JPH045666A - Recorder - Google Patents

Abstract

PURPOSE:To sufficiently carry out the flying of toner and to produce a sharp recorded image by setting the volume resistivity R of a developer carrier at 10<8=R<=10<10>OMEGAcm. CONSTITUTION:When a control signal output part 24 outputs a pulse signal, the voltage of a potential difference V1 + V2 is applied between an intermediate transfer medium 6 and a wire electrode 22, and the toner T flies to the medium 6 along a formed electric field. At this time, a charge having the reversed polarity equivalent to the total charge quantity of the flied toner T is left on a magnetic grain left on a film 21. When voltages V1 and V2 are set so that, for instance, the electric field of 10<8> V/cm is formed between the medium 6 and the electrode 22 via the film 21, the volume resistivity of the film 21 is almost 10<9>OMEGA.cm. Therefore, when the volume resistivity of the film 21 is low such as 10<9>.cm, a residual charge flows into a ground via the electrode 22 a power source 23, and is not stagnated. Thus, the toner enough to form one dot flies to the medium 6.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention particularly relates to a recording apparatus that records images on plain paper without using a photoreceptor.

[Prior Art] As one type of recording device that does not use a photoreceptor, for example, a spiral electrode formed in a spiral shape is provided on the surface of a sleeve that rotates at high speed, and a rotatable counter electrode is provided at a position opposite to this spiral electrode. By applying a pulse voltage according to a recording signal to the control electrode, the toner adhering to the film surface is flown to the counter electrode, and further A recording device has been devised that records toner attached to a counter electrode on paper.

The figures shown in FIGS. 6(a) to 6(e) show the state in which the toner on the surface of the film in the above-mentioned recording apparatus is made to fly to the above-mentioned counter electrode. In addition, in (a) to (e) of the same figure, 1
indicates the above-mentioned counter electrode, 2 indicates a spiral electrode, 3 indicates a film (developer transport body), and 3a and 3b indicate control electrodes disposed within the film 3.

Further, the counter electrode 1 is supplied with a predetermined voltage plus V2 from the power source 1a.
is applied, a predetermined voltage minus 1 is applied to the spiral electrode 2 from the power supply 2a, and a pulse voltage is applied to the control electrodes 3a and 3b from the control signal output section 4 at a predetermined timing. In addition, the switch S is switched to the terminal ■ side by the pulse signal output from the control signal output section 4, and the control electrode 3a
, 3b become the ground level, and when the pulse signal disappears, the switch S switches to the terminal ■ side, and the control electrodes 3a, 3b
A voltage of plus ■3 is applied to . Switching of the switch S is performed by an image data signal (not shown).

In the above-mentioned state, when the developer consisting of the toner T of negative polarity and the magnetic particles J of positive polarity is conveyed onto the film 3, first, it is transferred from the control signal output section 4 to the control electrode 3a.
, 3b, when the above-mentioned pulse signal is not output to the sixth
As shown in Figure (a), a voltage 3 is applied to the control electrodes 3a and 3b.

This voltage 3 has the same polarity as the voltage 2 applied to the counter electrode 1, so no electric field is formed, the toner T does not fly to the counter electrode 1, and the magnetic particles J are also controlled to the counter electrode 1. The potential difference between the electrodes 3a and 3b is V3-V2, which is weak, and there is not enough flying force to fly to the counter electrode 1 against the magnetic force from a magnet roll (not shown) provided below the spiral electrode 2.

Next, when a pulse signal is output from the control signal output section 4 as shown in FIG.
Based on the output voltages from a and 2a, the potential difference V, 10V
2, and an electric field Ed is formed between the counter electrode 1 and the spiral electrode 2. Therefore, the toner T flies toward the counter electrode 1 along this electric field Ed. At this time, charges of opposite polarity (positive charges) equal to the total amount of charge of the flying toner T are left on the magnetic particles J left on the film 3, and become accumulated charges on the film 3. Since the film 3 is composed of an insulating film and has a high volume resistance R of 10 13 to 10 I 5 Ω·cm, the charges accumulated in the film 3 cannot flow to the spiral electrode 2 . For this reason, the accumulated charge on the film 3 is
It acts to weaken the electric field Ed between the spiral electrode 2 and the spiral electrode 2. Therefore, the more the toner T flies to the counter electrode 1, the weaker the electric field Ed becomes, and eventually the toner T stops flying to the counter electrode 1 as shown in FIG.

