KR100316651B1 - Optical scanning unit for printing equipment - Google Patents

Abstract

The present invention relates to an optical scanning unit for a printing machine which scans light into the photosensitive medium to form an electrostatic latent image on the photosensitive medium of the printing machine. The optical scanning unit of the present invention includes a transparent window for closing an opening of a casing, a cleaning member movably installed in contact with the window, and means for moving the cleaning member so that foreign matters attached to the window can be removed. Since the foreign matter is prevented from penetrating into the casing through the opening to contaminate the light source or the lens, the foreign matter on the window can be removed by the cleaning member moved in contact with the window.

Description

Optical Scanning Unit for Printing Machine

The present invention relates to an optical scanning unit for a printing machine which scans light into the photosensitive medium to form an electrostatic latent image on the photosensitive medium of the printing machine.

A principal portion of an example of a printing apparatus for printing an image on printing paper such as a copying machine or a printer is shown structurally in FIG. The printing apparatus scans light through a laser scanning unit 30 on a belt-shaped photosensitive medium 10 which is supported by a plurality of rollers 11 and runs to form an electrostatic latent image. And developing the electrostatic latent image as a toner image by supplying a developing solution to the developing device 12, and then transferring the toner image onto printing paper P passing between the transfer roller 14 and the fixing roller 15 to produce a desired image. It can be printed.

The optical scanning unit 30 generally includes a casing 31 having an opening 311 and a light source 32 such as a laser diode provided in the casing 31, as shown in FIG. 2. . The light emitted from the light source 32 is redirected along the width direction W of the photosensitive belt 10 by light direction converting means such as a rotary face mirror 33 and the opening of the lens 34 and the casing 31. Scanned to the photosensitive medium 10 through 311. As described above, the electrostatic latent image is formed on the photosensitive medium 10 by the light scanned by the photosensitive medium 10.

In the optical scanning unit, however, the opening 311 is formed in the casing 31 so that the light emitted from the light source 32 can be scanned into the photosensitive belt 10 as described above. When foreign matter such as dust or the like penetrates into the casing 31 through the opening 311 or replaces parts such as the developer 12, ink is separated from the developer 12 so that the casing 31 through the opening 311. ) Will penetrate into). In this case, a foreign material such as ink is attached to the lens 34, the rotating mirror 33 or the light source 32, etc., and a portion of the electrostatic latent image is missing due to the foreign matter such as ink attached to the printing quality. There is a problem of deterioration.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and provides an optical scanning unit for a printing apparatus having an improved structure around an opening of a casing so as to prevent external foreign substances such as ink or dust from penetrating into the casing through the opening. There is a purpose.

1 is a schematic structural diagram of a main part of an example of a printing machine;

2 is a schematic perspective view of a conventional optical scanning unit applied to the printing apparatus shown in FIG.

3 is a schematic perspective view of an optical scanning unit according to an embodiment of the present invention;

4 is a schematic cross-sectional view taken along line IV-IV shown in FIG. 3;

5 is a schematic cross-sectional view of an optical scanning unit according to another embodiment of the present invention.

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

10 ... Photosensitive media 31 ... Casing

311 ... opening 32 ... light source

41 Window 42 Cleaning member

44, 54 Motor 45 Drive pulley

46 ... Full pulley 47 ... Belt

55 Feed screw 57 Nut member

In order to achieve the above object, an optical scanning unit for a printing apparatus according to the present invention is to scan light into the photosensitive medium in order to form an electrostatic latent image on the photosensitive medium of the printing machine. And a casing having an opening formed therein so that light emitted from the film can be scanned into the photosensitive medium, wherein the casing is provided in the opening of the casing to close the opening, and is movable in contact with the window. And a cleaning member moving means for moving the cleaning member so that the foreign matter attached to the window can be removed.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. 3 is a schematic perspective view of an optical scanning unit according to an exemplary embodiment of the present invention, and FIG. 4 is a schematic cross-sectional view taken along the line IV-IV shown in FIG. 3.

