JP3939892B2 - Developing device with toner cartridge - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a developing device for developing an electrostatic latent image into a toner image, which is used in an electrostatic image forming machine such as an electrostatic printer, a copying machine, and a facsimile. The present invention relates to a developing device in which a toner cartridge for supplying toner to a developing chamber is detachably mounted in a housing.
[0002]
[Prior art]
As is well known to those skilled in the art, in an electrostatic image forming apparatus, as a developing device for developing an electrostatic latent image into a toner image, a housing having a developing chamber for defining a circulation path of the developer, and a developer A developer agitating / conveying means disposed in the developing chamber for conveying through the circulation path while stirring; and a developer applying means for applying the developer in the developing chamber to the electrostatic latent image to be developed. Such a developing device is widely used in practice. In a typical example of such a developing apparatus, the circulation path defined in the developing chamber is formed by connecting at least two linear paths extending in parallel and adjacent ends of the linear paths. And both ends connected. The developer stirring / conveying means is composed of rotating spiral blades disposed in each of the linear paths in the circulation path. By rotating the rotating spiral blade in a predetermined direction, the developer in the developing chamber is conveyed through the circulation path while being stirred. The developer applying means is formed of a developing roller extending along one of the linear paths in the circulation path. The developing roller is driven to rotate in a required direction, and the developer in the developing chamber is held on its peripheral surface and is carried to the developing area, where toner is applied to the electrostatic latent image in the developing area. The developer accommodated in the developing chamber is a so-called one-component developer made of only toner or a so-called two-component developer containing carrier particles together with toner.
[0003]
In the developing device of the above-described form, the toner is consumed as the development is performed. Therefore, it is necessary to appropriately replenish the toner in the developing chamber. Therefore, normally, a toner cartridge is detachably attached to the housing, and toner is supplied from the toner cartridge to the developing chamber. The toner cartridge includes a cartridge case containing toner. A toner discharge opening is formed in the lower wall of the cartridge case. On the other hand, a toner receiving opening is formed in the developing chamber, and when the toner cartridge is mounted at a predetermined position of the housing, the toner discharge opening of the cartridge case is positioned above the toner receiving opening of the developing chamber. In the cartridge case, toner conveying means is provided for conveying the toner in the cartridge case toward the toner discharge opening and discharging the toner through the toner discharge opening. The toner conveying means is drivably coupled to a dedicated drive source such as an electric motor disposed in the housing or cartridge case. When the toner in the developing chamber is reduced, which can be detected by an appropriate toner amount detecting means, the toner conveying means is driven, and in accordance with this, the toner in the cartridge case is discharged from the toner discharge opening, and receives the toner. It is introduced into the developing chamber through the opening. When the toner in the cartridge case is exhausted, the toner cartridge is replaced with a new toner cartridge. A developing chamber shutter that selectively closes the toner receiving opening of the developing chamber and a cartridge shutter that selectively closes the toner discharge opening of the cartridge case are provided to remove the toner cartridge from the housing. The toner receiving opening is closed by the developing chamber shutter, and the toner discharging opening is closed by the cartridge shutter.
[0004]
[Problems to be solved by the invention]
Thus, in the conventional developing device of the above-described form, in order to replenish the toner appropriately from the toner cartridge according to the consumption of the toner in the developing chamber, a dedicated drive for driving the toner conveying means in the toner cartridge There is a problem to be solved that requires a source and is hindered from sufficiently reducing manufacturing costs due to this.
[0008]
  The present invention has been made in view of the above facts, and itsmainThe technical problem is that a dedicated drive source for driving the toner conveying means in the toner cartridge is not required, and therefore the manufacturing cost can be sufficiently reduced, but the toner in the developing chamber can be reduced. It is another object of the present invention to provide a new and improved developing device capable of appropriately supplying toner from a toner cartridge to a developing chamber.
[0011]
[Means for Solving the Problems]
  In the present inventionAccording to the above mainIn order to achieve the technical problem, the developer agitating / conveying means for conveying the developer along the circulation path defined in the developing chamber while stirring the developer has a toner receiving opening disposed above it. It is reduced locally in the toner receiving area. As a result, developer stagnation is generated in the toner receiving area, and the stagnation amount of the developer fluctuates according to the toner amount in the developing chamber. The replenishment of toner from the toner cartridge to the developing chamber is automatically controlled according to the amount of developer staying in the toner receiving area, and thus according to the amount of toner in the developing chamber.
[0012]
  That is, according to the present invention, the abovemainAs a developing device to achieve technical problems, the developer circulation pathIs formedA housing having a developing chamber and the circulation path while stirring the developer;alongDeveloper agitating and conveying means disposed in the developing chamber for conveying;A drive source for driving the developer stirring and conveying means;A developer applying means for applying the developer in the developing chamber to an electrostatic latent image to be developed; and a toner cartridge detachably mounted in the housing for replenishing toner in the developing chamber. And
  The developing chamber is formed with a toner receiving opening located above the toner receiving area in the circulation path.
  The toner cartridge isA cartridge case in which a toner discharge opening located above and opposite the toner receiving opening is formed when the toner cartridge is mounted in the housing; and the toner contained in the cartridge case Toner conveying means for conveying toward the discharge opening,
  The conveying ability of the developer agitating and conveying means is locally reduced on the downstream side of the toner receiving area,
  When the toner cartridge is mounted on the housing, the toner conveying means of the toner cartridge is drivingly connected to the driving source for driving the developer stirring and conveying means.
  A developing device is provided.
