JPH03200981A - Accelerating mechanism for retreating recording paper of printer using continuous recording paper - Google Patents

Abstract

PURPOSE:To securely retreat continuous from a photosensitive drum in printing stand-by mode by arranging a recording paper guide member on the transfer surface side of the continuous recording paper and providing a flocked member on the recording paper conveyance path side of a recording guide member so that the filling tip abuts on the continuous recording paper. CONSTITUTION:A brush 14 with specific width as the flocked member is mounted on the side of the recording paper conveyance path at the end part of an upper guide 13U on the side of a transfer part 7 over the entire width- directional area of fan fold paper 20. In the printing stand-by mode, the fan fold paper 20 is stopped from being conveyed and released from being pressed against the side of a photosensitive drum 1, and the constant-speed conveyance is stopped abruptly, so that the fan fold paper 20 slacks between a photosensitive drum 21 and a corona charger 71 because of the inertia. The filling member of the brush 14 at this time is released from being tensed when the fan fold paper 20 slacks and returns to its straight state, thereby retreating the fan fold paper 20. Consequently, the continuous paper can securely be retreated from the photosensitive drum in the printing stand-by mode.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention forms an image on continuous recording paper using electrophotography, and is configured such that a transfer charger is retracted from a transfer action position during printing standby. The present invention relates to a printer's recording paper evacuation promotion mechanism.

[Prior Art] Conventionally, a photoreceptor on the surface of a photoreceptor drum is exposed to light to form an IT, toner is attached to this latent image and developed, and the toner is transferred to recording paper and fixed by a fixing device. Image forming apparatuses that use photography are known,
One of them is an electrophotographic printer that prints information on folded continuous paper with perforations, so-called fan-hold paper, which is the same as that used in conventional line printers.

The fan-hold paper is configured so that it can be cut at the perforations along the boundaries between pages, and is supplied in a stacked state that is alternately folded in opposite directions at the perforations.

By the way, in printers that use continuous paper as recording paper,
Printing must start at a fixed position from the perforation of the continuous paper (i.e., the top edge of the page), or in electrophotography, the exposure, development, and transfer units are arranged around the photosensitive drum. The exposed area of the photosensitive drum reaches the transfer position as the photosensitive drum rotates, and the transfer is performed, so it is continuous at the start of printing. In order to match the exposure start portion to a fixed position from the perforation of the paper (that is, to start printing at a fixed position from the perforation), the photosensitive drum must be moved (rotated) relative to the continuous paper before printing starts. ) to adjust the print start position (so-called cueing).

Here, when starting this, 1. If the continuous paper remains in contact with the photoconductor drum (transfer operation state), the photoconductor on the surface of the photoconductor drum will be damaged or worn out, shortening the life of the photoconductor drum.
Further, there is a problem in that the continuous paper is stained with residual toner on the surface of the photosensitive drum (toner adheres to striped contact areas along the length of the photosensitive drum, resulting in so-called black streaks).

For this reason.

The present applicant has previously proposed a system in which the transfer charger is configured to be separable from the photosensitive drum, and the transfer charger is retracted from the transfer action position (separated from the photosensitive drum) during printing standby. Note that this retraction of the transfer charger is performed in synchronization with the stoppage of conveyance of the continuous paper at the end of printing.

[Problems with the Prior Art] However, even if the transfer charger is separated from the photosensitive drum and the conveyance of the continuous paper is also stopped at the end of printing (during standby for printing) as described above, the conveyance of the continuous paper is still difficult. Because this is carried out by a transport mechanism installed ahead of the photosensitive drum in the transport direction, the continuous paper, which was being transported at a constant speed until just before the end of printing, cannot be stopped instantaneously, and its inertia causes it to move forward slightly. However, even though the transfer charger is retracted due to loosening at the position corresponding to the photosensitive drum, the essential continuous paper does not retract and continues to contact the photosensitive drum, resulting in smearing (black streaks occur) when printing resumes. There was a problem with this.

This problem is particularly significant when the continuous paper located at a position adjacent to the photosensitive drum when printing is stopped (when the continuous paper is stopped) is folded in a direction that projects toward the photosensitive drum (so-called mountain folding).

[Object of the Invention] In view of the above-mentioned circumstances, the present invention provides a recording paper retraction promotion mechanism for a printer using continuous recording paper, which can reliably retract and separate the continuous paper from a photosensitive drum during printing standby. purpose.

