JP3247006B2 - Toner supply device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a toner storage portion outside the image forming area in the width direction of a latent image carrier, and conveys toner from the toner storage portion onto a toner supply portion of a developing device. The present invention relates to a toner replenishing device that replenishes toner with a predetermined width to a toner replenishing unit.

[0002]

2. Description of the Related Art In an image forming apparatus such as a printer, a copying machine, a facsimile, etc.
Replacing the toner bottle and the toner cartridge is a troublesome operation. Therefore, it is required to increase the interval at which the toner ends, and as a method of satisfying the requirement, an attempt has been made to increase the toner capacity stored in the apparatus. In this case, it is difficult to secure a space for increasing the toner capacity within the width of the image forming range, and it is general to provide a toner storage section in front of the image forming section.

In such a configuration, toner is transported from a toner storage section to a toner replenishing section above the developing apparatus, and replenished to a developing chamber of the developing apparatus via a toner replenishing mechanism such as a toner replenishing roller. At this time, the means for transporting the toner from the toner storage unit to the toner replenishment unit has two functions of transporting the toner from the near side to the back side in the toner replenishment unit and uniformly replenishing the toner within the range of the toner replenishment unit. Was needed.

It is extremely difficult to fulfill both of these functions with a single transport member. If the transport is excessive, solidification or blocking of the toner will occur in the middle of the path, and if the transport is insufficient, the toner will be located near and far from the toner supply area. In this case, a difference occurs in the amount of toner supplied to the developing chamber, and the deviation in the amount of toner supplied to the developing chamber causes problems such as deterioration of image quality. In order to solve such a problem, for example, Japanese Patent Application Laid-Open No. 60-84556 discloses a method of providing a toner conveying tube from a toner box to a developing machine, and arranging two augers having different forward and reverse rotations and rotation directions in the tube. It is disclosed that toner is supplied by the auger. As described above, by providing the conveying member for conveying the toner from the near side to the back side and the other conveying member for returning the toner from the back side to the near side, the solidification and blocking of the toner can be prevented, and the deviation of the toner supply amount to the developing chamber can be prevented. According to this method, deterioration of image quality is prevented.

[0005]

However, in the above-mentioned conventional toner replenishing device, since two transport members are provided, the space occupied by the developing device is increased and the cost is increased. In particular, recently, there has been a demand for space-saving of the entire apparatus, which hinders such a demand. Further, in order to make the toner supply within a predetermined width of the toner supply section uniform, there have been proposed means such as providing sensors on the near side and the back side, but this also leads to an increase in cost. there were.

[0006] The present invention solves the above-mentioned conventional problems,
It is an object of the present invention to provide a small-sized and low-cost toner supply device.

[0007]

In order to achieve the above object, the present invention has a toner storage portion outside the image forming area in the width direction of a latent image carrier, and replenishes toner from the toner storage portion to a developing device. A toner agitating and transporting a toner from the toner storage unit to the toner replenishing unit while the toner is being transported to the toner replenishing unit, the toner replenishing device supplying the toner to a toner replenishing area having a predetermined width in the toner replenishing unit. A member is provided, and the toner stirring and conveying member is provided with a rotating shaft, an arm provided at a predetermined angle to the rotating shaft, and a spiral plate extending in a longitudinal direction connected to the tip of the arm and extending in a spiral manner. A slope is formed on the surface of the spiral plate in the toner replenishment area, and the inclination is relative to radiation of the rotating shaft passing through one end of the spiral plate in the rotation direction upstream in the short direction. It is characterized in that one end of the rotating direction upstream side in the short direction of the spiral plate the slope approaching to the rotation axis than the one end of the downstream side in the rotational direction.

The present invention is effective when the inclination angle of the spiral plate is in the range of 10 ° to 70 °.

[0009]

[0010]

[0011]

[0012]

[0013]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 and 2 are a front explanatory view and a plan explanatory view schematically showing a developing device provided with a toner supply device according to the present invention.

In FIGS. 1 and 2, reference numeral 1 denotes a drum-shaped photosensitive member as a latent image carrier, and reference numeral 2 denotes a developing device arranged to face the photosensitive member 1. The developing device 2 includes a developing chamber 3 and a hopper 4 serving as a toner replenishing unit for replenishing the developing chamber 3 with toner. The developing chamber 2 includes a developing roller 5 and the like arranged opposite to the photoconductor 1. are doing. Further, the toner in the hopper 4 is supplied to the developing chamber 3 by the toner supply roller 6 in accordance with the amount of consumed toner. The hopper 4 has no capacity for storing a large amount of toner, and therefore, a toner bottle 7 is provided in front of the image forming unit. In this case, hopper 4
Is extended to the position of the toner bottle 7, and the toner contained in the toner bottle 7 is dropped into the hopper 4 from the toner receiving port 12 formed at that position.

In the hopper 4, as shown in FIGS. 1 to 3, a rotating shaft 8 whose axis is parallel to the axis of the toner replenishing roller 6 is provided, and the rotating shaft 8 is rotated counterclockwise by a driving device (not shown). Is driven to rotate. The rotating shaft 8 is provided with an arm 9 whose angle is changed by a predetermined angle at predetermined intervals so as to protrude, and a spiral plate 10 is connected to a tip of the arm 9. The spiral plate 10 has an elongated plate member attached to the arm 9 such that the longitudinal direction is spiral. The rotation shaft 8, the arm 9 and the spiral plate 10 constitute a toner stirring and conveying member 11. When the toner stirring and conveying member 11 rotates, the toner is conveyed from the near side to the back side and the toner in the hopper 4 is stirred. I do.