[0013]
  In a preferred embodiment, the developer agitating / conveying means is composed of a rotating spiral blade extending along the circulation path, and the outer diameter of the spiral blade is locally reduced on the downstream side of the toner receiving area. And / or the helical blade pitch is locally reduced downstream of the toner receiving area.The TheThe developer applying means can also be drivingly connected to the driving source.An upper surface wall is disposed on the upper surface of the developing chamber, an immersion area is formed on the upper wall, and the toner receiving opening is conveniently formed in the immersion area of the upper surface wall. is there. It is preferable that the cartridge case of the toner cartridge has a lower surface wall in which a protruding area having a shape corresponding to the immersion area of the upper surface wall is formed, and the toner discharge opening is formed in the protruding area. . Preferably, a developing chamber shutter movable along the upper surface of the upper surface wall between a closed position covering the toner receiving opening and an open position exposing the toner receiving opening, and the developing chamber shutter closed. Elastic biasing means that is elastically biased to a position is disposed, a contact means is formed on the developing chamber shutter, and a contact means is formed on the cartridge case of the toner cartridge. When the toner cartridge is mounted on the housing, the contact means acts on the contacted means to move the developing chamber shutter to the open position against the elastic biasing action of the elastic biasing means. When the toner cartridge is detached from the housing, the developing chamber shutter is moved to the closed position by the elastic biasing action of the elastic biasing means. The toner cartridge is provided with a cartridge shutter movably mounted between a closed position for closing the toner discharge opening and an open position for opening the toner discharge opening. The housing has a first position and a first position. An operation lever movable between the second position and the toner shutter in a state where the operation lever is positioned at the first position and the cartridge shutter is positioned at the closed position. When the cartridge is mounted on the housing, the field where the cartridge shutter is connected to the operation lever and the cartridge shutter is moved to the open position by moving the operation lever to the second position is preferable. Preferably, the housing is provided with locking means movable between a locked position and an unlocked position, and elastic biasing means for elastically biasing the locking means to the locked position, and the toner The cartridge case of the cartridge is provided with a means to be locked, the contact means is formed on the lock means, the contact means is formed on the lock means, and the housing When the toner cartridge is mounted, the corresponding contact means acts on the contacted means to move the lock means toward the unlocked position against the elastic biasing action of the elastic biasing means, When the toner cartridge is mounted on the housing, the corresponding contact means passes through the non-contact means, whereby the lock means is moved to the lock position by the elastic biasing action of the elastic biasing means. And acting on the locked means to prevent detachment of the toner cartridge, and further, when the operating lever is positioned at the first position, resists the elastic biasing action of the elastic biasing means. It is allowed to manually move the locking means to the unlocked position, but when the operating lever is moved to the second position, the locking means is resisted against the elastic biasing action of the elastic biasing means. Moving to the unlocked position is prevented.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a preferred embodiment of a developing device constructed according to the present invention will be described in more detail with reference to the accompanying drawings.
[0021]
1 to 3 show a preferred embodiment of a developing device constructed according to the present invention. The developing device shown as a whole by reference numeral 2 includes a developing device main body 4 and a toner cartridge 6.
[0022]
  The developing device main body 4 includes a housing 8, and the housing 8 includes a housing main body 10 and an upper surface wall member 12 attached to the housing main body 10. Development in which the upper surface (more specifically, the main part excluding the left edge) and the left side surface are open in the left half of the housing body 10 which can be molded from an appropriate synthetic resin in FIGS. A chamber 14 is defined. The housing body 10 has a bottom wall 16, side walls 18 and 20, and a connecting wall 22. The connecting wall 22 extends between the upper edges of the left and right side walls 18 and 20 in FIGS. 2 and 3. The bottom wall 16 of the housing body 10 includes three arcuate portions 16a, 16b, and 16c that are arranged in parallel and have a circular cross-sectional shape. An upright wall 24 extending substantially vertically upward is formed between the arc-shaped portion 16 a and the arc-shaped portion 16 b, and straight paths 26 a and 26 b are defined on both sides of the upright wall 24. As clearly understood by referring to FIG. 4 in conjunction with FIG. 1, both ends of the upright wall 24 are separated from the inner surfaces of the side walls 18 and 20 of the housing body 10, and both ends of the upright wall 24 and the side walls 18 and 20 are separated. There is a required gap between the inner surface of the substrate. Accordingly, the two linear paths 26a and 26b extending in parallel with each other are communicated with each other at both ends, and thus extend along one linear path 26a, and then one end of the linear path 26a. One end of the other straight path 26b from the first section, extends along the straight path 26b, andotherFrom the end of the straight path 26aotherAn endless circulation path following the end is defined (developer is circulated through the circulation path as will be further described later).
[0023]
  In the circulation path described above, a developer stirring and conveying means 28 is provided for transporting the developer through the circulation path while stirring the developer. The developer stirring and conveying means 28 in the illustrated embodiment includes a first rotating spiral blade member 30a and a second rotating spiral blade member 30b. The first rotating spiral blade member 30a that can be molded from an appropriate synthetic resin has a central shaft portion 32a and a spiral blade 34a. Similarly, the second spiral blade member 30b that can be molded from an appropriate synthetic resin also has a central shaft portion 32b and a spiral blade 34b. The first rotating spiral blade member 30a is rotatably mounted between the side walls 18 and 20 of the housing body 10 and extends linearly along the linear path 26a. The second rotating spiral blade member 30b is also rotatably mounted between the side walls 18 and 20 of the housing body 10, and extends linearly along the straight path 26b. One end portion (right end portion in FIG. 4) of the center shaft portion 32a of the first rotating spiral blade member 30a and one end portion (right end portion in FIG. 4) of the center shaft portion 32b of the second rotating spiral blade member 30b are the side walls 20. And an input gear (not shown) is fixed to these protruding ends. The side wall 20 has a cover member36The input gear is covered with the cover member 36. A cutout (not shown) is formed in the side wall 20, and an L-shaped partition piece 38 (FIG. 4) is attached to the inner surface of the side wall 20. The central shaft portion 32 a of the first rotating spiral blade member 30 a extends through the partition piece 38 and further extends through the main portion of the side wall 20. A transmission gear 40 (FIG. 4) mounted rotatably is positioned in the notch. The lower half of the transmission gear 40 is exposed downward from the housing body 10 through the notch, and the transmission gear40The inner upper half of the housing is exposed in the housing body 10 between the partition piece 38 and the side wall 20. When the developing device 2 is mounted at a predetermined position of the image forming machine, a drive source 42 (see FIG. 5) may be an electric motor via another transmission gear (not shown) meshed with the lower half of the transmission gear 40. 4) is drivingly connected to the transmission gear 40. The transmission gear 40 is meshed with an input gear (not shown) of the first rotating spiral blade member 30a, and the input gear of the first rotating spiral blade member 30a is connected via a transmission gear (not shown). The second rotating spiral blade member 30b is meshed with an input gear (not shown). Therefore, when the drive source 42 is energized, the first rotating spiral blade member 30a and the second rotating spiral blade member 30b rotate at substantially the same rotational speed in the direction indicated by the arrow 44 in FIGS. Driven. A seal member 46a that is brought into close contact with the inner surface of the partition piece 38 is attached to the right end portion of the central shaft portion 32a of the first rotating spiral blade member 30a in FIG. A seal member 46b that is in close contact with the inner surface of the side wall 20 is attached to the right end of the central shaft portion 32b of the second rotating spiral blade member 30b in FIG.
