JPH0740145U - Paper floating prevention mechanism for inkjet printers - Google Patents

Abstract

(57) [Summary] [Purpose] The recording quality is improved by allowing the recording paper to be fed in close contact with the bed surface. The recording paper P is fed along the plane of the bed 101, and a carriage 11 having an ink ejecting unit 11a mounted at a position facing the plane of the bed 101 is moved in a direction perpendicular to the feeding direction of the paper. In an inkjet printer that performs recording on top, the recording paper P is pressed by the leaf spring 2 on the bed plane on the paper feed side. Further, the contact position between the rubber roller 7 for sweeping out the recording paper P traveling on the bed plane and the wheel 9 cooperating with the rubber roller 7 is set slightly below the bed plane, and the rubber roller 7 is sandwiched between the rubber roller 7 and the wheel 9. A force for pulling the recording paper P sent in a downward direction from the plane of the bed is generated to prevent the recording paper P from floating.

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 sheet floating prevention mechanism of an inkjet printer that allows a recording sheet to be fed without floating from a bed surface.

[0002]

[Prior art]

 In a conventional inkjet printer, for example, as shown in FIG. 6, a recording sheet P is flatly regulated by a sweeping-side rubber roller 202 driven by a motor 201 and a feeding-side rubber roller 203 that cooperates with the sweeping-side rubber roller 202, and a direction f shown in the figure 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. The recording medium is moved along the guide shaft 206 in a direction s as shown in the figure at right angles to the feeding direction, and ink droplets are ejected from the ink ejecting unit 204 to perform recording on the recording paper P (Patent Fair No. 4-72697).

[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-out 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 is 0.7 mm, which is extremely narrow, and in order to maintain the print quality, it is necessary to keep the distance constant. There is. Therefore, if the recording paper P is simply fed 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 between the recording paper P and the ink ejection nozzle is not constant and some measures are required. .

Various measures are conceivable as such a measure, and as a very simple structure, a measure for pressing the paper with a leaf spring can be considered. That is, press the free end of the leaf spring, one end of which is attached to the housing, to the bet surface slightly on the paper feed direction side from the inclined portion that is the recording paper entrance formed on the edge of the recording paper supply side of the bed. Thus, the recording paper is sent out along the plane of the bed.

However, even if such a paper-pressing leaf spring is actually used, the recording paper runs while floating up from the bed surface, depending on the paper quality, etc. A phenomenon was observed in which the print quality deteriorated to some extent when the distance was shortened below a predetermined distance.

The present invention has been proposed in view of the above circumstances, and an object thereof is to provide a sheet floating prevention mechanism for an inkjet printer, in which a recording sheet is reliably fed along a bed surface. Especially.

[0009]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention feeds a recording sheet along a plane of a bed and mounts a carriage having an ink ejecting unit at a position facing the plane of the bed in a direction perpendicular to the feeding direction of the recording sheet. In an ink jet printer that moves in the direction to record on the recording sheet, a rubber roller for sweeping the recording sheet traveling on the flat surface of the bed and a wheel or the like that presses the rubber roller through the recording sheet when sweeping the recording sheet. The position of contact with the member is configured to be slightly lower than the plane of the bed.

[0010]

[Action]

 The leading edge of the recording paper that has traveled on the flat surface of the bed is sandwiched in the gap between the rubber roller for sweeping the recording paper and the member such as the wheel, and is discharged to the outside of the printer housing by the rotation of the rubber roller. Since the force pulling the recording paper below the bed plane works, the recording paper is prevented from rising and the recording paper is fed along the bed plane.

[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 floating prevention mechanism 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. An inclined portion 101a serving as a recording paper entrance is provided at the edge of the bet 101 on the side of the recording paper P to be supplied, and a plurality of leaf springs 2 for pressing the paper are provided along the edge of the bet 101 (in this embodiment, in the present embodiment). (4 sheets) are arranged in parallel, one end of each leaf spring 2 is attached to a casing (not shown), and the other end, which is a free end, extends from the inclined portion 101a to a bed surface slightly on the paper feeding direction side. . All of these leaf springs 2 are pressed from above by one round bar 5 extending in the horizontal direction in the arrangement direction of the leaf springs 2, so that the free ends of the leaf springs 2 extending to the bet surface are betted. It comes in pressure contact with the 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 paper, there are a sweep side rubber roller 7 driven by a motor (not shown), and a wheel 9 pivotally supported so as to engage with the rubber roller 7. Here, the contact position between the rubber roller 7 and the wheel 9 is adjusted to be slightly lower than the plane of the bed 101 as shown in FIG. As a result, when the leading edge of the recording paper P that has moved on the bed plane is caught in the gap between the sweep-side rubber roller 7 and the wheel 9, and the rubber roller 7 is rotated to be discharged to the outside of the printer housing, recording is performed. A force pulling the sheet P below the bed plane is applied, and the recording sheet P is pushed up to the bed plane by the leaf spring 2 on the sheet feeding side of the bed 101, so that the recording sheet P is lifted. It is possible to prevent the recording sheet P from being brought into close contact with the flat surface of the bed and to feed it.