The toner replenishing apparatus having the above-described structure can reliably transport the toner to the toner replenishing area A having a predetermined width shown in FIG. Since the plate 10 passes through the hollow portion formed because the plate 10 is attached to the arm 9, excessive conveyance is prevented.

Thus, the toner stirring and conveying member 11 can surely convey the toner, and can keep the toner bulk in the hopper 4 uniform. Accordingly, a transport member for transporting the toner in the reverse direction is not required, so that the cost and space are reduced.

The toner stirring and conveying member 11 is a spiral plate 1
The helix angle of the helical shape of 0 is not uniform, and the conveying speed is set near the toner bottle 7 at an angle at which the conveying speed increases, and the conveying speed downstream from the toner supply area A is lower than that near the toner bottle 7. Set.

With this configuration, the toner bottle 7
Can be quickly conveyed in the vicinity of, the toner supply to the hopper 4 can be started quickly when there is no new toner in the hopper 4 or at the time of recovery after the toner end. In addition, it is possible to prevent an unnecessary conveyance speed from being generated on the downstream side in the conveyance direction in which the toner is relatively accumulated, thereby applying stress to the toner.

Further, the toner agitating and conveying member 11 is provided with a helical plate 10 so that the toner is returned downstream of the toner replenishing area A by the rotation of the rotary shaft 8, that is, the toner is conveyed from the back side to the near side. May be reversed. In this way, the toner that has been excessively conveyed beyond the toner replenishment area A is returned to the toner replenishment area A, and waste of the toner is eliminated.

Further, as shown in FIG.
Is formed on the surface of. The inclination of the spiral plate 10 is such that, with respect to the radiation L of the rotating shaft 8 passing through one end of the spiral plate 10 in the rotational direction upstream in the short direction, one end of the spiral plate 10 in the rotational direction upstream in the short direction is downstream in the rotational direction. The inclination is closer to the rotation axis 8 than one end on the side. When the inclination angle is θ, the angle θ is set in a range of 10 ° to 70 °.

With this configuration, the toner stirring and conveying member 11
Rotates while storing the toner in the spiral plate 10, and can reliably supply the toner to the toner supply roller 6.
A stable toner supply amount can be maintained. This effect can be similarly obtained in a toner replenishing device of a type in which the toner replenishing roller 6 is located above the toner stirring and conveying member 11.

In the above embodiment, the spiral stirring plate 10 is a toner stirring / conveying member 11 which is divided at a predetermined interval and is continuously provided. However, the spiral stirring plate 10 may be a continuous one. May be provided on the opposite side of the rotating shaft 8 alternately. When the spiral plates 10 are provided alternately on the opposite side of the rotating shaft 8, the toner stirring and conveying member 11
A mold can be used to form the toner. In this case, if the mold is removed from the vertical direction in FIG. 4, the expensive mold can be divided in two directions. The transport member 11 can be manufactured at low cost.

[0024]

According to the present invention, an inclination is formed on the surface of the spiral plate in the toner replenishment area, and the inclination is reduced with respect to the radiation of the rotating shaft passing through one end of the spiral plate in the rotation direction upstream in the short direction. Since one end on the upstream side in the rotation direction in the short direction of the spiral plate is inclined closer to the rotation axis than one end on the downstream side in the rotation direction, the toner stirring and conveying member rotates while accumulating toner by the spiral plate and supplies toner. The toner can be reliably supplied to the roller, and a stable toner supply amount can be maintained.

[0025]

[0026]

[0027]

[0028]

[Brief description of the drawings]

FIG. 1 is an explanatory front view schematically showing a developing device provided with a toner supply device according to the present invention.

FIG. 2 is an explanatory plan view of FIG. 1;

FIG. 3 is a perspective view of the toner supply device according to the present invention.

FIG. 4 is an explanatory diagram showing an inclination of a spiral plate of the toner stirring and conveying member.

[Explanation of symbols]

 2 Developing device 3 Developing room 4 Hopper 7 Toner bottle 8 Rotating shaft 9 Arm 10 Spiral plate 11 Toner stirring and conveying member

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-180876 (JP, A) JP-A-58-219575 (JP, A) JP-A-3-102377 (JP, A) JP-A-5-219377 127519 (JP, A) Fully open 1986-70863 (JP, U) Fully open 3-1253 (JP, U) Fully open, 2-95351 (JP, U) Fully open 1986-162870 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) G03G 15/08

Claims (2)

(57) [Claims] An image forming apparatus includes: a toner storage unit provided outside of an image forming area in a width direction of a latent image carrier; a toner supply unit configured to transport toner from the toner storage unit to a toner supply unit of a developing device; A toner replenishing device for replenishing toner in the toner replenishment area, provided with a toner agitating and transporting member for transporting the toner from the toner storage unit onto the toner replenishing unit while agitating the toner; An arm provided at a predetermined angle on the rotation axis, and a spiral plate extending in a longitudinal direction connected to the tip of the arm and extending in a helical manner; An inclination is formed, and the inclination is such that one end on the upstream side in the rotation direction in the short direction of the spiral plate responds to the radiation of the rotating shaft passing through one end on the upstream side in the rotation direction in the short direction of the spiral plate. Toner supply device, characterized in that than the one end of the downstream side in the rotational direction is the slope approaching to the rotating shaft. 2. The inclination angle of the spiral plate is 10 ° to 70 °.
2. The toner replenishing device according to claim 1, wherein the temperature is in a range of degrees.