JP2000211180A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To retain an interval in the stabilized state between an opening of a head device and a toner carrying member by a simple constitution and provide stabilized images for a long period of time by guiding toner by a toner carrying member provided in a toner feeder to an opening formed on a head device and jetting the toner out of the opening to form an image. SOLUTION: In a head device provided with a sheet-shaped head device 10 with an opening 12 jetting toner (t) and a toner feeder 20 with a toner carrying member 22 guiding the toner to the opening of the head device, one end side of the head device is so held as to face the opening to the toner carrying member, and a spacer 32 being brought into contact with the toner carrying member and adjusting an interval with the toner carrying member is set on a face facing the toner carrying member, while an elastic member 33 for energizing the head device on the toner carrying member side is set on a face on the opposite side of the toner carrying member.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus used as a copying machine, a printer, or the like, in which toner is guided to an opening provided in a head device by a toner conveying member provided in a toner supply device. In an image forming apparatus in which an image is formed by discharging the toner from an opening of a head device, a feature is that the distance between the toner conveying member and the opening of the head device is kept constant. It has.

[0002]

2. Description of the Related Art Hitherto, as an image forming apparatus such as a copying machine or a printer, an electrophotographic type has been widely used.

However, in the case of an image forming apparatus using an electrophotographic method, an image is formed on a photosensitive member through processes such as charging, exposure, development, and transfer, so that the apparatus becomes complicated and costs increase. In addition, there have been various problems such as the characteristics of the photoreceptor being changed due to a change in the environment, making it impossible to form a stable image.

For this reason, in recent years, US Pat.
As shown in Japanese Patent Application Laid-Open No. 689935 and JP-A-6-206336, a roller shape for guiding charged toner to an opening of the head device is provided on one side of a head device in which openings for discharging toner are arranged. While providing a toner supply device having a toner conveyance member that has become, a back electrode for electrically sucking the toner is provided on the opposite side of the toner supply device,
The toner charged by the toner conveying member provided in the toner supply device is guided to the opening of the head device, and
The recording medium for recording is guided between the back electrode and the head device, and the voltage applied to the control electrode provided in each opening in the head device is controlled to control the ejection of the toner in each opening. There has been proposed an image forming apparatus that discharges toner from a selected opening by an electric suction force of a back electrode to form an image on a recording medium.

Here, in order to form a stable image in such an image forming apparatus, it is necessary to keep a constant distance between a toner conveying member for guiding toner to an opening in the head device and this opening. .

Therefore, conventionally, in a state where the head device in the form of a sheet is pulled, the opening thereof is opposed to the toner conveying member at a required interval.

However, if the head device is maintained in the pulled state for a long time, the head device is gradually deformed, and the position of the opening provided in the head device is shifted or the pitch between the openings changes. If the accuracy of forming or mounting the roller-shaped toner conveying member is poor, the distance between the toner conveying member and the opening may change. Thus, there is a problem that a stable image cannot be obtained.

[0008]

According to the present invention, toner is guided to an opening provided in a head device by a toner conveying member provided in a toner supply device, and the toner is discharged from the opening to form an image. It is an object of the present invention to solve the above-described problem in the image forming apparatus as described above, and to maintain a constant state between the opening of the head device and the toner conveying member by a simple configuration, It is an object to obtain a stable image over a long period of time.

[0009]

In the image forming apparatus according to the present invention, in order to solve the above-mentioned problems, a sheet-like head device provided with an opening for discharging toner, An image forming apparatus comprising: a toner supply device provided with a toner conveying member that guides toner to an opening; an image forming apparatus that holds one end of a head device so that the opening faces the toner conveying member; , A spacer is attached to the surface facing the toner conveying member to adjust the distance between the toner conveying member and the toner conveying member, and the head device is urged toward the toner conveying member toward the surface opposite to the toner conveying member. That is, an elastic member is attached.

