KR100287154B1 - Printer photosensitive belt steering device - Google Patents

Abstract

PURPOSE: A printer photosensitive belt steering device is provided to reduce damage of the photosensitive belt that occurs when bias of the belt is corrected without tilting or biasing the whole part of a steering roller. CONSTITUTION: A printer photosensitive belt steering device includes a frame(210), a shaft(220) rotatably set inside the frame, a guide roller(230), the first and second steering rollers(240,245), and a driver(250). The guide roller guides a photosensitive belt. The first and second steering rollers correct bias of the photosensitive belt coming into contact with the outer faces of the steering rollers. The driver is arranged between the frame and the shaft and changes a rotation angle of the shaft to control a tilt angle of the portion of the fir and second steering rollers, which comes into contact with the photosensitive belt. The center of the first steering roller is eccentric in one direction with respect to the center of the shaft, and the center of the second steering roller is eccentric in the direction opposite to the eccentric direction of the first steering roller with respect to the center of the shaft.

Description

Photosensitive belt steering for printing press

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive belt steering device capable of preventing lateral slip of a photosensitive belt employed in a printing press. In detail, the present invention relates to a photosensitive belt meandering correction without tilting the entire roller supporting the photosensitive belt. The present invention relates to a photosensitive belt steering device for a press that can reduce damage to the photosensitive belt.

In general, a printer such as a laser printer is a device for forming a latent electrostatic image by scanning a laser beam on a photosensitive medium, developing with a toner of a predetermined color using a developing unit, and then transferring it to a printing paper for printing.

Referring to FIG. 1, a general printing machine includes a photosensitive belt 10 that is wound around a driving roller 20, a transfer backup roller 30, and a steering roller 41 installed in a printer main body to rotate a predetermined track.

And around the photosensitive belt 10, an erasing lamp 60 for erasing the surface potential formed on the photosensitive belt 10, a charger 70 for charging the photosensitive belt 10 whose surface potential is reset to a predetermined electric potential, and photosensitive. A plurality of laser scanning units (LSUs) 80 for scanning a laser beam on the belt 10 to form an electrostatic latent image corresponding to each color, and a plurality of developing units for developing a portion in which an electrostatic latent image is formed ( 90) is installed.

As such, in the printer provided, the photosensitive belt 10 is wound around the rollers 20, 30, 41, and meanders in the longitudinal direction of the rollers 20, 30, 41.

Therefore, the printer includes a meander detection sensor (not shown) for detecting the meandering of the photosensitive belt 10 and a photosensitive belt steering device 40 for correcting the meandering.

1 and 2, the conventional photosensitive belt steering device 40 includes a frame 42 installed on the printing main body 1, a rotating member 46 installed on the frame 42 so as to be rotatable, and The steering roller 41 is installed on the rotating member 46 to support the photosensitive belt 10 to pivot along a predetermined track, and to prevent wrinkles of the photosensitive belt 10 passing through the steering roller 41. A pair of stabilizing rollers 43 provided on the frame 42 and an adjusting unit 50 mounted on the printing main body 1 to adjust the tilt of the steering roller 41 in the up and down directions (arrow A direction) are provided. Include.

The pivot member 46 is coupled by a coupling pin 47 to the pivot bar 44 elastically coupled to the frame 42, so that the pivot member 46 can rotate about a portion where the coupling pin 47 is coupled on the XY plane. Is installed. The rotating member 46 is a pressure applied to the contact portion between the steering roller 41 and the photosensitive belt 41 by the elastic member 45 interposed between the rotating bar 44 and the frame 42. Is rotated in a direction to compensate for the imbalance. The steering roller 41 has a rotating shaft 41a coupled to the installation groove 46a formed in the rotation member 46. The mounting groove 46a is provided with an elastic piece 48 for supporting the rotating shaft 41a of the steering roller 41 by pressing in the direction of the cam member 49.

The adjustment unit 50 has a drive motor 48 fixed to the frame, the center thereof is coupled to the rotation shaft 54 of the drive motor 48, a cam member 51 having a cam groove 52, and It is coupled to the rotation member 46 and includes a rotation guide protrusion 49 installed to fit in the cam groove (52). Therefore, the position of the cam groove 52 is changed by the rotation of the drive motor 48, the height of the rotation guide projection 49 is variable. Accordingly, the steering roller 41 is rotated in the direction of the arrow A around the pivot bar 44.

