JP2018036578A - Developing device and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing device that can reduce scattering of developer, and an image forming apparatus.SOLUTION: A developing device 200 comprises: a storage container 202 that stores a developer; a rotating body 260 that rotates while holding the developer to supply the developer to an image holding body 102; a channel forming member 270 that forms an exhaust channel part 290 in a space between an inner wall 203 of the storage container 202 and rotating body 260 through which air inside the storage container 202 is exhausted; and opening/closing means 276 that is provided at a portion of an exhaust port 294 exhausting air through the exhaust channel part 290 formed by the channel forming member 270, and is opened/closed according to the pressure inside the storage container 202.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a developing device and an image forming apparatus.

  As an invention of a developing device for preventing leakage of toner from a developing container, for example, Patent Document 1 listed below discloses a developing container that contains a two-component developer containing a magnetic carrier and toner, and an outer periphery from the opening of the developing container. A toner carrier that is disposed so as to face the image carrier by exposing a part of the surface, and that supplies toner to the image carrier while rotating so that the surface facing the image carrier moves upward; A magnetic brush made of a two-component developer carried on the surface of the toner carrier is disposed so as to face the toner carrier and rotates so that the surface facing the toner carrier moves in a direction opposite to the toner carrier. A developer carrier that forms a toner layer on the toner carrier, a regulating member that regulates the amount of developer carried on the developer carrier, and an upper end portion of the developer container that faces the toner carrier Air flow An air outflow passage communicating with a duct disposed in an upper portion of the developing container from an opening, wherein the air outflow passage passes through a rotation shaft center of the toner carrier and the air outflow port. A developing device is disclosed that is inclined to the downstream side in the rotation direction of the toner carrier with respect to a straight line.

  Patent Document 2 listed below is a developing device that includes a developing container that contains a developer containing toner, and a stirring member that stirs and conveys the developer in the developing container. A contact member provided in a state where it can contact the agitating member in the developing container with respect to an air discharge portion that communicates the inside and the outside, and is supported by the contact member and flows out from the inside of the developing container to the outside A developing device comprising: a developer adhering member that collects developer in the air and that is vibrated through the contact member by the stirring / conveying operation of the stirring member. Yes.

JP 2013-097217 A JP 2014-139630 A

  When the internal pressure rises due to air mixed with the developer in the developing device, there is a problem that the developer is scattered outside the developing device.

  The present invention provides a developing device capable of suppressing the scattering of the developer to the outside of the developing device, as compared with the case where the opening / closing means of the discharge flow path portion of the flow path forming member is not opened / closed according to the pressure in the storage container. An object of the present invention is to provide an image forming apparatus.

  According to a first aspect of the present invention, there is provided a storage container in which the developer is stored, a rotating body that supplies the developer to the image holding body by rotating in a state of holding the developer, and an inner wall of the storage container. A flow path forming member that forms a discharge flow path section that discharges air in the storage container in a space between the rotating body and a discharge that discharges air from the discharge flow path section of the flow path forming member. An opening / closing means provided at an outlet portion and opened / closed in accordance with a pressure in the storage container.

  The present invention according to claim 2 is the developing device according to claim 1, wherein the opening / closing means of the flow path forming member is a movable portion that can be repeatedly moved.

  According to a third aspect of the present invention, the opening / closing means of the flow path forming member is closed in a state where the opening / closing means is in contact with the inner wall of the storage container. The developing device according to claim 1, wherein the developing device is configured to be opened to discharge air.

  According to a fourth aspect of the present invention, the flow path forming member forms an inflow flow path portion for allowing air to flow into the storage container in a space between the rotating body and the flow path forming member. 4. The developing device according to claim 1, wherein a folding portion that is folded back to the inflow channel portion side is provided on the discharge port side. 5.

  According to a fifth aspect of the present invention, the flow path forming member forms an inflow flow path portion for allowing air to flow into the storage container in a space between the rotating body and the flow path forming member. 5. The shielding part protruding to the inflow channel part side is provided on a side opposite to the discharge port at a position where the developer separated from the rotating body comes into contact. The developing device described in 1.

