Patent Description:
Conventionally, a constitution in which a toner cartridge in which toner is accommodated is detachably mountable to an apparatus main assembly of an image forming apparatus has been known. As such a toner cartridge, a constitution in which a toner supply unit accommodating toner for being supplied to an image forming portion in the apparatus main assembly and a residual toner accommodating unit accommodating residual toner collected from the image forming portion are provided has been proposed (<CIT> and <CIT>).

According to an aspect of the present invention, there is provided a toner cartridge comprising: a toner accommodating unit including a first accommodating portion and a second accommodating portion and configured to accommodate toner, wherein the toner accommodating unit includes a first end portion and a second end portion on a side opposite from the first end portion with respect to a first direction and includes a third end portion and a fourth end portion on a side opposite from the third end portion with respect to a second direction crossing the first direction, wherein the first accommodating portion is on a side closer to the first end portion than to the second end portion in the first direction and the second accommodating portion is on a side closer to the second end portion than to the first end portion in the first direction, wherein the first accommodating portion is provided with a discharge opening for permitting discharge of the toner, accommodated in the first accommodating portion, to an outside of the toner cartridge, the discharge opening being in a position closer to the third end portion than to the fourth end portion in the second direction, and wherein the second accommodating portion is provided with a receiving opening for receiving the toner from the outside of the toner cartridge to the second accommodating portion, the receiving opening being positioned closer to the third end potion than to the fourth end portion in the second direction; and a light transmitting portion having an incident surface and an emergent surface, wherein the incident surface is configured so that light is capable of being incident from the outside of the toner cartridge into an inside of the second accommodating portion, wherein the emergent surface is configured so that the light incident into the inside of the second accommodating portion through the incident surface is capable of emerging to the outside of the toner cartridge, and wherein the incident surface and the emergent surface are provided in positions closer to the fourth end portion than to the third end portion in the second direction and are exposed to the outside of the cartridge.

An embodiment will be described using <FIG> to part (c) of <FIG>. First, a schematic structure of an image forming apparatus of this embodiment will be described using <FIG>.

An image forming apparatus <NUM> is a laser beam printer of an electrophotographic type. As shown in <FIG>, the image forming apparatus <NUM> includes an apparatus main assembly (printer main body) A, a process cartridge B as an image forming portion, and a toner cartridge C. The apparatus main assembly A includes a laser scanner <NUM>, a sheet conveying portion <NUM>, a surface feeding portion <NUM>, a transfer roller <NUM>, a fixing portion <NUM>, a sheet discharging portion <NUM>, a reverse cleaning portion <NUM>, and the like. Further, although described specifically later, in the apparatus main assembly A, the process cartridge Band the toner cartridge C are disposed detachably mountable to the apparatus main assembly A. For this purpose, the apparatus main assembly A is provided with an openable door <NUM>.

The process cartridge B includes a photosensitive drum <NUM> as an image bearing member and a photosensitive member, a charging roller <NUM> as a charging member, a developing unit <NUM>, and a cleaning blade <NUM> as a cleaning member. Above the process cartridge B, the laser scanner <NUM> as an exposure device is provided.

The charging roller <NUM> is disposed in contact with an outer peripheral surface of the photosensitive drum <NUM> and electrically charges the photosensitive drum <NUM> under application of a voltage from the apparatus main assembly A. Further, the charging roller <NUM> is rotated by rotation of the photosensitive drum <NUM>. The developing unit <NUM> includes a developing roller <NUM> as a developer carrying member for carrying and conveying toner as a developer. The developing roller <NUM> is provided opposed to the photosensitive drum <NUM>.

The cleaning blade <NUM> is an elastic member disposed in contact with the outer peripheral surface of the photosensitive drum <NUM>, and cleans the surface of the photosensitive drum <NUM>. The cleaning blade <NUM> elastically contacts the photosensitive drum <NUM> at a free end thereof, and thus removes, from the photosensitive drum <NUM>, toner remaining after a sheet S described later passes through between the photosensitive drum <NUM> and the transfer roller <NUM>.

The sheet feeding portion <NUM> includes a cassette 103a, a pick-up roller 103b for feeding an uppermost sheet accommodated in the cassette 103a, and a separation roller 103c and a separation pad 103d which are used for separating the sheet S one by one fed by the pick-up roller 103b. The sheet conveying portion <NUM> includes a conveying roller pair 102a and a registration roller pair 102b which are used for conveying the sheet S fed from the sheet feeding portion <NUM>. The registration roller pair 102b conveys the sheet S to a transfer portion between the photosensitive drum <NUM> and the transfer roller <NUM> in synchronism with a timing of a toner image formed on the photosensitive drum <NUM>.

The fixing portion <NUM> includes a fixing roller 105a heated by a heating source such as a heater and a pressing roller 105b forming a fixing nip in which the sheet S is nipped between the fixing roller 105a and the pressing roller 105b. The sheet S on which the toner image is transferred in the transfer portion is conveyed to the fixing portion <NUM> and is heated and pressed in the fixing nip. By this, the toner image is fixed on the sheet S.

The sheet discharging portion <NUM> includes a discharging roller pair 110a and discharges the sheet S, on which the toner image is fixed, onto a discharge tray <NUM> by the discharging roller pair 110a. The reverse conveying portion <NUM> includes a reverse conveying roller pair 111a and reverses front and back sides (surfaces) of the sheet S passed through the fixing portion <NUM> in the case where images are formed on the both sides of the sheet S, and then conveys the sheet S toward the registration roller pair 102b.

Next, an operation of the image forming apparatus <NUM> will be described using <FIG>. The photosensitive drum <NUM> rotationally driven by an unshown driving source (motor) is electrically charged uniformly to a predetermined potential. The surface of the photosensitive drum <NUM> after the charging is exposed to light on the basis of image information by the laser scanner <NUM>, and an electric charge in an exposure portion is removed, so that an electrostatic latent image is formed. To the electrostatic latent image on the photosensitive drum <NUM>, the toner is supplied from the developing roller <NUM>, so that the electrostatic latent image is visualized as the toner image.

