Image forming apparatus

An image forming apparatus includes a toner case, an opening/closing member, a lever member, a drive transmission mechanism, and a biasing member. The toner case is attached to an apparatus main body. The opening/closing member opens and closes a toner discharge outlet formed in the toner case. The lever member is operated between a first operation position and a second operation position for the opening/closing member to be moved to a closing position corresponding to the first operation position or to an opening position corresponding to the second operation position. The drive transmission mechanism transmits, to the opening/closing member, a driving force input by operation of the lever member. The biasing member biases the opening/closing member toward the closing position when the lever member is at the first operation position, and biases the opening/closing member toward the opening position when the lever member is at the second operation position.

INCORPORATION BY REFERENCE

This application is based upon and claims the benefit of priority from the corresponding Japanese Patent Application No. 2014-132967 filed on Jun. 27, 2014, the entire contents of which are incorporated herein by reference.

BACKGROUND

The present disclosure relates to an image forming apparatus that can open and close a toner discharge outlet through which toner is discharged from a toner case to an apparatus main body.

A developing device is installed in an image forming apparatus such as a copier, a printer or the like that forms an image on a print sheet by the electrophotography. The toner inside the developing device is decreased as the developing device performs the developing. As a result, the image forming apparatus is configured such that a toner case storing toner can be attached to and detached from the image forming apparatus. The toner is supplied from the toner case to the developing device in the state where the toner case is attached to the image forming apparatus. The toner case includes a toner discharge outlet and an opening/closing member (shutter member), wherein the toner is discharged from the toner discharge outlet to outside, and the opening/closing member is configured to open and close the toner discharge outlet. Conventionally, an operation lever, which is attached to the toner case or the apparatus main body, is operated so as to displace the opening/closing member between the opening position and the closing position, thereby allowing the toner discharge outlet to be opened and closed.

SUMMARY

An image forming apparatus according to an aspect of the present disclosure includes a toner case, an opening/closing member, a lever member, a drive transmission mechanism, and a biasing member. The toner case is attached to an apparatus main body. The opening/closing member is configured to open and close a toner discharge outlet formed in the toner case. The lever member is configured to be operated between a first operation position and a second operation position for the opening/closing member to be moved to a closing position corresponding to the first operation position or to an opening position corresponding to the second operation position. The drive transmission mechanism is configured to transmit, to the opening/closing member, a driving force that is input by an operation of the lever member. The biasing member is configured to bias the opening/closing member toward the closing position when the lever member is at the first operation position, and bias the opening/closing member toward the opening position when the lever member is at the second operation position.

DETAILED DESCRIPTION

The following describes an embodiment of the present disclosure with reference to the attached drawings. It should be noted that the following description is an example of a specific embodiment of the present disclosure and should not limit the technical scope of the present disclosure. It is noted that for the sake of explanation, an up-down direction6is defined based on the state (the state shown inFIG. 1) where an image forming apparatus10in an embodiment of the present disclosure is installed on a flat surface. In addition, a front-rear direction7is defined on the supposition that the left side on the plane ofFIG. 1is the front side (front-surface side) of the image forming apparatus10. Furthermore, a left-right direction8(a direction perpendicular to the plane ofFIG. 1) is defined based on the image forming apparatus10ofFIG. 1viewed from the front side. Accordingly, the front side on the plane ofFIG. 1is the right side, and the depth side on the plane ofFIG. 1is the left side.

The image forming apparatus10is an image forming apparatus that includes at least a print function. As shown inFIG. 1, the image forming apparatus10is a so-called tandem color printer. The image forming apparatus10prints an image on a sheet of print paper by using a developer that contains toner. It is noted that the image forming apparatus10may be any apparatus as far as it has the print function. For example, the image forming apparatus10may be a multifunction peripheral having a plurality of functions including the print function, or an image forming apparatus such as a FAX apparatus or a copier. Of course, the image forming apparatus10may be an apparatus for forming a monochrome image, instead of an apparatus for forming a color image.

As shown inFIG. 1, the image forming apparatus10includes, as major components, four image forming portions21, an intermediate transfer unit22, a sheet feed device25, a fixing device26, a secondary transfer device27, an exposure device24, and four toner containers50(50A-50D). These components are attached to an apparatus main body28that is a housing constituting an external frame (not shown), an internal frame (not shown) and the like of the image forming apparatus10. It is noted that the toner containers50of the image forming apparatus10are an example of the toner case.

The four image forming portions21are disposed below the intermediate transfer unit22in the apparatus main body28. The image forming portions21are aligned along the front-rear direction7. The image forming portions21execute an image forming process to form an image on a print sheet based on the so-called electrophotography. Specifically, the image forming portions21print an image on a print sheet based on the image data input from outside via a network communication portion (not shown). Each of the image forming portions21includes a photoconductor drum11, a charging device (not shown), a developing device12, a primary transfer device13, and the like. The image forming portions21form toner images respectively on the photoconductor drums11, and transfer the toner images to a transfer belt23included in the intermediate transfer unit22by overlaying the toner images onto the belt in sequence. The transfer belt23moves in a direction indicated by the arrow19, and the toner images are transferred in sequence to the transfer belt23while it is moving. In the example shown inFIG. 1, in order from the downstream side in the movement direction of the transfer belt23(the direction indicated by the arrow19), the image forming portions21for black, cyan, magenta and yellow are disposed in a row in the apparatus main body28.

