JP2006044907A - Image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming device equipped with a paper delivery device capable of improving paper alignment by surely eliminating static electricity of both front and rear sides of paper in any paper type and size. <P>SOLUTION: This image forming device includes: a first static eliminator, which is provided close to the downstream side of the paper discharging roller pair in a direction perpendicular to a paper traveling direction, and also arranged on the upper face side in the paper traveling direction, a second static eliminator, which is provided on the downstream side of the first static eliminator in a direction perpendicular to the paper traveling direction, and also provided on the upper face side in the paper traveling direction, and a third static eliminator, which is provided on the upstream side of the paper discharging roller pair in a direction perpendicular to the paper traveling direction, and also arranged on the lower face side in the paper traveling direction. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a paper discharge device connected to a subsequent stage of an image forming apparatus such as a copying machine or a laser beam printer.

As is well known, the paper discharge device of the image forming apparatus discharges paper and considers post-processing such as bookbinding, so that the paper is not uneven in the paper advance direction and the paper advance direction (paper width direction). It needs to be aligned.
Therefore, conventionally, as shown in FIG. 2, the static electricity charged on the paper 1 discharged from the paper discharge roller pair 4 of the paper discharge device 2 of the image forming apparatus 3 is detected as the paper 1, the leading end of the first static eliminator 16 a and the paper. 1 and the front end of the second static eliminator 16b are removed, and the sheet 1 is placed on the sheet stacking table 6 by a rotating member 9 that presses the rear end of the sheet 1 on the sheet stacking table 6 in the vertical direction. (See, for example, Patent Document 1).

  However, in the above-described means, since the first static eliminator 16a and the second static eliminator 16b are arranged immediately after the pair of paper discharge rollers 4 and on the upper surface with respect to the paper 1, the lower surface of the paper 1 The static elimination effect on the side may be reduced. Therefore, when the static electricity removal of the paper 1 is incomplete, the rear end of the paper 1 pressed by the rotating member 9 on the paper stacking table 6 is again on the paper transport path (not shown) due to the static electricity remaining on the paper 1. ) And collided with the leading edge of the paper 1 discharged from the succeeding stage, leading to deterioration of paper jam and paper alignment.

  Even when the rear end of the sheet 1 does not float, it is difficult to ensure the alignment of the sheet 1 because the sheet 1 on the sheet stacking table 6 may move due to static electricity.

JP 2004-10240 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide a paper discharge device that avoids the above problems and realizes good alignment of paper discharged into the paper discharge device.

  In order to achieve the above object, in the present invention, a first static eliminator disposed near the downstream side of the paper discharge roller pair in a direction orthogonal to the paper traveling direction and on the upper surface side with respect to the paper traveling direction; A second static eliminator disposed on the downstream side of the first static eliminator in a direction orthogonal to the paper traveling direction and on the upper surface side with respect to the paper traveling direction, and a paper traveling upstream of the paper discharge roller pair. And a third static eliminator disposed on the lower surface side in the direction orthogonal to the direction and in the paper traveling direction.

  According to the present invention, it is possible to provide an image forming apparatus including a paper discharge device that can reliably remove static electricity from a paper and realize good paper alignment for any paper type and size.

  An embodiment of the present invention will be described below with reference to FIG.

  A pair of paper discharge rollers 4 provided in the paper discharge device 2 that feeds paper 1 fed from a pair of paper discharge rollers (not shown) provided in the image forming apparatus 3 to the next stage, and is supported so as to be movable up and down. A stack table 6 for stacking and storing sheets fed from the paper discharge roller pair 4, a table driving mechanism (not shown) for raising and lowering the stack table 6, a control device for controlling the table driving mechanism, and a sheet Paper guide 17 for introducing 1 to the downstream side in the paper traveling direction, and a first paper for reciprocating in the traveling direction of the paper 1 disposed on the downstream side in the paper traveling direction and aligning the leading ends of the paper 1 An alignment member 8, a sheet upper surface pressing roller 5 that presses the upper surface of the leading end of the sheet 1, and a second use for aligning the rear end of the sheet 1 disposed on the upstream side in the sheet traveling direction and discharged onto the stack table 6. A sheet trailing edge stopper 15 which is an alignment member, a rotating member 9 which is arranged above the stack table 6 and presses the upper surface of the trailing edge of the sheet 1 discharged onto the stack table 6 in a vertical direction, and is arranged in parallel with the sheet traveling direction. The third sheet alignment member 7 that reciprocates in the direction perpendicular to the traveling direction of the sheet 1 (the sheet width direction) and aligns the sheet 1, the stacked sheet upper surface detection means 10 that detects the uppermost position of the sheet, and the sheet discharge Near the downstream side of the roller pair 4, the first static eliminator 16 a arranged in a direction orthogonal to the paper traveling direction to remove static electricity from the paper 1, and orthogonal to the paper traveling direction downstream of the first static eliminator 16 a A second static eliminator 16b that further removes static electricity of the paper 1 provided in the direction, and a third that removes static electricity of the paper 1 disposed in the direction orthogonal to the paper traveling direction in the vicinity of the upstream side of the paper discharge roller pair 4. From the static eliminator 16c It is made. The stack table 6 is detachably provided on a table arm 11 that can be moved up and down. When a predetermined amount of sheets are stacked on the stack table 6, the stack table 6 is moved from the table arm 11 to the stack table 6. Care has been taken to allow removal and transportation by the operator.