  The present invention according to claim 6 is the developing device according to any one of claims 1 to 5, wherein the flow path forming member is formed of a film-like member.

  The present invention according to claim 7 supplies the developer to the image holding body by rotating the image holding body for holding the image, a storage container storing the developer, and the developer holding state. A rotating body, a flow path forming member that forms a discharge flow path section for discharging air in the storage container in a space between the inner wall of the receiving container and the rotating body, and the discharge of the flow path forming member An image forming apparatus comprising: a developing device having an opening / closing means provided at a discharge port portion for discharging air from the flow path portion and opened / closed according to a pressure in the storage container.

  According to the first aspect of the present invention, the developer is scattered outside the developing device as compared with the case where the opening / closing means of the discharge channel portion of the channel forming member is not opened / closed according to the pressure in the storage container. Can be suppressed.

  According to the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, the discharge port can be easily opened and closed as compared with the case where there is no movable part that can be repeatedly moved as the opening and closing means. Will be able to.

  According to the third aspect of the present invention, in addition to the effect of the present invention according to the first or second aspect, it is possible to prevent the developer from scattering from the discharge flow path portion.

  According to the fourth aspect of the present invention, in addition to the effect of the present invention according to any one of the first to third aspects, the developer is scattered from the inflow channel portion as compared with the case where the folded portion is not provided. Can be suppressed.

  According to the fifth aspect of the present invention, in addition to the effect of the present invention according to any one of the first to fourth aspects, the developer enters the discharge flow path portion as compared with the case where no shielding portion is provided. This can prevent the developer from scattering.

  According to the sixth aspect of the present invention, in addition to the effect of the present invention according to any one of the first to fifth aspects, compared with a case where the flow path forming member is formed of a member other than a film, an inexpensive material and simpler It can be formed with a simple structure.

  According to the seventh aspect of the present invention, the developer is scattered outside the developing device as compared with the case where the opening / closing means of the discharge flow path portion of the flow path forming member is not opened / closed according to the pressure in the storage container. An image forming apparatus having a developing device that can be suppressed can be provided.

1 is a diagram illustrating an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a diagram illustrating a developing device included in the image forming apparatus illustrated in FIG. 1. FIG. 3 is a view showing a state in which a flow path forming member is mounted on the main body of the developing device shown in FIG. 2 from the direction of arrow d shown in FIG. It is a figure which shows the use condition of the image development apparatus in a normal case. It is a figure which shows the use condition of a developing device when the pressure in a developing device main body rises.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiment described below exemplifies a developing device and an image forming apparatus for embodying the technical idea of the present invention, and is not intended to specify the present invention. Other embodiments within the scope of the claims are equally applicable.

[Embodiment]
FIG. 1 shows an image forming apparatus 10 according to an embodiment of the present invention. As shown in FIG. 1, the image forming apparatus 10 includes an image forming apparatus main body 12, and an image forming unit 100 and a paper feeding device 300 are provided in the image forming apparatus main body 12. In addition, a conveyance path 400 for conveying a sheet used as a recording medium is formed in the image forming apparatus main body 12.

  The image forming apparatus main body 12 is formed with a paper discharge port 14 for discharging paper. The upper surface of the image forming apparatus main body 12 is used as the discharge unit 16. The paper is discharged from the image forming apparatus main body 12 to the discharge unit 16 through the paper discharge port 14. A support plate 18 is attached to the image forming apparatus main body 12.

  The support plate 18 is a member for supporting the paper discharged from the image forming apparatus main body 12 together with the discharge unit 16, and can move so as to rotate about the hinge 20 with respect to the image forming apparatus main body 12. It is attached so that it can.