The intermediate transfer unit22is disposed above the image forming portions21. At opposite ends of the intermediate transfer unit22in the front-rear direction7, a driving pulley31and a driven pulley32are provided. The transfer belt23is suspended between and supported by the driving pulley31and the driven pulley32. As such, the transfer belt23extends in the front-rear direction7in the state where the belt surface extends horizontally. Supported by the driving pulley31and the driven pulley32, the transfer belt23can move (run) in the direction indicated by the arrow19, with its surface being in contact with the surfaces of the photoconductor drums11. The transfer belt23is a belt formed in the shape of an endless loop and made of rubber, urethane or other material.

The secondary transfer device27transfers, from the transfer belt23to a print sheet, a color toner image composed of the toner images of the plurality of colors. The print sheet with the color toner image transferred thereon is conveyed to the fixing device26. The fixing device26fixes the color toner image transferred to the print sheet, to the print sheet by heat. The fixing device26includes a heating roller26A heated to a high temperature, and a pressure roller26B disposed to face the heating roller26A. In the fixing device26, the print sheet is conveyed while being nipped by a predetermined biasing force at a nip portion between the heating roller26A and the pressure roller26B. This allows the color toner image to be fused and adhered to the print sheet. Subsequently, the print sheet is discharged onto a sheet discharge tray29provided on an upper part of the apparatus main body28.

The image forming apparatus10may have a configuration where the transfer belt23is used as a conveyance belt, and the toner images are overlaid directly on a print sheet that is being conveyed on the conveyance belt. In addition, the image forming apparatus10may have a configuration where an intermediate transfer member in the shape of a roller is used in place of the transfer belt23.

The four toner containers50(50A-50D) are disposed above the intermediate transfer unit22. Inside the apparatus main body28, the four toner containers50are aligned in a row along the transfer belt23in the front-rear direction7. The toner containers50are configured to supply toner to the developing devices12of corresponding colors.

As shown inFIG. 2, an attachment portion34to which the plurality of toner containers50are attached is provided in the apparatus main body28. Specifically, the attachment portion34is provided above the intermediate transfer unit22. A top cover33provided on the upper part of the apparatus main body28is supported so as to be opened and closed around a spindle33A of the apparatus main body28(seeFIG. 1). When the top cover33is pivoted upward (in the opening direction), the attachment portion34, to which the toner containers50are attached, is exposed. The attachment portion34is integrally formed with the upper part of the intermediate transfer unit22, and the toner containers50are attached to be stored in the attachment portion34. It is noted that the attachment portion34is not limited to the one integrally formed with the upper part of the intermediate transfer unit22, but may be attached to the apparatus main body28as a member independent of the intermediate transfer unit22.

The toner containers50store toner of different colors that correspond to the colors of the image forming portions21. Specifically, the toner containers50(50A-50D) store toner of black, cyan, magenta, and yellow, respectively. As shown inFIG. 1andFIG. 2, among the four toner containers50, the toner container50A positioned on the most rear side is a large-capacity type and can store a larger amount of toner than the other toner containers50B-50D. The toner container50A stores black toner. The toner containers50B-50D have the same shape and capacity. The toner container50B stores cyan toner, the toner container50C stores magenta toner, and the toner container50D stores yellow toner.

The following describes the configuration of the toner containers50. It is noted here that the large-capacity-type toner container50A and the other toner containers50B-50D have the same configuration except for the size of the toner storing part. In addition, the toner containers50B-50D have the same configuration except for the arrangement position. As a result, in the following description, the toner containers50A-50D are described as a toner container50.

The toner container50stores toner that is to be supplied to the developing device12. As shown inFIG. 3toFIG. 5, the toner container50includes a housing51, a toner discharge outlet52(seeFIG. 4), an opening/closing mechanism53(seeFIG. 4), an operation portion54, and a cover72. The opening/closing mechanism53is an example of the opening/closing member of the present disclosure. The housing51is attached to the attachment portion34of the image forming apparatus10. Toner is stored in the housing51. As shown inFIG. 4, the housing51has the toner discharge outlet52. The toner discharge outlet52is formed in the bottom of the housing51at the right end thereof. In addition, as shown inFIG. 5, the operation portion54is provided on the housing51so as to be operated by the user.

As shown inFIG. 2andFIG. 3, the apparatus main body28includes support plates42and43to which the housing51is attached. The support plates42and43are formed plate-like and extend in the front-rear direction7. The support plates42and43are disposed to face each other in the attachment portion34. As shown inFIG. 2, the support plate42is erected at the left end of the attachment portion34. As shown inFIG. 3, the support plate43is erected at the right end of the attachment portion34. The support plates42and43support opposite ends of the four toner containers50respectively.