[0024]
As clearly understood by referring to FIG. 4, the spiral blade 34 a of the first rotating spiral blade member 30 a and the spiral blade 34 b of the second rotating spiral blade member 30 b are set in opposite so-called spiral directions. When the first spiral blade member 30a is rotated in the direction indicated by the arrow 44, the developer is conveyed in the direction indicated by the arrow 48 through the linear path 26a, and the second rotary spiral blade member 30b is rotated by the arrow 44. The developer is transported in the direction indicated by the arrow 48 through the straight path 26b. As clearly understood by referring to FIG. 4, in the illustrated embodiment, the pitch P <b> 2 of the spiral blade 34 a is the other portion in the specific region indicated by the number 50 in the first rotating spiral blade member 30 a. And the outer diameter D2 of the spiral blade 34a is made smaller than the outer diameter D1 in the other part, and the developer agitating and conveying means 28 in the specific region 50 is smaller than the pitch P1. The carrying capacity is reduced locally. The pitch and outer diameter of the spiral blades 34a and 34b in the portion other than the specific region 50 of the first rotating spiral blade member 30a and the entire second rotating spiral blade member 30b are set to be substantially the same. The conveying ability of the agent stirring and conveying means 28 in the area other than the specific area 50 is substantially the same. In order to reduce the conveyance capacity locally in the specific region 50, instead of reducing the pitch and outer diameter of the spiral blade, for example, only the pitch of the spiral blade is set small, and only the outer diameter of the spiral blade is reduced. Setting, forming a notch in the spiral blade, or omitting the spiral blade. The specific area 50 in which the conveyance capability is locally reduced is a toner receiving area in which toner is introduced into the developing chamber 14 through a toner receiving opening 52 (shown by a two-dot chain line in FIG. 4) which will be described in detail later. It is important to be downstream of the region. The effect obtained by locally reducing the conveyance capability in the specific area 50 will be described in detail later.
[0025]
Referring mainly to FIG. 3, developer application means 54 is disposed above the arcuate portion 16 c of the bottom wall 6 in the housing body 10. The developer applying means 54 includes a developing sleeve 56 that is rotatably mounted between the side walls 18 and 20 of the housing body 10. A stationary permanent magnet (not shown) is disposed in the developing sleeve 56. One end portion of the rotating shaft 58 to which the developing sleeve 56 is fixed protrudes through the side wall 20, and an input gear (not shown) is fixed to the protruding end. This input gear is meshed with the input gear of the second rotating spiral blade member 30b. Therefore, when the drive source 42 is energized, the developing sleeve 56 is rotated in the direction indicated by the arrow 44. In association with the developing sleeve 56, a panning means 60 is disposed. As will be further described later, the developing chamber 14 contains a one-component developer composed only of toner (or a two-component developer composed of toner and carrier particles), and the developer is rotated in the direction indicated by the arrow 44. The first rotating spiral blade member 30a and the second rotating spiral blade member 30b are transported through the transport path. The developer applying means 54 holds the developer on the peripheral surface of the developing sleeve 56 that is rotated in the direction indicated by the arrow 44, and conveys the developer through the developing area 62. The ear cutting means 58 regulates the layer thickness of the developer held on the peripheral surface of the developing sleeve 56 and conveyed to the developing area 62. In the developing area 62, the toner in the developer is applied to the electrostatic latent image to be developed, and the electrostatic latent image is thus developed into a toner image.
[0026]
  Referring to FIGS. 5 a and 5 b together with FIG. 1, an operation lever 64 and a connecting member 66 are mounted on the side wall 18 of the housing body 10. The operation lever 64 is shown in FIGS.aBetween the first position shown in FIG. 5 and the second position shown in FIG. 5b. The connecting member 66 is also mounted rotatably between a first position shown in FIGS. 1 and 5a and a second position shown in FIG. 5b. The operation lever 64 is formed with an arm 68 projecting upward, and an engagement tooth 70 that exists over an angular range of approximately 90 degrees is formed on the outer peripheral surface thereof. On the other hand, a fan-shaped protrusion is formed on the outer surface of the connecting member 66, and meshing teeth 72 that exist over an angle range of approximately 90 degrees are formed on the upper surface of the protrusion. The meshing teeth 72 are meshed with the meshing teeth 70 of the operation lever 64. Therefore, when a finger is put on the arm 68 of the operation lever 64 and the operation lever 64 is rotated from the first position to the second position, the connecting member 66 is moved from the first position to the second position. When the operating lever 64 is rotated from the second position to the first position, the connecting member 66 is moved from the second position to the first position.oneIt is rotated to the position. A substantially U-shaped receiving recess 74 is formed on the inner surface of the connecting member 66. The receiving recess 74 is formed with a locking protrusion 76 extending upward from the arcuate bottom surface. Further, a locking projection 78 is also formed on the connecting member 66. The operation of the receiving recess 74, the locking protrusion 76, and the locking protrusion 78 will be described later.
