JP4847137B2 - Powder container / toner container / image forming device - Google Patents

Description

  The present invention relates to a powder container for collecting and storing powder such as toner, and an image forming apparatus such as a copying machine, a printer, a facsimile, and a plotter having the powder container.

  In an image forming apparatus such as a copying machine, the transfer residual toner remaining on the photosensitive drum or intermediate transfer belt after the toner image is transferred to a recording medium or intermediate is removed by a cleaning mechanism and collected in a powder recovery box. Centralized and accumulated.

  This type of powder recovery box includes a toner inlet connected to a cleaning mechanism, a toner transport unit that transports toner put in the box, and a toner that detects the degree of toner storage (filling rate) in the box. A detection means is provided.

  When the toner detection means detects that the box is full of toner, the powder recovery box is replaced.

  From the viewpoint of improving user convenience, it is better to reduce the number of replacements of the powder collection box as much as possible. For this purpose, it is desirable to increase the capacity of the box as much as possible.

  However, in this type of image forming apparatus, as is well known, downsizing and cost reduction have progressed, and the actual situation is that it is not allowed to enlarge the box only from the viewpoint of improving the powder recovery.

  In general, the powder collection box is often arranged using a so-called dead space such as a space between a paper feeding unit arranged at the bottom of the image forming apparatus main body and an image forming unit located above the sheet feeding unit.

  As a configuration of the powder collection box, there is a configuration in which a toner conveying unit is provided in a box-shaped toner cartridge (for example, Patent Document 1). In this configuration, an eccentric cam is provided on the shaft of the screw that replenishes toner to the outside, and the flat plate is reciprocated in the horizontal direction by the eccentric cam, and a C-shaped inward projection formed integrally with the flat plate. The toner is conveyed. Further, a configuration for detecting the remaining amount of toner is provided in the cartridge.

On the other hand, it is important that the toner introduced into the developing device to be used for development does not cause supply failure by smooth movement. However, some of the accommodated toner is solidified to cause a so-called blocking phenomenon, and smooth movement may be hindered.
Therefore, conventionally, a configuration for loosening the toner causing such blocking has been proposed (for example, Patent Document 2). In this configuration, a reciprocally movable plate member disposed in the developing container is disposed, and the plate member is provided with a toner inflow port and a protruding portion that enters the inflowing toner to reciprocate the plate member. In some cases, the toner may be loosened by the protrusions.

JP-A-11-002947 JP-A-10-207202

  However, when there is no room in the height direction of the image forming apparatus main body from the viewpoint of miniaturization, the dimensional ratio of the powder recovery box is inevitably large in the vertical and horizontal directions (X and Y directions), and the height direction (Z direction). ) Must be small. That is, it tends to be a flat box shape that is wide in the horizontal direction and small in height.

  In such a box shape, it is very difficult to accumulate toner uniformly, and there is a possibility that the toner is partially solidified and accumulated. When toner is solidified and accumulated around the toner detection means, the entire box is not full, but full detection is performed, and the replacement operation is requested early in a non-full state, resulting in a decrease in user convenience. It will be.

  The technique disclosed in Patent Document 1 aims to efficiently replenish toner to the end while preventing aggregation of the toner previously stored in the cartridge. As shown in FIG. 7 of the same document, the conveying direction of the protrusion as a member is different from each other, but the toner is unidirectionally directed to the toner detecting means by the interaction.

  Therefore, when this conveying method is applied to the powder recovery box, the toner is easily solidified and accumulated around the toner detecting means, and the above-described problem of erroneous detection cannot be solved.

  On the other hand, in the technique disclosed in Patent Document 2, the introduced toner can be moved by being pushed and moved by a reciprocating plate member. However, the introduced toner has the largest amount on the introduction side, and is introduced. As the sheet is sequentially moved from the section, the amount of the plate member that is pushed and moved is reduced by leveling in the internal space, and the amount of the toner detecting means may be decreased. For this reason, if the amount of toner collected in the powder collection box is the largest in the vicinity of the inlet and gradually accumulates in the process from this position to the position of the toner detection means, a new powder collection Even if a situation occurs that hinders the movement of the toner to be introduced into the box, this state cannot be detected by the toner detection means. For example, even when the toner is full, it cannot be detected. There is a possibility that the vicinity of the inlet of the powder collection box overflows and the vicinity of the grounding portion of the powder collection box is soiled.