On a left side surface43A (seeFIG. 3) of one side (the left side) of the support plate43, a plurality of groove-like container guides45are formed to extend diagonally upward. The container guides45are formed groove-like by recessing the left side surface43A of the support plate43in the thickness direction. In addition, an end portion of each container guide on the upper part side of the support plate43is formed to spread upward. The right end portion of the housing51is attached to the support plate43by being guided by the container guide45diagonally downward from the upper end of the support plate43.

The housing51is made of a resin material, and is, as shown inFIG. 3, formed in the shape of a box that is long in the left-right direction8. That is, the longitudinal direction of the housing51matches the left-right direction8of the image forming apparatus10shown inFIG. 1.

As shown inFIG. 3, the housing51includes a container main body55and a lid portion56. The container main body55is formed in the shape of a box which has a bottom and whose upper part is opened. The lid portion56closes the upper opening portion of the container main body55. Inside the container main body55, a stirring paddle (not shown) and a screw portion58(seeFIG. 8) are provided, wherein the stirring paddle is configured to stir the toner, and the screw portion58is configured to convey the toner to the toner discharge outlet52.

As shown inFIG. 5, the cover72is provided in such a way as to cover a right side wall55B of the container main body55. The side wall55B is provided with a toner filling port59that allows the toner to be filled into the housing51. The toner filling port59is closed by a plug member60.

As shown inFIG. 4,FIG. 5, andFIG. 8, the toner discharge outlet52is formed in the toner container50. Specifically, the toner discharge outlet52is formed in the bottom of the container main body55at the right end thereof. The toner discharge outlet52is formed in such a way as to pass through the bottom wall of the container main body55downward. Specifically, as shown inFIG. 8, a protruding portion55A is formed at the right end of the container main body55, wherein the protruding portion55A is in an approximate shape of a cylinder protruding and extending rightward. The toner discharge outlet52is formed in such a way as to pass through the circumferential wall of the protruding portion55A downward.

The opening/closing mechanism53opens and closes the toner discharge outlet52, and as shown inFIG. 8, includes a cylinder61, an opening62, a seal member63, and a second coupling portion79. The cylinder61is formed in the shape of a cylinder and inserted in the protruding portion55A that is provided at the right end of the container main body55. The right end portion of the cylinder61is closed. In addition, the right end portion of the cylinder61is integrally formed with the second coupling portion79that is described below. The opening62is formed in a side surface (lower surface) of the cylinder61. Furthermore, the seal member63is provided on an inner wall surface of the protruding portion55A at the peripheral of the toner discharge outlet52. The seal member63is provided for prevention of scattering of toner.

A bearing64is formed inside the cylinder61at the right end thereof. An end of the screw portion58is supported by the bearing64such that the screw portion58can rotate in the cylinder61.

The cylinder61is attached so as to be rotatable with respect to the protruding portion55A. When a rotational force is input to the second coupling portion79, the cylinder61is rotated. When the cylinder61rotates and the opening62of the cylinder61overlaps with the toner discharge outlet52, the toner discharge outlet52is opened as shown inFIG. 8. Hereinafter, the position of the cylinder61(the position shown inFIG. 8) that allows the toner discharge outlet52to be opened is referred to as an “opening position”. When the cylinder61is rotated to the opening position, toner in the housing51is discharged from the toner discharge outlet52to outside smoothly. On the other hand, when the cylinder61rotates and the circumferential wall of the cylinder61except for the opening62overlaps with the toner discharge outlet52, the toner discharge outlet52is closed by the circumferential wall of the cylinder61. Hereinafter, the position of the cylinder61where the toner discharge outlet52is closed is referred to as a “closing position”. When the cylinder61is rotated to the closing position, the toner discharge outlet52is completely closed.

With the rotation of the second coupling portion79, the cylinder61is displaced between the opening position and the closing position. That is, the toner discharge outlet52is opened and closed with the rotation of the cylinder61. When the toner container50is attached to the attachment portion34, the second coupling portion79is coupled with a drive transmission mechanism76(seeFIG. 9toFIG. 12C) that is provided in the apparatus main body28(specifically, in the attachment portion34). This allows the second coupling portion79to receive the rotational force from the drive transmission mechanism76. It is noted that the drive transmission mechanism76and the second coupling portion79are described in detail below.

When the toner container50is attached to the attachment portion34, the toner discharge outlet52is disposed in front of a communication port (not shown) that is formed in the intermediate transfer unit22, and becomes in close contact with the communication port. The toner is supplied from the communication port to the developing device12via a conveyance path (not shown). The attachment position of the toner container50in the attachment portion34is determined so that the above-described positional relationship is satisfied. The operation portion54is used to open and close the toner discharge outlet52in the state where the toner container50is attached to the attachment portion34. As shown inFIG. 5, the operation portion54is provided at the right end of the container main body55. The operation portion54includes a shaft66and a lever67(an example of the lever member). The shaft66is rotatably supported by the container main body55. The lever67is fixed to the shaft66and extends from the shaft66.

