JP4779472B2 - Developing device, process cartridge, and image forming apparatus - Google Patents

Description

  The present invention relates to a developing device, a process cartridge including the developing device, and an image forming apparatus, and more particularly, to a developing device including a toner replenishing chamber for replenishing toner to a developer storage chamber.

  In an image forming apparatus using an electrophotographic technique such as an electrophotographic copying machine or a laser printer, a developing device for developing an electrostatic latent image formed on a photosensitive member is mounted. Some developing devices include a toner replenishing unit that replenishes toner to the developer storage chamber.

  A developing device including a toner replenishing unit is provided with a developer agitating / conveying member (auger) for agitating and mixing the toner and the carrier in a developer accommodating chamber for accommodating the developer (toner and carrier). ing. Then, the toner is supplied from a toner replenishing unit provided above the developer storage chamber so as to be stirred by the auger (see Patent Document 1).

  By the way, since the specific gravity of the toner is small with respect to the carrier, as in Patent Document 1, when a certain amount or more of toner is supplied from above the developer storage chamber, the toner floats on the carrier. For this reason, even if the auger is used to mix the toner and the carrier, the mixing is not performed sufficiently, and the toner concentration in the developer becomes non-uniform or it takes time until the toner concentration in the developer becomes uniform. There is a problem that it takes.

  Therefore, a toner storage portion of the toner replenishment unit is arranged beside the developer storage chamber, a toner supply port is formed in a partition wall that partitions the toner storage portion and the developer storage chamber, and the lower end of the toner supply port is connected to the developer. Some are supplied in the lateral direction so that the toner enters the developer by being positioned below the surface of the developer contained in the accommodation chamber. That is, in order to prevent the toner from floating in the developer, the toner is supplied from below the surface of the developer.

  In this configuration, the toner storage portion is a partition plate provided between the developer storage chamber and a partition plate provided between the toner supply chamber that stores toner and supplies toner to the toner storage portion. It is a tunnel structure. The toner is supplied from the toner supply port to the developer accommodating chamber while being conveyed through the toner accommodating portion by an auger provided in the toner accommodating portion. At this time, since the toner is conveyed while being compressed by the auger in the toner accommodating portion, a toner lump is generated in the toner accommodating portion. In particular, when a large amount of toner is continuously supplied while rotating the auger at a high speed, such a phenomenon appears remarkably. In addition, the toner may stay in the vicinity of the toner supply port and be compressed, and a toner lump having a large toner supply port may be generated.

  When a lump of toner (toner lump) is supplied to the developer storage chamber, it becomes difficult to uniformly enter the toner between the pitches of the auger blades provided in the developer storage chamber. The toner cannot be mixed uniformly. Further, when the toner lump is large, it is difficult to supply the toner from the toner supply port to the developer storage chamber.

Further, when a large amount of toner is supplied, the toner pressure is increased at the toner supply port because the toner is successively supplied to the toner supply port by the rotation of the auger. At this time, the toner avoids the developer flow and is supplied upward in the flow. As a result, the toner is not mixed in the developer and remains on the top of the developer or on the wall near the toner supply port, so that the toner can be supplied into the developer at a predetermined speed. As a result, the toner supply becomes non-uniform.
JP 2001-305861 A

  An object of the present invention is to supply toner to the developer storage chamber without forming a lump of toner even if the toner is supplied in the lateral direction, and to uniformly mix the toner in the developer.

The present invention described in claim 1 includes a developer containing chamber in which a developer composed of toner and a carrier is accommodated, and the developer is conveyed to the developer carrying member while the toner and the carrier are mixed and agitated by the developer agitating and conveying member. A toner replenishing chamber that accommodates toner to be supplied to the developer accommodating chamber; a dispense chamber that is provided between the toner replenishing chamber and the developer accommodating chamber and that replenishes toner in the toner replenishing chamber; A toner supply port formed on a wall of the dispensing chamber on the developer storage chamber side, a part of which is provided below the surface position of the developer stored in the developer storage chamber, and provided in the dispense chamber. in the developing device having a toner conveying member for supplying to the developer-accommodating chamber supplied toner from the toner supply port from the toner supply chamber, the toner conveying member is rotated to Consists of auger having a spiral blade provided around the shaft, wherein the toner supply opening neighborhood consists of a projection provided at a position opposed to said toner supply opening of the shaft, the developer containing The present invention is characterized in that toner supplied to the chamber or pulverizing means for pulverizing the supplied toner is provided.

  According to the first aspect of the present invention, for example, toner is conveyed in the dispensing chamber by the toner conveying member, and the lump of toner (toner lump) is pulverized by the pulverizing means provided near the toner supply port. The pulverized toner is supplied from the toner supply port to the developer storage chamber.