  As described above, if the behavior of the toner in the powder recovery box is not appropriate, there may be a case where an accurate full state cannot be determined even if a powder detection unit for detecting the full state is provided.

  The present invention can freely control the flow and amount of powder such as toner, and can accurately detect the actual condition of the collected toner, thereby reducing the false detection of the powder detection means and improving the convenience for the user. The main object of the present invention is to provide a powder container that can contribute to the above and an image forming apparatus having the same.

  According to the present invention, the clogging of toner in each region is provided by providing regions having different functions in the process of moving the powder in the container by changing the transport direction and transport amount at each position of the powder transport unit. This is based on the idea that the powder detection means is finally filled with powder so that full detection by the powder detection means can be accurately performed.

Specifically, in the powder container in which the invention according to claim 1 uses a box in which the size in the thickness direction perpendicular to the vertical and horizontal directions is reduced,
A powder inlet provided in the box ;
A powder conveying means for moving the powder introduced from the powder inlet portion toward a powder detection portion for detecting powder fullness provided in the box;
The powder conveying means is
A stirring member provided with a conveying member configured in parallel with a plurality of barrier plates that are partitioned in a rectangular shape by the ribs that run in the vertical and horizontal directions and have an angle in the vertical and horizontal directions and can move the powder;
An eccentric cam accommodated in a receiving part integrated with the stirring member and capable of moving the stirring member in the reciprocating direction and the height direction;
Means for driving the eccentric cam,
The stirring member supports the lower surface in the thickness direction by a support member disposed near the powder detection unit between the powder inlet and the powder detection unit in the reciprocating motion direction by the eccentric cam. Thus, the conveying direction of the powder is changed during the reciprocating motion with the support member as a boundary .

According to a second aspect of the present invention, in the powder container according to the first aspect, the agitating member scoops the powder from the bottom to the upper side on the one side and the other side during the reciprocating motion. Is characterized in that the powder is scraped from the top to the bottom, and the conveying direction of the powder is opposite .

According to a third aspect of the present invention, in the powder container according to the first or second aspect, the agitation member causes the powder to be detected by the powder detection unit when scooping the powder from the bottom to the top during the reciprocating motion. It is characterized in that the powder is leveled when the powder is conveyed upward and the powder is scraped from the top to the bottom .

The invention of claim 4, wherein, in the powder container of Claim 1 Symbol placement, stirring member having the above powder conveying means, said weir plate portion, in a direction which can be moved while pressing scooping the toner on the forward pass It is characterized by being tilted .

According to a fifth aspect of the invention, in the powder container of claim 1 Symbol placement, stirring member having the above powder conveying means, said sheathing board portion, and the conical cone having a vertical surface facing outward It is characterized by being.

The invention described in claim 6 is characterized in that the powder container according to one of claims 1 to 5 is used as a toner container .

The invention described in claim 7 is characterized in that the toner container described in claim 6 is used in an image forming apparatus.

  According to the present invention, it is possible to control the state of powder filling in a container by eliminating the blocking phenomenon and lump of powder such as toner contained in a narrow space and controlling the movement state. The powder detection unit detects the full state before the container is full so that the powder detection unit can be filled with powder in the last order by preventing uneven distribution It is possible to improve detection accuracy by eliminating erroneous operations.

  The best mode for carrying out the present invention will be described below with reference to the illustrated embodiments.

  First, the overall configuration of an image forming apparatus equipped with a toner container having a powder container according to this embodiment will be described with reference to FIG.

  In the image forming apparatus 1 shown in FIG. 1, the exposure unit 3 performs optical writing on the four image forming units 4, 5, 6, and 7 arranged in parallel in the substantially horizontal direction to form an electrostatic latent image. The Each electrostatic latent image is visualized by developing means of each image forming unit.