Therefore, when the meandering degree of the photosensitive belt 10 is detected by the meandering detection sensor, the steering roller 41 is tilted according to the position of the cam member 51. Accordingly, the photosensitive belt 10 is moved in one width direction to correct meandering.

Each of the pair of stable rollers 43 is installed in the frame 42 in a direction parallel to the steering roller 41, the portion of the photosensitive belt 10 toward the steering roller 41, the steering roller 41 While suppressing the folding of the photosensitive belt 10 in contact with the portion passing through), the height variation of the photosensitive belt according to the steering does not affect the laser scanning unit 80.

As described above, by correcting the meandering of the photosensitive belt 10 by the tilting of the entire conventional photosensitive belt steering device 41, the folding of the photosensitive belt 10 is likely to occur. In view of this, it is necessary to have two stabilizer rollers 43 described above, and the distance between the stabilizer roller 43 and the steering roller 41 (x in FIG. 1) is controlled by the steering roller 41. Since it must be long enough to bend, there is a limit to miniaturization of the overall size.

In addition, since the elastic member 45 interposed between the rotation bar 44 and the frame 42 exerts tension on the photosensitive belt 10, the structure of releasing and installing tension is complicated.

In view of the problems described above, the present applicant has applied Korean patent application No. 97-67747 (name of the invention: a photosensitive belt steering device for a printing press, filed December 11, 1997) without tilting and meandering of the entire steering roller. A photosensitive belt steering device for a printer that can compensate for meandering of the photosensitive belt has been proposed.

Referring to FIG. 3, the photosensitive belt steering apparatus for a printer proposed by the present applicant includes a frame 110, a shaft 120 rotatably installed on the frame 110, and a rotatable on the shaft 120. A guide roller 130 installed to guide the progress of the photosensitive belt 100, a steering roller 140 disposed around the guide roller 130 and correcting the meandering of the photosensitive belt 100, and the frame 110. ) Is installed between the shaft 120 and the driving means 150 to control the rotation angle of the shaft 120.

The steering roller 140 is installed to be inclined to the shaft 120 around the guide roller 130, the inclination direction is determined by the rotation angle of the shaft 120 to eventually contact the photosensitive belt 100 The inclination angle of the portion is adjusted to correct the meandering of the photosensitive belt 100. Here, the center of the steering roller 140 coincides with the center of the guide roller 130.

The steering roller 140 has a spacer 141 installed to be inclined at a predetermined angle with respect to the outer circumferential direction of the shaft 120, and an inclination rotatably installed on the outer circumference of the spacer 141 at the same inclination angle as the spacer 141. And a shell 144 and a bearing 143 disposed between the spacer 141 and the inclined shell 144.

The inclined shell 144 is rotatably installed on the outer circumference of the spacer 141 by the bearing 143, and is in contact with the photosensitive belt 100 to correct meandering in the longitudinal direction of the shaft 120. The inclined shell 144 has a rounded outer circumferential surface so that the contact portion with the photosensitive belt 100 is wide. That is, the height of both sides of the inclined shell 144 is the same as the height of the guide roller 130 disposed around, the height of the center portion of the inclined shell 144 is higher than the height of the guide roller 130, The contact portion of the photosensitive belt 100 with the outer circumference of the inclined shell 144 may be curved to widen the contact portion with the photosensitive belt 100.

As shown in FIG. 4, when the photosensitive belt 100 traveling in the direction of the arrow + B is meandered in the direction of the arrow -C as shown in FIG. 4, the steering roller 140 is the photosensitive belt in plan view. Place the contact portion 100 and tilted to the right. Therefore, the photosensitive belt 100 is subjected to the force in the direction of rotation of the guide roller 130 and the steering force in the direction of the arrow + C in accordance with the inclination of the steering roller 140. Accordingly, the photosensitive belt 100 is gradually moved in the direction of arrow + C while turning, thereby correcting the meandering of the photosensitive belt 100 in the direction of arrow -C. Here, a force pushing the photosensitive belt 100 acts on the steering roller 140a positioned on the left side, and a force pulling the photosensitive belt 100 acts on the steering roller 140b positioned on the right side. On the other hand, the photosensitive belt has a greater steering force applied to its edge portion than the steering force applied to its central portion based on the tension of the photosensitive belt when meandering.

