JPS6236258A - Sheet-head adjustment for printing device - Google Patents

Abstract

PURPOSE:To feed a sheet free from disturbance by sending the fed sheet into a printing part by two transport means and discharging said sheet after printing and once retreating the nipped next sheet and again nipping and transporting said sheet. CONSTITUTION:The edge part of a sheet P sent out one by one from a feeding means is nipped between a platen 19 and pressure rollers 33 and 35. Then, the sheet P is discharged through reverse sending by reversely revolving. The sheet P is curved as shown by the dotted line in the figure between a transport roller 137 and the platen 19, and the top edge of the sheet P uniformly contacts with the platen 19. Then the sheet P is sent into a printing part 29 by normally revolving the platen 19, and then discharged after printing. The nipped next sheet P is discharged by reversely revolving the platen 19, and the similar treatment to the preceding is performed. Thus, the bending of the head part of the sheet P is prevented, and the sheet P is correctly resisted, and the sheet P after printing is correctly discharged.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a sheet cueing method for a printing device such as a printer or a typewriter, in which a sheet such as printing paper is set at the printing position of the printing device.

[Technical background of the invention]

Generally, when printing on a plurality of sheets of paper continuously using a printing device such as a printer or a typewriter, a paper feed unit that automatically supplies the paper is attached to the paper feed port of the printing unit.

Some paper feeding units are equipped with a drive source, but
Recently, in order to reduce costs, some printers do not have a driving source, but instead obtain driving force from a printing unit to rotate a paper feed roller and feed sheets one by one to the printing unit.

Further, the printing unit grips the supplied paper between a platen and a pressure roller, supplies it to a printing position, and prints with a head that reciprocates along the platen.

An example of a printing device that obtains the driving force for the paper feeding unit from the printing unit in this manner is disclosed in Japanese Patent Publication No. 58-6633.

In order to register the leading edge of the paper sent out by the paper feed roller, this printing device bends the paper by abutting the leading edge of the paper against the pressure contact between the platen and the pressure roller, and uses the stiffness of the paper to register the leading edge of the paper. are doing.

However, since the paper feed unit receives its driving force from the print unit, when the paper feed roller is rotating, the platen must also rotate. On the other hand, in order to register the leading edge of the paper sent out by the paper feed roller, if the platen rotates in the transport direction of the paper, the leading edge of the paper cannot be registered. For this reason, the platen is rotated in a direction opposite to the paper conveyance direction.

In other words, the paper sent out by the paper feed roller is brought into contact with the pressure roller between the platen and the pressure roller, which rotates in the opposite direction to the conveyance direction, and the paper is deflected to register the leading edge of the paper.Then, the platen is rotated in the normal direction. the paper is set in the print position.

[Problems with background technology]

However, because the paper is in contact with the press between the platen and the pressure roller, which rotate in the opposite direction to the conveyance direction,
Not only is the leading edge of the paper bounced and not registered accurately, but the leading edge of the paper is also easily folded.

Also, if you reverse the platen and pressure roller while paper is being ejected and start feeding and registering the next paper,
Paper that is being ejected is easily pulled in and hits the head, etc., causing damage to the paper.

[Purpose of the invention]

This invention prevents the leading edge of the paper from folding when register l~, and allows the leading edge of the paper to be reliably registered, and furthermore, even if the paper is moved back to register l~, the printed paper will not be drawn in. Seat 1 of the printing device without
The purpose is to obtain a cueing method.

[Summary of the invention]

In order to achieve the above-mentioned object, the present invention is directed to a first conveying means such as a platen and a pressure roller after a sheet is sent out by a feeding means such as a paper feeding roller after a sheet is discharged by a sheet discharging means such as a sheet discharging roller. The sheet held between the sheet and the second conveyance means is once retreated and discharged,
Thereafter, the sheet is rotated between the first conveying means and the second conveying means.
The paper is held between the paper and the conveying means of the paper and is fed to the printing position.

[Embodiments of the invention]

Two embodiments of the present invention will be described below with reference to the drawings.

