TONER CONTAINER AND ELECTROPHOTOGRAPHIC PRINTER USING THE SAME

Abstract: The structure of a toner cartridge used for an electrophotographic printer is detachably attached to the printer. A rotary stirrer member (4) is provided in contact with the inner walls of a cartridge (100) in order to reliably stirr the toner stored in the toner cartridge (100). The rotary stirrer member (4) is rotated by a gear (5) that is rotated by an external driving force.

Description: TECHNICAL FIELD The present invention relates to a toner container and an electrophotographic printer employing the same. BACKGROUND TECHNOLOGY A conventional electrophotographic printer of this type is disclosed in Japanese Utility Model Laid-Open Publication No. 1-97356. This electrophotographic printer has a rotatable cylindrical stirring means in a hopper for containing developer therein (hereinafter referred to as developer hopper) to prevent the so-called toner blocking phenomenon from occurring inside the developer hopper fixed to the electrophotographic The toner blocking phenomenon means that a mass of toner is generated inside the developer hopper. A developer supply roller, which is driven by an external device, is provided at the portion adjacent to the lower end of the developer hopper. The stirring means contacts the developer supply roller so that it is driven by the developer supply roller. However, this electrophotographic printer has a problem in that the effect involving in stirring the toner is relatively remarkably reduced when the developer hopper is formed as a cartridge. There is developed an electrophotographic printer having a detachable toner container as the developer hopper, the so-called toner cartridge which is replaced with another toner cartridge for supply the toner with ease in order to facilitate the supply of the toner or prevent the toner from scattering on the other portion of the electrophotographic printer such as a paper feed system when the toner is supplied into the electrophotographic printer. A replaceable toner cartridge as a replacement unit is now manufactured and sold to be employed by the photographic printer of this type. Since the toner cartridge of this type is filled with toner at the factory when the electrophotographic printer is manufactured, it can not be touched by users' hands in ordinary circumstances. Accordingly, it was a serious problem that the toner cartridge, which is liable to be kept in the warehouse for a long time, is likely to generate the toner blocking. This toner blocking is liable to be caused by the mass of toner which is generated in the toner cartridge during the keeping in the warehouse and sticks to the inner wall of the toner cartridge or all the toner forms a simple large mass. If the toner blocking is generated, the resistance of the mass of toner to the stirring means is generally remarkably increased. In particular, when the mass of toner takes a part of the stirring means thereinto, it sometimes happens that the stirring means can not rotate even if it contacts the supply roller. If the stirring means does not rotate, the toner is not stirred, which causes the anomalous abrasion of the developer. There was another problem in that the user can not take out the mass of the toner after inspecting the inside of the cartridge every time the cartridge is replaced with another one and the frequency of the replacement of the toner increase if the amount of the toner in the toner cartridge is decreased to prevent the toner blocking from generating which causes the increase of the printing cost. US-A-4 739 907 discloses a toner cartridge and an electrophotographic printer with such a toner cartridge according to the preambles of claim 1 and claim 5, respectively. The stirring member of that toner cartridge is comprised of a first coil and a second coil, both of which are disposed along the full lenght of the container. The first coil has a diameter substantially the same as the diameter of the container, and the second coil has a smaller diameter as the first coil and is disposed inside the first coil. The first coil moves toner into a direction of an opening formed at one end of the container, from which the toner is supplied to a developing section. An object of the present invention is that a sufficient amount of toner can always be supplied to the central portion of the printing paper, where much toner is used. With regard to the above mentioned toner cartridge and electrophotographic printer this object is solved by the characterizing features of claims 1 and 5, respectively. The electrophotographic printer is morever capable of mounting