WO2019132499A1

WO2019132499A1 - Paper feeder for printer

Info

Publication number: WO2019132499A1
Application number: PCT/KR2018/016636
Authority: WO
Inventors: 윤희필; 정구범
Original assignee: 디에스글로벌 (주)
Priority date: 2017-12-26
Filing date: 2018-12-26
Publication date: 2019-07-04
Also published as: KR102023982B1; KR20190077768A

Abstract

The present invention relates to a paper feeder for a printer and, more particularly, to a paper feeder for a printer, which can reduce an impact occurring when the rear end of a sheet of paper leaves the circumferential surface of a pickup roller and comes into contact with the bottom surface of a paper storage unit. The paper feeder for a printer according to the present invention comprises: a frame; a paper storage unit which is disposed in the frame and in which paper is stored; a pressing unit for pressing the paper stored in the paper storage unit in the downward direction; a pickup roller protruding from the bottom surface of the paper storage unit; a platen roller coupled to the frame; a head disposed above the platen roller; a spring for pressing the head downward; and a lever for lowering one side of the pickup roller when the head is raised.

Description

Printer feeder

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a paper feeding device for a printer, and more particularly, to a paper feeding device for a printer capable of mitigating an impact when a rear end of a paper leaves a circumferential surface of a pickup roller,

The performance of cameras mounted on smart devices such as smart phones is close to that of ordinary digital cameras, and the number of people who take memories by taking pictures with smart devices that are always easy to carry rather than digital cameras is increasing. As a result, there is a growing demand from consumers who want to take pictures and output them immediately without any conversion.

As a result of these demands, a photo printer product has been launched that enables users to print photos in a smart phone anywhere, anytime.

There are various types of such photo printers, but in particular, there is disclosed a photo printer in which a printing paper employing a zero ink method is applied, and ink and a cartridge are not additionally required, and the maintenance cost is reduced. Here, the zero ink system is a system in which images (photographs) or texts are printed by controlling the heat temperature or the heat generation time of the head, in which dyes sensitive to heat and exhibiting color are stacked on the paper.

Figs. 1 and 2 show a conventional portable photo printer of the ink type. The conventional printer 100 includes a base 110, a pickup roller R1 and a platen roller R2, a thermal head 140, a mounting portion 151 and a pressing means 160 .

The base 110 is formed with a paper receiving portion 111 in which a plurality of sheets of paper are stacked and housed. A frame 115 is coupled to both sides of the base 110, (115) may be separately formed and joined to facilitate fabrication, or may be integrally formed.

The pickup roller R1 protrudes from the bottom surface of the paper storage part 111 of the base 110 and feeds the paper positioned at the lowermost part of the stacked paper sheets forward.

The pressing unit 120 is coupled to the upper surface of the side wall of the base 110 and includes a pressing roller 120 and a pressing roller 120. The pressing roller 120 presses the paper, (R1), and presses the paper downward. When the paper is pressed, the frictional force between the paper and the pick-up roller R1 becomes large, so that the pick-up roller R1 does not slip and the paper positioned at the bottom of the paper is smoothly fed forward.

The platen roller R2 is a component for forwardly discharging the paper supplied by the pick-up roller R1, and both axes are coupled to the frame 115. Fig.

A thermal head 140 is provided on the upper portion of the platen roller R2 and below the mounting portion 151 and includes a PCB for controlling the heating temperature or the heating time of the thermal head 140. [

The rear side of the mounting portion 151 is extended from the base 110 so that the gap between the head 140 and the platen roller R2 is expanded when the sheet enters between the thermal head 140 and the platen roller R2. A hinge hole is formed as a coupling portion to be coupled to the hinge shaft 113 formed on the side wall of the hinge shaft.

The thermal head 140 closely contacts the paper and transfers heat. The pressing unit 160 presses the thermal head 140 downward to closely contact the thermal head 140 with the paper. The pressing means 160 is provided on the upper portion of the mounting portion 151 and is hinged to the hinge shaft 113 like the mounting portion 151. The thermal head 140 and the platen roller R2 are elastically brought into close contact with each other by a spring S connected to one side of the pressing means 160 and the engaging portion 115a of the frame. A stopper 114 is formed on one side of the frame to form a gap between the thermal head 140 and the platen roller R2.

3 illustrates a paper feed process of a conventional porter printer. (a) shows a state in which a plurality of sheets of paper are stacked on the sheet storage portion. As shown in the figure, the upper portion of the sheet is pressed by the pressing portion 120, so that the sheet P1 located at the lowest position is in close contact with the pickup roller R1.

When the pickup roller R1 rotates in this state, the paper P1 at the bottom of the stacked sheets, that is, the paper P1 in contact with the pickup roller R1 is fed forward by the rotation of the pickup roller R1 (See (b)).

