JPH02116574A - Inkjet printer paper feeding device - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field 1] The present invention relates to a paper feeding device for an inkjet printer using continuous paper.

] Conventional technology 1 Conventionally, in printers that feed continuous paper using a push tractor system, the tractor is reversed after printing, and
The structure is such that continuous paper is ejected and retracted outside the paper path.

1. Problems and Objectives to be Solved by the Invention 1. However, in an inkjet printer, if the ejecting and retracting operation is performed before the ink printed on the continuous paper dries, the undried ink will be removed between the paper guide plate and the continuous paper. There was a problem in that the printed continuous paper was smeared due to rubbing against the printed paper.

Therefore, in order to solve these conventional problems, the present invention has the following features:
While maintaining the maximum operability of paper that the push tractor method has, continuous paper can be ejected and retracted without causing printing stains due to undried ink at the paper guide plate and the elastic contact part of continuous paper (A). The purpose is to provide a paper feeding device that is possible.

[Means for Solving the Problems 1] In order to solve the above problems, the paper feeding device of the inkjet printer according to the present invention has the following features in the vicinity of the print head:
a paper path structure having a surface parallel to the printhead scanning direction;
a paper guide plate whose tip end is in elastic contact with the paper path structure;
In an inkjet printer, the inkjet printer is equipped with a means capable of cutting the paper across its entire width downstream from the printing position in the paper feeding direction, and a push tractor positioned upstream of the paper path structure and transporting the continuous paper. A control unit that includes a means capable of detecting the presence or absence of paper in the paper path on the side, and that retreats the continuous paper to a retreat position after printing has been completed and separation of the printed portion of the continuous paper is detected by the paper presence/absence detection means. It is characterized by having the following.

[Operation 1] In the paper feeding device of the inkjet printer configured as described above, the printed section of continuous paper is sent to the paper cutting position, where the continuous paper printing cleaning section is cut off, and then the continuous paper is cut off. When a retreat command is given, the control unit retreats the continuous paper to a prescribed position where the leading edge of the continuous paper after cutting passes through the paper presence/absence detection position, and - once at this position,
After the paper presence/absence detecting means detects the absence of paper and confirms that the printed portion of the continuous paper has been separated, the continuous paper is then retreated to the retreat position. In other words, when ejecting and retracting continuous paper, the printed part of the continuous paper must be separated, and therefore, the undried ink is rubbed between the paper guide plate and the printed part of the continuous paper. , it is possible to prevent the printed continuous paper from being stained.

[Embodiment 1] The details of the present invention will be explained below based on the illustrated embodiment.

FIG. 1 shows an embodiment of the present invention.

Reference numeral 1 in the figure is a platen, and a push tractor 2 for feeding continuous paper is disposed upstream of the platen 1 in the paper feeding direction (arrow A in the figure). The paper guide plate 3 is supported in elastic contact with the platen 1. A paper guide (lower) 4 is arranged below the platen 1, and the paper guide plate 3 and the paper guide (lower) 4 guide continuous paper fed by the push tractor 2 to a printing position. A reflective photosensor 5 that detects the presence or absence of paper in the paper path and its reference position (second reference position) is disposed downstream of the printing position, and a paper cutter 6 is further disposed downstream of the reflection type photosensor 5. In the figure, reference numeral 7 indicates a paper detection sensor that detects the entry of the paper into the paper path and its reference position (first reference position), reference numeral 8 indicates the print head, and reference numeral 9 indicates the paper.

These platen 1 and push tractor 2 are connected to a pulse motor 10 via a transmission mechanism. This pulse motor 10 is driven by a motor drive circuit 18 that receives signals from a control section r1120 (described later) consisting of a microcomputer and a print signal from a host device.