On the other hand, in parallel to such a toner image forming operation, the sheet S is fed from the sheet feeding portion <NUM>. The sheet S fed from the sheet feeding portion <NUM> is conveyed to the transfer portion by the registration roller pair 102b while being timed to formation of the toner image on the photosensitive drum <NUM>. When the sheet S passed through the transfer portion, a voltage is applied from the apparatus main assembly A to the transfer roller <NUM>, so that the toner image on the photosensitive drum <NUM> is transferred as an unfixed image onto the sheet S. Thereafter, the sheet S on which the toner image is fixed is conveyed to the transfer portion <NUM>, so that the unfixed image is heated and pressed, and thus is fixed on the surface of the sheet S. The sheet S on which the toner image is fixed is discharged and stacked on the discharge tray <NUM> by the sheet discharging portion <NUM>. Incidentally, in the case where the images are formed on the both sides of the sheet S, the sheet S is conveyed to the reverse conveying portion <NUM>, and the toner image is formed on the back side of the sheet S similarly as described above.

The process cartridge B will be described using <FIG>. As shown in <FIG>, the process cartridge B is constituted by a cleaning unit <NUM> provided with the cleaning blade <NUM> and the like and a developing unit <NUM> provided with the developing roller <NUM>. The cleaning unit <NUM> includes the photosensitive drum <NUM>, the cleaning blade <NUM>, the charging roller <NUM>, a charging roller cleaner <NUM> as a cleaning member for the charging roller <NUM>, a residual toner primary accommodating portion 10a, a first residual toner feeding passage 10b, and a second residual toner feeding passage 10c. Toner (residual toner) removed from the photosensitive drum by the cleaning blade <NUM> is conveyed from the residual toner primary accommodating portion 10a to the toner cartridge C through the first residual toner feeding passage 10b and the second residual toner feeding passage 10c.

As shown in <FIG>, the developing unit <NUM> includes the developing roller <NUM>, a supplying roller <NUM>, a developing blade <NUM>, a developing chamber <NUM> in which the developing roller <NUM> is disposed, a developer accommodating chamber <NUM> from which the toner is supplied to the developing chamber <NUM>, and a toner receiving chamber <NUM> for receiving the toner supplied from the toner cartridge C. The developing roller <NUM> supplies the toner to a developing region.

Then, the developing roller <NUM> develops the electrostatic latent image, with the toner, formed on the photosensitive drum <NUM>. The supplying roller <NUM> supplies the toner in the developing chamber <NUM> to the developing roller <NUM>. Such a supplying roller <NUM> is disposed so that a rotational axis direction thereof is parallel to a rotational axis direction of the developing roller <NUM>, an on an outer peripheral surface thereof, an elastic layer such as a sponge or the like is formed so that the developer is easily conveyed. The developing blade <NUM> contacts a peripheral surface of the developing roller <NUM> and defines an amount of the toner deposited on the peripheral surface of the developing roller <NUM>. Further, the developing blade <NUM> imparts a triboelectric charge to the toner.

The toner accommodated in the developer accommodating chamber <NUM> is sent to the developing chamber <NUM> by rotation of a stirring member <NUM> and then is supplied to the developing roller <NUM>. A remaining amount of the toner in the developer accommodating chamber <NUM> is detected by an unshown remaining amount detecting portion. Then, when the amount of the toner in the developer accommodating chamber <NUM> becomes a certain amount or less, the toner is supplied to the process cartridge B by the toner cartridge C. Supply of the toner from the toner cartridge C to the developing unit <NUM> of the process cartridge B is made through a supply opening 21c of a stay <NUM>, the toner receiving chamber <NUM>, and a delivery opening 21d, so that the toner is accommodated in the developer accommodating chamber <NUM>.

Next, the constitution of the process cartridge B will be described more specifically using <FIG>, parts (a) and (b) of <FIG>, and parts (a) and (b) of <FIG>. As described above, the cleaning unit <NUM> includes the photosensitive drum <NUM>, the charging roller <NUM>, and the cleaning blade <NUM>. Similarly, the developing unit <NUM> includes the developing roller <NUM>, the developing blade <NUM>, the developing chamber <NUM>, the developer accommodating chamber <NUM>, and the toner receiving chamber <NUM>.

As shown in parts (a) and (b) of <FIG>, the cleaning unit <NUM> is constituted by a cleaning frame <NUM>, the stay <NUM>, and a side cover <NUM>. The cleaning frame <NUM> supports the cleaning blade <NUM>, the charging roller <NUM>, and the charging roller cleaner <NUM>. As shown in part (b) of <FIG>, the photosensitive drum <NUM> is rotatably supported by a drum pin <NUM> mounted in the cleaning frame <NUM> on one side and by a photosensitive drum supporting portion 7b provided on the side cover <NUM> on the other side (opposite side).

Further, as shown in parts (a) and (b) of <FIG>, at an end portion of the developing roller <NUM> with respect to an axial direction, bearing members <NUM> and <NUM> are disposed, and the developing unit <NUM> is connected to the cleaning unit <NUM> so as to be rotatable about a swing axis defined by a rectilinear line including supporting axes 8a and 8b. The swing axis <NUM> is disposed substantially parallel to a rotational axis 11b of the photosensitive drum <NUM>.

A constitution in which the developing unit <NUM> is supported by the cleaning unit <NUM> will be specifically described. As shown in part (a) of <FIG>, a cylindrical shape portion 5a provided on the bearing member <NUM> is supported by a cylindrical hole portion 7a provided in the side cover <NUM>. The supporting axis 8b is defined by a common axis to the cylindrical hole portion 7a of the side cover <NUM> and the cylindrical shape portion 5a of the bearing member <NUM>. Further, at a rotation center of the cylindrical shape portion 5a of the bearing member <NUM>, a developing coupling <NUM> as a drive input member for receiving drive from the apparatus main assembly A is provided.

Further, as shown in part (b) of <FIG>, a pin <NUM> is inserted so as to extend over a cylindrical hole portion 20a of the cleaning frame <NUM> of the cleaning unit <NUM> and the cylindrical hole portion 4a of the bearing member <NUM>.

