Patent Application
20150110518
This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2013-218201 filed Oct. 21, 2013 and Japanese Patent Application No. 2014-061708 filed Mar. 25, 2014.
The present invention relates to a suction pipe, a suction device, and an image forming apparatus.
According to an aspect of the invention, there is provided a suction pipe including:
a suction port that has an opening shape which is long in one direction parallel with a longitudinal-direction part of an object structure long in one direction, and is arranged to face the longitudinal-direction part of the object structure to suction the air;
an exhaust port that has an opening shape which is different shape from the opening shape of the suction port, and suctions out the air suctioned from the suction port;
a flow path that connects the suction port and the exhaust port and has at least one bended portion which bends an air flow direction; and
at least one flow control members that are disposed at flow path in one direction parallel with the suction port, and controls a flow of the air.
Exemplary embodiments of the present invention will be described in detail based on the following figures, wherein:
Hereinafter, exemplary embodiments of the invention (simply referred to as “exemplary embodiments”) will be described with reference to the accompanying drawings.
An image forming apparatus 1 according to the first exemplary embodiment is configured, for example, as a color printer. As illustrated in
The imaging units 10 are configured as four imaging units 10Y, 10M, 10C, and 10K that are dedicated to form the toner images of the four respective colors of yellow (Y), magenta (M), cyan (C), and black (K). The four imaging units 10 (Y, M, C, and K) are arranged in a serially aligned state in an internal space of the housing 100. The respective imaging units 10 (Y, M, C, and K) have a configuration substantially common to one another as described below.
Each of the imaging units 10 (Y, M, C, and K) is configured by using, for example, known electrophotography, and has a photoconductive drum 11 that rotates in a direction illustrated with the arrow (clockwise direction in the drawing) as illustrated in
The main devices are charging devices 12 that charge image holding surfaces (outer circumferential surfaces) of the photoconductive drums 11, where the images may be formed, with a required potential, exposure devices 13 (Y, M, C, and K) that form electrostatic latent images (of the respective colors) with potential differences by irradiating the charged outer circumferential surfaces of the photoconductive drums 11 with light based on image information (signal), developing devices 14 (Y, M, C, and K) that turn the electrostatic latent images into the toner images, which are visible images, by developing the electrostatic latent images with the toner as the developers for the corresponding colors (Y, M, C, and K), charge adjusting corona dischargers 16 that primary image-transfer the toner images to (an intermediate image transfer belt of) the intermediate image transfer unit 20 and then adjust the charged states with adhered materials such as the toner, which remain to adhere to the image holding surfaces of the photoconductive drums 11, included, drum cleaning devices 17 that remove the adhered materials such as the toner, which pass through the charge adjusting corona dischargers 16 and adhere to the image holding surfaces of the photoconductive drums 11 to clean the surface, charge removers 18 that erase the image holding surfaces of the photoconductive drums 11 after the cleaning, and the like.
In the photoconductive drum 11, the image holding surface that has a photoconductive layer (photosensitive layer) formed of a photosensitive material is formed on a circumferential surface of a cylindrical or columnar base material which is grounded. The photoconductive drum 11 rotates in the direction illustrated with the arrow in response to power from a rotation driving device (not illustrated). The charging device 12 is a non-contact type charging device that applies charging bias to a discharge wire, which is arranged at required gaps on the image holding surface of the photoconductive drum 11, to charge the wire through corona discharge. A so-called scorotron type corona discharger, in which two discharge wires 12b and 12c are stretched in a container type shield case (covering member) 12a that is long along an axial direction of the photoconductive drum 11 and a charge adjusting material is arranged in an opening portion of the shield case 12a that faces the photoconductive drum 11, is used as the charging device 12 according to the first exemplary embodiment. A voltage or a current that has the same polarity as a charge polarity of the toner which is supplied from the developing device is supplied as the charging bias when the developing device 14 is a developing device that performs reversal development.
The exposure devices 13 (Y, M, C, and K) form the electrostatic latent images by irradiating the charged image holding surfaces of the photoconductive drums 11 with light beams Bm (dotted lines with the arrows) that are configured according to the image information input into the image forming apparatus 1. A non-scanning type exposure device that is configured by using a light-emitting diode, an optical component, and the like, and a scanning type exposure device that is configured by using an optical component such as semiconductor laser and a polygon mirror are used as the exposure device 13. The developing devices 14 (Y, M, C, and K) use a two-component developer that contains the toner, a carrier, and the like. As illustrated in
As illustrated in
The drum cleaning device 17 is configured to have a container-shaped housing 17a, a rotating brush 17b that rotates in a state where hair material is in contact with the outer circumferential surface of the photoconductive drum 11 after the primary image transfer, a cleaning plate 17c that is arranged to come into contact, at a required pressure, with a position on a further downstream side in the rotation direction than a contact portion of the rotating brush 17b on the outer circumferential surface of the photoconductive drum 11 to scrape the adhered material such as the toner that remains to adhere, a flicker 17d that scrapes off the adhered material such as the toner that adheres to the hair material of the rotating brush 17b, a recovery transport member 17e such as a screw auger that recovers the toner or the like which is scraped off from the hair material of the rotating brush 17b and transports the toner or the like to a recovery system (not illustrated). A plate-shaped member formed of flexible rubber, a resin, or the like is used as the cleaning plate 17c.
As illustrated in
Among the plural support rollers 22a to 22e and a support roller 22f that support the intermediate image transfer belt 21, the support roller 22a is configured as a driving roller, the support roller 22c is configured as a tensioning roller, and the support roller 22e is configured as a secondary image transfer auxiliary roller. The primary image transfer devices 23 is a contact type transfer device that rotates in contact with the inner surface of the intermediate image transfer belt 21 and has a primary image transfer roller to which primary image-transferring bias is supplied. A direct-current voltage that shows the polarity opposite to the charge polarity of the developer or the like is supplied as the primary image-transferring bias. The secondary image transfer device 25 is a contact type transfer device that rotates in contact with the outer surface of the intermediate image transfer belt 21 and has a secondary image transfer roller to which secondary image-transferring bias is supplied. A direct-current voltage that shows the polarity opposite to the charge polarity of the developer or the like is supplied as the secondary image-transferring bias. The belt cleaning device 26 has substantially the same configuration as the drum cleaning devices 17. In
The sheet feeding device 30 is arranged to be present at a position on a further downstream side than the intermediate image transfer unit 20. The sheet feeding device 30 is configured mainly of a single (or plural) sheet accommodating body 31 in which the recording sheets 9 of desired size, type, and the like are accommodated in a stacked state, and a feed device 32 that feeds the recording sheets 9 from the sheet accommodating body 31 sheet by sheet. A heating rotating body 42 that rotates in the direction illustrated with the arrow and is heated by a heating unit such that a surface temperature is maintained at a predetermined temperature, and a pressurizing rotating body 43 that is driven to rotate, in contact at a predetermined pressure, in a state of substantially along with the axial direction of the heating rotating body 42 are arranged in a housing 41 of the fixing device 40.
