Patent Application
20240134311
The present invention relates to an air ventilation structure in an image forming apparatus.
An electrophotographic image forming apparatus includes a charger, which charges a photosensitive body, and a developing device, which develops an electrostatic latent image. Since the charger generates ozone, which oxidizes frames and the like, the ozone needs to be discharged. Since the developing device has an appropriate operating temperature assumed by design, the developing device needs to be cooled. Therefore, Japanese Patent Laid-Open No. H10-149081 proposes discharging air taken in from the outside of the image forming apparatus after circulating it in the image forming apparatus.
Incidentally, a sheet jam may occur in the image forming apparatus. The jammed sheet is removed by opening a maintenance door of the image forming apparatus. At this time, if unfixed toner present on the sheet is sucked into the image forming apparatus from an intake port, the charger will end up being soiled by the toner.
The present disclosure provide an image forming apparatus comprising: a housing; and an image forming unit provided in the housing and configured to form an image on a sheet, wherein the image forming unit includes: a photosensitive body; a charger configured to charge a surface of the photosensitive body; an exposure device configured to form an electrostatic latent image by exposing the surface of the photosensitive body; a developing device configured to form a toner image on the surface of the photosensitive body by developing the electrostatic latent image using toner; and a transfer roller configured to transfer the toner image from the photosensitive body to a sheet, and wherein the housing includes: a protective member configured to be switched between in a protective state in which the protective member is protecting a protection target and in a non-protective state in which the protective member is not protecting the protection target; an intake port configured to take in air; a duct configured to guide the air taken in from the intake port to the image forming unit and guide the air from the image forming unit to outside of the housing; an exhaust port connected to the duct and configured to discharge the air to outside of the housing; a fan provided in a section from the intake port to the exhaust port in the duct and configured to assist intake, discharging or both of intake and discharging of the air; and a processor configured to control the fan, wherein the processor is configured to, in a case where the protective member is in the protective state, permit rotation of the fan and, in a case where the protective member is in the non-protective state, restrict rotation of the fan.
Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings).
Hereinafter, embodiments will be described in detail with reference to the attached drawings. Note, the following embodiments are not intended to limit the scope of the claimed invention. Multiple features are described in the embodiments, but limitation is not made to an invention that requires all such features, and multiple such features may be combined as appropriate. Furthermore, in the attached drawings, the same reference numerals are given to the same or similar configurations, and redundant description thereof is omitted.
In the following, “U” of
<Image Forming System>
An image forming system 1X illustrated in
<Image Forming Apparatus>
The image forming apparatus 100 is a tandem full color printer for forming an image on a sheet S using an electrophotographic method. The image forming apparatus 100 includes a first housing 101a and a second housing 101b. The first housing 101a includes various devices (e.g., an image forming unit 700) and various members for conveying a sheet S and transferring toner images onto the sheet S.
The second housing 101b includes various devices (e.g., a fixing unit 800) and various members for conveying a sheet S and fixing toner images onto the sheet S. An operation unit 200 is disposed on an upper portion of the second housing 101b. The operation unit 200 includes a display apparatus capable of displaying various kinds of information and an input apparatus capable of inputting various kinds of information according to a user operation. The operation unit 200 is disposed so as to be operable by an operator standing on a front side of the image forming apparatus 100.
An electrical unit (not illustrated), which includes a power supply board, may be disposed on an inner back side of the first housing 101a and the second housing 101b. In the present specification, a side on which the operator stands when operating the operation unit 200 in order for the user to operate the image forming apparatus 100 is defined as the “front”. A side opposite to the front is defined as the “back”. A side surface of the image forming system 1X on the left side when the operator is looking at the image forming system 1X from the front side is defined as the “left side surface”. A side surface of the image forming system 1X on the right side when the operator is looking at the image forming system 1X from the front side is defined as the “right side surface”.
The image forming unit 700 includes image forming units Pa, Pb, Pc, and Pd. The image forming unit Pa forms a yellow image. The image forming unit Pb forms a magenta image. The image forming unit Pc forms a cyan image. The image forming unit Pd forms a black image. The image forming apparatus 100 forms toner images on a sheet S according to an image signal received from a document reading apparatus 190 for reading a document and generating an image signal or an external device (not illustrated), such as a personal computer (PC).
