Patent Application
20070292179
The present invention relates to an image forming apparatus, such as a copying machine or a printer, provided with a waste toner collecting means.
In a conventional image forming apparatus, e.g., a transfer type electrophotographic copying machine, toner used for development still remains in a small amount on a photosensitive drum as an image bearing member after a transfer operation. The transfer residual toner is removed from the photographic drum by a cleaning means. The thus removed toner is moved from the cleaning means to a waste toner-collecting container and contained in the collecting container as waste toner. In the waste toner-collecting container, it is desirable that the waste toner is contained in an amount as large as possible.
Japanese Patent Publication No. 3302579 has proposed a method of breaking piled waste toner collected and deposited by free fall in a waste toner-collecting container by moving a position of the collecting container in cooperation with insertion and removal of a sheet-feeding cassette.
Japanese Laid-Open Patent Application No. 2006-126434 has disclosed a constitution in which a waste toner accommodation efficiency is enhanced by imparting vibration to a waste toner-collecting container through impact during impingement of a vibrating lever against a cam member. This constitution includes a drive source for driving a feeding means for feeding a recording material, a driving force transmitting means for transmitting for transmitting a driving force during rotation in an opposite direction to rotation during the feeding of the recording material by the drive source, a vibration arm for imparting vibration to the waste toner-collecting container by the driving force transmitting means, and a guide means for guiding the vibration arm along a vibration direction. The drive source is rotated in the opposite direction for a predetermined time, so that vibration impartment to the waste toner-collecting container is effected by impact during the impingement of the vibration arm against the cam member.
In order to increase the toner accommodation efficiency of the waste toner-collecting container, provision of a toner-feeding member such as a screw has also been performed in general.
However, the waste toner has a high degree of aggregation, so that it is necessary to apply predetermined impact in order to break piled toner in the waste toner-collecting container. As a result, a noise of the impact is increased. For this reason, the impact noise is required to be suppressed to an acceptable level, so that it has been clarified that the piled toner cannot be completely broken.
The piled toner can also be broken by enhancing a feeding ability of the toner-feeding member. However, when the feeding ability is enhanced, the toner aggregates on one side of an inner space of the collecting container, so that an operational load of the toner-feeding member is increased.
A principal object of the present invention is to solve the above described problems.
An object of the present invention is to provide a cleaning apparatus and an image forming apparatus capable of breaking piled toner contained in a collecting container even when a toner feeding member has a low feeding ability.
According to an aspect of the present invention, there is provided a cleaning apparatus comprising:
a cleaning member for removing toner from an image bearing member;
a collecting container for collecting the toner removed by the cleaning member;
a feeding member, provided in the collecting container, for feeding the toner collected in the collecting member; and
vibrating means for imparting vibration to the collecting container.
These and other objects, features and advantages of the present invention will become more apparent upon a consideration of the following description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings.
FIGS. 3(a) and 3(b) are enlarged schematic sectional views, wherein
FIGS. 7 to 9 are schematic views each showing a vibrating mechanism portion.
FIGS. 11(a) and 11(b) are explanatory views each for a connecting operation between a catcher portion of a bottle and a connecting portion of a vibration arm.
(1) Image Forming Portion
This printer effects an image forming operation depending on input image information from an external host apparatus C communicatably connected with a control circuit portion (control board: CPU) B, thus being capable of forming and outputting a full-color image on a recording material. The external host apparatus C is a computer, an image reader, etc. The control circuit portion B sends a signal to the external host apparatus C, and receives a signal from the external host apparatus C. Further, the control circuit portion B effects image forming sequence control by sending signals to various image forming equipment and receiving signals from the various image forming equipment.
An intermediary transfer belt 8 which is an endless and flexible intermediary transfer member (hereinafter referred to as a “belt”) is stretched among a secondary transfer opposite roller 9, a turn roller 10, and a tension roller 11 and rotationally driven in a counterclockwise direction indicated by an arrow at a predetermined speed by rotating the secondary transfer opposite roller 9. A secondary transfer roller 17 is pressed against the secondary transfer opposite roller 9 via the belt 8. A contact portion between the belt 8 and the secondary transfer roller 17 is secondary transfer portion.