the toner cartridge thereon without spoiling the handiness of the cartridge. Since the electrophotographic printer has a space having a cylindrical form therein wherein the toner is stored and a stirring means rotatably provided in the space so as to touch substantially the entire surface of the inner wall forming the space, it is possible to prevent the toner from sticking to the inner wall and stir all the amount of the toner with assurance. Accordingly, it is possible to provide the stable supply of the toner and print uniformly with high accuracy. It is possible to drive the stirring means by a drive means provided in the electrophotographic printer, whereby the stirring means can be driven overcoming a heavy load even if the heavy load is applied to the stirring means by the mass of toner, since a driven means to be connected with the stirring means is provided outside the toner cartridge. Furthermore, it is possible to mesh a drive force transmission means the driven means at the side of the toner cartridge assurance without obstructing the toner cartridge in attaching to or detaching from the electrophotographic printer since the drive force transmission means, which transmits the drive force from the drive means to the drive means provided at the side of the toner cartridge is rotatably provided in the electrophotographic printer accompanied by the attachment and detachment operations of the toner cartridge relative to the electrophotographic printer. Still furthermore, it is possible to obtain a reduction gear mechanism having the small diameter and large reduction gear ratio, as a result, the driving device can be made small, or the single drive means can serve as the drive unit of several parts in common, such as a photo sensitive drum etc., since the reduction gear mechanism is composed of two gears having the same axis of rotation and substantially the same diameter and a gear meshing with both of these gears, which involves the reduction of cost of the parts and the consumption power. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view showing an external appearance of a detachable toner cartridge according to the present invention, Fig. 2 is a perspective view showing an arrangement of a stirring means, Fig. 3 is a cross sectional view taken along the longitudinal direction of a toner cartridge, Fig. 4 is a view explaining a mechanism for fixing the toner cartridge, Fig. 5 is a perspective view showing the state where the toner cartridge is mounted on an electrophotographic printer, Fig. 6 is a perspective exploded view of a drive mechanism, Fig. 7 is a perspective view showing an external appearance of the electrophotographic printer and Fig. 8 is a view explaining a printing process according to the electrophotographic printer. BEST MODE FOR CARRYING OUT THE INVENTION An electrophotographic printer according to an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a perspective view showing an external appearance of a detachable toner storing container (hereinafter referred to as a toner cartridge) according to the embodiment of the present invention. In the same figure, designated at 1 is an outer cylinder, 2 is an inner cylinder, 3a and 3b are end plates, 4 is a stirring member and 5 is a gear. The outer cylinder 1 and the inner cylinder 2 are respectively thin hollow cylindrical members. The outer and inner cylinders 1 and 2 have substantially the same length and the inner cylinder 2 contacts an inner wall of the outer cylinder 1 at the entire length thereof. Both ends of the inner cylinder 2 are closed by the end plates 3a and 3b which are fixed thereto. The end plates 3a and 3b have substantially the same diameter as that of the outer cylinder 1. With such an arrangement, the outer cylinder 1 can rotate relative to the inner cylinder 2 and does not get out of position relative to the inner cylinder 2 since the outer cylinder 1 is restricted to move by the end plate 3a and 3b in the longitudinal direction thereof. The outer cylinder 1 and the inner cylinders 2 have respectively openings 11 and 21 at the side surfaces thereof as shown in fig. 1. Accordingly, it is possible to open or close the openings by relative rotations between the outer cylinder 1 and the inner cylinder 2. The stirring member 4 is inserted inside the inner cylinder 2. The stirring member 4 is formed by machining basically a filamentary member, e.g. a piano wire spirally and connected integrally with the gear 5 by an end member 41 and supported by the inner cylinder 2. When the gear 5 is rotated, the stirring member 4 rotates inside the inner cylinder 2 to form a surface of revolution