JPH0444063A - Cleaning method for image forming device - Google Patents

Abstract

PURPOSE:To surely remove toner sticking in toner passing holes from the toner passing holes and to form an image of high picture quality by causing ultrasonic wave vibration by a toner control means when image forming operation stops. CONSTITUTION:The respective toner passing holes are cleaned for a specific time after a main switch is turned on. In this cleaning operation, a vibration magnitude varying means 41 adjusts the magnification of the ultrasonic wave vibration given to the insulating substrate 31 of the toner control means 30 from an ultrasonic wave vibration generating means 40 to larger than in normal image forming operation, and then the ultrasonic wave vibration generating means 40 is driven. The toner sticking in the respective toner passing holes 31a is separated from the respective toner passing holes 31a. Consequently, the toner sticking in the respective toner passing holes can be removed and the picture quality is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of cleaning an image forming apparatus using powder toner.

(Prior Art) Image forming methods using inkjet printers are known for word processors, facsimile machines, computers, and the like.

An inkjet printer is a typical so-called non-impact printer, which applies pressure to a predetermined liquid ink while applying ultrasonic vibrations using a piezoelectric element, etc.
A recorded image is formed on the recording paper by ejecting the liquid ink from an ink nozzle within a predetermined electric field, and controlling the ink particles by the electric field so that they adhere to the recording paper. Such an inkjet printer method has the advantage that it does not generate noise when forming an image and can form a clear image. On the other hand, in order to control the speed at which the ink soaks into the recording paper, it is necessary to use special paper with a surface treatment, etc., and since the ink is supplied from a nozzle, the nozzle can detect foreign particles in the ink. There is a problem that it is easy to get clogged due to such things.

In order to solve such problems with inkjet printers, an image forming apparatus using powder toner as an image recording medium is disclosed in, for example, Japanese Patent Application Laid-Open No. 60-263962. This image forming apparatus uses powder toner particles to
A toner control means is provided in the pinhole-shaped toner passage hole to control the passage of the toner by an electrostatic attraction force generated in response to an image output signal, and the toner control means selects toner particles onto the recording paper. A predetermined recorded image is formed on the recording paper. In such devices, plain paper without surface treatment can be used as the recording paper, and furthermore, since fine powder toner is used, toner clogging in each toner passage hole is suppressed. .

A toner control means for controlling powder toner includes an insulating substrate provided with a large number of pinhole-shaped toner passage holes, and a toner control means provided between the insulating substrate so as to form an electric field in each toner passage hole. It has a pair of electrodes. Each pair of electrodes is provided with a pinhole-like through hole of the same size as each toner passage hole, and each through hole is provided on one side of each insulating substrate. Installed in a consistent manner.

Then, by applying a predetermined voltage between both electrodes to form an electric field in a predetermined direction within the toner passage hole, the toner particles are passed through the toner passage hole.

When toner particles are not allowed to pass through the toner passage hole, a predetermined voltage is applied between each electrode so that an electric field is formed in the toner passage hole in the opposite direction to that when the toner passes through the toner passage hole. Ru.

Further, a base electrode is disposed on the recording paper arrangement side, which is the toner passing direction side of the toner control means, and the recording paper is disposed on the base electrode.

A predetermined potential difference is provided between the base electrode and the toner supply side electrode of the toner control means, and an electric field is created so that the toner can reliably move toward the recording paper.

In such an image forming apparatus, dots are formed by toner passing through each toner passage hole, and an image such as a character is formed by a collection of the dots.

(Problem to be Solved by the Invention) In such an image forming apparatus, if image forming operation is performed for a long period of time, toner may adhere to the pinhole-shaped toner passage hole and the toner passage hole may be clogged with toner. be. If the toner passage hole is clogged with toner, the image quality will be significantly degraded, such as white spots appearing on the image formed on the recording paper.

The present invention solves the above-mentioned conventional problems, and an object thereof is to provide a method for cleaning an image forming machine that can reliably remove toner adhering to toner passage holes.

(Means for Solving the Problems) A method for cleaning an image forming apparatus according to the present invention includes an insulating substrate provided with a toner passage hole, and the insulating substrate being sandwiched between the insulating substrates so as to form an electric field in the toner passage hole. a toner control means having a pair of electrodes formed with a through hole communicating with the toner passage hole; and at least a direction in which the toner passes through the toner passage hole according to image information. an image information generating means for controlling the electric potential between the pair of electrodes of the toner controlling means so as to form an electric field; and an ultrasonic vibration generating means for applying vibration to the toner controlling means; The image forming apparatus is characterized in that when the image forming operation is stopped, the ultrasonic vibration generating means is operated in order to remove the toner in the toner passage hole, thereby achieving the above-mentioned effect. The purpose is achieved.