Therefore, in the device configured as described above, since the edge of the steering force is easily meandered at the portion where the pulling force is applied, the occurrence of wrinkles of the photosensitive belt is hardly generated. On the other hand, in the part where the pushing force is applied, since the meandering is poor compared to the edge portion of the center portion where the steering force is applied less, the wrinkles may occur in the photosensitive belt, which may cause damage to the photosensitive belt.

The present invention has been made to improve the above-described point, a photosensitive belt steering apparatus for a printing machine having an improved structure to reduce the damage of the photosensitive belt generated during the meander correction of the photosensitive belt without tilting and meandering the entire steering roller The purpose is to provide.

1 is a schematic view showing a printing press employing a conventional photosensitive belt steering device.

Figure 2 is a schematic exploded perspective view showing a conventional photosensitive belt steering device.

Figure 3 is a cross-sectional view showing a photosensitive belt steering device for a printer proposed by the applicant.

4 is a schematic diagram illustrating the operation of FIG. 3.

Figure 5 is a cross-sectional view showing a photosensitive belt steering device for a printing press according to an embodiment of the present invention.

6 to 8 are each a schematic view for explaining the operation of the photosensitive belt steering apparatus for a printing press according to an embodiment of the present invention.

<Explanation of symbols for main parts of drawing>

100 ... Photosensitive belt 210 ... Frame 211 ... Installation groove

213 ... 1st Bearing 220 ... Shaft 230 ... Guide Roller

240 ... first steering roller 245 ... second steering roller

241,246 ... Spacer 242,247 ... Set screw

243,248 3rd bearing 244,249 Inclined shell 250 Driving means

251 ... Moving Source 252 ... 1st Gear 253 ... 2nd Gear

In order to achieve the above object, a photosensitive belt steering apparatus for a printer according to the present invention includes a frame; A shaft rotatably installed in the frame; A guide roller rotatably installed with respect to the shaft and having a portion of its outer circumference in contact with the photosensitive belt to guide the progress of the photosensitive belt; First and second steering rollers disposed spaced around the guide roller, inclined at a predetermined angle with respect to the outer circumferential direction of the shaft, and rotatably installed on the shaft to correct meandering of the photosensitive belt in contact with the outer circumference. Wow; And driving means installed between the frame and the shaft to control the inclination angle of the photosensitive belt contact portions of the first and second steering rollers by varying the rotation angle of the shaft.

The center of the first steering roller is installed eccentrically in one direction with respect to the center of the shaft, and the center of the second steering roller is eccentric in a direction opposite to the eccentric direction of the first steering roller with respect to the center of the shaft. Characterized in that installed.

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

5 is a cross-sectional view showing a photosensitive belt steering device for a printing press according to an embodiment of the present invention.

As shown, the present invention is a frame 210, a shaft 220 rotatably installed on the frame 210, rotatably installed on the shaft 220 to guide the progress of the photosensitive belt 200 The guide roller 230 and the first and second steering rollers 240 and 245 arranged to be spaced apart from each other at predetermined intervals around the guide roller 230 to correct meandering of the photosensitive belt 200, and the frame It is configured to include a drive means 250 is installed between the 210 and the shaft 220 to control the rotation angle of the shaft 220.

The frame 210 has a structure in which both ends thereof face each other at a predetermined interval so that both ends of the shaft 220 may be rotatably coupled and have an installation groove 211 for installing the shaft 220. .

A first bearing 213 for rotatably supporting the shaft 220 with respect to the frame 210 is coupled to the installation groove 211.

The shaft 220 is rotatably installed on the frame 210 by the first bearing 213, the guide roller 230 and the first and second steering roller 240 on the outer peripheral surface thereof ( 245 is rotatably installed.

The guide roller 230 has a portion of its outer circumference in contact with the photosensitive belt 200 to guide the progress of the photosensitive belt 200. The guide roller 230 is a hollow cylindrical roller which is rotatably installed on the shaft 220 by a plurality of second bearings 232 and 234. The guide roller 230 is spaced apart from the first guide roller 231 and the first guide roller 231 for supporting the image area of the photosensitive belt 200 to support both sides of the photosensitive belt 200. It may include a pair of second guide roller 233.