The image forming unit 700 is formed by the image forming units Pa to Pd, primary transfer rollers 24a to 24d, an intermediate transfer belt 130, a plurality of rollers 13 to 15, and an outer roller 11. A sheet S may be any of, for example, a sheet of paper material, such as plain paper, cardboard, rough paper, embossed paper, and coated paper, a sheet of resin material, such as such as plastic film, and a sheet of cloth material.
The image forming units Pa to Pd are arranged side by side (tandem type) along a direction of movement of the intermediate transfer belt 130. The intermediate transfer belt 130 is stretched over the rollers 13, 14, and 15 and moves (rotates) in the direction of an arrow R2. The intermediate transfer belt 130 carries and conveys toner images to be transferred as will be described later. The outer roller 11 is disposed at a position facing the roller 14. The outer roller 11 and an inner roller (roller 14) form a secondary transfer unit T2 for transferring the toner images on the intermediate transfer belt 130 onto a sheet S. The fixing unit 800 is disposed downstream of the secondary transfer unit T2 in a direction of conveyance of the sheet S.
A plurality of cassettes 10 (e.g., two cassettes) for storing sheets S are disposed below the image forming unit 700. The plurality of cassettes 10 each contain a difference size or thickness of sheets S. A sheet S is conveyed from the cassette 10 selected by the operator. The sheet S is fed from the cassette 10 to the conveyance path by a conveyance roller 16. Further, the sheet S is conveyed to a registration roller 12 via the conveyance path. The registration roller 12 rotates in synchronization with the toner images formed on the intermediate transfer belt 130 and conveys the sheet S to the secondary transfer unit T2. The present invention is not limited to the sheet S stored in the cassette 10, and the sheet S may be fed from a manual feeding unit (not illustrated) and conveyed to the secondary transfer unit T2.
The image forming units Pa, Pb, Pc, and Pd have substantially the same configuration except that the developing colors of the toner images are different. Therefore, in order to make the description common to the image forming units Pa, Pb, Pc, and Pd, the letters a, b, c, and d at the end of reference numerals assigned to members constituting the image forming unit P will be omitted.
A cylindrical photosensitive drum 3 is disposed as a photosensitive body in the image forming unit P. The photosensitive drum 3 is driven to rotate by a motor (not illustrated). A charger 2, an exposure device L, a developing device 1, a primary transfer roller 24, and a drum cleaning device 4 are disposed near the photosensitive drum 3.
The charger 2 uniformly charges the surface of the rotating photosensitive drum 3. The charger 2 is, for example, a corona charger for irradiating the surface of the photosensitive drum 3 with charged particles that accompany corona discharge. The exposure device L exposes the surface of the photosensitive drum 3 while scanning a laser beam that corresponds to an image signal. An electrostatic latent image that accords with the image signal is thus formed on the surface of the photosensitive drum 3. The developing device 1 forms a toner image by developing the electrostatic latent image formed on the surface of the photosensitive drum 3 using toner. The developing device 1, for example, stores developer, which includes toner and carrier. The developing device 1 circulates and transfers the developer while stirring it using a screw (not illustrated).
The photosensitive drum 3 conveys the toner image to a primary transfer unit T1. The primary transfer unit T1 is formed by the photosensitive drum 3 and the primary transfer roller 24. The primary transfer unit T1 transfers (primary-transfers) the toner image from the photosensitive drum 3 to the intermediate transfer belt 130. A primary transfer voltage for facilitating primary transfer is applied to the primary transfer roller 24. The drum cleaning device 4 cleans the toner not transferred to the intermediate transfer belt 130 and remaining on the surface of the photosensitive drum 3.
Such a primary transfer operation is sequentially performed in the respective yellow, magenta, cyan, and black image forming units Pa to Pd. The toner images of four colors are thus overlaid on the intermediate transfer belt 130, thereby forming a full color image.
The sheet S is conveyed from the cassette 10 to the secondary transfer unit T2 according to a toner image formation timing. A full-color toner image formed on the intermediate transfer belt 130 is transferred to the sheet S (secondary transfer) by a secondary transfer voltage being applied to the outer roller 11. The toner remaining on the intermediate transfer belt 130 is removed by a belt cleaning device (not illustrated). The belt cleaning device includes, for example, a cleaning blade and a toner collection container that are disposed so as to face the roller 13.