The supporting axis 8b is defined by a common axis to the pin <NUM> and the cylindrical hole portion 4a of the bearing member <NUM>. The supporting axes 8a and 8b are disposed coaxially with each other, and as described above, the swing axis <NUM> is defined by a rectilinear line including the supporting axes 8a and 8b.

As described above, the developing unit <NUM> is supported rotatably about the swing axis <NUM> relative to the cleaning unit <NUM>. Further, the developing unit <NUM> is urged toward the photosensitive drum <NUM> of the cleaning unit <NUM> by pressing springs 19a and 19b which are elastic members, so that the developing roller <NUM> is contacted to the photosensitive drum <NUM>.

Next, a contact and separation operation of the developing unit <NUM> relative to the cleaning unit <NUM> will be described using parts (a) and (b) of <FIG>. Incidentally, parts (a) and (b) of <FIG> are illustrations in which the side cover <NUM> is omitted for illustrating a separation mechanism <NUM> of the apparatus main assembly A. As shown in part (a) of <FIG>, a projected portion 5b is provided in a position where the bearing member <NUM> opposes the separation mechanism <NUM>. In this embodiment, in a state in which the process cartridge B is mounted in the apparatus main assembly 100A, the separation mechanism <NUM> is provided below the developing unit <NUM>. Further, the projected portion 5b is provided at a lower end portion of the bearing member <NUM>. The separation mechanism <NUM> is provided in the apparatus main assembly 100A and is swingable substantially in up-down direction about a swing axis 100a as a center by a driving source such as an unshown motor.

As shown in part (a) of <FIG>, in a position where the projected portion 5b does not contact the separation mechanism <NUM>, the developing roller <NUM> is contacted to the photosensitive drum <NUM> by an urging force of the pressing springs 19a and 19b.

This position is an image forming position where the electrostatic latent image formed on the surface of the photosensitive drum <NUM> is capable of being developed by the developing roller <NUM>.

As shown in part (b) of <FIG>, the separation mechanism <NUM> provided in the apparatus main assembly A swings about the swing axis 100a and contacts the projected portion 5b receives a force from the separation mechanism <NUM>, so that the developing unit <NUM> is rotated about the swing axis <NUM> and a rotation center in an arrow R2 direction. By this, the developing roller <NUM> is separated from the photosensitive drum <NUM> against the urging force of the pressing springs 19a and 19b. This position is a non-image forming position retracted from the image forming position.

When the separation mechanism <NUM> returns from the position of part (b) of <FIG> to the position of part (a) of <FIG> which is an original position, the separation mechanism <NUM> is separated from the projected portion 5b. Then, by the urging force of the pressing springs 19a and 19b, the developing roller <NUM> is contacted to the photosensitive drum <NUM> again. Thus, in this embodiment, the position of the developing unit <NUM> is capable of being switched between a contact position (image forming position) and a separated position (non-image forming position) by the separation mechanism <NUM>. That is, an attitude of the developing unit <NUM> in the process cartridge B is switchable between the contact position and the separated position relative to the photosensitive drum <NUM>. By this, it is possible to suppress toner deterioration and unnecessary toner consumption during non-image formation.

A residual toner feeding constitution inside the cleaning unit <NUM> will be described using <FIG>, <FIG>, and <FIG> is a schematic sectional view of the cleaning unit <NUM> when the cleaning unit <NUM> is viewed from a top surface side. As shown in <FIG>, <FIG>, and <FIG>, the first residual toner feeding passage 10b disposed in a direction parallel to the drum axis is provided with a first residual toner feeding member <NUM>, and the second residual toner feeding passage 10c disposed in a direction perpendicular to the drum axis is provided with a second residual toner feeding member <NUM>. Further, the second residual toner feeding passage 10c and the second residual toner feeding member <NUM> are disposed inside an end portion of the cleaning blade <NUM> with respect to the drum axis direction (longitudinal direction).

As described above, the residual toner on the photosensitive drum <NUM> is collected in the residual toner primary accommodating portion 10a by the cleaning blade <NUM>. When the residual toner primary accommodating portion 10a is filled with the residual toner, the remaining residual toner reaches the first residual toner feeding passage 10b. The residual toner reached the first residual toner feeding passage 10b is fed in the drum axis direction by a helical portion 70a provided in the first residual toner feeding member <NUM>. Then, the residual toner fed by the first residual toner feeding member <NUM> reaches the second residual toner feeding passage 10c. The residual toner reached the second residual toner feeding passage 10c is fed above the cleaning blade <NUM> and in a direction perpendicular to the drum axis by a helical portion 71a (third residual toner feeding member) of the second residual toner feeding member <NUM>. Further, the residual toner fed to an end portion of the second residual toner feeding member <NUM> is discharged from a residual toner discharge opening <NUM> into the residual toner accommodating portion <NUM> of the toner cartridge C described below through a residual toner receiving opening <NUM> (see <FIG> and the like).

Next, the toner cartridge C will be described using <FIG> and <FIG> to <NUM>. As shown in <FIG>, the toner cartridge includes a toner accommodating unit <NUM> constituted so as to include a first end portion (left-side end portion of <FIG>) and a second end portion (right-side end portion of <FIG>) on a side opposite from the first end portion with respect to an axial direction E (first direction) and includes a third end portion (left-side end portion of <FIG>, <FIG> and <FIG>) and a fourth end portion (right-side end portion of <FIG>, <FIG>, and <FIG>) on a side opposite from the third end portion with respect to a horizontal direction H crossing the axial direction E and so as to accommodate the toner.

The horizontal direction H is a horizontal direction in the case where the toner cartridge C is viewed in the axial direction E in a state in which the toner cartridge C is mounted in the apparatus main assembly A, and is a direction perpendicular to the axial direction E in this embodiment. In other words, the horizontal direction H is a horizontal direction in the case where the toner cartridge C is directed to a direction when the toner cartridge C is mounted in the apparatus main assembly A. Further, in the following description, the first, second, third, and fourth end portions are also referred to as a left end portion <NUM>, a right end portion <NUM>, a front end portion <NUM>, and a rear end portion <NUM>, respectively.

The toner accommodating unit <NUM> includes a toner supplying unit <NUM> and a residual toner accommodating unit <NUM>. The toner cartridge C is detachably mountable together with the process cartridge B to the apparatus main assembly A and is also detachably mountable to the process cartridge B.