The rear end of the sheet is fed by friction with the circumferential surface of the pickup roller R1, and is separated from the circumferential surface of the pickup roller at the end of the protruding portion of the pickup roller, Reference).

However, when the rear end of the sheet is closely contacted with the circumferential surface of the pickup roller and is fed, the sheet is gradually lowered along the circumferential surface. When the sheet is released from the circumferential surface, the impact is transmitted to the rear end of the sheet by the pressing force of the pressing portion 120, The paper feeding speed is changed.

This phenomenon also affects the shearing of the paper. That is, when the rear end of the paper contacts the bottom surface and an impact is generated, the front end of the paper under image formation is shaken due to engagement between the platen roller R2 and the thermal head 140. [ It is a matter of course that the portion where the image is formed by the engagement between the platen roller R2 and the thermal head 140 must be firmly fixed without movement to be printed with high quality. Therefore, if the sheet is shaken at the front end (printed portion) of the sheet, the printing quality such as the occurrence of stripes in the direction in contact with the thermal head is lowered. This phenomenon is referred to as a hand-off phenomenon.

As shown in FIG. 4, a gap is formed between the platen roller R2 and the thermal head 140, and the clearance is smaller than the thickness of the paper. The thermal head is resiliently pressed downward, but the gap is formed by the stopper 114. Usually, the gap d1 is about 0.1 mm, and the thickness d2 of the paper is 0.28 mm.

In this state, the paper enters the gap between the platen roller R2 and the thermal head 140, and the thermal head 140 rises as the mounting unit 151 and the pressing unit 161 swing.

SUMMARY OF THE INVENTION The present invention has been conceived to solve the problems described above, and it is an object of the present invention to provide a paper feeding device, in which a paper is lowered on one side of a pickup roller when entering between a platen roller and a head, And it is an object of the present invention to provide a paper feeding device of a printer which can mitigate an impact when it comes into contact with a floor surface.

According to an aspect of the present invention, there is provided a printer feeder comprising: a frame; A paper accommodating unit provided in the frame and storing paper therein; A pressing unit that presses the paper stored in the paper storage unit downward; A pickup roller protruding from a bottom surface of the paper receiving portion; A platen roller coupled to the frame; A head positioned above the platen roller; A spring for urging the head downward; And a lever for lowering one side of the pickup roller when the head rises.

It is also preferable that the lever is rotatably coupled to one side of the frame, one side is coupled with the head, and the other side is formed with a shaft hole through which the shaft of the pickup roller passes.

Further, it is preferable that the shaft hole is formed as a long hole.

Further, it is preferable that a guide hole is formed at one side of the paper storage unit so that one side of the pickup roller can descend.

The pickup gear is coupled to a shaft of the pick-up roller. At least one transmission gear is engaged with the pick-up gear at one side of the frame. The pick-up gear rotates along an outer peripheral surface of the transmission gear desirable.

According to the present invention, when the sheet moves between the platen roller and the head, one side of the pickup roller is lowered. This makes it possible to mitigate the impact when the rear end of the sheet leaves the circumferential surface of the pickup roller and contacts the bottom surface of the sheet storage portion.

By mitigating such an impact, it is possible to minimize adverse effects such as a hand-off phenomenon in which stripes are generated in the image, thereby improving the print quality.

1 and 2 show a structure of a conventional portable printer.

FIGS. 3 and 4 illustrate feeding states of a conventional portable printer.

5 to 9 show the structure of an embodiment according to the present invention.

FIGS. 10 to 14 show the operating states of the embodiment shown in FIG.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a configuration and an operation of an embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

5 to 8, an embodiment (1) according to the present invention includes a frame 10, a paper storage section 20, a pickup roller R1, a platen roller R2, a head 30, a pressing means and a lever 60.

The paper accommodating portion 20 is provided between both side walls of the frame 10 and is a component in which a plurality of paper sheets are stacked up and down. The paper usually has a rectangular shape.

The pickup roller R1 has two axes passing through the paper accommodating portion 20. The upper portion of the pickup roller R1 protrudes from the bottom surface of the paper accommodating portion 20 and feeds the paper, do. A pick-up gear to which driving force is transmitted is coupled to the shaft of the pick-up roller. The driving force of the motor (not shown) is transmitted to the pickup gear 71 through the transmission gears 72, and the pickup roller R 1 is driven by the rotation of the pickup gear 71.

In order to smoothly supply the paper, the pick-up roller R1 must have a constant frictional force so as not to slip. To this end, in the present embodiment, the pressing roller (R1) presses the paper stacked on the paper- (Not shown). The pressing portion may have the same structure as the pressing portion 120 of FIG.

The platen roller R2 is coupled to the frame 10 by two shafts and discharges the paper fed by the pickup roller R1 forward.

