JP2004090538A - Paper hold mechanism of printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper hold mechanism of a printer which facilitates catching of a printing paper and can improve the print quality by adhering the printing paper to a platen after the paper is caught. <P>SOLUTION: The paper hold mechanism has a pair of holding clamps 20 set slidably on the platen 4 in a direction orthogonal to a transfer direction of the printing paper 3. Sliding rods 35 and 36 of the holding clamps 20 set at ends in a front-and-rear direction of the transfer direction slide along slots 41 and 42 formed in front and rear lower ends of the paper transfer direction of the platen 4, thereby pressing a hold knob 30. Consequently, leaf springs 24 and 25 are lifted to facilitate an insertion of width side ends of the printing paper 3. The width side ends of the paper are held in consequence of releasing the pressing of the hold knob 30. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a paper holding mechanism of a printer, and more particularly, to a paper holding mechanism that presses a printing paper so as not to float above a platen surface in an inkjet printer.
[0002]
[Prior art]
If the printing paper floats on the platen when printing data or the like on the printing paper by the printer, the printing paper is rubbed by the ink ejection surface of the printing head, thereby deteriorating the image quality. For this reason, various paper holding mechanisms have been conventionally proposed, and typical examples thereof are described in JP-A-9-234920, JP-A-61-94780 and JP-A-59-12885. I have.
[0003]
In particular, in a large format printer having a printing paper width of 100 inches, the width side end of the printing paper is easily lifted, and the print head is caught by the raised printing paper end, so that a paper feed jam is likely to occur. .
[0004]
In order to prevent such a paper feeding jam, a paper pressing mechanism as shown in FIGS. 3 to 6 has been put to practical use. 3 is an external perspective view of a main part of a platen serving as a printing screen bed, FIG. 4 is an external perspective view of a patch serving as a paper presser, and FIG. 5 shows a state in which printing paper is pressed by the patch of FIG. FIG. 6 is an external view, and FIG. 6 is a cross-sectional view of the patch.
[0005]
As shown in FIG. 3, the platen 1 is formed so as to extend in a direction perpendicular to the feeding direction of the printing paper 3, and the platen 1 has two round grooves 11, 12 before and after the feeding direction of the printing paper 3. Is formed. Two patches 2, 2 for pressing the width direction end of the printing paper 3 along the circular grooves 11, 12 are slidably mounted. As shown in FIG. 6, the patch 2 is made of a thin plate spring steel 21 that straddles the two round grooves 11 and 12, and a resin 22 that slides in the round grooves 11 and 12 is provided on both sides in the feeding direction of the printing paper 3. Both ends in the feed direction of the printing paper 3 are bent so as to receive the core. The disk-shaped resin 22 is attached to the four corners of the thin leaf spring steel 21, and the diameter of the resin 22 is selected to be slightly smaller than the diameter of the round grooves 11 and 12. When it is slid, a load that can be moved lightly by hand is applied.
[0006]
When setting the printing paper 3, the patches 2 and 2 are left and right standing by, the printing paper 3 is pulled out from the platen 1 toward the front side, and each patch 2 and 2 is slid inward, as shown in FIG. Between both ends of the printing paper 3. This completes the setting of the printing paper 3 and starts printing. The patches 2 and 2 prevent the printing paper 3 from floating at both ends, can prevent the printing paper 3 from rubbing with the print head at the time of printing, and can prevent the destruction of the print head and the printing failure.
[0007]
[Patent Document 1]
JP-A-9-234920 (FIG. 1, FIG. 2, paragraphs 0020 to 0021)
[0008]
[Patent Document 2]
JP-A-61-94780 (FIG. 1, FIG. 2, lower right column of page 2 to upper left column of page 3)
[0009]
[Patent Document 3]
JP-A-59-12885 (FIG. 2, page 2, upper right column to lower left column)
[0010]
[Problems to be solved by the invention]
However, in the ink jet printer, the gap between the platen 1 and the print head is only about 1 mm, and the gap between the patch 2 and the platen 1 is fixed in the conventional paper pressing mechanism shown in FIGS. When the gap is small, it is difficult to pinch both ends of the printing paper 3. When the gap is widened, it is easy to pinch both ends of the printing paper 3. There is a problem of deterioration.
[0011]
SUMMARY OF THE INVENTION Therefore, a main object of the present invention is to provide a paper press mechanism of a printer which can easily sandwich printing paper and can improve printing quality by bringing the printing paper into close contact with a platen after the sandwiching.