touching internally the inner cylinder 2. An arrangement of the stirring member 4 is illustrated in Fig. 2. The stirring member 4 comprises the end member 41, a spiral portion 42, a central portion 43 and a spiral portion 44. According to the present invention, the end member 41 is a rectangular metal plate, the spiral portion 2, the central portion 43 and the spiral portion 44 are respectively formed by machining the piano wire. The end member is fixed to the spiral portion 42, the spiral portion 42 fixed to the central portion 43, the central portion 43 fixed to the spiral portion 44 respectively by silver brazing or soldering. The piano wire of the spiral portion 42 is spiralled in the opposite direction to the spiral portion 44 as evident in Fig. 2. Accordingly, if the stirring member 4 rotates in the direction as shown in the arrow A in Fig. 2, the toner, not shown, is collected at the portion about the central portion 43 inside the toner cartridge 100. This generates the effect that a sufficient amount of the toner can be always supplied to the central portion of the printing paper where much toner is used. The gear 5 is fixed to the end member 41. The gear has a central axis, not shown, which is common to axes of the spiral portions 42 and 44. Fig. 3 is a cross sectional view taken along longitudinal direction of the toner cartridge 100 at the portion adjacent to the end plate 3a. In the same figure, designated at 51 is an axis integrated with the gear 5, 52 is a pawl provided at the tip end of the axis 51, 22 is an end surface of the inner cylinder 2, 23 is a round hole defined at the center of the end surface 22, 24 are projections protruding from the end surface 22, 45 is a cut protrusion provided at the end member 41 and 46 is a square hole provided at the end member 41. The axis 51 has a central axis, not shown, which is common to axes of the gear 5 and the spiral portion 42, and penetrates the round hole 23 and is rotatably supported by the inner cylinder 2. The pawl 52 of the axis 51 penetrates the square hole 46 and meshes with the cut protrusion 45. Accordingly, the pawl 52 presses the end member 41 so that the end member 41 is not moved away from the end surface 22. As a result, the gear 5 and the end member 41 clamp the end surface 22, whereby the gear 5 and the stirring member 4 are restricted to move in the direction of the central axes thereof. The pawl 52 has a root touching internally with the square hole 46 in cross section. Hence, the end member 41 is driven by the gear 5 and capable of rotating. Described hereinafter are a mechanism for attaching the toner cartridge 100 to or detaching the same cartridge 100 from a photosensitive drum, described later, and a mechanism for driving the stirring member 4. Fig. 4 is schematic view explaining the mechanism for fixing the toner cartridge 100 to the photosensitive drum cartridge. In the same figure, designated at 31 is a groove defined in the end plate 3a, 32 is a notched portion defined at a part of the periphery of the end plate 3a, and 33 is a pawl defined at a part of the periphery of the end plate 3a. Designated at 6 is a fixing member, 61 is a knob integrated with the fixing member 6, 62 is a guide integrated with the fixing member 6, 63 is an axis integrated with the fixing member 6, 63a is a pawl provided at the tip end of the axis 63 and 64a and 64b are gears integrated with each other and rotatably supported by a shaft which penetrates the fixing member 6, not shown. The shaft supporting these gears 64a and 64b will be described later by illustration. Designated at 7 is a toner cartridge holder integrated with the photosensitive drum cartridge. The toner cartridge holder 7 has a round hole 71 and a substantially circular long hole 72. The toner cartridge holder 7 has also a recess 73 having a semi circular shape in cross section. With such a mechanism, the axis 63 is inserted into the round hole 71 and is rotatable relative to the toner cartridge holder 7 and supported by a mechanism, described later so as not to come out from the round hole 71. At this time, the gear 64a is inserted into the long hole 72 and movable in the long hole 72 as the fixing member 6 rotates. At this state, if the end plate 3a is moved along the fixing member 6 and the toner cartridge 100 is inserted into the recess 73 in the direction of the arrow B, i.e. in the direction from the face of the drawing to the back thereof, the position of the end plate 3a is restricted by the toner cartridge holder 7 so that the gear 64b passes through the notched portion 32 and meshes with the gear 5. At the same time, the guide 62 positioned