Each of the first and second steering rollers 240 and 245 is disposed between the first guide roller 231 and each of the pair of second guide rollers 233 to correct the meandering of the photosensitive belt 200. do.

That is, the first and second steering rollers 240 and 245 are installed to be inclined to the shaft 220 around the guide roller 230, and the inclination direction is determined by the rotation angle of the shaft 220. As a result, the inclination angle of the part in contact with the photosensitive belt 200 is adjusted to correct the meandering of the photosensitive belt 200.

Each of the first and second steering rollers 240 and 245 is the same as that of the spacers 241 and 246 that are inclined at a predetermined angle with respect to the outer circumferential direction of the shaft 220 and the spacers 241 and 246. A third bearing disposed between the inclined shells 244 and 249 rotatably installed on an outer periphery of the spacer 241 at an inclined angle, and a third bearing disposed between the spacers 241 and 246 and the inclined shells 244 and 249. 243) (248).

The spacers 241 and 246 have a hollow having a diameter corresponding to the outer diameter of the shaft 220 so as to be inclinedly coupled to the shaft 220. The hollow is formed to be inclined with respect to the outer circumference of the shaft 220 so that the entire spacers 241 and 246 are inclined when the hollow is coupled to the shaft 220. Here, the centers of the spacers 241 and 246 are eccentrically installed with respect to the center of the shaft 220.

In addition, a fastening groove is formed across the shaft 220 and the spacers 241 and 246. The spacers 241 and 246 are assembled by assembling the set screws 242 and 247 into the fastening groove. Each may be fixed to the shaft 220.

The inclined shells 244 and 249 are rotatably installed on the outer circumference of the spacers 241 and 246 by the third bearings 243 and 248. The inclined shells 244 and 249 are in contact with the photosensitive belt 200 and the shaft ( 220) Correct meandering in the longitudinal direction. The inclined shells 244 and 249 preferably have a rounded outer circumferential surface such that the contact portion with the photosensitive belt 200 is wide. That is, the height of both sides of the inclined shell 244 is the same as the height of the guide roller 230 disposed around, the height of the center portion of the inclined shell 244 is higher than the height of the guide roller 230, The contact portion of the photosensitive belt 200 with the outer circumference of the inclined shell 244 may be curved to widen the contact portion with the photosensitive belt 200.

Here, the first and second steering rollers 240 and 245 have a circular shape having a predetermined diameter with respect to their respective rotation centers (240a and 245a in FIG. 6), and the rotation centers 240a and 245a. ) Is distinguished from the steering device shown in FIG. 3 in that it is located eccentrically with respect to the center of rotation (220a in FIG. 6) of the shaft 220.

The center 240a of the first steering roller 240 is eccentrically installed in one direction with respect to the center 220a of the shaft 220, and the center 245a of the second steering roller 245 is the shaft. It is installed to be eccentrically opposite to the eccentric direction of the first steering roller 240 with respect to the center (220a) of the (220). The first and second steering rollers 240 and 245 configured as described above are in contact with the photosensitive belt 100 according to the steering direction by controlling the rotation angle of the shaft 220 by the driving means 250. You can adjust the degree of protrusion of the part.

The driving means 250 is installed between the frame 210 and the shaft 220 to adjust the inclination directions of the first and second steering rollers 240 and 245 to meander the photosensitive belt 200. The rotation angle of the shaft 220 is controlled to be corrected. To this end, the driving means 250 includes a driving source 251 for providing a rotational force, and gear members 252 and 253 for transmitting the rotational force provided from the driving source 251 to the shaft 220.

The drive source 250 is installed in the frame 210 and has a rotating shaft that is rotated. The gear member includes a first gear 252 that is rotated about the rotation axis and a second gear 253 that is rotated about the shaft 220 and engaged with the first gear 252. Here, the rotation axis of the drive source 251 without the gear members 252 and 253 may be disposed coaxially with the shaft 220 to control the rotation angle of the shaft 220.

6 to 7, the operation of the photosensitive belt steering apparatus for a printer according to an embodiment of the present invention will be described.

FIG. 6 shows the positions of the first and second steering rollers 240 and 245 when the photosensitive belt 100 is driven without any bias.

