KR100319848B1 - Developing solution concentration measuring device of wet printing machine - Google Patents

Abstract

First and second wall members spaced apart from each other so as to pass through the developer including the toner and the liquid carrier therebetween, and provided to transmit incident light therebetween; A light source for irradiating light to the developer between the members, a photodetector provided opposite to the light source on the outside of the second wall member, and a circuit unit for detecting the concentration of the developer from the detected light amount of the photodetector And vibrating means installed on the first and second wall members to vibrate the first and second wall members, thereby preventing a decrease in the light transmittance caused by the toner attached to the first and second wall members. Disclosed is a developer concentration measurement apparatus for a wet printer.

The developing solution concentration measuring apparatus of the wet printing machine includes vibrating means for vibrating the first and second wall members, thereby preventing a decrease in the light transmittance caused by the toner adhered on the optical path between the light source and the photodetector. The concentration can be measured accurately.

Description

Developer concentration measurement device of wet press

The present invention relates to a developing solution concentration measuring apparatus of a wet printing machine, and more particularly, to a developing solution concentration measuring apparatus of a wet printing machine capable of determining the concentration of the developing solution by measuring the light transmittance of the developing solution so as to realize an optimal printing state. .

Generally, in a wet printer, an image recording surface of a photosensitive medium such as a photosensitive belt or photosensitive drum is charged, and the potential level is changed by light selectively scanned on the image recording surface to form an electrostatic latent image. Then, the developer which is charged at the latent electrostatic image position is attached to form an image.

1 is a view schematically showing a general wet printing machine.

Referring to the drawings, the photosensitive belt 1 rotates the endless track in a state supported by the guide roller (3). The electrostatic latent image remaining on the video recording surface of this photosensitive belt 1 is removed from the erasing machine 11. The video recording surface is then charged uniformly to a predetermined potential while passing through the corona charging device 13.

The image recording surface of the photosensitive belt 1 charged to the predetermined potential in this manner is selectively photosensitive by the light scanned from the laser scanning unit 15, and the potential level of this photosensitive position is changed to form an electrostatic latent image. And the latent electrostatic image position passes through the developing unit 16, and the developer was attached. The developing unit 16 may develop yellow, magenta, cyan and black images, for example. The laser scanning unit 15 is provided at the front end of each of the developing units 16 to form an electrostatic latent image for each color.

At this time, the developing unit 16 is filled with a developing solution in which a color toner charged at a predetermined potential and a liquid carrier are mixed.

Here, the developer is mixed with the toner and the liquid carrier at an appropriate concentration as follows. Each color ink container 20 accommodates a developer of a dense concentration in which a liquid carrier and a color toner are mixed in a dense concentration. The carrier supply cylinder 27 houses a liquid carrier. Therefore, the dense color developer supplied from the ink container 20 is mixed with the liquid carrier supplied from the carrier supply container 27 in the working solution 25 at an appropriate concentration.

The developing solution mixed at an appropriate concentration in the working solution 25 is pumped toward the developing roller 17 by the pump 26, and is rotated by the developing roller 17 installed close to the image recording surface of the photosensitive belt 1. Thus, the photosensitive belt 1 is attached to the latent electrostatic image position to form a color image.

Thus, the photosensitive belt 1 in which the image of the color is formed on the image recording surface is dried while passing through the heating roller 28, and the liquid carrier in the developer is removed from the image recording surface of the photosensitive belt 1 so that only toner particles remain. do.

An image made of the toner attached to the photosensitive belt 1 is transferred to the transfer roller 29 and printed on the paper 30 passed between the transfer roller 29 and the fixing roller 31.

In order to maintain the image quality in the conventional wet press as described above, the concentration of the developer, that is, the mixing ratio of the toner and the liquid carrier should be appropriate.

In order to measure the concentration, a light transmitting concentration measurement device (not shown) is generally installed on the path of the developer. The concentration of the developer can be measured by irradiating light to the developer from a light source (not shown), receiving light transmitted through the developer with a photodetector (not shown), and detecting the change in the amount of transmitted light. At this time, the light source and the photodetector are spatially separated from the developer by the transparent member (not shown) through which light passes.

However, the developer concentration measuring apparatus as described above may be contaminated as the toner particles are attached to the optical path between the light source and the photodetector, that is, the transparent member, and thus the light transmittance may be lowered. May occur.

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and an object thereof is to provide a developer concentration measurement apparatus of a wet printing machine that is capable of accurately measuring the concentration of the developer with a pollution prevention means.

1 is a schematic view showing a typical wet printing machine,

2 is a perspective view schematically showing a developer concentration measuring apparatus of a wet printing machine according to an embodiment of the present invention;

3 is a cross-sectional view taken along line III-III of FIG. 2;

Figure 4 is a schematic cross-sectional view showing a developer concentration measurement apparatus of a wet printing machine according to another embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

51, 53 first and second wall members 60

65 photodetector 70 circuit part

80 ... vibration means 81 ... conductive adhesive

83 Piezoelectric element 85 Drive part

90 ... damper member

The developer concentration measurement apparatus of the wet printing machine according to the present invention for achieving the above object is provided with a spaced apart from each other so as to pass through the developer including a toner and a liquid carrier therebetween, the first and first Two wall members; A light source disposed outside the first wall member to irradiate light to a developer between the first and second wall members; A photodetector installed outside the second wall member so as to face the light source and receiving the light passing through the developer; A circuit section for detecting the concentration of the developer from the detected light amount of the photodetector; Vibrating means installed on the first and second wall members to vibrate the first and second wall members, so as to prevent a decrease in light transmittance caused by toner attached to the first and second wall members. It is characterized by.

