JPH0511622A - Rotary type liquid developing device - Google Patents

Abstract

PURPOSE:To reduce the number of parts and to attain reduction in cost by simplifying the structure of a rotary type liquid developing device. CONSTITUTION:Plural developing areas 27a-27d provided with plural liquid grooves 28 and a squeezing groove 30, etc., respectively, are formed in a circumferential direction at an interval, on the cylindrical face of a cylindrical developing unit main body 26, the developing liquids of each color are circulated in the liquid grooves 28 of each developing area, and the developing unit main body 26 is arranged so that an electrostatic recording form 1 arcuately comes into contact with the cylindrical face of the main body 26. Moreover, a driving device rotating/driving the developing unit main body 26 is provided, and a constitution that a prescribed developing area is moved to a developing position, is adopted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid developing device for visualizing an electrostatic latent image formed on a recording medium with a developing solution, and more particularly to a rotary liquid developing device for developing a color image.

[0002]

2. Description of the Related Art Generally, in order to record a color image, images of respective colors of black, cyan, magenta and yellow are superposed, and therefore, development of respective colors of black, cyan, magenta and yellow is required.

Conventionally, for such multi-color development, a plurality of independent developing devices arranged in series along a conveyance path of a recording medium (electrostatic recording paper) have been used, or a rotating body has been used. A so-called rotary developing device is used in which a plurality of developing devices provided are selectively moved to a developing position by rotation of a rotating body. Examples of such a rotary developing device are, for example, JP-A-62-294269, JP-A-63-41871, JP-A-63-149664, JP-A-63-191169 and JP-A-63-191169. It is disclosed in each publication of 64-62672.

In general, a structure using a rotary developing device requires a smaller space for arrangement as compared with a structure using a plurality of developing devices arranged in series, which is advantageous for downsizing of the device. The control of the position and the like becomes easy. This rotary developing device is also used for liquid development.
FIG. 9 shows an example of an electrostatic recording device using a conventional rotary type liquid developing device. Reference numeral 1 is electrostatic recording paper as a recording medium, 2 is a roll for feeding the electrostatic recording paper 1, and 3 is A guide roller 4, a recording head for forming an electrostatic latent image on the electrostatic recording sheet 1, a platen roller 5 for pressing the electrostatic recording sheet 1 against the recording head 4, and a rotation 6 for developing the electrostatic latent image. Liquid developing device, 7 is an optical system unit that detects the registration mark recorded on the electrostatic recording paper 1, 8 is a sensor back roller, 9 is a drive roller that conveys the electrostatic recording paper 1,
10 and 11 are pinch rollers and 12 is a take-up roller.

The rotary liquid developing device 6 includes four developing devices 1.
4, that is, the developing device 14a for black, the developing device 14b for cyan, the developing device 14c for magenta, and the developing device 1 for yellow.
4d is arranged on the rotating body 15 at equal intervals in the circumferential direction. Each of these developing devices 14 has the same structure,
As shown in FIGS. 10, 11, and 12, the upper surface (developing surface) that contacts the electrostatic recording paper is a flat surface, and a plurality of liquids in which the developing solution is circulated are flat surfaces. Groove 16
An air groove 17 and a squeeze groove 18 which is adapted to be vacuum-sucked. Further, as shown in FIG. 12, a developer supply pipe 19 connected to a developer tank (not shown) is connected to one end so that the developer can be supplied to the liquid groove 16 through the through hole 20. As shown in FIG. 11, a suction pipe 21 connected to a vacuum pump (not shown) is connected to the opposite end, and a through hole 22 communicating with the liquid groove 16 and a through hole communicating with the squeeze groove 18 are formed. The developer in the liquid groove 16 and the squeeze groove 18 is sucked via 23. Therefore, by the action of the vacuum pump,
The developer in the developer tank is made to flow into the liquid groove 16 and electrostatic recording paper 1
It is possible to circulate the developing solution by carrying out the development, and returning the excessive developing solution in the solution groove 16 and the developing solution removed from the electrostatic recording paper in the squeeze groove 18 to the developing solution tank again. Further, in FIG. 9, a drive device (not shown) is provided for the rotating body 15 so as to rotate the rotating body 15 and stop the rotating body 15 at a predetermined position so that a desired developing device or an intermediate position between the developing devices is a developing position. Has been contacted.