  The toner images formed on the image forming units are sequentially transferred onto the intermediate transfer belt 8 in a superimposed manner. The transfer paper loaded in the paper feed cassette 1 is fed by the paper feed roller 2, and after correcting the oblique shift by the registration roller pair 9, is sent to the secondary transfer portion at a predetermined timing. The superimposed toner images on the intermediate transfer belt 8 are collectively transferred onto the transfer paper by the secondary transfer roller 10 at the secondary transfer site.

  Thereafter, the color toner image is fixed as an image on the transfer paper by the fixing unit 11 and is discharged as an output image to the paper discharge tray 15 on the upper surface of the apparatus by the paper discharge roller pair 12.

  The transfer residual toner on the intermediate transfer belt 8 is removed from the belt by the cleaning mechanism 13 and accumulated in a toner storage box 14 as a powder container.

  In recent years, even in such an image forming apparatus, downsizing and cost reduction have been advanced. There is also a need for improved user convenience.

  Therefore, it is desirable to increase the capacity of the box as much as possible in order to improve user convenience and reduce the number of times the powder box is replaced. However, it does not allow the size of the machine to increase. Therefore, it is often the case that the powder box is arranged in a form that fills the dead space in the machine configuration.

  In the image forming apparatus of this embodiment, the space from the paper feed roller 2 to the secondary transfer roller 10 needs to be separated to some extent due to the transfer paper transfer relationship, and a dead space is likely to occur. Often a powder container is installed.

  However, when the above-described configuration is adopted, the following problems occur as described above.

  Since the dimensional ratio of the powder box is large in the X and Y directions and small in the Z direction, it is very difficult to accumulate toner uniformly. If it is partially solidified and accumulated, the powder (hereinafter also referred to as “toner”) will be clogged without being conveyed, causing inconvenience to other parts, or full detection of powder capacity (full detection) There arises a disadvantage that the detection accuracy is remarkably deteriorated.

  According to the study by the present inventors, it is necessary to create a plurality of flows in different directions at different positions on the horizontal plane in order to control the powder so that it can be accumulated uniformly.

  In order to achieve this, for example, as shown in FIG. 8, the toner stirring rod 17 is disposed so as to cover the entire area of the bottom surface of the powder box 100, or as shown in FIG. A configuration in which a plurality of lines are arranged can be considered.

  However, in such a system, the configuration for driving the stirring means such as the toner stirring rod 17 and the conveying screw 18 becomes complicated, and it must be expensive. That is, in order to simultaneously rotate a plurality of stirring means in different directions, a complicated gear train is required.

  Even in this case, since the toner conveyance direction is simply reversed, it is difficult to finely control the toner flow and flow amount, and the powder full capacity detection accuracy is still low. The problem cannot be solved.

  In the present embodiment, in view of the above circumstances, the flow and amount of toner can be controlled easily and with high accuracy with a simple configuration, and the toner can be reliably moved to the position of the powder full detection means. An object of the present invention is to provide a powder container that can increase the accuracy of full detection.

  As shown in FIG. 2, a toner storage box 14 as a powder container used in the present embodiment includes an upper case 21 having a powder inlet portion 20 as a powder inlet portion, a lower case 22, and a powder. It has a full detection unit 23 and the like. A powder transfer hose (not shown) extending from the cleaning mechanism 13 is connected to the powder inlet 20 and the powder is charged.

  As shown in FIG. 3, the lower case 22 accommodates a powder transport unit 24 as a powder transport unit. As indicated by an arrow 25, the powder conveying means 24 is fixed to one end of the stirring plate 26, the cam shaft 27, and the cam shaft 27 that reciprocates substantially in the horizontal direction. A drive gear 28 connected to the cam shaft 27, an eccentric cam 30 provided in the other end portion of the cam shaft 27 and housed in a cam receiving portion 29 formed integrally with the stirring plate 26.

