JP4055238B2 - Development device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the technical field of developing devices used in image forming apparatuses such as laser printers and laser facsimiles that form images by electrophotographic technology.
[0002]
[Prior art]
Conventionally, in this type of developing device, for example, Japanese Patent Laid-Open No. 3-288875 (known example) is known as a toner storage container that is detachably provided in an electrophotographic printing apparatus.
[0003]
In this known example, a toner storage container having a substantially rotating body is provided with a stirring member 4 having a helical coil shape driven by an outer cylinder 1, an inner cylinder 2 and a gear 5, and both ends of the inner cylinder 2 are provided. The end plates 3a and 3b are detachably supported by the toner cartridge holding portion 7 with the fixing member 6 interposed therebetween, but at least the shaft 63 is engaged with the round hole 71 in the recess 73. Attaching / detaching means such as rotatably supporting the fixing member 6 and engaging the guide 62 with the groove 31 is adopted.
[0004]
[Problems to be solved by the invention]
Although the above-described known examples can be easily replenished with a removable toner cartridge, there is still room for improvement.
[0005]
That is, in the above-mentioned known example, the structure of the attaching / detaching means for the toner storage container is extremely complicated, requiring many steps for the attaching / detaching operation, and the number of components is not small, so there is a risk of failure. In addition to being there, it required skill for maintenance and inspection.
[0006]
A first problem to be solved by the present invention is to provide a toner cartridge that can be locked in a developing cartridge in a predetermined mounting position.
[0007]
A second problem to be solved by the present invention is to provide a toner cartridge that can be easily removed from the mounting position by being urged by an elastic means.
[0008]
A third problem to be solved by the present invention is that operability is good because the toner cartridge can be locked in the developing cartridge by an operation that allows the toner to be supplied by rotating the inner case with a handle. Is to provide things.
[0009]
The fourth problem to be solved by the present invention is that the toner cartridge can be locked in the developing cartridge without providing any special locking means, and the structure is simplified. It is to be.
[0010]
[Means for Solving the Problems]
As means for solving the above-described problems in the present invention, the following means are provided.
[0011]
(1) In a developing device having a developer carrier and a detachable toner cartridge, the toner cartridge is provided with a cylindrical inner / outer case fitted so as to be relatively rotatable, and the inner and outer cases are provided. An agitator gear interlocking with the agitator arranged in the case is provided on the inner case so as to be disengageable from the drive gear, and a handle for turning the inner case and a guide means having an oval cross-sectional shape are fixed on the inner case. and, a receiving means which can engage the guide means on the casing of the developing cart Riddji, wherein the provided agitator gear engageable with the driving gear, thereby receiving hole portion of the receiving means to slide the guide means A first region that can be rotated and a second region that can be rotated, and provided with elastic means for urging the guide means in the direction of the first region in the second region. A developing device characterized in that it can be locked in the receiving hole portion so as not to escape.
[0012]
(2) The receiving hole portion is a linear guide groove having a relatively small width in the first region, and is a circular hole shape larger than the width in the second region. The developing device according to (1).
[0013]
According to the above-mentioned corresponding means, the guide means can be inserted into the receiving means so that the toner cartridge can be securely locked at the required mounting position and can be easily removed. Operation is also easy.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0015]
FIG. 6 is a schematic diagram showing an example of an image forming apparatus 1000 using the developing unit 400 according to the present invention.
[0016]
Hereinafter, the outline of the image forming apparatus 1000 will be described, and then the developing cartridge 410 will be described in detail.
[0017]
The image forming apparatus 1000 is an apparatus that can form a full-color image using a developer using four color developers of yellow, cyan, magenta, and black (hereinafter, toner is used as an example, and hence toner T). is there.
[0018]
In FIG. 6, reference numeral 1100 denotes an outer box of the apparatus. In this outer box 1100, an exposure unit 100, a paper feeding unit 200, a photosensitive cartridge 300, a developing unit 400, an intermediate transfer unit 500, a fixing unit 600 and the like are provided. Yes.