In addition, in the housing 100 of the image forming apparatus 1, a supply transport path, which is configured to have plural sheet transport roller pairs 33a, 33b, 33c, . . . and a transport guide material, is disposed between the sheet feeding device 30 and the secondary image transfer position of the intermediate image transfer unit 20 (part where the intermediate image transfer belt 21 and the secondary image transfer device 25 come into contact with each other). In addition, a sheet transport device 34 of belt type or the like, which transports the recording sheet 9 after the secondary image transfer to the fixing device 40, is installed between the secondary image transfer device 25 and the fixing device 40. Further, a discharge transport path, which is configured to have plural transport roller pairs 45a and 45b and a transport guide material, is disposed on a discharge side of the fixing device 40. Furthermore, a discharge accommodating section (not illustrated), which accommodates the recording sheet 9 that is discharged from the discharge transport path after the image formation, is disposed at a site out of the housing 100 or the like.
The image formation by the image forming apparatus 1 is performed in the following manner. Herein, a basic image forming operation is described as an example, in which a full color image is formed on one surface of the recording sheet 9 through a combination of the toner of the above-described four colors (Y, M, C, and K).
In the image forming apparatus 1, the respective photoconductive drums 11 of the four imaging units 10 (Y, M, C, and K) rotate in the arrow direction first when there is an instruction of a demand for initiation of the image forming operation (printing), and the charging devices 12 charge the image holding surfaces of the respective photoconductive drums 11 with the required polarity and potential. Then, the exposure devices 13 perform exposure by irradiating the charged image holding surfaces of the photoconductive drums 11 with the light beams Bm, which are emitted based on the image data decomposed into each color component (Y, M, C, and K) sent from an image processing apparatus (not illustrated), such that the electrostatic latent images of the respective color components which have the required potential differences are formed. Then, the respective developing devices 14 (Y, M, C, and K) supply the two-component developers of the respective colors (Y, M, C, and K) charged with the required polarity to the electrostatic latent images of the respective color components formed on the respective photoconductive drums 11 so as to make the toner electrostatically adhere to the electrostatic latent images. In this manner, any one of the toner images of the four colors (Y, M, C, and K) is formed on the image holding surface of the photoconductive drum 11 of each of the photoconductive drums 11.
Next, the toner images of the respective colors that are formed on the photoconductive drums 11 of the respective imaging units 10 (Y, M, C, and K) are primary image-transferred, by the respective primary image transfer devices 23 of the intermediate image transfer unit 20, to be sequentially superposed on the outer surface of the intermediate image transfer belt 21 rotating in the arrow direction. After the completion of the primary image transfer, the photoconductive drums 11 are adjusted, with the corona discharge by the charge adjusting corona dischargers 16, to a charged potential at which the potential of the adhered material remaining on the image holding surface and the potential of the image holding surface are likely to be cleaned (facilitating the removal of the adhered material). In addition, after passing through the charge adjusting corona dischargers 16, the photoconductive drums 11 are cleaned by the drum cleaning devices 17 and then the image holding surfaces are erased by the charge removers 18 such that the subsequent image forming process is prepared.
Subsequently, in the intermediate image transfer unit 20, the toner images that are primary image-transferred onto the intermediate image transfer belt 21 are held and transported to the secondary image transfer position, and then the toner images on the intermediate image transfer belt 21 are secondary image-transferred in a lump by the secondary image transfer device 25 at the secondary image transfer position onto the recording sheets 9 which are transported through the supply transport path from the sheet feeding device 30. After the completion of the secondary image transfer, the outer surface of the intermediate image transfer belt 21 is cleaned by the belt cleaning device 26 such that the subsequent intermediate image transfer process is prepared.
Lastly, the recording sheets 9 where the toner images are secondary image-transferred are separated from the intermediate image transfer belt 21 and then are transported by the sheet transport device 34 to be introduced into the fixing device 40. Then, the toner images are fixed through required fixing processing (heating and pressurization) in the fixing device 40. When the image formation is performed only on the one surface during the image forming operation, the recording sheet 9 is discharged out of the housing 100 through the discharge transport path and is accommodated in the discharge accommodating section after the completion of the fixing.
In the image forming apparatus 1, the recording sheet 9 where the full color image, which is formed through the combination of the toner images of the four above-described colors (Y, M, C, and K), is formed is output through the operation described above. When there is an instruction for the image forming operation for plural sheets, a series of the above-described operations are repeated in the same manner to match the number of the sheets.
In the image forming apparatus 1, ozone and corona products that are generated through the corona discharge by the charge adjusting corona dischargers 16 adhere to and accumulate on the photoconductive drums 11 and cause an image defect (mainly uneven concentration). The suction device 5 that suctions the air which is present in and in the vicinity of the shield case 16a of the charge adjusting corona dischargers 16 along with the ozone and the corona products is installed, as illustrated in
In the image forming apparatus 1, the ozone and the corona products that are generated through the corona discharge in the charging devices 12 adhere to and accumulate on the discharge wires 12b and 12c and the photoconductive drums 11 and cause a charge failure (mainly uneven charging) and an image defect (mainly uneven image quality). In order to prevent this, air (arrow with the two-dot chain line) that is blown from a blower device (not illustrated) is sprayed into the shield case 12a of the charging devices 12 as illustrated in
In addition, in the image forming apparatus 1, suction devices 80A and 80B that respectively suction and capture the ozone and the corona products of the air, which is present on both sites on the upstream side and the downstream side in the rotation direction across the developing devices 14 of the photoconductive drums 11, and the waste toner are arranged, as illustrated in
The suction device 80A has a first suction duct 81 that has a first suction port 82 which faces a site between the charging device 12 and the developing device 14 on the image holding surface of the photoconductive drum 11, and a second suction duct 83 that has a second suction port 84 which faces a site of the photoconductive drum 11 between the first suction port 82 and the developing device 14, the first suction duct 81 and the second suction duct 83 being combined with each other, and exhaust ports of the respective suction ducts 81 and 83 are configured as a common exhaust port 85. In addition, the common exhaust port 85 is connected to a suction unit such as a suction fan (not illustrated) by piping. The suction device 80A suctions the ozone and the corona products that are discharged from the charging devices 12 from the first suction port 82 to the first suction duct 81 as is illustrated with the arrow with the two-dot chain line, suctions the floating or leaking toner from the second suction port 84 to the second suction duct 83 as is illustrated with the arrow with the two-dot chain line, and discharges the air or the like that is suctioned to the respective suction ducts 81 and 83 from the common exhaust port 85.
In addition, the suction device 80B has a third suction duct 86 that has a third suction port 87 which faces the site of the image holding surface of the photoconductive drum 11 until reaching the primary image transfer position after passing through the developing devices 14, and the third suction port 87 of the third suction duct 86 is connected to a suction unit (not illustrated) by piping. The suction device 80B suctions the waste toner leaking from the developing devices 14 and the like from the third suction port 87 to the third suction duct 86 as is illustrated with the arrow with the two-dot chain line and discharges the air or the like that is suctioned to the third suction duct 86 from the third suction port 87.