[0027]
Continuing the description with reference to FIGS. 1 to 3, the upper wall member 12 is attached to the housing body 10. The upper wall member 12 has an upper wall 80 that covers the upper surface of the developing chamber 14. An elongated immersion area 82 extending in the width direction (direction perpendicular to the paper surface in FIGS. 2 and 3) is formed in the upper surface wall 80. The cross-sectional shape of the immersion area 82 is an arc shape. In the immersion area 82, a toner receiving opening 52, which may be rectangular, is formed. As can be understood by referring to FIGS. 2 and 3, the top wall member 12 has an upright wall 84 that extends to the left of the immersion area 82 along the immersion area 82 in FIGS. 2 and 3. A pair of support rods 86 projecting substantially horizontally are formed on the upright wall 84 at intervals in the width direction (the direction perpendicular to FIGS. 2 and 3). Only one of the support rods 86 is shown).
[0028]
A developing chamber shutter 88 is attached to the upper wall member 12. The developing chamber shutter 88 has a flat shutter wall 90. A pair of protrusions 92 are formed on the upper surface of the shutter wall 90. An inclined surface 94 constituting the contacted means is formed at the tip of each protrusion 92. Each of the protrusions 92 also includes an extending portion that extends rearward (leftward in FIGS. 2 and 3) from the inclined surface 94. As understood from FIGS. 2 and 3, the extending portion has a hollow prism shape. The shutter wall 90 is further formed with a pair of protrusions 98 protruding forward from both ends thereof. Such a developing chamber shutter 88 is mounted on the upper surface wall member 12 so as to be movable along the upper surface of the upper surface wall 80 between a closed position illustrated in FIG. 2 and an open position illustrated in FIG. In order to elastically bias the developing chamber shutter 88 to the closed position between each of the pair of support rods 86 on the upper surface wall member 12 and each of the extending portions of the pair of protrusions 92 on the developing chamber shutter 88. The elastic biasing means 100, which may be a compression coil spring, is interposed. When the upper wall member 12 is mounted on the housing body 10 and the developing chamber shutter 88 is mounted on the upper wall member 12, the developing chamber shutter 88 is closed as shown in FIG. When positioned, the tips of the pair of protrusions 98 of the developing chamber shutter 88 are brought into contact with the upright wall 102 (FIGS. 2 and 4) formed on the housing body 10, and thus the developing chamber shutter 88 is illustrated. 2 is prevented from moving to the right beyond the closed position. When the developing chamber shutter 88 is positioned at the closed position, the shutter wall 90 covers the toner receiving opening 52 formed in the upper wall member 12 as clearly shown in FIG. Since the toner receiving opening 52 is formed in the immersion area 82 in the upper surface wall 80 of the upper surface wall member 12, a slight gap is formed between the toner receiving opening 52 and the shutter wall 90 due to the presence of the immersion area 82. It should be noted that 104 exists. The function of the gap 104 will be further described later. When the toner cartridge 6 is also attached to the housing body 10, the toner cartridge 6 acts on the inclined surface 94 of the developing chamber shutter 88 and the developing chamber shutter 88 is elastically biased by the elastic biasing means 100 as will be described in detail later. Against the open position shown in FIG. When the developing chamber shutter 88 is moved to the open position, the shutter wall 90 is retracted from above the toner receiving opening 52, and the toner receiving opening 52 is exposed.
[0029]
As shown in FIG. 1, an upright wall 106 protruding upward is formed at one end edge of the upper surface wall 80 of the upper surface wall member 12, and a guide groove 108 extending downward from the upper end of the upright wall 106 is formed. Has been. The upper wall 80 is further provided with a storage wall 110 extending in the width direction. A lock means 112 is stored in the storage wall 110. 5A and 5B together with FIGS. 1 to 3, the locking means 112 has a main portion 114 that is elongated in the width direction (direction perpendicular to the paper surface in FIGS. 1 and 2). The main portion 114 is formed with an operation arm 116 protruding upward. A pair of locking grooves 118 are formed in the main portion 114 at intervals in the length direction. Each of the lock grooves 118 is substantially L-shaped, and an upper edge of the lock groove 118 is defined by the inclined surface 120. As clearly shown in FIGS. 5 a and 5 b, a locking piece 122 that protrudes perpendicularly to the main portion 114 is formed at one end of the locking means 112. Two protrusions 113 are formed on the inner surface of the locking piece 122. Such a locking means 112 is attached to the storage wall 110 so as to be movable between a locked position shown in FIGS. 1 and 5a and an unlocked position shown in FIG. 5b. Between the storage wall 110 and the other end of the locking means 112, an elastic biasing means 124 (FIGS. 5a and 5b), which may be a compression coil spring, is arranged to elastically bias the locking means 112 to the locked position. It is installed.