The sheet S to which the toner image has been transferred is conveyed to the fixing unit 800. The fixing unit 800 fixes the toner image onto the sheet S by applying heat and pressure to the sheet S to which the toner image has been transferred. According to
The first fixing device 81 includes a fixing roller 82 and a pressing belt 83. The fixing roller 82 and the pressing belt 83 form a fixing nip portion. The fixing roller 82 is a roller that can rotate while being in contact with the surface on which the toner image has been transferred between two surfaces of the sheet S. The pressing belt 83 rotates while pressing against the fixing roller 82. At least one of the fixing roller 82 and the pressing belt 83 is heated by a heater (not illustrated). When the sheet S passes through the fixing nip portion, heat and pressure are applied from the first fixing device 81, thereby fixing the toner image onto the sheet S.
The structure of the second fixing device 91 is the same as the structure of the first fixing device 81. The second fixing device 91 is disposed downstream of the first fixing device 81. The second fixing device 91 is selectively used, for example, for further applying gloss to the toner image on the sheet S. For example, when the sheet S is coated paper, such as glossy paper or synthetic paper, both the first fixing device 81 and the second fixing device 91 perform the fixing processing. In other words, upon passing through the first fixing device 81, the sheet S is guided to a fixing route 30a by a flapper 95 and fed to the second fixing device 91. Meanwhile, when the sheet S is non-coated paper such as plain paper, the first fixing device 81 performs the fixing processing, but the second fixing device 91 does not perform the fixing processing. Therefore, upon passing through the first fixing device 81, the sheet S is guided to a bypass route 30b for bypassing the second fixing device 91 by the flapper 95.
The image forming apparatus 100 can perform double-sided printing. In a case of one-sided printing, a flapper 160 guides the sheet S on which the toner image has been fixed to a conveyance path 150. The conveyance path 150 discharges the sheet S out of the image forming apparatus 100. In a case of double-sided printing, the flapper 160 guides the sheet S on which the toner image has been fixed to a conveyance path 600. The conveyance path 600 is formed across the first housing 101a and the second housing 101b. The conveyance path 600 reverses the front and back sides of the sheet S by a switchback operation. The conveyance path 600 conveys the sheet S to the registration roller 12. The registration roller 12 conveys the sheet S to the secondary transfer unit T2. The back side of the sheet S on which an image is not printed faces the intermediate transfer belt 130.
In the secondary transfer unit T2, a full-color toner image formed on the intermediate transfer belt 130 is transferred to the sheet S (back side). The toner image is then fixed onto the sheet S by the fixing unit 800, and the sheet S is discharged out of the image forming apparatus 100.
In
The finisher apparatus 300 is connected the image forming apparatus 100 such that the sheet S can be passed, and the sheet S discharged from the image forming apparatus 100 is conveyed to the finisher apparatus 300. The finisher apparatus 300 executes post-processing on the sheet S. The post-processing includes, for example, punching processing for punching holes in the sheet S and stapling processing for bundling and stapling a plurality of sheets S. The finisher apparatus 300 discharges the punched sheet S to a tray 301. The finisher apparatus 300 discharges the stapled bundle of sheets S to a tray 302.
A cover switch 194 is provided in
<Airflow>
The image forming apparatus 100 cools the inside of the image forming apparatus 100 by taking in air from the outside and discharging the air. Such flow of air is called airflow. First, an airflow related the developing devices 1a to 1d will be described.
A left front door 170a and a right front door 170b are provided on the front of the first housing 101a and are maintenance doors that function as an outer cover and can be opened and closed. In the present example, the left front door 170a and the right front door 170b are double doors. A hinge is provided at the left end of the left front door 170a. A hinge is also provided at the right end of the right front door 170b.