Four (first to fourth) image forming portions 1Y, 1M, 1C and 1Bk are disposed in series below the belt 8 with a predetermined spacing along a belt movement direction. Each image forming portion is an electrophotographic process mechanism of a laser exposure type and includes a drum-type electrophotographic photosensitive member 2 as an image bearing member (hereinafter referred to as a “drum”) and is rotationally driven in a clockwise direction indicated by an arrow at a predetermined speed. Around each of drums 2, a primary charger 3, a developing apparatus 4 as a toner image forming means, a primary transfer roller 5, and a drum cleaning apparatus 6 as a first cleaning means are disposed. Each primary transfer roller 5 is disposed inside the belt 8 and is pressed against an associated drum 2 via a lower portion of the belt 8. A contact portion between each drum 2 and the belt 8 is a primary transfer portion. A laser exposure apparatus 7 is used for exposing a surface of the drum 2 to laser light and constituted by a laser emitting means for emitting light in correspondence with a time-serial electric digital pixel signal as input image information, and mirrors such as a polygon mirror, a reflection mirror, etc.
The control circuit portion B actuates each image forming portion to form an image on the basis of a color separation image signal inputted from the external host apparatus C. As a result, at the first to fourth image forming portions 1Y, 1M, 1C and 1Bk, color toner images of yellow, magenta, cyan, and black are formed, respectively, on an associated surface of rotating drum 2 at a predetermined timing. A method of forming a toner image on the drum will be described. The drum 2 is electrically charged uniformly by the primary charger 3 and is imagewise exposed to light emitted from the laser exposure apparatus 7 to form thereon an electrostatic latent image. On the basis of the formed electrostatic latent image, a toner image is formed by the developing apparatus 4. The toner image is transferred onto the belt 8 by the primary transfer roller 5. The toner remaining on the drum 2 after the transfer is removed by the cleaning apparatus 6. This image forming step is common to all the colors.
Each color toner image formed on the surface of the drum 2 at each image forming portion is successively transferred onto an outer surface of the belt 8, which is rotationally driven in the direction identical to the rotation direction of an associated drum 2 at a speed corresponding to the rotation speed of the associated drum 2, in a superposition manner at an associated primary transfer portion. As a result, on the surface of the belt 8, an unfixed full-color toner image consisting of superposed four color toner images is formed.
At a predetermined sheet feeding timing, a pickup roller is driven, so that a sheet of the recording material P stacked and contained in the sheet feeding cassette 13 is separated and fed to a registration roller pair 16 through a vertical sheet feeding path 15.
The registration roller pair 16 feeds the recording material P at a timing so that a leading end of the recording material P reaches the secondary transfer portion in synchronism with a timing at which a front end of the unfixed full-color toner image on the rotating belt 8 reaches the secondary transfer portion. As a result, at the secondary transfer portion, the unfixed full-color toner image on the belt 8 is successively secondary-transferred collectively onto the surface of the recording material P. The recording material coming out of the secondary transfer portion is separated from the surface of the belt 8 and guided by a vertical guide 18 into a fixing roller pair (hot-press roller pair) of a fixing apparatus 19. By the fixing apparatus 19, the unfixed full-color toner image is melted and color-mixed under application of heat and pressure to be fixed on the recording material surface as a permanently fixed image. The recording material P coming out of the fixing apparatus 19 is sent onto a sheet discharge (output) tray 24 as a full-color image formation product through an inner sheet discharging and feeding roller pair 20, a sheet feeding path 21, a sheet discharging and feeding roller pair 22, and a sheet discharging port 23.
The surface of the belt 8 after the separation of the recording material 9 is cleaned by removing a residual deposition on matter such as secondary-transfer residual toner or the like from the belt 8 by a belt cleaning apparatus 12 as a second cleaning means and is then repetitively subjected to image formation.
In the case of a monochromatic print mode, control of the image forming operation is effected with respect to only the fourth image forming portion 1Bk for forming the black toner image.