[0030]
6 and 7 together with FIGS. 1 to 3, the toner cartridge 6 in the illustrated embodiment includes a cartridge case 126. The cartridge case 126 includes a box-shaped case main body 128 having an open upper surface and a lid 130 fixed to the case main body 128 by an appropriate means such as ultrasonic welding. The bottom wall of the case main body 128 has two arc-shaped portions 132a and 132b whose cross-sectional shape is an arc shape. The radius of curvature of the arc-shaped portion 132a is relatively large, and the radius of curvature of the arc-shaped portion 132b is relatively small. As can be understood by referring to FIG. 6, the arcuate portion 132 b is provided with a projecting region 134 projecting downward. The cross-sectional shape of the protruding region 134 is also arc-shaped and concentric with the non-projecting region. The length in the width direction and the radius of curvature of the protruding area 134 are made to correspond to the axial length and the radius of curvature of the immersion area 82 defined in the upper surface wall 80 of the upper surface wall member 12 described above. The protruding area 134 is formed with a toner discharge opening 136 which may be rectangular. As will be described in detail later, when the toner cartridge 6 is mounted in the housing 8 as required, the protruding area 134 of the case main body 128 faces the immersion area 82 defined in the upper surface wall 80 of the upper surface wall member 12. Is positioned, and the toner discharge opening 136 is positioned in the toner receiving opening 52. In order to avoid the so-called blocking of toner in the vicinity of the toner discharge opening 136 and / or the toner receiving opening 52, the width and length of the toner discharging opening 136 are substantially equal to the width and length of the toner receiving opening 52. Preferably they are the same or somewhat smaller than these.
[0031]
  As shown in FIGS. 6 and 7, the case main body 128 has both side walls 138 and 140. A circular opening 150 is formed in the side wall 138, and the toner is filled into the cartridge case 126 through the opening 150. After the cartridge case 126 is filled with toner, a closing member 152 is fixed to the opening 150 to close the opening 150. 7 and FIG. 7 together with FIG. 2 and FIG. 3, between the side walls 138 and 140 of the case main body 128, the toner conveying means 154 extending along the arcuate portion 132a and the arcuate portion 132b. And a toner conveying means 156 extending. The toner conveying means 154 includes a rotation support shaft 158 that is rotatably mounted between the side walls 130 and 140, and a plurality of rectangular conveyance pieces 160 fixed to the rotation support shaft 158. Each of the conveyance pieces 160 can be formed from an appropriate synthetic resin film or sheet. One end portion of the rotation support shaft 158 protrudes through the side wall 140, and an input gear 162 (FIGS. 1 and 6) is fixed to the one end portion. Toner conveying means156Is composed of a rotating spiral blade member having a central shaft portion 164 and a spiral blade 166. One end portion of the central shaft portion 164 protrudes through the side wall 140,TakeAn input gear 168 (FIGS. 1 and 6) is fixed to one end. The input gear 168 is meshed with the input gear 162. When the toner cartridge 6 is mounted on the housing 8 as required, the input gear 162 is engaged with the transmission gear 40 mounted on one side of the housing body 10. Therefore, when the drive source 42 described above is energized, the first rotating spiral blade member 30a, the second rotating spiral blade member 30b, and the developing sleeve 56 disposed in the developing chamber 14 as described above are moved to the arrow 44. In addition to the rotation in the direction indicated by, the toner conveying means 154 and 156 of the toner cartridge 6 are also rotated in the direction indicated by the arrow 170 in FIG. By rotating the toner conveying means 154 in the direction indicated by the arrow 170, the toner present on the arc-shaped portion 132a is conveyed onto the arc-shaped portion 132b by the action of the conveying piece 160, and the toner conveying means 156 is directed in the direction indicated by the arrow 170. , The toner on the arcuate portion 132b is conveyed toward the toner discharge opening 136. It should be noted that in the illustrated embodiment constructed in accordance with the present invention, no dedicated drive source is required to rotate the toner transport means 154 and 156 of the toner cartridge 6.
[0032]
  7 and 8 together with FIGS. 2 and 3, a cartridge shutter 172 is disposed in the cartridge case 126. As clearly shown in FIG. 8, the cartridge shutter 172 includes a shutter member 174 and a connecting member 176. The shutter member 174 has both end portions 178 and 180 having a cylindrical shape..Two flanges 182 having substantially triangular protrusions are formed on one end 178. The main portion 184 of the shutter member 174 has an arc shape whose cross-sectional shape extends over an angle range of approximately 200 degrees. The main portion 184 of the shutter member 174 is formed with a toner passage opening 186 that may be rectangular. The size of the toner passage opening 186 may be substantially the same as that of the toner discharge opening 136 formed in the case main body 128. A seal member 188, which may have a rectangular shape extending along the toner passage opening 186, is attached to the outer peripheral surface of the main portion 184 of the shutter member 174. Conveniently, the size of the sealing member 188 (FIG. 2), which can be formed from a flexible material such as sponge, is somewhat larger than the toner discharge opening 136. One end portion of the connecting member 176 has a relatively small diameter, and a plurality of locking pieces 190 are formed on the outer peripheral surface thereof. A locking groove 192 extending in a diameter shape is formed at the other end of the connecting member 176. As can be understood by referring to FIG. 7, the shutter member 174 is disposed in the above-described protruding area 134 in the arc-shaped portion 132 b of the case main body 128, and the toner conveying means 156 extends through both end portions of the shutter member 174. . One end of the connecting member 176 is inserted into one end 178 of the shutter member 174 through a through hole formed in the side wall 138 of the case main body 128. A locking piece (not shown) corresponding to the locking piece 190 of the connecting member 176 is formed in one end portion 178 of the shutter member 174, and the connecting member 176 is provided in the one end portion 178 of the shutter member 174. When one end is inserted, the locking piece 190 of the connecting member 176 and the locking piece of the shutter member 174 are elastically deformed and connected to each other, and thus the connecting member 176 is fixed to the shutter member 174. The The other end of the connecting member 176, that is, the end where the locking groove 192 is formed protrudes outward from the side wall 138 of the case main body 128.
[0033]
As clearly shown in FIG. 6, a pair of locked means 194 is disposed on the rear wall of the case main body 128 (the wall located on the left side in FIGS. 2 and 3) with an interval in the width direction. Each of the locked means 194 has a hook shape and has an inclined surface 196 and a horizontal surface 198.