  The image forming unit 100 forms, for example, a monochromatic image and employs an electrophotographic system. The image forming unit 100 also includes a photosensitive member 102 used as an image holding member that holds an image, a charging device 110 that charges the photosensitive member 102, and light on the surface of the photosensitive member 102 that is charged by the charging device 110. The latent image forming apparatus 120 for forming an electrostatic latent image on the surface of the photoconductor 102 and the latent image formed on the photoconductor 102 are developed using a developer containing toner, and the surface of the photoconductor 102 is irradiated. A developing device 200 for forming a toner image on the surface, a transfer device 130 for transferring the toner image formed on the surface of the photosensitive member 102 by the developing device 200 to a sheet, and after the toner image is transferred to the sheet by the transfer device 130. A cleaning device 140 that cleans the photoreceptor 102 and a fixing device 150 that fixes the toner image transferred onto the paper by the transfer device 130 onto the paper.

  The charging device 110 includes a charging member 112. The charging member 112 has a roll shape, for example, and is disposed so as to be in contact with the photosensitive member 102 or close to the photosensitive member 102, and direct current or direct current is superimposed from a power supply (not shown). The charged voltage is applied to charge the photosensitive member 102.

  The developing device 200 is a so-called two-component developing device that develops a latent image using a developer in which a toner and a carrier are mixed. For example, a non-magnetic toner that is negatively charged, a magnetic carrier that is positively charged A developer in which etc. are mixed is used. Further, the developing device 200 moves the developing device main body 202 used as a developer storage container in which the developer is stored, and the toner in the developer stored in the developing device main body 202 to the photosensitive member 102. And a toner moving mechanism 250 which is a mechanism for this. Details of the developing device 200 will be described later.

  The transfer device 130 includes a transfer member 132. The transfer member 132 has, for example, a roll shape, and is disposed so as to be in contact with, for example, the photosensitive member 102. A voltage for transfer is applied from a power supply (not shown).

  The cleaning device 140 has a cleaning member 142. The cleaning member 142 is made of, for example, a plate-like member, one end of which is pressed against the photoconductor 102, and the developer or the like is removed from the surface of the photoconductor 102 at the pressed end to remove the photoconductor 102. to clean up.

  The fixing device 150 includes a heating roll 152 having a heat source therein, and a pressure roll 154 that comes into contact with the heating roll 152, and the toner transferred to the paper at the contact portion between the heating roll 152 and the pressure roll 154. The toner image is fixed on the paper by heating and pressurization.

  The paper feeding device 300 supplies paper toward the image forming unit 100. In addition, the paper feeding device 300 includes a paper storage container 302 that stores paper in a stacked state, and a delivery roll 304 that sends out the paper from the paper storage container 302.

  The conveyance path 400 conveys a sheet from the sheet feeding device 300 toward the transfer device 130, conveys the sheet from the transfer device 130 toward the fixing device 150, and conveys the sheet so as to be discharged from the image forming apparatus main body 12. It is a conveyance path for doing. In the vicinity of the conveyance path 400, the above-described delivery roll 304, registration roll 410, the above-described transfer device 130, and the above-described photosensitive member 102, and the above-described photosensitive element, sequentially from the upstream side in the sheet conveyance direction along the conveyance path 400. A fixing device 150 and a discharge roll 420 are disposed.

  The registration roll 410 temporarily stops the movement of the leading end of the sheet conveyed toward the contact position NP where the photoconductor 102 and the transfer member 132 are in contact with each other, and the timing at which the toner image is formed on the photoconductor 102. The movement toward the contact position NP of the leading end of the sheet is resumed so as to match.

  The discharge roll 420 discharges the paper on which the toner image is fixed by the fixing device 150 to the outside of the image forming apparatus main body 12.

  A in FIG. 1 indicates a supply region where the developer is supplied to the photosensitive member 102 from a developing sleeve 260 (see FIG. 2) described later.

  FIG. 2 shows a developing device 200. The developing device 200 includes the developing device main body 202 and the toner moving mechanism 250 as described above. As shown in FIG. 2, the toner moving mechanism 250 includes a magnet member 252 having a plurality of magnetic poles, and a developing sleeve 260. Details of the magnet member 252 and the developing sleeve 260 will be described later.

