JPS6236257A - Sheet-head adjustment for printing device - Google Patents

Abstract

PURPOSE:To correctly adjust the head port of the sheet sent out from a feeding means by nipping said sheet between two transport means and once retreating said sheet and sending out said sheet again by the feeding means and nipping said sheet by the transport means. CONSTITUTION:The edge part of a sheet P sent out one by one from a feeding roller 58 is nipped between a platen 19 and a pressure roller 33. Then, the sheet P is discharged by reversely revolving the platen 19. The sheet P is curved as shown by the dotted line in the figure by the pushing of the feeding roller 58 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 consisting of a printing head 29, guide 30, etc. by normally revolving the platen 19, and the sheet P is once brought into stop, and printing of one line is carried out, and then the operation for the next line is carried out. Therefore, the bending of the head part of the sheet P is prevented, and the sheet P is correctly resisted, and correct printing is performed.

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 in which the driving force for the paper feed unit is obtained 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 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 is rotated in the conveyance 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, since the paper is pressed against the pressure contact between the platen and the pressure roller, which rotate in the opposite direction to the conveyance direction, the leading edge of the paper is flipped and not only is it not registered accurately.
The leading edge of the paper is easily bent.

Furthermore, when the platen is reversed after registration and the paper is fed to the printing position, it is difficult to hold the paper that was flipped during registration, and the printing position is likely to shift.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet cueing method for a printing device in which the leading edge of the paper is not easily bent during registration, the leading edge of the paper can be reliably registered, and the paper can be smoothly fed to the printing position. do.

[Summary of the invention]

In order to achieve the above object, the present invention grips a sheet sent out by a paper feed means such as a paper feed roller between a first conveyance means such as a platen and a second conveyance means such as a pressure roller. After that, this sheet is once retracted and discharged, and then the writing sheet is sent out by the paper feeding means, so that 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]

An embodiment of the 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 feed unit 1 as shown in Fig. 5.
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 a platen shaft 13 is rotatably supported on both sides 9L and 9R of the frame 9 via bearings 11L and IIR. There is. A platen knob 15L and a gear 17 are placed on the left side of the platen shaft 13, and a platen 1 is placed in the center.
9 is attached, and a gear 21 and a platen knob 15K are attached to the right side.

Further, a motor 23 for driving the platen 19 is attached to the side portion 9R of the frame 9, and the driving force of this motor 23 is transmitted to the gear 21 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 in the compensation direction 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. A tip guide 30 is attached, and a ribbon cassette 34 is detachable.

Further, 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, and a paper plate cover. 39 etc. have been established.

The pressure rollers 33, 35 are shown in FIGS. 1 and 3.
By rotating the pressure lever 43 shown in the figure around the shaft 42, the roller 44 rotates the arm 46 attached to the shaft 45, and the guide 31 rotates around the shaft 45 to press against the platen 19. The pressure may be removed or the pressure bond may be released. Note that the arm 46 is urged against the roller 44 by a spring 48.

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

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 1 as shown in FIGS.
01 is installed.

As shown in FIG. 8, this paper feeding unit 101 supports a paper feed stacker 54 that accommodates stacked sheets of paper P by a pair of left and right side plates 56L156R as shown in FIG. P is sent out to the platen 19 side.

The side plate 56L has a housing portion 57 and a flange 59 as shown in FIG.
, a support portion 61 of a support shaft 65 that supports the paper feed stacker 54
It is equipped with such things as

Further, as shown in FIG. 9, the housing portion 57 includes a shaft hole 69 that supports a rotating shaft 67 to which a paper feed roller 58 is attached, and a support shaft that supports a manual feed guide 71 provided in front of the paper feed roller 58 from above and below. A shaft hole 77.79 is provided which holds 73.75. Although not shown, a confirmation window for confirming the home position of the drive transmission mechanism 55 of the paper feed roller 58 is provided.

A drive transmission mechanism 55 is housed in the housing portion 57, as shown in FIGS. 9 and 10.

First, a gear 107 that meshes with the gear 17 of the printing unit 3 is attached to the support shaft 81 .

Further, the rotating shaft 108 to which the paper discharge roller 241 is attached has a gear 109 that meshes with the gear 107, and the supporting shaft 85 has a gear 1.
A gear 111 that meshes with 09 and a gear 113 smaller than this gear 111 are attached. Further, a gear 115 that meshes with the gear 113 is attached to the support shaft 87, and a gear 119 that meshes with the gear 115 is attached to the support shaft 89.