FIG. 7 is a diagram showing the relationship between the output timing of the pulse signal of the control signal output section 4 and the electric field Ed generated between the counter electrode 1 and the spiral electrode 2, and the above description corresponds to the period T+. That is, when a pulse signal is output from the control signal output section 4, an electric field of minus E0 is generated, but as shown in the figure, the electric field decreases until an equilibrium state is reached due to the formation of the above-mentioned accumulated charges. That is, the toner T flies only during the period (T8) indicated by diagonal lines A, and the magnitude of the electric field Ed decreases to E0 to E+.

Next, when the output of the pulse signal from the control signal output section 4 is finished according to the image data, the voltage V3 is applied to the control electrodes 3a and 3b as shown in FIG. 6(d). At this time, since the above-mentioned accumulated charges remain in the film 3, an electric field having a magnitude El based on the accumulated charges is formed between the counter electrode 1 and the film 3 due to the accumulated charges. Therefore, as shown in FIG. 3(d), the magnetic particles J on the film 3 fly toward the counter electrode 1 by this electric field against the magnetic force from the magnet roll. Then, the amount of charge of the magnetic particles J flying from the film 3 cancels out the accumulated charge of the film 3, and finally the flying of the magnetic particles J to the counter electrode 1 stops.

Period T2 in FIG. 7 shows the change state of the electric field during the above-mentioned period.

That is, when the output of the pulse signal from the control signal output section 4 stops, an electric field of magnitude E+ is generated, but the magnetic particles J
As it flies, the electric field increases in magnitude B2 as shown in the figure.
decreases to Therefore, in this case, the magnetic particles J fly toward the counter electrode 1 only during the period B1 indicated by diagonal lines. In addition, the electric charge possessed by the magnetic particles J that flew to the counter electrode 1 is shown in Fig. 6 (
As shown in e), it flows to ground via the power supply 1a. For this reason, the magnetic particles J that once flew to the counter electrode 1 lose their charge and return onto the film 3 due to the magnetic force of the above-mentioned magnet roll.

Thereafter, in the conventional recording apparatus, the above-described process is repeated to cause the toner to fly to the counter electrode 1 and form a toner image on the counter electrode 1. Thereafter, the toner image formed on the counter electrode 1 is transferred to a sheet of paper to complete the creation of a recorded image.

[Problems with conventional technology]

In the conventional recording device, since the accumulated charge remains on the film 3 as described above, each period T, , T, as shown in FIG.
As shown in the figure, the electric field Ed formed between the counter electrode 1 and the spiral electrode 2 (film 3) in 2, . . . is the so-called critical electric field (! Eo
It will drop to E+ or E0E2 to E3. For this reason, the amount of toner that flies to the counter electrode 1 for each pulse signal output is not sufficient, and therefore the recorded image on the paper obtained by transferring the toner image on the counter electrode 1 is also pale and clear. Unable to obtain recorded images.

Further, although the magnetic particles J are also collected by the film 3, they once fly to the counter electrode 1. For this reason, the toner image formed on the counter electrode 1 is disturbed, and this adverse effect is particularly large in the case of a line-shaped recorded image.

[Purpose of the invention]

In view of the above-mentioned conventional problems, an object of the present invention is to provide a recording device that can generate a clear recorded image by sufficiently flying toner, and can also obtain a recorded image with excellent print quality. .

[Summary of the Invention] In order to achieve the above object, the present invention includes a developer transporting body that carries a developer made of a mixture of insulating non-magnetic toner and magnetic particles on its surface and transports the developer along a predetermined path; a helical electrode body rotatably disposed on the opposite side to the developer carrying surface of the developer carrying body and having linear electrodes spirally arranged on the circumferential surface; and a control electrode provided in the developer carrying body. and a cylindrical electrode rotatably disposed opposite to the spiral electrode body on the developer carrying surface side of the developer carrying member, and a pulse voltage is applied to the control electrode according to recorded information to remove the toner. In the recording apparatus having a pulse voltage applying means for causing the cylindrical electrode to fly, the volume resistance R of the developer transporting body is 108≦R≦
It is characterized by having a resistance of 1010 Ωcm.