  The developing device main body 202 includes a lower main body portion 204 positioned below and a lid member 206 attached to the lower main body portion 204 so as to cover an opening formed on the upper side of the lower main body portion 204. For example, a lid member 206 of the developing device main body 202 is provided with a replenishment opening (not shown) so as to communicate the outside of the developing device main body 202 and the inside of the developing device main body 202. The toner is replenished into the developing device main body 202 from a toner container (not shown) through the opening.

  Further, the developing device 200 includes a layer thickness regulating member 240 that regulates the layer thickness of the developer adsorbed on the surface of the developing sleeve 260. The layer thickness regulating member 240 is attached to the developing device main body 202 so as to form a predetermined gap between the end portion on the developing sleeve 260 side and the developing sleeve 260.

  Further, the developing device 200 includes an agitating and conveying member 210 that agitates the developer stored in the developing device main body 202 and conveys the developer to the toner moving mechanism 250. The agitating and conveying member 210 has a shaft portion 212 and a blade portion 214 formed in a spiral shape on the outer peripheral surface of the shaft portion 212, and the shaft portion 212 and the blade portion 214 are integrally formed in the direction of arrow a shown in FIG. And the blades 214 press the developer so that the developer is stirred in the developing device main body 202 and the developer is conveyed. The agitating / conveying member 210 conveys the developer in the longitudinal direction of the agitating / conveying member 210 (the direction perpendicular to the paper surface in FIG. 2) and moves it in the direction of the toner moving mechanism 250 (in FIG. 2, from the right side to the left side). Transport the developer).

  Further, the developing device 200 includes a stirring and conveying member 220. The agitating and conveying member 220 includes a shaft portion 222 and a blade portion 224 formed in a spiral shape on the outer peripheral surface of the shaft portion 222, and the shaft portion 222 and the blade portion 224 are integrally formed in the direction of arrow b shown in FIG. And the blade 224 presses the developer so that the developer is stirred in the developing device main body 202 and the developer is transported. More specifically, the stirring and conveying member 220 conveys the developer in the longitudinal direction of the stirring and conveying member 220. By the agitating and conveying member 220 and the agitating and conveying member 210 described above, the developer is conveyed while being agitated in the developing device main body 202, so that the toner in the developer rubs against the carrier and the like, and the friction with the carrier and the like. The toner is charged.

  The developing sleeve 260 is used as a rotating body that supplies the developer to the photosensitive member 102 by rotating in a state where the developer is held. Further, the developing sleeve 260 rotates in a state where the developer is held, and thereby rotates, in particular, the toner in the developer to the photosensitive member 102 (see FIG. 1) in the supply region A (see FIG. 1). It is used as a body. The developing sleeve 260 is made of a nonmagnetic material and has, for example, a cylindrical shape. Further, the developing sleeve 260 is connected to a motor or the like (not shown) used as a driving source via a drive transmission mechanism (not shown) constituted by, for example, a gear train or the like. 2 is transmitted through the drive transmission mechanism, and rotates in the direction of the arrow c shown in FIG.

  The magnet member 252 has, for example, a cylindrical shape and includes a plurality of magnetic poles extending in the longitudinal direction of the magnet member 252. More specifically, the magnet member 252 has, for example, five magnetic poles, that is, five magnetic poles, that is, an attracting magnetic pole S1, a conveying magnetic pole N1, a developing magnetic pole S2, a conveying magnetic pole N2, and a separating magnetic pole S3. I have.

  The attracting magnetic pole S <b> 1 is used to attract the developer conveyed to the developing sleeve 260 side by the agitating and conveying member 210 to the surface of the developing sleeve 260. Here, the above-described layer thickness regulating member 240 is disposed so that the end portion on the developing sleeve 260 side is within the range of the magnetic force of the attracting magnetic pole S1. For this reason, the developer that cannot pass through the gap between the developing sleeve 260 and the layer thickness regulating member 240 out of the developer adsorbed on the developing sleeve 260 by the magnetic force of the attracting magnetic pole S 1 is caused by the layer thickness regulating member 240. The layer thickness of the developer peeled from the surface of the developing sleeve 260 and adsorbed on the developing sleeve 260 is regulated.