in parallel with the direction of the arrow B meshes with the groove 31. When the toner cartridge 100 is fixed to the printer, the fixing member 6 is turned at 90 degrees in the direction of the arrow C. The knob 61 is brought into contact with the pawl 33 to thereby drive and turn the end plate 3a. At this time, since the end plate 3a is engaged with the fixing member 6 by way of the groove 31 and the guide 62, the end plate 3a becomes perpendicular relative to the direction of the arrow B together with the guide 62 and the groove 31 when the fixing member 6 is turned. Since the toner cartridge 100 is restricted to move in the direction of the arrow B and the direction perpendicular to the direction of the arrow B by the toner cartridge holder 7, it can not be come out from the toner cartridge holder 7. If the same mechanism is provided at the end plate 3b, the toner cartridge 100 can be fixed to the toner cartridge holder 7. In this case, it is evident that the end plate 3b can dispense with the long hole 71, the gears 64a and 64b and the notched portion 32. Fig. 5 is a perspective view showing the state where the toner cartridge 100 is mounted on a photosensitive drum cartridge 200. In the same figure, designated at 81 is a toner supply roller formed of a sponge and disposed substantially under the toner cartridge 100, 82 is a developing roller formed of rubber and provided in contact with the toner supply roller 81 and 83 is a photosensitive drum provided in contact with the developing roller 82 and having an optical conductive layer at the surface thereof. The photosensitive drum cartridge 200 is formed by incorporating these components with the toner cartridge holder 7. Designated at 12 is a restriction member fixed to the peripheral surface of the outer cylinder 1 and has ends thereof 12a and 12b. If the toner cartridge 100 is inserted into the toner cartridge holder 7 and the pair of fixing members 6 are turned by the operation of the pair of knobs 61, the end plates 3a and 3b engaged with each fixing member 6 are turned. At this time, the inner cylinder 2 fixed to the end plates 3a and 3b at both ends thereof is also turned. Whereas, the outer cylinder 1 can not be substantially turned since the one end 12a of the restriction member 12 is brought into contact with the toner cartridge holder 7 to restrict the turning of the outer cylinder 1. Accordingly, the opening 21 of the inner cylinder 2 is turned and put on the opening 11 of the outer cylinder 1 which is not turned. When two openings 11 and 21 are put one above the other, the toner is supplied to the surface of the toner supply roller 81. The toner supplied from the surface of the toner supply roller 81 is supplied to the surface of the photosensitive drum 83 through the surface of the developing roller 82 and selectively attached on an electrostatic image formed on the optical conductive layer so as to form a toner image which is transferable on the printing paper. Whereupon, when the knob 61 is operated in the direction opposite to the direction wherein the toner cartridge 100 is fixed to the toner cartridge holder 7 so as to remove the toner cartridge 100 from the toner cartridge holder 7, the fixing member 6, the end plates 3a and 3b and the inner cylinder 2 are turned in the direction opposite to the direction wherein in the toner cartridge 100 is fixed. The outer cylinder 1 is restricted to turn since the other end 12b of the restriction member 12 is brought into contact with the toner cartridge holder 7 and resists against the turning of the outer cylinder 1. Accordingly, the opening 21 is moved away from the opening 11 so that the inner cylinder 2 closes the opening 11, thereby closing the toner cartridge 100. When the toner cartridge 100 is fixed to the toner cartridge holder 7, there occurs the case that the knob 61 can not be smoothly turned since the axes between the fixing member 6 and the end plates 3a are not aligned with each other, or the axes of the fixing member 6 and the end plate 3b are not aligned with each other due to the shallow meshing between the gear 64b and the gear 5. This is caused by the fact that the tooth tip and the tooth root of the gear 64 is not precisely opposed with but deviated from those of the gear 5. In such a case, if the toner cartridge 100 is pushed into the toner cartridge holder 7 while the knob 61 is swung little by little utilizing the gear 64b is supported by the fixing member 6, the axes between the fixing member 6 and the end plate 3a or the axes between the fixing member 6 and the end plate 3b are well aligned with each other so that the knob 61 can be smoothly