The shaft66includes a shaft core that extends rightward from the right end of the housing51. The lever67is configured to integrally pivot with the shaft66around the shaft core of the shaft66. In the present embodiment, the operation portion54can pivot between a first operation position (the attitude shown inFIG. 6A) and a second operation position (the attitude shown inFIG. 6B), wherein the lever67is inclined frontward in the first operation position, and is inclined rearward in the second operation position. In the present embodiment, with the operation of the lever67between the first operation position and the second operation position, the cylinder61of the opening/closing mechanism53is moved to the closing position corresponding to the first operation position, or to the opening position corresponding to the second operation position. Here, the first operation position is an attitude corresponding to the closing position of the cylinder61. Specifically, when the cylinder61is to be maintained at the closing position or displaced to the closing position, the lever67is disposed at the first operation position. On the other hand, the second operation position is an attitude corresponding to the opening position of the cylinder61. Specifically, when the cylinder61is to be maintained at the opening position or displaced to the opening position, the lever67is disposed at the second operation position.

In addition, a lock member71is provided at the right end of the container main body55. The lock member71locks the operation portion54and the opening/closing mechanism53for the purpose of preventing them from mulfunctioning. That is, the lock member71locks the operation portion54so as to restrict the operation of the operation portion54. Furthermore, the lock member71locks the opening/closing mechanism53so as to restrict the opening/closing operation of the opening/closing mechanism53. The lock member71is integrally formed with a releasing portion71A that is claw-like and projecting rightward. It is noted that since the lock member71is not a major component of the present disclosure, detailed description of the lock member71is omitted.

As shown inFIG. 4andFIG. 5, the cover72is attached to the side wall55B at the right end of the container main body55. The cover72is attached in such a way as to cover the base part of the lever67, the lock member71and the like. An arc-shaped slit72C is formed in an upper wall72A of the cover72, and an upper end of the lever67extends out upward from the slit72C to be exposed to outside. A right side wall72B of the cover72has an opening72D, and a first coupling portion78described below extends out rightward from the opening72D to be exposed to outside. In addition, on the right side surface72B, a guide groove72E is formed, wherein the guide groove72E extends vertically and is opened downward. As shown inFIG. 7A, the releasing portion71A of the lock member71is exposed from the cover72at the guide groove72E. It is noted that the second coupling portion79of the cylinder61is not covered with the cover72.

The cover72includes a block-like positioning projection73projecting rightward from the right end of the container main body55. The positioning projection73has a width which allows it to be fitted in the container guide45(seeFIG. 3), the width being slightly smaller than the groove width of the container guide45. This enables the positioning projection73to be attached to the container guide45. Specifically, as shown inFIG. 3, when the positioning projection73is fitted in the container guide45and guided by the container guide45diagonally downward, the housing51is attached to the support plate43.

Here,FIG. 9shows the outer appearance of the support plate43.FIG. 10A,FIG. 10B, andFIG. 11are expanded views of the drive transmission mechanism76.FIG. 12AtoFIG. 12Care diagrams for explaining the operation of the drive transmission mechanism76. It is noted thatFIG. 9shows the support plate43viewed from a left side surface43A.FIG. 10AandFIG. 10Bare expanded views of the peripheral of one container guide45shown inFIG. 9.FIG. 11shows the support plate43viewed from a right side surface43B.FIG. 12Ashows the state where the lever67is at the first operation position.FIG. 12Bshows the state where the lever67is at an intermediate position between the first operation position and the second operation position.FIG. 12Cshows the state where the lever67is at the second operation position.

As shown inFIG. 9, the drive transmission mechanism76is provided on the right side surface43B of the support plate43. The lower part of each container guide45of the support plate43is branched into a first groove portion45A and a second groove portion45B. An elongated projection portion46is formed between the first groove portion45A and the second groove portion45B, wherein the elongated projection portion46extends along the first groove portion45A and the second groove portion45B.

When the cover72is guided diagonally downward in the attachment direction by the container guide45, the elongated projection portion46is inserted into the guide groove72E of the cover72. Subsequently, the upper part of the elongated projection portion46abuts on the releasing portion71A of the lock member71, and pushes up the lock member71. In this way, when the toner container50is attached to the support plate43, the lock member71abuts on the elongated projection portion46and operates in the lock release direction. This allows the lock state of the operation portion54and the opening/closing mechanism53by the lock member71to be released.

As shown inFIG. 10A,FIG. 10B, andFIG. 11, the apparatus main body28is provided with the drive transmission mechanism76. The drive transmission mechanism76is provided on the support plate43constituting the apparatus main body28. In the present embodiment, four drive transmission mechanisms76are provided in correspondence with the four toner containers50. The drive transmission mechanisms76are provided in alignment in the front-rear direction7on the right side surface43B of the support plate43.

