JPH02204073A - Liquid jet printer - Google Patents

Abstract

PURPOSE:To enable the back feed and the employment of application software through a simple structure by providing a means interlocked with back feed of a body to be recorded to separate an energizing member from the surface of the body to be recorded. CONSTITUTION:Upon counter clockwise rotation of a feed roller 11 for the purpose of back feed, a one-way clutch 19 is coupled with the feed roller 11 and rotates integrally. In this process, an arm 17 separates an energizing member 2 from the surface of a body to be recorded thus producing a space with respect to the surface of the energizing member 2. Lower end face of the arm 17 contacts with a regulation pin 18 at a point of some rotary amount thus stopping the separating motion of the energizing member 2. If back feed has not finished at this time point, the feed roller 11 rotates counter clockwise but the one-way clutch 19 slips with respect to the feed roller 11 and only the feed roller 11 continues rotation. Since a space is formed between a body 15 to be recorded and the energizing member 2, print quality is maintained even if the recording liquid adhered onto the recording face has not yet fixed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a liquid jet recording device. The present invention relates to a liquid jet recording apparatus that performs recording by flying ink droplets onto a recording medium according to recording information, and is equipped with means for conveying and holding the recording medium.

[Conventional technology]

Recording devices such as printers and facsimiles can be classified into thermal types, wire dot types, liquid jet types, etc. depending on the recording method.

Among these, the liquid jet recording method (inkjet recording method) supplies ink to a recording head that has at least one fine orifice (or nozzle), and drives an energy generator provided in the orifice based on print data. The ink droplets are applied to the ink in the orifice to cause ink droplets to fly from the tip of the orifice, and these ink droplets are attached to a recording medium such as plain paper or a thin plastic plate to form a dot pattern. There is.

FIG. 8 shows a perspective view of a recording section of a conventional liquid jet recording apparatus, and FIG. 9 is a schematic cross-sectional view of the apparatus shown in FIG.

8 and 9, 1 is a liquid ejecting head, 2 is a recording medium (plain paper, thin plastic plate, etc.) placed on a platen 3.
3 is a platen, 4 is an ejection roller that conveys the recorded object, 5 is a pail roller that comes into contact with the ejection roller 4, 6 is a carriage on which the liquid ejecting layer 1 is mounted, 7 is a timing belt for reciprocating the gear ridge 6; 8 is a sliding shaft for slidably holding the carriage ridge 6; 9 is a motor for moving the feed roller 11;
10 is an ejection recovery device; 11 is a feed roller that supplies the recording medium to the platen 3; 12 is a pinch roller that presses the recording medium against the feed roller 11; 13 is a vapor pan disposed below the feed roller 11; Reference numeral 14 denotes a vapor guide for accommodating the discharged recording object, 15 the recording object, and 16 a motor serving as a drive source for moving the carriage 6.

In the above configuration, when recording is performed, the leading end of the recording medium 15 is inserted between the vapor guide 14 and the vapor pan 13, and the feed roller 11 is rotated to send it to the recording start position. In this state, a print command is output, ink droplets are ejected from the liquid ejecting head 1 to perform recording, and the motor 16 is driven to rotate the timing belt 7 and move the carriage 6. Every time recording for one line is completed, the feed roller 11 rotates and the recording medium 1 is moved by the line interval.
5 is sent to the river. At this time, the biasing member 2 restricts the movement of the recording object 15 so that the recording object 15 does not float off the platen 3.

Normally, the biasing member 2 is in contact with the surface of the recording medium 15.

When the printing is completed, the carriage 6 is returned to the home position, and the recording medium 15 is forward-fed while being inserted between the ejection roller 4 and the pail roller 5, and the vapor guide 1
4 Sent upwards.

Printing accuracy and print quality in a liquid jet recording device become better as the distance between the recording head and the recording medium becomes closer. Further, the more uniform the intervals are, the more uniform the printing results can be obtained. This interval is Q, 3 haze m ~ 2.5 u
However, in order to uniformly form it within a narrow space, advanced technology is required. For this reason, conventionally,
The biasing member is placed close to the printing position and is installed so that the recording medium does not lift up.