In the image forming apparatus according to the present invention, the head device is urged toward the toner conveying member by the elastic member attached to the surface of the head device opposite to the toner conveying member, and the toner is conveyed. The spacer attached to the surface facing the member is brought into contact with the toner conveying member by the urging force of the elastic member to adjust the distance between the opening provided in the head device and the toner conveying member.

With this configuration, it is not necessary to apply a strong tension to the head device when adjusting the distance between the opening provided in the head device and the toner conveying member, and the head device is gradually deformed and the opening of the opening is reduced. Even if the position is not shifted, the shape of the openings and the pitch between the openings are not changed, and even if the molding accuracy and the mounting accuracy of the toner conveying member are poor, the above-described spacer is used as the toner conveying member. As a result, the distance between the opening and the toner conveying member is always kept constant, and a constant image is stably formed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an image forming apparatus according to an embodiment of the present invention will be specifically described with reference to the accompanying drawings.

In the image forming apparatus of this embodiment, as shown in FIGS. 1 and 2, a large number of circular openings 12 are provided in a head substrate 11 formed of a flexible resin sheet. And a head device 10 provided with a control electrode 13 for controlling toner ejection around each opening 12.
The toner t is supplied from the toner supply device 20 to the opening of the head device 10.

When the toner t is supplied from the toner supply device 20 to the opening 12 provided in the head device 10, the toner t is supplied to the toner supply device 20.
The toner transporting member 2 in which the toner t contained in the toner supply device 20 is formed into a roller by rotating the feeding member 21 provided in the toner supply device 20
2 and the toner transport member 22 is rotated to transport the toner t. Then, the regulating member 23 is brought into contact with the surface of the toner conveying member 22 for conveying the toner t in this way, and the regulating member 23 regulates the amount of the toner t conveyed by the toner conveying member 22 and charges the toner t. Then, the toner t charged in this way is guided to the opening 12 provided in the head device 10.

In the image forming apparatus according to this embodiment, one end of the head device 10 is attached to a support member 31, and the opening 12 provided in the head device 10 has a toner conveying member 22 and an axial direction. And a spacer 32 for adjusting the distance between the toner carrying member 22 and the opening 12 is attached to the surface facing the toner carrying member 22, while the surface opposite to the toner carrying member 22 is attached. The head device 10 is attached to the toner conveying member 2 by the elastic member 33.
2, the spacer 32 attached to the surface facing the toner conveying member 22 is brought into contact with the toner conveying member 22 so that the distance between the toner conveying member 22 and the opening 12 is maintained constant. I have to.

In the image forming apparatus according to this embodiment, the back electrode 41 is provided at a position opposite to the toner conveying member 22 via the head device 10 so as to face the head device 10 with a required space. The back electrode 41 is rotated, and a voltage having a polarity to attract the charged toner t from the power source 42 is applied to the back electrode 41, and the recording sheet 43 is placed between the back electrode 41 and the head device 10. I try to guide.

In the image forming apparatus according to this embodiment, the toner t charged by the toner conveying member 22 provided in the toner supply device 20 as described above is guided to the opening 12 provided in the head device 10. When the toner t is discharged from the opening 12 to form an image on the recording sheet 43, the back electrode 41 provided opposite to the head device 10 is rotated, and the back electrode 41 is supplied from the power source 42. While applying a voltage having a polarity to attract the charged toner t, the head device 10
Each control electrode 1 provided around each opening 12 in
3 is applied with an electric signal based on image information from the output device 44 so that the toner t is discharged from an appropriate opening 12.

When the toner t is negatively charged, the power supply 42 supplies the toner t to the back electrode 41.
Is applied to the control electrode 13 provided in the opening 12 where the toner t is not discharged from the output device 44 so that the toner t does not pass through the opening 12. , The negative voltage that repels the toner t is continuously applied to suppress the toner t from being introduced into the opening 12 while the opening 12 that discharges the toner t is used.
As shown in FIG. 3, an electric signal composed of a positive pulse voltage for attracting the toner t is applied to the control electrode 13 provided to the toner cell 12 to guide the toner t into the opening 12. In this way, the toner t guided into the opening 12 is attracted to the back electrode 41 and the opening 1
2 and is supplied to the recording sheet 43.