The ozone, the corona products, the toner, and the like that are discharged from the common exhaust port 85 and the exhaust port 87 are captured by capturing units such as filters which are respectively arranged at a site midway to the suction unit or at a site passing therethrough. The suction unit of the two suction devices 80A and 80B are combined, for example, into one.
Hereinafter, the suction device 5 will be described.
As illustrated in
The suction machine 50 is driving-controlled to suction a required amount of air. Examples of the suction machine 50 include a centrifugal blower such as a sirocco fan and various blowers such as a cross flow fan and an axial flow blower. In addition, the suction machine 50 is structured to release the air or the like that is suctioned out of the housing 100 of the image forming apparatus 1. Furthermore, the capturing unit such as the filter is arranged at a suction side position, at an exhaust side position, or at both of the positions of the suction machine 50 so as to capture a waste material which is mixed with the suctioned air.
As illustrated in
As illustrated in
The exhaust port 53 is disposed in one end portion of the exhaust flow path 54A which is open and the other end portion of the exhaust flow path 54A is closed. The exhaust flow path 54A, as a whole, is a flow path with a rectangular cylinder shape that is formed to extend along the longitudinal direction B of the charge adjusting corona discharger 16. The first bent flow path 54B is a cylindrical flow path that is formed to extend, bent at a substantially right angle, substantially downward (direction substantially parallel to a coordinate axis Y) from the other end portion-sided site (midway) of the exhaust flow path 54A in a state where the width of the flow path space 54a is increased. The second bent flow path 54C is a cylindrical flow path that is formed to extend, bent in a horizontal direction (direction substantially parallel to a coordinate axis X), from one end portion of the first bent flow path 54B toward the charge adjusting corona discharger 16 in a state where the width of the flow path space remains unchanged.
The widths (dimensions along the longitudinal direction B) of the flow path spaces 54a of the respective first bent flow path 54B and the second bent flow path 54C are set to be substantially equal to each other. In addition, the suction port 52 is formed in a terminal end portion of the second bent flow path 54C. The suction port 52 is formed as an opening with an oblong opening shape that is slightly narrower than the cross-sectional shape of the flow path space of the one end portion (terminal end portion) of the second bent flow path 54C (Still, the length of the suction port 52 in the longitudinal direction is substantially equal to the width of the second bent flow path 54C).
The suction port 52 of the suction duct 51 is formed to have a long opening shape (for example, an oblong shape) that is parallel to a part (opening 16d) of the charge adjusting corona discharger 16 in the longitudinal direction B. The exhaust port 53 is formed to have a substantially square opening shape. A connection duct 55 that is connected to the suction machine 50, exerts a suction force of the suction machine 50, and suctions out the air from the exhaust port 53 is connected to the exhaust port 53 (
Accordingly, the suction duct 51 has a relationship in which the suction port 52 and the exhaust port 53 are formed to have different opening shapes. However, even when the suction port 52 and the exhaust port 53 have the same shape, the relationship in which the opening shares differ from each other is satisfied if the suction port 52 and the exhaust port 53 are formed to have different opening areas (similarity shapes). In addition, as illustrated in
In the suction duct 51 that has the suction port 52 and the exhaust port 53 which have different opening shapes, apart where the cross-sectional shape of the flow path space 54a is changed midway is present in the flow path 54 that connects the suction port 52 and the exhaust port 53 with each other.
In the suction duct 51 according to the first exemplary embodiment, the suction port 52 has an oblong opening shape whereas the exhaust port 53 has a square opening shape, which differ from each other, and thus bent parts (in actuality, the first bent flow path 54B and the second bent flow path 54C) are present in (the flow path space 54a of) the flow path 54. As a result, in the suction duct 51, particularly the flow path space 54a of the exhaust flow path 54A has a substantially square cross-sectional shape whereas the flow path space 54a of the first bent flow path 54B and the second bent flow path 54C is changed to a substantially oblong cross-sectional shape (without any change in height) which widens only in a substantially horizontal direction. In other words, the cross-sectional shape of the flow path space 54a of the first bent flow path 54B and the second bent flow path 54C is the cross-sectional shape of the flow path space 54a that is rapidly widened in the substantially horizontal direction with respect to the exhaust flow path 54A.
However, in the suction duct 51 where the part with the changed cross-sectional shape of the flow path space 54a is present, disturbance such as separation and a vortex is generated in air flow at the part where the cross-sectional shape changes. Accordingly, in the suction duct 51, the wind speed of the air that is suctioned from the suction port 52 tends to become non-uniform even when the air is emitted from the exhaust port 53 at a uniform wind speed. In actuality, the wind speed tends to be high at a site (one end portion or the like) of the suction port 52 that is on a side close to the exhaust port 53, and the wind speed at the other sites tends to be low (refer to
The above-described tendency of the wind speed of the air suctioned by the suction port 52 becoming non-uniform in the end occurs in substantially the same manner when an air flow (travel) direction in the suction duct 51 changes, that is, when the flow path space 54a has a bent shape midway regardless of the presence or absence of a change in the cross-sectional shape of the flow path space 54a. Furthermore, the tendency of the wind speed of the air suctioned by the suction port 52 becoming non-uniform in the end occurs more considerably when the cross-sectional shape of the flow path space 54a changes and the air flow (travel) direction changes in addition thereto.
As illustrated in
Of the two flow control members 61 and 62, the flow control member 61 is an “uppermost stream flow control member” that is disposed at an upstream side site of the flow path space 54a of the flow path 54 in the air flow direction in a state of being blocked by a permeable member 70. In the first exemplary embodiment, the upstream side site is the suction port 52 that is the uppermost stream site.
The permeable member 70 is a member which has, for example, plural ventilation portions 71. As illustrated in
The permeable member 70 may be formed to be integrally molded with the suction duct 51 by using the same material or may be formed by using a different material from the material of the suction duct 51. The opening shape, the opening dimension, the hole length, and the density of the presence of the hole of the ventilation portion (hole) 71 are selectively set from the viewpoint of uniformizing the wind speed of the air suctioned through the suction port 52 as much as possible. In addition, these values are set allowing for the dimension (capacity) of the suction duct 51 and the flow amount of the air per unit time to be suctioned by the suction duct 51 or suctioned from the charge adjusting corona discharger 16.
Of the two flow control members 61 and 62, the other flow control member 62 is a “lowermost stream flow control member” that is disposed at a required site of the first bent flow path 54B, as illustrated in
The lowermost stream flow control member 62 is configured by arranging a plate-shaped blocking member 64 in a crossing state with the gap 63 with respect to a one side surface of the cross-sectional shape of the flow path space 54a in the flow path space 54a of the first bent flow path 54B without changing the appearance of the first bent flow path 54B. Specifically, the blocking member 64 blocks one side wall surface part of the cross-sectional shape of the flow path space 54a of the first bent flow path 54B in a crossing state as illustrated in
The height H, the path length M, and the width (length of the longitudinal direction B) W of the gap 63 that constitutes the lowermost stream flow control member 62 are selectively set from the viewpoint of uniformizing the wind speed of the air flowing from the second bent flow path 54C into the first bent flow path 54B as much as possible and causing the air to flow to the exhaust flow path 54A. In addition, these values are set allowing for the dimension (capacity) of the suction duct 51 and the flow amount of the air per unit time suctioned by the suction duct 51 or suctioned from the charge adjusting corona discharger 16.