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

FIG. 2 is a schematic cross-sectional view of a recording device according to an embodiment. In the figure, a recording device 5 includes an intermediate transfer medium 6, a developing device 7 for forming a toner image on the intermediate transfer medium 6, and a transfer device for transferring the toner image formed on the intermediate transfer medium 6 onto a sheet of paper. 8, a paper feed cassette 9 for storing paper, and a paper feed roller 9
', transport guide plates 10 and 11, transport roll] 6, and fixing roll 12. A claw 13 for separating paper from the intermediate transfer medium 6 and a cleaner 14 for removing toner remaining on the intermediate transfer medium 6 are provided near the circumferential surface of the intermediate transfer medium 6.

Further, the cleaner 14 is connected to the developing container 7' from the cleaner 14.
Recycling pipe 1 for reusing toner collected in
5 are arranged. The fixing roll 12 includes a heating roll 12a with a built-in heater and a pressure roll 12b.
This is a roll that fixes the unfixed toner image onto the paper while conveying the paper.

Further, the paper on which the toner image has been fixed by the fixing roll 12 is discharged to the tray 17.

The developing device 7 is constructed by disposing a developing roll 19 in a developing container 7', and further contains a developer consisting of non-magnetic insulating toner T and magnetic particles J inside the developing container 7'. At one end of the developer container 7', there is a blade 7 for regulating the N thickness of the toner layer adhering to a film (insulating film) which will be described later.
a is formed. The developing roll 19 includes a magnet roll 19b fixed to a rotating shaft 19a and a sleeve 19c fixed to the outer periphery of the magnet roll 19b. Further, the developing roll 19 is covered with a fixed sleeve 20 provided at a predetermined distance from the developing roll 19 and a film 21 stretched on both ends of the fixed sleeve 2o.

The rotating shaft 19a is configured to be rotatable at high speed in the direction of arrow a shown in the figure by a drive mechanism (not shown). Further, a spiral linear electrode 22 is embedded in the circumferential surface of the sleeve 19c. Note that the magnet roll 19b is connected to the developer container 7.
It functions to transport the developer inside ' by the circumferential surface of the fixed sleeve 20 and the film 210.

The intermediate transfer medium 6 is disposed directly above the developing roll 19, and is disposed at a position facing the film 21 with a predetermined interval therebetween. This intermediate transfer medium 6 is a cylindrical electrode body made of a metal tube, and rotates at a predetermined speed in the direction indicated by the arrow around an axis 6a. A blade 14a disposed in the cleaner 14 mentioned above is in contact with the circumferential surface of the intermediate transfer medium 6, and removes toner remaining on the circumferential surface of the intermediate transfer medium 6. Further, the aforementioned transfer device 8 is disposed facing the intermediate transfer medium 6 across the paper conveyance path, and a predetermined high voltage is applied to this transfer device 8 from a high voltage power source 8a.

FIG. 1 is a diagram showing the arrangement of the intermediate transfer medium 6, the sleeve 19c, and the film 21, and a schematic circuit structure. Linear electrode 2 embedded in the circumferential surface of the sleeve 19c
2 is connected to a power source 23, and the linear electrode 22 is connected to the power source 23.
A predetermined voltage (1) is applied to. Further, a predetermined voltage 2 is applied to the intermediate transfer medium 6 from a power source 6b connected to the rotating shaft 6a. The output voltage values of the power supplies 6b and 23 are voltage values that set the electric field applied to the film 21 to a predetermined value, as will be described in detail later.

As will be described later, the toner T and magnetic particles J on the film 21 shown in the figure are attached to the fixed sleeve 20 by the magnetic force of the magnet roll 19b as the magnet roll 19b rotates in the direction of the arrow a, and are moved in the direction of the arrow C. It has been conveyed over the fixed sleeve 20.