The drive transmission mechanism76is configured such that, when the lever67of the operation portion54is operated and an operation driving force (driving force) is input in the state where the toner container50is attached to the support plate43, the drive transmission mechanism76transmits the operation driving force to the opening/closing mechanism53.

The drive transmission mechanism76includes a first rotation portion74(input transmission portion), an intermediate rotation portion81(intermediate transmission portion), and a second rotation portion75(output transmission portion). The first rotation portion74is a portion that receives the operation driving force input from the operation portion54when the lever67of the operation portion54is operated. Upon receiving the operation driving force, the first rotation portion74transmits the operation driving force to the intermediate rotation portion81. The intermediate rotation portion81is a portion that receives, from the first rotation portion74, the operation driving force input by the operation of the lever67of the operation portion54and transmits the received operation driving force to the second rotation portion75. The second rotation portion75is a portion that receives the operation driving force from the intermediate rotation portion81and outputs (transmits) the operation driving force to an external device (the opening/closing mechanism53). In other words, the second rotation portion75receives the operation driving force transmitted from the first rotation portion74via the intermediate rotation portion81, and outputs (transmits) the operation driving force to an external device (the opening/closing mechanism53). The first rotation portion74is configured to rotate upon receiving the operation driving force. The intermediate rotation portion81is configured to rotate in conjunction with the first rotation portion74. The second rotation portion75is configured to rotate in conjunction with the first rotation portion74and the intermediate rotation portion81.

The first rotation portion74is disposed at the lower end of the first groove portion45A of the container guide45, and is rotatably supported by the support plate43. On the other hand, the second rotation portion75is disposed at the lower end of the second groove portion45B, and is rotatably supported by the support plate43. The first rotation portion74and the second rotation portion75are separated from each other and are not configured to directly transmit the driving force to each other. The intermediate rotation portion81is provided between the first rotation portion74and the second rotation portion75, and the intermediate rotation portion81is rotatably supported by the support plate43. The intermediate rotation portion81is connected so as to be able to transmit a driving force to the first rotation portion74and the second rotation portion75.

As shown inFIG. 11, the first rotation portion74is a rotator and includes a first gear portion74A. The second rotation portion75is a rotator and includes a second gear portion75A (gear portion). The intermediate rotation portion81is a rotator and includes an intermediate gear portion81A (gear portion) that meshes with the first gear portion74A and the second gear portion75A respectively. The first gear portion74A is integrally formed with the first rotation portion74. The intermediate gear portion81A is integrally formed with the intermediate rotation portion81. The second gear portion75A is integrally formed with the second rotation portion75. As a result, when the first rotation portion74rotates in the state where the first gear portion74A and the intermediate gear portion81A mesh with each other and the intermediate gear portion81A and the second gear portion75A mesh with each other, the intermediate rotation portion81rotates reversely with respect to the rotational direction of the first rotation portion74, and the second rotation portion75rotates in the same direction as the first rotation portion74.

In the present embodiment, the first gear portion74A and the second gear portion75A are set such that the first rotation portion74and the second rotation portion75have the same rotation angle. Specifically, the first gear portion74A and the second gear portion75A have the same number of teeth and the same pitch. For example, the first gear portion74A and the second gear portion75A are set such that, when the first rotation portion74rotates 45 degrees together with the lever67, the second rotation portion75also rotates 45 degrees.

In addition, as shown inFIG. 11, the drive transmission mechanism76includes a spring77(biasing member). The spring77biases the opening/closing mechanism53toward the closing position via the second rotation portion75when the lever67is positioned at the first operation position in the state where the toner container50is attached to the attachment portion34. Furthermore, the spring77biases the opening/closing mechanism53toward the opening position via the second rotation portion75when the lever67is positioned at the second operation position in the state where the toner container50is attached to the attachment portion34.

The spring77intervenes between the intermediate rotation portion81and the second rotation portion75. The spring77is, for example, a coil spring. In the present embodiment, the spring77is attached in such a way as to be stretched and compressed with the rotation of the intermediate rotation portion81and the second rotation portion75in response to an operation of the lever67. Specifically, the intermediate rotation portion81includes a first support piece81B projecting outward in the radial direction from the outer circumferential surface thereof. The first support piece81B is a portion to which one end portion of the spring77is fixed. That is, the first support piece81B supports one end of the spring77. Since the first support piece81B pivots as the intermediate rotation portion81rotates, when the intermediate rotation portion81rotates, the position of the first support piece81B supporting the spring77changes. The second rotation portion75includes a second support piece75C projecting outward in the radial direction from the outer circumferential surface thereof. The second support piece75C is a portion to which the other end portion of the spring77is fixed. That is, the second support piece75C supports the other end of the spring77. Since the second support piece75C pivots as the intermediate rotation portion81rotates, when the intermediate rotation portion81rotates, the position of the second support piece75C supporting the spring77changes.