moved. Fig. 6 is an exploded perspective view showing a drive mechanism of the embodiment of the present invention. In the same figure, designated at 8 is a drive shaft rotatably driven by a drive unit, not shown, 9 is a drive gear rotatable together with the drive shaft, 10 is a fixed post fixed to the toner cartridge holder 7, 13 is an idle gear rotatably supported by the fixed post 10, 14 is a a ring gear, 15 is a movable post provided at the ring gear 14, 16 is a planetary gear rotatably supported by the movable post 15, 24 is a fixed gear, 25 is a tube integrated with the fixed gear 24, 26 is a key groove defined at the tip end of the tube 25 at the opposite side of the fixed gear 24, 27 is a key defined in a round hole 71, 28 is a driven gear, 64c is a shaft integrally mounted on a gear 64b and 65 is a round hole defined in the fixing member 6. The driven gear 28 is inserted into the ring gear 14. The tube 25 inserts into the driven gear 28. The tube 25 is fixed to the toner cartridge holder 7. That is, the round hole 71 has two-staged diameter portions, i.e. the large diameter portion and the small diameter portion from the side of the tube 25 and the tube 25 is engaged in the large diameter portion of the round hole 71. At this time, the key groove 26 and the key 27 are engaged with each other whereby the tube 25 and the fixed gear 24 integrated with the tube 25 can not rotate. However, the driven gear 28 and the ring gear 14 can freely rotate. The shaft 63 is inserted into the tube 25. The tube 25 has two-staged diameter portions at the side of the fixed gear 24 as illustrated in Fig. 6 in the same way as the round hole 71. The pawl 63a is engaged with the large diameter portion. As a result the tube 25, the fixed gear 24, the shaft 63, the driven gear 28 and the ring gear 14 are held by the toner cartridge holder 7. These elements can independently rotate except the tube 25 and the fixed gear 24. Fixing member 6 has a circular hole 65 to which a shaft 64c integrated with a gear 64b is inserted. The shaft 64 is fixed to a gear 64a. Accordingly, both the gears 64a and 64b are integrally rotatable. A drive force applied to the drive shaft 8 by a drive unit, not shown, is transmitted to the drive gear 9, the idle gear 13 and the ring gear 14 in this order to thereby rotate the movable post 15. At this time, since the planetary gear 16 meshes with the fixed gear 24, the planetary gear rotates around the fixed gear 24 while rotates on its own axis. The planetary gear 1 also meshes with the driven gear 28. The driven gear compriss a large diameter portion 28a, an annular portion 28b and a small diameter portion 28c. The large diameter portion 28a meshes with the planetary gear 16 and has a pitch diameter substantially same as that of the fixed gear 24 and the teeth which are different from those of the fixed gear 24 in number. With such an arrangement, the fixed gear 24, the planetary gear 16 and the large diameter portion 28a constitute a kind of planetary gear mechanism wherein the driven gear 28 rotates at low speed accompanied by the rotation of the planetary gear 16. The direction of the rotation of the planetary gear 16, i.e. the direction of rotation of the ring gear 14 and the direction of rotation of the driven gear 28 coincide with each other when the large diameter portion 28a has more teeth than the fixed gear 24. On the contrary, when the large diameter portion 28a has less teeth than the fixed gear 24, the direction of rotation of the ring gear 14 is contrary to that of the driven gear 28. According to this embodiment, it may be arbitrarily determined which of the fixed gear 24 and the large diameter portion 28 should have more teeth than the other considering the desirable directions of rotation of the shaft 8 and the gear 5. Fig. 6 shows the state wherein the large diameter portion 28 has more teeth than the fixed gear 24. However, the difference in the number of teeth between the fixed gear 24 and the large diameter portion 28a is preferable to be less in order to rotate the driven gear 28 smoothly. When the driven gear 28 is rotated in the manner as described above, the drive force of rotation is transmitted by way of the gears meshing with each other in the order of the small diameter portion 28c, the gear 64a piercing the long hole 72, the shaft 64c and the gear 64b, whereby the gear 5 which meshes with the gear 64b is rotated. Even if the fixed member 6 is turned on the shaft 63, the arrangement of the gears is kept to mesh with each other, so that the drive force is unchangeably transmitted. This is caused by the fact that the gears 64a and 64b are