The film 21 has a thickness of 40 mm, for example, as shown in the figure.
The material is nylon 66. FIG. 3 shows the volume resistance characteristics of nylon 66 used for the film 21. Specifically, the intermediate transfer medium 6 and the linear electrode 2 are connected via a film 21 made of nylon 66.
The strength of the electric field Ed formed between the film 21 and the
shows the volume resistance characteristics of In addition, for comparison, Figure 3 shows PET
The volume resistance characteristics of (polyethylene terephthalate) are also shown.

Furthermore, control electrodes 21a and 21b are arranged within the film 21, and a control signal output section 24 is connected to each of the control electrodes 21a and 21b.

The control signal output section 24 outputs a positive voltage when not printing, and outputs a ground level pulse signal when printing according to image data (not shown).

Further, the layer thickness of the toner layer moving on the upper surface of the film 21 is set by the aforementioned blade 7a, and in this embodiment, the layer thickness is 40 mm.
It is μm. Further, the distance (gap G) between the upper surface of this toner layer and the intermediate transfer medium 6 is set to a predetermined gap.

Next, the operation of recording an image on paper by the recording device 5 having the above configuration will be described. In this embodiment as well, the toner T has a negative polarity, and the magnetic particles J have a positive polarity.

First, the rotational force of a motor (not shown) is applied to the intermediate transfer medium 6 described above.
When the image is transmitted to the rotating shafts 6a and 19a of the developing roll 19, the intermediate transfer medium 6 and the developing roll 19 start rotating. The toner T and magnetic particles j in the developing container 7' are attracted to the circumferential surface of the fixed sleeve 20 by the magnetic force of the magnet roll 16b, and as the developing roll 19 rotates in the direction of the arrow a, it moves on the fixed sleeve 20 in the direction of the arrow. It is transported in the C direction. The toner T and magnetic particles J conveyed on the fixed sleeve 20 are regulated to the above-mentioned constant layer thickness by the blade 7a, and are conveyed on the film 21 in the direction of arrow C as shown in FIG.

Here, from the control signal output section 24, the control electrodes 2 a, 21
The state where a positive voltage is applied to b is the same as the state shown in FIG. 6(a) in the conventional example.

That is, as shown in FIG. 4(a), the control electrodes 21a, 2
A voltage (3) is applied to 1b, and neither the toner T nor the magnetic particles J on the film 21 fly to the intermediate transfer medium 6.

Next, when a pulse signal is output from the control signal output section 24 as shown in (■) in the same figure, the control electrodes 21a and 21b are set to the ground level as in the case explained in the conventional example.
There is a potential difference V, +V2 between the intermediate transfer medium 6 and the linear electrode 22.
voltage is applied, and an electric field is formed between the linear electrode 19 and the intermediate transfer medium 2. Therefore, the toner T flies to the intermediate transfer medium 6 along the formed electric field. At this time, the magnetic particles J left on the film 21 are covered with flying toner T.
A charge of opposite polarity equal to the total charge of is left behind.

However, the film 21 used in this embodiment has the characteristics shown in FIG. 3 with respect to the electric field supplied as described above. Therefore, for example, at this time 108V/cm (
If the aforementioned voltages 1 and V2 are set so that a D electric field is formed between the intermediate transfer medium 6 and the linear electrode 22 through the film 21, the volume resistance of the film 21 becomes approximately 109Ω.
cm. Therefore, as shown in FIG. 4(b), if the volume resistance of the film 21 is as low as 10<9 >[Omega].1, the residual charge within the film 21 flows from the linear electrode 22 to the power supply 23 to the ground.

That is, unlike the conventional case, no accumulated charge remains in the film 21.

Therefore, the electric field formed between the intermediate transfer medium 6 and the linear electrode 22 is not weakened, and the electric field is maintained during the period T1 in FIG.
As shown in the figure, a constant electric field strength E0 is maintained during pulse voltage output. Therefore, during the period T1, the intermediate transfer medium 6 has 1
Enough toner is ejected to form a dot.

Next, when the pulse signal from the control signal output section 24 ends, the voltage 3 is applied to the control electrodes 21a and 21b again. Therefore, the electric field formed between the intermediate transfer medium 6 and the linear electrode 22 also disappears.