  In this way, by pulverizing the blocky toner and supplying it to the developer storage chamber, it becomes easier for the toner to enter the developer transported in the developer storage chamber, so a large amount of toner can be continuously supplied. However, the toner does not float above the developer and the toner lump does not remain in the developer. As a result, the agitation of the toner supplied to the developer storage chamber is improved, and the toner is mixed in the developer in a uniform state.

  In addition, the toner near the toner supply port may be agglomerated due to the mutual adhesion force. Even in this case, the agglomerated toner is pulverized by the crushing means near the toner supply port. The toner lump can be prevented from entering.

The toner conveying member is composed of an auger having a rotating shaft and a spiral blade provided on the shaft, and a projecting shape is formed at a position facing the toner supply port of the shaft. A grinding means is provided. When the massive toner is conveyed to the portion constituted by the protrusions, the massive toner is pulverized by the protrusions. The pulverized toner is supplied from the toner supply port to the developer storage chamber.

The present invention according to claim 2 is characterized in that the protrusion is a plate piece provided along the axial direction of the shaft.

According to invention of Claim 2 , the plate is provided in the axis | shaft along the axial direction. Thereby, when the plate piece is rotated by the rotation of the auger, the plate piece comes into contact with the toner over a wide area, so that the toner can be pulverized efficiently.

The present invention according to claim 3 is characterized in that the protrusion is a spiral plate provided in parallel with the blade.

According to the invention described in claim 3 , the shaft is provided with the spiral plate in parallel with the blade. Thus, the spiral plate pulverizes the toner by rotating the auger.

According to a fourth aspect of the present invention, there is provided a developer containing chamber in which a developer composed of toner and a carrier is accommodated, and the developer is conveyed to the developer carrying member while the toner and the carrier are mixed and agitated by the developer agitating and conveying member. A toner replenishing chamber that accommodates toner to be supplied to the developer accommodating chamber; a dispense chamber that is provided between the toner replenishing chamber and the developer accommodating chamber and that replenishes toner in the toner replenishing chamber; A toner supply port formed on a wall of the dispensing chamber on the developer storage chamber side, a part of which is provided below the surface position of the developer stored in the developer storage chamber, and provided in the dispense chamber. A toner conveying member that supplies the toner supplied from the toner replenishing chamber to the developer containing chamber from the toner supply port, and the toner conveying member rotates. It consists of auger having a spiral blade provided around the shaft, wherein the toner supply opening neighborhood, the pitch of the blades of the auger, not opposed to the toner supply opening at a position opposed to the toner supply opening It is constituted by making it different so as to be smaller or larger than the position, and is characterized in that a pulverizing means for pulverizing the toner supplied to the developer storage chamber or the supplied toner is provided.

According to the fourth aspect of the present invention, the pitch of the auger blades at the position facing the toner supply port is different from that of the other part (the position not facing the toner supply port), so that the space between the auger blades is different. The toner (toner lump having the pitch width of the blades) conveyed while being packed is pulverized by the blades at the toner supply port.

  For example, when the blade pitch is made smaller at the position facing the toner supply port than at the other positions, the toner mass conveyed to the position facing the toner supply port is crushed and made fine by the blade.

  Further, when the pitch of the blades is made larger at the position facing the toner supply port than at other positions, the toner lump conveyed to the position facing the toner supply port is crushed while moving between the blade and the blade. Is done. In other words, since the distance between the blades is larger than the size of the toner mass, a gap is generated around the toner mass in the axial direction, and the degree of freedom of movement of the toner mass increases rapidly. While moving in the direction, the adhesion force between the toners is weakened and the toner tends to be crushed.

According to a fifth aspect of the present invention, there is provided a developer containing chamber in which a developer composed of toner and a carrier is accommodated, and the developer is conveyed to the developer carrying member while the toner and the carrier are mixed and agitated by the developer agitating and conveying member. A toner replenishing chamber that accommodates toner to be supplied to the developer accommodating chamber; a dispense chamber that is provided between the toner replenishing chamber and the developer accommodating chamber and that replenishes toner in the toner replenishing chamber; A toner supply port formed on a wall of the dispensing chamber on the developer storage chamber side, a part of which is provided below the surface position of the developer stored in the developer storage chamber, and provided in the dispense chamber. A toner conveying member that supplies the toner supplied from the toner replenishing chamber to the developer containing chamber from the toner supply port, and the toner conveying member rotates. An auger having a spiral blade provided around the shaft, and in the vicinity of the toner supply port, at a position facing the toner supply port, the auger shaft has a smaller diameter than other parts. It is configured and provided with a pulverizing means for pulverizing the toner supplied to the developer accommodating chamber or the supplied toner .