As shown inFIG. 11, the spring77is attached between the first support piece81B and the second support piece75C. The spring77always generates a spring force in the compression direction, and is a so-called tension spring. In the present embodiment, as shown inFIG. 12B, when the first support piece81B and the second support piece75C are disposed on a line segment connecting between the center of the intermediate rotation portion81and the center of the second rotation portion75, the spring forces of the spring77balance with each other, and the intermediate rotation portion81and the second rotation portion75maintain the stationary state. In this state, the spring77is maximally stretched. The positions of the lever67and the cylinder61when the spring forces of the spring77balance with each other are determined in advance. Specifically, in this state, the lever67is positioned at an intermediate position between the first operation position and the second operation position, and the cylinder61is positioned at an intermediate position between the opening position and the closing position. Here, the intermediate position of the lever67is an example of the predetermined position in an operation range of the lever67except for the first operation position and the second operation position.

In the state shown inFIG. 12B, when the lever67is operated from the intermediate position toward the first operation position, the balance of the spring77is released. Specifically, with the operation of the lever67, the first rotation portion74allows the intermediate rotation portion81to rotate clockwise, and the intermediate rotation portion81allows the second rotation portion75to rotate counterclockwise. In this case, as shown inFIG. 12A, the spring77applies a force in the compression direction in such a way as to further allow the intermediate rotation portion81to rotate clockwise and further allow the second rotation portion75to rotate counterclockwise. At this time, even if no operation driving force is input to the lever67after it is operated from the intermediate position, the intermediate rotation portion81and the second rotation portion75are rotated only by the force of the spring77. This allows the rotation of the second rotation portion75to be transmitted to the cylinder61, and the cylinder61is displaced to the opening position by the biasing force of the spring77in a reliable manner.

On the other hand, in the state shown inFIG. 12B, when the lever67is operated from the intermediate position toward the second operation position, the balance of the spring77is released. Specifically, with the operation of the lever67, the first rotation portion74allows the intermediate rotation portion81to rotate counterclockwise, and the intermediate rotation portion81allows the second rotation portion75to rotate clockwise. In this case, as shown inFIG. 12C, the spring77applies a force in the compression direction in such a way as to further allow the intermediate rotation portion81to rotate counterclockwise and further allow the second rotation portion75to rotate clockwise. At this time, even if no operation driving force is input to the lever67after it is operated from the intermediate position, the intermediate rotation portion81and the second rotation portion75are rotated only by the force of the spring77. This allows the rotation of the second rotation portion75to be transmitted to the cylinder61, and the cylinder61is displaced to the closing position by the biasing force of the spring77in a reliable manner.

As shown inFIG. 4andFIG. 5, the operation portion54includes the first coupling portion78that is rotated when the lever67is operated. The first coupling portion78is integrally formed with the right end of the shaft66. The first coupling portion78is formed in the shape of a plate that projects rightward from the right end of the shaft66. The first coupling portion78extends in the attachment direction (namely, diagonally downward) in which the cover72is guided by the container guide45when the housing51is attached to the support plate43. The first coupling portion78is coupled with the first rotation portion74of the drive transmission mechanism76in the state where the toner container50is attached to the container guide45of the support plate43. That is, the first coupling portion78is coupled with the first rotation portion74in the state where the toner container50is attached. With this configuration, the operation driving force that is input when the operation portion54is operated is transmitted to the first rotation portion74.

As shown inFIG. 10AandFIG. 10B, a first coupling groove74B is formed in the first rotation portion74of the drive transmission mechanism76such that the first coupling portion78of the toner container50is coupled with the first coupling groove74B. The first coupling groove74B extends straight at least in part. On the other hand, the first coupling portion78is shaped so as to be fitted in the first coupling groove74B. That is, the groove width of the first coupling groove74B is approximately the same as the thickness of the first coupling portion78. When the housing51is attached to the apparatus main body28, the first coupling portion78is inserted into the first coupling groove74B and is coupled therewith so as to be integrally rotatable with the first rotation portion74.

As shown inFIG. 4andFIG. 5, the opening/closing mechanism53of the toner container50includes the second coupling portion79that integrally rotates with the cylinder61. The second coupling portion79is integrally formed with the right end of the cylinder61. The second coupling portion79projects rightward from the right end of the cylinder61. The second coupling portion79is formed in a shape of a hook in a cross section taken along a line that is perpendicular to the axis direction of the cylinder61. The second coupling portion79receives the operation driving force from the second rotation portion75of the drive transmission mechanism76. The second coupling portion79is coupled with the second rotation portion75of the drive transmission mechanism76in the state where the toner container50is attached to the container guide45of the support plate43. That is, the second coupling portion79is coupled with the second rotation portion75in the state where the toner container50is attached. This enables the operation driving force to be transmitted to the second coupling portion79via the first rotation portion74, the intermediate rotation portion81and the second rotation portion75.

The second coupling portion79extends in the attachment direction (namely, diagonally downward) in which the cover72is guided by the container guide45when the housing51is attached to the support plate43. The second coupling portion79is larger in thickness than the first coupling portion78.