Door switches 192a and 192b are provided on the front surface 251 of the first housing 101a. The door switch 192a is disposed at a position at which it will be pressed by a protrusion 172a provided on the left front door 170a. That is, the door switch 192a can detect a state (protective state) in which the left front door 170a is closed and a state (non-protective state) in which the left front door 170a is not closed. The door switch 192b is disposed at a position at which it will be pressed by a protrusion 172b provided on the right front door 170b. That is, the door switch 192b can detect a state (protective state) in which the right front door 170b is closed and a state (non-protective state) in which the right front door 170b is not closed.
A top surface cover 171 is provided above the left front door 170a. A portion of the top surface cover 171 forms a protruding portion 257, which protrudes farther toward the front side of the image forming apparatus 100 than the left front door 170a in a closed state. Three intake ports 175 are formed on the lower surface of the protruding portion 257. For example, a filter for removing dust from the air that has been taken in may be attached to the openings of the three intake ports 175. There need only be one or more intake ports 175.
A cover 173 is provided on the front surface 251 of the first housing 101a. The cover 173 is covered by the left front door 170a and the right front door 170b when the left front door 170a and the right front door 170b are closed. The cover 173 can prevent the user from touching movable portions, electrical wires, and the like inside the first housing 101a. Meanwhile, a service person (person in charge of maintenance) needs to access and perform maintenance on the movable portions, electrical wires, and the like inside the first housing 101a. The cover 173 is provided on the first housing 101a so as to be capable of being attached and detached by a lock lever 185. The service person detaches the cover 173 by releasing the lock lever 185 and accesses the inside of the first housing 101a. The cover 173 has four openings 208 through which the image forming units Pa to Pd can be individually inserted and removed from the first housing 101a. The four openings 208 are each provided with a member 209, which covers a corresponding one of the image forming units Pa to Pd and is capable of being attached and detached.
The cover switch 194 illustrated in
As illustrated in
The intake fans 180b, 180c, and 180d and the side duct 174b are provided on the right side surface of the main body duct 174. The intake fans 180b, 180c, and 180d are fans for taking in air from the three intake ports 175 and supplying the air to the developing devices 1b, 1c, and 1d, respectively.
A connection portion that connects with the intake fans 180b, 180c, and 180d is formed on the right side surface of the main body duct 174. The air taken in from the intake ports 175 passes through the inside of the main body duct 174 and enters the intake fans 180b, 180c, 180d via the connection portion.
As illustrated in
As illustrated in
As illustrated in
As illustrated in
As illustrated in
An inlet 229a of the relay duct 228a is connected with the outlet 182a of the side duct 174a. An outlet 230a of the relay duct 228a is connected with the outlet joint 184a. An inlet 229b of the relay duct 228b is connected with the outlet 182b of the side duct 174b. An outlet 230b of the relay duct 228b is connected with the outlet joint 184b. An inlet 229c of the relay duct 228c is connected with the outlet 182c of the side duct 174b. An outlet 230c of the relay duct 228c is connected with the outlet joint 184c. An inlet 229d of the relay duct 228d is connected with the outlet 182d of the side duct 174b. An outlet 230d of the relay duct 228d is connected with the outlet joint 184d.
An inlet 226a of the relay duct 225a is connected with the outlet 183a of the side duct 174a. An outlet 227a of the relay duct 225a is connected with an outlet joint 188a illustrated in
An inlet 226c of the relay duct 225c is connected with an outlet of a main body duct 179, which is on the right side, illustrated in
As illustrated in
As illustrated in
As illustrated in
In addition, the air flowing to the developing devices 1a to 1d collects scattered toner. In the image forming unit 700, toner images are formed by toner being supplied from the developing devices 1a to 1d to the photosensitive drums 3a to 3d. Part of the toner (referred to as scattered toner) supplied from the developing devices 1a to 1d is scattered without being adhered to the photosensitive drums 3a to 3d.
The toner is supplied to the photosensitive drum 3a by the upper sleeve 210a and the lower sleeve 211a; however, remaining toner not supplied to the photosensitive drum 3a is collected into the mixing chamber 240. However, part of the toner not supplied to the photosensitive drum 3a may be scattered out of the developing device 1a without being collected into the mixing chamber 240. The scattered toner may soil the inside of the image forming apparatus 100 and cause an image defect. Therefore, a toner collection unit for collecting the scattered toner using air may be provided.