According to the fifth aspect of the present invention, the auger shaft is made thinner at the position facing the toner supply port than at the other part (the position not facing the toner supply port). As a result, the toner mass transported to the position facing the toner supply port has a gap between the shaft at the position facing the toner supply port and the degree of freedom of movement increases rapidly. While moving, the adhesion force between the toners is weakened and the toner tends to be crushed.

According to a sixth aspect of the present invention, there is provided a developer containing chamber in which a developer composed of toner and a carrier is accommodated, and the developer is conveyed to the developer carrying member while the toner and the carrier are mixed and agitated by the developer agitating and conveying member. A toner replenishing chamber that accommodates toner to be supplied to the developer accommodating chamber; a dispense chamber that is provided between the toner replenishing chamber and the developer accommodating chamber and that replenishes toner in the toner replenishing chamber; A toner supply port formed on a wall of the dispensing chamber on the developer storage chamber side, a part of which is provided below the surface position of the developer stored in the developer storage chamber, and provided in the dispense chamber. A toner conveying member that supplies the toner supplied from the toner replenishing chamber to the developer containing chamber from the toner supply port, and the toner conveying member rotates. Consists of auger having a spiral blade provided around the shaft, wherein the toner supply opening neighborhood, a shaft portion to which the disposed parallel to the axis of the auger is provided in the developer accommodating chamber, the shaft A rotator which is provided in a portion and is rotatable and is rotated by being pressed by the toner fed from the toner supply port , and pulverizing means for pulverizing the toner supplied to the developer storage chamber is provided. It is characterized by that.

According to the sixth aspect of the present invention, the bulk toner supplied from the toner supply port to the developer storage chamber is pulverized by the pulverizer.

Further, a rotating body provided on a shaft arranged in parallel with the shaft of the auger is rotated by the toner supplied from the toner supply port to the developer storage chamber, and pulverizes the bulk toner.

According to a seventh aspect of the present invention, there is provided a rotatable image carrier in which an electrostatic latent image is formed on an outer peripheral surface and a toner is attached by the developer carrier to be visualized. And a developing device according to any one of Items 6 to 6 .

According to the seventh aspect of the present invention, the process cartridge according to the seventh aspect is an image carrier in which an electrostatic latent image formed on the outer peripheral surface is visualized with toner by a developing device and a developer carrier. Has a body. For this reason, a uniform toner image is formed on the image carrier.

The present invention described in claim 8 has the process cartridge described in claim 7 .

According to the invention described in claim 8 , since this image forming apparatus has the process cartridge described in claim 7 , it is possible to obtain a stable image by mixing toner in a uniform state.

  Since the present invention is configured as described above, even if the toner is supplied in the lateral direction, the toner can be supplied to the developer storage chamber without forming a lump of toner, and the toner can be uniformly mixed in the developer.

The developing device 64 according to the first embodiment of the present invention will be described below with reference to the drawings.
(Outline of image forming apparatus)
FIG. 1 shows a schematic configuration diagram of an image forming apparatus 10 equipped with a developing device 64 according to the first embodiment of the present invention.

  In the image forming apparatus 10, process cartridges 14 of four colors (in this embodiment, yellow, magenta, cyan, and black) are arranged in the vertical direction.

  As shown in FIG. 2, the process cartridge 14 includes a photoconductor cartridge 62 having a photoconductor drum 16 and a developing device 64 (details will be described later).

  The photosensitive cartridge 62 includes a photosensitive drum 16, a cleaning device 22 disposed around the photosensitive drum 16, a charging roll 18, an erase lamp 24, and a sub toner replenishing unit disposed in the lateral direction of the cleaning device 22. 66 are integrated with each other.

  The sub toner replenishing unit 66 is provided with a pair of support protrusions 78 extending in a direction orthogonal to the axial direction of the photosensitive drum 16. By inserting the support protrusion 78 into a cartridge receiving portion (not shown) of the image forming apparatus 10, the process cartridge 14 is mounted on the image forming apparatus 10.

  On the other hand, at the lower part of the image forming apparatus 10, a paper feed cassette 26 in which the paper P is stored is provided. In the vicinity of the paper feed cassette 26, a pickup roll 28 for feeding the paper P at a predetermined timing is provided. The paper P sent out from the paper feed cassette 26 by the pickup roll 28 is sent to the paper transport path 34 through the transport roll 30 and the registration roll 32 and transported to the transport device 48 described later.

  On the other hand, the process cartridge 14 is arranged in the order of yellow, magenta, cyan, and black from the upstream side of the paper conveyance path 34. On the left side of the process cartridge 14, the process cartridge 14 is scanned with light. Is provided.