As shown inFIG. 10AandFIG. 10B, a second coupling groove75B is formed in the second rotation portion75of the drive transmission mechanism76such that the second coupling portion79of the toner container50is coupled with the second coupling groove75B. The second coupling groove75B extends straight at least in part. On the other hand, the second coupling portion79(seeFIG. 4andFIG. 5) is shaped so as to be fitted in the second coupling groove75B. That is, the groove width of the second coupling groove75B is approximately the same as the thickness of the second coupling portion79. As a result, the second coupling groove75B and the first coupling groove74B are different in groove width. When the housing51is attached to the support plate43, the second coupling portion79is inserted into the second coupling groove75B, and is coupled therewith so as to be integrally rotatable with the second rotation portion75. The opening/closing mechanism53is configured such that the second coupling portion79and the second rotation portion75integrally rotate with each other, thereby the cylinder61is rotated in such a way as to open and close the toner discharge outlet52.

Next, description is given of the attachment/detachment operation of the toner container50with respect to the apparatus main body28.

Before the toner container50is attached to the apparatus main body28, the toner discharge outlet52is closed by the cylinder61, and the operation portion54and the opening/closing mechanism53are in the lock state by the lock member71. At this time, as shown inFIG. 7A, the first coupling portion78and the second coupling portion79extend in the attachment direction (namely, diagonally downward) in which the cover72is guided by the container guide45. In addition, the lever67is positioned at the first operation position, and the cylinder61is positioned at the closing position.

Furthermore, as shown inFIG. 10A, before the toner container50is attached to the apparatus main body28, the first coupling groove74B of the first rotation portion74and the second coupling groove75B of the second rotation portion75in the drive transmission portion76are extending in the extension direction of the container guide45(namely, the attachment direction in which the cover72is guided).

When the toner container50is attached to the support plate43, the cover72is inserted into the container guide45of the support plate43. The cover72is then guided diagonally downward by the container guide45. The first coupling portion78of the toner container50is guided by the first groove portion45A, and the second coupling portion79is guided by the second groove portion45B. Subsequently, the first coupling portion78is coupled with the first coupling groove74B of the first rotation portion74, and the second coupling portion79is coupled with the second coupling groove75B of the second rotation portion75.

In addition, while the cover72is guided by the container guide45, the upper end of the elongated projection portion46abuts on the releasing portion71A of the lock member71and pushes up the lock member71. This allows the operation portion54and the opening/closing mechanism53of the toner container50to be released from the lock state in the state where the first coupling portion78is coupled with the first rotation portion74and the second coupling portion79is coupled with the second rotation portion75.

Next, the toner discharge outlet52is opened by pivoting the lever67of the operation portion54. Specifically, the lever67is pivoted from the first operation position (seeFIG. 7A) toward the second operation position (seeFIG. 7B). When the lever67of the operation portion54is pivoted in the state where the toner container50is attached to the support plate43, the operation driving force is input to the first coupling portion78via the shaft66of the operation portion54. This allows the shaft66and the first coupling portion78to be integrally rotated with the lever67clockwise (seeFIG. 7B). That is, the first coupling portion78is rotated by the same angle as the pivoting angle of the lever67.

The first coupling portion78is integrally rotated with the first rotation portion74of the drive transmission portion76because the first coupling portion78is coupled with the first rotation portion74. As shown inFIG. 9, in the apparatus main body28side, the first gear portion74A of the first rotation portion74meshes with the intermediate gear portion81A of the intermediate rotation portion81, and the intermediate gear portion81A meshes with the second gear portion75A of the second rotation portion75. This allows the operation driving force to be transmitted from the first rotation portion74to the second rotation portion75via the intermediate rotation portion81, and the second rotation portion75rotates in the same rotation direction as the first rotation portion74.

The second rotation portion75is integrally rotated with the second coupling portion79of the toner container50because the second rotation portion75is coupled with the second coupling portion79. With the rotation of the second coupling portion79, the cylinder61integrally rotates with the second coupling portion79toward the opening position.

At this time, with the pivoting operation of the lever67, the spring77is gradually stretched, and the user feels a burden when operating the lever67. However, after the lever67passes the intermediate position between the first operation position and the second operation position, the lever67is automatically pivoted to the second operation position by the force of the spring77in the compression direction without operation of the lever67. As shown inFIG. 12C, in the state where the lever67has reached the second operation position, the second rotation portion75receives, from the spring77, a force that allows the cylinder61to rotate toward the opening position. As a result, if a portion from the first gear portion74A to the second gear portion75A has a gear loss, the second rotation portion75is disposed at a position corresponding to the opening position without being affected by the gear loss. Consequently, the toner discharge outlet52is displaced to the opening position in a reliable manner. In addition, since the user does not need to operate the lever67to the second operation position, the operability of the lever67is improved. Furthermore, since the user can clearly recognize the switching between the opening and closing of the toner discharge outlet52, it is possible to provide an excellent operation feeling.