Hereinafter, an operation of the suction device 5 will be described.
The suction device 5 suctions a required volume of air first, with the suction machine 50 being driven to rotate, during a driving setting period such as during the image forming operation. When the suction machine 50 is ignited, an operation for suctioning and discharging air (E200) is initiated in the suction machine 50 as illustrated in
In this case, air (E2) that is present in the flow path space 54a of the exhaust flow path 54A of the suction duct 51 is suctioned out from the exhaust port 53 first due to the suction force of the suction machine 50. In this manner, the air (E2) that is present in the flow path space 54a of the exhaust flow path 54A flows substantially along a direction R1 in which the air in the flow path space 54a should flow. Lastly, the air (E2) passes through the exhaust port 53 as air (E1), which is settled in the front of the exhaust port 53, and flows out to the connection duct 55. When the air is suctioned out from the exhaust port 53 in this manner, the suction force of the suction machine 50 is exerted in the flow path space 54a of the exhaust flow path 54A.
Then, air (E3) that is present in the flow path space 54a of the first bent flow path 54B is suctioned and moved into the flow path space 54a of the exhaust flow path 54A due to the suction force of the suction machine 50 exerting in the flow path space 54a of the exhaust flow path 54A. In this case, the air (E3) passes through the gap 63 of the lowermost stream flow control member 62 in the flow path space 54a of the first bent flow path 54B as illustrated in
In this case, the air (E3) that is present in the flow path space 54a of the first bent flow path 54B flows along an air flow direction R2 of the flow path space 54a, but the traveling of a part thereof is blocked by the blocking member 64 of the lowermost stream flow control member 62 and the other part is in a controlled state (state where the pressure is raised) after passing through the elongated and narrow gap 63 of the lowermost stream flow control member 62 to flow into the flow path space 54a of the exhaust flow path 54A from the gap 63.
In this manner, the air (E3) that is suctioned and flows from the first bent flow path 54B to the exhaust flow path 54A tends to flow as air (E3a), which is extremely leaned state, after almost passing through an area in an end portion on a side close to the exhaust port 53 (in actuality, the suction machine 50) of the first bent flow path 54B (refer to
Lastly, air (E5) that is present out of the suction port 52 is suctioned into the flow path space 54a of the second bent flow path 54C through the suction port 52 due to the suction force of the suction machine 50 which is exerted in the flow path space 54a of the first bent flow path 54B and the second bent flow path 54C. In this case, the air (E5) passes through the permeable member 70 that constitutes the uppermost stream flow control member 61 which is disposed in the suction port 52 and flows into the flow path space 54a of the second bent flow path 54C. Herein, the air (E5) is present in the connection duct 56 between the suction duct 51 and the charge adjusting corona discharger 16 in the first exemplary embodiment. However, in actuality, the air (E5) is air that is present in and in the vicinity of the shield case 16a of the charge adjusting corona discharger 16.
In this case, the air (E5) that is present out of the suction port 52 is suctioned from the suction port 52 of the suction duct 51. However, in this case, the air (E5) passes through the plural ventilation portions (holes) 71 of the permeable member 70 that constitutes the uppermost stream flow control member 61 and flows into the flow path space 54a of the second bent flow path 54C. When the air is suctioned from the suction port 52 in this manner, the suction force of the suction machine 50 is exerted out of the suction port 52.
In this manner, the air (E5) that is suctioned from the suction port 52 passes through the plural ventilation portions 71 of the permeable member 70 with a relatively narrower opening area than the opening area of the suction port 52 to be suctioned in a state where the flow is controlled (in a state where the pressure is raised also in this case).
In addition, the air (E5) that is suctioned from the suction port 52 passes through the plural ventilation portions 71 that are dotted over the entire opening area of the suction port 52 and formed under the same conditions, and thus becomes uniform from the area substantially close to the opening shape of the suction port 52 and is in an environment where the air (E5) is suctioned from the suction port 52. However, in actuality, the speed of the air (E3a) that passes through the area of an end portion 63a of the gap 63 on the side close to the exhaust port 53 becomes the fastest in the air (E3) at a time of flowing to pass through the gap of the lowermost stream flow control member 62 due to the suction force of the suction machine 50 in the longitudinal direction B of the suction port 52 as illustrated in
The air (E5) suctioned from the suction port 52 as described above passes through the plural ventilation portions 71 of the permeable member 70 of the uppermost stream flow control member 61 to be suctioned with the traveling direction thereof aligned in the direction substantially orthogonal to the longitudinal direction B of the suction port 52, and the air suction velocity in the longitudinal direction B of the suction port 52 is controlled to be considerably different. In addition, the wind speed of the air (E5) suctioned from the suction port 52 is controlled to be considerably different in the longitudinal direction B of the opening shape (oblong shape) of the suction port 52 and is controlled to be considerably different in the lateral direction C (refer to
As illustrated in
The suction force of the air (E5) in the suction port 52 of the suction duct 51 is exerted also in the shield case 16a of the charge adjusting corona discharger 16 and the opening 16b thereof via the connection duct 56. In this manner, the air that is present in the shield case 16a of the charge adjusting corona discharger 16 and the air that is present in the vicinity of the opening 16b are suctioned from the suction port 52 of the suction duct 51.
In this case, the suction of the air in the suction port 52 of the suction duct 51 is allowed such that the suction of the air with little unevenness in the longitudinal direction B of the suction port 52 since the air suction velocity in the longitudinal direction B of the suction port 52 is controlled not to be considerably different, and thus the air (E5) that is present in the shield case 16a of the charge adjusting corona discharger 16 is also suctioned in the suction duct 51 at the substantially same speed in the longitudinal direction B of the shield case 16a.
In this manner, during the operation of the charge adjusting corona discharger 16, the ozone and the corona products that are generated in and in the vicinity of the shield case 16a are suctioned substantially uniformly along with the air (E5) in the longitudinal direction B of the shield case 16a. Accordingly, in the imaging units 10 (Y, M, C, and K) in which the suction device 5 is installed, the generation of defects of the image quality such as concentration unevenness due to, for example, the suction of the air by the suction device performed extremely leaned in the axial direction of the photoconductive drum 11, which causes the ozone and the corona products that are generated in the charge adjusting corona discharger 16 adhere and accumulate in a state of being leaned in the axial direction of the image holding surface of the photoconductive drum 11 corresponding to the side where the suction of the air by the suction device is relatively weak, may be controlled.