rotated round the shaft 63 supported by the fixed member 6 accompanied thereby, while the driven gear 28 and the gear 5 meshing with the gear 64b have the same axis in common with the shaft 63. That is, when the fixed member 6 is turned, the gear 64a is rotated round the periphery of the driven gear 28 while the gear 64b is rotated round the periphery of the gear 5 respectively meshing with each other. With such an arrangement of the drive mechanism, many gears have the same axes in common, into the ring gear 14 is inserted the driven gear 28 and inserted into the driven gear is the tube 25, and the gears are arranged at the both sides of the ring gear 14 so that it is possible to construct a drive mechanism making an effective use of a small space. The fixed gear 24 and the driven gear 28 have different angles of rotation per tooth, i.e., the values obtained by dividing 360 degrees by number of teeth. Since each of the angles of rotation per tooth corresponds to that of the planetary gear, a relation motion is generated between the fixed gear 24 and the driven gear 28 accompanied by the rotation of the planetary gear 16. The drive mechanism set forth above makes use of the relative motion as the drive force. As a result, a great speed reduction ratio can be easily obtained with the arrangement of the fixed gear 24 and the driven gear 28 having large numbers of teeth respectively but a little difference therebetween. It results in the advantage that the drive force can be obtained from the photosensitive drum for rotating the drive shaft 8 without applying a large load to the drive mechanism of the photosensitive drum, or the stirring member 4 can be driven with a large torque. The drive mechanism may be constructed so as to directly drive the ring gear 14 or the driven gear 28 by a motor exclusively provided for stirring the toner. The photosensitive drum cartridge 200 loaded with the toner cartridge 100 in this way is mounted on the electrophotographic printer as described later. Fig. 7 is a perspective external view of the electrophotographic printer and Fig. 8 is a view explaining printing process according to the electrophotographic printer. In the same figures, designated at 300 is an electrophotographic printer, having a power switch 301 for starting the electrophotographic printer 300, an operation panel indicating the setting of the printing condition and the error condition of the electrophotographic printer 300, a stacker portion 303 to which the printed sheet is fed. Designated at 311 and 312 are printing sheet cassettes in which the printing sheets are stacked and detachable from the electrophotographic printer 300. The electrophotographic printer 300 has therein feed rollers 321 and 322 for feeding the printing sheets stacked in the printing sheet cassettes 311 and 312, a pair of rollers 323 and 324 for conveying in the photographic printer each printing sheet fed from the printing sheet cassettes 311 and 312, an LED array for emitting a light on the photosensitive drum 83 for thereby forming an electrostatic latent image on the photosensitive drum 83, a transfer electrostatic charger 327 for transferring the toner electrostatically charged on the photosensitive drum 83 on the printing sheet, a pair of heat rollers for fixing the toner transferred on the printing sheet and a photosensitive drum cartridge 200. The photosensitive drum cartridge 200 has an electrostatic charger 84 for electrostatically charging the photosensitive drum 83 uniformly, an electrostatic electricity eliminating light source 85 for uniformly eliminating the electrostatic electricity charged on the photosensitive drum 83 and a cleaner 86 for eliminating the charged toner on the photosensitive drum 83 as well as the toner supply roller 81, the developing roller 82, and the photosensitive drum 83. The printing process of the electrophotographic printer will be described hereinafter. The printing sheet fed from the printing sheet cassette 311 or 312 by the feed roller 321 or 322 are conveyed to the photosensitive drum 83 by way of the roller 322. The photosensitive drum 83 to be rotated by a drive source, not shown, is uniformly electrostatically charged by the electrostatic charger 84 and forms the electrostatic latent image on the surface thereof by the LED array 326. The electrostatic latent image charged on the surface of the photosensitive drum 83 can be visually imaged by the toner supply roller 82 for supplying the toner. The image visually imaged by the toner is transferred to the printing sheet conveyed to the photosensitive drum 83 by the transfer electrostatic charger 327. Thereafter, the