  The cam shaft 27 is supported by a plurality of support pieces 31 formed integrally with the stirring plate 26. The camshaft 27 is divided on the drive gear 28 side and is connected by a coupling 32.

  The powder full detection unit 23 includes powder full detection means 34 as powder detection means. As the powder full detection means 34, for example, a light reflection type photosensor can be used.

  The stirring plate 26 is integrally formed of a synthetic resin, and has a plurality of conveying portions 33A, 33B, 33C,... 33P arranged at different positions on a substantially horizontal plane. Each conveying portion 33 is partitioned into a rectangular shape by ribs running vertically and horizontally, and has an angle on a substantially horizontal plane with respect to the moving direction of the powder conveying means 24 (reciprocating direction indicated by the arrow 25). It is formed with the conveyance member (33Fa in the case of the conveyance part 33F) which put in parallel the some dam plate part which can be moved.

  The respective conveying members are arranged obliquely at substantially equal intervals, and a groove is formed between the respective conveying members.

  Each transport unit 33 is composed of, for example, a 33H type and a 33K type having a different transport direction.

  In the transport units 33A, 33B, 33H, 33M, 33N, and 33P, the toner transport direction is the direction indicated by the solid line arrow, and in the transport units 33C, 33D, 33E, 33F, 33G, 33I, 33J, 33K, 33L, and 33P, the dashed arrow It becomes the direction shown by. In other words, the direction in which the toner is pushed and moved is different between the transport units 33A to 33P.

  Among these, for example, the conveyance direction of the conveyance units 33A, 33B, 33M, 33N, 33P, and 33G is a direction approaching the powder full detection means 34. For example, the conveyance direction of the conveyance units 33J, 33K, and 33L is powder full. This is the direction away from the detection means 34.

  A partition plate 35 extending along the cam shaft 27 is integrally formed on the upper surfaces of the transport portions 33N and 33P. The partition plate 35 regulates the flow of powder on the upper portions of the transporting portions 33N and 33P.

  Each of the above-mentioned conveying units has different intervals between barrier plates that can be used to push and move the toner, so that the amount of toner that moves through the conveying unit is different. That is, when the interval between the dam plate portions is increased, the amount of toner entering between the dam plate portions is larger than when the interval between the dam plate portions is small.

  In addition, a partition plate 36 extending in a direction orthogonal to the cam shaft 27 is integrally formed between the transport units 33F and 33G and the transport units 33J and 33M. The partition plate 36 regulates the flow and flow amount of the upper and lower powders between the transport units 33F and 33G and the transport units 33J and 33M. These partition plates 35 and 36 are disposed at positions that abut against the toner flow generated by the transport unit.

The powder conveying means 24 used in the conveying structure of the conveying unit in this embodiment is configured to reciprocate by a driving mechanism having the configuration shown in FIG. 4, and the movement form is different between the forward path and the backward path. It is.
The above-described motion form is realized by making the movement trajectory different between the forward path and the return path, and the height direction and the inclination correspond to the movement trajectory.

  Since the movement forms are different in this way, the shape of the conveyance surface provided for conveyance in the powder conveyance unit 24 is different between the forward path and the backward path, and the inclination of the forward path and the backward path is different, so Breaking down and transporting in the moving direction (pressing and moving the toner in the forward path) can be performed efficiently. Hereinafter, this configuration will be described with reference to FIG.

  In FIG. 4 (schematic cross-sectional view seen from the drive gear 28 side), when the cam shaft 27 rotates with the large-diameter portion of the eccentric cam 30 facing downward, the stirring plate 26 causes the eccentric cam to the cam receiving portion 29. In accordance with the phase of the large-diameter portion of 30, first, it moves to the left in the figure so as to float upward as indicated by arrow A, then descends while slightly retracting, as indicated by arrow B, and then by arrow C As shown in the figure, the robot moves backward substantially horizontally, and then moves diagonally upward while moving backward slightly as indicated by an arrow D, and repeats these operations to perform a substantially reciprocating motion as a whole. As a result, at the time of forward movement (the direction indicated by reference numeral C in FIG. 4), the agitating plate 26 moves along the bottom surface of the case 22 so that the conveyance unit 33 can push the toner and move backward. At that time (directions indicated by symbols D and A in FIG. 4), the agitating plate 36 is lifted from the bottom surface of the case 22 so that the transport unit 33 is also lifted and moved away from the pushed toner. In other words, the toner is moved in a state where the toner is not returned, in other words, in a state where the toner is stopped at the pushed position.

