JP2002301847A - Recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a recording apparatus, capable of restraining lift up of the recording sheet rear end, and capable of executing a highly accurate printing operation to the recording sheet rear end in a vertically arranged recording head. SOLUTION: In a serial type recording apparatus comprising a conveying means (a conveying roller 1 and a pinch roller 2) for conveying a recording sheet S, a recording head 6 for recording an image on the conveyed recording sheet S, and a carriage 7 for holding the recording head 6, for recording by moving the carriage 7 in the vertical direction for scanning with respect to the recording sheet conveying direction, a recording operation is executed by scanning with the carriage 7, conveying the recording sheet S by a predetermined amount and repeating scanning by the carriage 7 in an ordinary recording operation, and scanning with the carriage 7 moved by a predetermined mount each time to the upstream side in the recording sheet conveying direction with the rear end of the recording sheet S held by the conveying means in a recording operation on the recording sheet S rear end part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a serial type recording apparatus, and more particularly to a recording apparatus in which a recording head has a recording section of a plurality of colors in a recording sheet conveying direction.

[0002]

2. Description of the Related Art A recording device having a function such as a printer, a copying machine, a facsimile, or a recording device used as an output device of a composite electronic device or a workstation including a computer or a word processor, etc., is based on image information. It is configured to record an image on a recording material (recording medium) such as a plastic thin plate. These recording apparatuses can be classified into an ink jet type, a wire dot type, a thermal type, a laser beam type, and the like according to a recording method.

In a serial type recording apparatus employing a serial scanning system in which a main scan is performed in a direction intersecting a conveying direction (sub-scanning direction) of a recording material, a recording means mounted on a carriage which moves along the recording material. The image is printed (main scanning), and after the printing of one line is completed, a predetermined amount of paper feed (pitch conveyance) is performed, and then the image of the next line is printed again on the stopped recording material ( By repeating the operation of (main scanning), recording of the entire recording material is performed.

Among the above recording apparatuses, an ink jet type recording apparatus (ink jet recording apparatus) performs recording by discharging ink from a recording means (recording head) onto a recording material. It is easy, can record high-definition images at high speed, can record on plain paper without special processing, has low running cost and is non-impact method, so there is little noise, and It has the advantage that it is easy to record a color image using multicolor inks.

A recording head for recording a color image using multicolor inks has a plurality of nozzle rows for printing different colors in the main scanning direction (horizontally arranged heads). Some of the rows have a portion that records different colors in the recording sheet conveyance direction (a vertically aligned head), and some have a combination of the two.

When recording is performed on a recording sheet by such a recording apparatus, the recording sheet S is usually fed onto a platen 5 by a conveying roller 1 and a pinch roller 2 as conveying means, as shown in FIG. After the recording is performed by the discharge roller 6, the paper is discharged by the discharge roller 3 and the discharge spur 4 of the discharge means.

The conveying force of the recording sheet S is higher in the conveying section than in the discharging section.
The peripheral speed is slightly faster than that. This is to prevent the recording sheet S from becoming loose in the printing section.

[0008]

However, as shown in FIG. 10, when the trailing end of the recording sheet S comes off the pinch roller 2, the trailing end of the sheet S moves away from the platen 5 due to the curl or folding of the recording sheet S. May rise.

When the trailing edge of the recording sheet S rises, not only the print quality deteriorates due to a change in the distance and angle between the recording head 6 and the recording sheet S, but also the rising recording sheet S and the recording head 6 come into contact with each other. This may cause the recording sheet S to be stained or the recording head 6 to be damaged.

[0010] In addition, since the paper discharge section is set to have a larger transport amount and a lower transport force than the transport section, when printing is performed while the recording sheet S is being transported only by the paper discharge section, recording is performed. Depending on the type of the sheet S and the use condition of the apparatus, the conveyance amount of the recording sheet S may vary and printing may be disturbed. In addition, printing irregularities may occur due to kicking of the recording sheet S which occurs at the moment when the trailing edge of the recording sheet S passes through the pinch roller 2.

