JPH03219268A - Electrostatic recording device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a recording device, particularly an electrostatic recording device that directly records a toner image on plain paper. [Prior Art] No photoreceptor is used. As one of the recording devices, a linear electrode formed in a spiral shape is provided on the surface of a sleeve that rotates at high speed, and a movable cylindrical electrode is provided at a position opposite to this linear electrode, and a control electrode is formed inside between them. A toner image can be directly printed on the paper using the toner adhered to the surface of the film by disposing the film and applying a pulsed high voltage to the control electrode while holding and conveying the paper.
Therefore, electrostatic recording devices for obtaining recorded images have been devised.

In such an electrostatic recording device, the control electrode formed within the film is formed parallel to the axial direction of the two cylindrical electrodes. Then, an electric field based on the voltage applied between the linear electrode and the cylindrical electrode is formed through the gap provided in the control electrode, and the toner on the film is attracted to the paper.

[Problems with conventional technology]

In the electrostatic recording device configured as described above, the control electrode is arranged parallel to the axial direction of the cylindrical electrode. However, printing one line on paper involves sequentially printing a plurality of dots, and during this time the paper moves in the sub-scanning direction orthogonal to the main scanning direction. Therefore, the image printed on the paper is tilted at a predetermined angle. This is especially noticeable when printing in a line, and the print quality deteriorates.

[Purpose of the invention]

SUMMARY OF THE INVENTION In view of the above-mentioned conventional drawbacks, it is an object of the present invention to provide an electrostatic recording device that can prevent tilting of printed images and improve image quality.

[Key points of the invention]

In order to achieve the above object, the present invention includes a toner conveying body that carries toner on its surface, and a spiral electric bridge on the circumferential surface of the toner conveying body, which is rotatably disposed on the opposite side to the toner conveying surface of the toner conveying body. a control electrode disposed between the toner conveying surface of the toner conveying body and the helical electrode body; and a cylindrical electrode disposed facing the toner conveying surface of the toner conveying body. an electrostatic recording device that transfers the toner on the toner conveying body to a sheet of paper conveyed between the cylindrical electrode and the toner conveying body by applying a signal voltage according to print information to the control electrode. In the above, the control electrode is composed of a plurality of divided resistors inclined at an angle θ with respect to the axial direction of the cylindrical electrode, and the θ angle is t,,lθw=( K-cotθ
5r)-' (where K is any integer).

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 2 is a schematic cross-sectional view of an electrostatic recording device according to an embodiment. In the figure, an electrostatic recording device 1 includes a developing device 2 for printing images on paper, a cylindrical electrode body 3, a paper feed cassette 4 for supplying/transporting paper, a paper feed roller 5, and a standby unit. It is composed of a roll 6, a static elimination brush 7, a conveyance guide plate 8, a conveyance belt 9, and a fixing roll IO. The standby roll 6 has a heater (not shown) inside, and is a roll that transports the paper in the direction of arrow a at a predetermined timing and removes moisture contained in the paper. The static elimination brush 7 is a brush that removes static charges that are generated during paper conveyance. The conveyance guide plate 8 is a member that guides the conveyance when conveying the paper in the direction of arrow a, and is made of an insulating material. The conveyance belt 8 is a so-called air suction belt that rotates in the direction indicated by the arrow and conveys the paper having toner adhered to the underside while sucking it upward as will be described later. The fixing roll 10 is composed of a heating roll with a built-in heater and a pressure roll, and is a roll that fixes an unfixed toner image onto a sheet of paper. Incidentally, a tray 11 is formed on the side surface of the electrostatic recording apparatus 1, into which a sheet of paper having a toner image thermally fixed thereon is discharged.

The developing device 2 has a developing roll 12 in a developing container 2', and a negative polarity one-component highly magnetic toner T is stored in the developing container 2'. Further, a blade 2a is formed at one end of the developer container 2' to regulate the thickness of the toner layer adhering to a film (insulating film) to be described later. The developing roll 12 is composed of a magnet roll 12b fixed to a rotating shaft 12a, and a sleeve 12c fixed to the outer periphery of the magnet roll 12b.A fixed sleeve is provided at a predetermined distance from the sleeve 12c. 13 and a film 14 stretched over both ends of the fixing sleeve 13.