Here, the vibration means, the piezoelectric element bonded to the outer wall of the first and second wall members with a conductive adhesive; It includes; the driving unit for applying an AC voltage to the piezoelectric sensor.

On the other hand, it is preferable to further include a damper member for absorbing vibration between the first and second wall members or between the first wall member and the light source and between the second wall member and the photodetector.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a perspective view schematically showing a developer concentration measurement apparatus of a wet printing machine according to an embodiment of the present invention, and FIG. 3 is a cross-sectional view taken along line III-III of FIG. Here, the same reference numerals as in FIG. 1 denote the same members.

Referring to the drawings, the developer concentration measuring apparatus according to the present invention is installed spaced apart from each other at a predetermined interval and the first and second wall members 51 and 53 provided to transmit incident light, and the first and second wall members ( The light source 60 and the photodetector 65, the circuit unit 70, and the first and second wall members 51 and 53 provided on the outer side of each of the first and second wall members 51 and 53, respectively, are provided on the first side. And vibrating means 80 for vibrating the second wall members 51 and 53.

The first and second wall members 51 and 53 are spaced apart by a predetermined interval therebetween so that the developer including the toner and the liquid carrier passes therethrough. The first and second wall members 51 and 53 may be provided as transparent members such as glass to transmit incident light. In addition, it is also possible to provide a window (not shown), which is provided with an opaque member and faces the light source 60 and the photodetector 65.

The first and second wall members 51 and 53 are preferably joined by the connecting member 57 so that the gap therebetween is kept constant. In the case where the developer concentration measuring device according to the present invention is installed on a supply path of a developer mixed at an appropriate concentration, that is, a path of the developer supplied from the working solution 25 toward the developing roller 17, the first and second walls As shown in FIG. 2, the members 51 and 53 and the connecting member 57 form a container 50 capable of entering and leaving the developer. On the other hand, when the developer concentration measuring apparatus according to the present invention is installed in the working solution 25 or the developing unit 16, the outer wall and the light source 60 and the first and second wall members (51, 53) The photodetector 65 is preferably provided to be isolated from the developer.

The light source 60 is installed outside the first wall member 51 to irradiate light to the developer between the first and second wall members 51 and 53. The photodetector 65 is installed on the outer side of the second wall member 53 so as to face the light source 60 to receive the light passing through the developer. By measuring the amount of light passing through the developer as described above, the turbidity of the developer, that is, the concentration, can be measured, and the change in concentration can be known by measuring the change in the amount of light passing through. The circuit unit 70 compares the input detection signal of the photodetector 65 with data of a lookup table (not shown) to detect the concentration of the developer.

In this case, the present invention includes the vibration means 80 so that toner does not adhere to the inner walls of the first and second wall members 51 and 53. In the present embodiment, the vibration means 80 is a piezoelectric element 83 bonded to the outer wall of the first and second wall members (51, 53) with a conductive adhesive 81, and the piezoelectric element ( A driving unit 85 for applying an alternating current voltage to 83; Both ends of the driving unit 85 are connected to the adhesive surface and the surface of the piezoelectric element 83. When an AC voltage is applied to the piezoelectric element 83 by the driving unit 85, the first and second wall members 51 and 53 vibrate, thereby causing toner to form on the inner walls of the wall members 51 and 53. It is not attached. Therefore, by attaching toner to the inner walls of the first and second wall members 51 and 53, it is possible to prevent an error in density measurement that may occur due to a decrease in light transmittance.

Meanwhile, according to the present invention, as shown in FIG. 4, between the first and second wall members 51 and 53, that is, between the first and second wall members 51 and 53 and the connection member 57. It is preferable to further include a damper member 90 for absorbing vibrations. The damper member 90 prevents the vibrations of the first and second wall members 51, 53 by the vibration means 80 from being transmitted to other members. Here, it is preferable that a damper member is also provided between the light source 65 and the photodetector 65 and the first and second wall members 51 and 53.

The developing solution concentration measuring apparatus of the wet printing machine according to the present invention as described above has vibrating means for vibrating the first and second wall members, so that the light transmittance by the toner adhered on the optical path between the light source and the photodetector is determined. Since a fall is prevented, the density | concentration of a developing solution can be measured correctly.

Claims (3)

A container having first and second wall members spaced apart from each other so as to pass through a developer including a toner and a liquid carrier, and configured to transmit incident light; A light source disposed outside the first wall member to irradiate light to a developer between the first and second wall members; A photodetector installed outside the second wall member so as to face the light source and receiving the light passing through the developer; Vibrating means for vibrating the first and second wall members to prevent the toner from adhering to the first and second wall members. A developer concentration measurement apparatus for a wet printer, characterized in that to prevent a decrease in light transmittance. The method of claim 1, wherein the vibration means, Piezoelectric elements bonded to the outer walls of the first and second wall members with a conductive adhesive so as to connect one electric terminal to the adhesive surface thereof; And a driving unit for applying an AC voltage to the piezoelectric element. The developer concentration measuring apparatus of the wet printer, characterized in that the conductive adhesive is applied relatively wide. The damper member of claim 1, further comprising a damper member disposed between the first and second wall members or between the first wall member and the light source and between the second wall member and the photodetector to absorb vibration. Developer concentration measurement apparatus of a wet printing machine.