[Problem to be solved by the invention]

However, such a conventional liquid jet recording apparatus requires time for the recording liquid (ink) absorbed onto the recording medium to be fixed.

This time is not constant, but is limited by the time it takes for the recording liquid to evaporate, or it varies depending on the time until the recording liquid is absorbed into the recording medium by capillary action. Therefore, when a backfeed command is executed, when the unfixed part is fed between the platen and the biasing member +4, the unfixed ink is rubbed against the biasing member, causing bleeding and running, which deteriorates the print quality. cause This tendency becomes more pronounced as the humidity increases.

For this reason, backfeed commands have conventionally been dealt with by taking measures such as not executing the function corresponding to the command using firmware on the recording apparatus side, or by incorporating an alternative function. However, when doing this, the printing results differ when using conventional application software, and it takes a lot of effort to create the firmware that runs the recording device, making it inconvenient to use and inefficient. .

One means to solve this problem is to move the biasing member away from the printing position to provide a time margin for some backfeed. However, in this case, the vapor path becomes longer, and it is necessary to separately provide a means for uniformly pressing the recording object against the platen, which increases the size and complexity of the device, so it is difficult to avoid high prices. do not have.

An object of the present invention is to provide a liquid jet recording device that can solve the problems of the prior art, enable the adoption of backfeed and application software, and achieve faster, higher quality, and quieter recording. It is to be.

[Failure to solve the problem]

According to the present invention, the biasing member is moved away from the surface of the recording medium in conjunction with the backfeed of the recording medium, and
This is to achieve the above purpose.

The biasing member is separated only when backfeeding is performed before completion of fixing, so that unnecessary driving is not required.
It is preferable that the biasing member 2 is turned on and off when the feed is performed within a set time after recording.

Furthermore, the back feed 1
After completing spinning, it is desirable to return the biasing member to its normal position before starting the next recording.

[Function] By configuring as claimed in claim 1, the urging member is separated from the surface of the object to be recorded during backfeed, and a space is formed between the urging surface and the surface of the object to be recorded. ,
Unfixed recording liquid does not adhere to or rub against the biasing surface of the biasing member.

Therefore, there is no deterioration in print quality.

By configuring as in claim 2, the biasing member is separated only when the set time 1' has not elapsed since the recording was made. By setting the set time to a time sufficient for the recording liquid to complete fixing, the biasing member can be driven only when necessary.

Further, by configuring as claimed in claim 3, the biasing member returns to the normal position after the backfeed is completed, and is prepared for the next recording, so that the biasing member can perform its function for the first time. is set to

〔Example〕

Hereinafter, the present invention will be basically explained with reference to FIGS. 1 to 7.

FIG. 1 is a schematic side view showing an embodiment of a liquid jet recording apparatus according to the present invention. In this embodiment, the same reference numerals are used for the same parts as in the conventional device shown in FIG. 9, and therefore, redundant explanation will be omitted below.

In FIG. 1, I7 pushes the upper part of the biasing member 2 onto the recording medium 15.
A release arm 18 is fixed to a chassis or the like to restrict rotation of the arm 17, and 19 is a one-way clutch installed coaxially with the axis of the feed roller 11. Arm 17 is -i
The urging member 2 is attached to the upper part thereof, and the other end thereof is pivotally supported eccentrically on a part of the sea urchin roe 19 so as to be freely rotatable.

The one-way clutch I9 does not apply a load to the feed roller 11 when the feed roller II rotates clockwise, but acts as a load and rotates integrally with the feed roller 11 when the feed roller II rotates counterclockwise. The arm 17 is driven.

