JP2927828B2 - Developing unit - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an electrophotographic printer, a copying machine, and a developing device in a facsimile or the like.

(Prior Art) As is well known, in an electrophotographic copying machine or the like, it is necessary to sequentially replenish toner consumed by development to a developing device. As a method of replenishing the toner, as shown in FIG. 11, a toner of a toner cartridge 3 (hopper) is inserted into a toner replenishing port 2 provided at a location of a housing 1a (generally, an upper end of the housing 1a). There is a method of replenishing the toner 5 with the supply port 4 corresponding. Here, the toner 5 stored in the toner cartridge 3 passes through the toner supply port 4 of the toner cartridge 3 and the toner supply port 2 of the developing device 1 by rotating the toner supply roller 6 of the toner cartridge 3 as necessary. Are replenished sequentially into the housing 1a of the developing device 1.

(Problems to be Solved by the Invention) Incidentally, the toner cartridge 3 described above
After the replenishment is completed, it becomes unnecessary, and therefore, it is usually removed from the developing device 1 in many cases.

Therefore, when the toner cartridge 3 is detached, the toner supply port 2 of the developing device 1 remains exposed. Therefore, in the conventional developing device 1, there is a problem that the toner 5 is scattered from the exposed toner supply port 2 due to rotation of the agitator 7 built therein and the inside of a copier or the like is contaminated. Was.

Further, the exposure of the toner 5 in the developing device 1 through the toner supply port 2 gives a dirty impression to the operator, and the image of the developing device 1 is fixed as a dirty image, so that the user can maintain the image. May not be executed in a timely manner.

As a method for solving such a problem, a shutter member urged to close the toner supply port 2 is normally provided in the developing device 1 and the toner supply port is connected to the developing device 1 of the toner cartridge 3. Exercise to the wearing action of
What is necessary is just to comprise this shutter member so that it may open against the urging force, and such a shutter mechanism can be easily remembered by those skilled in the art.

However, as described above, when the user simply gives the shutter member the habit of closing the toner supply port, the shutter member is closed in an open state in conjunction with the shutter member toner cartridge 3. A reaction force against the behavior is applied to the developing device 1.

Therefore, arranging such a shutter member easily causes an unnecessary load (external force) to be applied to the developing device 1 instead. Therefore, the developing device 1 and other image forming units (for example, This causes fluctuations in the positional relationship with the photosensitive member or the like and the pressing force, which has an unexpected adverse effect on the image to be developed.

(Means for Solving the Problems) In order to solve the above-described problems, the present invention provides a developing device that receives a supply of toner from a toner cartridge, and a shutter that is openably and closably supported to close a toner supply port of the developing device. The shutter member reaches the conceivable point in a state where the shutter member faces a substantially intermediate position between the open position and the closed position, and moves the shutter member to the open position in a state where the shutter member is displaced closer to the open position than the conceived point. And a shutter opening / closing force urging means for causing the shutter member to face the closed position in a state where the shutter member is displaced closer to the closed position than the above-mentioned thought point, and when the toner cartridge provided on the shutter member is mounted. At the same time as the toner cartridge is attached and the toner cartridge is mounted, A first engagement portion for displacing the shutter member closer to the opening position than the above-mentioned idea; and removing the toner cartridge and displacing the shutter member against the shutter opening / closing force urging means by the elasticity of a spring. Closing means for displacing the toner cartridge closer to the closing position, and a second engaging portion which is provided on the shutter member and which engages with the closing means when the toner cartridge is removed. When the device is mounted, it is configured to engage with the toner cartridge to be engaged with the second engaging portion.

(Operation) According to the present invention, the shutter opening / closing force urging means provides the shutter member with opening / closing behavior for opening / closing the toner supply port 2. Since the shutter opening / closing force urging means has a conceivable point and is arranged in the developing device main body, the urging force of the shutter opening / closing force urging device does not act as an external force on the developing device.

Further, since the shutter member has an opening behavior and a closing behavior for opening and closing the toner supply port of the developing device itself by the shutter opening / closing force urging means, the shutter member can be opened and closed at the opening position and the closing position. No external force is required to hold the shutter member.