When the toner discharge outlet52is closed, the lever67is pivoted from the second operation position (seeFIG. 7B) toward the first operation position (seeFIG. 7A). This pivoting allows the shaft66and the first coupling portion78to be integrally rotated with the lever67counterclockwise (seeFIG. 7A). That is, the first coupling portion78is rotated by the same angle as the pivoting angle of the lever67.

As shown inFIG. 9, in the apparatus main body28side, the operation driving force is transmitted from the first rotation portion74to the second rotation portion75via the intermediate rotation portion81, and the second rotation portion75rotates in the same rotation direction as the first rotation portion74. Here, since the second rotation portion75is coupled with the second coupling portion79of the toner container50, the second coupling portion79integrally rotates with the second rotation portion75. With the rotation of the second coupling portion79, the cylinder61integrally rotates with the second coupling portion79toward the closing position.

At this time, with the pivoting operation of the lever67, the spring77is gradually stretched, and the user feels a burden when operating the lever67. However, after the lever67passes the intermediate position between the first operation position and the second operation position, the lever67is automatically pivoted to the first operation position by the force of the spring77in the compression direction without operation of the lever67. As shown inFIG. 12A, in the state where the lever67has reached the first operation position, the second rotation portion75receives, from the spring77, a force that allows the cylinder61to rotate toward the closing position. As a result, if a portion from the first gear portion74A to the second gear portion75A has a gear loss, the second rotation portion75is disposed at a position corresponding to the closing position without being affected by the gear loss. Consequently, the toner discharge outlet52is displaced to the closing position in a reliable manner. In this case, too, the operability of the lever67is improved for the user, and the user can have an excellent operation feeling.

It is noted that when a conventional drive transmission mechanism that does not include the spring77intervenes between the lever67and the opening/closing mechanism53, there may occur a problem that the opening/closing mechanism53is not displaced to the opening position or the closing position due to the transmission loss of the drive transmission mechanism. Here, when the opening/closing mechanism53is not disposed at the opening position correctly, the toner discharge outlet52is not opened completely, and discharging of toner is not performed smoothly. In addition, when the opening/closing mechanism53is not disposed at the closing position correctly, when the toner container50is removed from the apparatus main body28, toner leaks out from the gap of the toner discharge outlet52, and the toner smears the peripheral of the attachment portion of the toner container50. However, according to the present embodiment, with the presence of the drive transmission mechanism76having the above-described configuration, the cylinder61of the opening/closing mechanism53is correctly displaced to the opening position or the closing position, and the toner discharge outlet52is opened and closed completely.

In the present embodiment, as described above, a coil spring is used as the spring77. However, this is a mere example, and any biasing member is applicable as far as it can exert the function of the spring77.

In the above-described embodiment, the first gear portion74A and the second gear portion75A are set such that the rotation angle of the first rotation portion74is the same as the rotation angle of the second rotation portion75. However, the present disclosure is not limited to this configuration. For example, the first gear portion74A and the second gear portion75A may be set such that the rotation angle of the second rotation portion75is larger than the rotation angle of the first rotation portion74. Specifically, the first gear portion74A and the second gear portion75A may be set such that when the lever67, together with the first rotation portion74, is rotated 45 degrees from the first operation position, the second rotation portion75is rotated 90 degrees. In this case, the spring77is maximally stretched before the lever67that is pivoted from the first operation position reaches the intermediate position, and thereafter, the spring77applies a biasing force in the compression direction. That is, with this configuration, the spring77is maximally stretched when the lever67is disposed at a position that is located between the first operation position and the intermediate position in the operation range of the lever67. In this case, the user can displace the toner discharge outlet52from the closing position to the opening position by slightly pivoting the lever67after the attachment of the toner container50.

In addition, the first gear portion74A and the second gear portion75A may be set such that the rotation angle of the second rotation portion75is smaller than the rotation angle of the first rotation portion74. Specifically, the first gear portion74A and the second gear portion75A may be set such that when the lever67, together with the first rotation portion74, is rotated by 90 degrees from the first operation position, the second rotation portion75is rotated 45 degrees. In this case, the spring77is maximally stretched after the lever67that is pivoted from the first operation position passes the intermediate position and is further pivoted to some extent, and thereafter, the spring77applies a biasing force in the compression direction. That is, with this configuration, the spring77is maximally stretched when the lever67is disposed at a position that is located between the intermediate position and the second operation position in the operation range of the lever67. In this case, the user can displace the toner discharge outlet52from the opening position to the closing position by slightly pivoting the lever67in the state where the toner discharge outlet52is opened after the attachment of the toner container50.

In the above-described embodiment, a configuration where the operation portion54is provided on the toner container50is described as an example. However, the present disclosure is applicable to a configuration where the operation portion54is provided in the apparatus main body28side.

In addition, in the above-described embodiment, a configuration where the image forming apparatus10includes four toner containers50is described as an example. However, the present disclosure is applicable to a configuration where the image forming apparatus10includes one toner container50.