The simulation is performed on the assumption of the following conditions, in which the suction duct 51 has an overall shape which is illustrated in
The suction duct 51 having the suction port 52 with an oblong opening shape of 17.5 mm×350 mm and the exhaust port 53 with a substantially square opening shape of 22 mm×23 mm is used as the suction duct. A polyhedral mesh as the permeable member 70, which is disposed on condition that the ventilation portion 71 with a hole diameter of 0.3 mm and a length of 3 mm is disposed at a density of 0.42 units/mm2 units/cm2) is used as the uppermost stream flow control member 61. The lowermost stream flow control member 62 is configured to have a path length M of 8 mm and a width W of 345 mm, with the height H of the gap 63 being 1.5 mm on average, at a site having a position shifted by a dimension N=6 mm (
In addition, the simulation assumes that the air with a volume at which the average wind speed of the air suctioned out from the exhaust port 53 of the suction duct 51 is approximately 10 m per second is suctioned from the suction machine 50, and the wind speed of the suction port 52 in the longitudinal direction B in this case is measured. As illustrated in
In the graph of
For reference, the simulation is performed in the same manner assuming the suction duct (comparative example) 510X in general used in a suction device of the related art as illustrated in
The suction duct 510X has an overall shape that is illustrated in
As is apparent in the result illustrated in
In contrast, as is apparent in the result illustrated in
The suction device 5B has the same configuration as the suction device 5 according to the first exemplary embodiment except that the suction device (5B) is changed to use the suction duct 51B, which has a partially different configuration. As illustrated in
The first bent flow path 54D of the suction duct 51B is changed such that a part on an upstream side of the flow path space 54a in the air flow direction R2 is shaped to have a gradually decreasing height toward the downstream side. In addition, the second bent flow path 54E of the suction duct 51B is changed to be formed to extend toward the charge adjusting corona discharger 16, bent in a substantially horizontal direction, from a site (side surface portion) that is a substantially middle point of the first bent flow path 54D in the air flow direction R2 in a state where the width of the flow path space 54a (dimension along the longitudinal direction B) remains unchanged and to have the suction port 52, which has the substantially same opening shape (oblong shape) as the cross-sectional shape of the flow path space 54a of the terminal end portion, formed at a terminal end portion of the second bent flow path 54E.
In addition, the third flow control member (middle flow control member) 65 is disposed at a site between the uppermost stream flow control member 61 and the lowermost stream flow control member 62 in the air flow direction of the flow path space 54a. Specifically, the third flow control member 65 is disposed at a site on a downstream side in the air flow direction of the flow path space 54a of the second bent flow path 54E. In addition, the middle flow control member 65 is configured to be shaped to have an elongated and oblong gap 66 that extends in a direction which is parallel to the longitudinal direction B of the opening shape of the suction port 52.
The middle flow control member 65 of the second exemplary embodiment is changed in shape to squeeze the appearance of the second bent flow path 54E and is configured to be formed to have a shape with which the gap (narrow path) 66, which is in a narrowed state in a substantially central portion of the flow path space 54a of the second bent flow path 54E, is present. In addition, the height H, the path length M, and the width W of the gap 66 are selectively set from the viewpoint of uniformizing the wind speed of the air flowing from the first bent flow path 54D to the second bent flow path 54E as much as possible substantially as in the case of the gap 63 of the lowermost stream flow control member 62, and are set allowing for the dimension (capacity) of the suction duct 51B and the flow amount of the air per unit time which should be suctioned out from the entire flow path space 54a of the suction duct 51B or the charge adjusting corona discharger 16.
Hereinafter, an operation of the suction device (5B) will be described.
In this suction device, the air suction force that is generated through the operation of the suction machine 50 is exerted in the suction duct 51 through the connection duct 55, and the suction of the air (E200) is initiated in the suction port 52 in the suction duct 51B.
In this case, the air (E2) that is present in the flow path space 54a of the exhaust flow path 54A of the suction duct 51B is suctioned out from the exhaust port 53 due to the suction force of the suction machine 50 as in the case with the suction duct 51 according to the first exemplary embodiment. In this manner, the air (E2) that is present in the flow path space 54a of the exhaust flow path 54A passes through the exhaust port 53 in the end as the air (E1), which is settled in the front of the exhaust port 53, and flows out to the connection duct 55. When the air (E2) is suctioned out from the exhaust port 53 in this manner, the suction force of the suction machine 50 is exerted in the flow path space 54a of the exhaust flow path 54A.
Then, the air (E3) that is present in the flow path space 54a of the first bent flow path 54D is suctioned and moved into the flow path space 54a of the exhaust flow path 54A due to the suction force of the suction machine 50 exerting in the flow path space 54a of the exhaust flow path 54A. In this case, the air (E3) passes through the gap 63 of the lowermost stream flow control member 62 in the flow path space 54a of the first bent flow path 54D as illustrated in
In this case, the air (E3) that is present in the flow path space 54a of the first bent flow path 54D flows along the air flow direction R2 of the flow path space 54a, but the traveling of a part thereof is blocked by the blocking member 64 of the lowermost stream flow control member 62 and the other part is in a controlled state (state where the pressure is raised) after passing through the elongated and narrow gap 63 of the lowermost stream flow control member 62 to flow into the flow path space 54a of the exhaust flow path 54A from the gap 63.
In this manner, also in the suction duct 51B, a large amount of the air (E3b and E3c) that passes also through the area to the end portion on the side opposite to the area of the end portion on the side close to the exhaust port 53 of the first bent flow path 54D is present (refer to
Subsequently, air (E7) that is present in the flow path space 54a of the second bent flow path 54E is suctioned and moved into the flow path space 54a of the first bent flow path 54D due to the suction force of the suction machine 50 which is exerted in the flow path space 54a of the first bent flow path 54D. In this case, the air (E7) passes through the gap 66 of the middle flow control member 65 in the flow path space 54a of the second bent flow path 54E as illustrated in
In this case, the air (E7) that is present in the flow path space 54a of the second bent flow path 54E flows along the air flow direction R2 of the flow path space 54a, but flows into the flow path space 54a of the first bent flow path 54D from the gap 66 in a state of being controlled after passing through the elongated and narrow gap 66 of the middle flow control member 65 (state where the pressure is raised). When the air (E7) passes through the gap 66 of the middle flow control member 65, the suction force of the suction machine 50 is exerted in the flow path space 54a of the second bent flow path 54E.
In this manner, also in the suction duct 51B, a large amount of air (E7b and E7c) that passes also through the area to the end portion on the side opposite to the area of the end portion on the side close to the exhaust port 53 of the second bent flow path 54E is present as in the case, of the suction duct 51 according to the first exemplary embodiment. In addition, the air (E7) that flows into the flow path space 54a of the first bent flow path 54D stays in a temporarily circulating state in the flow path space 54a of the second bent flow path 54E and in the flow path space 54a of the first bent flow path 54D with larger in volume than the space of the gap 66. In this manner, the air (E7) that is suctioned with the speed difference in the longitudinal direction B of the flow path space 54a of the first bent flow path 54D is mixed due to the temporary circulating stay as is the case with the air (E6) and, as a result, the speed difference is alleviated and is cancelled to some extent.