[0019]
The photosensitive cartridge 300 includes a latent image carrier 310, a charging roller 320 as a charging unit that contacts the outer peripheral surface of the latent image carrier 310 and uniformly charges the outer peripheral surface, and a cleaner unit 330. ing.
[0020]
The developing unit 400 includes a developing cartridge 410Y for yellow, a developing cartridge 410C for cyan, a developing cartridge 410M for magenta, and a developing cartridge 410K for black.
[0021]
Each of these developing cartridges 410Y, 410C, 410M, and 410K contains toners of yellow, cyan, magenta, and black, respectively.
[0022]
Further, developer carriers 430Y, 430C, 430M, and 430K are provided, respectively, so that only the developer carrier of any one development cartridge can come into contact with the latent image carrier 310.
[0023]
The intermediate transfer unit 500 includes a medium driving roller 510, a scavenging roller 520, a tension roller 530, a secondary transfer roller 540, an intermediate transfer belt 550 stretched around these rollers, and the intermediate transfer belt 550. And a medium cleaner 560 capable of contacting and separating.
[0024]
A backup roller 570 is disposed opposite to the secondary transfer roller 540.
[0025]
The medium drive roller 510 is rotationally driven by transmission means (not shown) at substantially the same peripheral speed as that of the latent image carrier 310, so that the intermediate transfer belt 550 is circulated and driven at substantially the same peripheral speed as that of the latent image carrier 310. It has come to be.
[0026]
The toner image on the latent image carrier 310 is transferred onto the intermediate transfer belt 550 while the intermediate transfer belt 550 is circulated, and the toner image transferred onto the intermediate transfer belt 550 is transferred to the secondary transfer roller 540. Are transferred to a recording sheet S such as a sheet supplied from the sheet feeding unit 200.
[0027]
The sheet feeding unit 200 includes a tray 210 on which recording sheets S are stacked, a pickup roller 220, and a separation roller 230 that reliably separates the sheets fed by the pickup roller 220 one by one. ing.
[0028]
The recording sheet S fed by the paper feeding unit 200 is supplied between the intermediate transfer belt 550 and the secondary transfer roller 540 by the transport roller 240 and subjected to transfer processing, and is subjected to fixing processing by the fixing unit 600, and the paper transport roller 250. More discharged.
[0029]
The fixing unit 600 includes a fixing roller 610 having a heat source and a pressure roller 620 pressed against the fixing roller 610.
[0030]
The operation of the image forming apparatus 1000 as described above is as follows.
[0031]
(1) When a print command signal (image formation signal) is input from a host computer (not shown), the latent image carrier 310, the developer carrier 430 of the developing unit 400, and the intermediate transfer belt 550 are driven to rotate.
[0032]
(2) The outer peripheral surface of the latent image carrier 310 is uniformly charged by the charging roller 320.
[0033]
{Circle around (3)} The exposure unit 100 exposes the outer peripheral surface of the uniformly charged latent image carrier 310 according to the first color (for example, yellow) image information to form a yellow electrostatic latent image.
[0034]
(4) The developer carrying member 430Y of the developing cartridge 410Y for the first color (for example, yellow) starts to rotate and simultaneously contacts the latent image carrying member 310, whereby the electrostatic latent image is developed, and the first color is developed. A toner image (for example, yellow) is formed on the latent image carrier 310, and the developer carrier 430Y of the development cartridge 410Y for the first color is separated from the latent image carrier 310 and stops rotating.
[0035]
(5) The toner image formed on the latent image carrier 310 is transferred from the latent image carrier 310 onto the intermediate transfer belt 550.
[0036]
(6) The toner remaining on the latent image carrier 310 is removed by the cleaner blade 331 of the cleaner unit 330 and then collected by the waste toner screw 332.
[0037]
(7) The second color, the third color, and the fourth color are repeated according to the contents of the print command signal, and toner images according to the contents of the print command signal are superimposed on the intermediate transfer belt 550. The above operations (2) to (6) are repeated.
[0038]
(8) The recording sheet S is supplied from the paper feeding unit 200 at a predetermined timing, and when the leading edge of the recording sheet S reaches the secondary transfer roller 540, the toner image on the intermediate transfer belt 550 is transferred onto the recording sheet S. .
