JPH08192546A - Inkjet printer - Google Patents

Abstract

PURPOSE: To provide a printer for which the technical problem in paper-carrying quality is eliminated by a method wherein a mechanism by which a printing head moves in two directions, in the paper discharging direction of a printing paper, is provided, and a mechanism which delivers/discharges the printing paper after completing a printing without performing the feeding/delivering motion of the printing paper, under a state wherein the printing paper is being set at a specified position, is provided. CONSTITUTION: For a printing head 1, a line head is adopted, and a paper cassette 2 is equipped with a hopper 7 wherein a cork 6 is arranged in the length direction of a printing paper 3, at both ends of the hopper 7, a luminar 9 at a discharging port part for the printing paper 3, and a spring 8 to support the hopper. By installing the paper cassette 2 in a printer, under a state wherein the printing paper is set, the printing paper 3 is brought into contact with a paper feeding belt 5 with teeth on one side, which is engaged with a paper feeding pulley 4 with teeth of a paper discharging mechanism, for the constitution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer which is a printing device for computers, office automation equipment and the like.

[0002]

2. Description of the Related Art A sectional view of a basic paper feeding mechanism according to the prior art is shown in FIG.

In FIG. 5, 14 is a print head, and 1 is a print head.
5 is a paper ejection star wheel (sawtooth roller made of metal or plastic material), 16 is printing paper, 17 is a paper ejection roller,
Reference numeral 18 is a transmission roller, 19 is a paper feed roller, 20 is a paper feed roller, 21 is a gate roller, and 22 is a paper feed auxiliary roller.

A conventional printer generally has a printing mechanism, which is provided in an outer case made of a plastic material.
An operation panel, an electronic circuit board for driving and control, a power supply circuit board, and an interface circuit board were housed.
Normally, the data transferred from the computer is transferred via the print head mounted on the printing mechanism.
A method of serially printing each character on a printing paper line by line was adopted. The printing mechanism can be roughly classified into a carriage on which a print head is mounted, that is, a carriage mechanism and a printing paper feeding mechanism, that is, a paper feeding mechanism. It can be said that the main problems facing conventional printers in the prior art are carriage position control in the printing direction and paper feed control from paper feed to paper feed / discharge / discharge. Among these, as for the paper feeding mechanism, as shown in FIG.
A method of completing printing along with a series of discharging operations has been adopted.

[0005]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is to eliminate the technical problem of paper conveyance quality from paper feeding to paper feeding, paper discharging and discharging.

When the paper transport quality is listed for each step,
There are the following issues. Paper feed accuracy: Print position accuracy, skew accuracy, paper feed failure, double feed, paper jam, etc. Paper feed accuracy: Single and cumulative pitch accuracy, skew accuracy, paper jam, etc. Paper ejection accuracy: Single and cumulative pitch accuracy, skew accuracy, paper jam, etc. Discharge accuracy: skew accuracy, paper jam, etc.

[0007]

SUMMARY OF THE INVENTION The present invention has a mechanism in which a print head moves in both directions in the discharge direction of print paper, and the print paper is set at a predetermined position. The solution is to have a mechanism for ejecting / discharging the printing paper after the printing is completed without feeding / feeding the printing paper.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 is a perspective view showing a first embodiment of a printer according to the present invention, FIG. 2 is a sectional view of a sheet discharging / discharging mechanism in the first embodiment, and FIG. 3 is a sectional view of a sheet feeding mechanism in the first embodiment. FIG. 4 is a sectional view of a sheet discharging / discharging mechanism in Embodiment 2 of the printer according to the present invention, and FIG. 5 is a sectional view of a sheet feeding mechanism according to the prior art.

[Embodiment 1] In FIG. 1, 1 is a print head, 2 is a paper cassette, 3 is a printing paper, 4 is a paper feed pulley with teeth, 5 is a paper feed belt with one side tooth, 6 is a cork, and 7 is a paper feed belt.
Is a hopper, 8 is a spring, 9 is a lumirror (a thin plate of a plastic material), 10 is a stacker, and 11 is a discharge roller.