In each of the first to fourth image forming portions 1Y, 1M, 1C and 1Bk, four members including the drum 2, the primary charger 3, the developing apparatus 4, and the drum cleaning apparatus 6 are integrally formed into a unit as a process cartridge collectively detachably mountable in a main assembly of the printer.
Drive sources for the printer is not shown in
(2) Collection of Waste Toner
Collection of waste toner from the drum cleaning apparatuses 6 of the respective image forming portions 1Y, 1M, 1C and 1Bk and the belt cleaning apparatus 12 will be described.
In the following description, a longitudinal direction is a direction parallel to a rotation axis direction of the drum 2. Further, the terms “front”, “rear”, “left” and “right” are used on the basis of location of the printer when viewed from the front.
In this embodiment, the drum cleaning apparatus 6 at each image forming portion is of a blade type. The drum cleaning apparatus 6 includes, as shown in
In this embodiment, the belt cleaning apparatus 12 is also of a blade type. The belt cleaning apparatus 12 includes, as shown in
In the main assembly of the printer, a long waste toner feeding pipe (means) 25 as shown in
Further, on the left-hand end portion side in the main assembly of the printer, a toner-collecting container (waste toner bottle; hereinafter referred to as a “bottle”) 27 as shown in
The bottle 27 is mounted on and demounted from the main assembly of the printer through an opening 62 provided to a left-side surface plate 61 of the printer main assembly as shown in
The joint portion 26 is attached to the front end portion of the pipe 25 and has a downward toner discharge portion. At a lower surface of the joint 26, a thick elastic sealing member 26a (
When the bottle 27 is pulled out, from the right direction to the left direction, from the printer main assembly while sliding on the mounting table 63, the opening 27a on the upper surface of the bottle 27 comes out of the lower surface of the joint portion 26 against the elasticity of the elastic sealing member 26a, thus being disconnected from the joint portion 26. That is, only the bottle 27 is demounted from the inside of the printer main assembly.
(3) Improvement in Toner Accommodation Efficiency of Bottle 27
The piled the toner deposited in the bottle 27 by the free fall of the waste toner discharged from the front end portion of the pipe 25 into the bottle 27 through the joint portion 26 and the opening 27a is broken, so that it is possible to improve a waste toner accommodation efficiency of the bottle 27. For this reason, in the printer of this embodiment, the toner feeding member is provided in the bottle 27 and a vibration imparting means for vibrating the bottle is also provided. More specifically, the piled the deposition toner in the bottle 27 is broken by a vibration imparting operation of the vibration imparting means and a reciprocating operation for vibration impartment at this time is changed to a rotation operation in one direction to rotate the toner feeding member in the bottle 27, so that the piled toner which cannot be completely broken by the vibration imparting operation is broken and fed. As a result, it is possible to not only reduce a drive noise but also improve the waste toner accommodation efficiency of the bottle 27.
(3-1) Toner Feeding Member in Bottle
As shown in
As described later, the screw shaft 31 is rotated to fluidize the toner in the bottle 27, thus causing an occurrence of breakage of the piled toner deposited in the bottle 27.
(3-2) Bottle Vibration Imparting Means
In
The intermediary gear 42 is engaged with a one-way clutch gear 44 which is idled above a gear supporting shaft during the normal rotation drive of the registration motor M. For this reason, a drive gear 45 integrally supported by the gear supporting shaft is not rotated.
When the registration motor M is reversely driven rotationally, the one-way clutch gear 44 is reversely rotated. A direction of the reverse rotation is a direction in which the clutch gear 44 is engaged with the gear supporting shaft, and the drive gear 45 is rotated together with the clutch gear 44 engaged with the gear supporting shaft. A rotation force of the drive gear 45 is transmitted to a cam gear 48 through intermediary gears 46 and 47, so that the cam gear 48 is rotationally driven.