Further, when the shutter member faces the open position and the closed position, the shutter opening / closing means does not interfere with the developing device and the shutter member.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

The shutter mechanism of the toner supply port according to the present invention has a first
As shown in the figure, it is composed of a shutter member 10, shutter opening / closing force urging means 20, shutter opening means 30, shutter closing means 40 and the like.

The shutter member 10 has a shutter surface 11 large enough to close the toner supply port 2 of the developing device 1 (see FIG. 2). The shutter member 10 is connected to the toner supply port 2 by pivotally attaching brackets 13 formed on both sides of the shutter surface 11 to the short shafts 12 provided on both sides of the housing 1a of the developing device 1. It is supported so that it can be opened freely.

As shown in FIG. 1, the shutter opening force urging means 20 includes a stud 21 provided on the bracket 13 of the shutter member 10 and another stud 22 provided on the side of the housing 1a of the developing device 1. And a spring 23 that is stretched between them. Here, the positions of the studs 21 and 22 of the shutter opening force urging means 20 are different from those of the shutter member 10.
However, the spring 23 is set so as to reach a conceivable point in a state facing a substantially intermediate position (FIG. 4) between the open position (the position in FIG. 1) and the release position (the position in FIG. 2). ing.

The shutter opening means 30 includes an opening lever 31 fixed to the toner cartridge 3 and a protruding piece 32 as a first engaging portion formed integrally with the bracket 13 of the shutter member 10 (FIG. 1). ). Here, the release lever 31 and
As shown in FIG. 3, the positional relationship between the projecting piece 32 and the toner cartridge 3 is brought into contact with each other as shown in FIG. 3, and as shown in FIG. This contact state is maintained until the shutter member 10 is displaced toward the open position, and as shown in FIG. 5, the contact state is released with the shutter member 10 facing the open position, and the shutter member 10 is separated from each other. Is set to

The shutter closing means 40 includes a closing lever 41 as a closing means and a pin 42 as a second engaging portion. Here, the closing lever 41 is a part separated from the developing device main body (including the toner cartridge 3 in this embodiment),
For example, it is disposed on a side plate (not shown) of a copying machine or the like in which the developing device 1 is disposed. As shown in FIG. 6, the closing lever 41 is rotatably supported by a support shaft 43 provided on the side plate. Further, the closing lever 41 is
In FIG. 6, the elasticity of the spring 44 wound around
The turning behavior in the direction of the arrow is urged. The normal rotation of the closing lever 41 due to the rotating behavior is prevented by the closing lever end 41a on the base side abutting against a stopper 45 formed by bending a part of the side plate.

On the other hand, the pin 42 is extended on the bracket 13 of the shutter member 10 with its end extending into the rotation path of the closing lever 41. Here, as shown in FIG. 1, the closing lever 41 is turned clockwise by the opening lever 31 in a normal state in which the shutter member 10 faces the open position, that is, in a normal state in which the toner cartridge 3 is mounted on the developing device 1. Moved, pin
It is set in advance so as to be separated from 42. In addition, the positional relationship between the stopper 45 and the closing lever end 41a is such that, with the shutter member 10 facing the closing position, the conceivable point of the spring 23 is displaced toward the closing position, and the closing lever is separated from the pin 42 at the closing position. 41 is set to stop.

The shutter mechanism configured as described above is operated as follows.

When the toner cartridge 3 is removed from the developing device 1, the toner supply port 2 of the developing device 1 is closed by the shutter surface 11 of the shutter member 10, as shown in FIG. In this state, when the mounting operation of the toner cartridge 3 is started, the release lever 31 first comes into contact with the protruding piece 32 as shown in FIG. Next, when the toner cartridge 3 approaches the developing device 1, as shown in FIG.
Reaches a thought point. When the spring 23 is displaced toward the open position beyond the conceivable point, the spring 23
The shutter member 10 is retracted to the open position by the resilience of, and the toner supply port 2 of the developing device 1 is opened as shown in FIG. As a result, the toner supply port 4 of the toner cartridge 3 corresponds to the toner supply port 2 of the developing device 1, and toner 5 is supplied as needed (see FIG. 11). At this time, the protruding piece 32 is separated from the tip of the release lever 31, and
When the closing lever 41 is pushed by the tip of the opening lever 31, the pin 42 is separated from the closing lever 41 (see FIGS. 1 and 7).

