JPH06262796A - Image recorder - Google Patents

Abstract

PURPOSE:To provide an image recorder in which toner can be uniformly supplied to all openings, a high speed printing is performed with fast response, and omission of a pixel due to clogging of the opening is eliminated. CONSTITUTION:Toner 26 carried on a toner carrying roller 22 is conveyed in contact with an aperture electrode 1. Since the electrode 1 is supported through an electrode support 12 made of elastomer such as rubber, etc., its tension is uniform and stable toner supply-image output can be performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus having an opening and having means for modulating and controlling the flow of the charged toner passing through the opening, and more particularly to a copying machine, a printer, a plotter, a facsimile. The present invention relates to an image recording device applied to the above.

[0002]

2. Description of the Related Art Conventionally, an electrode (aperture electrode) having an opening is used as a toner flow control means, and an image signal is applied to the electrode to control passage of toner particles through the opening so that the toner particles can be formed on the counter electrode. An image recording apparatus for obtaining an image on a support arranged has been proposed, for example, US Pat.
89,935 specification, etc. In this method, a shield electrode that is continuous on one side with a layer of an insulator interposed between the shield electrode and a plurality of control electrodes that are insulated from each other on the other side are formed, and three layers are penetrated by each insulated control electrode. And an aperture electrode having openings arranged in at least one row, a means for selectively applying a potential between the control electrode and the shield electrode, and a flow of toner particles through the openings by the applied potential. And a means for moving the support relative to the aperture electrode so as to position the support in the particle flow path.

In this system, for example, US Pat. No. 4,
743,926, 4,814,796, 4,780,733, and 4,75.
In the image recording apparatus described in Japanese Patent No. 5,837, the aperture electrode is arranged so that its control electrode is located on the support side and the shield electrode is located on the toner supply side.

On the other hand, in JP-A-2-226261, the aperture electrode is applied to the control electrode by disposing the shield electrode so that the shield electrode is located on the support side and the control electrode is located on the toner supply side. It has been shown that the efficiency of the applied voltage is about four times higher when off.

[0005]

However, in the above-mentioned method, the toner is generated by suspending it in the air like a fog or a cloud (this state is called a cloud-shaped toner, or simply a toner cloud), Since this is a method of supplying this to the vicinity of the opening, the following problems occur.

At the time of printing off, it is necessary to generate an electric field in the opening so as not to pass through the opening so that the toner does not pass through the opening. Voltages of the same polarity are applied.
As a result, the cloud-shaped toner moves away from the vicinity of the opening, so that the print-off efficiency can be increased.
In exchange, at the moment of print-on that follows print-off,
Since the toner cloud density in the vicinity of the opening is extremely low, the responsiveness at the time of ON after the OFF is extremely poor, and the image density becomes light only at the rising part of the print ON, resulting in uneven density. The problem of being lost has arisen.

Further, the cloud-shaped toner adheres to the control electrode due to an electrostatic image force or the like to block the opening, resulting in a problem that printing cannot be performed.

The present invention has been made in order to solve the above-mentioned problems, and it is possible to uniformly and uniformly supply toner to all the opening portions, the response is fast, and high-speed printing is possible. It is an object of the present invention to provide an image recording device that does not cause pixel omission due to clogging.

[0009]

To achieve this object, the image recording apparatus of the present invention supplies at least toner flow control means for modulating and controlling the toner flow and charged toner to this toner flow control means. An image recording apparatus comprising: a toner supply unit including at least a toner supply member for that purpose; and a counter electrode facing the toner flow control unit and arranged on the opposite side of the toner supply unit. At least one of the toner flow control means and the toner supply member is elastically supported by the housing so as to make elastic contact with the other via the toner.

[0010]

In the image recording apparatus of the present invention having the above construction, the toner flow control means and the toner supply means are elastically supported by the housing so that at least one of them makes elastic contact with the other. Therefore, due to the elastic action, the gap and pressure of the pressure contact portion between the toner flow control means and the toner supply means are made uniform regardless of the position, and at the same time, wrinkles due to pressure unevenness do not occur in the toner flow control means. Therefore, the toner is supplied in good condition to the toner flow control means while being conveyed in contact with the toner flow control means.

Further, since the distance between the toner flow control means and the toner carrier is via the toner, the distance can be always constant without using a complicated mechanism.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of the image recording apparatus of the embodiment. In FIG. 1, a rear electrode roller 32 is rotatably supported on the frame of the apparatus above the aperture electrode 1 as a toner flow control means with a space of 1 mm.
As a result, the support 31 is conveyed as the back electrode roller 32 rotates. Below the aperture electrode 1,
A toner supply device 20 is provided. A fixing device 35 is disposed at the destination of the support 31.