  In the exposure device 36, a semiconductor laser (not shown), a polygon mirror 40, an image forming lens 44, and a mirror 46 are disposed in a housing 38. Light from the semiconductor laser is deflected and scanned by the polygon mirror 40, and connected. The photosensitive drum 16 is irradiated through the image lens 44 and the mirror 46. Thereby, a latent image corresponding to the image information is formed on the photosensitive drum 16.

  Further, a conveying device 48 is disposed on the right side of the image forming apparatus 10 in the drawing (a position facing the photosensitive drum 16). The conveying device 48 includes a pair of stretching rolls 51 and 52 provided along the side wall 10 </ b> A of the image forming apparatus 10, and a conveying belt 53 wound around the stretching rolls 51 and 52. The tension roll 52 is rotated by a motor (not shown) so that the transport belt 53 moves.

  A suction roll 55 is disposed in the vicinity of the tension roll 51, and the sheet P is electrostatically attracted to the transport belt 53 by applying a voltage to the suction roll 55. Yes.

In addition, transfer rolls 54 are disposed on the back surface of the conveyor belt 53 at positions facing the photosensitive drums 16 of the respective colors. The toner image on the photosensitive drum 16 is transferred onto the paper P conveyed by the conveying belt 53 by the transfer roll 54 and fixed by the fixing device 56. Then, the paper P on which the toner image is fixed is discharged to the discharge tray 60 by the discharge roll 58.
(Outline of the developing device)
Next, the developing device 64 according to the embodiment of the present invention will be described. 3 shows a sectional view of the developing device 64 as viewed from the axial direction of the photosensitive drum 16, and FIG. 4 shows a view of the developing device 64 as viewed from above.

  The developing device 64 in the present embodiment employs a two-component developing system, and as shown in FIG. 3, the electrostatic latent image on the photosensitive drum 16 that faces the photosensitive drum 16 is transferred to toner and a carrier. A developing unit 68 that visualizes an image with the developer G and a main toner supply unit 70 that supplies toner T to the developing unit 68 are integrated in the lateral direction.

  The developing unit 68 has a housing 80. The housing 80 is provided on the lower side of the photosensitive drum 16 and has an opening 82 that opens toward the photosensitive drum 16. Further, a developer storage chamber 84 is formed in the housing 80, and the developer G made of toner and carrier can be stored in the developer storage chamber 84.

  Further, a developing roll 86 is disposed in the housing 80 so as to be partially exposed from the opening 82 of the housing 80, and is rotatably supported on the peripheral wall of the housing 80. A gear (not shown) is fixed to the end portion of the developing roll 86, and the rotational force from the motor is transmitted to the gear so that the developing roll 86 is rotated via the gear.

  The developing roller 86 adsorbs the carrier contained in the developer G by a magnetic force, forms a magnetic brush of the developer G on the surface, and conveys the toner adsorbed on the carrier to a developing area facing the photosensitive drum 16. To do. Then, the electrostatic latent image formed on the photosensitive drum 16 is visualized by a magnetic brush of developer G made of carrier and toner formed on the surface of the developing roll 86.

  A first agitating / conveying auger 88 and a second agitating / conveying auger 89 are disposed below the developing roll 86 along the axial direction of the developing roll 86.

  The first stirring / conveying auger 88 and the second stirring / conveying auger 89 are respectively provided with rotating shafts 88 a and 89 a, and are rotatably supported on the peripheral wall of the housing 80. Spiral blades 88b and 89b are spirally wound around the rotating shafts 88a and 89a of the first stirring and transporting auger 88 and the second stirring and transporting auger 89 at a predetermined pitch.

  Gears (not shown) are fixed to the end portions of the rotary shafts 88a and 89a, respectively, and a rotational force from a motor (not shown) is transmitted to the gears, and the first agitation transport auger 88 and the second agitation transport auger via the gears. When each 89 rotates, the developer G accommodated in the developer accommodating chamber 84 is conveyed in the direction of the arrow in FIG. 4 while being stirred by the spiral blades 88b and 89b.

  A partition wall 90 is formed between the first stirring and transporting auger 88 and the second stirring and transporting auger 89, and the first stirring and transporting auger 88 is disposed in the developer storage chamber 84 by the partition wall 90. It is divided into an area (first stirring path) 92 and an area (second stirring path) 93 in which the second stirring / conveying auger 89 is provided.

  As shown in FIG. 4, communication ports 94 and 95 are formed at both ends of the partition wall 90 in the longitudinal direction. The first stirring path 92 and the second stirring path 93 are communicated with each other through the communication ports 94 and 95, and the developer G in the developer storage chamber 84 is supplied to the first stirring / transporting auger 88 and the second stirring / transporting auger 89. , The developer G is conveyed while being stirred in the first stirring path 92 and the second stirring path 93, and the developer G circulates between the first stirring path 92 and the second stirring path 93. .