  When the sheet 1 charged with static electricity is conveyed from the image forming apparatus 3 into the sheet discharge device, first, static electricity on the lower surface side of the sheet 1 is removed by the third static eliminator 16c. Next, when the paper is transported into the paper discharge device by the paper discharge roller pair 4, static electricity on the upper surface side of the paper 1 is removed by the first static eliminator 16 a. Finally, the first static eliminator 16a and the second static eliminator 16b disposed at a position where there is little electrical influence from the structure (not shown) of the first static eliminator 16a and the discharge roller pair 4 Residual static electricity that could not be removed by the third static eliminator 16c is removed. As a result, it is possible to prevent the rear end of the paper 1 stacked on the stack table 6 from floating on the paper transport path, and to prevent unevenness at the top of the paper 1 stacked on the stack table 6 due to residual static electricity. can do.

  Further, since the amount of biting between the sheet 1 fed out from the discharge roller pair 4 and the tip of the second static eliminator 16b is set to 1 to 3 mm, it is possible to reliably remove static electricity and the sheet. 1 can be quickly conveyed in the vertical downstream direction. As a result, it becomes difficult to form an air layer in the stacked paper, and good alignment of the paper can be achieved.

  Further, the second static eliminator 16b is provided on the paper guide 17 in a direction orthogonal to the paper traveling direction, and the angle formed with the paper 1 is set to 60 ° or less, so that the surface having the toner image is raised. In any paper discharge mode such as a paper discharge mode having a large upward curl for discharging toward the paper, reliable static electricity removal can be achieved, and good alignment of the paper can be maintained.

  In the present invention, the specific arrangement relationship regarding the biting amount (or gap amount) between the paper 1 and the tip of the third static eliminator 16c, the angle between the paper 1 and the tip of the third static eliminator 16c, etc. Although not specifically limited, it goes without saying that further static elimination effects can be expected by devising the arrangement in the same manner as the second static eliminator 16b.

  By attaching static eliminators on the upper side and the lower side in the direction orthogonal to the paper traveling direction, it can be applied to applications that require alignment of papers and in which static elimination is essential.

1 is a configuration diagram of a paper discharge device of an electrophotographic printing apparatus showing an embodiment according to the present invention. It is a block diagram of the paper discharge apparatus of the electrophotographic printing apparatus which shows one Example by a prior art.

Explanation of symbols

1 is a paper, 2 is a paper discharge device, 3 is an image forming device, 4 is a pair of paper discharge rollers, 5 is a paper upper surface pressing roller, 6 is a stack table, 7 is a third paper alignment member, and 8 is a first paper Alignment member, 9 is a rotating member, 10 is a loaded paper upper surface detecting means, 11 is a table arm, 12 is a motor, 13 is a power transmission belt, 14 is a drive shaft, and 15 is a second paper alignment member. 16a is a first static eliminator, 16b is a second static eliminator, 16c is a third static eliminator, and 17 is a paper guide.

Claims (5)

A pair of discharge rollers connected to a subsequent stage of the image forming apparatus and configured to send the sheet sent out from the image forming apparatus downstream;
A paper guide for guiding the paper downstream in the paper traveling direction;
A paper loading table for stacking and storing the paper;
A table drive mechanism for raising and lowering the paper stacking table;
A control device for controlling the table driving mechanism;
Upper surface detecting means for detecting the uppermost surface position of the paper;
A first paper alignment member disposed on the downstream side in the paper traveling direction above the paper stacking table and provided so as to be capable of reciprocating in the paper traveling direction of the paper discharged on the paper stacking table;
A second paper alignment member disposed on the upstream side in the paper traveling direction above the paper stacking table;
A pair of third paper alignment members provided so as to be capable of reciprocating in the paper width direction perpendicular to the paper traveling direction above the paper stacking table;
In an image forming apparatus provided with a paper discharge device having a drive mechanism for each paper alignment member,
A first static eliminator provided near the downstream side of the paper discharge roller pair;
A second static eliminator provided at the entrance of the paper guide disposed downstream of the first static eliminator;
An image forming apparatus comprising: a third static eliminator provided in the vicinity of the upstream side of the discharge roller pair.   2. The image forming apparatus according to claim 1, wherein at least one of the static eliminators is arranged in a direction orthogonal to a paper traveling direction and on a lower surface side with respect to the paper traveling direction. A first static eliminator disposed near the downstream side of the paper discharge roller pair in a direction orthogonal to the paper traveling direction and on the upper surface side with respect to the paper traveling direction;
A second static eliminator disposed on the downstream side of the first static eliminator in a direction orthogonal to the paper traveling direction and on the upper surface side with respect to the paper traveling direction;
3. The image according to claim 1, further comprising a third static eliminator disposed on the upstream side of the paper discharge roller pair in a direction orthogonal to the paper traveling direction and on a lower surface side with respect to the paper traveling direction. Forming equipment.   4. The biting amount between the sheet fed from the pair of paper discharge rollers and the tip of the second static eliminator is set to 1 to 3 mm and is in contact. Image forming apparatus. 4. The image forming apparatus according to claim 1, wherein an angle formed between the sheet fed from the pair of paper discharge rollers and the tip of the second static eliminator is 60 ° or less. 5.

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