[0034]
As clearly shown in FIG. 3, the toner cartridge 6 is detachably attached to the housing 8 of the developing device body 4. When the toner cartridge 6 is mounted at a predetermined position of the housing 8, as can be understood by comparing FIGS. 2 and 3, the protruding region 134 in the arcuate portion 132 b of the bottom wall of the case main body 128 has the housing 8. 2 is in contact with an inclined surface 94 formed on the pair of protrusions 92 of the developing chamber shutter 88 (the inclined surface 94 constitutes a contacted means as described above), and the developing chamber shutter 88 is closed as shown in FIG. 3 is moved to the open position shown in FIG. 3, and thus the toner receiving opening 52 of the developing chamber 14 is exposed. Therefore, the protruding area 134 in the toner cartridge 6 constitutes a contact means that acts on the inclined surface 94 of the developing chamber shutter 88.
[0035]
As is understood by referring to FIG. 6 together with FIG. 5, when the toner cartridge 6 is mounted on the housing 8 of the developing device body 4, each of the inclined surfaces 196 of the pair of locked means 194 of the toner cartridge 6 is Acting on the inclined surfaces 120 of the pair of locking grooves 118 formed in the locking means 112 of the housing 8, the locking means 112 is moved from the locked position shown in FIG. 5a to the unlocked position shown in FIG. 5b. When the toner cartridge 6 is mounted at a predetermined position, the inclined surface 196 of the locked means 194 passes through the inclined surface 120 of the locking means 194, so that the locking means 194 is shown in FIG. 5a by the elastic biasing action of the elastic biasing means 124. Return to the locked position. As a result, the horizontal surface 198 of the locked means 194 is caused to enter the deepest portion of the lock groove 118 of the locking means 112, thereby locking the toner cartridge 6 at the required mounting position.
[0036]
When the toner cartridge 6 is mounted in the housing 8 of the developing device main body 4, the cartridge shutter 172 in the toner cartridge 6 is positioned at the closed position shown in FIG. 2, and the seal member 188 discharges the toner from the toner cartridge 6. The toner discharge opening 136 is closed so as to cover the opening 136. When the toner cartridge 6 is mounted in the housing 8 in such a state, the other end of the connecting member 174 in the cartridge shutter 172, that is, the end where the locking groove 192 is formed is the one end edge of the upper wall member 12 in the housing 8. It is guided and lowered by the guide groove 108 of the upright wall 106 formed in the upper wall 106, and enters the receiving recess 74 of the connecting member 66 disposed at one end of the housing body 10. Then, the locking protrusion 76 formed in the receiving recess 74 of the connecting member 66 is inserted into the locking groove 192 formed in the connecting member 174 of the cartridge shutter 172. When the operation lever 64 is rotated from the position shown in FIG. 5 a to the position shown in FIG. 5 b after the toner cartridge 6 is mounted at the required position in the housing 8, the rotation of the operation lever 64 is connected to the cartridge shutter 172 via the connecting member 66. The cartridge shutter 172 is rotated from the closed position shown in FIG. 2 to the open position shown in FIG. When the cartridge shutter 172 is rotated to the open position, the toner passage opening 186 is aligned with the toner discharge opening 136, and thus the toner discharge opening 136 is opened. Therefore, the toner in the cartridge case 126 is supplied into the developing chamber 14 through the toner passage opening 186, the toner discharge opening 136 and the toner receiving opening 52. Such toner supply will be further described later.
[0037]
When the operating lever 64 is rotated to the position shown in FIG. 5 b, the locking protrusions 78 formed on the connecting member 174 are inside the two protrusions 113 of the locking piece 122 formed at one end of the locking means 112. This prevents the locking means 112 from moving from the locked position to the unlocked position. When the operation lever 64 is rotated to the position shown in FIG. 5a (therefore, the cartridge shutter 172 is rotated to the closed position and the toner discharge opening 136 is closed), the locking projection 78 is separated from the locking piece 122, and thus the locking means. The toner cartridge 6 can be detached from the developing device main body 4 by moving 112 to the unlocked position.
[0038]
In the developing device shown in the form as described above, the developing chamber 14 is filled with a so-called one-component developer composed of only toner (or a so-called two-component developer composed of toner and carrier particles). When the development is performed, the toner is applied to the electrostatic latent image by the developer applying unit 54, and thus the toner is consumed as the development is performed. Therefore, it is important to appropriately replenish the toner in the developing chamber 14 according to the consumption of the toner. Thus, as will be clearly understood from the embodiments to be described later, in the illustrated developing device configured according to the present invention, the toner conveying means 154 and 156 disposed in the toner cartridge 6 are provided as necessary. Replenishment of toner from the toner cartridge 6 to the developing chamber 14 is appropriately controlled without requiring a dedicated drive source for selective rotation. More specifically, in the illustrated developing apparatus constructed according to the present invention, the drive source 42 is energized to perform the development, and the developer applying and conveying means 28 (ie, the first rotation). When the spiral blade member 30a and the second rotating spiral blade member 30b) are rotated, the toner conveying means 154 and 156 of the toner cartridge 6 are also connected to the drive source 42, so that the toner conveying means 154 and 156 of the toner cartridge 6 are connected. Accordingly, the toner is conveyed toward the toner discharge opening 136 in the cartridge case 126. On the other hand, in the developing chamber 14, the conveying capacity of the first rotating spiral blade member 30 a constituting the developer agitating and conveying means 28 is such that the toner receiving that allows the toner to be introduced into the developing chamber 14 through the toner receiving opening 52 as described above. The specific area 50 located downstream of the area is locally reduced. Therefore, the developer stays in the upstream of the specific area 50, that is, in the toner receiving area. The retention of the developer prevents the toner from entering the developing chamber 14 through the toner receiving opening 52. The amount of the developer staying in the toner receiving area varies depending on the amount of developer in the developing chamber 14 and thus the amount of toner in the developer. Accordingly, the degree of suppression of the toner entering the developing chamber 14 is varied depending on the amount of toner in the developer in the developing chamber 14, and when the toner amount is reduced, the introduction of toner into the developing chamber 14 increases, and the toner As the amount increases, the introduction of toner into the developing chamber 14 decreases. Thus, the replenishment of toner to the developing chamber 14 is appropriately controlled without directly depending on the drive control of the toner conveying means 154 and 156 of the toner cartridge 6.