The toner supply device 20 is constructed as follows.

In the toner case 21, together with the toner 26, a supply roller 23 and a toner carrying roller 22 are arranged in parallel and are rotatably held. The toner carrying roller 22 is configured by adhering a nickel sleeve 25 having a thickness of 20 μm around a sponge roller 24. The sleeve 25 is electrically grounded. The toner 26 has an average particle size of about 10 μm.
The non-magnetic one-component insulating toner is used, and ordinary fluidizing agents and charge control agents are externally added.

The toner regulating blade 27 is arranged so as to come into pressure contact with the sleeve 25 on the toner carrying roller 22.

As shown in detail in FIG. 2, the aperture electrode 1 has at least one row of openings 6 having a diameter of 120 μm formed in an insulating sheet 2 made of polyimide having a thickness of 30 μm so as to surround each opening 6. A control electrode 3 is disposed on one side of the insulating sheet 2.

The aperture electrode 1 is arranged so that the control electrode 3 faces the back electrode roller 32 as shown in FIG.

A control voltage applying circuit 8 is connected between the control electrode 3 and the sleeve 25. The control voltage applying circuit 8 is + 25V or -10V based on the image signal.
Is configured to output. The back electrode roller 3
A DC power supply 33 capable of outputting a voltage of +1 kV is connected between 2 and the sleeve 25.

The aperture electrode 1 is fixed to a part of the toner case 21 via an electrode support 12 made of an elastomer such as rubber. Further, the toner carrying roller 22 is installed in the toner case 21 while being pressed against the aperture electrode 1 fixed as described above so that the electrode support 12 extends sufficiently against its own elastic action. ing. At this time, the pressure contact pressure between the aperture electrode 1 and the toner carrying roller 22 is constant regardless of the location due to the expansion and contraction of the electrode support 12.

The operation of the above structure will be described in detail below.

By rotating the toner carrying roller 22 and the supplying roller 23 in the direction of the arrow, the toner 26 is rubbed from the supplying roller 23 to the sleeve 25 of the toner carrying roller 22, is negatively charged, and is carried on the sleeve. It The carried toner 26 is thinned by the layer regulation blade 27 and is conveyed toward the vicinity of the aperture electrode by the rotation of the toner carrying roller 22.

Here, the toner on the sleeve is supplied directly below the opening 6 while being rubbed by the aperture electrode 1, and the sleeve 25 and the aperture electrode 1 are separated by this toner layer.
The toner particles 26 are separated by an average particle diameter of about 10 μm.

The toner 26 carried on the sleeve 25 is
Usually, fluidity is imparted by a method such as external addition of a fluidizing agent, and the fluidity is given between the aperture electrode 1 and the sleeve 25 and rolled and conveyed right below the opening 6. At this time, the frictional resistance between the aperture electrode 1 and the sleeve 25 is constant because the pressure contact pressure is uniform regardless of the location as described above, and therefore unnecessary vibration occurs when sliding with the aperture electrode 1 and the sleeve 25. It is possible to suppress the power consumption of the motor or the like for driving the sleeve 25 without causing the generation, and to prolong the life of the sleeve 25 and the aperture electrode 1 due to wear and damage.

Since the toner 26 also has a substantially uniform particle diameter, the gap distance between the aperture electrode 1 and the sleeve 25 can be made constant without using a complicated mechanism, and can be made smooth. Since the toner 6 is circulated and supplied in the vicinity of the opening 6, the toner 6 clogged in the opening 6
Can be scraped off by the toner 6 which is circulated and supplied, whereby the toner clogging is eliminated and there is no pixel omission due to clogging of the opening, and noise due to erroneous passage of the opening in the no signal state due to toner scattering is generated. It is possible to prevent the occurrence and unevenness of the toner supply amount.

Here, the control voltage 3 is applied to the control electrode 3 corresponding to the image portion in accordance with the image signal by the control voltage applying circuit 8.
Is applied. As a result, near the opening 6 corresponding to the image portion, a line of electric force is formed from the back electrode 32 side of the opening 6 toward the sleeve 25 side due to the potential difference between the back electrode 32 and the sleeve 25. The negatively charged toner 26 receives an electrostatic force in the direction of high potential, is drawn out from the sleeve 25, passes through the opening 6, and is deposited on the support 31 to form a pixel.