In the electrostatic recording apparatus having the above structure, first, as shown in FIG.
In the state where the black developing device 14a is at the developing position, the electrostatic recording paper 1 runs in the direction of arrow A, and the recording head 4 forms an electrostatic latent image of a black image. 14a develops. The electrostatic recording paper 1 on which the black image is recorded is once wound up by the winding roller 12, and when a predetermined image is recorded, it is rewound onto the original roll 2 and then the cyan developing device 14b is moved to the developing position. , The electrostatic recording paper is fed again in the direction of arrow A, and a cyan image is formed. The same operation is repeated thereafter to form a color image.

In the above operation, when the developing device 14 develops, as shown in FIG.
4 is in contact with the flat surface of the upper surface of 4, ie, the developing surface, and the electrostatic recording paper 1 is attracted to the developing surface of the developing device 14 by operating the vacuum pump connected to the suction tube 21. The developing solution is caused to flow into the liquid groove 16 by vacuum suction, and thereby the development is performed. Further, excess developer is sucked and removed from the squeeze groove 18.

[0008]

However, in such a structure, the developing surface of the developing device must be brought into close contact with the electrostatic recording paper, and therefore the positional accuracy of the developing surface of the developing device becomes important.
The accuracy of the individual parts that make up the developing device and the positional accuracy with respect to the electrostatic recording paper in the assembled state are required, and further, the repeated accuracy of rotating and positioning is also required, which raises the problem of high manufacturing cost. there were.

Further, four high-precision developing devices are required, and moreover, they must be accurately attached to the rotating body, which is also expensive in this respect. Further, when the number of liquid grooves through which the developing solution flows is increased in order to improve the developing efficiency, the width of the developing surface becomes wider, and the turning diameter [see D _{2 in} FIG. 8 (b)] becomes larger. There was also a problem that a large amount of private space was needed inside.

The present invention has been made in view of the above-mentioned problems, and has a relatively simple structure, does not require much increase in positional accuracy, and is capable of reducing manufacturing cost, and is a rotary liquid developing apparatus. The purpose is to provide.

[0011]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention uses a single cylindrical developing device main body instead of using developing devices as separate parts corresponding to each color as in the prior art. To form a plurality of developing areas by forming a plurality of grooves in a plurality of areas spaced apart from each other in the circumferential direction of the cylindrical surface of the developing device main body, and circulating a developing solution in the grooves of each developing area. In addition to the above, there is provided a drive device for rotating the developing device main body so that each developing area on the cylindrical surface moves to and stops at the developing position where it contacts the recording medium.

[0012]

As described above, according to the present invention, since a plurality of developing areas are formed by forming the grooves through which the developing solution flows on the cylindrical surface of the cylindrical developing device main body, one developing area is positioned at the developing position. , One color can be developed by bringing the recording medium into contact with the developing area and running, and by rotating the developing device main body to another developing area at the developing position, another color can be developed. Development can be performed. At this time, since the recording medium contacts the cylindrical surface of the developing device main body in an arc shape over a certain range, even if the positional accuracy of the developing device main body is somewhat inferior, the recording medium surely adheres to the cylindrical surface. Good development can be performed. Also, since the groove is directly formed on the cylindrical surface of the single developing device main body to form the developing area, the structure is simple compared to the conventional case where a plurality of developing devices are attached to the rotating body, and the number of parts is reduced. Can be reduced.

[0013]

2 is a schematic side view showing an electrostatic recording apparatus equipped with a rotary type liquid developing device 25 according to an embodiment of the present invention. The same parts as those of the conventional example shown in FIG. Shows. That is, 1 is electrostatic recording paper as a recording medium, 2
Is a roll for feeding out the electrostatic recording paper 1, 3 is a guide roller, 4 is a recording head for forming an electrostatic latent image on the electrostatic recording paper 1, and 5 is for pressing the electrostatic recording paper 1 against the recording head 4. A platen roller, 7 is an optical system unit that detects a registration mark recorded on the electrostatic recording paper 1, 8 is a sensor back roller, 9 is a drive roller that conveys the electrostatic recording paper 1, and 10 and 11 are pinch rollers. , 12 are take-up rollers.