The printing device of this embodiment includes a printing unit 3 as shown in FIGS. 1 and 2 and a paper feeding unit 1 as shown in FIG.
01.

First, the printing unit 3 has a structure as shown in FIGS. 1 to 4.

As shown in FIG. 1, a frame 9 is provided inside the cover 7 of the printing unit 3, and the platen shaft 13
is rotatably supported. A platen knob 15L and a gear 17 are attached to the left side of the platen shaft 13, a platen 19 is attached to the center, and a gear 21 and a platen knob 15R are attached to the right side.

Further, a motor 23 for driving the platen 19 is attached to the side portion 9L of the frame 9, and the driving force of this motor 23 is transmitted to the gear 17 via gears 24 and 25.

Further, as shown in FIG. 2, guide rods 26, 28 are provided parallel to the platen 19. A head carriage 27 is attached to these guide rods 26, 28 so as to be able to reciprocate, and the head carriage 27 is driven laterally along the guide rods 26, 28 by a drive device (not shown). .

The print head 2 is mounted on the head carriage 27 as shown in FIG.
9. The tip guide 30 is attached, and the ribbon cassette 34 is detachable.

Furthermore, as shown in FIGS. 2 and 3, around the platen 19 are pressure rollers 33, 35 arranged in two rows of platen guides 31, a paper pail roller 37 that presses the paper against the platen 19, a platen cover 39, A pair of coupling shafts 41 for coupling the paper feeding unit 101 to the printing unit 3 and the like are provided.

The pressure rollers 33, 35 are shown in FIGS. 1 and 3.
By rotating the pressure lever 43 shown in the figure about the shaft 42, the roller 44 rotates the arm 46 attached to the shaft 45, the guide 31 rotates about the shaft 45, and the platen 19 is rotated. Pressure is applied to or released from pressure. Note that the arm 46 is attached to the roller 4 by a spring 48.
It is energized to 4.

Further, the paper pail roller 37 is connected to the vapor pail lever 4
By rotating the arm 51, the arm 51 is rotated about the shaft 49, and the arm 51 is brought into or out of pressure contact with the platen 19.

Note that a cover 53 can be opened and closed above the head carriage 27, and the ribbon cassette 34 can be replaced in the open state.

The paper feed/discharge port 5 of the printing unit 3 configured as described above has a paper feed unit 10 as shown in FIGS.
1 is installed.

This paper feeding unit 101 has side frames 103 on both sides.
(Only one side frame is shown in the figure.) It has an arc-shaped support portion 105' that engages with the coupling shaft 41.

Further, a lock lever 10 is provided on the outside of the side frame 103.
7 is pivotally supported at its intermediate portion by a shaft 109. This lock lever 107 fixes the paper feeding unit 101 to the coupling shaft 41 and includes a retaining portion 111 that engages with the coupling shaft 41.

Shafts 113 and 115 are attached to the rear of the side frame 103, and a guide 117 bent in an N-shape is attached. A paper feed frame 119 is detachably attached to the back of the guide 117. Further, a paper feed tray 121 is attached to the shaft 115, and rotates via a crank 125 when a set lever 123 is rotated, and a side plate 127 is slidable, so that paper of different sizes can be handled. ing.

A separation lever 131 is rotatably attached to the outside of the side plate 127 by a shaft 133 and has a separation claw 129 that separates the stacked sheets P one by one during feeding.

A paper feed roller 137 is attached to a shaft 135 supported by the side frame 103 above and in front of the paper feed table 121 .

A manual feed guide 139 and a guide 141 are provided in front of the paper feed tray 121 and a guide 141 is provided opposite to this guide 139 to guide the paper P fed by the n1 paper feed roller 137 to the guide 117.
and 139, and also pass the manual paper through the guide 139.
and 141 to lead between the platen 19 and the platen guide 31.

Note that a paper ejection frame 143 is detachably attached to the manual feed guide 139.

A paper discharge roller 147 is attached to a shaft 145 above the guide 141, and a gear 149 is attached to one end and a sixth roller is attached to the other end.
A gear 151 is attached as shown in the figure. gear 149
A gear 153 is rotatably supported by a shaft 155 between the gear 21 and the gear 21 to connect the two.