A ratchet pawl 123 rotating about a shaft 121 and a leaf spring 125 biasing the ratchet pawl 123 toward the support shaft 89 are attached to the inside of the gear 119. Then, a cam 12 that restricts the movement of the pawl 123 to the ratchet 1
7 are attached to pins 91, 93, and 95. In addition,
A color display indicating the home position is provided at one location on the outside of the gear 119, corresponding to the confirmation window.

Furthermore, a gear 129 shown in FIG. 10 is attached to the support shaft 89. A ratchet 131 shown in FIG. 9 is attached to the gear 119 side of this gear 129. Shaft hole 69
The gear 13 meshes with the gear 129 via the support shaft 67.
3 is provided.

The drive transmission mechanism 55 configured in this way is covered with a cover plate 147 as shown in FIG.

A chucking part 99 is attached below the housing part 57 that houses the drive transmission mechanism 55, as shown in FIG.

This chucking portion 99 includes a fitting portion 135 that fits into the bearing 11L shown in FIG.

On the other hand, the side plate 56R includes a flange 165, support portions 169, 171, 173, and a first
A chucking portion similar to the chucking portion 99 that fits into the bearing 11R shown in the figure is provided.

Between the side plates 56L and 56R configured as above,
A support shaft 65.73.75 and a conveyance guide 134 are attached to provide rigidity, and a rotation shaft 67.10
8 is rotatably attached.

The support shaft 65.75 has a bottom plate 1 having an N-shaped side surface.
95 are attached via support plates 197 and 199.

This bottom plate 195 includes a back surface section 195A located at the rear, a stopper section 195B that holds the leading edge of the paper, a guide section 195C that guides the paper forward, and a support section 19 shown in FIG.
It is equipped with 5D. The rear part 195AG:; is the paper feed frame 20 that supports the rear of the paper on the paper feed stacker 54.
1 is removable.

Further, a set lever 202 that moves the paper feed stacker 54 up and down is rotatably attached to the support portion 195D via a shaft 204. This set lever 202 is a lever part 20
2A and a cam portion 202B are integrally provided. A click spring 206 is installed between the support portion 195D and the cam portion 202B.

A paper feed stacker 54 is rotatably attached to the support shaft 65. As shown in FIG. 8, this paper feed stacker 54 is divided into a left stacker 54L having a side plate 203L and a right stacker 54R having a side plate 203R, and the left stacker 54L is fixed in the axial direction.
The right stacker 54R is movable in the axial direction.

On the back side of the left stacker 54L, as shown in FIG. 6, there is a pin 211 that engages with the cam portion 292B of the set lever 202.
A frame 213 is attached which has an arm 213L attached thereto and a spring attachment portion 213R shown in FIG. A spring 215 is attached between the spring attachment portion 213R and the back surface portion 195A, and always urges the paper feed stacker 54 toward the paper feed roller 58 side.

A support shaft 217 is provided on the outside of the side plates 203L, 203R, and separation levers 219L, 219R are attached through attachment holes 221.

The separation levers 219L and 219R include a separation claw 223 that separates the paper P sent out by the paper feed roller 58 into one sheet, and a stopper 225 that restricts the amount of downward rotation.

The rotating shaft 67 to which the paper feed roller 58 is attached has sponge rollers 227L and 227R on both sides of the paper feed roller 58.
is installed.

The manual feed guide 71 supported by the support shafts 73 and 75 has arms 229L12 on both lower sides that engage with the support shaft 75.
29R, and a paper discharge frame 233 is attached to the upper part via a pair of support parts 231. Note that this paper ejection frame 233 constitutes a paper ejection stacker together with the recessed portion of the conveyance guide 134 and the manual feed guide 71.

The support part 231 has a slit 235 that engages with a notch provided in the upper part of the manual feed guide 71, and also has a stopper 237, and this stopper 237 and the manual feed guide 71
A leaf spring 239 is interposed between the support part 2 and the back surface of the upper part.
31 is fixed to a manual feed guide 71, and the manual feed guide 71 is held on a support shaft 73.

A plurality of paper discharge rollers 241 are provided on the rotating shaft 108 as shown in FIGS. 5 and 8.

Further, the conveyance guide 134 forms a manual feed port 243 between it and the manual feed guide 71, and is formed in an N-shape so as to support the rear end of the paper P discharged by the paper discharge roller 241. Further, a static eliminating brush 245 is attached to the front surface of the conveyance guide 134 as shown in FIG.