static electricity on the surface of the photosensitive drum 83 is uniformly electrostatically eliminated and the toner remained on the surface of the photosensitive drum 83 is cleaned by the cleaner 85 which is brought into contact with the photosensitive drum 83. Thereafter, the next image forming process follows. At this time, since the drive force is applied to the drive shaft 8 accompanied by the rotation of the photosensitive drum 83, the stirring member 4 in the toner cartridge 100 is rotated, thereby stirring the toner uniformly. The image transferred to the printing sheet is fixed on the printing sheet by the heat roller 328 and the printing paper having the image fixed thereon is fed forward and then switched in the conveying direction thereof to the stacker portion 303 or to the arrow A. The printing sheet conveyed to the arrow A is thereafter discharged from the electrophotographic printer 300 to the outside of the electrophotographic printer 300. With the arrangement set forth above, when the toner cartridge 100 is inserted into the toner cartridge holder 7, grooves 31 each provided at the end plates 3a and 3b at both sides of the toner cartridge 100 is engaged in the each guide 32 provided at the fixing member 6. At the same time the gear 64b is engaged with the gear 5. When the knob 61 is operated to rotate the fixing member 6 round the shaft 63, both the end plates 3a and 3b rotate accompanied by the rotation of the fixing member 6. As a result, both the end plates 3a and 3b are respectively fixed by the guide 32 and the toner cartridge holder 7 whereby the whole of the toner cartridge 100 is fixed to the toner cartridge holder. At the same time, the gear 64a rotates round the driven gear 28 and the gear 64 b rotates round the gear 5 respectively meshing with each other accompanied by the rotation of the fixing member 6. At the same time, the inner cylinder 2 fixed by both the end plates 3a and 3b at both ends thereof rotates with both the end plates 3a and 3b. Whereupon, the outer cylinder 1 is neither fixed to the end plate 3a nor to the end plate 3b and the restriction member 12 fixed to the outer peripheral surface of the outer cylinder 1 is brought into contact with the toner cartridge holder 7 at both ends 12a and 12b. Accordingly, the outer cylinder 1 cannot rotate. Consequently, the opening 11 defined on the outer periphery of the outer cylinder 1 and the opening 21 on the outer periphery of the inner cylinder 2 are overlapped with each other at the lower portion of the toner cartridge 100 so that the toner cartridge 100 is open downward whereby the toner can be supplied toward the electrophotographic printer. At this state, if the drive force is applied to the drive shaft 8, the drive force can be transmitted to the ring gear 14 through the drive gear 9 and the idle gear 13, thereby rotating the planetary gear 16. The planetary gear 16 rotates while it meshes with two gears having different numbers of teeth, i.e. the fixed gear 24 and the large diameter portion 28a of the driven gear 28 whereby relative motions between the fixed gear 24 and the large diameter portion 28a is generated. With this relative motion, the gear 5 meshing with the toner cartridge holder 7 is rotated by the fixed gear 24 by way of the tube 25, thereby generating the drive force which is transmitted to the stirring member 4. Since the stirring member 4 touches internally with the internal wall of the substantially cylindrical inner cylinder 2 and has filament members disposed in parallel with the rotary axis of the inner cylinder 2 at the central portion thereof and spiral filament members at both ends thereof, the mass of the toner can be scraped away from the internal wall of the inner cylinder 2 at substantially all positions thereof. Accordingly, the mass of the toner can be prevented from sticking to the inner wall of the inner cylinder 2 of the toner cartridge 100 so that all the amount of the toner is sufficiently stirred and supplied to the electrophotographic printer. A scope of the present invention is not always limited to the embodiment set forth above and can be variously modified without departing therefrom. The embodiment set forth above does not exclude modified embodiments from the scope of the present invention as defined by the appended claims. INDUSTRIAL UTILIZATION The toner container according to the present invention is adapted for the electrophotographic printer employing the LED, laser beam and the like as the light source for forming the electrostatic latent image and for the electrophotographic printer with high printing accuracy, small size and low cost.

