JP3979903B2 - Printer paper presser mechanism - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a paper pressing mechanism for a printer, and more particularly, to a paper pressing mechanism for pressing a printing paper so as not to float from a platen surface in an ink jet printer.
[0002]
[Prior art]
If the printing paper floats on the platen when printing data or the like on the printing paper with the printer, the print paper is rubbed by the ink ejection surface of the print head, resulting in image quality degradation. For this reason, various paper pressing mechanisms have been proposed, and representative examples thereof are described in JP-A-9-234920, JP-A-61-94780, and JP-A-59-12885. Yes.
[0003]
In particular, in a large format printer having a width of 100 inches, the width side end of the print sheet is likely to float, and the print head is easily caught by the lifted end of the print sheet, and 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 into practical use. 3 is an external perspective view of a principal part of a platen serving as a stamp screen bed, FIG. 4 is an external perspective view of a patch as a paper presser, and FIG. 5 shows a state in which a print 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 extends 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 are slidably attached along the circular grooves 11, 12. As shown in FIG. 6, the patch 2 is composed of a thin spring steel 21 straddling two round grooves 11 and 12, and a resin 22 that slides in the round grooves 11 and 12 is provided on both sides of the printing paper 3 in the feeding direction. Both ends in the feeding direction of the printing paper 3 are bent so as to receive the lead. The disk-shaped resin 22 is attached to the four corners of the thin plate spring steel 21, and the diameter of the resin 22 is selected to be slightly smaller than the diameter of the round grooves 11, 12. When it is slid to, a load is applied to lightly move by hand.
[0006]
When setting the printing paper 3, the patches 2 and 2 are left and right waiting, the printing paper 3 is pulled out from the platen 1, and the patches 2 and 2 are slid inward, as shown in FIG. The both ends of the printing paper 3 are sandwiched between the two. Thereby, the setting of the printing paper 3 is completed and printing is started. The patches 2 and 2 can prevent the printing paper 3 from being lifted at both ends, can eliminate friction between the printing paper 3 and the print head during printing, and can prevent the print head from being destroyed and printing defects.
[0007]
[Patent Document 1]
Japanese Patent Laid-Open No. 9-234920 (FIGS. 1 and 2, paragraph numbers 0020 to 0021)
[0008]
[Patent Document 2]
JP-A-61-94780 (FIGS. 1 and 2, page 2, lower right column to page 3, upper left column)
[0009]
[Patent Document 3]
JP 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 narrow, it becomes difficult to pinch both ends of the printing paper 3, and when the gap is widened, it is easy to pinch both ends of the printing paper 3. There is a problem of deteriorating.
[0011]
SUMMARY OF THE INVENTION Therefore, a main object of the present invention is to provide a paper holding mechanism for a printer that can easily hold a printing paper and can improve the printing quality by bringing the printing paper into close contact with the platen after the holding.
[0012]
[Means for Solving the Problems]
The present invention relates to a paper pressing mechanism that presses a width direction end of a printing paper in a printer that conveys the printing paper on the platen and performs printing by a printing head, and can slide on the platen in the width direction of the printing paper. The paper presser bracket includes a sliding part for sliding the print paper in the width direction on the platen, a presser knob for pressing by hand, and the presser knob being pressed. And a plate spring that lifts up against the platen and facilitates insertion of the end portion in the width direction of the printing paper and presses the end portion in the width direction of the printing paper in response to release of the press knob. To do.
[0013]
A groove extending perpendicularly to the transport direction is formed in the lower part of the front and rear ends of the platen in the transport direction of the printing paper, 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 portion of the thin metal plate, and the leaf springs are provided on both sides of the pair of grooves. .
[0015]
The presser knob is characterized in that a tip portion cut out by a front groove is formed by bending upward.
[0016]
DETAILED DESCRIPTION OF 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 cross-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 paper transport direction of the platen 4, and the paper guide plate 5 is provided with a transport roller 7 for transporting printing paper. The printing paper 3 is narrowed by the conveyance roller 7 and the pinch roller 50, and the printing paper 3 is conveyed from right to left in FIG. On the platen 4, there is provided a presser clamp 20 that is a presser fitting for pressing the end of the width direction of the printing paper against the platen 4, and this presser clamp 20 is along the platen 4 in the paper transport direction. Can be slid in a direction that intersects or is perpendicular to. Grooves 41 and 42 cut out at right angles are formed in the lower part of the front and rear ends of the platen 4 in the sheet conveying direction so as to extend in a direction perpendicular to the sheet conveying direction.
[0018]
The presser clamp 20 is made of, for example, a thin thin plate spring steel having a thickness of about 0.2 mm, and 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. The end portion includes bent portions 37 and 38 which are bent at a right angle upward to increase the strength. Two grooves 21 and 22 are formed in parallel on the side facing the conveying roller 7 of the presser clamp 20, and a pair of parallel grooves 31 and 32 are formed on the front side of the presser clamp 20 in the sheet conveying direction. A U-shaped groove 33 is formed on the front side of the grooves 31 and 32. These grooves 21, 22, 31 and 32 are separated into a wide portion 23 extending in the sheet conveying direction and narrow leaf springs 24 and 25 on both sides thereof. The end portions of the leaf springs 24 and 25 on the side of the conveying roller 7 are flipped upward so that the printing paper can easily enter the lower portion of the presser clamp 20.
[0019]
The end portion 26 on the conveying roller 7 side of the wide portion 23 is bent downward at a right angle, and further bent at a right angle toward the front side in the sheet conveying direction, and the tip thereof is a slit (not shown) formed in the sliding rod 35. ) Is inserted. The slide bar 35 slides in a direction orthogonal to the paper transport direction along a groove 41 formed in a lower portion of the platen 4 on the rear side in the transport direction.