The paper ejection guide 141 guides the paper P ejected from the printing unit 3 toward the paper ejection roller 241 side.
It has support plates 246L and 246k as shown in the figure, and is rotatably supported by side plates 56L and 56R about shafts 143 and 189.

The printing device configured as described above operates as follows. - First, rotate the lever part 202A of the set lever 202 shown in FIG.
1 to move the paper feed stacker 54 away from the paper feed roller 58.

Then, the sheets P are stacked on this sheet feed stacker 54 with their leading ends abutting against the stopper portion 195B of the bottom plate 195. At this time, the right stacker 54R is moved according to the width of the paper P.

Next, turn the platen knob 15L by hand while looking through the confirmation window provided on the side plate 56L, and when the color indicating the home position is visible, turn the platen knob 15L and set it to the home position.

Then, the lever portion 202A is rotated clockwise as shown by the solid line in FIG. 6 to remove the cam portion 202B from the pin 211. As a result, the return force of the spring 215 causes the paper feed stacker 5 to
4 is urged upward, and the paper P is pressed against the paper feed roller 58.

In this state, when a print command is issued, the helad carriage 27 shown in FIG. 4 moves from the left end home position to the center side and waits for paper to be supplied.

Further, the motor 23 in FIG. 1 is driven to rotate as shown in FIG. 11, and the platen shaft 13 rotates clockwise in FIGS. 9 and 10. For this reason, gear 17.107.109.1
Gear 119 rotates to the left via gears 11, 113, and 115. At this time, the ratchet pawl 123 is in contact with the inner circumferential surface of the cam 127, so it is not coupled to the ratchet 131. Therefore, the gear 129 does not rotate and the drive is not transmitted to the rotating shaft 67, so the paper feed roller 58 does not rotate.

As the gear 119 rotates, the ratchet pawl 123 engages the cam 1.
When it comes off from 27, it engages with ratchet 131. Therefore, the driving force of the gear 119 is transmitted to the gear 129, and the paper feeding roller 58 and the sponge rollers 227L and 227R rotate as shown in FIG. Rollers 227L, 22
7R, feed the paper P by the paper feed roller 58.
is pushed out.

At this time, both front ends of the paper P are caught by the separation claws 223 and 223 and begin to bend. Then sponge roller 2
27L and 227R are deformed by the force caused by the bending of the paper. When the deflection of the paper exceeds the elastic limit, both front ends of the paper P bounce and are separated into one sheet, which passes between the guide section 195C and the manual feed guide 71 and is fed between the platen 19 and the pressure roller 33. .

After the motor 23 starts rotating, the rotation of the motor 23 is stopped when it has rotated a predetermined amount M1 as shown in FIG. 11, that is, when the platen 19 and the pressure roller 33 have gripped the paper as shown in FIG. .

Then, the motor 23 is reversely rotated by a predetermined amount M2. As a result, the platen 19 rotates in reverse and discharges the paper P.

Incidentally, when the platen shaft 13 is reversed, the gear 119 also rotates in the opposite direction, but since the ratchet 131 idles relative to the ratchet pawl 123, the drive is not transmitted to the gear 129, and the paper feed roller 58 and sponge rollers 227L, 2
27R stops.

As a result, the paper P is bent between the platen 19 and the paper feed roller 58, and due to the stiffness of the paper P, the leading edge of the paper is bent to the platen 19.
and the pressure roller 33.

Then, when the platen 19 rotates normally again, the paper P is gripped between the platen 19 and the pressure roller 33, and the paper P is backed up and fed by the paper feed roller 58 at the rear.

When the gear 119 rotates further and the ratchet pawl 123 comes into contact with the inner peripheral surface of the cam 127, the ratchet pawl 1
23 is removed from the ratchet 131, the drive is no longer transmitted to the gear 129.

However, the paper P is connected to the platen 19 and the pressure roller 33.
．． 35, so the platen 19
The paper P is pulled by the rotation. Therefore, the paper feed roller 58 and the sponge rollers 227L and 227R rotate following the paper P.

When the motor 23 has rotated a predetermined amount M33, 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 on the center side, is returned to its home position on the left side by the movement of the carriage 27. Start printing. - The motor 23 rotates one line each time printing for each line is completed.

