Developer container and image forming apparatus

Abstract

The developer receiver and image forming apparatus are capable of smoothly discharging developer. The developer receiver includes: a housing (Ct) having a developer outlet for discharging developer; a conveying screw that, while rotating, axially conveys developer toward the developer outlet; an induction wall (51) that induces developer along the axial direction of the conveying screw; and a pushing member that rotates with the conveying screw to push developer into the developer outlet. A cutout is formed in the induction wall (51) corresponding to the pushing member to guide the developer to the developer outlet. Without scraping against the induction wall, the developer can be reliably pushed into the developer outlet by the pushing member, enabling smooth developer discharge.

Description

Technical Field

[0001] This invention relates to a developer container and an image forming apparatus. Background Technology

[0002] Conventionally, image forming devices (such as printers), copiers, fax machines, and multifunction printers are equipped with image forming units. In these units, the surface of a photosensitive drum, uniformly charged by a charged roller, is exposed to an LED head to form an electrostatic latent image. This latent image is then developed using toner supplied from a toner receiver (which also serves as a developer receiver) to form a toner image. This toner image is then transferred to paper by a transfer roller. Furthermore, in the fuser unit of the printer, the toner image is fixed to the paper to form an image, which is then printed.

[0003] Additionally, a toner receiver is provided that uses a driving force transmitted from a predetermined drive source provided in the printer to rotate a screw to deliver toner.

[0004] In this toner receiver, an induction wall is formed on the bottom surface of the toner receiver extending along the screw. When the screw rotates, the toner is induced through the induction wall toward the toner outlet formed on the bottom surface of the toner receiver (see, for example, Patent Document 1).

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-71405

[0006] However, in the existing toner receiver, the membrane installed at the front end of the screw scrapes against the induction wall near the toner outlet to discharge the toner. As a result, some toner cannot pass over the induction wall and cannot be discharged smoothly. Summary of the Invention

[0007] The purpose of this invention is to solve the problems of existing toner receivers and to provide a developer receiver and image forming apparatus that can smoothly discharge developer.

[0008] Therefore, the developer receiver of the present invention comprises: a housing for receiving developer and having a developer outlet for discharging developer; a conveying screw rotatably disposed within the housing and conveying developer axially toward the developer outlet as it rotates; an induction wall disposed along the conveying screw and inducing developer axially along the conveying screw; and a pushing member mounted on the conveying screw and rotating together with the conveying screw to push developer into the developer outlet.

[0009] Furthermore, a cutout is formed in the portion of the induction wall corresponding to the push-in component to guide the developer to the developer outlet.

[0010] According to the present invention, a developer receiver comprises: a housing for receiving developer and having a developer outlet for discharging developer; a conveying screw rotatably disposed within the housing and conveying developer axially toward the developer outlet as it rotates; an induction wall disposed along the conveying screw and inducing developer axially along the conveying screw; and a pushing member mounted on the conveying screw and rotating together with the conveying screw to push developer into the developer outlet.

[0011] Furthermore, a cutout is formed in the portion of the induction wall corresponding to the push-in component to guide the developer to the developer outlet.

[0012] In this case, a cut is formed by cutting off the portion of the induction wall that corresponds to the pusher component along the conveying screw. Therefore, the developer can be reliably pushed into the developer outlet by the pusher component without scraping against the induction wall.

[0013] Therefore, the developer can be discharged smoothly. Attached Figure Description

[0014] Figure 1 This is a cross-sectional view of the toner receiver in an embodiment of the present invention.

[0015] Figure 2 This is a conceptual diagram of a printer according to an embodiment of the present invention.

[0016] Figure 3 This is a longitudinal sectional view of the toner receiver in an embodiment of the present invention.

[0017] Figure 4 yes Figure 3 XX sectional view.

[0018] Figure 5 This is a perspective view of the screw in an embodiment of the present invention.

[0019] Figure 6 yes Figure 3 YY sectional view.

[0020] Label Explanation

[0021] 17i: Toner receiver; 38: Screw; 51: Induction wall; Ct: Housing; Fma: Membrane; h1: Toner outlet; Sb: Inclined surface; T: Toner. Detailed Implementation

[0022] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this case, a printer, which is an image forming apparatus, will be described.

[0023] Figure 2 This is a conceptual diagram of a printer according to an embodiment of the present invention.

[0024] In the diagram, 10 is the printer, Cs is the outer casing of the printer 10, and Bd is the main body of the printer 10, i.e., the device body.