[0039]
(9) When the recording sheet S passes through the fixing unit 600, the toner image is fixed on the recording sheet S, and the recording sheet S is discharged out of the case 1100 through the paper conveyance roller 250.
[0040]
The outline of the image forming apparatus 1000 has been described above. Next, the developing unit 400 and the developing cartridge 410 will be described.
[0041]
The developing unit 400 includes four developing cartridges 410 (Y, C, M, and K) that are detachably incorporated.
[0042]
Note that an arbitrary developing cartridge 410 in the outer box 1100 can be attached and detached, and the photosensitive member cartridge 300 can also be attached and detached.
[0043]
FIG. 7 is an enlarged view of the development cartridge 410M.
[0044]
The four developing cartridges 410 (Y, C, M, and K) are slightly different in shape and the like, but the basic structure is common, so that the developing cartridge 410M for magenta is represented. An embodiment will be described.
[0045]
The development cartridge 410 includes a case 420, a developer carrier 430 that supplies the toner T stored in the case 420 to the surface of the latent image carrier 310, and a supply that supplies the toner T to the developer carrier 430. A roller 440, an agitator 451, 452 having two transfer fins 461, 462 for transferring toner T toward the supply roller 440, a toner cartridge 470 that can replenish the toner T, and the developer carrier 430. And a thin layering unit 480 that controls the amount of toner on the developer carrier 430.
[0046]
The toner cartridge 470 is detachably attached to the developing cartridge 410. As shown in FIG. 2, the inner and outer cases 472 and 473 fitted with an elastic member 471 so as to be relatively displaceable. A cylindrical shape is provided, and the toner T can be supplied by aligning the openings 474 and 475 of the inner and outer cases 472 and 473.
[0047]
Reference numeral 479 denotes a flange that is locked to the inner case 472 and rotates integrally with the inner case 472, and is disposed at both ends of the inner case 472 in the longitudinal direction.
[0048]
A handle 476 protrudes from the flange 479 and turns the inner case 472 with respect to the outer case 473.
[0049]
In addition, the toner cartridge 470 is formed in a cylindrical shape by integrally forming two-divided members, and the agitator 477 is supported by a shaft hole 479A provided at the center of a flange 479 that closes both sides of the inner case 472. Thus, the agitator gear 477G can be turned by a driving means disposed on the developing cartridge side.
[0050]
Further, the transverse shape of the guide means GU projecting outward at the position of the shaft hole 479A of the flange 479 is non-circular as shown in FIG. 3, and is preferably substantially oval with parallel straight line portions GU1 and arc portions GU2. It is configured.
[0051]
Next, as shown in FIG. 3, a receiving means RE is provided at the tail portion of the side wall 423 of the case 420 of the developing cartridge 410 to which the toner cartridge 470 is detachably attached.
[0052]
The receiving means RE is provided with a disk-like support portion RE1 that supports both sides of the flange 479 of the toner cartridge 470, and the support portion RE1 has a receiving hole that is recessed in an inclined manner in the radial direction thereof. Department RE2 is established.
[0053]
The shape of the receiving hole part RE2 is composed of an open guide groove RE4 forming a first region and a circular hole RE3 at the center position forming a second region following this, and in particular, this guide groove RE4. Is an oblique straight line, and is preferably oriented so as to be opened to a position above the circular hole RE3.
[0054]
Further, regarding the dimensions of each part, the width D1 of the parallel straight portion GU1 and the curvature R1 of the arc portion GU2 of the guide means GU are respectively set so that the guide means GU can move smoothly without rattling in the receiving means RE. The dimension is slightly smaller than the width D2 of the guide groove RE4 of the RE and the curvature R2 of the circular hole RE3, and is larger than the width D2.
[0055]
A spring receiving portion RE5 is recessed in the bottom of the circular hole RE3, and an inner end portion of an elastic body RE6 such as a coil spring is inserted into the spring receiving portion RE5 so that the outer end is inserted into the circular hole RE3. Preferably, the elastic body RE6 extends and contracts in the longitudinal direction of the guide groove RE4.