The toner supplying unit <NUM> is extended in the axial direction E which is the longitudinal direction of the toner cartridge C and is capable of supplying the toner to the process cartridge B. The residual toner accommodating unit <NUM> is disposed on the right end portion <NUM> (second end portion) side of the toner supplying unit <NUM> with respect to the axial direction E and is capable of accommodating the residual toner collected by the process cartridge B.

The toner supplying unit <NUM> includes, as shown in <FIG>, a toner accommodating container <NUM> as a first accommodating portion and a toner discharge opening 31a which is provided outside the toner cartridge C and which is used as a discharge opening for permitting discharge of the toner from the toner accommodating container <NUM>. The toner accommodating container <NUM> is formed by a supplying member frame 32a including the toner accommodating portion 30a and by a supplying portion cover 32b. Further, the supplying member frame 32a is provided with the toner discharge opening 31a through which the toner is discharged from the toner accommodating portion 30a. Further, a shutter member <NUM> capable of opening and closing the toner discharge opening 31a is provided. The shutter member <NUM> is rotated in an arrow R1 direction in interrelation with a mounting and demounting operation of the toner cartridge C relative to the process cartridge B, so that the shutter member <NUM> opens and closes the toner discharge opening 31a. The shutter member <NUM> is disposed outside the supplying member frame 32a. Further, as shown in <FIG> and <FIG>, the toner accommodating container <NUM> is provided with a cover 33a as a sealing member for sealing a filling opening <NUM> for permitting filling of the toner accommodating container <NUM> with the toner.

As shown in <FIG>, the toner accommodating portion 30a includes, as a toner feeding member for feeding the toner to the toner discharge opening 31a (<FIG>), a toner accommodating portion screw member <NUM> for feeding the toner toward the toner discharge opening 31a. Further, the toner accommodating portion 30a includes a toner accommodating portion stirring and feeding unit <NUM> for feeding the toner toward the toner accommodating portion screw member <NUM> while stirring the toner. The toner accommodating portion stirring and feeding unit <NUM> is rotatable about a rotational axis extending in the axial direction E and stirs the toner in the toner accommodating container <NUM>.

Further, as shown in parts (a) and (b) of <FIG>, the toner fed to the toner discharge opening 31a is discharged to an outside through the toner discharge opening 31a by a volume fluctuation of a pump 37a provided in a pump unit <NUM>. The pump unit <NUM> is provided on the left end portion <NUM> side (first end portion side) of the toner accommodating container <NUM> with respect to the axial direction E and is constituted by the pump 37a changing in volume by expansion and contraction, a cam 37b expanded and contracted by rotation of the pump 37a, and a link arm 37c. Further, as shown in <FIG>, the toner supplying unit <NUM> includes a stirring drive input portion <NUM> which is provided at one end thereof with respect to the axial direction E (longitudinal direction of <FIG> and <FIG>) and which is, as a toner feeding and driving portion for driving the toner feeding portion, for driving the toner accommodating portion stirring and feeding unit <NUM>, and includes a pump/screw drive input portion <NUM> as a driving force receiving member for receiving, from an outside of the toner cartridge C, a driving force for driving the pump unit <NUM> and the toner accommodating portion screw member <NUM>. The pump/screw drive input portion <NUM> is provided on a side surface of the toner cartridge C on the left end portion <NUM> side, and a rotational driving force is inputted from the apparatus main assembly A to a pump/screw coupling 39a which is a projected-shape portion. This rotational driving force is converted into reciprocating motion by the cam 37b and the link arm 37c. Then, by using this reciprocating motion, a bellow-shaped portion of the pump 37a is expanded and contracted, so that a volume fluctuation is made.

As shown in <FIG> and parts (a) and (b) of <FIG>, the residual toner accommodating unit <NUM> includes a residual toner receiving opening <NUM> as a receiving opening for receiving the toner from the outside of the toner cartridge C, for receiving the residual toner from the process cartridge B in this embodiment, a residual toner accommodating container <NUM> as a second accommodating portion in which the residual toner received through the residual toner receiving opening <NUM> is accommodated, and a light transmitting portion <NUM> through which detection light for detecting an amount of the residual toner accommodated in the residual toner accommodating container <NUM>.

The residual toner accommodating container <NUM> is formed by a residual toner accommodating portion frame 41a as a frame including the residual toner accommodating portion 40a and by a residual toner accommodating cover 41b. The residual toner accommodating cover 41b is provided with a residual toner receiving opening <NUM> for receiving the residual toner collected from the process cartridge B. The residual toner accommodating cover 41b includes a residual toner shutter member <NUM> for opening and closing the residual toner receiving opening <NUM>. The residual toner shutter member <NUM> is opened and closed in an arrow R3 direction of <FIG> in interrelation with the mounting and demounting of the toner cartridge C relative to the apparatus main assembly A.

Further, as shown in parts (a) and (b) of <FIG> and <FIG>, the residual toner accommodating unit <NUM> is provided with the above-described light transmitting portion <NUM>. The light transmitting portion <NUM> is disposed between the residual toner accommodating portion 40a and a non-driving-side toner cartridge side cover <NUM>. That is, with respect to the axial direction E, the light transmitting portion <NUM> is disposed at an end portion (second end portion) of the toner cartridge C on a side opposite from the toner discharge opening 31a provided in the above-described toner supplying unit <NUM>. Incidentally, the light transmitting portion <NUM> is put in a state in which a portion other than a light-emitting-side incident surface 1102a and a light-receiving-side emergent surface 1103a which are described later is covered with the non-driving-side toner cartridge side cover <NUM> mounted on a side surface of the residual toner accommodating portion frame 41a on a right end side (see <FIG>). The non-driving-side toner cartridge side cover <NUM> is provided with openings <NUM> and <NUM> through which the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a are exposed to the outside, respectively.

Here, the light transmitting portion <NUM> will be specifically described using parts (a) and (b) of <FIG>. Part (a) of <FIG> is a perspective view of the residual toner accommodating unit <NUM> viewed from the non-driving side. Part (b) of <FIG> is a perspective view of the residual toner accommodating unit <NUM> viewed from the driving side. Incidentally, in parts (a) and (b) of <FIG>, for explanation, members other than the residual toner accommodating portion frame 41a and the light transmitting portion <NUM> are not shown.