As illustrated in
The collection duct 215a and the exhaust duct 217a are connected by a relay duct 216a. Air that includes scattered toner is discharged out of the image forming apparatus 100 from the collection duct 215a through the relay duct 216a and the exhaust duct 217a by an airflow generated by the exhaust fan 214a. The toner collection filter 218a is disposed in the exhaust duct 217a between the relay duct 216a and the exhaust fan 214a. Therefore, the toner is removed from the air when the air passes through the toner collection filter 218a, and the air from which the toner has been removed is discharged out of the image forming apparatus 100 from an exhaust port 296a. Regarding the airflow, the developing devices 1a to 1d have similar configurations. That is, the above description also describes the developing devices 1b to 1d if the letters at the end of the reference numerals are changed from a to b through d.
The filter 175a is held by the holder 175b. Therefore, the user or a person in charge of service can easily replace the filter 175a by removing the holder 175b from the intake port 175.
As illustrated in
There is a space between a bottom surface of the protruding portion 257 of the top surface cover 171 and a top surface of the left front door 170a. The intake ports 175 are connected with this space. The intake ports 175 take in air from this space and send the air to the intake unit 124.
The intake ports 175 are sufficiently spaced apart from an installation surface 1Z of the image forming apparatus 100. Therefore, the intake ports 175 do not easily suck in dust deposited on the installation surface 1Z. Therefore, dust is prevented from entering from outside of the first housing 101a into the image forming apparatus 100.
The intake ports 175 are provided on the bottom surface of the protruding portion 257 rather than on a front surface of the protruding portion 257. Thus, the intake ports 175 do not easily enter a field of view of an operator, and an aesthetic appearance of the image forming apparatus 100 is not easily spoiled. Furthermore, an operation sound of the image forming apparatus 100 from the intake ports 175 is less audible compared to a case where the intake ports 175 are on the front of the protruding portion 257.
Next, an airflow related to the chargers 2a and 2b supported in the first housing 101a will be described. Regarding an airflow of the chargers 2c and 2d, an intake port different from the intake ports 175 takes in air, and so a description thereof will be omitted.
The charger 2a generates not only ions but also ozone at the time of corona discharge. Ozone tends to corrode metals (e.g., grids made of stainless steel) and the like included in the charger 2a. Therefore, ozone needs to be collected. Thus, an ozone collection filter 219a for collecting ozone is provided (
The airflow from the intake ports 175 to the chargers 2a and 2b is as described with reference to
The primary exhaust duct 204a and the exhaust duct 217a are connected via a relay duct 223a. By an airflow generated by the exhaust fan 220a, air that includes ozone passes from the primary exhaust duct 204a through the relay duct 223a and the exhaust duct 217a and is discharged out of the image forming apparatus 100 from an exhaust port 297a. The ozone collection filter 219a is disposed in a path (e.g., the exhaust duct 217a) between the relay duct 223a and the exhaust fan 220a. Therefore, ozone is removed from the air when the air passes through the ozone collection filter 219a, and the air from which ozone has been removed is discharged out of the image forming apparatus 100.
<Fan Control>
The CPU 191 determines an open/closed state (protective state/non-protective state) of the left front door 170a based on the detection result of the door switch 192a. The CPU 191 determines the open/closed state (protective state/non-protective state) of the right front door 170b based on the detection result of the door switch 192b. The CPU 191 recognizes the respective temperatures of the developing devices 1a to 1d based on the detection results of the temperature sensors 193a to 193d. The CPU 191 determines an attached/detached state (protective state/non-protective state) of the cover 173 based on the detection result of the cover switch 194. A person in charge of maintenance can switch between a locked state and an unlocked state by rotating the lock lever 185. The cover switch 194 outputs a detection signal indicating that the cover 173 is in an attached state when the lock lever 185 is in the locked state.
In step S1401, the CPU 191 determines whether a print start has been instructed from the operation unit 200 or the like. When a print start is instructed, the CPU 191 advances the processing to step S1402.
In step S1402, the CPU 191 turns on the intake fans 177a to 177d.