[0056]
Reference numeral 477 denotes an agitator, which is provided with fins 478, which prevents the toner T from coagulating and supports its supply.
[0057]
The developer carrier 430 is rotatably supported by the case 420, and a supply roller 440 that is parallel to the developer carrier 430 and whose surfaces are in pressure contact with each other is also rotatably supported by the case 420. .
[0058]
The toner T thinning means 480 is supported in a cantilever manner on the receiving member 481, and the blade 482 is brought into contact with the developer carrier 430.
[0059]
The case 420 is provided with a toner tank 424 in a substantially semi-cylindrical row, and is held in a wedge-shaped space formed by sliding the fins 461 and 462 of the rotating agitators 451 and 452 in sliding contact with the inner surface 424a of the toner tank 424. In this way, the toner T is transferred.
[0060]
The fins 461 and 462 are formed in a thin plate shape having flexibility, and when the toner tank 421 is suddenly displaced and released in the vicinity of the supply roller 440, the toner T is transferred so as to be held in the wedge-shaped space. The toner is transferred to the surface of the supply roller by a mechanical conveying force so as to be repelled by a restoring force due to elasticity of 461 and 462.
[0061]
The rotational loads of the agitators 451, 452, and 477 are made uniform by differentiating their rotational phases. When n toner transfer means are connected in series (n = 3 in this case), n transfer means. By shifting the angles of the fins 461, 462, and 478 by 360 ° / n, the sliding contact lengths of the fins 461, 462, and 478 rotating in contact with the inner surface 421a are substantially constant regardless of the angles of the agitators 451, 452, and 477. And
[0062]
Since the load fluctuations before and after the toner T is bounced by the agitators 451, 452, and 477 are dispersed, even in a high density toner having poor fluidity, the loads by the agitators 451, 452, and 477 are equalized, and the torque fluctuations of the apparatus are reduced. It can be reduced.
[0063]
The case 420 is detachably attached on the mounting table 1200.
[0064]
As shown in FIGS. 8 to 10, the drive gear 710 in the drive means of the agitator gear 477G provided on the developing cartridge 410 side is engaged with the agitator gear 477G of the toner cartridge 470 so as to be detachably engaged with the agitator 477. The agitator 477 is swiveled only when the guide means GU of the toner cartridge 470 is disposed at the center position of the receiving means RE of the developing cartridge case 420 and the drive gear 710 is engaged with the agitator gear 477G. Thus, the toner T can be carried out (see FIGS. 5, 7, and 10).
[0065]
Therefore, in order to attach the toner cartridge 470 to the developing cartridge 410, the toner cartridge 470 is disposed as shown in FIG. 3, and the guide means GU is inserted into the receiving hole portion RE2 provided in the support portion RE1 of the receiving means RE. The guide member GU is inserted in the direction indicated by the arrow A, and the elastic member RE6 is compressed by the guide member GU so as to enter the spring receiving portion RE4. This guide member GU forms the second region of the receiving member RE. The state arrives at the position of the circular hole RE3 opened at the center position (see FIG. 4).
[0066]
This state corresponds to a predetermined mounting position of the toner cartridge 470, and the curvature R1 of the guide means GU is larger than the width D2 of the guide groove RE4 forming the first region of the receiving means RE. The guide means GU can turn only at.
[0067]
Therefore, when the handle 476 is turned in the direction of the arrow B (see FIG. 4), the flange 479 and the inner case 472 integrally attached to the flange 479 are turned in the outer case 473 by the handle 476 and the respective openings 474 are opened. 475 are aligned so that the toner T in the inner case 472 can be supplied, and the curvature R1 of the arc portion GU2 of the guide means GU is larger than the width D2 of the guide groove RE4, so that the guide means GU is received. The toner cartridge 470 is locked in a non-removable manner in the means RE, and at the same time, the entire toner cartridge 470 is locked at a predetermined mounting position in a state where the toner T can be supplied in the developing cartridge 410.
[0068]
Therefore, for example, when the toner cartridge 470 has not reached the predetermined mounting position shown in FIG. 5, the guide means GU cannot turn, and as a result, the opening 474 of the inner case 472 of the toner cartridge. Since the toner T is not aligned with the opening 475 of the outer case 473, the toner T cannot be supplied, and the occurrence of toner leakage can be prevented.