Lastly, air (E8) that is present out of the suction port 52 is suctioned into the flow path space 54a of the second bent flow path 54E through the suction port 52 of the suction duct 51B due to the suction force of the suction machine 50 which is exerted in the flow path space 54a of the second bent flow path 54E. In this case, the air (E8) passes through the permeable member 70 that constitutes the uppermost stream flow control member 61 which is disposed in the suction port 52 and flows into the flow path space 54a of the second bent flow path 54C.
In this case, the air (E8) that is present out of the suction port 52 is suctioned from the suction port 52 of the suction duct 51B. However, in this case, the air (E8) passes through the plural ventilation portions (holes) 71 of the permeable member 70 that constitutes the uppermost stream flow control member 61 and flows into the passing space 54a of the second bent flow path 54E. When the air is suctioned in the suction port 52 in this manner, the suction force of the suction machine 50 is exerted out of the suction port 52.
In this manner, the air (E8) that is suctioned from the suction port 52 of the suction duct 51B passes through the plural ventilation portions 71 of the permeable member 70 with a relatively narrower opening area than the opening area of the suction port 52 to be suctioned in a state where the flow is controlled (in a state where the pressure is raised also in this case).
In addition, the air (E8) that is suctioned from the suction port 52 of the suction duct 51B passes through the plural ventilation portions 71 that are dotted over the entire opening area of the suction port 52 and formed under the same conditions, and thus becomes uniform from the area substantially close to the opening shape of the suction port 52 and is in an environment where the air (E8) is suctioned from the suction port 52. However, in actuality, the speed of the air (E3a and the like) that passes through the area of the end portions 63a and 66a on the sides of the gaps 63 and 66 close to the exhaust port 53 becomes the fastest in the air (E3 and E7) at a time of flowing to pass through the gap 63 of the lowermost stream flow control member 62 and the gap 66 of the middle flow control member 65 due to the suction force of the suction machine 50 in the longitudinal direction B of the suction port 52, and the speed of the air (E3b and E3c) passing through the respective areas gradually separated from the end portions 63a and 66a of the gaps 63 and 66 is subjected to being gradually slowed due to the separation. In other words, in the longitudinal direction B of the suction port 52, the speed of air (E8a) passing through the area of the end portion 52a on the side of the suction port 52 close to the exhaust port 53 becomes the fastest, and the speed of air (E8b, E8c, and E8d) passing through the respective areas gradually separated from the end portion 52a of the suction port 52 becomes gradually slowed (refer to
The air (E8) suctioned from the suction port 52 of the suction duct 51B as described above passes through the plural ventilation portions 71 of the permeable member 70 of the uppermost stream flow control member 61 to be suctioned with the traveling direction thereof aligned in the direction substantially orthogonal to the longitudinal direction B of the suction port 52, and the air suction velocity in the longitudinal direction B of the suction port 52 is controlled not to be considerably different. In addition, the wind speed of the air (E8) suctioned from the suction port 52 is controlled not to be considerably different in the longitudinal direction B of the opening shape (oblong shape) of the suction port 52 and is controlled not to be considerably different in the lateral direction C (refer to
The flow of the air (E8) that is suctioned from the suction port 52 into the flow path space 54a of the second bent flow path 54E is in a state of being controlled by the middle flow control member 65, and thus stays in a temporarily circulating state in the flow path space 54a of the second bent flow path 54E. In this manner, the air (E8) that is suctioned with the speed difference in the longitudinal direction B (and the lateral direction C) of the suction port 52 is mixed due to the temporary circulating stay and, as a result, the speed difference is alleviated and is cancelled to some extent.
The suction force of the air (E8) in the suction port 52 of the suction duct 51B is exerted also in the shield case 16a of the charge adjusting corona discharger 16 and the opening 16b thereof via the connection duct 56. In this manner, the air that is present in the shield case 16a of the charge adjusting corona discharger 16 and the air that is present in the vicinity of the opening 16b are suctioned from the suction port 52 of the suction duct 51.
In this case, the suction of the air in the suction port 52 of the suction duct 51B is allowed such that the suction of the air with little unevenness in the longitudinal direction B of the suction port 52 since the air suction velocity in the longitudinal direction B of the suction port 52 is controlled not to be considerably different, and thus the air (E5) that is present in the shield case 16a of the charge adjusting corona discharger 16 and the like is also suctioned in the suction duct 51 at the substantially same speed in the longitudinal direction B of the shield case 16a.
According to the suction duct 51B, during the operation of the charge adjusting corona discharger 16, the ozone and the corona products that are generated in and in the vicinity of the shield case 16a are suctioned substantially uniformly along with the air (E8) in the longitudinal direction B of the shield case 16a. Accordingly, in the imaging units 10 (Y, M, C, and K) in which the suction device 5(B) is installed, the generation of defects of the image quality such as concentration unevenness due to, for example, the suction of the air by the suction device performed extremely leaned in the axial direction of the photoconductive drum 11, which causes the ozone and the corona products that are generated in the charge adjusting corona discharger 16 adhere and accumulate in a state of being leaned in the axial direction of the image holding surface of the photoconductive drum 11 corresponding to the side where the suction of the air by the suction device is relatively weak, may be controlled.
As illustrated in
As illustrated in
One end portion of the suction flow path 254B is open with the suction port 252 disposed, and the other end portion thereof is connected to a part of a flow path space 254ab of the bent flow path 254A. The suction flow path 254B is a horizontally long square tube-shaped flow path in terms of the overall appearance of the flow path, which is formed to extend in the longitudinal direction B2 (direction substantially parallel to a coordinate axis Z) of the charge adjusting corona discharger 216 and is also formed to extend in a direction (direction substantially parallel to a coordinate axis X) away from the opening 216d of the charge adjusting corona discharger 216. A flow path space 254aa of the suction flow path 254B is also formed to have a horizontally long square tube shape substantially similarly to the overall appearance of the flow path. In addition, the bent flow path 254A is formed to extend in one direction of the longitudinal direction B2 of the charge adjusting corona discharger 216 after being connected to the other end portion of the suction flow path 254B, and is a square tube-shaped flow path in terms of the overall appearance of the flow path with one end portion thereof closed and the terminal end portion open as the exhaust port 253. The exhaust port 253 is present in the terminal end portion of the bent flow path 254A, and thus can be referred to as an exhaust flow path. The flow path space 254ab of the bent flow path (exhaust flow path) 254A is also formed to have a square tube shape substantially similarly to the overall appearance of the flow path.