Referring to FIG. 1, first, the method of setting the printing paper 3 in the paper cassette 2 is as follows. The printing paper 3 of is set.
The paper cassette 2 in this state is set at a predetermined position on the printer body. In this initial state, the spring force of the spring 8 is designed and adjusted so that the printing paper 3 contacts the one-side toothed paper feed belt 5. Further, by attaching the stacker 10 to which the discharge roller 11 is attached at a predetermined position of the paper cassette 2 afterwards, the printer of the present invention is ready for use. Print head 1
Employs a line head to print one line at a time and perform bidirectional scanning only in the paper discharge direction. Therefore, if the printer is provided with a buffer memory for one page, the print head 1
It is possible to efficiently print from the last line of the next page from the reverse direction without moving the to the initial position. Unlike traditional serial printheads, printheads,
That is, since the carriage position control is limited to the scanning direction of the print head 1, the motor control software can be simplified.

In this way, when printing of one page is completed, the printer of the present invention shifts to the discharging / discharging operation of the printing paper 3. As shown in FIG. 1, the printer of the present invention has a toothed paper feed pulley 4 and a toothed paper feed belt 5 on one side at both ends of the printing paper.
Have. In FIG. 3, when the printing paper 3 is discharged / discharged, one side of the outer surface is flat and the other side has a toothed shape. The toothed paper feeding belt 5 is a toothed paper feeding pulley. The printing paper 3 starts to move toward the front by 4 and the printing paper 3 is discharged by driving one page as it is. The inner surface of the one-sided toothed paper feed belt 5 has a tooth shape that meshes with the teeth of the toothed paper feed pulley 4, and the pulley and the belt perform a reliable interlocking operation without slipping. The tooth pattern of the one-sided toothed paper feed belt 5 has a half-moon shape so that the frictional force with the printing paper 3 becomes large. The paper feed is executed by making the most of this characteristic tooth profile. As a functional component for ejecting and ejecting the printing paper of the first page, a cork 6 that utilizes frictional force with the printing paper 3 is further added.
A lumirror 9 is installed on the front side of the paper cassette 2, that is, on the side of the print paper 3 in the setting direction and the side of the print paper 3 to be discharged and discharged in order to prevent double feeding of the print paper 3. When the printing paper 3 starts to be discharged or discharged, the printing paper 3 is moved on the driven type discharge roller and received by the stacker 10 in order to operate smoothly so as not to be affected by paper wrinkles due to ink absorption of the printing paper 3.

Next, the sequence of the second page of the printing paper 3 will be described. Regarding the printing, as described above, the position of the print head 1 may be either the initial position or the printing completed position. When one page of the printing paper 3 is discharged / discharged, the state of the belt 5 with one tooth is
There is a toothed belt on the upper side of the toothed pulley and a flat belt on the lower side. If the normal rotation is continued in this state, the second page is fed and the sheet is ejected or ejected before printing. In order to avoid this adverse effect, it is necessary that the toothed belt is always positioned on the printing paper 3 before printing. Therefore, as soon as the normal rotation drive is completed, the reverse rotation drive is executed this time, and the toothed paper feed belt 5 is returned to the initial position to solve the problem. This method has an important meaning in this mechanism because it can correct the misalignment of the second sheet during normal rotation during reverse rotation. It is considered that the printer of the present invention can achieve high throughput by driving such a paper feeding mechanism at high speed. The sequence of the third page of the printing paper 3 returns to the initial stage and the same operation as the first page is executed. That is, the odd number of sheets of printing paper becomes the same as the initial state.

[Embodiment 2] FIG. 4 is a cross-sectional view of the paper ejection / ejection mechanism of the second embodiment. Reference numeral 3 is a printing paper, 12 is a paper feed roller with a driving tooth (a toothed roller made of metal or plastic material), and 13 is a low friction driven roller. Other configurations are similar to those of the first embodiment.