3 and 4, the optical scanning unit 40 of this embodiment is similar to the conventional optical scanning unit 30 described with reference to FIG. 2, and has a casing 31 having an opening 311 and the casing ( 31, a light source 32 incorporated therein, a rotating polygon mirror 33 as a light direction converting means, and a lens 34 are provided. Since the structure and function of each of these members are the same as the structure and function of each of the members of the same name provided in the conventional optical scanning unit, a detailed description thereof will be omitted.

On the other hand, the optical scanning unit 40 of the present embodiment comprises the window 41, the cleaning member 42, and the cleaning member moving means to form a feature of the present invention.

The window 41 is made of glass of transparent material or transparent high-strength plastic material to allow light from the light source 32 to pass therethrough, and is fixed to the opening 311 of the casing 31 by bonding or ultrasonic welding. The opening 311 is closed.

The cleaning member 42 may be moved by the cleaning member moving means while being in close contact with the window 41, and at the time of movement, the cleaning member 42 may have a low sponge or low density to prevent scratches on the surface of the window 41. It is preferable to be formed of soft rubber or the like.

Various configurations may be employed as the cleaning member moving means. In this embodiment, a motor 44 capable of bidirectional rotation, a driving pulley 45, a driven pulley 46, and a belt 47 are provided. It is. The motor 44 is provided in the frame 1 for supporting the casing 31 and the like in the printing apparatus, and the drive pulley 45 is coupled to the rotation shaft of the motor 44. The driven pulley 46 is rotatably installed in the frame 1 and is spaced apart from the driving pulley 45 by an appropriate interval in the moving directions S1 and S2 of the cleaning member 42. The belt 47 is wound around the driving pulley 45 and the driven pulley 46 to travel when the driving pulley 45 is rotated by the motor 44. The fixing member 48 is fixed to one side of the belt 47, and the cleaning member 42 is coupled to the fixing member 48. The motor 44, the driving pulley 45, the driven pulley 46, the belt 47, and the like are installed so as to deviate from the emission path of the light emitted through the window 41.

In the optical scanning unit 40 having such a configuration, the opening of the lens 34 and the casing 31 while the light emitted from the light source 32 is redirected by light direction converting means such as a rotating polygon mirror 33 or the like. The basic function of scanning the photosensitive medium 10 through the window 41 of 311 and forming an electrostatic latent image on the photosensitive medium 10 by the scanned light is conventional in the optical scanning unit 30. Is the same as

However, in the optical scanning unit of this embodiment, since the opening 311 of the casing 31 is closed by the window 41, external foreign substances such as ink or dust falling from the developer 12 (see FIG. 1) are opened. Penetration into the casing 31 through 311 can be prevented. Therefore, since the lens 34, the rotating polygon mirror 33, the light source 32, or the like can always be kept in a clean state, it is effectively suppressed that the print quality is lowered.

On the other hand, even if foreign matter such as ink or dust adheres to the window 41, the window 41 can be kept clean by the cleaning member 42 and the cleaning member moving means. That is, for example, when the cleaning member 42 is located at a position (hereinafter referred to as "first position") as shown by the solid line in FIG. 4, when the motor 44 rotates in one direction by a predetermined rotational speed. The belt 47 wound around the driving pulley 45 and the driven pulley 46 is driven, and the cleaning member 42 coupled to the belt 47 is in contact with the window 41 in the direction of arrow S1. Will be moved to. As such, when the cleaning member 42 is moved to the position (hereinafter referred to as “second position”) as shown by the virtual line in FIG. 4 in contact with the window 41, the ink deposited on the window 41 Foreign matter such as dust is wiped off by the cleaning member 42.

As described above, after the cleaning member 42 is moved to the second position by wiping the window 41, when the motor 44 is rotated in the reverse direction, the cleaning member 42 again moves along the direction of the arrow S2 to the first position. The window 41 is wiped again while being moved to the position. As described above, the cleaning member 42 moved to the second position is kept at the second position or is moved back to the first position. It is up to the designer to decide which can be preset by the control programming that controls the rotation of the motor.