In step S1403, the CPU 191 determines whether a front door (left front door 170a or right front door 170b) is open based on the detection result of the door switches 192a and 192b. A state in which the left front door 170a or the right front door 170b is closed corresponds to a protective state. A state in which the left front door 170a or the right front door 170b is open corresponds to a non-protective state. If at least one of the door switches 192a and 192b is open, the CPU 191 advances the processing to step S1404. Meanwhile, if both of the door switches 192a and 192b are closed, the CPU 191 advances the processing to step S1402.
In step S1404, the CPU 191 turns off (stops) the intake fans 177a to 177d. The rotation speed of the intake fans 177a to 177d may be lowered to be less than a prescribed rotation speed. The prescribed rotation speed may be determined, for example, based on an outside air temperature or based on an internal temperature of the image forming apparatus 100. For example, a lowered rotation speed is, for example, a rotation speed at which unfixed toner will not be sucked in.
There is unfixed toner on a surface of the sheet S removed from the conveyance unit 195. The intake fans 177a and 177b may suck in the unfixed toner from the intake ports 175 together with air. The unfixed toner sucked in from the intake ports 175 may adhere to the chargers 2a and 2b. This may reduce the charging performance of the chargers 2a and 2b and cause image defects. Therefore, when the left front door 170a or the right front door 170b is open, the CPU 191 stops the intake fans 177a and 177b. This reduces image defects caused by soiling of the chargers 2a and 2b.
The intake fans 177c and 177d may be kept on when the left front door 170a or the right front door 170b is open; however, they may be turned off along with the intake fans 177a and 177b. If the intake ports of the intake fans 177c and 177d are at positions (e.g., the lower surface of the protruding portion 257) at which unfixed toner is easily sucked in, the intake fans 177c and 177d operate in conjunction with the intake fans 177a and 177b. If the intake ports of the intake fans 177c and 177d are at positions (e.g., the back surface 253 or the right side surface 254) at which unfixed toner is not easily sucked in, the intake fans 177c and 177d may be controlled separately from the intake fans 177a and 177b. That is, the intake fans 177c and 177d may be kept on even when the left front door 170a or right front door 170b is open.
In step S1411, the CPU 191 determines whether a print start has been instructed from the operation unit 200 or the like. When a print start is instructed, the CPU 191 advances the processing to step S1412.
In step S1412, the CPU 191 measures a temperature T of the developing device 1a using the temperature sensor 193a.
In step S1413, the CPU 191 determines whether the temperature T is greater than or equal to a threshold temperature Th. If the temperature T is less than the threshold temperature Th, the CPU 191 advances the processing to step S1412. If the temperature T is greater than or equal to the threshold temperature Th, the CPU 191 advances the processing to step S1414.
In step S1414, the CPU 191 turns on the intake fan 180a for the developing device 1a. The developing device 1a is thus cooled.
In step S1415, the CPU 191 determines whether the cover unit 125 has been removed based on the detection result of the cover switch 194. If the cover unit 125 is attached to the image forming apparatus 100, the CPU 191 advances the processing to step S1414. If the cover unit 125 is detached from the image forming apparatus 100, the CPU 191 advances the processing to step S1416.
In step S1416, the CPU 191 turns off (stop) the intake fan 180a for the developing device 1a.
The intake fans 180a to 180d for the developing devices 1a to 1d may be controlled independently of the open/closed states of the left front door 170a and the right front door 170b. This is because it hardly becomes a problem even if unfixed toner sucked in from the intake ports 175 adheres to the developing devices 1a to 1d. Therefore, a priority is placed on controlling the intake fans 180a to 180d such that the temperatures of the developing devices 1a to 1d are a predetermined temperature.
Meanwhile, if the cover unit 125 is removed and maintenance is executed, the intake fans 180a to 180d may scatter the scattered toner deposited in the image forming units Pa to Pd. This is because volumes of air of the intake fans 180a to 180d are relatively large. Therefore, if the cover unit 125 is removed, the intake fans 180a to 180d are stopped.