  The conveying magnetic pole N1 is disposed downstream of the attracting magnetic pole S1 in the rotation direction of the developing sleeve 260, and maintains the adsorption of the developer to the surface of the developing sleeve 260, thereby rotating the developing sleeve 260. Along with this, it is used to transport the developer. The developing magnetic pole S2 is disposed downstream of the conveying magnetic pole N1 in the rotation direction of the developing sleeve 260, and the toner moves from the surface of the developing sleeve 260 to the photosensitive member 102 (see FIG. 1). It is used to develop an electrostatic latent image that is disposed in the vicinity of the region and formed on the surface of the photosensitive member 102 using toner.

  The conveyance magnetic pole N2 is disposed downstream of the development magnetic pole S2 in the rotation direction of the developing sleeve 260, and maintains the adsorption of the developer to the surface of the developing sleeve 260 in the same manner as the conveyance magnetic pole N1 described above. Therefore, the developer is transported as the developing sleeve 260 rotates. The separation magnetic pole S <b> 3 is disposed downstream of the conveyance magnetic pole N <b> 2 in the rotation direction of the developing sleeve 260 and is used for separating the developer from the surface of the developing sleeve 260.

  In the developing device 200, when the rotation center of the developing sleeve 260 is the rotation center O, the angle θ1 between the separation magnetic pole S3 and the suction magnetic pole S1 around the rotation center O is 135 degrees (deg). It has become.

  The two-dot chain line in FIG. 2 indicates the surface of the developing sleeve 260 with a magnetic field formed by each of the attracting magnetic pole S1, the conveying magnetic pole N1, the developing magnetic pole S2, the conveying magnetic pole N2, and the separating magnetic pole S3 provided in the magnet member 252. The position in which the component in the direction perpendicular to is 20 mT is shown. For this reason, the portion with the longest distance from the center of the magnet member 252 to the two-dot chain line drawn so as to surround each magnetic pole indicates the position where the magnetic pole is maximum. P <b> 1 in FIG. 2 indicates a position where the developer is separated from the surface of the developing sleeve 260.

  Further, the developing device 200 includes a flow path forming member 270 that forms an inflow flow path section 280 described later and a discharge flow path section 290 described later.

  As shown in FIGS. 2 to 5, the flow path forming member 270 is formed of a member having a certain area that can be repeatedly moved, such as a film-like member. A plurality of, for example, five support members 272a, 272b, 272c, 272d, and 272e are attached to the inner wall 203 so that a space is formed between the path forming member 270 and the inner wall 203 of the developing device main body 202. ing. A space between the flow path forming member 270 and the inner wall 203 is used as a discharge flow path section 290 (see FIGS. 2 and 5). An arrow f in FIG. 5 schematically shows the flow of air discharged from the developing device main body 202 to the outside of the developing device main body 202 so as to pass through the discharge flow path section 290. The support members 272a, 272b, 272c, 272d, and 272e may be collectively referred to as the support member 272.

  2 to 5, the flow path forming member 270 attached to the support member 272 is disposed between the inner wall 203 and the developing sleeve 260, and the developing sleeve 260 and the flow path are arranged. A space between the forming member 270 and the inflow channel portion 280 is used.

  In the inflow passage portion 280, an inflow port 282 through which air flows in, for example, a supply region A (FIG. 1) in which toner in the developer is supplied from the developing sleeve 260 to the photosensitive member 102 (see FIG. 1). Is also arranged on the downstream side in the rotation direction of the developing sleeve 260 as indicated by an arrow c. Further, the inflow passage portion 280 has an air outlet 284 disposed in the developing device main body 202. Then, air flows in from the inflow port 282 so that the air flows into the inflow channel portion 280 as the developing sleeve 260 rotates in the direction of the arrow c, and the inflowed air passes through the outlet 284. Then, it flows into the developing device main body 202. 4 and FIG. 5 schematically shows the flow of air flowing from the outside of the developing device main body 202 into the developing device main body 202 so as to pass through the inflow flow passage portion 280.