In the above configuration, the recording medium 15 is
When inserted onto the feed roller 1''1, it rotates in close contact with the feed roller 1''1 while being pressed by the pinch roller 12 as the feed roller 11 rotates in the direction of the force.At this time, the feed roller 1'' rotates. The arm 17 is not driven and remains stopped. Since the arm 17 is stopped, the A1 member 2 feeds the recording material 15 to the roller 11. It biases and prevents the surface of the paper from lifting up.

Next, when the feed port 11 rotates in the counterclockwise direction for backfeed, the one-way clutch 19 is coupled to the feed roller 11, and the two rotate as one. In this process, the arm 17 moves in the length direction according to the amount of rotation of the one-way clutch 19, moves the biasing member 2 away from the surface of the recording medium, and creates a space between the biasing member 2 and the surface of the biasing member 2. The lower end surface of the arm 17 reaches the regulating bin 1 at the rotation amount.
8 and this state is maintained, and the separating operation of the biasing member 2 is stopped. If the backfeed is not completed at this point, the feed roller 11 will further rotate counterclockwise, but since the one-way clutch 19 has a friction structure, it will slip against the feed roller 11, causing the feed roller 11 to rotate counterclockwise. The chisel continues to rotate.

By forming a space between the recording medium 15 and the biasing member 2, even if the recording liquid (ink) attached to the recording surface is not fixed, it will not be rubbed by the biasing member 2. The print quality is maintained.

FIG. 3 shows another embodiment of the present invention, which is characterized in that a plunger 20 is used in place of the one-way clutch 17. The plunger 20 is arranged so as to be able to apply a biasing force to the biasing member 2 in the opposite direction to the biasing force of the elastic body 27 for biasing the biasing member 2 toward the recording medium. Further, since the armature of the plunger 20 has a fixed movable range, the regulating bottle 1B is not necessary.

Normally, the plunger 20 is demagnetized, and the biasing member 2 is brought into contact with the recording medium 15 by the biasing force of the elastic body 27. During backfeed, the plunger 20 is excited, and the biasing member 2 is biased in the opposite direction to the feed roller 11, and is moved away from the normal position. As a result, the recording medium 15
Contact between the printing surface and the biasing member 2 can be avoided, and printing quality can be maintained. When the backfeed is finished,
The plunger 20 is demagnetized, and the biasing member 2 is pulled by the elastic body 27 and rotates to a position where it comes into contact with the recording medium 15 .

FIG. 4 shows a modification of the embodiment shown in FIG. 3, in which the feed roller 1
A detection gear 21 is attached to the side surface of the chassis 1, and a detection member 22 is fixedly installed facing the detection gear 21 upside down on the chassis.

In this configuration, when backfeed is performed, the rotation of the feed roller 11 at that time is detected from the movement of the detection gear 21. With this configuration, even if the feed roller 11 rotates in reverse due to external force and a hack feed is performed, the plunger 20 can be controlled from the detection of rotation.

In addition to the configuration example shown in FIG. 3, there are, for example, configurations shown in FIGS. 5, 6, and 7. In either case, the movement of the recording medium 15 can be detected with high accuracy. FIG. 5 shows a structure in which a rack 24 is provided at the base of the biasing member 2 so as to be movable on the chassis S, and a gear mechanism 23 is provided to drive the rack 24 back and forth in the longitudinal direction according to the rotation of the feed roller 11. This is what I did.

Further, in FIG. 6, a ratchet mechanism 25 is provided integrally and coaxially with the feed roller 11, and an arm 26 having a pin that can be locked to the ratchet mechanism 25 is provided on the urging member 2. .

When the feed roller 11 rotates clockwise, the ratchet device 1125 and the arm 26 are not engaged, and no pressing force is applied to the biasing member 2. On the other hand, when the feed roller 11 rotates counterclockwise, the teeth of the ratchet mechanism 25 engage the arm 26, and the biasing member 2 is moved away from the surface of the feed roller 11 against the biasing force of the elastic body 27. Move to. The amount of movement of the biasing member 2 in this case is equal to the backfeed amount or the like.