On the other hand, the motor 44 is rotated by a predetermined number of revolutions and accordingly described as being stopped after moving the cleaning member 42 to the second position, for example, by installing a switch 49 in the frame (1) In addition, while the cleaning member 42 is moved by the rotation of the motor 44, the switch 49 is pressed by the fixing member 48, and when the switch 49 is pressed, the motor 44 stops. Or rotate in the reverse direction.

The operation timing of the cleaning member 42, that is, the operation timing of the motor 44, may also be appropriately set by the designer. For example, a cleaning member 42 is installed by installing a sensor (not shown) for detecting whether a foreign material is attached to the window 41 and allowing the motor 44 to operate based on the foreign material detection signal from the sensor. It is possible to reciprocate by the number of times, and instead of installing the sensor, it is also possible to cause the motor 44 to be operated for an appropriate time at an appropriate timing, such as when the printer is powered on by programming.

FIG. 5 is a schematic cross-sectional view of an essential part of an optical scanning unit of another embodiment according to the present invention, and corresponds to FIG. 4.

In the optical scanning unit of the present embodiment, members having the same reference numerals as those of the members of the optical scanning unit 40 described with reference to FIGS. 3 and 4 have the same configuration and function as each other and will not be described in detail. do.

The optical scanning unit 50 of this embodiment includes a motor 54, a transfer screw 55, and a nut member 57 as a cleaning member moving means.

The motor 54 is installed in the frame 1 as being capable of bidirectional rotation. One end of the transfer screw 55 is coupled to the rotating shaft of the motor 54 through the coupler 56 and the other end is rotatably supported by the frame 1. The nut member 57 is only installed in the frame 1 to prevent the rotation of the feed screw 55 in the longitudinal direction (S1, S2) and rotation of the feed screw 55 as the central axis of rotation. It is screwed to the feed screw 55. The cleaning member 42 is coupled to the nut member 57 and in contact with the window 41.

In the optical scanning unit 50 having such a configuration, when the motor 54 rotates forward and backward, the feed screw 55 rotates forward and backward together, and the nut member 57 screwed to the feed screw 55 transfers the feed screw. It is reciprocated along the longitudinal directions S1 and S2 of 55. As the nut member 57 is reciprocated as described above, the cleaning member 42 coupled to the nut member 57 is moved in contact with the window 41 to cleanly wipe the surface of the window 41.

As described above, the optical scanning unit of the present invention includes a transparent window for closing the opening of the casing, a cleaning member installed to be movable in contact with the window, and a cleaning member to remove foreign substances attached to the window. Since it has a means for moving the, foreign matter from the outside through the opening is prevented from contaminating the light source, lens, etc., the foreign matter on the window is cleaned by the cleaning member moved in contact with the window Can be removed.

Claims (3)

Scanning light into the photosensitive medium to form an electrostatic latent image on the photosensitive medium of the printing machine, a light source and a casing having an opening so that the light source is embedded and the light emitted from the light source can be scanned into the photosensitive medium. In the optical scanning unit for a printing machine provided, A transparent window provided in the opening of the casing to close the opening; A cleaning member installed to be movable in contact with the window; And a cleaning member moving means for moving the cleaning member so that the foreign matter attached to the window can be removed. According to claim 1, The cleaning member moving means, A motor capable of bidirectional rotation, A drive pulley rotated by the motor, A driven pulley installed to be spaced apart from the driving pulley in the moving direction of the cleaning member; And a belt wound around the driving pulley and the driven pulley and circulating in the rotation of the driving pulley, wherein the cleaning member is coupled to one side thereof. According to claim 1, The cleaning member moving means, A motor capable of bidirectional rotation, A feed screw disposed to extend along the moving direction of the cleaning member and rotated by the motor; And a nut member screwed to the transfer screw and reciprocally movable in the longitudinal direction of the feed screw when the feed screw is rotated, wherein the nut is coupled to the cleaning member.