On the other hand, if printing is not performed after the trailing edge of the recording sheet S is disengaged from the pinch roller 2, the margin of the trailing edge of the recording sheet S in a vertically aligned head becomes large, The printable area is reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and its object is to prevent the trailing edge of a recording sheet from being lifted, and to achieve high precision even in a vertically arranged recording head up to the trailing edge of the recording sheet. An object of the present invention is to provide a recording device capable of performing printing.

[0013]

In order to achieve the above-mentioned object, the invention according to claim 1 comprises a conveying means for conveying a sheet-like recording sheet, and an image recording apparatus for recording an image on the conveyed recording sheet. In a serial type recording apparatus that has a recording head and a carriage that holds the recording head, and performs recording by scanning the carriage in a direction perpendicular to the recording sheet transport direction, the carriage scans during normal recording. After recording, the recording sheet is conveyed by a predetermined amount and the carriage scans again, but when recording is performed on the rear end of the recording sheet, the rear end of the recording sheet is held by the conveying means, The recording is performed by moving the carriage by a predetermined amount in the upstream direction of the recording sheet conveyance direction and scanning the carriage.

According to a second aspect of the present invention, in the first aspect of the present invention, the recording head comprises a recording head having a plurality of recording colors in a recording sheet conveying direction.

[0015]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a side view of a printing unit of the printing apparatus according to the present invention, FIG. 2 is a front view of the printing unit, FIG. 3 is a cross-sectional plan view of a carriage, and FIG. 5 is a front view of the printing section when passing the trailing edge of the recording sheet, FIG. 6 is a cross-sectional plan view of the carriage when passing the trailing edge of the recording sheet, and FIG. 8 is a cross-sectional plan view of the carriage at the end of printing on the trailing edge of the recording sheet.

The recording sheet S is fed by a sheet feeding device (not shown), fed between the transport roller 1 and the pinch roller 2, and transported onto the platen 5 by the transport roller 1 and the pinch roller 2. Then, printing is performed on the recording sheet S by the recording head 6 held on the carriage 7 on the platen 5, and thereafter, the recording sheet S passes between the discharge roller 5 and discharge spur 6 serving as a discharge means. It is discharged outside the device.

The carriage 7 is guided by a guide shaft 8 and a guide rail 9, and the driving force from a carriage driving motor 10 is transmitted by a timing belt 11 to the carriage 7.
, The carriage 7 is driven. The guide shaft 8 is supported by left and right side plates 12 and 13, and pins 14 and 15 are attached to the side plates 12 and 13, respectively.

The carriage 7 includes a head support 71, a guide 72, a cam 73 and a spring 74. The head support 71 is urged toward the guide 72 by a spring 74. The step of the cam 73 is set to the same pitch as the transport amount of the recording sheet S performed during normal printing.

The leading and trailing ends of the recording sheet S are detected by a PE sensor 16 and a PE sensor lever 17.

Next, the operation for printing the rear end of the recording sheet S will be described.

If the trailing edge of the recording sheet S is detected by the PE sensor 16 and it is determined that printing is to be performed after the trailing edge of the recording sheet S has come off the pinch roller 2, the recording sheet S is conveyed first. Is stopped at the position shown in FIG. 4, and printing is performed up to that position.

Thereafter, the carriage 7 is moved to the position shown in FIG. When the cam 73 slides, the head support 71 moves by the step difference of the cam 73 to the guide 72 (see FIG. 6). After printing is performed in this state, the carriage 7 is again moved to the pin 14 side, and the cam 73 is slid to move the head support 71 to the upstream side in the transport direction of the recording sheet S again.
Printing is performed by moving the printhead stepwise. At this time, the moving amount of the carriage 7 is increased in accordance with the pushing amount of the cam 73 by the pin 14. When printing is performed to the end by repeating this, the carriage 7 is in the state shown in FIGS.
Then, this time, the carriage 7 is moved to the side plate 13 side,
The cam 73 is pushed by the pin 15 to return the position of the cam 73 to the initial position.