The control voltage applying circuit 8 applies -10 V to the control electrode 3 corresponding to the non-image area. As a result, in the vicinity of the opening 6 corresponding to the non-image area, the control electrode 3 is
An electric force line from the sleeve 25 to the control electrode 3 is formed by the potential difference between the sleeve 25 and the sleeve 25. Since the potential between the sleeve 25 and the control electrode 3 is lowered from the sleeve 25 to the control electrode 3 side, the toner 26 charged negatively
Does not pass through the opening 6.

The support 31 is fed by one pixel in the direction perpendicular to the row of the openings 6 during the pixel formation time of one row. Support 31
The image can be formed on the entire surface of the support 31 by the toner 26 by repeating the above process while the sheet is conveyed by the length.

In the above process, the toner 26 is always supplied in contact with the aperture electrode 1, so that the responsiveness is fast. Further, since the control electric field by the control electrode 3 is formed between the control electrode 3 and the sleeve 25 which are close to each other, it can be controlled with a low control voltage.

Further, since the toner 26 slides on the control electrode 3 of the aperture electrode 1, the toner is not deposited on the control electrode 3 and does not block the opening 6.

The present invention is not limited to the embodiments described in detail above, and various modifications can be made without departing from the spirit of the invention.

For example, in the above embodiment, only the aperture electrode, which is the toner flow control means, is elastically supported with respect to the toner case, which is the casing, but instead, the toner carrying roller, which is the toner supply member, is used. May be elastically supported on the toner case, or both may be elastically supported.

FIG. 3 shows an example in which the aperture electrode is fixed to the toner case and the toner carrying roller is elastically supported. Supporting roller support mechanism 4 in FIG.
For 0, a piston such as hydraulic pressure or pneumatic pressure, a spring, or the like can be used.

FIG. 4 shows an example in which both the aperture electrode and the toner carrying roller are elastically supported with respect to the toner case.

Further, in the above-mentioned embodiment, the structure of the aperture electrode is such that the control electrode 3 is only attached to one side thereof, but as shown in FIG. 5, the electric field formed by the back electrode 32 is a sleeve. A shield electrode 4 for shielding the electric field so as to prevent the action on the toner other than directly below the opening 6 above 25 may be provided on the back surface of the surface on which the control electrode 3 is provided. An example of an image recording device using such an aperture electrode is shown in FIG.

Incidentally, in FIGS. 1 to 6, the components having the same reference numerals have the same functions.

Further, in the above embodiment, the toner carrying roller 22 which is the toner carrying member is composed of the sleeve 25 and the sponge roller 24, but it is not limited to such a structure. For example, the sleeve may be made of nickel, copper, aluminum, other metal such as Ni-Ti alloy, or a known conductive resin, and the toner carrying roller itself is made of a cylindrical member made of these materials. It may have been done. The surface may be smooth, or the roughness may be adjusted according to the particle size of toner, the amount of charge, and the amount of toner carried.

[0038]

As is apparent from the above description, according to the image recording apparatus of the present invention, the toner can be uniformly supplied to all the openings, the response is fast and the high speed printing is possible, and the toner is It is possible to provide an image recording apparatus in which no pixels are missing due to clogging of the opening and unnecessary vibration and electrode damage are prevented.

[Brief description of drawings]

FIG. 1 is a sectional view showing the configuration of a first embodiment of an image recording apparatus of the present invention.

FIG. 2 is a perspective view showing details of an aperture electrode used in the first embodiment.

FIG. 3 is a sectional view showing a configuration of a second embodiment of the image recording apparatus of the present invention.

FIG. 4 is a sectional view showing the configuration of a third embodiment of the image forming apparatus of the present invention.

FIG. 5 is a perspective view showing details of an aperture electrode used in a fourth embodiment of the present invention.

FIG. 6 is a sectional view showing a configuration of a fourth embodiment of the image recording apparatus of the present invention.

[Explanation of symbols]

 1 Aperture Electrode 3 Control Electrode 6 Opening 8 Control Voltage Application Circuit 12 Electrode Support 21 Toner Case 22 Toner Carrying Roller 26 Toner 32 Back Electrode Roller 33 DC Power Supply 40 Carrying Roller Support Mechanism

Claims (1)

[Claims] 1. A toner flow control means for modulating and controlling at least a toner flow, a toner supply means including at least a toner supply member for supplying charged toner to the toner flow control means, and the toner flow control. In an image recording apparatus composed of a counter electrode arranged on the opposite side of the toner supply means opposite to the means, at least one of the toner flow control means and the toner supply member is the other. An image forming apparatus, which is elastically supported by a housing so as to be elastically contacted with respect to the toner.