The rotary liquid developing device 25 provided for visualizing the electrostatic latent image formed on the electrostatic recording paper 1 is
The electrostatic recording paper 1 is provided with a cylindrical developing device main body 26 arranged so as to contact a part of the cylindrical surface in an arc shape. As shown in FIGS. 1 and 3 to 5, the developing device main body 26 has a hollow cylindrical shape, and a plurality of grooves are formed in four regions spaced apart from each other in the circumferential direction of the cylindrical surface. Thus, four developing areas 27a, 27b, 27c and 27d are formed. These developing areas 27a to 27d correspond to black, cyan, magenta, and yellow, and each has a liquid groove 28 in which a plurality of developing solutions flow and an air groove 2.
9, a squeeze groove 30, and a cut groove 31, and a grooveless surface 32 is formed between each developing area.

A pipe adapter 35 having a gear 34 is attached to one end of the developing device main body 24, and a pipe adapter 36 having no gear is attached to the opposite end. As shown in FIG. 6, the pipe adapter 35 has a connecting portion 37 that is inserted into the developing device main body 26.
Vertical holes 38a to 38d (see FIG. 4) are formed in the connecting portion 37 at positions corresponding to the developing areas 27a to 27d, and horizontal holes 39a to 39d extending to the outer end surface of the pipe adapter 35 are formed in the vertical holes. ing. A vip 40 for supplying a developing solution is connected to each of these lateral holes, and is connected to a developing solution tank (not shown) of a corresponding color. As can be seen from FIG. 4, the developing device main body 26
The liquid grooves 28 in the vertical holes 38a of the pipe adapter 35.
A through hole 41 that communicates with 38d is formed. The pipe adapter 36 on the opposite side has a similar structure. As shown in FIG. 5, the vertical holes 43a to 43d and the horizontal holes 44a to 4d are formed.
4d is formed, and a pipe 45 for vacuum suction (see FIG. 3) is connected to each of the lateral holes 44a to 44d,
Each is connected to the corresponding vacuum pump. Also,
As shown in FIG. 5, in the developing device main body 26, the liquid grooves 28 and the squeeze grooves 30 are formed in the vertical holes 43 a of the pipe adapter 36.
Through holes 46 and 47 are formed so as to communicate with the through holes 43 to 43d. Thus, as shown in FIG. 1, one development area,
For example, the electrostatic recording paper 1 is brought into contact with 27a, and the corresponding vacuum pump is operated in a state in which the liquid groove 28, the squeeze groove 30 and the like are sealed, so that the developer in the developer tank is transferred to the pipe 40 and the pipe adapter 35. The developer can be circulated through the liquid groove 28 via the pipe adapter 36 and the pipe 45 and returned to the original developer tank by the vacuum pump. At the same time, the developer adhered to the electrostatic recording paper can be removed by the squeeze groove 30.

In FIG. 3, a cylindrical developing device main body 26 is provided.
Is the pipe adapters 35 and 3 attached to both ends thereof.
It is rotatably held on the side plate 50 by 6 and is rotationally driven by the drive motor 51. The drive motor 51 constitutes a drive device that rotates and stops the developing device main body 26 so that a desired developing area of the developing device main body 26 or an intermediate position thereof is a developing position where the electrostatic recording paper 1 is brought into contact with the developing position. ..

The operation of the rotary type liquid developing device constructed as described above will be described below.

When recording is performed on the electrostatic recording paper 1, as shown in FIG. 7A, one developing area 27a of the developing device main body 26 is set at the developing position where the electrostatic recording paper 1 is brought into contact with the developing position. It is positioned. In this state, the electrostatic recording paper 1 runs in the direction of arrow A, comes into close contact with the developing area 27a of the developing device main body 26, and is developed by the developing solution flowing in the liquid groove 28. At this time, the developing device main body 26 is such that the electrostatic recording paper 1 is the developing device main body 26.
Since it is arranged so as to make an arcuate contact with the developing area 27a, even if the height of the developing device main body 26 or the stop position in the rotation direction is a little misaligned, the electrostatic recording paper 1 comes into close contact with the developing area 27a. And good development is performed.
In other words, the developing device main body 26 is not required to have high precision in processing precision, mounting position precision, rotation stop position precision, and the like, and thus is made with relatively rough precision.