The air taken in from the intake ports 175 with the operation of the intake fans 180a to 180d is sent to the developing devices 1a to 1d via the main body duct 174, the ducts 181a to 181d, and the relay ducts 228a to 228d, respectively. The developing devices 1a to 1d are thus appropriately cooled. However, this is only one example. For example, a group of components (e.g., the drum cleaning devices 4a to 4d) that constitute the image forming units Pa to Pd may be targets to be cooled by airflow. The control method described in
The air taken in from the intake ports 175 with the operation of the intake fans 177a and 177b is supplied to the chargers 2a and 2b through the main body duct 174, the ducts 178a and 178b, and the relay ducts 225a and 225b, respectively. However, this is only one example. The above-described airflow and the control method described in
As illustrated in
In
Although the intake fans 177a and 177b are controlled in the above-described control method, as illustrated in
Similarly, the exhaust fans 214a to 214d may be turned on/off in conjunction with the intake fans 180a to 180d. In other words, the intake fan 180a and the exhaust fan 214a may be turned on/off by the CPU 191 in conjunction with each other. The intake fan 180b and the exhaust fan 214b may be turned on/off by the CPU 191 in conjunction with each other. Furthermore, the intake fan 180c and the exhaust fan 214c may be turned on/off by the CPU 191 in conjunction with each other. Furthermore, the intake fan 180d and the exhaust fan 214d may be turned on/off by the CPU 191 in conjunction with each other.
[Item 1]
The first housing 101a and the second housing 101b are examples of a housing. The image forming units Pa to Pd are examples of an image forming unit. The photosensitive drums 3a to 3d are examples of a photosensitive body. The chargers 2a to 2d are examples of a charger. The exposure devices La to Ld are examples of an exposure device. The developing devices 1a to 1d are examples of a developing device. The primary transfer rollers 24a to 24d, the intermediate transfer belt 130, and the outer roller 11 are examples of a transfer roller. The left front door 170a, the right front door 170b, and the cover 173 are examples of a protective member. The main body duct 174, the side ducts 174a and 174b, the ducts 181a to 181d, the ducts 178a and 178b, the exhaust duct 217a, and the like are examples of a duct. The intake fans 180a to 180d, the intake fans 177a and 177b, the exhaust fan 214a, and the exhaust fan 220a are an example of one or more fans. The CPU 191 is an example of at least one processor. As described above, when the protective member is in a protective state, rotation of the at least one fan is permitted, and when the protective member is in a non-protective state, rotation of the at least one fan is restricted, thereby preventing the inside of the image forming apparatus from being soiled by unfixed toner.
[Item 2]
The chargers 2a to 2d, the post charger 1601, and the charge removing device 1602 are examples of an electrical component that generates ozone. The main body duct 174, the ducts 178a and 178b, the relay ducts 225a and 225b are examples of a first supply duct. The main body duct 174, the ducts 181a to 181d, the relay ducts 228a to 228d are examples of a second supply duct. The intake fans 177a and 177b are examples of a first fan. The intake fans 180a to 180d are examples of a second fan. As described above, a fan for supplying air to an electrical component that causes an image defect due to toner entering may be stopped. Meanwhile, control of a fan for supplying air to an electrical component that does not easily cause an image defect due to toner entering may be permitted.
[Item 3]
The left front door 170a and the right front door 170b are examples of a first protective member. The cover 173 is an example of a second protective member. The door switches 192a and 192b are examples of a first circuit element. The cover switch 194 is an example of a second circuit element. When the door switches 192a and 192b are detecting that the doors are closed, rotation may be permitted for the first fan. When the door switches 192a and 192b are detecting that the doors are open, rotation may be restricted for the first fan. When the cover switch 194 is detecting the protective state, rotation of the second fan may be allowed. When the cover switch 194 is detecting the non-protective state, rotation of the second fan may be restricted. The second fan need not depend on states of the door switches 192a and 192b and may depend on the cover switch 194 and a temperature of the developing device.
[Item 4]
If the charger becomes soiled by unfixed toner, an image defect may occur.
[Item 5]
If a charge removing device becomes soiled by unfixed toner, an image defect may occur.
[Item 6]
If a post charger becomes soiled by unfixed toner, an image defect may occur.
[Item 7]
A group of other components different from the electrical component includes the developing device. This is because even if toner adheres to the developing device, an image defect does not easily occur.
[Item 8]
The drum cleaning devices 4a to 4d are examples of a cleaning member. A belt cleaning device for cleaning the intermediate transfer belt 130 is also an example of the cleaning member.