After the toner t is supplied to the recording sheet 43 and an image is formed on the recording sheet 43, the toner t supplied to the recording sheet 43 is fixed by a fixing device (not shown). To make it work.

Here, in the image forming apparatus of this embodiment, the head device 10 is moved toward the toner conveying member 22 by the elastic member 33 provided on the surface of the head device 10 opposite to the toner conveying member 22 as described above. Energized,
Since the spacer 32 provided on the surface facing the toner conveying member 22 is brought into contact with the toner conveying member 22, the toner conveying member 22 and the head device 10 can be used even when the molding accuracy and the mounting accuracy of the toner conveying member 22 are poor. Of the head device 10 is not constantly deformed by strong tension, the position of the opening 12 is shifted, and the shape of the opening 12 is not changed. The toner t is stably discharged through the openings 12 of the head device 10 in a constant state without changing the pitch between the openings 12 and the head device 10, and a stable image can be obtained for a long period of time.

In the image forming apparatus according to the embodiment of the present invention, when the toner t is charged in the toner supply device 20, the toner t conveyed by the toner conveying member 22 is regulated and charged by the regulating member 23. However, it is also possible to use a developer containing a toner and a carrier, and charge the toner by bringing the toner into contact with the carrier.

In the image forming apparatus of this embodiment, an image is formed by discharging the toner t onto the recording sheet 43 directly from the opening 12 of the head device 10. An intermediate transfer member (not shown) is guided between the intermediate transfer member and the back electrode 41, and a toner image is formed by discharging toner t from the opening 12 to the intermediate transfer member. It is also possible to transfer the toner image to the recording sheet 43.

[0023]

As described in detail above, in the image forming apparatus according to the present invention, the spacer is attached to the surface of the head device facing the toner conveying member, and the elastic member is attached to the opposite surface. The member urges the head device toward the toner conveying member to bring the spacer mounted on the surface facing the toner conveying member into contact with the toner conveying member, thereby opening the toner conveying member and the opening provided in the head device. It is not necessary to apply strong tension to the head device, and the head device is gradually deformed and the position of the opening is shifted, and the shape of the opening and the pitch between the openings are changed. The spacers come into contact with the toner conveying member and open even when the molding accuracy and the mounting accuracy of the toner conveying member are poor. Distance between parts and the toner conveying member is always to be kept at a constant state.

As a result, in the image forming apparatus of the present invention, the toner is stably discharged in a constant state through the opening of the head device, and a stable image can be obtained for a long period of time.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing a state in which an image is formed on a recording sheet by supplying toner from a toner supply device to a head device in an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic explanatory diagram showing a state in which an output device applies an electric signal based on image information to each control electrode provided around each opening in the head device in the image forming apparatus according to the embodiment; It is.

FIG. 3 is a diagram showing an electric signal applied to a control electrode when toner is ejected from an opening of the head device in the image forming apparatus according to the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Head apparatus 12 Opening 20 Toner supply device 22 Toner conveyance member 31 Support member 32 Spacer 33 Elastic member t Toner

Claims (1)

[Claims] 1. An image forming apparatus comprising: a sheet-like head device provided with an opening for discharging toner; and a toner supply device provided with a toner conveying member for guiding toner to the opening of the head device. In addition to holding one end of the head device so that the opening faces the toner conveying member, in the head device, the surface facing the toner conveying member contacts the toner conveying member to reduce the distance from the toner conveying member. An image forming apparatus comprising: a spacer to be adjusted; and an elastic member for urging the head device toward the toner conveying member is attached to a surface opposite to the toner conveying member.