  As shown in FIG. 3, the main toner supply unit 70 adjacent to the developing unit 68 is provided with a toner storage chamber 150 in which the supply toner T is stored. A toner stirring and conveying member 152 is provided in the toner storage chamber 150 along the axial direction of the developing roll 86.

  The toner agitating / conveying member 152 includes a rotation shaft 152 a and is rotatably supported on the peripheral wall of the housing 80. Blades 152b are formed on the rotating shaft 152a at a predetermined pitch. As the toner stirring and conveying member, an agitator configured by attaching a film in the radial direction of the rotation shaft 152a and cutting the film in an oblique direction may be used.

  A gear (not shown) is fixed to the end of the rotating shaft 152a. When a rotational force from a motor (not shown) is transmitted to the gear, and the toner agitating / conveying member 152 rotates via the gear, the blade 152b causes the toner storage chamber. The toner T in 150 is conveyed in the direction of the arrow in FIG. 4 while being stirred.

  On the other hand, a wall portion 154 is provided between the toner storage chamber 150 and the developer storage chamber 84. From the lower part of the wall portion 154, the curved wall 156 extends toward the toner storage chamber 150, and the partition wall 157 extends toward the developer storage chamber 84, so that a tunnel-shaped dispense chamber is formed between the bottom plates of the housing 80. 158 is configured.

  As shown in FIG. 4, an opening 162 is formed in the vicinity of one end of the curved wall 156 in the longitudinal direction so as to communicate the toner storage chamber 150 and the dispense chamber 158. As a result, the toner T stored in the toner storage chamber 150 is transported through the toner storage chamber 150 while being stirred by the toner stirring and transporting member 152, and is sent to the dispensing chamber 158 from the opening 162.

  On the other hand, a toner supply port 164 is formed in the vicinity of the other end in the longitudinal direction of the partition wall 157 so as to communicate the dispense chamber 158 and the developer storage chamber 84. As a result, the toner T in the dispense chamber 158 is conveyed through the dispense chamber 158 while being stirred by a dispense auger 160, which will be described later, and sent to the developer storage chamber 84 from the toner supply port 164.

  As shown in FIG. 3, the toner supply port 164 is formed so that the lower end portion is positioned below the surface position of the developer G stored in the developer storage chamber 84. As a result, at least a part of the toner supply port 164 is buried in the developer G accommodated in the developer accommodating chamber 84, and the toner T sent from the dispense chamber 158 to the developer accommodating chamber 84 is transferred. The developer G sinks into the developer G and is easily mixed with the developer G accommodated in the developer accommodating chamber 84.

  A dispense auger 160 is disposed in the dispense chamber 158 along the longitudinal direction (along the axial direction of the developing roll 86). The dispense auger 160 has substantially the same configuration as the first agitating / conveying auger 88 and the second agitating / conveying auger 89, and includes a rotating shaft 160a and is rotatably supported on the peripheral wall of the housing 80 as shown in FIG. Has been. The blades 160b are wound around the rotating shaft 160a in a spiral shape at a predetermined pitch.

  A gear (not shown) is fixed to the end of the rotating shaft 160a. When a rotational force from a motor (not shown) is transmitted to the gear and the dispense auger 160 rotates via the gear, the blade 160b causes the inside of the dispensing chamber 158 to move. The toner T is conveyed in the direction of the arrow in FIG. 4 while being stirred.

  A plate piece 166 is formed on the rotation shaft 160 a of the dispense auger 160 at a position facing the toner supply port 164. The plate piece 166 protrudes in the radial direction of the rotation shaft 160 a, and the longitudinal direction is provided along the axis of the rotation shaft 160 a of the dispense auger 160.

  As a result, when the toner T conveyed in the dispensing chamber 158 by the rotation of the dispensing auger 160 reaches a position facing the toner supply port 164, the toner T is stirred by the blade 160b and at the same time by the plate piece 166. It is like that. Then, the toner is supplied from the toner supply port 164 to the developer storage chamber 84 while being agitated by the blade 160 b and the plate piece 166.

  Next, the operation of the first embodiment of the present invention will be described.

  The toner T stored in the toner storage chamber 150 is fed into the dispense chamber 158 and is conveyed to the toner supply port 164 while being stirred in the dispense chamber 158 by the dispense auger 160 disposed in the dispense chamber 158. The toner T conveyed to the toner supply port 164 is supplied from the toner supply port 164 to the developer storage chamber 84.

  At this time, the toner T conveyed while being stirred in the dispense chamber 158 is compressed between the blades 160b and 160b of the dispense auger 160 to form a lump. That is, a toner lump having the pitch of the blade 160 b is formed in the dispense chamber 158 by the blade 160 b of the dispense auger 160.