At a side surface of the cam gear 48, an eccentric cam 49 is provided integrally with the cam gear 48. A vibration arm 50 which is an L-shaped flat plate is vertically movable by being guided by a vertically elongated hole a and a pin shaft b engaged in the hole a. The vibration arm 50 has a cam engaging concave portion 50a at an upper end portion thereof so that the recessed portion 50a has a horizontally concavely curved surface which conforms to a shape of the eccentric cam 49, so that the cam engaging recessed portion 50a is engaged with the eccentric cam 49. Further, at a lateral end portion of the vibration arm 50, a cylindrical connecting portion 50b is provided. Accordingly, the cam gear 48 is rotationally driven to cause eccentric rotation of the eccentric cam 49, so that the vibration arm 50 is vertically reciprocated with a stroke corresponding to a degree of eccentricity of the eccentric cam 49.
The above described registration motor M, gear train 41 to 49, and vibration arm 50 are supported by a vertical supporting plate (not shown) in a predetermined arrangement.
(3-3) Connection Between Bottle 27 and Vibration Arm 50
The catcher portion 35b provided to the bottle lever 35 on the bottle 27 side is detachably engaged with the cylindrical connecting portion 50b, so that the bottle 27 and the vibration arm 50 are connected to each other.
More specifically, as described above with reference to
A connecting operation in this case will be described with reference to FIGS. 11(a) and 11(b).
Both of a height position of the catcher portion 35b on the bottle 27 side and a height position of the connecting portion 50b on the vibration arm 50 side are not constant as to where these positions are located in a movable area.
However, as shown in
Next, as shown in
As described above, even when the height position of the catcher portion 35b on the bottle lever 35 side end the height position of the connecting portion 50b on the vibration arm 50 side are located at any positions, the bottle lever 35 and the vibration arm 50 are connectable to each other.
Demounting of the bottle 27 from the printer main assembly is performed by pulling the bottle 27 from the right direction to the left direction toward the outside of the printer main assembly while the bottle 27 is caused to slide on the mounting table 63. As a result, the opening 27a on the upper surface of the bottle 27 and the joint portion 26 are disconnected from each other and at the same time, the C-shaped portion of the catcher portion 35b on the bottle 27 side is opened against the elasticity thereof by a pulling force, thus being disengaged from the connecting portion 50b of the vibration arm 50. As a result, the engagement between the bottle 27 and the vibration arm 50 is released.
(3-4) Vibration Imparting Operation and Drive of Screw Shaft in Bottle
As described above, the registration motor M is controlled by the control circuit portion B during the image forming operation of the printer so that it is normally rotated and the normal rotation is stopped so as to convey the recording material P to the secondary transfer portion at a predetermined timing by the registration roller pair 16. The one-way clutch gear 44 is rotated during the normal rotation of the motor M but the rotation direction is an idling direction in which the gear 44 is idled above the gear supporting shaft, so that the drive gear integrally supported by the gear supporting shaft is not rotated. In other words, the vibration impartment to the bottle 27 by the vertical reciprocating motion of the vibration arm 50 and the drive of the screw shaft in the bottle 27 are not performed.
With the image forming operation of the printer, the toner collected in the bottle 27 is deposited in a deposition shape as indicated by a broken line a in
For this reason, in the printer of this embodiment, not only the screw shaft 31 but also the vibration imparting means for vibrating the bottle 27 are provided in the bottle 27 as described above. During non-image formation of the printer, the piled toner deposited in the bottle 27 is broken by the vibration impartment operation. At the same time, the reciprocating operation by the vibration impartment is changed to the rotating operation in one direction to rotate the toner feeding screw shaft 31 in the bottle 27, so that the piled toner which cannot be completely broken by the vibration imparting operation is further broken and fed. As a result, the drive noise is reduced and the waste toner accommodation efficiency is increased.
The control circuit portion B is programmed so that it can control the registration motor M so as to be reversely rotated only for a predetermined time during the predetermined period of control timing when the printer is placed in the non-image formation state. By this reverse rotation control of the registration motor M, the drive gear 41 is rotated in the clockwise direction indicated by an arrow Y in
During the upward rotational movement of the bottle lever 35 with the upward movement of the vibration arm 50, the bottle lever 35 is stuck against and stopped by the upper-side stopper portion 36. By further upward movement of the vibration arm 50, the front side of the bottle 27 is raised by the bottle lever 35 struck against the upper-side stopper portion 36, so that a bottom surface of the bottle 27 is moved upwardly from the mounting table 63 with a rear bottom end of the bottle 27 as a fulcrum as shown in
As described above, by the vertical reciprocating motion of the vibration arm 50, the bottle 27 is vertically swung. By this vibration imparting operation, the piled toner deposited in the bottle 27 is caused to be broken.