[0069]
Further, since the agitator gear 477G of the toner cartridge 470 is not connected to the driving means of the agitator gear 477G disposed in the developing cartridge 410, the agitator gear 477G or its driving means is mounted by incomplete toner cartridge mounting. Is not inadvertently destroyed.
[0070]
In addition, when the toner cartridge 470 is replaced, the replacement is performed by the reverse operation procedure described above, but the handle 476 is turned in the direction of arrow B ′ shown in FIG. 5 to reach the position shown in FIG. When the parallel linear portion GU1 of the guide means GU is aligned with the guide groove RE4, the guide means GU is pushed out toward the guide groove RE4 in the direction of arrow A ′ in FIG. 3 by the repulsive force of the elastic body RE6. The toner cartridge 470 can be removed.
[0071]
In the developing cartridge 410 configured as described above, the toner cartridge 470 is loaded, the inner case 472 is turned by the handle 476 to align the openings 474 and 475, and the agitator 477 is turned by the agitator 477 that turns the toner T. The toner is transferred in the directions 452 and 451 and supplied onto the developer carrier 430 through a supply roller 440 that is driven to rotate, and is attached to the latent image carrier 310.
[0072]
Similarly, the development cartridge 410 as described above is detachably attached to the outer box 1100 in a total of four as yellow 410Y, cyan 410C, magenta 410M, and black 410K. Since the function is the same as that of the above-described magenta 410M, repeated description is omitted.
[0073]
【The invention's effect】
The specific effects of the present invention described above are as follows.
[0074]
(1) The toner cartridge can be securely mounted at a predetermined mounting position in the developing cartridge.
[0075]
(2) The toner cartridge can be easily detached from the developing cartridge.
[0076]
(3) The operability of attaching / detaching the toner cartridge is good.
[0077]
(4) The structure of the toner cartridge loading / unloading means is simple.
[0078]
(5) To prevent damage to the drive means of the toner cartridge.
[Brief description of the drawings]
FIG. 1 is an enlarged cross-sectional view of a main part of a toner cartridge according to an embodiment of the present invention.
FIG. 2 is an assembly diagram of the toner cartridge in FIG.
FIG. 3 is an explanatory diagram illustrating how the toner cartridge in FIG. 1 is attached.
4 is an explanatory diagram of the next mounting process of FIG. 3;
FIG. 5 is an explanatory diagram of the next mounting process of FIG. 4;
6 shows the agitator driving means in FIG. 1, and is an explanatory view of the state of FIG.
7 is an explanatory view showing a state in the middle of mounting in FIG.
8 is an explanatory diagram of the state of FIG. 4 in FIG.
FIG. 9 is a schematic view of an image forming apparatus equipped with the developing cartridge of the present invention.
FIG. 10 is an enlarged view of a developing cartridge according to the present invention.
[Explanation of symbols]
410 Developing cartridge 420 Case 470 Toner cartridge 472 Inner case 476 Handle GU Guide means RE Receiving means RE4 First region (guide groove)
RE3 Second region (circular hole)
RE6 Elastic means (body)

Claims (2)

In a developing device including a developer carrying member and a detachable toner cartridge, the toner cartridge is provided with a cylindrical inner / outer case fitted so as to be relatively rotatable, and the inner case is provided in the inner case. An agitator gear interlocking with the agitator arranged is provided on the inner case so as to be disengageable from the drive gear, and a handle for turning the inner case and a guide means having an oval cross-sectional shape are fixedly provided on the inner case for development. a receiving means which can engage the guide means on the casing cart Riddji, provided the agitator gear engageable with the driving gear, the receiving hole of the receiving means can slide the guide means 1 And a second region that can be rotated. In the second region, there is provided elastic means for urging the guide means in the direction of the first region. A developing device according to claim escape incapable it has be retained in serial receiving hole.   The receiving hole portion is a linear guide groove having a relatively small width in the first region, and has a circular hole shape larger than the width in the second region. The developing device according to 1.

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