As shown in part (a) of <FIG>, the light transmitting portion <NUM> includes a light-emitting-side light transmitting member <NUM> as a first light transmitting member and a light-receiving-side light transmitting member <NUM> as a second light transmitting member. The light-emitting-side light transmitting member <NUM> causes light irradiated from a light emitting element (not shown) such as an LED provided outside the residual toner accommodating unit <NUM> to emit light inside the residual toner accommodating container <NUM>. The light-receiving-side light transmitting member <NUM> receives the light emitted through the light-emitting-side light transmitting member <NUM> emerges the light toward a light receiving element (not shown) such as a photo-transistor provided outside the residual toner accommodating unit <NUM>. Incidentally, as shown in <FIG>, with respect to the horizontal direction H, at a portion of the residual toner accommodating portion frame 41a closer to the front end portion <NUM> (third end portion) than to the rear end portion <NUM> (fourth end portion), a first opening <NUM> and a second opening <NUM> which communicate with an inside of the residual toner accommodating container <NUM> are provided. In this embodiment, the first opening <NUM> and the second opening <NUM> are arranged in the horizontal direction H.

The light-emitting-side light transmitting member <NUM> includes the light-emitting-side incident surface 1102a as an incident surface and a light-emitting-side emergent surface 1102b. The light-emitting-side incident surface 1102a is such that the light irradiated from the light emitting element provided outside the residual toner accommodating container <NUM> (hereinafter, this light is referred to as detection light <NUM>) is capable of incident on the light-emitting-side incident surface 1102a. The light-emitting-side light transmitting member <NUM> guides the detection light <NUM> incident from the light-emitting-side incident surface 1102a to the inside of the residual toner accommodating container <NUM>. The light-emitting-side emergent surface 1102b is provided inside the residual toner accommodating container <NUM> and is capable of emerging the detection light <NUM> guided by the light-emitting-side light transmitting member <NUM>.

The light-emitting-side light transmitting member <NUM> is provided so as to extend to the first opening <NUM> in a direction from the rear end portion <NUM> to the front end portion <NUM> of the toner cartridge C. Further, a part of the light-emitting-side light transmitting member <NUM> enters the inside of the residual toner accommodating container <NUM> through the first opening <NUM>, and the light-emitting-side emergent surface 1102b is provided inside the residual toner accommodating container <NUM>. Accordingly, the detection light <NUM> incident from the light-emitting-side incident surface 1102a provided outside the residual toner accommodating container <NUM> passes through the light-emitting-side light transmitting member <NUM> and emerges from the light-emitting-side emergent surface 1102b on the inside of the residual toner accommodating container <NUM>.

The light-receiving-side light transmitting member <NUM> includes the light-receiving-side incident surface 1103b and a light-receiving-side emergent surface 1103a. The light-receiving-side incident surface 1103b is such that the detection light <NUM> emerged from the light-emitting-side emergent surface 1102b provided inside the residual toner accommodating container <NUM> is capable of incident on the light-receiving-side incident surface 1103b. The light-receiving-side incident surface 1103b is disposed so as to oppose the light-emitting-side emergent surface 1102b with a predetermined gap. The light-receiving-side light transmitting member <NUM> guides the detection light <NUM> incident from the light-receiving-side incident surface 1103b to the outside of the residual toner accommodating container <NUM>. The light-receiving-side emergent surface 1103b is provided outside the residual toner accommodating container <NUM> and is capable of emerging the detection light <NUM>, guided by the light-receiving-side light transmitting member <NUM>, toward the light emitting element.

The light-receiving-side light transmitting member <NUM> is provided so as to extend to the second opening <NUM> in a direction from the rear end portion <NUM> to the front end portion <NUM> of the toner cartridge C. Further, a part of the light-receiving-side light transmitting member <NUM> enters the inside of the residual toner accommodating container <NUM> through the second opening <NUM>, and the light-receiving-side incident surface 1103b is provided inside the residual toner accommodating container <NUM>. Accordingly, the detection light <NUM> emerged from the light-receiving-side incident surface 1103b inside the residual toner accommodating container <NUM> passes through the predetermined gap and incident on the light-receiving-side incident surface 1103b. Then, the detection light <NUM> incident on the light-receiving-side incident surface 1103b passes through the light-receiving-side light transmitting member <NUM> and is emerged from the light-receiving-side emergent surface 1103a provided outside the residual toner accommodating container <NUM>.

As shown in part (b) of <FIG>, the light-emitting-side emergent surface 1102b and the light-receiving-side incident surface 1103b are disposed in positions opposing each other, and an optical path <NUM> along which the detection light <NUM> passes through therebetween is formed. By a length of a time in which this optical path <NUM> is blocked by the toner, a full state of the toner (amount) in the residual toner accommodating portion 40a is detected. However, in the case where the optical path is formed in consideration of light refraction generating during light irradiation from the light-emitting-side emergent surface 1102b and during light incidence on the light-receiving-side incident surface 1103b, the constitution is not limited to a constitution in which the light-emitting-side emergent surface 1102b and the light-receiving-side incident surface 1103b are disposed opposed to each other.

<FIG> is a perspective view showing a schematic constitution of the residual toner accommodating unit <NUM>. Incidentally, for explanation, the residual toner accommodating cover 41b is not shown. <FIG> is a sectional view showing the schematic constitution of the residual toner accommodating unit <NUM>. For explanation, the light transmitting portion <NUM> is shown in a transmissive state.

As shown in <FIG>, in the residual toner accommodating unit <NUM>, a partition member <NUM> and a first residual toner accommodating screw <NUM> and a second residual toner feeding screw <NUM> which are as a residual toner feeding member for feeding the residual toner in the residual toner accommodating portion 40a. The partition member <NUM> partitions the residual toner accommodating portion 40a in the residual toner accommodating unit <NUM> into three portions consisting of a first residual toner accommodating portion 40a1, a second residual toner accommodating portion 40a2, and a third accommodating portion 40a3.