[0025] A paper box 11 serving as a media storage unit is provided at the lower part of the main body Bd of the device. Paper P, which serves as the medium, is stored in the paper box 11 while being stacked in the stacking part sk1. Furthermore, a jump roller 13 serving as a delivery member is provided at the front end of the paper box 11. By rotating the jump roller 13, the paper P in the paper box 11 is separated one by one and delivered to the paper transport path Rt1, which serves as the media transport path. The paper is then transported on the paper transport path Rt1 by the feed roller pair m1, which serves as the first transport member, and delivered to the image forming unit Q1, which is located further downstream than the feed roller pair m1.

[0026] The image forming unit Q1 consists of multiple image forming units 16i (i = 1, 2, ..., 4) of four colors, such as black, yellow, magenta, and cyan; toner receivers 17i (i = 1, 2, ..., 4) that store toners of each color as developers and supply them to each image forming unit 16i; LED heads 23i (i = 1, 2, ..., 4) that serve as exposure devices; and a transfer unit u1. After the toner is supplied in the direction of arrow A, the toner receiver 17i discharges in the direction of arrow B, supplying it to the image forming unit 16i.

[0027] Furthermore, each image forming unit 16i is equipped with a photosensitive drum 21 as an image carrier, a charged roller 22 as a charging device, a developing roller 24 as a developer carrier, and a cleaning roller 25 as a cleaning component. The surface of the photosensitive drum 21, which is uniformly charged by the charged roller 22, is exposed by the LED head 23 to form an electrostatic latent image as a latent image. This electrostatic latent image is developed by the developing roller 24, and toner supplied from the toner receiver 17i adheres to it, forming toner images of each color as developer images on the surface of each photosensitive drum 21.

[0028] Furthermore, the transfer unit u1 includes a drive roller r1 as the first roller, a driven roller r2 as the second roller, a transfer belt 26 as a belt component that is freely stretched between the drive roller r1 and the driven roller r2, and transfer rollers 28i (i = 1, 2, ..., 4) as transfer components that are arranged in a rotatable manner opposite to each photosensitive drum 21 across the transfer belt 26.

[0029] Paper P is fed to the image forming unit Q1. During the transfer section between the photosensitive drum 21 of each image forming unit 16i and the transfer roller 28i, the toner images of each color are sequentially superimposed and transferred onto the paper P by the transfer roller 28i to form a colored toner image. After the toner images of each color are transferred onto the paper P, the toner remaining on the photosensitive drum 21 is scraped off and removed by the cleaning roller 25.

[0030] In addition, for ease of explanation, only one of each of the image forming unit 16i, toner receiver 17i, LED head 23i, and transfer roller 28i is shown in the figure.

[0031] A fuser 31, serving as a fixing device, is disposed downstream of the image forming unit Q1 in the paper transport path Rt1. The fuser 31 has a heating roller 32 serving as a first fixing component and a pressure roller 33 serving as a second fixing component. A heater (not shown) serving as a heating source is disposed inside the heating roller 32.

[0032] In the fuser 31, during the period when the paper P is conveyed in the fixing section between the heating roller 32 and the pressure roller 33, the toner on the paper P is heated and melted by the heating roller 32, and then pressed and fixed onto the paper P by the pressure roller 33.

[0033] In this way, the paper P, which has been fixed with the toner image, is conveyed by the conveyor roller pair m2, which is the second conveyor component, and discharged by the discharge roller pair m3, which is the third conveyor component, to the outside of the main body Bd of the device, and piled up in the stacking section sk2.

[0034] Next, the toner holder 17i will be described.

[0035] Figure 1 This is a cross-sectional view of the toner receiver in an embodiment of the present invention. Figure 3 This is a longitudinal sectional view of the toner receiver in an embodiment of the present invention. Figure 4 yes Figure 3 XX sectional view, Figure 5 This is a perspective view of the screw in an embodiment of the present invention. Figure 6 yes Figure 3 The YY sectional view. Additionally... Figure 1 yes Figure 3 ZZ sectional view.

[0036] In the attached drawings, 17i is a toner receiver, and Ct is the outer shell (case) of the toner receiver 17i. The case has a front plate Pf on the downstream side (front side) of the paper P in the conveying direction of the paper P, a rear plate Pr on the upstream side (rear side) of the paper P in the conveying direction of the paper P, a top plate Pt on the upper side, and a bottom plate Pb on the lower side. Viewed from the upstream side of the paper P in the conveying direction of the paper P, there is a side plate Ps1 on the left side and a side plate Ps2 on the right side. The toner is stored inside the case Ct.

[0037] The toner receiver 17i is located in the image forming unit 16i ( Figure 2 The upper part of the device is mounted on the printer 10 at an angle of, for example, 10° relative to the horizontal direction, with the end higher than the rear end. Therefore, the projected area relative to the horizontal plane can be reduced, thus enabling the printer 10 to be miniaturized.