Since the actual operation is unnecessary, each of the first and second steering rollers 240 and 245 may be disposed in parallel with the traveling direction of the photosensitive belt 100 with respect to a portion in contact with the photosensitive belt 100. 100) does not flow left and right. FIG. 6 is a view of the first and second steering rollers 240 and 245 viewed from the side and inclined upward and downward.

In this case, the centers of the first and second steering rollers 240 and 245 are horizontally eccentric to the center of the shaft 220, so that the first and second steering rollers 240 and 245 are photosensitive belts. Protrudes to the same height toward the (100).

7 illustrates the positions of the first and second steering rollers 240 and 245 arranged to steer the photosensitive belt 100 in the -C direction when the photosensitive belt is driven in the + C direction.

In this case, by rotating the shaft 220 by a predetermined angle by the driving means 250, the center 240a of the first steering roller 240 is the upper portion of the center 220a of the shaft 220. The center 245a of the second steering roller 245 is positioned below the center 220a of the shaft 220. Accordingly, the long diameter outer circumference of the first steering roller 240 and the short diameter outer circumference of the second steering roller 245 are in contact with the photosensitive belt 100.

Therefore, the steering force that pulls the photosensitive belt 100 in the -C direction is large, and the steering force that is pushing is weakly acting to contact the second steering roller 245 of the photosensitive belt 100. Can prevent wrinkles.

FIG. 8 illustrates the positions of the first and second steering rollers 240 and 245 arranged to steer the photosensitive belt 100 in the + C direction when the photosensitive belt 100 is driven in the -C direction. will be.

In this case, by rotating the shaft 220 by the driving means 250, the center 240a of the first steering roller 240 is located below the shaft center 220a. The center 245a of the two steering rollers 245 is located above the shaft center 220a. Therefore, the short diameter outer circumference of the first steering roller 240 and the long diameter outer circumference of the second steering roller 245 are in contact with the photosensitive belt 100.

Therefore, the steering force that pulls the photosensitive belt 100 in the + C direction is large, and the steering force that is pushing is weakly acting to contact the first steering roller 240 of the photosensitive belt 100. Can prevent wrinkles.

As described above, the photosensitive belt steering apparatus for a printing press according to the present invention is rotatably installed on the shaft 220, and without tilting and meandering of the guide roller 230 for guiding the turning of the photosensitive belt 200. And by correcting the meandering of the photosensitive belt 200 in accordance with the rotation of the second steering roller (240, 245), it is possible to eliminate a pair of stable rollers that were used as an essential component of the prior art, the size of the entire steering device It can be miniaturized. In addition, the centers of the first and second steering rollers 240 and 245 are installed eccentrically with respect to the center of the shaft 220, thereby reducing the steering force that pushes during meandering correction of the photosensitive belt 100. Can reduce wrinkles.

Claims (3)

A frame; A shaft rotatably installed in the frame; A guide roller rotatably installed with respect to the shaft and having a portion of its outer circumference in contact with the photosensitive belt to guide the progress of the photosensitive belt; First and second steering rollers disposed spaced around the guide roller, inclined at a predetermined angle with respect to the outer circumferential direction of the shaft, and rotatably installed on the shaft to correct meandering of the photosensitive belt in contact with the outer circumference. Wow; And driving means installed between the frame and the shaft to control the inclination angle of the photosensitive belt contact portions of the first and second steering rollers by varying the rotation angle of the shaft. The center of the first steering roller is installed eccentrically in one direction with respect to the center of the shaft, and the center of the second steering roller is eccentric in a direction opposite to the eccentric direction of the first steering roller with respect to the center of the shaft. Photosensitive belt steering apparatus for a printing press, characterized in that installed. The method of claim 1, When meandering the photosensitive belt from the first steering roller side to the second steering roller, the long diameter outer circumference of the first steering roller and the short diameter outer circumference of the second steering roller are in contact with the photosensitive belt, In the meandering of the photosensitive belt from the second steering roller side toward the first steering roller, the short diameter outer periphery of the first steering roller and the long diameter outer periphery of the second steering roller are in contact with the photosensitive belt. A photosensitive belt steering apparatus for a printing press, wherein each of the first and second steering rollers is installed eccentrically on the shaft. The method of claim 1 or 2, wherein the drive means, A drive source mounted to the frame and having a rotational shaft driven to rotate; And a gear member formed across the rotation shaft and the shaft to transfer the rotational force provided from the driving source to the shaft.