In the present embodiment, the carriage 7 is moved in the conveying direction of the recording sheet S using the cam 73. Instead, the motor 7 is used to move the carriage 7 using a rack and a pinion or a lead screw. The movement may be performed. In this case, the moving amount of the carriage 7 can be made variable.

[0025]

As is apparent from the above description, according to the present invention, a conveying means for conveying a sheet-like recording sheet and a recording head for recording an image on the conveyed recording sheet are provided. In a serial type recording apparatus having a carriage for holding the recording head and performing recording by scanning the carriage in a direction perpendicular to the recording sheet conveyance direction, during normal recording, the carriage scans and records. Thereafter, the carriage repeats scanning the carriage again after transporting the recording sheet by a predetermined amount.When recording is performed on the trailing edge of the recording sheet, the trailing edge of the recording sheet is held by the transporting means, and the carriage is printed. Since the recording is performed by moving and scanning by a predetermined amount in the upstream direction of the sheet conveyance direction, the floating of the trailing edge of the recording sheet can be suppressed, Effect that can also be of printing precision to the recording sheet rear end in the arrangement of the recording head.

[Brief description of the drawings]

FIG. 1 is a side view of a printing unit of a recording apparatus according to the present invention.

FIG. 2 is a front view of a printing unit of the recording apparatus according to the present invention.

FIG. 3 is a plan sectional view of a carriage of the recording apparatus according to the present invention.

FIG. 4 is a side view of a printing unit of the recording apparatus according to the present invention when the recording sheet passes a rear end portion of the recording sheet.

FIG. 5 is a front view of a printing unit of the recording apparatus according to the present invention when the recording sheet passes a rear end portion of the recording sheet.

FIG. 6 is a plan cross-sectional view of the carriage when the recording apparatus according to the present invention has passed the rear end of the recording sheet.

FIG. 7 is a side view of a printing unit of the printing apparatus according to the present invention at the end of printing on the trailing edge of a print sheet.

FIG. 8 is a plan sectional view of the carriage at the end of printing on the trailing edge of the recording sheet of the recording apparatus according to the present invention.

FIG. 9 is a side view of a printing unit of a conventional recording apparatus.

FIG. 10 is a plan cross-sectional view of a carriage at the end of a recording sheet trailing edge printing section of a conventional recording apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Conveyance roller 2 Pinch roller 3 Discharge roller 4 Discharge spur 5 Platen 6 Recording head 7 Carriage 71 Head support part 72 Guide part 73 Cam 74 Spring 8 Guide shaft 9 Guide rail 10 Carriage drive motor 11 Timing belt 12, 13 Side plate 14 , 15 pin 16 PE sensor 17 PE sensor lever S Recording sheet

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Junichi Yoshikawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Tetsuya Ishikawa 3-30-2 Shimomaruko 3-chome, Ota-ku, Tokyo (72) Inventor Takashi Kasahara 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Fumihiro Goto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. ( 72) Inventor Ken Aoi 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 2C059 BB11 BB14 BB15 EE07 2C064 CC04 CC05 CC11 FF06

Claims (2)

[Claims] An image forming apparatus includes: a conveying unit configured to convey a sheet-shaped recording sheet; a recording head configured to record an image on the conveyed recording sheet; and a carriage that holds the recording head. In a serial-type printing apparatus that performs printing by scanning the carriage in the vertical direction, during normal printing, after the carriage scans and prints, the print sheet is conveyed by a predetermined amount, and the carriage scans again. To repeat the above, when printing on the trailing edge of the recording sheet, the trailing edge of the recording sheet is held by the transport unit, and the carriage is moved by a predetermined amount in the upstream direction in the transport direction of the recording sheet and scanned. A recording apparatus characterized in that recording is performed by using a recording apparatus. 2. A recording apparatus according to claim 1, wherein said recording head comprises a recording head having a plurality of recording colors in a recording sheet conveyance direction.