Further, a paper ejection guide 157 is rotatable about a shaft 159 facing the paper ejection roller 147 .

As shown in FIG. 6, a gear 161 that meshes with a gear 151 and a gear 165 that meshes with a gear 163 are attached to the shaft 109.

Gear 163 is supported by shaft 167 and meshes with gear 169.

This gear 169 has a protrusion 171 inside and is supported by a shaft 175 together with a gear 173 as shown in FIG. A vibrator 177 into which a shaft 175 is inserted is attached to the gear 173, and a coil spring 179 is fitted into the circumferential surface of the vibrator 177. Note that this coil spring 179 is wound clockwise from the inside to the outside.

As shown in FIG. 8, a stop cam 183 having two protrusions 181 is fitted into the circumferential surface of the coil spring 179, and one end of the coil spring 179 is fixed thereto.

Further, a vibrator 185 is attached to the gear 169, a shaft 175 is inserted into the vibrator 185, and the vibrator 185 is inserted into the coil spring 179.

That is, a spring clutch is interposed between gears 169 and 173, and a stop cam 183 is attached to this spring clutch.

A gear 187 is attached to the shaft 135, and this gear 187
is meshed with gear 173.

On the other hand, a stop lever 189 that engages with a protrusion 181 of a stop cam 183 is rotatably supported by a shaft 191 and biased downward by a spring 193.

In the above configuration, this printing device operates as follows.

As shown in FIG. 5, set the paper P on the paper feed tray 121,
The set lever 123 is rotated to rotate the paper feed table 121 and press the paper P against the paper feed roller 137.

In such a state, when a print command is issued, the fourth
The slider carriage 27 shown in the figure moves from the left end home position to the center side and waits for paper to be supplied.

Further, the motor 23 shown in FIG. 1 is driven to rotate as shown in FIG. 9, and the platen shaft 13 shown in FIG. 5 is rotated clockwise. Therefore, the gear 149 also rotates clockwise via the gear 21.153. Therefore, the gear 151 shown in FIG. 6 attached to the other end of the shaft 145 of the gear 149 rotates counterclockwise (rotates in the same direction as the gear 149).

This rotation of gear 151 causes gears 161 and '165 to rotate clockwise, and gear 163 meshing with gear 165 rotates to the left. This causes the gear 169 to rotate clockwise. Therefore, the vibrator 177 rotates. At that time, as shown in Figure 8, spring 1
Projection 1 of stop cam 183 holding one end of 79
81 is locked by the stop lever 189, the vibrator 185 idles inside the spring 179. When the gear 169 rotates further and the protrusion 171 pushes up the stop lever 189, the stop cam 183 is unlocked, the vibrator 185 and the spring 179 are connected, and the vibrator 177 connected to the spring 179 rotates. . For this reason, the gear 17 fixed to this vibrator 177
3 rotates clockwise.

As a result, the gear 187 rotates to the left, so that the paper feed roller 137 shown in FIG. 5, which is attached to the shaft 135, rotates to the right. For this reason, the paper P is sent out, the paper P gets caught on the separation claw 129 and bends, and when it exceeds the elastic limit, it bounces and becomes 1
The paper is separated into sheets and enters between the platen 19 and the pressure roller 33 along guides 117 and 139.

Then, as shown in FIG. 10, the motor 23 is stopped after a predetermined amount of M1 rotations that will cause the paper P to be gripped by the platen 19 and the pressure rollers 33, 35. Note that if there is a discharged paper, the paper P has come off the paper discharge roller 147 at this point as shown in FIG. Thereafter, the motor 23 is reversely rotated by a predetermined amount M2.

Due to the stiffness, the reversely rotating platen 19 moves the paper P backward, and the paper P is ejected from the platen 19 and the pressure roller 33.