[0038] At the end of the housing Ct, i.e., at the upper end of the bottom plate Pb, a toner outlet h1 is formed, which serves as a developer outlet for discharging toner T to the toner receiver 17i. Furthermore, an opening / closing member 41, used to open and close this toner outlet h1, is configured to move freely relative to the housing Ct in the direction of arrow A, and is positioned in a closed position and an open position as it moves. In the closed position, the toner outlet h1 is closed; in the open position, the toner outlet h1 is open. Additionally, a sealing member 43, formed of an elastomer, is disposed at the toner outlet h1 in a manner that surrounds the outer periphery of the toner outlet h1. When the opening / closing member 41 is in the closed position, the sealing member 43 seals the gap between the bottom plate Pb of the housing Ct and the opening / closing member 41.

[0039] In addition, a handle 35 is formed above the outer surface of the rear plate Pr of the housing Ct, on which the operator places his hand when removing the toner receiver 17i from the image forming unit 16i and pulling it out of the printer 10.

[0040] Furthermore, within the housing Ct, a toner delivery section Ar1, serving as a developer delivery section, is formed on the side plate Ps1, and a toner storage section Ar2, serving as a developer storage section, is formed on the side plate Ps2. These sections are adjacent to the induction wall 51, which will be described later. A screw 38, serving as a delivery spiral, is provided in the toner delivery section Ar1, and a stirring device 39, serving as a developer storage and delivery component, is provided in the toner storage section Ar2. These components extend along the length of the housing Ct, are parallel to each other, and are freely rotatable. Additionally, the screw 38 and the stirring device 39 rotate under the influence of a drive source (not shown) provided in the printer 10.

[0041] The screw 38 has a shaft component Sha, blades Wg formed around the shaft component Sha at a predetermined interval and made of helical elements, a connecting portion Cna formed at the end of the front plate Pf side of the shaft component Sha and having a D-shaped cross section, and a supported portion Spa formed at the end of the rear plate Pr side of the shaft component Sha and having a circular plate shape. As it rotates in the direction of arrow C, it conveys toner T axially (in the direction of arrow A) from the rear plate Pr toward the front plate Pf side, i.e. toward the toner outlet h1.

[0042] Furthermore, a membrane Fma, made of an elastomer, is installed at the flat part (D-cut part) of the connecting part Cna at the end of the screw 38 as a pushing member. The membrane Fma rotates with the rotation of the screw 38, pushing the toner T around the toner outlet h1 into the toner outlet h1 for delivery.

[0043] The screw 38 has a drive force transmission part 46 embedded in the connecting part Cna at its end, and a supported part Spa and a support part 47 formed on the inner wall of the rear plate Pr are engaged at its rear end, thereby being supported to rotate freely.

[0044] The drive force transmission section 46 is supported by a bearing hole section H1 formed by two through holes in the front plate Pf, allowing it to rotate freely. It has a drive force input section 46a formed by a stepped cylindrical shape and a drive force output section 46b with a D-shaped cross-section. Furthermore, the engagement hole h3 formed in the drive force input section 46a engages with a shaft (not shown) of the drive force transmission system that transmits drive force from the drive source, and the drive force output section 46b engages with the engagement hole h4 formed in the connecting section Cna (D-cut engagement).

[0045] Thus, the driving force transmitted from the drive source is transmitted to the screw 38 via the driving force transmission unit 46.

[0046] In addition, an annular sealing member 48 is provided between the end of the screw 38 and the inner surface of the front plate Pf, and the screw 38 and the front plate Pf are sealed.

[0047] The stirring device 39 has a shaft component Shb, a connecting portion Cnb formed at the end of the front plate Pf side of the shaft component Shb and having a D-shaped cross section, and a supported portion Spb formed at the end of the rear plate Pr side of the shaft component Shb and having a cylindrical shape.

[0048] Furthermore, a membrane Fmb, made of an elastomer and serving as an ejector, is installed on the shaft component Shb. The membrane Fmb rotates along with the rotation of the stirring device 39 in the direction of arrow D, stirring the toner T in the toner storage section Ar2, and conveying the toner T on the ejector plate Pb towards the induction wall 51 in the direction of arrow E.

[0049] The stirring device 39 has a driving force transmission part (not shown) for stirring, identical to the driving force transmission part 46, embedded in the connecting part Cnb at its front end, and at its rear end, the supported part Spb and the support part 49 formed on the inner wall of the rear plate Pr are engaged, thereby enabling it to rotate freely. The driving force from the driving source is transmitted to the stirring device 39 via the driving force transmission part for stirring.

[0050] However, the screw 38 delivers the toner T axially, i.e., in the direction of arrow A, by rotating in the direction of arrow C. At this time, when the outer periphery of the blade portion Wg of the screw 38 is opened radially outward, the toner T between the blades is released radially outward due to centrifugal force, making it impossible to stably deliver the toner T.