  The motion form of the stirring plate 26 appears as a difference in inclination between the forward path and the return path as indicated by symbols A to D, and a difference in the height direction obtained from the difference in inclination. Note that the rotational speed of the eccentric cam 30 may be different between the forward path and the backward path of the stirring plate 26. In this case, the moving speed on the backward path corresponding to the motion form that does not contribute to the toner phase is different from that of the forward path. The toner movement can be speeded up by increasing the speed.

  According to such a transport structure in the transport unit, a plurality of transport units 33 having different transport directions can be simultaneously reciprocated by a single drive source without using a gear train.

  When the agitating plate 26 performs reciprocating motion, the flow is different in each transport unit, but as shown in FIG. 5, a transport flow as shown by a thick black arrow is generated as a whole, resulting in a transport flow. A plurality of regions are formed along the line. That is, the plurality of areas are the area a1 defined by the partition plates 35 and 36, the area a2 near the powder inlet part 20, the area a3 near the cam receiving part 29, and the last area in the order of the conveyance flow. An area a4 facing the powder full detection means 34 is set. Of these areas, the area a1 close to the powder inlet 20 is the inlet area, the area a4 facing the powder full detection means 34 is the sensor area, and the inlet area and the sensor area An area a1 that does not face the powder detection means 20 is a storage area in which toner can be stored. Among these areas, the entrance area is set to have a larger area than the sensor area and flows in the toner. Can be prevented from clogging in the entrance area.

  Furthermore, the toner outlet in the inlet region is configured to be continuous with the toner inlet side in the storage region rather than the sensor region, so that the toner introduced into the inlet region is transported to the inlet of the storage region by the transport unit. As a result, toner conveyance is not delayed in the entrance area, and toner clogging in the entrance area can be prevented.

  By setting the areas and setting the transport order between the areas, the amount of toner in the process of moving the toner to each area can be changed in the distance between the weir plates in the transport section and in the moving direction by the partition plates 35 and 36. In the area a4 close to the powder full detection means 34 corresponding to the final stage of the conveyance process at a time before the toner storage box 14 becomes full so as not to be unevenly distributed between the areas. On the other hand, the toner is filled.

  That is, the overall transport flow can be finely controlled by the arrangement patterns of the two types of transport units 33 having different transport directions, and the vicinity of the powder full detection means 34 is filled early, resulting in false detection. Can be prevented.

  The arrangement pattern of each conveyance unit 33 is not limited to this example, and an optimum pattern can be determined by experiments or the like according to conditions such as toner flow characteristics.

  As shown in FIG. 3, support members 40, 40 that support the same side end portion of the stirring plate 26 from the lower surface side are provided near the powder fullness detection means 34 of the lower case 22 (see FIG. 3). 5 is omitted). The function of the support member 40 will be described based on FIG. 6 (a schematic sectional view seen from the cam receiving portion 29 side).

  When the reciprocating motion is performed in a state where the end of the stirring plate 26 on the side away from the eccentric cam 30 is supported by the support member 40, the toner conveyance direction is reversed on both sides with the support member 40 as a boundary.

  That is, the transport unit 33A near the eccentric cam 30 moves so as to scoop up the toner in the container from the bottom to the top (arrow R), and the toner transport direction is the left direction in the figure.

  On the other hand, although the transport unit 33B has the same configuration as the transport unit 33A, the toner moves up from the top to the bottom (arrow L), and the toner transport direction is the right direction in the figure.

  By utilizing this characteristic, the support member 40 is arranged so that a conveying flow is generated in a direction away from the inlet in a portion close to the powder inlet portion 20 and in a direction toward the inlet in a portion far from the inlet. As a transport flow.