  When the toner mass is conveyed to the vicinity of the toner supply port 164, it is pulverized by the plate piece 166 formed on the rotating shaft 160a of the dispense auger 160. When the toner lump is pulverized, the toner becomes fine (a state close to that before the lump) and is supplied from the toner supply port 164 to the developer storage chamber 84.

  In this way, by supplying the toner T to the developer storage chamber 84 in a fine state, the toner T can be easily embedded in the developer G. Therefore, even if the toner T is continuously supplied in large quantities, the toner T is developed. There is no floating above the agent G, and no toner lump remains in the developer G. As a result, the stirrability of the toner T supplied to the developer storage chamber 84 is improved, and the toner T is mixed in the developer G in a uniform state.

  Further, even when the toner T near the toner supply port 164 becomes a lump due to mutual adhesion, the toner lump enters the developer accommodating chamber 84 because it is pulverized by the plate piece 166 near the toner supply port 164. Can be prevented.

  Further, by providing the longitudinal direction of the plate piece 166 along the axial direction of the rotation shaft 160a of the dispense auger 160, the plate piece 166 is rotated with respect to the toner T when the plate piece 166 is rotated by the rotation of the dispense auger 160. Since the contact is made in a wide area, the toner T can be efficiently pulverized.

  In the present embodiment, as shown in FIG. 5, a plate piece 166 is provided along the axial direction of the rotation shaft 160a at a position facing the toner supply port 164 of the rotation shaft 160a of the dispense auger 160. The plate piece 166 is not limited to the shape shown in FIG.

  For example, as shown in FIG. 6, a spiral plate 168 made of a spiral plate material may be provided on the peripheral surface of the rotating shaft 160a so as to be parallel to the blade 160b. Thus, the rotation of the dispense auger 160 causes the spiral plate 168 to perform the same operation as the rotation of the blade 160b, so that the toner T is pulverized by being stirred by the blade 160b and being stirred by the spiral plate 168. Therefore, the toner can be pulverized efficiently.

  Next, a developing device according to a second embodiment of the present invention will be described. In addition, the description about the part similar to 1st Embodiment is omitted.

  As shown in FIG. 7, blades 170 b are formed at a predetermined pitch on the peripheral surface of the rotating shaft 170 a of the dispense auger 170, and at a position facing the toner supply port 164, the pitch of the blades 170 b is different from that of the other. The position is smaller than the position (position not facing the toner supply port 164). That is, in the vicinity of the toner supply port 164, the blade 170c is provided between the blade 170b and the blade 170b formed at a predetermined pitch.

  As a result, when the dispensing auger 170 is transported through the dispensing chamber 158, a large-toner toner block having a pitch of the blades 170b formed in the dispensing chamber 158 is transported to the vicinity of the toner supply port 164, and the blades 170b and 170b. Are crushed by the blades 170c provided between the two.

  In the present embodiment, the pitch of the blades 170b is made smaller than the other positions at the position facing the toner supply port 164. On the contrary, at the position facing the toner supply port 164. The blade pitch may be larger than other positions. In this case, the large-pitch toner mass conveyed to the position facing the toner supply port 164 by the dispense auger is pulverized while moving between the blades. In other words, since the distance between the blades is larger than the size of the toner mass, a gap is generated around the toner mass in the axial direction, and the degree of freedom of movement of the toner mass increases rapidly, so the toner mass moves. However, the adhesion force between the toners is weakened and the toner tends to be crushed.

  Next, a developing device according to a third embodiment of the present invention will be described. In addition, the description about the part similar to 1st Embodiment is omitted.

  As shown in FIG. 8, the diameter of the rotation shaft 172 a of the dispense auger 172 is made thinner at the position facing the toner supply port 164 than the other portions at the position facing the toner supply port 164.

  As a result, the toner mass having a large pitch of the blades 172b conveyed by the dispense auger 172 has a gap between the shaft at a position facing the toner supply port 164, and the degree of freedom of movement rapidly increases. While the lump moves, the adhesion force between the toners is weakened and the lump is easily pulverized.

  Next, a developing device according to a fourth embodiment of the present invention will be described. In addition, the description about the part similar to 1st Embodiment is omitted.

  As shown in FIGS. 9 and 10, a crusher 176 is provided in the vicinity of the toner supply port 164 of the developer storage chamber 84. The crushing device 176 has a shaft 176a provided along the axial direction of the developing roll 86, and a rotating body 176b is provided on the peripheral surface of the shaft 176a so as to be rotatable with respect to the shaft 176a. The rotating body 176b is composed of four long plates provided at a 90 ° pitch around the shaft 176a, and is provided so that the longitudinal direction is parallel to the axial direction of the shaft 176a.

  The rotator 176b is provided only in the vicinity of the toner supply port 164, and the rotator 176b receives pressure from the toner T sent from the toner supply port 164. That is, the rotating body 176b is configured to rotate by being pressed by the toner T sent from the toner supply port 164.