First, the method of setting the printing paper 3 in the paper cassette 2 is the same as that in the first embodiment. After pushing the hoppers 7 with the springs 8 installed at the four positions of the paper cassette 2 by hand, a certain amount is set. The printing paper 3 of is set. The paper cassette 3 in this state is set in the mounting portion of the printer body. In this initial state, the spring force of the spring 8 is designed and adjusted so that the printing paper 3 comes into contact with the driving toothed paper feed roller 12 and the low friction driven roller 13.
Further, by attaching the stacker 10 to which the discharge roller 11 is attached at a predetermined position of the paper cassette 2 afterwards, the printer of the present invention is ready for use. The print head 1 employs a line head to print one line at a time and perform bidirectional scanning only in the paper feed direction. Therefore, one for the printer
If a buffer memory for pages is provided, it is possible to efficiently print from the last line of the next page in the reverse direction without moving the print head 1 to the initial position after printing one page. Unlike the conventional serial printhead, since the position control of the printhead, that is, the carriage is limited to the scanning direction of the printhead 1, the motor control software can be simplified.

In this way, when printing of one page is completed, the printer of the present invention shifts to the paper discharge / discharge operation of the print paper 3. As shown in FIG. 4, the printer of the present invention has a paper feed roller 12 with driving teeth and a low friction driven roller 1 at both ends of the printing paper.
3 In FIG. 4, when the printing paper 3 is discharged / discharged, the drive toothed paper feed roller 12 bites the printing paper 3 of the first page and starts moving in the front discharging direction. The printing paper 3 is discharged by driving by the minute. The main function of the low-friction driven roller 13 is a low friction force so that the paper-feed roller 12 with drive teeth is not loaded, and the function of pressing the printing paper 3 is great.

Thereafter, the paper discharge sequence for the second and subsequent pages of the printing paper 3 is the same as that for the first paper. Therefore, the paper discharge / discharge mechanism of the present invention is considered to be simple.

Regarding the printing, as described in the first embodiment, the position of the print head 1 may be either the initial position or the printing completed position. By bidirectionally scanning the print head 1, efficient and high throughput can be expected.

[0018]

As described above, according to the present invention,
An object of the present invention is to provide a printer that eliminates the technical problem of paper conveyance quality caused by feeding a printing paper.

[Brief description of drawings]

FIG. 1 is a perspective view of a first embodiment of a printer to which the present invention is applied.

FIG. 2 is a cross-sectional view of the main component layout in the printer embodiment 1 to which the present invention is applied.

FIG. 3 is a cross-sectional view of a paper feeding mechanism according to the first embodiment of the printer to which the present invention is applied.

FIG. 4 is a sectional view of a paper feeding mechanism in a printer embodiment 2 to which the invention is applied.

FIG. 5 is a sectional view of a paper feeding mechanism of a printer according to the related art.

[Explanation of symbols]

 1 Print Head 2 Paper Cassette 3 Printing Paper 4 Toothed Paper Feeding Pulley 5 Toothed Paper Feeding Belt 6 Cork 7 Hopper 8 Spring 9 Lumirror 10 Stacker 11 Discharging Roller 12 Drive Toothed Paper Feeding Roller 13 Low Friction Driven Roller 14 Printing Head 15 Paper discharging star wheel 16 Printing paper 17 Paper discharging roller 18 Transmission roller 19 Paper feeding roller 20 Paper feeding roller 21 Gate roller 22 Paper feeding auxiliary roller

Claims (6)

[Claims] 1. A mechanism for ejecting and ejecting the printing paper after the printing is completed without feeding or feeding the printing paper with the printing paper set in a predetermined position. An inkjet printer characterized in that 2. The ink jet printer according to claim 1, further comprising a print paper discharge / discharge mechanism at both ends of the print paper. 3. The inkjet printer according to claim 2, further comprising a mechanism for discharging and discharging a printing paper by driving a belt. 4. The ink jet printer according to claim 2, further comprising a roller-driving mechanism for discharging and ejecting printing paper. 5. The inkjet printer according to claim 3, further comprising a mechanism for discharging and discharging a print sheet by driving a toothed belt. 6. The ink jet printer according to claim 4, further comprising a printing paper discharging / discharging mechanism driven by a saw-tooth roller.