[0039]
When the toner in the cartridge case 126 is exhausted, it is necessary to replace the toner cartridge 6. In this case, first, the operation lever 64 is rotated from the position shown in FIG. 5B to the position shown in FIG. 5A. As a result, the cartridge shutter 172 is rotated to the closed position, and the toner discharge opening 136 of the cartridge case 126 is closed. Further, the locking projection 78 formed on the connecting member 174 is retracted from the locking piece 122 of the locking means 112. Accordingly, the lock unit 112 can be moved from the locked position to the unlocked position, the toner cartridge 6 can be unlocked, and the toner cartridge 6 can be detached from the housing 4. Unless the operation lever 64 is rotated to the position shown in FIG. 5a, and therefore the toner discharge opening 136 is not closed by rotating the cartridge shutter 172 to the closed position, the toner cartridge 6 cannot be detached from the housing 4. Therefore, it is reliably prevented that the toner cartridge 6 is detached from the housing 4 without accidentally closing the toner discharge opening 136 and the toner is scattered from the toner discharge opening 1366 to the surroundings.
[0040]
When the toner cartridge 6 is detached from the housing 4, the developing chamber shutter 88 is returned from the open position shown in FIG. 3 to the closed position shown in FIG. 2 by the elastic biasing action of the elastic biasing means 100. The receiving opening 52 is covered with the developing chamber shutter 88. As clearly understood from FIGS. 2 and 3, the toner receiving opening 52 is formed in the immersion area 82 of the upper surface wall 80, and some gap is formed between the toner receiving opening 52 and the developing chamber shutter 88. 104 exists. Therefore, when the developing chamber shutter 88 is moved to the closed position, even if some toner overflows on the upper surface wall 80 in the vicinity of the toner receiving opening 52, the developing chamber shutter 88 is in contact with such toner. And the toner is covered by the developing chamber shutter 88 without being scattered around. After the toner cartridge 6 is detached from the housing 4, the new toner cartridge 6 is mounted on the housing 4 according to the procedure described above, and the operation lever 64 is rotated from the position shown in FIG. 5a to the position shown in FIG. 5b. The cartridge shutter 88 is rotated to the open position, and the toner discharge opening 136 is opened. Thus, it becomes possible to replenish the toner appropriately from the new toner cartridge 6 into the developing chamber 14.
[0041]
Example
A developing device having a configuration as shown in FIGS. 1 to 8 is created, and the developing device is a laser printer having substantially the same configuration as a printer sold by Kyocera Corporation under the trade name “FS-1700”. Equipped to carry out electrostatic latent image development. In the developed developing device, the outer diameter D1 of the spiral blades outside the specific region in the first rotating spiral blade member is 18 mm, the spiral pitch P1 is 20 mm, and the outer diameter D2 of the spiral blades in the specific region is 10 mm. The pitch P2 was 10 mm. The outer diameter D1 of the spiral blade in the second rotating spiral blade was 18 mm, and the pitch P1 was 20 mm. Before the start of development, the developer in the developing chamber was set to substantially zero g, and the variation in the amount of developer in the developing chamber over the course of the development performance time was measured, as shown in FIG. The change in the developer amount in the developing chamber was measured as follows. First, the weight SW of the developing device was measured with the toner cartridge detached. Each time the development of the electrostatic latent image was continued for 10 minutes, the developing device was removed from the printer, and the weight AW of the developing device was measured with the toner cartridge removed from the developing device. The developer increase amount in FIG. 9 indicates the value of AW-SW. From FIG. 9, at the beginning of development, the amount of developer increases to a predetermined amount as the toner flows from the toner cartridge into the developing chamber, but the developer amount is stably maintained at a constant value after a predetermined time has elapsed. In other words, it is understood that the toner is appropriately replenished from the toner cartridge in accordance with the consumption of the toner by performing the development.
[0042]
Comparative Example 1
For comparison, there is no specific region in the first rotating spiral blade member, that is, the spiral blade of the first rotating spiral blade member is uniform throughout, the outer diameter D1 of the spiral blade is 10 mm, and the pitch In the same conditions as in the example except that P1 was 10 mm, the outer diameter D1 of the spiral blade in the second rotating spiral blade member was 10 mm, and the pitch P1 was 10 mm, When the change in the developer amount in the developing chamber over time was measured, it was as shown in FIG. It is understood that the developer amount is not maintained at a constant value and gradually increases as the development is performed.
[0043]
Comparative Example 2
For comparison, there is no specific area in the first rotating spiral blade member, that is, the spiral blade of the first rotating spiral blade member is uniform throughout, the outer diameter D1 of the spiral blade is 18 mm, and the pitch In the same conditions as in the example except that P1 was 10 mm, the outer diameter D1 of the spiral blade in the second rotating spiral blade member was 18 mm, and the pitch P1 was 10 mm, When the change in the developer amount in the developing chamber over time was measured, it was as shown in FIG. As in Comparative Example 1, it is understood that the developer amount is not maintained at a constant value and gradually increases as the development is performed.
[0044]
【The invention's effect】
In the developing device of the present invention, a dedicated drive source for driving the toner conveying means in the toner cartridge is not required, and thus the manufacturing cost can be sufficiently reduced. According to the decrease, the toner can be appropriately replenished from the toner cartridge to the developing chamber.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing a preferred embodiment of a developing device constructed according to the present invention.