The upper surface opening 27a of the bottle 27 and the joint portion 26 of the pipe 25 are connected through the thick elastic sealing member 26a. For this reason, the vertical movement of the upper surface opening 27a of the bottle 27 by the vibration imparting operation is performed with the elastic sealing member 26a as a cushion member against the joint portion 26. Accordingly, a sealing state between the upper surface opening 27a of the bottle 27 and the joint portion 26 is not broken during the vertical movement of the bottle 27 by the vibration imparting operation.
Further, with the vertical reciprocating motion of the vibration arm 50, the bottle lever 35 is vertically moved rotationally between the upper-side stopper portion 30 and the lower-side stopper portion 27 with the supporting shaft 34 as a center. As a result, the bottle gear 33 is normally rotated and reversely rotated by the sector gear 35a integrally supported with the bottle lever 35. During the upward rotational movement of the bottle lever 35 from the lower-side stopper portion 37 toward the upper-side stopper portion 36, the bottle gear 33 is normally rotated in the clockwise direction indicated by a solid line in
More specifically, in the vertical reciprocation motion of the vibration arm 50, the screw shaft 31 in the bottle 27 is rotationally driven during the downwardly rotational movement of the bottle lever 35 from the upper-side stopper portion 36 toward the lower-side stopper portion 37 by the downward movement of the vibration arm 50. By this rotation of the screw shaft 31, the piled toner which cannot be completely broken by the vibration imparting operation is broken and fed.
As described above, in a predetermined period during the non-image formation of the printer, the registration motor M is controlled so as to be reversely rotated, so that the vertical reciprocating motion of the vibration arm 50 imparts vibration to the bottle 27. The reciprocating operation by the vibration impartment is changed to the rotational operation in one direction, so that the toner feeding screw shaft 31 in the bottle 27 is rotated to break and feed the piled toner which cannot be completely broken by the vibration imparting operation.
In the case of only the vibration imparting operation referring to
Further, in the case of only the rotation of the screw shaft 31, referring to
In this embodiment, however, the vibration imparting operation and the toner feeding by the screw shaft 31 in the bottle 27 are performed at the same time, whereby the piled toner which cannot be completely broken by the vibration imparting operation is further broken and fed effectively. As a result, referring to
There is a possibility that the vibration by the vibration impartment to the bottle 27 adversely affects the image formation, so that the vibration impartment may desirably be performed during a period of the non-image formation. More specifically, the vibration impartment is performed after the image is fixed on the recording material P. The vibration impartment is effective when it is performed periodically, i.e., depending on frequency in use of the printer. For example, the vibration impartment is performed after a predetermined number of image formation is effected. Further, it is also possible to perform the vibration impartment after consumption of a predetermined amount of toner is confirmed by integrating an image duty.
Herein, as the period of the non-image formation, there are a premulti-rotation period, a standby period, a pre-rotation period, and a post-rotation period of the image forming apparatus. More specifically, the premulti-rotation period is an actuating operation period of the image forming apparatus after a main power switch of the image forming apparatus is turned on. The standby period is a period for awaiting input of an image formation start signal. The pre-rotation period is a pre-operation period for performing a pre-operation after the image formation start signal is inputted and before an image forming operation is started. The post-rotation period is a post-operation period for performing a post-operation after the image forming operation is completed and before the image forming apparatus is placed in a standby state.
During the non-image formation period, the recording material P is not interposed between the registration rollers 16, so that there is no problem even when the registration rollers 16 are reversely rotated by the reverse rotation control of the registration motor M. In other words, there is no problem for utilization of the reverse rotation of the registration roller driving motor M in vibration impartment.
However, in the case where the recording material P is interposed between the registration roller 16 at the time of an occurrence of jamming or the like even during the non-image formation period, the vibration impartment is not performed even when a vibration impart condition is satisfied. In this case, the vibration impartment is performed during a restoring operation after the jammed recording material P is removed.