[Means for Solving the Problems] In order to achieve the above object, the recording paper evacuation promotion mechanism of a printer using continuous recording paper according to the present invention has a mechanism for promoting paper retraction on the transfer surface side of the continuous recording paper leading to the transfer site with the photosensitive drum. In addition to disposing a recording paper guide member, a flocked member is provided on the recording paper transport path side of the recording paper guide member so that the bristles thereof come into contact with the continuous recording paper during transfer.

[Embodiments of the invention] Next, the present invention will be explained in detail based on one drawing.

FIG. 1 shows a laser beam printer device that uses fan-hold paper, which is continuous paper, as recording paper, and prints character information input from a computer or the like on fan-hold paper 20 using an electrophotographic method. be.

゛Around the photosensitive tram l, there is a toner cleaning section 2.
A static eliminating section 3, a charging section 4, a scanning optical system 5 that guides a laser beam onto a photosensitive drum, a developing section 6, and a transfer section 7 are arranged in a predetermined order along the rotational direction of the drum, respectively. 8 is disposed in front of the fan-hold paper 20 in the transport direction, and a tractor 9 is a transport mechanism that transports and drives the fan-hold paper 20 during the transport path of the fan-hold paper 20 from the photosensitive drum l to the fixing unit 8. It is configured by arranging.

While the photosensitive drum 1 is rotationally driven (sub-scanning), its surface is main-scanned (exposed) in the direction of the rotation axis with a laser beam from the scanning optical system 5 to form an electrostatic latent image, and this latent image is developed. At step 6, toner is attached and developed as a toner image),
At the same time, the toner image is transferred onto the fan-hold paper 20 by the transfer section 7.

The fixing section 8 fixes the toner image on the fan-hold paper 20 and outputs it. The tractor 9 has a tractor belt 91 having a protrusion that fits into a feed hole at the side end of the fan-hold paper 20, and arranges the tractor belt 91 so that its orbit matches the conveyance path of the fan-hold paper 20. It is possible to rotate the photosensitive drum 1 at a speed equal to the circumferential rotational speed of the photosensitive drum 1 using a DC motor or the like.

As shown in an enlarged view in FIG. 2, the transfer unit 7 transfers a corona-charged square 71 to a fulcrum 73 at both ends of the bracket 11 erected on the chassis lO of the laser beam printer.
The photosensitive drum 1 is held parallel to the photosensitive drum l so as to be retractable by an arm 72 which is swingably supported by the arm 72 . The arm 72 is biased to swing by a spring 75 interposed between the lower surface of the arm 72 and the chassis 10, and is brought to a predetermined position where the corona charge @71 held by the arm 72 is transferred to the photosensitive drum l. ing.

Further, a pressing member 76 having a semicircular cross section is attached to the arm 72 on the tip side (the side where the fan hold paper 20 is introduced) from the position where the corona charger 71 is held, and when the corona charger 71 is in the transfer operation position, The pressing member 76 presses the fan-hold paper 20 toward the photosensitive drum l to bring it into close contact with the transfer position.

On the same fulcrum 74 on which the arm 72 is pivoted, a paper presser 74 having a lever portion 74A protruding from its lower surface is pivotably supported, and the chassis lO of the laser beam printer device is , a slide plate 12 is provided so as to be slidable in a direction parallel to the conveyance direction of the fan-hold paper 20 by a drive means (not shown).

Then, the slide plate 12 is attached to the fan hold paper 2.
When the fan hold paper 20 is slid in the direction of ejection, the operation section 12 vertically formed at the end of the fan hold paper 20 on the introduction side
A operates a pin 77 installed horizontally on a lever part 74A of a paper presser 74 to swing the paper presser 74 clockwise in the figure, and the swing of the paper presser 74 causes the arm 72 to swing.
is driven to swing against the biasing force of the spring 75, and the third
As shown in the figure, the corona charger 71 is retracted downward in the figure from the transfer position.

On the side where the fan-hold paper 20 is introduced from the transfer section 7, upper and lower guides 13U and 13D are arranged as recording paper guide members separated by a predetermined distance, and the fan-hold paper 20 is placed between the upper and lower guides 13U and 130. The paper passes through a recording paper conveyance path 13 formed in , and reaches the transfer section 7 .

The upper and lower guides 13U and 13D are formed so that their introduction sides face downward at a predetermined angle, and are bent upward toward the transfer section 7 midway. or.