Claims: A toner cartridge (100) to be mounted on a photosensitive drum cartridge (200) which is loaded in an electrophotographic printer (300), comprising: a hollow cylindrical container (2) to accommodate a toner employed by the electrophotographic printer; a filamentary stirring member (4) rotatably disposed in the container and touching the inner surface of the container; and means (5) mounted on the container for rotating the stirring member (4) from outside the container so that the stirring member sweeps substantially the entire inner surface of the container; characterized in that the container having an elongated opening (21) disposed in the circumferential surface of the container in an axial direction thereof for discharge of toner at a central portion of the container; and the stirring member (4) having first and second spiral portions (42, 44) which spiral in opposite directions from each other and a central portion (43) having a linear shape disposed between the first and second spiral portions. A toner cartridge according to claim 1, wherein the toner cartridge (100) further comprises an engaging means (3a, 3b) provided at the cartridge side for detachably engaging with the photosensitive drum cartridge (200) to be loaded in the electrophotographic printer (300). A toner cartridge according to claim 1 or claim 2, wherein the filamentary stirring member (4) comprises a steel wire formed of carbon steel. A toner cartridge according to one of the preceding claims, wherein the toner cartridge (100) is comprised of an inner cylinder (2) and an outer cylinder (1). An electrophotographic printer (300) having a photosensitive drum cartridge (200) detachably loaded therein for receiving a toner, the photosensitive drum cartridge mounting a hollow cylindrical toner cartridge (100) which has a space for containing the toner therein, wherein the toner cartridge (100) comprises: a filamentary stirring member (4) rotatably disposed in the toner cartridge and touching the inner surface of the space; a driven means (5) supported by the toner cartridge for rotating the stirring member (4) from outside the toner cartridge so that the stirring member sweeps substantially the entire surface of the container; and a cartridge side engaging means (3a, 3b) for detachably engaging with the photosensitive drum cartridge (200) to be loaded in the electrophotographic printer (300); characterized in that the container having an elongated opening (21) disposed in the circumferential surface of the container in an axial direction thereof for discharge of toner at a central portion of the container, the stirring member (4) having first and second spiral portions (42, 44) which spiral in opposite directions from each other and a central portion (43) having a linear shape disposed between the first and second spiral portions; and the photosensitive drum cartridge (200) comprises: a printer side engaging means (6, 7) for engaging with the cartridge side engaging means (3a, 3b) of the toner cartridge; a drive means comprising a planetary gear mechanism composed of two gears (24, 28a) coaxially mounted on a rotary shaft and having substantially same diameter and a planetary gear (16) capable of generating relative motion in the two gears and an output shaft (28c) rotatable by the relative motion; and a drive force transmission means (64a-c) engaging with the output shaft (28c) and with the driven means (5) supported by the toner cartridge for transmitting the drive force from the drive means to the driven means (5).

Inventors: KIKUCHI HIROSHI, KOGA YOSHITOMO, MATSUDA KIYOSHI, MOMIYAMA YOSHIHARU, NAKAJIMA SHIGEKI, OBARA KAZUKI, ONO HISAO, OTA YUKIO, KIKUCHI, HIROSHI,, KOGA, YOSHITOMO,, MATSUDA, KIYOSHI,, MOMIYAMA, YOSHIHARU,, NAKAJIMA, SHIGEKI,, OBARA, KAZUKI,, ONO, HISAO,, OTA, YUKIO,, KIKUCHI, HIROSHI, OKI ELECTRIC INDUSTRY CO., LTD., KOGA, YOSHITOMO, KI ELECTRIC INDUSTRY CO., LTD., MATSUDA, KIYOSHI, OKI ELECTRIC INDUSTRY CO., LTD., MOMIYAMA, YOSHIHARU, OKI ELECTRIC IND. CO., LTD., NAKAJIMA, SHIGEKI, KI ELECTRIC INDUSTRY CO., LTD., OBARA, KAZUKI, OKI ELECTRIC INDUSTRY CO., LTD., ONO, HISAO, OKI ELECTRIC INDUSTRY CO., LTD., OTA, YUKIO, OKI ELECTRIC INDUSTRY CO., LTD.
Applicants: OKI ELECTRIC IND CO LTD, OKI ELECTRIC INDUSTRY COMPANY, LIMITED
Application year: 1991
Main classification: G03G15
IPC codes: G03G15