On the other hand, when the replenishment of the toner 5 is completed and the operation of removing the toner cartridge 3 from the developing device 1 is started, the closing lever 41 is moved backward as shown in FIG. Rotate clockwise. As a result, the closing lever 41 pushes up the pin 42, and the idea of the spring 23 is
The developing device 1 is displaced toward the closed position of the shutter member 10 and
Of the toner supply port 2 is the shutter surface 11 of the shutter member 10.
Closed by (See FIGS. 9 and 10).

As described above, in this shutter mechanism, the shutter member 10 is held in the open position and the closed position by its own opening behavior and closing behavior, and the shutter opening means 30 and the shutter closing means 40 are separated from the developing device 1. You. Therefore, in this shutter mechanism, the shutter member 10 that opens and closes in conjunction with the mounting operation of the toner cartridge 3 is provided in the toner supply port 2 of the developing device 1 without applying any external biasing force to the shutter member 10. can do.

(Effects of the Invention) According to the present invention, since the shutter member is opened and closed in conjunction with the mounting operation of the toner cartridge, it is possible to reliably prevent an operator's erroneous operation such as replenishing toner with the shutter member closed. In addition, the shutter can be reliably opened and closed because it exceeds the conceivable point of the shutter opening and closing force urging means only by giving a relatively small displacement to the shutter.

In addition, since the toner supply port of the developing device is securely closed by the shutter member except when toner is supplied, contamination inside the copying machine or the like due to scattering of toner and unclean impression due to exposure of toner can be eliminated. .

Further, since no external force is applied to the developing device, the shutter member can be provided without impairing the reliability of the developing device.

[Brief description of the drawings]

FIG. 1 is a side view of an embodiment of the present invention, FIGS. 2 to 5 are schematic side views showing a process of attaching a toner cartridge to a developing device in the above embodiment, and FIG. 6 is a shutter closing in the above embodiment. FIGS. 7 to 10 are schematic side views showing the process of detaching the toner cartridge from the developing device in the above embodiment, and FIG. 11 is a schematic sectional view of a conventional developing device and toner cartridge. 1 ... developing device, 2 ... toner supply port, 3 ... toner cartridge, 4 ... toner supply port, 5 ... toner, 10 ...
Shutter member, 11 ... Shutter surface, 12 ... Short axis, 20
…… Shutter opening / closing force biasing means, 21,22 …… Stud, 2
3 ... Spring, 30 ... Shutter release means, 31 ...
Open lever, 32 ... Projection, 40 ... Shutter closing means,
41 ... closing lever, 42 ... pin, 43 ... support shaft, 44 ... spring, 45 ... stopper.

Claims (1)

(57) [Claims] A developing device for receiving toner from a toner cartridge, a shutter member openably and closably closed to close a toner supply port of the developing device, and a substantially middle position of the shutter member between an open position and a closed position. The shutter member reaches the thought point in the state facing the above, and the shutter member approaches the open position in a state where the shutter member is displaced closer to the open position than the thought point, and the shutter member is closer to the closed position than the thought point. Shutter opening / closing force urging means for causing the shutter member to face the closed position in a displaced state; and a shutter opening / closing force urging device which is provided on the shutter member and which engages with the toner cartridge when the toner cartridge is mounted and which is mounted together with the toner cartridge. The shutter member is displaced closer to the open position than the conceived point against the means. A first engaging portion, closing means for displacing the shutter member against the shutter opening / closing force urging means at the same time as removing the toner cartridge, and displacing the shutter member closer to the closed position than the above-mentioned point by the elasticity of a spring; A second engagement portion with which the closing means engages when the toner cartridge provided on the member is removed,
The developing device is characterized in that the closing means engages with the toner cartridge when the toner cartridge is mounted, and is brought into engagement with the second engaging portion.