  Further, the discharge flow path section 290 is provided in the developing device main body 202 so that air in the developing device main body 202 flows in from an inlet 292 disposed in the developing device main body 202 and is discharged from the discharge port 294. The air is discharged out of the developing device main body 202. The inlet 292 is disposed in the vicinity of the outlet 284 of the inflow channel portion 280. More specifically, the inlet 292 is adjacent to the outlet 284 so as to sandwich one end of the flow path forming member 270 (see FIG. 5).

  At this time, the discharge port 294 of the discharge flow path portion 290 of the embodiment is configured to be opened and closed by repeatedly moving the movable portion 276 as the opening and closing means of the flow path forming member 270, as will be described later. (See FIGS. 4 and 5).

  The flow path forming member 270 of the embodiment is provided between the inner wall 203 of the developing device main body 202 and the developing sleeve 260 so as to form the inflow flow path section 280 and the discharge flow path section 290 as described above. Are attached to the inner wall 203 of the developing device main body 202 via respective support members 272.

  At this time, as shown in FIG. 3, each support member 272 is provided on the inlet 292 side of the discharge channel portion 290, and the channel forming member 270 is attached only on the inlet 292 side. ing. On the other hand, the discharge port 294 side of the discharge flow channel portion 290 of the flow channel forming member 270 is a free end, and the discharge port 294 side can be repeatedly moved so that the discharge flow channel portion 290 is opened and closed. ing.

  In addition, the discharge port 294 side of the flow path forming member 270 of the flow path forming member 270 is normally provided so that the discharge port 294 side is closed (see FIGS. 2 and 4). When the pressure in the developing device main body 202 becomes high, the discharge port 294 is opened by the internal pressure in the developing device main body 202, and air is discharged from the discharge flow path portion 290 (see FIG. 5). ).

  As shown in FIGS. 3 to 5, the flow path forming member 270 includes a substantially rectangular main body portion 274 having a certain area, and an attachment portion attached to the support member 272 on one side of the main body portion 274. 275 is provided, and on the other side, a movable portion 276 as an opening / closing means is provided, which is formed of a film-like member. The flow path forming member 270 is curved along the inner wall 203 of the developing device main body 202. The movable portion 276 is a portion that opens and closes the discharge port 294 of the discharge flow path portion 290.

  The flow path forming member 270 is formed of a film-like member, and the thickness thereof can be formed in the range of 10 μm to 2 mm. If it is thinner than 10 μm, it is easy to break, and if it is thicker than 2 mm, it is difficult to move repeatedly.

  In addition, a folded portion 277 is formed from the end of the tip of the movable portion 276 side so as to be folded inward, that is, toward the inflow channel portion 280, and extends in the air inflow direction. . The folded portion 277 serves to prevent the developer that has flowed back through the inflow channel portion 280 from the inside of the developing device main body 202 from being scattered outside the developing device 200. In addition, although the folding | returning part 277 is formed even in part, it can acquire the effect of scattering prevention, but it can prevent scattering more by being provided so that the developing sleeve 260 may be contact | connected. At this time, the folded-back portion 277 is provided along the flow-in channel portion 280 from the front end side of the flow channel forming member 270 and is provided along the rotation direction of the developing sleeve 260. Rotation is not hindered.

  In addition, the movable portion 276 of the flow path forming member 270 is a free end that can be moved repeatedly, but in a normal state, the movable portion 276 comes into contact with the inner wall 203 of the developing device main body 202 and is discharged. The discharge port 294 of the flow passage section 290 is closed (see FIG. 4).