The printed paper P is guided along the paper discharge guide 141 and is discharged by the paper discharge roller 241. The leading edge of the ejected paper is in contact with the manual feed guide 71 and the paper ejection frame 233, and the trailing end is in contact with the transport guide 133.
It is supported in the recess of.

In the case of continuous paper feeding, the above operation is repeated, and the paper P is sent out in a constant cycle regardless of the length.

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

(1) After the paper sent out by the paper feed roller 58 is gripped between the platen 19 and the pressure roller 33, the paper is moved backward to form a sag and register, so that the paper is not gripped. At this time, the gap between the platen 19 and the pressure roller 33 rotating in the conveyance direction is
Since the paper is fed into the machine, the paper is smoothly gripped and the leading edge of the paper is not easily bent.

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) Since the registered paper is sent out by the paper feed roller 58, the platen 19 and the pressure roller 33
Since the platen 19, pressure roller 33, and the leading edge of the paper can be easily gripped between the platen 19 and the pressure roller 33, the discrepancy between the rotation of the motor 23 and the timing of gripping is reduced, and the paper is fed to the printing position. Can be fed smoothly and accurately.

(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 roller 33.

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, the platen rotates and the paper feed roller 58
1 rotates the motor 23 by a predetermined amount M2 after feeding the paper by a predetermined amount M1, thereby discharging the paper held between the pressure roller 33 and the platen 19.
A sensor may be provided at the tip of the pressure roller 33, and when the sensor detects the leading edge of the paper, the platen 19 may be reversed.

(3) As shown in FIG. 13, two or more pressure rollers 303, 30
5.307 may be pressed against the platen 309.

In this case, the paper may be held by the pressure roller 305i and then retreated to be ejected, or the paper may be held by the pressure roller 307 and then ejected.

(4) In the above embodiment, the platen 19 is driven and the pressure rollers 33, 35 are driven, or as shown in FIG. 13, the pressure rollers 303, 305, 307 may be driven and the platen 309 is driven.

Also, the platen 309 and pressure rollers 303 and 305
．． 307 may be driven together.

(5) This invention is based on the platen 311 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 313 is fed to a printing position by rollers 315, 317, 319, and 321.

(6) This invention provides a guide 323 as shown in FIG.
The paper guided by 325 is transferred to rollers 327 and 329.
．． 331.333 can also be applied to a printing device that supplies the printing position to the platen 335.

〔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 a printing device that performs printing work by feeding the sheet to a printing position, the sheet fed by the feeding means is held between the first conveying means and the second conveying means, and then The sheet is once retracted and discharged, and then the sheet is sent out by the feeding means, and then the sheet is held between the first conveying means and the second conveying means (by being held at the printing position). To provide a sheet cueing method for a printing device that prevents the leading edge of the paper from breaking during registration, allows the leading edge of the paper to be reliably registered, and allows the paper to be smoothly fed to the printing position. I can do it.

[Brief explanation of drawings]

Figures 1 to 4 are diagrams showing the configuration of the printing unit.
FIG. 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 10 are diagrams showing the configuration of the paper feed unit, where Figure 5 is a vertical sectional view showing the overall configuration of the paper feed unit, Figure 6 is a left side view of the area around the paper feed stacker, and Figure 7 is a diagram showing the structure of the paper feed unit. 8 is a right side view of the vicinity of the paper feed stacker, FIG. 8 is a partially cutaway plan view of the paper feed unit, and FIGS. 9 and 10 are diagrams showing the structure of the drive 1 delivery mechanism. FIG. 11 is a timing chart for explaining the operation.
FIG. 12 is an explanatory diagram of the operation. FIGS. 13 to 15 are diagrams showing modifications of the present invention. 3-----・Printing unit 19-・Platen 29・
...Print head 33.35...Fist press roller 101-...Paper feed unit 58...Paper feed roller 241-...Paper ejection roller dirt + diagram 13 Figure 30. 5″ j) 1/10 7.5″ times

Claims (5)

[Claims] (1) The stacked sheets are sent out one by one by a feeding means, and the sent out sheets are held between a first conveying means and a second conveying means that are pressed together and sent to a printing position, In a printing device that performs a printing operation, the sheet sent out by the feeding means is held between the first conveying means and the second conveying means, and then the sheet is once retreated and discharged. , and then the sheet is sent out again by the feeding means, and then held between the first conveying means and the second conveying means and sent to the printing position. How to cue. (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.