[0012]
[Means for Solving the Problems]
The present invention relates to a paper pressing mechanism that presses an end portion in a width direction of a printing paper in a printer that conveys a printing paper on a platen and performs printing by a print head, and is slidable on the platen in a width direction of the printing paper. The paper holding member includes a sliding portion for sliding on the platen in the width direction of the printing paper, a pressing knob for pressing by hand, and a pressing knob for pressing the pressing knob. A leaf spring that lifts up with respect to the platen to facilitate insertion of the widthwise end of the printing paper, and presses the widthwise end of the printing paper in response to the release of the presser knob. I do.
[0013]
A groove extending perpendicular to the conveying direction is formed in a lower portion of the platen at the front and rear ends of the printing paper in the conveying direction, and the sliding portion includes a sliding member that slides along the groove.
[0014]
The presser fitting includes a pair of grooves cut out in parallel along the rear side and the front side in the transport direction except for the central part of the thin metal plate, and the leaf spring is provided on both sides of the pair of grooves. .
[0015]
The pressing knob is characterized in that a front end portion cut out by the front groove is bent upward and formed.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is an external perspective view of a paper pressing mechanism according to an embodiment of the present invention, and FIG. 2 is a sectional view of the paper pressing mechanism shown in FIG.
[0017]
In FIG. 1, paper guide plates 5 and 6 are provided before and after the platen 4 in the paper transport direction, and the paper guide plate 5 is provided with a transport roller 7 for transporting print paper. When the print paper 3 is narrowed by the transport rollers 7 and the pinch rollers 50, the print paper 3 is transported from right to left in FIG. On the platen 4, there is provided a holding clamp 20, which is a holding metal member for holding the widthwise end of the printing paper from rising to the platen 4, and the holding clamp 20 is moved along the platen 4 in the paper transport direction. Is slidable in a direction intersecting or orthogonal to. At the lower part of the front and rear ends of the platen 4 in the sheet conveyance direction, grooves 41 and 42 cut at right angles are formed so as to extend in a direction perpendicular to the sheet conveyance direction.
[0018]
The holding clamp 20 is made of, for example, a thin leaf spring steel having a thickness of about 0.2 mm, has a wide width on the side facing the conveyance roller 7 and a narrow width on the front side in the paper conveyance direction, and has a narrow portion in the width direction. The ends include folds 37, 38 bent upward at right angles to increase strength. Two grooves 21 and 22 are formed in parallel on the side of the holding clamp 20 facing the conveyance roller 7, and a pair of parallel grooves 31 and 32 are formed on the front side of the holding clamp 20 in the sheet conveyance direction. A U-shaped groove 33 is formed in front of these grooves 31 and 32. These grooves 21, 22, 31, and 32 separate the wide portion 23 extending in the paper transport direction from the narrow leaf springs 24 and 25 on both sides thereof. The ends of the leaf springs 24 and 25 on the side of the transport roller 7 are flipped upward so that the printing paper can easily enter the lower part of the holding clamp 20.
[0019]
The end 26 of the wide portion 23 on the side of the conveying roller 7 is bent downward at a right angle, further bent forward at a right angle in the paper conveying direction, and the leading end thereof is formed by a slit (not shown) formed in a sliding rod 35. ) Is inserted. The slide bar 35 slides in a direction perpendicular to the sheet conveyance direction along a groove 41 formed in a lower portion of the platen 4 on the rear side in the conveyance direction.
[0020]
The front end portion 29 of the presser clamp 20 on the front side in the paper transport direction is also bent downward at a right angle, and further bent back on the rear side in the paper transport direction at a right angle, and the distal end portion is formed on a sliding rod 36 as a sliding member. It is inserted into a slit (not shown). The slide bar 36 slides in a direction perpendicular to the sheet conveyance direction along a groove 42 formed in a lower portion of the platen 4 on the front side in the conveyance direction. The sliding bar 36 is formed to be longer than the sliding bar 35 on the transport roller 7 side, but may have the same length. Further, the presser clamp 20 can slide stably without detaching from the platen 4.
[0021]
Further, a front end portion of the press clamp 20 cut out by the groove 33 on the front side in the sheet transport direction is bent upward to form a press knob 30. Both ends in the width direction of the presser knob 30 are bent downward for reinforcement so that the presser knob 30 itself does not bend when pressed down from above. When the presser knob 30 is pressed from above, the leaf springs 24 and 25 are lifted up by the principle of leverage, with the boundary between the presser knob 30 and the wide portion 23 and the end on the side of the conveying roller 7 as a fulcrum. There is a gap in In addition, since the ends of the plate springs 24 and 25 on the side of the transport roller 7 are flipped up, it is easy to insert the printing paper under the holding clamp 20.