  Thus, when the toner T is supplied from the toner supply port 164 to the developer storage chamber 84, the toner is pulverized by the rotation of the rotating body 176b even if the toner is in a lump shape. Then, the toner T that has been pulverized into a fine state is supplied into the developer G.

  Further, when the rotating body 176b of the crushing device 176 rotates, the developer G in the developer storage chamber 84 is preliminarily stirred. Thereby, the lumped toner can be efficiently sunk into the developer G while being pulverized by the rotating body 176b.

In the present embodiment, the rotating body 176b is configured by providing four plate-like members around the shaft 176a at a 90 ° pitch. However, the rotating body 176b rotates around the shaft and collects a block of toner near the toner supply port 164. The shape of the rotating body is not limited to this state as long as it can be pulverized.
<Example>
In the developing device 64 shown in FIG. 3, the blade pitch is changed over the entire area, as shown in FIG. 5, a plate piece 166 is provided between the blades at a position facing the toner supply port 164, and FIG. As shown in FIG. 8, the pitch of the blades is changed between the vicinity of the toner supply port 164 and other positions, or the rotation shaft 172a is positioned at a position facing the toner supply port 164 as shown in FIG. An experiment was conducted to determine whether the state of the toner T supplied to the developer accommodating chamber 84 changes by reducing the diameter.

  At this time, the pitch of the spiral blades 88a and 89a of the first stirring and transporting auger 88 and the second stirring and transporting auger 89 was set to 15 mm.

  The results of the above examples are shown in Table 1.

The dispense auger was rotated under the following conditions.
Condition 1: Rotating for 0.5 s and stopping for 0.5 s for 20 s Condition 2: Rotating continuously for 5 s Condition 3: Rotating continuously for 10 s In addition, the evaluation at that time was performed as follows .
A: No toner lump remains in the vicinity of the toner supply port 164 B: Some toner lump remains in the toner supply port 164 B: Upper portion of the flow of the developer G downstream of the toner supply port 164 (in the developer storage chamber 84) X: Some toner lump remains x: Large toner lump remains at the downstream of the toner supply port 164 or at the upper part of the flow of the developer G

表１から、ディスペンスオーガーの回転軸にトナー供給口１６４に対向する位置で板片１６６を設けたとき、回転軸１７２の径を細くしたとき、トナー供給口１６４に対向する位置とその他の位置とで羽根のピッチを変化させたときに、トナー供給口１６４付近にトナー塊の残留がほとんど見られず、トナー塊は粉砕されて、現像剤収容室８４の現像剤Ｇ中に均一な状態でトナーを混合させることができることがわかる。

From Table 1, when the plate piece 166 is provided at the position facing the toner supply port 164 on the rotation axis of the dispense auger, when the diameter of the rotation shaft 172 is reduced, the position facing the toner supply port 164 and other positions When the blade pitch is changed, the toner lump remains almost in the vicinity of the toner supply port 164, and the toner lump is crushed and uniformly in the developer G in the developer accommodating chamber 84. It can be seen that can be mixed.

1 is a schematic configuration diagram of an image forming apparatus equipped with a developing device according to a first embodiment of the present invention. 1 is a schematic configuration diagram of a process cartridge in which a developing device according to a first embodiment of the present invention is mounted. 1 is a side cross-sectional view of a developing device according to a first embodiment of the present invention. 1 is a top view of a developing device according to a first embodiment of the present invention. FIG. 3 is a side view showing a part of a dispense auger provided in the developing device according to the first embodiment of the present invention. It is a side view which shows a part of dispense auger which concerns on other embodiment of this invention. FIG. 10 is a side view showing a part of a dispense auger provided in a developing device according to a second embodiment of the present invention. It is a side view which shows a part of dispensing auger provided in the developing device which concerns on the 3rd Embodiment of this invention. It is side surface sectional drawing of the developing device which concerns on the 4th Embodiment of this invention. It is a top view of the developing device concerning a 4th embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 14 Process cartridge 64 Developing device 84 Developer storage chamber 86 Developing roll (developer carrier)
88 Stirring transport auger (Developer stirring transporting member)
89 Stirring transport auger (Developer stirring transporting member)
150 Toner storage chamber (toner supply chamber)
158 Dispense chamber 160 Dispense auger (toner conveying member, auger)
160a shaft 160b blade 164 toner supply port 166 plate piece (pulverization means, protrusion)
168 Spiral plate (grinding means, protrusions)
176 Crusher (Crushing means)
176a Shaft 176b Rotating body

Claims (8)