The opening shape of the suction port 252 is a rectangular shape in the suction duct 251 according to the third embodiment while the opening shape of the exhaust port 253 is a substantially square shape. Since the shapes are different from each other, a bent part (connection part between the ventilation flow path 254B and the bent flow path 254A in actuality) is present in the (flow path space 254a of the) flow path 254. As a result, in the suction duct 251, the cross-sectional shape of the flow path space 254aa in the suction flow path 254B in particular is a rectangular shape widening only in a substantially horizontal direction while the cross-sectional shape of the flow path space 254ab in the bent flow path 254A is changed into a substantially square shape (with the height not changed). In other words, the cross-sectional shape of the flow path space 254ab of the bent flow path 254A is a cross-sectional shape that is rapidly narrowed in a substantially horizontal direction (direction substantially parallel to the coordinate axis X or Z) with respect to the flow path space 254aa of the suction flow path 254B.
As illustrated in
The flow control member 261 is disposed in the flow path space 254aa of the ventilation flow path 254B that is a part on a more upstream side than a part where the flow path space is bent between the ventilation flow path 254B and the bent flow path 254A of the flow path 254. Adopted as the flow control member 261 is what is shaped such that blocks a desired position of the suction flow path 254B with an elongated ventilation portion 263 present to cross a part of the flow path space 254aa in the suction flow path 254B in a direction (crossing direction) parallel to the longitudinal direction B2 of the suction port 252.
The flow control member 261 of the third embodiment is configured by arranging a plate-shaped blocking member 264 in the flow path space 254aa of the flow path 254B in a state of crossing at a constant gap with respect to one side surface 254b of the cross-sectional shape of the flow path space 254aa without changing the appearance of the suction flow path 254B. In detail, as illustrated in
In the flow control member 261, a band-shaped and continuously present gap (penetrating portion) between the (one end portion 264a of the) blocking member 264 and one inner wall surface 254b (lower surface portion of the flow path space 254aa) of the flow path space 254a is the ventilation portion 263 with an elongated shape. In addition, as illustrated in
In the flow control member 261, the height Sh2 of the ventilation portion 263 (penetrating portion), the path length Sm2, and the installation initiation position (distance D2 recessed inside from the suction port 252) illustrated in
Hereinafter, the operation of the suction device 205 will be descried.
The suction device 205 suctions a desired wind amount of the air with the suction machine 250 being driven to rotate first in a driving setting period such as during an image forming operation. When the suction machine 250 starts, the operation for suctioning and discharging the air (E200) is initiated in the suction machine 250 as illustrated in
In this case, the air (E202) that is present in the flow path space 254ab of the bent flow path 254A of the suction duct 251 is suctioned out from the exhaust port 253 first due to the suctioning force of the suction machine 250. In this manner, the air (E202) that is present in the flow path space 254ab of the bent flow path 254A flows substantially in an air flowing direction R201 in the flow path space 254ab, and ultimately passes through the exhaust port 253 as the collected discharge air (E201) right in front of the exhaust port 253 and flows out toward the connection duct 255. When the air is suctioned out from the exhaust port 253 in this manner, the suctioning force of the suction machine 250 is exerted in the flow path space 254ab of the bent flow path 254A.
Next, the air (E203) that is present in the flow path space 254aa of the suction flow path 254B is moved to be suctioned in the flow path space 254ab of the bent flow path 254A due to the suctioning force of the suction machine 250 exerted in the flow path space 254ab of the bent flow path 254A. As illustrated in
In this case, the air (E203) that is present in the flow path space 254aa of the suction flow path 254B flows in an air flowing direction R202 in the flow path space 254aa. However, the progress of the air (E203) is blocked by the blocking member 264 in the flow control member 261, and thus is put into a state of being capable of passing little by little through the elongated ventilation portion 263 in the flow control member 261, is put into a state of being suppressed in entirety (state where the pressure is increased), passes through the gap (penetrating portion) of the ventilation portion 263, and flows into the flow path space 254ab of the bent flow path 254A.
In this manner, the air (3203) that is suctioned and flows from the suction flow path 254B to the bent flow path 254A is, in general, tends to flow as the air (E203a) in a state of being concentrated and sided in an end portion area on a side of the suction flow path 254B close to the exhaust port 253 (suction machine 250 in reality) as illustrated in
As a result, the air (E203) does not pass in a state of relatively largely sided in the vicinity of the end portion 263a on a side of the longitudinal direction B2 of the ventilation portion 263 of the flow control member 261 close to the exhaust port 253 and passes in a substantially identical state (state of being substantially uniform with no unevenness) over the substantially entire area of the ventilation portion 263 in the longitudinal direction B2. In addition, since the air (E203) at least passes the ventilation portion 263 in the flow control member 261, the suctioning force of the suction machine 250 can also be exerted with respect to the flow path space 254aa of the suction flow path 254B on the upstream side of the air flowing direction R202 from the flow control member 261.
Lastly, the air (3204) that is present out of the suction port 252 is suctioned into the flow path space 254aa of the suction flow path 254B through the suction port 252 due to the suctioning force of the suction machine 250 exerted in the flow path space 254aa of the suction flow path 254B. In this case, the air (E204) is the air that is present in and in the vicinity of the shield case 216a of the charge adjusting corona discharger 216 in reality. When the air (E204) is suctioned into the passing space 254aa of the ventilation flow path 254B from the suction port 252, the suctioning force of the suction machine 250 is exerted out of the suction port 252.
In this case, the air (E204) that is suctioned from the suction port 252 becomes the air (E203) that is present by being moved into the flow path space 254aa of the suction flow path 254B, and then passes the ventilation portion 263 in the flow control member 261 in a substantially identical state over the substantially entire area in the longitudinal direction as described above, and thus is suctioned in a uniform state from an area space substantially close to the opening shape of the suction port 252.
Strictly, in the longitudinal direction B2 of the suction port 252, the speed of the air (E203a) that passes through the end portion 263a area on a side of the ventilation portion 263 close to the exhaust port 253 is the highest as illustrated in the example of
As described above, the air (E204) that is suctioned from the suction port 252 of the suction duct 251 passes through the elongated ventilation portion 263 in the uppermost stream flow control member 261, is suctioned such that the traveling direction thereof flows aligned in a direction substantially orthogonal to the longitudinal direction B2 of the suction port 252, and is put into a state where a substantial change in the speed of suctioning of the air in the longitudinal direction B2 of the suction port 252 is suppressed so that the speed is substantially uniform. In addition, a substantial change in the wind speed of the air (E204) that is suctioned from the suction port 252 is in a state of being suppressed in the longitudinal direction B2 of the opening shape (rectangular shape) of the suction port 252, and a substantial change in a short direction C2 (
The suctioning force of the air (E204) in the suction port 252 of the suction duct 251 is also exerted in the shield case 216a of the charge adjusting corona discharger 216 and the opening 216b thereof as well. In this manner, the air that is present in the shield case 216a of the charge adjusting corona discharger 216 and the air that is present in the vicinity of the opening 216 are suctioned from the suction port 252 of the suction duct 251.
The suctioning of the air in the suction port 252 of the suction duct 251 in this case allows the suctioning of the air in a state of being uniform with little unevenness in the longitudinal direction B2 with a substantial change in the speed of suctioning of the air in the longitudinal direction B2 of the suction port 252 suppressed, and the air (E204) that is present in the shield case 216a of the charge adjusting corona discharger 216 and the like is also suctioned into the (suction port 252 of the) suction duct 251 at a speed that is substantially identical to that in the longitudinal direction B2 of the shield case 216a thereof.
