquid amount (V2) per unit time in addition to the total leaked liquid amount (Lx). It is also possible to control the pump flow rate (V1) more finely than controlling only (Lx). Therefore, the time until the pump 1 and the sheet passing are stopped can be made longer than controlling only the total leaked liquid amount (Lx). Therefore, in the case of a liquid leak that is unlikely to cause a serious malfunction, the liquid leakage is suppressed and the cooling performance is maintained while preventing the occurrence of a serious malfunction. The control can be continued longer than the control only for (Lx).
Further, according to the copying machine that is the image forming apparatus of the present embodiment, the following actions and effects can be achieved. The cooling control device 8 of the cooling device 10 has a function of a cooling fan control means for controlling the number of revolutions of the cooling fan 5b in addition to a function of a liquid feeding part control means for controlling the pump 1, so that the pump flow rate ( Decreasing the cooling performance of the cooling device 10 that decreases when V1) is reduced can be reduced. Specifically, when the pump flow rate (V1) is reduced to 70% or less, the number of rotations of the cooling fan 5b is increased by 20% at the same time to increase the air volume of the cooling fan 5b and increase the heat transfer amount by the air flow. Further, the cooling performance degradation of the cooling device 10 can be made smaller than the configuration in which the cooling fan control means is not provided. In other words, even when the rotational speed of the cooling fan 5b is not increased in accordance with the decrease in the pump flow rate, the operation of the copying machine can be suppressed from decreasing in the cooling performance of the cooling device 10. Therefore, even if the rotational speed of the cooling fan 5b is not increased in accordance with the decrease in the pump flow rate, the operation of the copying machine can be suppressed from decreasing the cooling performance of the cooling device 10, and the operation of the copying machine can be continued for a long time. Can be made.
Further, according to the copying machine that is the image forming apparatus of the present embodiment, the following actions and effects can be achieved. The cooling control device 8 of the cooling device 10 has a function of a sheet feeding unit control unit for controlling the number of sheets passing per unit time (PN) of the copying machine in addition to a function of a liquid feeding unit control unit for controlling the pump 1. Therefore, the calorific value itself of the developing device 70 of the copying machine can be suppressed as the pump flow rate (V1) decreases. In other words, the number of sheets passed per unit time (PN) of the copying machine is controlled to suppress the amount of heat generated by the developing device 70 in contact with each heat receiving unit 2, and even if the pump flow rate (V 1) is reduced, the cooling is performed. It becomes possible to compensate for the cooling performance degradation of the apparatus 10. Therefore, while suppressing the heat generation amount itself, the time until the pump 1 and the paper passing are stopped, the operation of the copying machine is adjusted to the decrease in the pump flow rate (V1), and the number of paper passing (PN) per unit time is set. It can be made even longer than a configuration that does not decrease. In addition, since the number of paper passing per unit time (PN) to be reduced in accordance with the decrease in the pump flow rate (V1) is obtained in advance through experiments or simulations, it is necessary to measure or derive the cooling performance and heat generation amount online. There is no. Therefore, the device configuration and control of the cooling device 10 can be simplified.
Further, according to the copying machine that is the image forming apparatus of the present embodiment, the following actions and effects can be achieved. The cooling control device 8 of the cooling device 10 has a function of a sheet feeding time control unit for controlling a continuous sheet feeding time of the copying machine in addition to a function of a liquid feeding unit control unit for controlling the pump 1. Accordingly, it is possible to perform the sheet passing while taking the sheet passing stop time at intervals corresponding to the decrease in the pump flow rate (V1). In other words, the operation of the copying machine can be continued while taking the paper passing stop time at intervals corresponding to the decrease in the pump flow rate (V1). By taking a paper passing stop time at intervals corresponding to the decrease in the pump flow rate (V1), the copying machine is stopped before the developer temperature in each developing device 70 becomes higher than the allowable maximum temperature. After the paper passing stop time has elapsed, the paper passing can be started again with the developer temperature lowered. Therefore, the amount of heat generated by the developing device 70 of the copying machine can be suppressed in accordance with a decrease in the cooling performance of the cooling device 10. Therefore, the time to stop the pump 1 and paper passing, while suppressing the calorific value itself, the operation of the copier while keeping the paper passing stop time at intervals according to the decrease of the pump flow rate (V1). Can be made even longer than a configuration that does not continue. Further, since the continuous paper passing time and the paper passing stop time that are controlled in accordance with the decrease in the pump flow rate (V1) are obtained in advance through experiments and simulations, it is necessary to measure or derive the cooling performance and heat generation amount online. Absent. Therefore, the device configuration and control of the cooling device 10 can be simplified.

DESCRIPTION OF SYMBOLS 1 Pump 2 Heat receiving part 3 Tank 4 Pipe 5a Radiator 5b Cooling fan 8 Cooling control apparatus 10 Cooling apparatus 20 Tandem type image forming part 38 Image forming unit 40 Photosensitive drum 60 Fixing apparatus 70 Developing apparatus 100 Image forming part 200 Paper feed table 300 Scanner 300 Optical device 400 Automatic document feeder 410 Rubber tube 420 Leaked liquid tray 421 Liquid level detection sensor

JP 2010-020090 A

Claims (5)

In the image forming apparatus provided with a cooling device that circulates the cooling liquid in the cooling liquid circulation path and cools the temperature rise portion,
The cooling liquid circulation path includes a heat receiving portion that is close to or in contact with the temperature rising portion, a heat radiating portion that radiates heat removed from the temperature rising portion by the heat receiving portion to the outside of the image forming apparatus, and a cooling liquid. The storage part to be stored, the liquid feed part for moving the coolant in the coolant circulation path, and the heat receiving part, the heat radiating part, the storage part, and the liquid feed part are communicated so that the coolant can circulate. It consists of a pipeline part,
The cooling device has a leakage amount detection means for detecting the leakage amount of the cooling liquid from the cooling liquid circulation path,
An image forming apparatus comprising: a liquid feeding unit control unit that controls a flow rate of the cooling liquid in the cooling device based on the leakage liquid amount detected by the leakage liquid amount detection unit. The image forming apparatus according to claim 1.
An image forming apparatus comprising: a liquid feeding unit control unit that controls a flow rate of the cooling liquid in the cooling device based on a leakage liquid amount per unit time detected by the leakage liquid amount detection unit. The image forming apparatus according to claim 1, wherein
The radiator is a radiator having a coolant flow path;
A cooling fan that blows air on the radiator,
An image forming apparatus comprising cooling fan control means for controlling the number of rotations of the cooling fan based on the flow rate of the cooling liquid in the cooling apparatus. The image forming apparatus according to any one of claims 1 to 3,
An image forming apparatus comprising: a sheet number control means for controlling the number of sheets to be subjected to image formation per unit time based on a flow rate of a cooling liquid in the cooling apparatus. The image forming apparatus according to any one of claims 1 to 4,
An image forming apparatus comprising: a sheet passing time control unit that controls a continuous sheet passing time based on a flow rate of a cooling liquid in the cooling device.

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