(Function) In the method for cleaning an image forming apparatus of the present invention, when the ultrasonic vibration generating means is operated when the image forming operation is stopped, the toner control means is ultrasonically vibrated and the toner passes through the toner passage hole. The attached toner is removed from the toner passage hole, and the toner inside the toner passage hole is reliably removed.

one (Example) Hereinafter, the present invention will be described with reference to examples.

The cleaning method of the present invention is carried out by the image forming apparatus shown in FIG. The image forming apparatus includes a toner container 10 containing powder toner. The upper part of the toner storage container 10 communicates with a toner storage section such as a toner hopper, and the toner storage container 10 is sequentially replenished with toner. An opening 11 is provided at the bottom of the space in the toner storage container 10 in which the toner is stored.
Inside the opening 11, the upper part of a toner supply roller 20 serving as toner supply means is fitted. The toner contained in the toner storage container 10 is supplied to the toner supply roller 20.
is sequentially supplied downward by the rotation of .

Below the toner supply roller 20, a toner control means 30 is provided.
is provided in close proximity to the toner supply roller 20. The toner control means 30 includes an image information generation means 50.
The image signal is given by The image information generating means 50 is
It operates in response to signals from a device such as a word processor, facsimile, computer, etc., and generates electrical signals in accordance with image information.

According to this electric signal, the powder toner fed from the toner supply roller 2o is controlled by the toner control means 3o, and a predetermined toner image is formed on the recording paper 70.

The toner control means 3o may be in pressure contact with the toner supply roller 20.

The toner control means 30 is provided with an ultrasonic vibration generating means 40 that applies ultrasonic vibration, and a base electrode 60 is provided below the toner control means 30 facing the toner control means 3°. It is being

A recording paper 70 on which a toner image is formed on the base electrode 60
is placed. The base electrode 6o may be moved in the direction of arrow A together with the recording paper placed thereon, or the base electrode 6o may be fixed and only the recording paper 70 may be moved by the recording paper transport means. good. When a predetermined toner image is formed on the recording paper 70 by the toner control means 30, the recording paper 70 is conveyed to a predetermined fixing device (not shown), and the toner image is fixed to the recording paper 70 by the fixing device. will be established.

The toner control means 30 has a horizontal insulating substrate 31, as shown in FIG. The insulating substrate 31 has a large number of pinhole-shaped toner passage holes 31 penetrating in the vertical direction.
a are arranged in a direction perpendicular to the plane of the paper. Further, an ultrasonic vibration generating means 40 is disposed on the insulating substrate 31, and ultrasonic vibrations are applied to the insulating substrate 31 from the ultrasonic vibration generating means 401. The ultrasonic vibration generating means 40 is provided with a vibration intensity changing means 41 for changing the intensity of the generated ultrasonic vibration. The vibration intensity changing means 41 is adjusted when changing the image density to be formed, and for example, changes the voltage applied to the ultrasonic vibration generating means 40 to generate the ultrasonic vibrations generated by the ultrasonic vibration generating means 40. Change the amplitude of ultrasonic vibrations. Note that the vibration intensity changing means 41 may change the intensity of the generated ultrasonic vibrations by changing the frequency of the alternating current for driving the ultrasonic vibration generating means 40.

A common electrode 35 is provided on the upper surface of the insulating substrate 31, corresponding to each pinhole-shaped toner passage hole 31a. The common electrode 35 has a pinhole-shaped through hole 35a that penetrates in the vertical direction and has the same diameter as each toner passage hole 31a.
are provided, and each common electrode 35 is attached to the insulating substrate 31, with each through hole 35a aligned and communicating with the toner passage hole 31a of the insulating substrate 31. Further, on the lower side of the insulating substrate 31, signal electrodes 33 are provided corresponding to each toner passage hole 31a. Each signal electrode 33 also has an insulating substrate 3
A through hole 33a having the same diameter as each through hole 31a of 1 is provided, and each signal electrode 33 is attached to the insulating substrate 31.

The common substrate 35 on the insulating substrate 31 is grounded,
Further, an image information generating means 5o is connected to each signal electrode 33 provided on the insulating substrate 31, and an image signal as a voltage signal is input from the image information generating means 50 to each signal electrode 33. ing. As a result, the voltage applied to each toner passage hole 31a can be adjusted. Each signal electrode 33 is given a predetermined positive potential and negative potential depending on the image information. For example, in the case of information for which an image should be formed, a voltage of +100V is applied, and for non-image information that does not need to be formed, a voltage of +100V is applied. In the case of image information, it is controlled so that a voltage of -100V is applied.

The toner passing through the toner passage hole 31a in the toner control means 30 is formed by a common electrode 35 on the toner supply side of the toner control means 3o and a base electrode 60 provided on the toner passage side of the toner control means 3o. Due to the electric field generated, the recording paper 7 placed on the base electrode 6o
0. A predetermined bias voltage is applied to the base electrode 60.

An image forming apparatus method using an image forming apparatus having such a configuration will be described.