In this manner, the ozone and the corona products that are generated in and in the vicinity of the shield case 216a during the operation of the charge adjusting corona discharger 216 are suctioned substantially uniformly along with the air (E204) by the suction port 252 of the suction duct 251 in the longitudinal direction B2 of the shield case 216a. Accordingly, with an imaging unit 10 (Y, M, C, and K) where the suction device 205 is installed, the following inconvenience that occurs in a case where the suctioning of the air by the suction device 205 for example is performed extremely sided in an axial direction of the photoconductive drum 211 can be reduced. In other words, in a case where the suctioning of the air of the suction device 205 is performed extremely sided, the ozone and the corona products generated in the charge adjusting corona discharger 216 are adhered and deposited in a sided state in a part of the image holding surface of the photoconductive drum 211 in the axial direction corresponding to the site where the suctioning of the air by the suction device 205 is relatively weak, which results in the occurrence of poor image quality such as uneven concentration. However, the inconvenience described above can be reduced.
<Test A Relating to Suction Duct>
Test A is a simulation of the wind speed of the air passing through the front part of the ventilation portion 263 of the flow control member 261 in each of test examples (test No. 1 to 20) after the conditions of the flow control member 261 in the suction duct 251 having the following basic configuration are set to the respective values illustrated in
The simulation of Test A is performed on an assumption that the suction duct 251 has the overall shape illustrated in
The suction duct 251 with the suction port 252 having a height of 22 mm and a width W2 of 350 mm with a rectangular opening shape and the discharge port 253 having a height of 22 mm and a width L2 of 18 mm with a substantially square opening shape is used (
According to the object flow control member 261, the distance D2 recessed inside from the suction port 252 is 11 mm, and the path length Sm2 and the height Sh2 of the gap constituting the ventilation portion 263 at a position shifted by a distance N2 of 4 mm to 6 mm from the one end portion 253a of the exhaust port 253 on the upstream side in the air flowing direction R202 of the ventilation flow path 254B are configured by using the respective values illustrated in
In addition, the simulation of Test A assumes a case where each suctioning is performed by the suction machine 250 such that the wind volume at a time of suctioning of the air suctioned out from the exhaust port 253 of the suction duct 251 are the two types of values (low wind volume and high wind volume) illustrated in
Apparent from the result illustrated in
Apparent from the result illustrated in
Accordingly, in the suction duct 251, it can be said from the result of Test A that the unevenness of the suctioning state (wind speed) can be suppressed in the longitudinal direction of the suction port 252 when the height Sh2 of the ventilation portion 263 of the flow control member 261 is a value less than 5 mm with respect to the height H2 (22 mm) of the flow path space 254aa of the suction flow path 254B, furthermore, a value of equal to or less than ⅕ (≅ 5/22).
<Test B Relating to Suction Duct>
Test B is a simulation of the wind speed in the longitudinal direction B2 of the suction port 252 of each of the suction ducts 251 after the three following types are used as the suction duct 251. One of the suction ducts 251 is a suction duct having the configuration used in No. 1 of Test A described above (the ventilation portion 263 of the flow control member 261 being present below the flow path space 254aa). The second suction duct 251 (Test No. 15) is formed from the same basic configuration as the basic configuration (excluding the position of the ventilation portion 263) of the suction duct used in No. 1 of the Test A described above, and the ventilation portion 263 of the flow control member 261 is present in the middle in the height direction of the flow path space 254aa as illustrated in
The result in this case is illustrated in
Apparent from the result illustrated in
Strictly, a slight unevenness in the speed (wind speed) of suctioning of the air in the longitudinal direction B2 of the suction port 252 occurs in a case (Test No. 16.
For reference, the same simulation of Test B is performed on an assumption of a general suction duct (comparative example) 510X used in a suction device of the related art as illustrated in
The suction duct 510X has the same shape and basic configuration as the suction duct 251 applied in Test A (B), and is different only in that the uppermost stream flow control member 261 is not disposed in the suction flow path 254B. Sign 520 illustrated in
Apparent from the result illustrated in
In contrast, as is apparent from the result illustrated in
The two flow control members 61 and 62 are disposed in the first exemplary embodiment and the three flow control members 61, 62, and 65 are disposed in the second exemplary embodiment as the flow control members of the suction duct 51. However four or more flow control members may be disposed. Preferably, the flow control members including the lowermost stream flow control member are disposed at a site where the cross-sectional shape of the flow path space 54a of the main body portion 54 of any one of the suction ducts 51 changes and a site where the air flow direction in the flow path space 54a is changed (immediately after the change or the like).
In the first and second exemplary embodiments, the lowermost stream flow control member 62 is configured by using the permeable member 70 which is formed to have the plural ventilation portions (holes) 71 formed to be dotted substantially uniformly across the entire opening area of the exhaust port 53. However, for example, the lowermost stream flow control member 62 may be configured by using the permeable member 70 which is represented by a porous member (where the plural ventilation portions 71 are through-gaps with irregular shapes) such as a non-woven fabric which is applied to a filter or the like.
In addition, the overall shape of the suction duct 51 is not limited to the shapes illustrated in the first and second exemplary embodiments. The suction duct 51 may, for example, be applied to other shapes, examples of which include the suction duct 510 (510A to 510X) illustrated in
The object structure to which the suction device 5 (5B) is applied is not limited to the charge adjusting corona discharger 16 illustrated in the first and second exemplary embodiments, but may be other structures (component parts, component equipment, and the like) that requires the suction of the air and have a (object) part that is long in one direction. Examples of the other object structure include a vicinity part among the parts of the developing devices 14 facing the photoconductive drums 11 that is at least one of an upstream side and a downstream side of the photoconductive drums 11 in the rotation direction, a site between the drum cleaning devices 17 of the photoconductive drums 11 and the charging devices 12, and a vicinity part among the parts of the belt cleaning device 26 facing the intermediate image transfer belt 21 that is at least one of an upstream side and a downstream side of the intermediate image transfer belt 21 in the rotation direction. In addition, in the image holding members that are represented by the photoconductive drums 11 and the intermediate image transfer belt 21, the part where the waste materials such as the ozone and the toner may adhere to cause a deterioration in the image quality are the object structure which requires the suction of the air.
In addition, in the image forming apparatus 1, the configuration such as the image forming method is not particularly limited insofar as the image forming apparatus 1 is equipped with the object structure where the suction device 5 (5B) needs to be applied. If necessary, the image forming apparatus may be an image forming apparatus that forms an image formed of a material other than the developer.
The foregoing description of the exemplary embodiments of the present invention has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations will be apparent to practitioners skilled in the art. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, thereby enabling others skilled in the art to understand the invention for various embodiments and with the various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2013-218201 | Oct 2013 | JP | national |
| 2014-061708 | Mar 2014 | JP | national |