A developer containing chamber in which a developer composed of toner and a carrier is accommodated, and the developer is conveyed to the developer carrying member while the toner and the carrier are mixed and agitated by a developer agitating and conveying member;
A toner replenishing chamber in which toner to be supplied to the developer accommodating chamber is accommodated;
A dispensing chamber provided between the toner replenishing chamber and the developer accommodating chamber, in which toner in the toner replenishing chamber is replenished;
A toner supply port formed on a wall of the dispensing chamber on the developer storage chamber side, a part of which is located below the surface position of the developer stored in the developer storage chamber;
A toner conveying member provided in the dispensing chamber and configured to supply the toner supplied from the toner replenishing chamber to the developer accommodating chamber from the toner supply port;
In a developing device having
The toner conveying member is composed of an auger having a spiral blade provided around a rotating shaft,
In the vicinity of the toner supply port, there is provided a protrusion provided at a position facing the toner supply port of the shaft, and a pulverizing means for pulverizing the toner supplied to the developer storage chamber or the supplied toner is provided. A developing device characterized by that.   The developing device according to claim 1, wherein the protrusion is a plate piece provided along an axial direction of the shaft.   The developing device according to claim 1, wherein the protrusion is a spiral plate provided in parallel with the blade. A developer containing chamber in which a developer composed of toner and a carrier is accommodated, and the developer is conveyed to the developer carrying member while the toner and the carrier are mixed and agitated by a developer agitating and conveying member;
A toner replenishing chamber in which toner to be supplied to the developer accommodating chamber is accommodated;
A dispensing chamber provided between the toner replenishing chamber and the developer accommodating chamber, in which toner in the toner replenishing chamber is replenished;
A toner supply port formed on a wall of the dispensing chamber on the developer storage chamber side, a part of which is located below the surface position of the developer stored in the developer storage chamber;
A toner conveying member provided in the dispensing chamber and configured to supply the toner supplied from the toner replenishing chamber to the developer accommodating chamber from the toner supply port;
In a developing device having
The toner conveying member is composed of an auger having a spiral blade provided around a rotating shaft,
In the vicinity of the toner supply port, the pitch of the blades of the auger is made different at a position facing the toner supply port so as to be smaller or larger than a position not facing the toner supply port. A developing device comprising a toner supplied to the agent storage chamber or a pulverizing unit for pulverizing the supplied toner. A developer containing chamber in which a developer composed of toner and a carrier is accommodated, and the developer is conveyed to the developer carrying member while the toner and the carrier are mixed and agitated by a developer agitating and conveying member;
A toner replenishing chamber in which toner to be supplied to the developer accommodating chamber is accommodated;
A dispensing chamber provided between the toner replenishing chamber and the developer accommodating chamber, in which toner in the toner replenishing chamber is replenished;
A toner supply port formed on a wall of the dispensing chamber on the developer storage chamber side, a part of which is located below the surface position of the developer stored in the developer storage chamber;
A toner conveying member provided in the dispensing chamber and configured to supply the toner supplied from the toner replenishing chamber to the developer accommodating chamber from the toner supply port;
In a developing device having
The toner conveying member is composed of an auger having a spiral blade provided around a rotating shaft,
In the vicinity of the toner supply port, the auger shaft has a smaller diameter than other parts at a position facing the toner supply port, and the toner supplied to or supplied to the developer storage chamber A developing device provided with a pulverizing means for pulverizing the liquid. A developer containing chamber in which a developer composed of toner and a carrier is accommodated, and the developer is conveyed to the developer carrying member while the toner and the carrier are mixed and agitated by a developer agitating and conveying member;
A toner replenishing chamber in which toner to be supplied to the developer accommodating chamber is accommodated;
A dispensing chamber provided between the toner replenishing chamber and the developer accommodating chamber, in which toner in the toner replenishing chamber is replenished;
A toner supply port formed on a wall of the dispensing chamber on the developer storage chamber side, a part of which is located below the surface position of the developer stored in the developer storage chamber;
A toner conveying member provided in the dispensing chamber and configured to supply the toner supplied from the toner replenishing chamber to the developer accommodating chamber from the toner supply port;
In a developing device having
The toner conveying member is composed of an auger having a spiral blade provided around a rotating shaft,
In the vicinity of the toner supply port, a shaft portion provided in the developer accommodating chamber and disposed in parallel with the axis of the auger, and a toner provided on the shaft portion and rotatable and fed from the toner supply port And a rotator that rotates when pressed against the developing device, and provided with a pulverizing means for pulverizing the toner supplied to the developer storage chamber.   7. The rotatable image bearing member according to claim 1, wherein an electrostatic latent image is formed on an outer peripheral surface, and a toner is attached by the developer bearing member to be visualized, and a rotatable image bearing member. And a developing device.   An image forming apparatus comprising the process cartridge according to claim 7.

Images