When the toner supply roller 20 rotates, the toner storage container 1
0 toner is supplied onto the common electrode 35 of the toner control means 30. The common electrode 35 is connected to the insulating substrate 3 by ultrasonic vibration generating means 40 provided on the insulating substrate 31.
Since ultrasonic vibration of constant amplitude is applied through 1,
The toner mass on the common electrode 35 is crushed as appropriate and falls from the through hole 35a of the common electrode 35 into the toner passage hole 31a of the insulating substrate 31.

The toner particles that have fallen into the toner passage hole 31a of the insulating substrate 31 are controlled according to the image signal applied to the signal electrode 33, and fall onto the recording paper 70 or are returned onto the common electrode 35.

For example, when a positive voltage is applied to the signal electrode 33 by the image signal generating means 50, an electric field is generated in the toner passage hole 31a from the signal electrode 33 toward the common electrode 35. Due to this electric field, toner particles that are negatively charged in advance are
It is attracted to the signal electrode 33, passes through the signal electrode 33, and is supplied onto the recording paper 70 on the base electrode 60. Since a positive bias voltage is applied to the base electrode 60 with respect to the common electrode 35, the electric field formed by the base electrode 60 and the common electrode 35 causes the toner passage hole 31 to be
The supply of toner particles from a is promoted. The toner that has passed through the toner passage hole 31a falls along the lines of electric force of the electric field.

The bias voltage applied to the base electrode 60 is sufficiently larger than the electric signal applied to the signal electrode 33, and is in the range of 300 to 1000 V in the case of negatively charged toner. If the bias voltage is lower than 300V, the force for concentrating the toner at the axial center position of the toner passage hole 3La will be weak, resulting in the formation of large dots on the recording paper.

As a result, the image formed on the recording paper 70 may be distorted. On the other hand, if the bias voltage is greater than 1.0 OOV, there is a risk that discharge will occur.

A non-image signal is given by the image information generating means 50,
When a negative voltage is applied to the signal electrode 33, an electric field is formed in the toner passage hole 31a from the upper common electrode 35 toward the lower signal electrode 33, and the negatively charged toner is returned to the common electrode 35. It will be done.

In such an image forming apparatus, toner may adhere to each pin-pole-shaped toner passage hole 31a, and each toner passage hole 31a may be clogged with toner. For this reason, when the image forming operation is stopped, for example, for a predetermined period of time after the main switch of the image forming apparatus is turned on until the image forming operation becomes possible, or for a predetermined period of time after the main switch is turned off, A cleaning operation is performed for each toner passage hole over time.

This cleaning operation is performed by the vibration intensity changing means 41 so that the intensity of the ultrasonic vibrations applied from the ultrasonic vibration generating means 40 to the insulating substrate 31 in the toner control means 30 is stronger than that during normal image forming operation. is adjusted, and then the ultrasonic vibration generating means 40 is driven. The ultrasonic vibrations generated by the ultrasonic generating means 40 vibrate the insulating substrate 31, so that the toner adhering to each toner passage hole 31a is released from each toner passage hole 31a. When such a state occurs, the image information generating means 50 applies a negative voltage similar to the image non-forming signal to the signal electrode 33. As a result, the toner passage hole 31
The toner separated from the toner a is returned to the toner supply roller 20 side, and the toner adhering to the toner passage hole 31a is removed from the toner passage hole 31a.

In this embodiment, during the image forming operation, the toner control means is vibrated by =13 ultrasonic vibration generation means. It may be used only to remove toner etc.

(Effects of the Invention) As described above, in the image forming apparatus cleaning method of the present invention, when the image forming operation is stopped, the toner control means is ultrasonically vibrated, so that no amount of particles is deposited in the toner passage hole. The toner can be reliably removed from the toner passage hole. Therefore, the image forming apparatus can form high-quality images.

4. FIG. 1 is a block diagram showing an example of an image forming apparatus in which the cleaning method of the present invention is implemented, and FIG. 2 is a block diagram of the main parts thereof.

IO... Toner storage container, 20... Toner supply roller, 30... Toner control means, 31... Insulating substrate, 31a... Toner passage hole, 33... Signal electrode, 35
... Common electrode, 40 ... Ultrasonic signal generating means, 41
... Vibration intensity changing means, 50... Image information generating means.

Claims (1)

[Claims] 1. An insulating substrate provided with a toner passage hole, and a through hole communicating with the toner passage hole sandwiching the insulating substrate so as to form an electric field within the toner passage hole. a toner control means having a pair of electrodes provided in a formed state; and a toner control means configured to form an electric field in at least a direction in which the toner passes in the toner passage hole according to image information. An image forming apparatus comprising: an image information generating means for controlling a potential between a pair of electrodes; and an ultrasonic vibration generating means provided to apply vibration to the toner controlling means, wherein an image forming operation is performed. A method for cleaning an image forming apparatus, characterized in that when the image forming apparatus is stopped, the ultrasonic vibration generating means is operated to remove toner in the toner passage hole.