[0022]
In the paper press mechanism formed as described above, two press clamps 20 are mounted on the platen 4. Then, the printing paper is transported onto the platen 4 by the transporting roller 7, and one holding clamp 20 is slid from the left side toward the transporting roller 7 to approach the printing paper, and the pressing knob 30 is pressed to release the leaf springs 24, 25. Is raised, and the printing paper is caused to enter the gap formed between the plate spring 4 of the holding clamp 20 and the platen 4.
[0023]
Similarly, the other holding clamp 20 is slid from the right side toward the conveying roller 7 to approach the printing paper, and presses the holding knob 30 to lift the plate springs 24 and 25 to hold the printing paper. It is caused to enter the gap formed between the leaf spring 24 and the platen 4. As a result, both ends in the width direction of the printing paper can be pressed onto the platen 4 by the two holding clamps 20, so that both ends of the printing paper do not rise during printing, and the printing quality does not deteriorate.
[0024]
The width of the tip portion 29 on the other side of the presser clamp 20 and the width of the end portion 26 on the side of the conveying roller 7 are selected to be equal, and the width direction ends of the printing paper conveyed by these portions are locked. Even when the printing paper is being conveyed, it does not shake in a direction orthogonal to the paper conveyance direction.
[0025]
One embodiment of the present invention has been described with reference to the drawings, but the present invention is not limited to the illustrated embodiment. Various changes can be made to the illustrated embodiment within the same or equivalent scope as the present invention. Some of them will be exemplified and described.
[0026]
In the embodiment shown in FIG. 1, the leaf springs 24, 25 having a wide width are provided on both sides of the wide portion 23 of the holding clamp 20, but this is also used as left and right holding metal fittings to reduce the manufacturing cost. However, in the case of using the right and left holding metal fittings, one of them may be omitted.
[0027]
The wide portion 23 and the leaf springs 24 and 25 may have the same width.
[0028]
Further, the printer may be a printer in which the print head is fixed and the print paper is moved in the width direction to perform printing.
[0029]
【The invention's effect】
As described above, according to the present invention, the paper holding member provided slidably on the platen in the width direction of the printing paper, the paper holding member for sliding in the width direction of the printing paper on the platen The sliding part, the presser knob pressed by hand, and the pressing of the presser knob lifts up the platen in response to the pressing of the presser knob, facilitating the insertion of the width direction end of the printing paper, and releasing the presser knob. By providing a leaf spring that presses the widthwise end of the paper in response, the printing paper can be easily sandwiched, and after the sandwiching, the printing paper can be brought into close contact with the platen to improve printing quality.
[0030]
In addition, by providing a pair of leaf springs on both sides in the transport direction with the press knob as the center, the press spring can also be used as a press fitting for pressing the widthwise end portion of the printing paper from the left and right. In comparison, costs can be reduced.
[Brief description of the drawings]
FIG. 1 is an external perspective view of a paper pressing mechanism according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of the sheet pressing mechanism shown in FIG.
FIG. 3 is an external perspective view of a main part of a platen serving as an imprint screen bed.
FIG. 4 is an external perspective view of a patch serving as a paper presser.
FIG. 5 is an external view showing a state where printing paper is pressed by the patch of FIG. 4;
FIG. 6 is a sectional view of a patch.
[Explanation of symbols]
4 platen, 5, 6 paper guide plate, 7 transport roller, 20 holding clamp, 21, 22, 31, 32, 33, 41, 42 groove, 23 wide part, 24, 25 leaf spring, 26, 29 end , 30 Holding knob, 35, 36 Sliding rod.

Claims (4)

In a printer that conveys printing paper on a platen and prints with a print head, a paper pressing mechanism that presses a width direction end of the printing paper,
Including a paper presser provided slidably on the platen in the width direction of the printing paper,
The paper presser fitting includes a sliding portion for sliding on the platen in the width direction of the printing paper, a presser knob for pressing by hand, and a platen in response to pressing the presser knob. A leaf spring that lifts the printing paper to facilitate insertion of the widthwise end of the printing paper, and presses the widthwise end of the paper in response to release of the pressing of the press knob. , Printer paper holding mechanism. At the lower part of the front and rear ends of the platen in the transport direction of the sheet, a groove extending perpendicular to the transport direction is formed,
The paper pressing mechanism according to claim 2, wherein the sliding portion includes a sliding member that slides along the groove. The presser fitting includes a pair of grooves cut in parallel along the rear side and the front side in the transport direction except for the center of the thin metal plate,
The paper press mechanism according to claim 3, wherein the leaf springs are provided on both sides of the pair of grooves. 6. The paper press mechanism of the printer according to claim 5, wherein the press knob is formed by bending an end portion notched by the front groove upward.

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