The first residual toner accommodating screw <NUM> is disposed as to extend between the inside of the first residual toner accommodating portion 40a1 and the second residual toner accommodating portion 40a2 and feeds the residual toner, accommodated in the first residual toner accommodating portion 40a1, in an axis 44a direction substantially parallel to the rotational axis 11b of the photosensitive drum <NUM>. The second residual toner accommodating screw <NUM> receives drive from the first residual toner accommodating screw <NUM> and feeds the residual toner, fed by the first residual toner accommodating screw <NUM>, in an axis 45a direction which is an obliquely upward direction (see <FIG>). By this, the residual toner is fed from the second residual toner accommodating portion 40a2 toward the third residual toner accommodating portion 40a3.

As shown in <FIG>, when an amount of the residual toner accommodated in the third residual toner accommodating portion 40a3 exceeds a certain amount, the residual toner drops into the first residual toner accommodating portion 40a1 through a gap <NUM> provided between the residual toner accommodating cover 41b and the partition member <NUM>. The dropped residual toner is fed again toward the third residual toner accommodating portion 40a3 similarly as in the case of the residual toner received through the residual toner receiving opening <NUM>. This flow of the residual toner is repeated, and when the third residual toner accommodating portion 40a3 becomes a full state, the residual toner overflowing from the inside of the third residual toner accommodating portion 40a3 starts to accumulate inside the first residual toner accommodating portion 40a1. Then, when the amount of the residual toner in the first residual toner accommodating portion 40a1 exceeds a certain amount, the residual toner blocks the above-described optical path <NUM> (see part 8b) of <FIG>). By this, it is possible to detect that the toner in the residual toner accommodating portion 40a is in a full state.

Thus, the light-emitting-side emergent surface 1102b and the light-receiving-side incident surface 1103b are disposed inside the first residual toner accommodating portion 40a1. Further, the residual toner receiving opening <NUM> is provided in a position overlapping with the first residual toner accommodating portion 40a1, and the residual toner received through the residual toner receiving opening <NUM> is accommodated in the first residual toner accommodating portion 40a1. That is, in this embodiment, the light-emitting-side emergent surface 1102b and the light-receiving-side incident surface 1103b are disposed in the neighborhood of the residual toner receiving opening <NUM>. Further, the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a are disposed in positions overlapping with the third residual toner accommodating portion 40a3 as viewed in the axial direction E.

Then, a mounting and demounting method of the process cartridge B and the toner cartridge C into the apparatus main assembly A will be described using parts (a) and (b) of <FIG> and parts (a) to (c) of <FIG>. As shown in part (a) of <FIG>, an inside space of the apparatus main assembly A is a mounting portion for the process cartridge B and the toner cartridge C. The openable door <NUM> is provided so as to be rotatable in an arrow R5 direction about a rotational axis 107a relative to the apparatus main assembly A (see parts (a) to (c) of <FIG>). Part (a) of <FIG> is a schematic view showing a state in which the openable door <NUM> is open.

Further, the apparatus main assembly A includes guiding portions <NUM> and <NUM>. The guiding portions <NUM> and <NUM> are provided along an axial direction D, which is a mounting direction of the process cartridge B and the toner cartridge C, on opposite sides, respectively, with respect to the axial direction E of the process cartridge B and the toner cartridge C in a mounted state. The process cartridge B is, as shown in <FIG>, provided with upper bosses <NUM> and <NUM> and lower bosses <NUM> and <NUM> on opposite sides, respectively, with respect to the axial direction E.

The mounting of the process cartridge B and the toner cartridge C into the apparatus main assembly A is performed from the process cartridge B. First, when the process cartridge B is mounted into the apparatus main assembly A, as shown in part (a) of <FIG> and part (a) of <FIG>, the process cartridge B is mounted into the apparatus main assembly A along the axial direction D so that the guiding portion <NUM> is sandwiched between the upper boss <NUM> and the lower boss <NUM> and so that the guiding portion <NUM> is sandwiched between the upper boss <NUM> and the lower boss <NUM>. The axial direction D which is the mounting direction is a direction perpendicular to the above-described axial direction E (longitudinal direction). Thus, the process cartridge B is inserted while sandwiching the guiding portions <NUM> and <NUM> by the upper bosses <NUM> and <NUM> and the lower bosses <NUM> and <NUM>, so that the process cartridge B is guided to the mounting portion inside the apparatus main assembly A by the guiding portions <NUM> and <NUM>.

The toner cartridge C is provided with positioning bosses 50a and 60a on a front side (upstream side) with respect to the mounting direction and on opposite sides with respect to the axial direction E. Further, the toner cartridge C is provided with portions-to-be-guided 50b and 60b on a rear side (downstream side) with respect to the mounting direction than the positioning bosses 50a and 60a are and on opposite sides with respect to the axial direction E. The positioning boss 50a and the portion-to-be-guided 50b are provided on an outside end surface of a driving-side toner cartridge side cover <NUM> with respect to the axial direction E. The positioning boss 60a and the portion-to-be-guided 60b are provided on an outside end surface of a non-driving-side toner cartridge side cover <NUM> with respect to the axial direction E. The process cartridge B is provided with toner cartridge positioning portions 21a and 21b on the stay <NUM> as shown in parts (a) and (b) of <FIG>.

As shown in part (b) of <FIG> and part (b) of <FIG>, when the toner cartridge C is mounted into the apparatus main assembly A, the portions-to-be-guided 50b and 60b are placed on the guiding portions <NUM> and <NUM>, respectively, and are mounted in the axial direction D. As shown in part (c) of <FIG>, when the toner cartridge C is mounted to a mounting completion position, the positioning bosses 50a and 60a of the toner cartridge C enter the positioning portions 21a and 21b, respectively, of the process cartridge B. At this time, leading end sides of the portions-to-be-guided 50b and 60b with respect to the mounting direction are separated from the guiding portions <NUM> and <NUM>, and trailing ends thereof are in a contact state with the guiding portions <NUM> and <NUM>. By this, the toner cartridge C is positioned to the process cartridge B. Further, the trailing ends of the portions-to-be-guided 50b and 60b contact the guiding portions <NUM> and <NUM>, so that a position of the toner cartridge C in the apparatus main assembly A is determined.