As the platen shaft 13 rotates in the opposite direction, the gear 169 also rotates in the opposite direction. As a result, the pipe 185 also rotates in the opposite direction, but the spring 179
Since the pipe 185 is rotated in the opening direction, the rotational force of the pipe 185 is not transmitted to the pipe 177. Therefore, platen 1
Even if 9 is rotated in the reverse direction, the gear does not rotate and the paper feed roller 137 also does not rotate.

In such a state, when the paper P is ejected from between the platen 19 and the pressure roller 33, the paper P is pushed against the platen as shown by the broken line in FIG. 19 and paper feed roller 137
- Due to the stiffness of the paper P, the leading edge of the paper is registered at the pressure contact portion between the platen 19 and the pressure roller 33.

Then, the motor 23 is rotated in the normal direction again, the paper P is again gripped by the platen 19 and the pressure roller 33.35, and the paper P is fed by a predetermined amount. When the motor 23 has rotated by a predetermined amount M3, that is, at the printing start position of the paper P, The motor 23 is temporarily stopped, and the print head 29, which was located at the center, is returned to its home position on the left by movement of the carriage 27, and printing is started. -The platen rotates by one line each time printing of each line is completed.

The printed paper P is passed through the paper ejection roller 35 and the paper ejection guide 157.
It is discharged through the gap between the

The leading edge of the paper P to be discharged rises along the manual feed guide 139 and the paper discharge frame 143, and when the trailing edge of the paper P is discharged, the trailing edge of the paper is supported by the recess of the guide 141 and placed in the paper discharge stacker. be accommodated.

At this point, the protrusion 171 comes off the stop lever 189 and the tip of the lever 189 falls onto the circumferential surface of the stop cam 183, and while it continues to rotate, the paper feed roller 137 feeds out the paper P. When the tip of the stop lever 189 engages with the protrusion 181 of the stop cam 183, the pipe 185 idles within the spring 179, and the gear 173 stops rotating.

When the projection 171 pushes up the lever 189 again, the paper is fed. This cycle is repeated, and the paper r is automatically sent out at regular intervals.

According to the above embodiment, the following effects can be obtained.

(1) After the paper sent out by the paper feed roller 137 is caught between the platen 19 and the pressure roller 33.35, the paper is moved backward to form a bend and register. When gripping, the platen 19 and pressure roller 33 are rotating in the conveyance direction.
Since the paper is fed between the two, the paper is smoothly gripped and the leading edge of the paper is not easily folded.

Furthermore, since registration is performed by spitting out the paper held in the mouth to form a sag in the paper, the registration can be performed reliably.

(2) As shown in Figure 10, the paper discharge roller 147
After finishing discharging the paper P, the paper P sent out by the paper feed roller 137 and held between the platen 19 and the pressure roller 33.35 is once retreated and ejected, and then the paper P is transferred again between the platen 19 and the pressure roller 33.35. Since the platen 19 is held between the paper rollers 33 and 35 and sent to the printing position, the platen 19 is reversed and the paper is fed to the paper ejection roller 147.
Even if the rotation is reversed, the ejected paper will not be drawn in by the ejecting roller 147, and the ejected paper will not be damaged.

(3) After the motor 23 has rotated by a predetermined amount M1 after the motor 23 starts rotating, the motor 23 is rotated in the opposite direction to register the paper P, so that the paper can be ejected without the need for a paper edge detection means such as a sensor; Can be resisted.

Therefore, this cueing method can be applied even to a printing device in which the printing unit 3 is not provided with a sensor for detecting the leading edge of the paper held between the platen 19 and the pressure rollers 33, 35.

That is, cueing can be performed without depending on the format of the printing unit 3.

[Modified example]

The present invention is not limited to the above-mentioned embodiment, and for example, the following modifications are possible.

(1) In the above embodiment, a printing device is shown in which the printing unit and the paper feeding unit are detachable, but the printing unit and the paper feeding unit may be integrated.

(2) In the above embodiment, after the platen 19 rotates and feeds the paper by the paper feed roller 137, the motor 23 is rotated by a predetermined amount M2 after rotating by a predetermined amount M1, and the pressure roller 3
3.35 and platen 19, or when a sensor is installed at the tip of pressure roller 35 and detects the leading edge of the paper, platen 19 may be reversed.

