JPH0740144U - Paper press structure for inkjet printers - Google Patents

Abstract

(57) [Abstract] [Purpose] A paper holding structure for an inkjet printer that can press the entire width of a recording sheet with a uniform force so that the recording sheet is not lifted from the plane of the bed and is fed in close contact with the plane of the bed. I will provide a. [Structure] The recording paper P is fed along the plane of the bed 101, and a carriage 11 having an ink ejecting unit at a position facing the plane of the bed 101 is moved in a direction perpendicular to the feeding direction of the paper so that the recording paper P is moved. In the ink jet printer for performing the recording, plural leaf springs 2 are arranged in parallel along the edge of the bed 101. One end of each leaf spring 2 is attached to the housing, and the other end, which is a free end, is an inclined portion formed at the edge of the bed 101 on the recording paper supply side and serving as a recording paper entrance.
It is pressed against the bed surface slightly on the paper feed direction side from 101a.
The recording sheet P is sent while being pressed against the bed plane by the free ends of the plurality of leaf springs 2.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inkjet printer, and more particularly, to a paper pressing structure that allows recording paper to be fed in close contact with the bed surface without floating from the bed surface.

[0002]

[Prior art]

 In a conventional inkjet printer, for example, as shown in FIG. 4, a recording sheet P is flatly regulated by a sweep-side rubber roller 202 driven by a motor 201 and a feeding-side rubber roller 203 that cooperates with the sweep-side rubber roller 202, and a direction f shown in the figure is obtained. On the other hand, the carriage 205 having the ink ejecting unit 204 mounted thereon is mounted on the guide shaft 206 such that the carriage 205 can move forward and backward, and the drive belt 207 fixed to the carriage 205 is driven by the motor 208. Recording is performed on the recording paper P by moving the guide shaft 206 in a direction s as shown in the figure, which is perpendicular to the feed direction, and ejecting ink droplets from the ink ejecting unit 204 (Japanese Patent Publication No. 4-. No. 72697).

[0003]

[Problems to be solved by the device]

 By the way, in the paper feeding mechanism as described above, it is difficult to accurately feed the recording paper P until the leading end of the recording paper P reaches the sweep-side rubber roller 202, and therefore, from the leading end of the paper to the printable area. The distance becomes longer.

Such a problem is that a bed having a flat upper surface is arranged between the feeding-side rubber roller 203 and the sweep-side rubber roller 202, and the feeding-side rubber roller 203 is driven by a motor so that the recording paper P is betted. If you adopt a structure that feeds along the plane of, it will be solved once.

However, the distance from the tip of the ink ejecting nozzle of the ink ejecting unit 204 to the recording paper P needs to be an extremely short distance such as 0.7 mm, and in order to maintain the printing quality, the distance is always kept. Need to keep constant. If the recording paper P is simply fed out from the feeding-side rubber roller 203, the recording paper P is lifted from the flat surface of the bed, so that the relative distance to the ink ejection nozzles is not constant and some measure is required.

As a countermeasure against this, a large number of through holes are provided in the bed surface, and during printing, air is sucked from the through holes by vacuum so that the recording paper P is tightly adhered to the bed surface, and the suction is stopped at the time of conveyance. It is conceivable that the above configuration or a configuration in which similar contact and release are performed by electrostatic force, but there is a disadvantage that the configuration becomes complicated and the transport speed decreases.

On the other hand, as a simpler configuration, a configuration may be considered in which the entire width of the recording paper P fed by the feeding-side rubber roller 203 is pressed against the bed plane by a single leaf spring. At this time, since the pressure of the leaf spring acts as a load for feeding the paper, the entire width of the recording paper P is uniformly pressed with an appropriate force so that the paper feeding is not hindered and the recording paper P is in close contact with the bed plane. There must be. However, since the total width of the recording paper P is 21 cm on the short side of row A No. 4, it is necessary to uniformly press the entire width of the recording paper P with an appropriate force by using one leaf spring. Even if you raise it, realization is not easy. If the leaf spring is curved with respect to the plane of the bed, the pressing force is weakened over the continuous wide area of the peripheral portion of the recording paper P or conversely the peripheral portion because the width of the leaf spring is long. At that portion, the paper floats and the print quality deteriorates.

The present invention solves the above-mentioned problems due to the paper pressing structure using such a leaf spring, and an object thereof is to prevent the recording paper from sticking to the plane of the bed and sticking to the plane of the bed. Another object of the present invention is to provide a paper pressing structure for an inkjet printer that can press the entire width of the recording paper with a uniform force so that the recording paper is fed.

[0009]

Means for Solving the Problems In order to achieve the above object, the present invention provides a carriage that feeds a recording sheet along a plane of a bed and mounts an ink jet unit at a position facing the plane of the bed. In an inkjet printer that records on the recording paper by moving it in a direction perpendicular to the feeding direction of the recording paper, one end is attached to a housing, and the other free end is the recording paper supply side of the bed. A plurality of leaf springs are arranged in parallel along the edge of the bed so as to be pressed against the bed surface slightly on the paper feeding direction side of the inclined portion which is formed at the edge and serves as a recording paper entrance.

[0010]

[Action]

 The leading edge of the sent recording paper enters from the inclined part formed on the edge of the bed on the supply side of the recording paper, presses into the gap between each leaf spring and the bed plane, and is set by the free end of each leaf spring. The ink is ejected along the bet plane while being pressed against the bet plane with an appropriate force, and recording is performed by the ink ejection unit mounted on the carriage.