In this embodiment, such a constitution that the vibration is imparted by reversely rotating the motor M for driving the registration rollers 16 is described above. However, other than the registration rollers 16, it is also possible to utilize, as a drive source for the vibrating means for the vibration arm, a drive source for driving conveyance rollers which do not convey the recording material P when the rollers are reversely rotated during the non-image formation period. For example, it is possible to employ a constitution in which the vibrating means is driven by utilizing reverse rotation of a fixation motor or a sheet discharge motor. It is also possible to provide a motor dedicated solely to the vibration impartment.
According to this embodiment, it is possible to achieve the following effects a to c.
a: It is possible to reduce the impact noise by realizing the vibration imparting operation through the operation interrelated with the eccentric cam, not through the impact by impingement between parts.
b: it is possible to complement a lowering in the toner feeding performance at the inner corner portions of the bottle when the screw blade does not affect in the case where the screw shaft is used as the toner feeding member in the bottle.
c: The L-shaped flat plate member (vibration arm) 50 is used for transmitting a driving force for imparting vibration, so that it is possible to reduce an arrangement space for the driving force transmitting means such as the gear train for driving the screw shaft 31 in the bottle 27 and reduce the number of parts. As a result, it is possible to improve design flexibility and reduce parts cost.
In
Similarly as in Embodiment 1, with the reciprocating motion of the vibration arm 50, the bottle lever 35 (engaging member) connected to the connecting portion 50b of the vibration arm 50 via the catcher portion 35b is vertically moved rotationally about the supporting shaft 34.
Further, by the vertical reciprocating motion of the vibration arm 50, the bottle 27 is vertically swung. By this vibration imparting operation, the piled toner deposited in the bottle 27 is caused to be broken.
Further, with the vertical reciprocating motion of the vibration arm 50, the bottle lever 35 is vertically moved rotationally between the upper-side stopper portion 30 and the lower-side stopper portion 27 with the supporting shaft 34 as a center. During the upward rotational movement of the bottle lever 35 from the lower-side stopper portion 37 toward the upper-side stopper portion 36, the claw portion 35c is rotated in the counterclockwise direction indicated by a solid line in
More specifically, in the vertical reciprocation motion of the vibration arm 50, the screw shaft 31 in the bottle 27 is rotationally driven during the downwardly rotational movement of the bottle lever 35 from the upper-side stopper portion 36 toward the lower-side stopper portion 37 by the downward movement of the vibration arm 50. By this rotation of the screw shaft 31, the piled toner which cannot be completely broken by the vibration imparting operation is broken and fed.
In this embodiment, instead of the one-way clutch mechanism used in Embodiment 1, the claw gear mechanism 35c and 33A is used. As a result, the image forming apparatus of this embodiment is reliably operable even in an environment in which scattered toner is deposited, thus achieving similar effects to those in Embodiment 1.
In Embodiments 1 and 2, the constitutions of the image forming apparatuses capable of effecting color print are described but the present invention is widely applicable to image forming apparatuses including waste toner collecting means, thus being also applicable to a white/black (monochromatic) image forming apparatus.
In the above described embodiments, the operation of the feeding member in the waste toner-collecting container is interrelated with the operation of the vibrating means. However, in the present invention, the operation of the feeding member may be performed independently of the operation of the vibrating means.
As described above, according to the present invention, the piled waste toner deposited in the collecting container is broken by the vibration imparting operation suppressed in impact noise and the vibration imparting operation is changed to the rotation operation in one direction to rotate the toner feeding member in the collecting container. By this rotation, the piled toner which cannot be completely broken by the vibration imparting operation is broken and fed effectively. As a result, it is possible to provide an image forming apparatus including a waste toner collecting means which is reduced in drive noise and improved in toner accommodation efficiency.
While the invention has been described with reference to the structures disclosed herein, it is not confined to the details set forth and this application is intended to cover such modifications or changes as may come within the purpose of the improvements or the scope of the following claims.
This application claims priority from Japanese Patent Application No. 168714/2006 filed Jun. 19, 2006, which is hereby incorporated by reference.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2006-168714 | Jun 2006 | JP | national |