When the image formation of one color is completed, FIG.
As shown in (b), the developing device main body 26 is rotated,
The grooveless surface 32 between the development areas is the development position. In this state, the electrostatic recording paper 1 is rewound in the direction of arrow B.

Thereafter, by repeating the same operation,
Images of a plurality of colors are superimposed on the electrostatic recording paper 1, and color image recording is performed.

FIG. 8 shows the space occupied by the cylindrical developing device main body 26 according to the above embodiment and the conventional developing device 6 in comparison. An orbiting diameter D ₁ of the case where the developing width required development secured to the cylindrical surface of the cylindrical developing body 26 shown in FIG. 8 (a), with a flat surface showing the same development width in FIG. 8 (b) As can be seen from the figure, when compared with the turning diameter D ₂ when it is secured in the developing device 14, it is naturally smaller when the cylindrical surface is used. Therefore, according to the present invention, there is an advantage that the occupied space can be reduced.

In the above embodiment, four developing areas 27a to 27d are formed on the main body of the developing device to develop four colors of black, cyan, magenta and yellow. However, the present invention is not limited to four colors. It is not limited and may be applied to other plural colors.

[0023]

As is apparent from the above description, according to the present invention, a plurality of developing areas, each of which is formed by forming a groove in which a developing solution flows on the cylindrical surface of a single cylindrical developing device main body, is provided. And the developing solution is circulated in the grooves of the respective developing areas, and the cylindrical developing device main body is arranged such that the developing areas of the cylindrical surface contact the recording medium. Since the structure is such that a drive device for moving to and stopping the rotation is provided, the structure is simple as compared with the conventional case where a plurality of developing devices having a flat developing surface are attached to the rotating body. The number of parts can be reduced by using this method, and good development is possible even if the processing accuracy of the parts, the mounting accuracy, the positioning accuracy of the rotation stop position, etc. are reduced, and the manufacturing cost of the device can be reduced. Using Space occupied is reduced in a more turning diameter in the electrostatic recording apparatus is reduced, also Hakare the weight of the developing unit main body, can be made compact in the driving device for rotating the rotation load is reduced along with it or the like,
It has various effects.

[Brief description of drawings]

1 is a schematic cross-sectional view of a rotary liquid developing device according to an embodiment of the present invention, which is a cross-sectional view taken along the line C-C of FIG.

FIG. 2 is a schematic side view showing an electrostatic recording device including a rotary liquid developing device according to an embodiment of the present invention.

FIG. 3 is a schematic plan view of the rotary liquid developing device.

FIG. 4 is a sectional view taken along the line DD of FIG.

5 is a sectional view taken along the line EE of FIG.

FIG. 6 is a schematic perspective view of a pipe adapter 35 used in the rotary liquid developing apparatus.

FIG. 7 is a view for explaining the operation of the rotary liquid developing apparatus, wherein (a) is a schematic cross-sectional view of the developing device main body showing a state during development, and (b) is a developing device main body showing a state during rewinding. Schematic cross section

FIG. 8 shows a comparison of the exclusive space between the rotary liquid developing apparatus and the conventional rotary liquid developing apparatus. FIG. 8A is a schematic side view of the developing device main body according to the above embodiment, and FIG. Schematic side view of the developing device

FIG. 9 is a schematic side view showing an electrostatic recording device including a conventional rotary liquid developing device.

FIG. 10 is a schematic plan view of a developing device used in a conventional rotary type liquid developing device.

11 is a cross-sectional view taken along the line FF of FIG.

12 is a sectional view taken along the line GG in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrostatic recording paper 4 Recording head 6 Rotary liquid developing device 25 Rotary liquid developing device 26 Developing device main body 27a, 27b, 27c, 27d Development area 28 Liquid groove 29 Air groove 30 Squeeze groove 31 Slit groove 32 Non-groove surface 35 , 36 pipe adapter

Claims (1)

Claim: What is claimed is: 1. A plurality of grooves, each of which has a cylindrical surface with which a recording medium to be developed comes into contact, and a plurality of grooves are formed in a plurality of regions spaced apart from each other in the circumferential direction of the cylindrical surface. A cylindrical developing device main body having a developing area, means for circulating a developing solution in the groove of each developing area, and moving and stopping each developing area of the developing device main body to a developing position in contact with a recording medium. A rotary type liquid developing device having a driving device for driving.