Furthermore, FIG. 7 shows the housing 28 of the one-way clutch.
A cam-shaped part 29 is provided on the cam-shaped part 29 so that the cam-shaped part 29 rotates counterclockwise together with the feed roller 11 during backfeeding, and can press the biasing member 2. When the cam-shaped portion 29 comes into contact with the regulating bin I8, it is fixed at that position, and when the feed roller 11 rotates clockwise, it is returned to its normal position, and the A-1 force member 2 can also be biased. become.

Note that the movement of the biasing member 2 is necessary because the recording liquid on the surface of the recording medium 2 is not yet dried, and when the backfeed is performed after the recording liquid is fixed (after drying). There is no need to move the biasing member 2, therefore,
For hack feeds that occur after a certain period of time (longer than the time it takes to complete fixing) after printing,
The sequence may be such that the biasing member 2 is not activated.

Furthermore, since the fixing time is greatly affected by the surrounding environment, it is possible to detect these environmental conditions, determine the optimal fixing time, and disable the operation when the interval is longer than that, or to check whether fixing has occurred or not. It is possible to use a method such as providing a sensor for determining fixing and disabling the biasing member when the sensor determines fixing.

Also, while performing backfeed, the biasing member is moved in the same direction as the feeding direction of the recording medium, and even if the operation to prevent printing stains is performed, the recording medium will stop and the backfeed will be interrupted. It is also possible to adopt a configuration in which, when recording is completed and the recording is performed again, the biasing member returns to the initial setting position and biases the recording medium.

〔Effect of the invention〕

According to the present invention, configured as described above, the following effects can be achieved.

According to the liquid jet recording apparatus of the first aspect, since the driving means for moving the biasing member away from the surface of the recording medium in conjunction with the backfeed of the recording medium is provided, the backfeed can be prevented with a simple configuration. It is possible to use commonly used ablation software for the corners, and it is possible to obtain a liquid jet recording device that is high speed, high precision, high quality, and excellent in quietness.

According to the liquid jet recording device according to the second aspect, since the biasing member is separated when the backfeed is performed within a set time, the biasing member is not moved unnecessarily and consumption is reduced. can be prevented and the occurrence of failures etc. can be reduced.

According to the liquid jet recording device according to the third aspect, since the biasing member is returned to the normal position after the end of the backfeed and before the start of the next recording, even if recording is restarted, the biasing member is returned to the normal position at the same time. can function normally and will not interfere with recording.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view showing an embodiment of a liquid jet recording device according to the present invention, FIG. 2 is a schematic side view showing the configuration of the embodiment shown in FIG. 1 at the time of backfeed, and FIG. FIG. 4 is a schematic side view showing a modification of FIG. 3, and FIGS. 5, 6, and 7 are schematic side views showing other embodiments of the invention. FIG. 8 is a perspective view showing a conventional liquid jet recording device, and FIG. 9 is a schematic side view of the device shown in FIG. 1------Liquid ejecting head, 2----Biasing member, 3----Platen, 6-------Carriage, 11--Feeding Laura, 15--...
---Recorded object, 17--Release arm, 18-
...--11 Regulatory bottle, 19--Ja, 2 Material, 23 5---7. One-way clutch, 20-------Bran 1
−・−・−・・Detection gear, 22−・−・−・・−Detection unit・−・−Gear mechanism, 24−・・・・Rank, 2 lathe lift mechanism, 26・・−・・・・・Arm, 2
Elastic body.

Claims (3)

[Claims] (1) A recording device that records images and characters by ejecting and flying recording droplets from a nozzle of the head toward a recording object according to the recording information, and a biasing member that biases the recording object against the platen. What is claimed is: 1. A liquid jet recording apparatus comprising: a driving means for moving the biasing member away from the surface of the recording medium in conjunction with backfeed of the recording medium. (2) The liquid jet recording apparatus according to claim 1, wherein the biasing member is separated when the backfeed is performed within a set time. (3) The liquid jet recording apparatus according to claim 1, wherein the biasing member is returned to the normal position after the end of the backfeed and before the start of the next recording.