FIG. 2 is an exploded cross-sectional view of the developing device shown in FIG.
FIG. 3 is a cross-sectional view of the developing device shown in FIG.
4 is a plan view of a developing device main body in the developing device shown in FIG. 1. FIG.
5A is a perspective view showing the operating lever, the connecting member, and the locking means in the developing device shown in FIG. 1, with the operating lever and the connecting member being in the first position, and FIG. The perspective view which shows the operation lever in the developing device shown, a connection member, and a locking means in the state which has an operation lever and a connection member in a 2nd position.
6 is a perspective view of a toner cartridge in the developing device shown in FIG.
7 is a cross-sectional view of a toner cartridge in the developing device shown in FIG.
8 is a perspective view of a cartridge shutter provided in a toner cartridge in the developing device shown in FIG.
FIG. 9 is a diagram showing changes in development performance time and developer amount in Examples and Comparative Examples 1 and 2;
[Explanation of symbols]
2: Developing device
4: Development device body
6: Toner cartridge
8: Housing
10: Housing body
12: Upper wall member
14: Development chamber
28: Developer stirring and conveying means
30a: first rotating spiral blade member
30b: second rotating spiral blade member
34a: Spiral feather
34b: Spiral feather
42: Driving source
50: Specific area
52: Toner receiving opening
54: Developer application means
64: Operation lever
66: Connecting member
78: Locking protrusion
80: Top wall
82: Immersion area
88: Developing chamber shutter
90: Shutter wall
94: Inclined surface (contacted means)
100: Elastic biasing means
104: gap
112: Locking means
122: Locking piece
124: Elastic biasing means
126: Cartridge case
134: Protrusion area
136: Toner discharge opening
154: Toner conveying means
156: Toner conveying means
172: Cartridge shutter
174: Shutter member
176: connecting member
194: Locked means

Claims (9)

A housing having a developer chamber in which circulation path of the developer is formed, for conveying along the circular path while stirring the developer, a developer stirring and conveying means disposed in the developing chamber, said A driving source for driving the developer agitating and conveying means, a developer applying means for applying the developer in the developing chamber to an electrostatic latent image to be developed, and for supplying toner into the developing chamber; A toner cartridge detachably mounted on the housing,
The developing chamber is formed with a toner receiving opening located above the toner receiving area in the circulation path.
The toner cartridge is accommodated in the cartridge case having a toner discharge opening positioned above and facing the toner receiving opening when the toner cartridge is mounted in the housing. Toner conveying means for conveying toner toward the toner discharge opening,
The conveying ability of the developer agitating and conveying means is locally reduced on the downstream side of the toner receiving area,
When the toner cartridge is mounted on the housing, the toner conveying means of the toner cartridge is drivingly connected to the driving source for driving the developer stirring and conveying means.
A developing device.   The developer agitating / conveying means includes a rotating spiral blade extending along the circulation path, and an outer diameter of the spiral blade is locally reduced on a downstream side of the toner receiving region. The developing device according to 1. The developer stirring and conveying means is composed of a rotary helical blade extending along the circulating path, downstream of said toner receiving region helical blade pitch is caused to locally reduce claim 1 or 2. The developing device according to 2 . Also developing agent application means is drivingly connected to the drive source, the developing device according to any of claims 1 to 3. An upper surface wall is disposed on the upper surface of the developing chamber, an immersion area is formed in the upper surface wall, and the toner receiving opening is formed in the immersion area of the upper surface wall. 5. The developing device according to any one of items 4 to 4 . The cartridge case of the toner cartridge has a lower wall in which a protruding area having a shape corresponding to the immersion area of the upper wall is formed, and the toner discharge opening is formed in the protruding area. 5. The developing device according to 5 . A developing chamber shutter movable along the upper surface of the upper surface wall between a closed position that covers the toner receiving opening and an open position that exposes the toner receiving opening, and the developing chamber shutter is elastically moved to the closed position. Elastic biasing means biased to the toner cartridge, contacted means is formed on the developing chamber shutter, contact means is formed on the cartridge case of the toner cartridge, and the housing When the toner cartridge is mounted, the contact means acts on the contacted means to move the developing chamber shutter to the open position against the elastic biasing action of the elastic biasing means. 7. The developing device according to claim 6 , wherein when the toner cartridge is released, the developing chamber shutter is moved to the closed position by an elastic biasing action of the elastic biasing means. The toner cartridge is provided with a cartridge shutter movably mounted between a closed position for closing the toner discharge opening and an open position for opening the toner discharge opening. The housing has a first position and a first position. An operation lever movable between the second position and the toner shutter in a state where the operation lever is positioned at the first position and the cartridge shutter is positioned at the closed position. When the cartridge is mounted to the housing, the cartridge shutter is coupled to the operating lever, the cartridge shutter is accused moved to the open position by for moving the operating lever to said second position, of claims 1 to 7 The developing device according to any one of the above. The housing is provided with locking means that can move between a locked position and an unlocked position, and elastic biasing means that elastically biases the locking means to the locked position. The cartridge case is provided with means to be locked, the contact means is formed on the lock means, the contact means is formed on the lock means, and the toner is placed on the housing. When the cartridge is mounted, the corresponding contact means acts on the contacted means to move the locking means toward the unlocked position against the elastic biasing action of the elastic biasing means, and the housing is moved to the housing. When the toner cartridge is mounted, the corresponding contact means passes through the non-contact means, whereby the lock means is moved to the lock position by the elastic biasing action of the elastic biasing means, and the It acts on the click means to prevent detachment of the toner cartridge, and further, when the operating lever is brought position to said first position is manually said against the resilient urging action of the elastic biasing means The locking means is allowed to move to the unlocked position, but when the operating lever is moved to the second position, the locking means is moved to the unlocked position against the elastic biasing action of the elastic biasing means. The developing device according to claim 8 , wherein movement is prevented.

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