In this embodiment, four sets of shafts each having one wheel 9 attached to both ends are arranged and arranged in parallel with the edge of the bed 101 to share each part of the recording paper P. Although the structure in which the rubber roller 7 is pressed is adopted, it goes without saying that the number of shafts to which the two wheels 9 are attached is not limited to four. Further, instead of the wheel 9, a rubber roller similar to the rubber roller 7 may be used.

FIG. 3 is an external perspective view showing a more detailed configuration example of the vicinity of one sheet pressing leaf spring 2. The leaf spring 2 shown in the same drawing has a pair of bearings, which are formed as openings in the substantially central portion of a metal plate such as stainless steel, and are then opened to bend the protrusions so that a bearing portion 2d is projected. A pair of sub leaf springs 2b are formed by forming a substantially U-shaped groove at a position adjacent to the bearing portion 2d, and a pair of claws 2a is further provided at one end of the pair of sub leaf springs 2a. It is also locked to a claw insertion opening 102 provided in the engine 1. The round bar 5 presses the substantially central portion from above.

The pinch roller 3 has a large diameter roller portion 3a at both ends and a central portion, and a thin diameter shaft 3b between the roller portions 3a. The shaft 3b is loosely inserted into the substantially U-shaped groove of the bearing 2d so that the lower portion of the roller 3a projects from the lower surface of the leaf spring 2 through the opening 2c. The auxiliary leaf springs 2b press the roller portions 3a at both ends.

A rubber roller 4 for feeding the recording paper, which is rotated by a motor (not shown), is provided below the plate spring 2 at a position facing the pinch roller 3, and the pinch roller 3 is driven by the auxiliary plate spring 2b. Pressed to the side. The recording paper is fed through a 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.

FIG. 4 is an external perspective view showing a more detailed configuration example near the wheel 9. In the figure, reference numeral 110 denotes a wheel bearing member that is integrally formed with the housing, has a pair of arms 110a, and a substantially U-shaped groove 110b is formed at the end of each arm 110a. It The shaft 8 to which the two wheels 9 are attached is loosely inserted into the groove 110b formed in the arm 110a, and the substantially central portion of the shaft 8 travels on the flat surface of the bed 101 by the leaf spring 10. It is pressed against the rubber roller 7 side for sweeping out the paper P. The leaf spring 10 is set in the housing 1 by inserting the claw 10a provided at one end thereof into the insertion opening 111, and the bent portion 10b engaging with the shaft 8 is formed at the other end side. Has been done.

In the example of FIG. 4, a wheel called a star wheel is used as the wheel 9. This is because by making contact with the recording paper P at points instead of lines, the influence on ink droplets on the recording paper P is further reduced.

FIG. 5 is an external perspective view of the printer housing 1 integrally formed by injection molding. Reference numeral 101 is a bed, 101a is an inclined portion of the printer housing, and 102 is an insertion port to which the claw 2a of the paper pressing leaf spring 2 is attached. , 103 and 104 are locking tools for mounting the round bar 5, 105 is a guide piece for guiding the recording paper to the feeding side rubber roller 4, 106 and 107 are locking for mounting the guide shaft 6 of the carriage. Tool 108 is a hole for mounting the drive shaft of the rubber roller 4 on the feeding side, 109 is a hole for mounting the drive shaft of the rubber roller 7 on the sweeping side, 110 is a bearing member for the wheel, and 111 is a hole for inserting the claw 10a of the leaf spring 10. Is. The printer housing 1 is made of, for example, ABS or a resin in which polycarbonate or glass beads are mixed.

[0023]

[Effect of device]

 As described above, in the present invention, the position where the rubber roller for sweeping out the recording sheet traveling on the flat surface of the bed and the member such as the wheel or the rubber roller that presses against the rubber roller through the recording sheet at the time of sweeping the recording sheet are in contact with each other. Since it is configured to be slightly lower than the plane of the bed, when the recording paper is swept out by being sandwiched in the gap between the rubber roller and the member such as the wheel, the force for pulling the recording paper below the plane of the bed. As a result, the recording sheet is prevented from being lifted up, and the recording sheet can be fed in close contact with the bed surface.

[Brief description of drawings]

FIG. 1 is a schematic plan view of a main part of an inkjet printer to which a sheet floating prevention mechanism according to the present invention is applied.

FIG. 2 is a schematic side view of a main part of an inkjet printer to which a paper floating prevention mechanism 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 an external perspective view showing a more detailed configuration example in the vicinity of a wheel that cooperates with the sweep-out side rubber roller.

FIG. 5 is an external perspective view of a printer housing integrally formed by injection molding.

FIG. 6 is a diagram illustrating the configuration of a conventional inkjet printer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Printer housing 2 ... Paper pressing leaf spring 5 ... Round bar for forming fulcrum of paper pressing leaf spring 6 ... Carriage guide shaft 7 ... Sweep side rubber roller 8 ... Shaft 9 ... Wheel 10 ... Leaf spring 11 ... Carriage 101 ... Bed 110 ... Wheel bearing member 110a ... Arm 110b ... U-shaped groove P ... Recording paper

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location B65H 29/20

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 a feeding direction of the recording paper. In an inkjet printer for recording on the above, a position where a rubber roller for sweeping out a recording sheet that has run on the flat surface of the bed and a member such as a wheel that is pressed against the rubber roller through the recording sheet at the time of sweeping the recording sheet is in contact with A paper floating prevention mechanism for an ink jet printer, which is slightly lower than the plane of the bed.