The rotating shaft 12a is rotated at high speed in the direction of arrow C shown in the drawing by a drive mechanism (not shown), and the toner is conveyed in the opposite direction of arrow a. Furthermore, a spiral linear electrode 17 is embedded in the circumferential surface of the sleeve 12c, as will be described later. still,
The magnet roll 12b functions to adsorb and transport the toner T in the developer container 2' onto the circumferential surface of the toner transport body 13.

The cylindrical electrode body 3 is disposed directly above the developing roll 12,
It is arranged at a position facing the film 14 with a predetermined interval therebetween.

Figure 3 shows the cylindrical electrode body 3, the developing section 12, and the film 1.
FIG. 4 is a perspective view showing the arrangement configuration of No. 4, and FIG. 4 is a schematic circuit diagram thereof. A power source 16 is connected to the linear electrode 17 embedded in the circumferential surface of the sleeve 12C, and a predetermined voltage (1) is applied from the power source 16. Further, the cylindrical electrode body 3 is made of an aluminum vibrator or the like, and a predetermined voltage 2 is applied from a power source 3b connected to the rotating shaft 3a. The toner T on the film 14 shown in FIG. 4 is transferred to the fixed sleeve 13 by the magnetic force of the magnet roll 12b as the magnet roll 12b rotates in the direction of arrow C. The film adheres to the film and is further conveyed from the fixing sleeve 13 to the upper surface of the film 14.

The film 14 is made of polyethylene terephthalate (PET) with a thickness of several μm, and control electrodes 14a and 14b are formed within the film 14. This control electrode 1
4a and 14b are formed to be inclined at a predetermined angle with respect to the arrangement direction (main scanning direction) of the shaft 3a of the cylindrical electrode body 3, as will be described later. Therefore, the gap 14' is also formed to be inclined at a predetermined distance with respect to the axis 3a of the cylindrical electrode body 3. Although the control electrodes 14a and 14b are shown filled in with black in FIG. 3, they are composed of a plurality of control electrodes in the main scanning direction. A high voltage pulse signal is supplied from the pulse signal output section 15 to each control electrode 14b. FIG. 5 particularly shows the formation of the gap 14' where the control electrodes 14a, 14b are not formed, and shows the arrangement relationship with the linear electrode 17 when the sleeve 12c is unfolded.

In addition, FIG. 1 further shows a gap 14'(14a'14
b′ 14c′, . . . ) is a diagram showing the formation state in detail. That is, the linear electrode IT (17a, 17b,
17c, . . .), the sleeve 12c rotates in the direction of arrow C, and moves upward in the drawing in this rotational direction. Further, the direction in which the sheet is moved (sub-scanning direction) is the direction of arrow a shown in the figure, and the axial direction (main-scanning direction) of the cylindrical electrode body 3 is the direction of arrow d in the figure. In addition, L shown in the same figure
SP indicates the width of the linear electrode 17 in the main scanning direction, and in the case of this embodiment, since each control electrode 14a, 14b is configured to process dot printing, sr is -DS (however, DS indicates the size of one dot)
, Also, as shown in the figure, linear electrodes 17a, 11b,
11cm-. are respectively the gap parts 14a' and 14b' 1
4c'...-, while the signal output from the control signal output section 15 crosses the corresponding control? Since the voltage is applied to the ilt pole 14b, when the printing process for one line is completed, one dot (DS) is applied to the first printing position (for example,) in the direction of arrow C.
This means that the final printing position CDI') is misaligned.

Therefore, in order to compensate for this printing position deviation in advance, in this embodiment, the control electrodes 14a, 14b (the gap 14a',
14b' and 14c') are arranged so as to be inclined at an angle θ- counterclockwise with respect to the main scanning direction, as shown in the figure.