  In addition, a shielding portion 278 that is bent toward the inflow channel portion 280 is formed from the end of the tip on the attachment portion 275 side. The shielding portion 278 is configured to prevent the developer separated from the developing sleeve 260 from jumping and scattering, and to prevent the developer from dropping in the vicinity of the inlet 292 of the discharge channel portion 290. By providing the shielding portion 278 in this way, it is possible to suppress the developer from entering the discharge channel portion 290.

  The flow path forming member 270 is formed of a film-like member and has a spring property and is formed of a material that can be repeatedly moved. Examples of the material of the flow path forming member 270 include linear low density polyethylene, metallocene, ethylene / vinyl acetate copolymer resin, non-axially stretched polypropylene, biaxially stretched polypropylene, nylon film, polyethylene terephthalate, and polyethylene naphthalate. , Ionomer, polyvinyl alcohol, ethylene / vinyl alcohol copolymer resin, polyvinyl chloride, acrylonitrile resin, polycarbonate, fluorine film, polyurethane, cellulosic film, polyimide, polybutylene terephthalate, polyphenylene sulfide, nylon 6, nylon 66, nylon 11.12, polyacetal, polystyrene, polybutylene, phenol resin, silicone, urea resin, unsaturated polyester resin, terephthalate, methacryl Fat, polyacetal, polychlorinated polyethylene, high density polyethylene, medium density polyethylene, low density polyethylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl acetate, polytetrafluoroethylene, acrylonitrile butadiene styrene resin, acrylonitrile styrene resin, Acrylic resin, polymethyl methacrylate resin, polypropylene, polyvinylidene chloride, polyphenylene sulfide, polysulfone, polyethersulfone, amorphous polyarylate, liquid crystal polymer, polyetheretherketone, thermoplastic polyimide, polyamideimide, epoxy resin, melamine Resins, diallyl phthalate resins, synthetic resins such as ethylene vinyl acetate, polyamide, polycarbonate, and iron, silver, lead, zinc, copper, aluminum, etc. It may be made of a metal material and its alloys.

  Next, with reference to FIGS. 4 and 5, a usage mode of the developing device 200 provided with the flow path forming member 270 of the embodiment will be described. The developing device 200 is used in one process in which the image forming apparatus 10 is used as described above.

  When the flow path forming member 270 is normal, that is, when the pressure in the developing device main body 202 is not increased or is substantially equal to the atmospheric pressure, the flow path forming member 270 is movable as shown in FIG. The portion 276 side is arranged in contact with the inner wall 203 side of the developing device main body 202, and the discharge port 294 of the discharge flow path portion 290 is closed, and the developing device 200 is used in this state. By adopting such a configuration, air is not discharged from the inside of the developing device main body 202, so that the developer in the developing device main body 202 is prevented from being scattered outside the developing device 200.

  On the other hand, as described above, when the developing sleeve 260 passes through the inflow channel portion 280 and flows into the developing device main body 202 as the developing sleeve 260 rotates in the direction of arrow c, the atmospheric pressure in the developing device main body 202 increases. There is. The increase in the atmospheric pressure becomes more remarkable as the rotation of the developing sleeve 260 is increased, for example, as the image forming apparatus 10 increases the speed at which an image is formed. Note that a folded portion 277 is formed on the inlet 282 side of the inflow channel portion 280 of the flow channel forming member 270, but since it is formed along the inflow channel portion 280, the flow of air As a result, the folded portion 277 floats and a gap is formed, so that air is introduced. In particular, the larger the rotation of the developing sleeve 260, the larger the gap between the folded portions 277 due to the air flow, and the air flows in.

  At this time, the flow path forming member 270 of the embodiment is provided with the movable portion 276, so that as shown in FIG. When the movable portion 276 of the portion 290 moves and the discharge port 294 opens, the air in the developing device main body 202 is discharged through the discharge flow passage portion 290, and the pressure in the developing device main body 202 is reduced. The rise can be suppressed.