Furthermore, since there is no accumulated charge in the film 21 at this time, no electric field is formed based on the accumulated charge as in the conventional case. Therefore, the electric field becomes zero as shown in period T2 in FIG.

Next, when a pulse signal is outputted again in period T3 according to the image data, the control electrodes 21a and 21b become the ground level, resulting in the state shown in FIG. In order to maintain the intensity Eo, sufficient toner can be ejected to the intermediate transfer medium 6.

By repeating the above process every time a pulse signal is output, a clear toner image is formed on the circumferential surface of the intermediate transfer medium 6 in accordance with the image data.

Thereafter, as the intermediate transfer medium 6 rotates, the toner image formed on the circumferential surface of the intermediate transfer medium 6 as described above is transferred to the transfer device 8.
The voltage applied to the transfer device 8 at this time is a high voltage from the high voltage power supply 8a, which is higher than the voltage 2 applied to the intermediate transfer medium 6, so that the voltage is formed on the intermediate transfer medium 6. The toner T is attracted to the transfer device 8 side. Therefore, by feeding the paper between the intermediate transfer medium 6 and the transfer device 8 at this time, a clear toner image is transferred onto the paper.

Furthermore, since the magnetic particles J do not fly onto the intermediate transfer medium 6, there is no disturbance in the toner image formed on the circumferential surface of the intermediate transfer medium 6. Therefore, the quality of the image transferred onto the paper is excellent. The paper onto which the toner image has been transferred in this manner is thermally fixed by the above-mentioned fixing roll 12, and then discharged onto the tray 17.

As described above, in this embodiment, the film 21 is made of nylon 66 whose volume resistance is set in the range of 108≦R≦10I0Ω・an by applying a predetermined electric field Ed, and the toner T is prevented from flying. The accumulated charges remaining on the film 2 are grounded, the magnitude of the electric field Ed is kept constant during pulse voltage output, and a toner image with sufficient toner density is formed on the intermediate transfer medium 6.

In this example, the film 21 is made of nylon 66, but the volume resistance becomes 108≦R≦1 by supplying a predetermined electric field.
Any material that can be set within the range of 0I0Ω·cm can be similarly used.

(Effects of the Invention) As described above in detail, according to the present invention, the toner can be sufficiently ejected to the intermediate transfer medium, and the toner image formed on the intermediate transfer medium can be clearly recorded on the transferred paper. Images can be created.

Furthermore, since there is no flying of magnetic particles to the intermediate transfer medium, it is possible to obtain a recorded image with extremely high print quality without image disturbance.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the main parts of a recording device according to an embodiment, FIG. 2 is a diagram showing the overall configuration of a recording device according to an embodiment, FIG. 3 is a volume resistance characteristic diagram of the material used for the film, and FIG. a), [Yes]) are diagrams explaining the recording operation of the recording device of one embodiment, FIG. 5 is a characteristic diagram of the electric field Ed with respect to the pulse voltage of the recording device of one embodiment, and FIGS. e) is a diagram explaining the recording operation of the conventional recording device, and Fig. 7 shows the electric field Ed for the pulse voltage of the conventional recording device.
FIG. 5... Recording device, 6... Intermediate transfer medium, 6b, 23... Power source, 7... Developing device, 8... Transfer device, 9... Paper feed cassette, 12... Fixing Roll, 19... Developing roll, 19b... Magnet roll, 19c... Developing sleeve, 20... Fixed sleeve, 21, 22, 24, T, J, film, linear electrode, control signal output section , toner, magnetic particles.

Claims (1)

[Claims] A developer transporting member that carries a developer made of a mixture of insulated non-magnetic toner and magnetic particles on its surface and transports the developer along a predetermined path, and a side opposite to the developer carrying surface of the developer transporting member. a helical electrode body rotatably disposed on the circumferential surface thereof and having linear electrodes arranged in a spiral manner; a control electrode provided within the developer transport body; a cylindrical electrode rotatably arranged opposite to the helical electrode body;
In a recording apparatus having a pulse voltage applying means for applying a pulse voltage to the control electrode according to recording information to cause the toner to fly to the cylindrical electrode, the volume resistance R of the developer conveying body is set such that 10^8≦R≦ A recording device characterized in that the resistance is 10^1^0Ω·cm.