Figure 2 was mentioned above! lJg! When the leading edge of the paper reaches a certain position, for example, the detection position of the paper detection sensor 7 or photosensor 5, it adds or subtracts the drive pulses to the pulse motor lO to detect the paper. The paper feed amount detection means 21 detects the feed amount, the paper detection sensor 7 detects the time when the leading edge of the continuous paper passes the first reference position, the first reference position detection means 22 detects the time when the leading edge of the continuous paper passes the first reference position, and the photo sensor 5 A second reference position detection means 23 detects when the leading edge of the paper passes the second reference position, a signal from the evacuation command switch 19, and a first reference position detection means 22.
The separation operation command means 24 causes the continuous paper printing cleansing section to feed the paper by the specified distance fL1 to the separation position in response to a signal from the evacuation command switch 19, the first reference position detection means 22, and the second reference position detection means. After a signal from the means 23 causes a reversal by a specified amount L2 from the separation position to the second reference position, and after confirming that there is no paper at the second reference position, the reversal is then performed by a specified amount L3. ,
It is comprised of a retracting operation command means 25 for setting the leading end of the continuous paper to the retracting position.

Therefore, the details of the present invention will be explained in detail below based on the illustrated embodiments. After printing, a signal from the evacuation command switch 19 on the panel causes the separation operation command means 24 to be activated.
outputs a drive signal corresponding to the paper feed amount L1. In response to this signal, the motor drive circuit 10 rotates the pulse motor in the forward direction to feed the continuous paper by a prescribed amount L1 to the separation position.

(Fig. 3-■) In this state, after cutting off the printed portion of the continuous paper using the paper tensioner 6, when another signal is sent from the evacuation command switch 19, the evacuation operation command means 25 performs the prescribed operation. A reverse rotation drive signal corresponding to the paper feed amount L2 is output. As a result, the motor drive circuit 18 reverses the pulse motor 10 to move the continuous sheet of paper after the printed portion has been separated to a second reference position where the leading edge thereof passes the reflective photosensor 5.

When the leading edge of the continuous paper passes the photosensor irradiation section, the light that was previously reflected by the paper (white) and incident on the photosensor light receiving element will now hit the platen 1, which is less likely to reflect light, and the light receiving element will no longer reflect the light. Unable to detect light. When the second reference position detection means 23 detects that the printed portion has been separated, the evacuation operation command means 25 sends a reverse drive signal corresponding to the paper feed amount L3 from the second reference position to the continuous paper evacuation position. output and set the continuous paper in the evacuation position. (Fig. 3 - ■■) If the printed portion of continuous paper is not separated and a reverse drive signal is output from the evacuation command means 25 in response to the signal from the evacuation command switch 19, the continuous paper will continue for L2. When the paper is in a backward state, the leading edge of the continuous paper cannot pass through the second reference position. Therefore, the second reference position detection means 23 determines that the printed portion of the continuous paper has not been separated, and the evacuation operation command means 25 corrects the pulse motor with a forward rotation drive signal corresponding to the feed amount L2. Then, the continuous paper is fed out again to the cutting position, and the user is prompted to cut off the printed portion.

In other words, when the continuous paper is retreated to the retracted position, the printed portion is always separated, so that the printed surface is not smudged by undry ink.

FIG. 4 is a flowchart showing the operation of the apparatus according to the embodiment described above. The explanation will be given below.

After recognizing that the evacuation command switch 19 has been turned on, the separation operation command means 24 recognizes whether there is paper or no paper at the first reference position, and then whether there is paper or no paper at the second reference position. When the presence of paper is recognized at both reference positions, the paper is fed by a specified amount Ll and the continuous paper is cut.
Pull it out to the release position.

If it is recognized that there is no paper at the first reference position, the operation ends at that point, and if it is recognized that there is no paper at the second reference position, the evacuation operation command means 25 moves the continuous paper by a specified amount L3. Move it backwards and set it to the sheltered position to complete the operation.

Next, when the evacuation command means 25 recognizes that the evacuation command switch 19 has been turned on again, it moves the continuous paper back by a prescribed amount L2, and then recognizes whether there is paper or there is no paper at the second reference position. . If it is recognized that there is no paper at this point, the evacuation operation commanding means 25 moves the continuous paper back by a specified distance @L3, sets it at the evacuation position, and ends the operation. When the presence of paper is recognized, the continuous paper is fed out by L2 and set at the separation position again.

FIGS. 5 and 6 show another embodiment in which a combination of a detection lever and a photo interrupter is used as the means for detecting the presence or absence of paper after printing.