[0011]

【Example】

 Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic plan view of a main part of an inkjet printer to which a paper pressing structure according to the present invention is applied, and FIG. 2 is a schematic side view of the same part.

In FIGS. 1 and 2, 101 is a bed, the upper surface of which is processed flat, and the recording paper P is conveyed on this plane of the bed 101 in the direction f shown in the figure. A bevel 101 has an inclined portion 101a serving as a recording sheet entrance on the edge of the recording sheet P on the side where the recording sheet P is supplied, and the leaf spring 2 for pressing the sheet, which is made of a metal plate such as stainless steel, is A plurality of sheets (four sheets in this embodiment) are arranged in parallel along the edge. One end of each leaf spring 2 is attached to a casing (not shown), and the other end, which is a free end, is formed by the inclined portion 101a. It extends slightly to the bed surface on the paper feed direction side. All of these leaf springs 2 are pressed from above by one round bar 5, so that the free ends of the leaf springs 2 extending to the bed surface are in pressure contact with the bed surface.

On the other hand, on the side of the carriage 11, which is mounted on the two guide shafts 6 so as to be able to move back and forth, slightly opposite the free end of the leaf spring 2 on the plane of the plate, in the paper feed direction side, The ejection unit 11a is mounted, and the carriage 11 can be moved in the width direction of the recording paper P by moving the carriage 11 along the guide shaft 6 in the s direction shown in the figure by a belt (not shown). .

Further, on the sweep side of the sheet, there is a sweep side rubber roller 7 driven by a motor (not shown) and a wheel 9 pivotally supported so as to engage with the sweep side rubber roller 7. The tip is sandwiched in the gap between the sweep-out side rubber roller 7 and the wheel 9, and is discharged to the outside of the printer housing by the rotation of the rubber roller 7.

FIG. 3 is an external perspective view showing a more detailed configuration example in the vicinity of one sheet pressing leaf spring 2. As shown in the figure, a pair of pawls 2a is provided at one end of the leaf spring 2, and the pawl insertion port 102 provided in the printer housing (also referred to as a printer engine) 1 is engaged with the pawl 2a. Further, the leaf spring 2 of this example functions as a mounting member of the pinch roller 3 and a member for urging the pinch roller 3 in addition to the paper pressing, and is substantially U for loosely inserting the shaft 3b of the pinch roller 3. A bearing portion 2d having a V-shaped groove and a sub leaf spring 2b for pressing both ends of the pinch roller 3 are integrally formed. An opening 2c is provided in the substantially central portion so that the roller portion 3a of the pinch roller 3 projects from the lower surface of the leaf spring 2. The sub leaf spring 2b also has an opening 2c, and the roller portions 3a on both ends of the pinch roller 3 also project from the lower surface of the leaf spring 2. A rubber roller 4 for feeding the recording paper is provided below the leaf spring 2 at a position facing the pinch roller 3, and the pinch roller 3 is pressed against the rubber roller 4 side by the sub leaf spring 2b. The recording paper is fed out through the gap between the rubber roller 4 and the pinch roller 3, and resists the pressing force of the leaf spring 2 from the gap between the inclined portion 101a formed on the edge of the bed 101 and the free end of the leaf spring 2. Then, it advances to the bed plane and is sent while closely contacting on the bed plane.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various other additions and modifications can be made. For example, in the above embodiment, four plate panels 2 were used, but it goes without saying that the number is not limited to four.

[0018]

[Effect of device]

 As described above, according to the present invention, the entire width of the recording paper is shared by the plurality of leaf springs and pressed against the bed plane, so that the width of each leaf spring is larger than that when one leaf spring is used. As a result, the width of the continuous portion where the pressing force is weakened is shortened and the floating amount of the recording paper is reduced accordingly, even if each leaf spring is slightly curved due to the work precision. As a result, the entire width of the recording paper can be surely brought into close contact with the plane of the bed, and the print quality can be kept constant.

[Brief description of drawings]

FIG. 1 is a schematic plan view of a main part of an inkjet printer to which a paper pressing structure according to the present invention is applied.

FIG. 2 is a schematic side view of a main part of an inkjet printer to which the paper pressing structure according to the present invention is applied.

FIG. 3 is an external perspective view showing a more detailed configuration example in the vicinity of one sheet pressing leaf spring.

FIG. 4 is a diagram illustrating the configuration of a conventional inkjet printer.

[Explanation of symbols]

 2 ... Leaf spring for paper pressing 5 ... Round bar for forming fulcrum of leaf spring for paper pressing 6 ... Guide shaft for carriage 7 ... Rubber roller for sweeping out 9 ... Wheel 11 ... Carriage 101 ... Bed 101a ... Inclined portion P ... Recording sheet

Claims (1)

[Scope of utility model registration request] 1. A recording paper is fed along a plane of a bed, and a carriage having an ink ejecting unit at a position facing the plane of the bed is moved in a direction perpendicular to the feeding direction of the recording paper to move the recording paper. In an inkjet printer that records on top, one end is attached to the housing and the other end, which is the free end, is slightly fed from the inclined part that is the recording paper entrance formed on the edge of the bed on the recording paper supply side. A paper pressing structure for an ink jet printer, characterized in that a plurality of leaf springs pressed against the bet surface on the direction side are arranged in parallel along the edge of the bed.