[0020]
The front end portion 29 of the presser clamp 20 on the front side in the paper conveyance direction is also bent downward at a right angle and further bent at a right angle on the rear side in the paper conveyance direction, and the front 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 orthogonal to the paper transport direction along a groove 42 formed in a lower portion on the front side in the transport direction of the platen 4. The sliding rod 36 is formed so as to be longer than the sliding rod 35 on the conveying roller 7 side, but it may be the same length. Further, the presser clamp 20 can be slid stably without being detached from the platen 4.
[0021]
Furthermore, the front end portion in the sheet conveyance direction cut out by the groove 33 of the presser clamp 20 is bent upward to form a presser knob 30. Both end portions 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 by the lever principle 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 addition, since the end portions of the leaf springs 24 and 25 on the side of the conveying roller 7 are flipped upward, it is easy to insert the printing paper under the presser clamp 20.
[0022]
In the paper presser mechanism formed as described above, two presser clamps 20 and 20 are mounted on the platen 4. Then, the printing paper is conveyed onto the platen 4 by the conveying roller 7, and one presser clamp 20 is slid from the left side toward the conveying roller 7 to approach the printing paper and presses the pressing knob 30 to press the leaf springs 24, 25. The printing paper is caused to enter a gap formed between the leaf spring 25 of the presser clamp 20 and the platen 4.
[0023]
Similarly, the other presser clamp 20 is slid from the right side toward the conveying roller 7 to approach the print paper, presses the presser knob 30 and lifts the leaf springs 24 and 25, and presses the print paper into the presser clamp 20. The gap is formed between the leaf spring 24 and the platen 4. Accordingly, both ends of the printing paper in the width direction can be pressed onto the platen 4 by the two presser clamps 20. Therefore, both ends of the printing paper are not lifted during printing, and the printing quality is not deteriorated.
[0024]
Note that the widths of the leading end 29 on the other side of the presser clamp 20 and the end 26 on the conveying roller 7 side are selected to be equal, and the end in the width direction of the printing paper conveyed by these portions is locked. Even when the printing paper is being conveyed, the printing paper is not shaken in the direction orthogonal to the paper conveying direction.
[0025]
Although one embodiment of the present invention has been described with reference to the drawings, the present invention is not limited to the illustrated embodiment. Various modifications can be made to the illustrated embodiment within the same scope or equivalent scope as the present invention. Some of them will be described by way of example.
[0026]
In the embodiment shown in FIG. 1, the leaf springs 24 and 25 having the width are provided on both sides of the wide portion 23 of the presser clamp 20, but this is also used as the left and right presser fittings to reduce the manufacturing cost. In the case of using the left and right holding metal fittings, one of them may be omitted.
[0027]
Further, the wide portion 23 and the leaf springs 24 and 25 may have the same width.
[0028]
Further, the printer may be one that prints by fixing the print head and moving the printing paper in the width direction.
[0029]
【The invention's effect】
As described above, according to the present invention, the sheet presser bracket is provided so as to be slidable on the platen in the width direction of the print sheet, and the sheet presser bracket is slid in the width direction of the print sheet on the platen. The sliding part, the presser knob pressed by hand, and the pressing of the presser knob lifted up against the platen to facilitate the insertion of the width direction end of the printing paper, and the presser of the presser knob was released. Correspondingly, by providing a leaf spring that presses the end in the width direction of the paper, it is possible to easily sandwich the printing paper, and after the clamping, the printing paper can be brought into close contact with the platen to improve the printing quality.
[0030]
In addition, by providing a pair of leaf springs on both sides in the transport direction with the presser knob as the center, it is possible to use both ends of the printing paper in the width direction as presser brackets, and when manufacturing the left and right presser brackets individually. Compared to the cost.
[Brief description of the drawings]
FIG. 1 is an external perspective view of a sheet pressing mechanism according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of the paper pressing mechanism shown in FIG.
FIG. 3 is an external perspective view of a main part of a platen serving as a seal screen bed.
FIG. 4 is an external perspective view of a patch that is a sheet presser.
5 is an external view showing a state in which a print sheet is pressed by the patch of FIG.
FIG. 6 is a cross-sectional view of a patch.
[Explanation of symbols]
4 Platen, 5, 6 Paper guide plate, 7 Transport roller, 20 Presser clamp, 21, 22, 31, 32, 33, 41, 42 Groove, 23 Wide portion, 24, 25 Leaf spring, 26, 29 End , 30 Presser knob, 35, 36 Slide bar.

Claims (4)

In a printer that conveys printing paper on a platen and performs printing with a print head, a paper pressing mechanism that presses a width direction end of the printing paper,
Including a sheet pressing metal fitting slidably provided on the platen in the width direction of the printing paper,
The sheet presser fitting is provided on the platen in response to pressing of the presser knob, a sliding part for sliding in the width direction of the printing paper on the platen, a presser knob for pressing by hand. And a leaf spring that floats up and facilitates insertion of the end portion in the width direction of the print sheet and presses the end portion in the width direction of the sheet in response to the release of the press knob. Printer paper presser mechanism. A groove extending perpendicularly to the transport direction is formed at the lower part of the front and rear ends of the platen in the transport direction of the paper,
The paper pressing mechanism of a printer 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 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,
The paper pressing mechanism of a printer according to claim 3, wherein the leaf springs are provided on both sides of the pair of grooves. 6. The paper pressing mechanism of a printer according to claim 5, wherein the pressing knob is formed by bending a tip portion cut out by the front groove.

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