When the openable door <NUM> is closed after the process cartridge B and the toner cartridge C are mounted, the image forming apparatus <NUM> is in a state in which the image is capable of being formed. When the toner cartridge C and the process cartridge B are demounted, a procedure reveres to the above-described procedure is performed.

The toner discharge opening 31a and the residual toner receiving opening <NUM> of the toner cartridge C are portion where the toner is delivered boss the toner cartridge C and the process cartridge B which is a separate frame. For example, when the process cartridge B and the toner cartridge C are mounted into the apparatus main assembly A, the toner discharge opening 31a is connected to the supply opening 21c (<FIG>) of the process cartridge B, and the residual toner receiving opening <NUM> is connected to the residual toner discharge opening <NUM> (<FIG>) of the process cartridge B. On the other hand, when the process cartridge B and the toner cartridge C are demounted from the apparatus main assembly A, the toner discharge opening 31a is separated from the supply opening 21c of the process cartridge B, and the residual toner receiving opening <NUM> is separated from the residual toner discharge opening <NUM> of the process cartridge B.

Thus, the toner cartridge C is capable of being mounted to and demounted from the process cartridge B, and therefore, for example, when the toner cartridge C is demounted from the process cartridge B, there is a liability that toner leakage from the toner discharge opening 31a or the residual toner receiving opening <NUM> occurs. On the other hand, the light-emitting-side incident surface 1102a of the light transmitting portion <NUM> is exposed to the outside of the toner cartridge C because the light is incident from an external light emitting element. Similarly, the light-receiving-side emergent surface 1103a emerges the light toward an external light receiving element, and therefore, is exposed to the outside of the toner cartridge C. Accordingly, as described above, there is a liability that the toner leaked through the toner discharge opening 31a or the residual toner receiving opening <NUM> is deposited on the light-emitting-side incident surface 1102a or the light-receiving-side emergent surface 1103a.

When a contaminant such as the toner is deposited on the light-emitting-side incident surface 1102a, the detection light <NUM> irradiated from the light emitting element cannot be sufficiently transmitted to the light-emitting-side emergent surface 1102b through the light-emitting-side light transmitting member <NUM>. Similarly, the light-receiving-side emergent surface 1103a cannot sufficiently emerge the detection light <NUM> toward the light receiving element when the contaminant such as the toner is deposited thereon. For this reason, when the toner or the like is deposited on the light-emitting-side incident surface 1102a or the light-receiving-side emergent surface 1103a, there is a liability that detection accuracy of the toner through the light transmitting portion <NUM> lowers. That is, the lowering in detection accuracy leads to a lowering in accuracy of full-state detection of the residual toner amount in the residual toner accommodating portion 40a.

For this reason, in this embodiment, as in the following, a positional relationship of the toner discharge opening 31a and the residual toner receiving opening <NUM> with the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a is defined.

First, as shown in <FIG> and <FIG> described above, the residual toner accommodating unit <NUM> is disposed on a side closer to the right end portion <NUM> than to the left end portion <NUM> of the toner cartridge C with respect to the axial direction E (longitudinal direction). Incidentally, in the following, the horizontal direction (second direction) which is perpendicular to the axial direction E (first direction) and which is viewed in the longitudinal direction in a state in which the toner cartridge C is mounted in the apparatus main assembly A is indicated by H. The horizontal direction H viewed in the longitudinal direction is perpendicular to the longitudinal direction and is inclined with respect to the axial direction D. However, directions of this horizontal direction H on one end side and the other end side are approximately the same directions as directions of the axial direction D on one end side and the other end side, respectively. Further, a direction crossing the axial direction E and the horizontal direction is a third direction. In this embodiment, the third direction is a vertical direction V perpendicular to the axial direction E and the horizontal direction H.

The toner discharge opening 31a is positioned on a side closer to the left end portion <NUM> than to the right end portion <NUM> of the toner cartridge C with respect to the axial direction E. That is, the toner discharge opening 31a is positioned near an end portion of the toner supplying unit <NUM> on a side opposite from the residual toner accommodating unit <NUM> with respect to the axial direction E. Further, the toner discharge opening 31a is positioned in a position closer to the front end portion <NUM> than to the near end portion <NUM> of the toner cartridge C with respect to the horizontal direction H perpendicular to the axial direction E. In this embodiment, the toner discharge opening 31a is positioned at an end portion of the toner cartridge C on a downstream side with respect to the mounting direction. The toner discharge opening 31a is open toward the axial direction E as shown by a center line 31b, and is open toward the right end side in this embodiment.

The residual toner receiving opening <NUM> is positioned in a position closer to the front end portion <NUM> than to the rear end portion <NUM> of the toner cartridge C with respect to the horizontal direction H perpendicular to the axial direction E. In this embodiment, the residual toner receiving opening <NUM> is positioned at an end portion on a downstream side with respect to the mounting direction. Further, the residual toner receiving opening <NUM> is positioned in a position closer to the right end portion <NUM> than to the left end portion <NUM> of the toner cartridge C with respect to the axial direction E. The residual toner receiving opening <NUM> is open in a direction crossing the axial direction E as shown by a center line 42a, and in this embodiment, opens in a direction perpendicular to each of the axial direction E and the axial direction D and opens upward.

The light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a are provided in positions closer to the right end portion <NUM> than to the left end portion <NUM> of the toner cartridge C with respect to the axial direction E and are exposed to the outside. That is, the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a are disposed near the end portion of the residual toner accommodating unit <NUM> on a side opposite from the toner supplying unit <NUM> with respect to the axial direction E. In this embodiment, the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a are provided on a side surface of the toner cartridge C on the right end portion <NUM> side with respect to the axial direction E. The light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a are, as described above, exposed to the outside the toner cartridge C through the openings <NUM> and <NUM> provided in the non-driving-side toner cartridge side cover <NUM>. Further, the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a are directed in the axial direction E, and in this embodiment, are directed toward the right end side. For this reason, each of a light incident direction on the light-emitting-side incident surface 1102a and a light emergent direction from the light-receiving-side emergent surface 1103a is a direction along the axial direction E.