This angle θ8 is the linear electrode 17a, 1 with respect to the main scanning direction.
If the clockwise inclination angle of 7b, 17c, . . . is θsp, the LSE shown in the figure is Lsp Dscot θ8. It is expressed as Therefore, t3. , θ8 is DS/LSI, and becomes Ds/LSP DS cotθsp.

Now, by substituting -Ds into the above equation for LSP=, we get t
, θ is (K-cotθSr) −', and this angle θ. A gap 14' is formed by tilting the gap 14'.

When printing is performed using the electrostatic recording device configured as described above, the toner T is transferred to the printing area F (the above-mentioned cylindrical electrode body 3 and the linear electrode via the gap 14') as the magnet roll 12b rotates. 17). At this time, the electric field for attracting the toner T toward the paper P is not limited to the voltage generated between the voltage (1) applied to the linear electrode 17 and the voltage (2) applied to the cylindrical electrode body 3. unable to form,
When a high voltage pulse signal output from the control voltage output section 15 is applied to the control electrodes 14a and 14b, the gap 1
4'. FIG. 6 is a diagram showing the formation state of the electric field E created at this time, and a beam-shaped electric field E is formed between the cylindrical electrode body 3 and the linear electrode 17 via the gap 14'. Further, the electric field E formed through the gap 14' at this time has a dot-shaped cross section as shown in FIG.

Then, by feeding the paper P between the cylindrical electrode body 3 and the film 14, the toner T on the film 14 moves along the electric field E and is attracted to the bottom surface of the paper P in the form of a dot, as shown in FIG. do.

Also, during this recording operation, printing is performed sequentially on the paper P by the electric field E, but the gap 14' is at an angle θ as described above.
- Since it is formed at an angle and the angle corresponds to the moving speed of the paper P, the printing position on the paper P is parallel to the main scanning direction and no printing deviation occurs.

Therefore, by sequentially performing the above printing process for each line using the electrostatic recording apparatus configured in this embodiment, printing parallel to the main scanning direction can be performed.

〔Effect of the invention〕

As described in detail above, according to the present invention, it is possible to obtain an image of extremely excellent print quality without performing slanted printing on paper as in the conventional method.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a block diagram of the main parts of an electrostatic recording device according to an embodiment, Fig. 2 is an overall block diagram of an electrostatic recording device according to an embodiment, and Fig. 3 is a diagram showing a cylindrical electrode body and A perspective view of the developing roll, Fig. 4 is a power supply connection diagram to the cylindrical electrode body, linear electrode, and control electrode, Fig. 5 is a diagram showing the distribution relationship between the gap and the linear electrode, and Fig. 6 is a diagram showing the electric field E. FIG. 7 is a diagram explaining that the electric field E is formed in a dot shape. DESCRIPTION OF SYMBOLS 1... Electrostatic recording device, 2... Developing device, 3... Cylindrical electrode body, 4... Paper feed cassette, 6... Standby roll, 7... Static elimination brush, 9... Conveyor belt, 10...Fixing roll, 12...Developing roll, 12b...Magnet roll, 2c 13 ・ 14 ・ 14' 15 ・ 17 ・・Sleeve, fixed sleeve, film, ・Gap, control voltage output Part, linear electrode. Figure 4

Claims (1)

[Scope of Claims] A toner conveying body that carries toner on its surface, and a helical electrode body that is rotatably disposed on the opposite side to the toner conveying surface of the toner conveying body and has a helical electrode on its peripheral surface. a control electrode disposed between the toner conveying surface of the toner conveying body and the spiral electrode body; and a cylindrical electrode disposed opposite to the toner conveying surface side of the toner conveying body; In an electrostatic recording device that transfers toner on the toner conveying body to a sheet of paper conveyed between the cylindrical electrode and the toner conveying body by applying a signal voltage according to print information to the control electrode, the control electrode is the angle θ_ with respect to the axial direction of the cylindrical electrode
w Consists of a plurality of tilted divided electrodes, and the θ_w is the angle between the helical electrode and the axial direction of the cylindrical electrode. θ_s_p
When t_a_nθ_w=(K-cotθ_s_p)
An electrostatic recording device characterized in that ^-^1 (where K is any integer).