[Item 9]
The door switches 192a and 192b and the cover switch 194 are examples of a circuit element. Both the intake fan and the exhaust fan may be controlled by the CPU 191 in conjunction with each other. Alternatively, the intake fan may be omitted, and the exhaust fan may be disposed. In that case, the CPU 191 may control the exhaust fan in place of the intake fan.
[Item 10]
The left front door 170a and the right front door 170b are examples of a cover or a door that can be opened and closed.
[Item 11]
The cover 173 is an example of a cover or a door that can be attached and detached.
[Item 12]
The protruding portion 257 is an example of a protruding portion that protrudes in a direction of the normal of a first side surface (e.g., the front surface 251). The intake ports 175 are examples an intake port disposed on a lower surface of the protruding portion. When the intake ports 175 thus face downward, toner is easily sucked in. Therefore, when the left front door 170a is open, intake from the intake ports 175 is restricted.
[Item 13]
The conveyance unit 195 is an example of a conveyance roller. Since the intake ports 175 are positioned above the conveyance unit 195, when the conveyance unit 195 is pulled out, unfixed toner on a sheet easily enters the intake ports 175. Therefore, when the left front door 170a is open, intake from the intake ports 175 is restricted.
[Item 14]
As described above, the conveyance unit 195 may be configured to be capable of being pulled out from the front surface 251. This prevents unfixed toner from entering from the intake ports 175 while making it easy to take out a jammed sheet.
[Item 15]
The back surface 253 is an example of a second side surface.
[Item 16]
As described above, a fan stops or the rotation speed of the fan decreases, thereby preventing unfixed toner from being sucked in.
[Item 17]
The intake fans 177a to 177d and the intake fans 180a to 180d, which are permitted to rotate by the CPU 191, may be controlled according to a temperature of the image forming unit.
[Item 18]
The main body duct 174 and the like are examples of an intake duct. The primary exhaust duct 204a and the exhaust duct 217a are examples of a first exhaust duct. The exhaust duct 217a and the like are examples of a second exhaust duct. The exhaust fan 220a is an example of a third fan. The exhaust fan 214a is an example of a fourth fan. When the protective member is in the protective state, the CPU 191 may permit rotation of the first fan, the second fan, the third fan, and the fourth fan. When the protective member is in the non-protective state, the CPU 191 may restrict rotation of the first fan and the third fan and permit rotation of the second fan and the fourth fan. For example, a plurality of fans disposed in a duct associated with the charger may be controlled according to the state of the protective member. For example, a plurality of fans disposed in a duct associated with the developing device may be controlled independent of the state of the protective member.
[Item 19]
The first exhaust duct may include a first filter disposed between the charger and the third fan. The second exhaust duct includes a second filter disposed between the group of other components and the fourth fan.
Upon detecting a pull out of the conveyance roller, the CPU 191 may restrict rotation of the at least one fan. In that case, the door switches 192a and 192b may be replaced with a sensor for detecting a pull out of the conveyance roller.
Embodiment(s) of the present invention can also be realized by a computer of a system or apparatus that reads out and executes computer executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be referred to more fully as a ‘non-transitory computer-readable storage medium’) to perform the functions of one or more of the above-described embodiment(s) and/or that includes one or more circuits (e.g., application specific integrated circuit (ASIC)) for performing the functions of one or more of the above-described embodiment(s), and by a method performed by the computer of the system or apparatus by, for example, reading out and executing the computer executable instructions from the storage medium to perform the functions of one or more of the above-described embodiment(s) and/or controlling the one or more circuits to perform the functions of one or more of the above-described embodiment(s). The computer may comprise one or more processors (e.g., central processing unit (CPU), micro processing unit (MPU)) and may include a network of separate computers or separate processors to read out and execute the computer executable instructions. The computer executable instructions may be provided to the computer, for example, from a network or the storage medium. The storage medium may include, for example, one or more of a hard disk, a random-access memory (RAM), a read only memory (ROM), a storage of distributed computing systems, an optical disk (such as a compact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™), a flash memory device, a memory card, and the like.
While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
This application claims the benefit of Japanese Patent Application No. 2022-170873, filed Oct. 25, 2022 which is hereby incorporated by reference herein in its entirety.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022-170873 | Oct 2022 | JP | national |