Further, the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a are positioned in positions closer to the rear end portion <NUM> than to the front end portion <NUM> of the toner cartridge C with respect to the horizontal direction H. In this embodiment, the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a are positioned at an end portion of the toner cartridge C on an upstream side with respect to the mounting direction. Further, the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a are provided and arranged in the vertical direction V.

Thus, in this embodiment, positions of the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a are defined so that these positions are spaced from the toner discharge opening 31a and the residual toner receiving opening <NUM> with respect to the horizontal direction H. Further, the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a are positioned apart from the toner discharge opening 31a with respect to the axial direction E.

For this reason, it is possible to suppress that the toner leaked through the toner discharge opening 31a or the residual toner receiving opening <NUM> is deposited on the light-emitting-side incident surface 1102a or the light-receiving-side emergent surface 1103a.

Further, the toner discharge opening 31a and the residual toner receiving opening <NUM> are positioned on sides downstream of the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a with respect to the mounting direction. For this reason, when the mounting and demounting operation of the toner cartridge C is performed, the toner leaked toner the toner discharge opening 31a or the residual toner receiving opening <NUM> is not readily deposited on the light-emitting-side incident surface 1102a or the light-receiving-side emergent surface 1103a. That is, in the case where the positional relationship between these portions is reversed, for example, when the toner cartridge C is demounted, there is a possibility that the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a pass through a position where the toner leaked through the toner discharge opening 31a or the residual toner receiving opening <NUM> suspends, so that the toner is liable to be deposited on the light-emitting-side incident surface 1102a or the light-receiving-side emergent surface 1103a.

On the other hand, when the toner discharge opening 31a and the residual toner receiving opening <NUM> are positioned on the sides downstream of the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a with respect to the mounting direction, for example, when the toner cartridge C is demounted, the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a are positioned on sides downstream of the toner discharge opening 31a and the residual toner receiving opening <NUM> with respect to the demounting direction. For this reason, when if the toner is leaked through the toner discharge opening 31a or the residual toner receiving opening <NUM>, this toner is not readily deposited on the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a.

Thus, in this embodiment, even when the toner is leaked through the toner discharge opening 31a or the residual toner receiving opening <NUM>, this toner can be made hard to be deposited on the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a. For this reason, a lowering in detection accuracy of the light transmitting portion <NUM> due to deposition of the toner and the like can be suppressed, and a lowering in accuracy of full state detection of the residual toner amount in the residual toner accommodating portion 40a can be suppressed.

Further, in this embodiment, as described above, the light-emitting-side emergent surface 1102b and the light-receiving-side incident surface 1103b which are positioned inside the residual toner accommodating container <NUM> are disposed in the neighborhood of the residual toner receiving opening <NUM>. That is, the light-emitting-side emergent surface 1102b and the light-receiving-side incident surface 1103b are positioned on the front end portion <NUM> side of the toner cartridge C, which is a side where the residual toner receiving opening <NUM> is positioned, with respect to the horizontal direction H. Thus, the light-emitting-side emergent surface 1102b and the light-receiving-side incident surface 1103b are disposed in the neighborhood of the residual toner receiving opening <NUM>, so that full detection of the residual toner accommodating portion 40a can be accurately made as described above. Further, in such a constitution, the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a are spaced apart from the residual toner receiving opening <NUM> with respect to the horizontal direction H as described above, it is possible to compatibly realize that the accuracy in full (state) detection of the residual toner accommodating portion 40a is improved and that the toner is not readily deposited on the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a.

Incidentally, in this embodiment, the toner discharge opening 31a and the residual toner receiving opening <NUM> are disposed on the downstream side with respect to the mounting direction (axial direction D), and the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a are disposed on the upstream side with respect to the mounting direction (axial direction D), but the present invention is not limited to the constitution, and a reverse constitution may also be employed. When the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a are spaced from the toner discharge opening 31a with respect to the axial direction E and are spaced from the toner discharge opening 31a and the residual toner receiving opening <NUM> with respect to the horizontal direction H, the toner leaked through the toner discharge opening 31a or the residual toner receiving opening <NUM> can be made hard to be deposited on the light-emitting-side incident surface 1102a and the light-receiving-side emergent surface 1103a.

In the above-described embodiment, as the image forming apparatus, the laser printer was described as an example, but the image forming apparatus may also be an LED printer. The image forming apparatus forms an image on a recording medium (for example, sheet materials such as plain paper, a synthetic resin sheet which is a substitute for the plain paper, thick paper, a sheet for an overhead projector, and so on). Accordingly, the image forming apparatus in the present invention includes a copying machine, a printer, a facsimile machine, a multi-function machine having a plurality of functions of these machines.

Claim 1:
A toner cartridge (C) comprising:
a toner accommodating unit (<NUM>) including a first accommodating portion (<NUM>) and a second accommodating portion (<NUM>) and configured to accommodate toner, wherein the toner accommodating unit includes a first end portion and a second end portion on a side opposite from the first end portion with respect to a first direction and includes a third end portion and a fourth end portion on a side opposite from the third end portion with respect to a second direction crossing the first direction, wherein the first accommodating portion is on a side closer to the first end portion than to the second end portion in the first direction and the second accommodating portion is on a side closer to the second end portion than to the first end portion in the first direction, wherein the first accommodating portion is provided with a discharge opening (31a) for permitting discharge of the toner, accommodated in the first accommodating portion, to an outside of the toner cartridge, the discharge opening being in a position closer to the third end portion than to the fourth end portion in the second direction, and wherein the second accommodating portion is provided with a receiving opening (<NUM>) for receiving the toner from the outside of the toner cartridge to the second accommodating portion, the receiving opening being positioned closer to the third end portion than to the fourth end portion in the second direction; characterised by
a light transmitting portion (<NUM>) having an incident surface and an emergent surface, wherein the incident surface is configured so that light is capable of being incident from the outside of the toner cartridge into an inside of the second accommodating portion, wherein the emergent surface is configured so that the light incident into the inside of the second accommodating portion through the incident surface is capable of emerging to the outside of the toner cartridge, and wherein the incident surface and the emergent surface are provided in positions closer to the fourth end portion than to the third end portion in the second direction and are exposed to the outside of the cartridge.