The detection lever 11 is rotatably supported by a lever shaft 12, and the tip of the detection lever 11 is pushed by a spring 13 against the back surface of the continuous paper in the direction of arrow C in the drawing on the downstream side of the printing section on the circumference of the platen. The platen 1 is provided with a groove in which the detection lever 11 can be stored and which does not interfere with the rotational movement of the detection lever 11. Further, the flag portion 14 of the paper detection lever 11 is shaped to shield the photointerrupter from light when the tip of the paper detection lever 11 protrudes from the circumferential surface of the platen 1 (FIG. 6-II). .

The shuriken-shaped paper presser 15 is located near the position where the detection lever 11 detects the presence or absence of paper and upstream of the paper force vine 6, and prevents the continuous paper with clear printing from lifting off the circumference of the platen. I'm here. Further, the paper presser 15 is located at a location where it does not directly push the detection lever 11 in the paper width direction. Reference numeral 16 in the figure is a photo interrupter, which is fixed to a paper guide plate (upper) 17 that guides the cut sheet to the platen.

When using the paper presence/absence detection means configured in this way,
When the continuous paper is fed to the separation position, the continuous paper is forced along the circumference of the platen by the paper presser 15, and the back side of the continuous paper presses down the tip of the paper detection lever 11 to the circumference of the platen, so that the flag section 14 is activated by the photoinput. Open the light receiving part of the club.

(Fig. 6-■) After cutting off the continuous paper in this state, when the evacuation command switch 19 retreats to a position where the leading edge of the continuous paper passes the detection position, the detection lever 11 is activated by the spring force. returns to a position protruding from the circumferential surface of the platen, shielding the light receiving section of the photointerrupter 17 from light. (6th
FIG. 11) By opening and closing the photo-interrupter light-receiving section described above, it becomes possible to detect separation of the printed portion of continuous paper, and it is possible to obtain the same effect as in the embodiment described above.

If you use this kind of paper presence/absence detection means that combines a detection lever and a photo ink brush, it will be possible to detect the platen surface,
Less susceptible to changes in the optical state of the surface of continuous paper ↓
It is possible to detect continuous paper separation with high reliability.

In the embodiments described above, the ejection and retraction operation for continuous paper was described, but it is possible to perform ejection and retraction operations for cut paper and continuous paper.
In addition, when switching from continuous paper to cut paper in an inkjet printer having automatic paper type selection means, by using the above embodiment, automatic paper type selection can be performed without undried ink staining the printing surface. You can do this.

[Effect of the Invention 1] As explained above, according to the present invention, the means capable of detecting the presence or absence of paper in the paper path on the downstream side of the printing position can be eliminated, and after printing is completed, the means for detecting the presence or absence of paper can detect We have installed a control unit that moves the continuous paper back to the evacuation position after detecting the separation of the printed section of the continuous paper, so that during the ejection and evacuation operation, the elastic contact between the paper guide plate and the continuous paper causes the printing surface to be damaged by undried ink. can be prevented from becoming dirty.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a device showing an embodiment of the present invention, FIG. 2 is a block diagram showing an embodiment of a control device in the same device, FIG. 3 is an explanatory diagram showing the operation of the same device, and FIG. The figure is a flowchart showing the operation of the same device. FIG. 5 is a schematic diagram showing another paper presence/absence detection means, and FIG. 6 is an operation diagram thereof. 1...Platen 2...Push tractor 3
...Paper guide board 4...Paper guide (bottom) 5...
Reflective photo sensor 6...Paper strength 7...Paper detection sensor 8...Print head 9...Yoi Mr.
10...Pulse motor 11...Detection lever
12...Detection lever shaft 13...Spring 14
...Flag 15...Paper presser 16...Photo ink label 17...Paper guide (top) Applicant: Seiko Epson Co., Ltd. Representative Patent Attorney Kisanbe Meiki and 1 other person

Claims (1)

[Claims] In the vicinity of the print head, there is a paper path structure having a surface parallel to the print head scanning direction, a paper guide plate whose tip is in elastic contact with the paper path structure, and a paper path structure that moves the paper over its entire width downstream from the print position in the paper feed direction. In an inkjet printer comprising a means capable of cross-cutting and a push tractor positioned upstream of the paper path structure and transporting continuous paper, means capable of detecting the presence or absence of paper in the paper path downstream from the printing position. and a control unit for retracting the continuous paper to a retreat position after the paper presence/absence detecting means detects separation of the printed portion of the continuous paper after printing is completed. Device.