Recording paper conveyance path 13 at the end of the upper guide 13U on the side of the transfer section 7
A brush 14 of a predetermined width as a flocking member is attached to the side of the fan-hold paper 20 over the entire width thereof.

The brush 14 is a so-called brush in which bristles of a predetermined diameter and a predetermined length are densely planted and can be bent and deformed with extremely weak force.
It is provided so as to protrude into the recording paper transport path 13 at the tip.

According to the above configuration, during printing when the corona charger 71 is in the transfer action position, the recording paper conveyance path 13 formed by the upper and lower guides 13U and 13D as shown in the second figure
The fan-hold paper 20 that passes through the inside and reaches the transfer section 7 is pushed up toward the photosensitive drum l by a pressing member 76 on the front side of the corona charger 71, and its upper surface is attached to the exit portion of the photosensitive tram l and the upper guide 13U. It comes into contact with the brush 14 that has been touched. As a result, the bristles of the brush 14 are pressed upward by the fan-hold paper 20, and the fan-hold paper 20 is brought forward in the transport direction.

When printing is finished (standby for printing), the fan hold paper 20
At the same time, the slide plate 12 is slid by a drive means (not shown) in the discharge direction of the fan-hold paper 20, the arm 72 is driven to swing, and the corona charger 71 is retracted from the transfer position. At this time, the fan hold paper 20 is moved between the photosensitive tram l and the corona charger 71 due to the release of the pressure on the photosensitive drum l side by the pressing member 76 and the inertia caused by the sudden stop of conveyance at a constant speed. There is slack between the two.

At this time, there is no problem if the fan-hold paper 20 loosens toward the corona charger 71, but if it loosens toward the photosensitive drum l, the corona charger 71 is retracted but the fan-hold paper 20 remains in contact with the photosensitive drum l. Therefore, there is a risk that this contact area will become dirty (black streaks will occur) when printing is resumed.

Here, the brush 14 has one bristle member and a fan hold paper 20.
Since the fan-hold paper 20 is in contact with the fan-hold paper 20, its frictional resistance prevents the inertial movement of the fan-hold paper 20 at the time of stopping and prevents the fan-hold paper 20 from loosening as much as possible. The fan hold paper 20 returns to the upright state as shown in the third figure.
The slack is regulated to be on the corona charger 71 side. That is, the bristles of the brush 14 are easily bent by the fan-hold paper 20 under tension during transfer, but when the fan-hold paper 20 is loosened, the tension is released and the bristles return to the upright state. This acts to evacuate the fan hold paper 20. Moreover, the brush 14 is
Since the elastic restoring force of a single book is made up of a plurality of bristles implanted, the fan hold paper 20 is pressed evenly depending on the slack state of the fan hold paper 20 to ensure that the elastic return force is extremely weak. It can be evacuated.

It has been confirmed through experiments that the coefficient of friction between the bristles and the paper is optimal in the range of 0.9 to 1.1, and in fact, the brush 14 is made of acrylic resin and has a height of 3-1. When 308 bristles were implanted per inch and an experiment was conducted as a vergence ms, good results were obtained.

[Effects of the Invention] As described above, according to the recording paper evacuation promotion mechanism of a printer using continuous recording paper according to the present invention, the direction of loosening of the continuous paper is regulated by the elasticity (returning force) of the brush bristles. This allows the continuous paper to be reliably moved away from the photosensitive drum during printing standby.

[Brief explanation of drawings]

FIG. 1 is a side view showing a schematic configuration of a printer equipped with an embodiment of a recording paper evacuation promotion mechanism for a printer using continuous recording paper according to the present invention, FIG. FIG. 3 is a diagram showing a state in which the transfer charger is retracted from the state shown in FIG. 2. l... Photosensitive drum 13... Recording paper conveyance path 13υ... Upper guide (recording paper guide member) 14-...
Brush (flocking material)

Claims (1)

[Claims] In a printer that forms an image on continuous recording paper using electrophotography and is configured such that a transfer charger retreats from a transfer position during printing standby, a transfer site with a photosensitive drum is provided. A recording paper guide member is disposed on the transfer surface side of the continuous recording paper, and the bristles of the recording paper guide member are placed on the recording paper conveyance path side so that they come into contact with the continuous recording paper during transfer. A recording paper evacuation promotion mechanism for a printer using continuous recording paper, characterized in that a flocking member is provided.