[0051] Therefore, in this embodiment, in the portion of the toner delivery section Ar1 opposite to the screw 38, an induction wall 51 is formed along the screw 38, covering the lower portion of the outer periphery of the blade portion Wg of the screw 38. The induction wall 51 is formed protrudingly from the rear plate Pr to the front plate Pf, covering the outer periphery of the blade portion Wg of the screw 38 with an arc-shaped surface Sa, and induces the toner T along the axial direction of the screw 38.

[0052] However, when the induction wall 51 is integrally formed between the rear plate Pr and the front plate Pf, the membrane Fma cannot reliably push the toner T around the toner outlet h1 into the toner outlet h1 even though it rotates with the rotation of the screw 38.

[0053] Therefore, in this embodiment, by cutting off the portion of the inducing wall 51 adjacent to the toner outlet h1 and corresponding to the membrane Fma, an inclined surface Sb with a rectangular shape is formed, which serves as a guiding portion to guide the toner T to the toner outlet h1. This inclined surface Sb is formed by tilting the edge of the side plate Ps2 side of the toner outlet h1 in the base plate Pb downward toward the side plate Ps1 side.

[0054] Next, the operation of the toner holder 17i will be explained.

[0055] When the toner T in the image forming unit 16i is reduced as an image is formed in the printer 10, driving force is transmitted from the drive source to the connecting parts Cna and Cnb, the screw 38 and the stirring device 39 rotate, and the membranes Fma and Fmb rotate.

[0056] Therefore, the toner T in the toner storage section Ar2 is conveyed by the membrane Fmb toward the screw 38 in the direction of arrow E, and is conveyed along the screw 38 toward the toner outlet h1 in the direction of arrow A. When it reaches the toner outlet h1, the membrane Fma is pushed into the toner outlet h1.

[0057] At this time, an inclined surface Sb is formed on the induction wall 51 that descends toward the toner outlet h1. Therefore, the toner T is reliably pushed into the toner outlet h1 and smoothly discharged out of the housing Ct and supplied to the image forming unit 16i.

[0058] Thus, in this embodiment, the inclined surface Sb is formed by cutting off the portion of the induction wall 51 along the screw 38 that corresponds to the membrane Fma. Therefore, without scraping against the induction wall 51, the toner T can be reliably pushed into the toner outlet h1 through the membrane Fma.

[0059] Therefore, the toner T can be discharged smoothly.

[0060] In this embodiment, printer 10 is described; however, the present invention can be applied to image forming apparatuses such as copiers, fax machines, and multifunction printers.

[0061] Furthermore, the toner outlet h1, which serves as the developer outlet, can be formed not only at the end of the housing Ct, i.e., the upper end of the bottom plate Pb, but also at the axial center of the housing Ct. In this case, the membrane Fma, which serves as the pushing member, and the inclined surface Sb, which serves as the guide, are formed on both axial sides in the discharge direction.

[0062] Furthermore, the present invention is not limited to the described embodiments, and various modifications can be made according to the spirit of the present invention, without excluding them from the scope of the present invention.

Claims

1. A developer container characterized by comprising: The developer container has: (a) a housing that contains a developer, formed with a developer discharge port for discharging the developer; (b) a conveyance screw rotatably provided in the housing, which conveys the developer in the axial direction toward the developer discharge port in conjunction with rotation; (c) an inducing wall provided along the conveyance screw, which induces the developer in the axial direction of the conveyance screw; and (d) a push-in member that is attached to the conveyance screw, rotates together with the conveyance screw, and pushes the developer into the developer discharge port, and (e) a sloped surface that guides the developer to the developer discharge port is formed at a portion of the inducing wall that corresponds to the push-in member and is adjacent to the developer discharge port.

2. The developer container according to claim 1, wherein the guide portion formed in the inducing wall is a sloped surface that slopes downward toward the developer discharge port.

3. The developer container according to claim 1 or 2, wherein the developer discharge port is formed at one end side in the axial direction of the housing, the housing is provided so as to slope in such a manner that the one end side in which the developer discharge port is formed is higher than the other end side in the axial direction.

4. The developer container according to claim 1 or 2, wherein (a) a developer storage portion that stores the developer is formed adjacent to the inducing wall in the housing, (b) a storage developer conveyance member that conveys the developer toward the inducing wall is provided in the developer storage portion.

5. The developer container according to claim 4, wherein the storage developer conveyance member has a shaft member that extends in parallel with the conveyance screw so as to be rotatably provided, and a push-out member that is attached to the shaft member, rotates together with the shaft member, and pushes the developer out toward the inducing wall.

6. An image forming apparatus that has the developer container according to any one of claims 1 to 5.

Images