(3) As shown in FIG. 11, two or more pressure rollers 203.20
5.207 may be pressed against the platen 209.

In this case, the paper may be held up to the pressure roller 205 and then retreated to be discharged, or may be held up to the pressure roller 207 and then discharged.

(4) In the above embodiment, the platen 19 is driven and the pressure rollers 33, 35 are driven; however, as shown in FIG. good.

Also, the platen 209 and pressure rollers 203 and 205
．． 207 may be driven together.

(5) This invention is based on the platen 211 as shown in FIG.
is fixed, and the present invention can also be applied to a printing device in which paper guided by a guide 213 is fed to a printing position by rollers 215, 217, 219, and 221.

(6) In this invention, as shown in FIG. 13, the guide 223.
225 guides the paper through rollers 227.22
9.231.233 can also be applied to a printing device that supplies the printing position to the platen 235.

〔Effect of the invention〕

As explained above, according to the present invention, the stacked sheets are fed out one by one by the feeding means, and the fed sheets are held between the first conveying means and the second conveying means which are pressed together. In the printing device, the sheet is sent to the printing position and printed, and then ejected by the ejecting means. The sheet held between the conveyor and the conveyance means is once retracted and discharged.
Thereafter, this sheet is transferred again to the first conveying means and the second conveying means.
Since the leading edge of the paper is not easily bent during registration, the leading edge of the paper can be reliably registered, and the leading edge of the paper can be reliably registered. Seats 1 to 1 of the printing device where the printed paper will not be drawn in even if the printer is moved backwards.
You can get a cue method.

[Brief explanation of the drawing]

Figures 1 to 4 are diagrams showing the configuration of the printing unit.
2 is a cross-sectional view of the printing unit, FIG. 2 is a longitudinal sectional view of the printing unit, FIG. 3 is a sectional view showing a pressure roller pressure contact mechanism, and FIG. 4 is a view showing the structure around the print head. Figures 5 to 8 are diagrams showing the configuration of the paper feeding unit.
Figure 6 is a longitudinal cross-sectional view showing the overall structure of the paper feed unit, Figure 6 is a view showing the drive transmission mechanism provided on the left side frame, and Figures 7 and 8 are cross-sectional views showing the structure around the spring clutch. It is a diagram. FIG. 9 is a timing chart for explaining the operation, and FIG. 10 is a diagram for explaining the operation. FIGS. 11 to 13 are diagrams showing modifications of the present invention. 3...Print unit 19...Platen 29--Print head 3mm 35.Shaft...Branch roller 101...Paper feed unit 137...Paper feed roller 1
47-----・Paper ejecting roller 77 Fig.'° Fig. 7 弼/l 72 fig. ψ1ノ3 Hill convex

Claims (5)

[Claims] (1) The stacked sheets are fed out one by one by the feeding means, and the fed sheets are held between the first conveying means and the second conveying means that are pressed together and sent to the printing position for printing. In a printing device in which the sheet is then ejected by a discharging means, after the discharging means finishes discharging the sheet, the sheet is sent out by the feeding means and held between the first conveying means and the second conveying means. The printing device is characterized in that the sheet is once retreated and discharged, and then the sheet is again held between the first conveying means and the second conveying means and sent to the printing position. How to cue the sheet. (2) In the sheet cueing method for a printing device according to claim 1, the first conveyance means is a platen, and the second conveyance means is a pressure roller. How to cue the sheet. (3) In the sheet cueing method for a printing device according to claim 1, the first conveying means and the second conveying means are rollers that are pressed against each other. How to cue the sheet. (4) In the sheet cueing method for a printing device according to claim 1, the first conveying means is driven by a drive source, and the second conveying means is driven by the operation of the first conveying means. A sheet cueing method for a printing device characterized by being driven. (5) In the sheet cueing method for a printing device according to claim 1, the second conveying means is driven by a drive source, and the first conveying means is driven by the operation of the second conveying means. A sheet cueing method for a printing device characterized by being driven.