  In this embodiment, the toner movement is ensured when moving in the forward path that contributes to toner conveyance by changing the toner movement mode between the forward path and the backward path, and the toner transport is not significantly affected in the backward path. As a configuration of the powder conveying means 24 used as the configuration described above, the configuration shown in FIG. 7 may be used.

  In FIG. 7A, the powder conveying means 24 corresponds to the conveying member (33Fa for the conveying unit 33F exemplified above) in the conveying unit 33 shown in FIG. 3, but in FIG. 24), the dam plate portion is inclined in a direction in which the toner can be pushed and moved while scooping the toner in the forward path. As a result, the amount of toner transport increases in the forward direction of the powder transport unit 24 as compared with the return direction (see FIG. 7B) in which the toner is leveled.

  Moreover, as a structure for giving a function similar to the inclination of the dam plate portion, as shown in FIG. 7C, the dam plate portion is formed in a conical cone shape having a vertical surface facing the forward direction, and in the forward route. It is also possible to adopt a configuration in which the amount of toner transported is larger than that in the return path.

1 is a schematic front view of an image forming apparatus using a powder container according to an embodiment of the present invention as a powder collection container. It is a whole perspective view of a powder collection container. It is a perspective view which shows the conveyance direction in each conveyance part of a powder collection container. It is a schematic sectional drawing which shows the reciprocating motion of a stirring plate. It is a perspective view which shows the whole conveyance flow in a powder collection container. It is a figure explaining the mechanism in which a conveyance direction reverses with a support member as a boundary by reciprocation when a stirring plate is supported by a support member. It is sectional drawing which shows the principal part modification of the conveyance part used for a present Example, respectively. It is an assumption block diagram for obtaining uniform conveyance. It is another assumption block diagram for obtaining uniform conveyance.

Explanation of symbols

DESCRIPTION OF SYMBOLS 14 Toner collection box as powder container 20 Powder inlet part 24 Powder conveyance means 33 Conveyance part 34 Powder fullness detection means as powder detection means

Claims (7)

In the powder container in which the box whose size in the thickness direction perpendicular to this direction is reduced with respect to the vertical and horizontal directions is used ,
A powder inlet provided in the box ;
A powder conveying means for moving the powder introduced from the powder inlet portion toward a powder detection portion for detecting powder fullness provided in the box ;
The powder conveying means is
A stirring member provided with a conveying member configured in parallel with a plurality of barrier plates that are partitioned in a rectangular shape by the ribs that run in the vertical and horizontal directions and have an angle in the vertical and horizontal directions and can move the powder;
An eccentric cam accommodated in a receiving part integrated with the stirring member and capable of moving the stirring member in the reciprocating direction and the height direction;
Means for driving the eccentric cam,
The stirring member supports the lower surface in the thickness direction by a support member disposed near the powder detection unit between the powder inlet and the powder detection unit in the reciprocating motion direction by the eccentric cam. Thus , the powder container is characterized in that the conveying direction of the powder is changed during the reciprocating motion with the support member as a boundary . The powder container according to claim 1, wherein
During the reciprocating motion, the agitating member scoops up the powder from the bottom on one side with the support member as a boundary, scrapes the powder from the top to the bottom on the other side, and contradicts the conveying direction of the powder. Powder container characterized by having a direction . The powder container according to claim 1 or 2,
The stirring member conveys the powder toward the powder detection unit when scooping the powder during the reciprocating motion from the bottom to the top, and leveles the powder when scooping the powder from the top to the bottom. powder container, characterized in that. In the powder container according to claim 1 Symbol placement,
The powder container, wherein the stirring member included in the powder conveying means is inclined in a direction in which the weir plate portion can be pushed and moved while scooping up the toner in the forward path . In the powder container according to claim 1 Symbol placement,
The powder container is characterized in that the stirring member included in the powder conveying means has a conical cone shape in which the weir plate portion has a vertical surface facing the forward path . A toner container using the powder container according to claim 1. An image forming apparatus using the toner container according to claim 6 .

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