  Further, the movable portion 276 of the flow path forming member 270 is brought into the original state by the spring force of the movable portion 276 of the flow path forming member 270, that is, the movable portion 276 is moved to the developing device by the pressure in the developing device body 202 being lowered. Returning to the position in contact with the inner wall 203 of the main body 202, the discharge port 294 is automatically closed. At this time, since the folded portion 277 is formed on the movable portion 276 of the flow path forming member 270, the folded portion 277 pushes up the movable portion 276, so that the discharge port 294 can be reliably closed.

  In the embodiment, the flow path forming member 270 has been described as being entirely formed of a film-like member. However, the present invention is not limited thereto, and only the movable portion 276 has a spring property and can be repeatedly moved. It is also possible to form with the members. Even with such a configuration, the discharge port 294 of the discharge flow path section 290 can be opened and closed. At this time, the folded portion 277 is preferably formed of the same material as the movable portion 276.

  Further, in the flow path forming member 270 of the embodiment, the case where the folded part 277 and the shielding part 278 are provided has been described. However, the present invention is not limited thereto, and the folded part 277 and the shielding part 278 are not formed on the flow path forming member. However, by opening and closing the discharge port 294 of the discharge flow path section 290 by the movable section 276 of the flow path forming member, it is possible to suppress the scattering of the developer in the development apparatus main body 202 and to develop the main body of the development apparatus. When the pressure in 202 rises, air can be discharged and the effects of the present invention can be achieved. In addition, you may make it provide either one of a folding | turning part and a shielding part in a flow-path formation member.

  Further, in the embodiment described above, an example in which a single color image is formed as the image forming unit 100 is shown as an example. However, the present invention is also applied to an apparatus that forms a multicolor image as the image forming unit 100. Can be applied.

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 12 Image forming apparatus main body 102 Photosensitive body (Image holding body)
200 Developing Device 202 Developing Device Body (Storage Container)
203 Inner wall 206 Lid member 260 Developing sleeve (rotating body)
270 Flow path forming members 272a, 272b, 272c, 272d, 272e Support member 274 Main body 275 Mounting portion 276 Movable portion (opening / closing means)
277 Folding portion 278 Shielding portion 280 Inflow passage portion 282 Inlet 284 Outlet 290 Discharge passage portion 292 Inlet 294 Discharge port

Claims (7)

A storage container containing a developer;
A rotating body that supplies developer to the image holding body by rotating in a state of holding the developer;
A flow path forming member that forms a discharge flow path section for discharging the air in the storage container in a space between the inner wall of the storage container and the rotating body;
An opening / closing means provided at a discharge port portion for discharging air from the discharge flow path portion of the flow path forming member, and opened and closed according to the pressure in the storage container;
A developing device.   The developing device according to claim 1, wherein the opening / closing means of the flow path forming member is a movable portion that can be repeatedly moved.   The opening / closing means of the flow path forming member is configured such that the discharge port is closed while being in contact with the inner wall of the storage container, and the discharge port is opened by the pressure in the storage container to discharge air. The developing device according to claim 1, wherein: The flow path forming member forms an inflow flow path section for allowing air to flow into the storage container in a space between the rotating body,
4. The developing device according to claim 1, wherein a folding portion that is folded back to the inflow channel portion side is provided on the discharge port side of the channel forming member. 5. The flow path forming member forms an inflow flow path section for allowing air to flow into the storage container in a space between the rotating body,
A shielding part protruding to the inflow channel part side is provided at a position opposite to the discharge port of the channel forming member at a position where the developer separated from the rotating body comes into contact. Item 5. The developing device according to any one of Items 1 to 4.   The developing device according to claim 1, wherein the flow path forming member is formed of a film-like member. An image carrier for holding an image;
A storage container containing a developer;
A rotating body that supplies the developer to the image holding body by rotating in a state of holding the developer;
A flow path forming member that forms a discharge flow path section for discharging the air in the storage container in a space between the inner wall of the storage container and the rotating body;
A developing device having an opening / closing means provided at a discharge port portion for discharging air from the discharge flow path portion of the flow path forming member, and opened and closed according to the pressure in the storage container;
An image forming apparatus.

Images