Above the platen roller R2, a head 30 including a heating part is provided, and the head 30 is coupled to the bottom of the head plate 40. [

A hinge hole 41 is formed on both sides of the head plate 40 and is rotatably coupled to the frame 10 or the paper accommodating portion 20 by a hinge pin h1. Further, the head 30 has a certain gap formed between the head 30 and the platen roller R2. The gap is formed to be smaller than the thickness of the paper.

And a pressing means for resiliently pressing the head 30 downward is provided. In this embodiment, the pressing means is located on the upper side of the head 30 and includes a pressing plate 50 having a hinge hole 51 formed at one end thereof so as to be rotatably hinged to the frame 10. A spring is connected to the other end of the pressing plate 50, and the other end of the spring is connected to the frame 10. Therefore, the head 30 is always elastically underloaded by the pressing plate 50 downward. It is also possible that the spring is directly connected to the head plate 40 or the head 30 without being connected to the pressing plate 50.

8, when one end of the pick-up roller R1 is in contact with the platen roller R2 as shown in Fig. 8, when the head 30 is lifted up, It is a descending structure. To this end, a lever 60 is provided inside the one side wall of the frame 10. The lever 60 is a component for lowering one side of the pick-up roller when the head rises.

The lever is fixed to a fixed point 12 of the frame but is rotatable with respect to the fixed point 12. The lever is fixed to the fixing point 12 by a rivet, a fixing pin, a screw or the like.

9, the lever 60 is formed with a fixing portion 61 fixed to the fixing point 12 of the frame 10, and the fixing portion 61 is formed on one side of the fixing portion 61, And a shaft hole 63 through which the shaft of the pickup roller R1 passes is formed on the other side.

In this embodiment, the fixing screw passes through the engaging portion 62 to fix the head 30 to one side of the lever 60. [

The shaft hole 63 penetrates through the one side of the pickup roller R1 and the pickup gear 71 is coupled to the end of the shaft of the pickup roller. In particular, the shaft hole 63 is formed as a long hole having a predetermined curvature so that the axis of the pickup roller can be moved (descended) while turning. This will be described later.

Instead of forming the shaft hole 63 as a long hole, a narrow hole through which the shaft of the pickup roller passes may be formed, or an axis of the pickup roller may be coupled.

Hereinafter, an operation state of the embodiment of the present invention will be described with reference to FIGS. 10 and 11. FIG.

10 shows a state before the paper has yet entered the gap between the platen roller R2 and the head 30. As shown in Fig. In this state, the axis of the pick-up roller R1 is positioned in parallel and protrudes in parallel with the paper accommodating portion 20. The shaft S1 of the pickup roller R1 is positioned above the shaft hole 63 (see Fig. 10 (a)).

11 shows a state in which the rear end of the sheet is out of the circumferential surface of the pickup roller and is in contact with the bottom surface of the sheet storage portion.

At the same time, the front end of the sheet enters the gap between the platen roller (R2) and the head (30). Since the gap is smaller than the thickness of the sheet, when the sheet enters the gap, the head 30 is raised. That is, the head plate 40 swings upward along the hinge pin h1.

Since the head 30 is coupled to the engaging portion 62, one side of the lever 60 is also elevated due to the rise of the head 30. [

When one side of the lever 60 is raised, the other side is lowered with respect to the fixing portion 61 by the principle of the leverage.

Therefore, the shaft hole 63 formed on the other side of the lever descends. At the same time, one side of the pick-up roller (R1) fitted in the shaft hole (63) is lowered. A guide hole (22 'in FIG. 14) is formed on one side of the paper storage unit so that one side of the pickup roller can be lowered. .

Since the pick-up gear 71 is engaged with the adjacent transmission gear 72, the pick-up gear 71 is lowered while turning on the transmission gear 72 even if one side of the pick-up roller descends.

12, (a) shows the position of the pick-up gear before the sheet enters the gap between the platen roller R2 and the head 30, (b) shows the position of the sheet on the platen roller R2, And the position of the pick-up gear when entering the gap between the head 30 and the head 30.

For reference, the transmission gear 72 adjacent to the pickup gear 71 is formed of a double gear, and the pickup gear 71 is meshed with the second gear 72a having a smaller circumferential surface in the transmission gear.

When the sheet enters the gap between the platen roller R2 and the head 30, the lever 60 descends by the principle of the lever mechanism and the pickup gear 71 Descends while rotating along the circumferential surface of the second gear 72a of the adjacent reduction gear (see arrows).

Therefore, the shaft hole 63 of the lever 60 is formed in the shape of a slot having a certain curvature so that the pickup gear 71 can be rotated while maintaining engagement with the second gear 72a.

13A shows a state in which the shaft S1 of the pick-up roller passes through the shaft hole 63 before the sheet enters the gap between the head and the platen roller, and the sheet passes through the platen roller R2, And the shaft S1 of the pickup roller descends in the shaft hole 63 after entering the gap between the pickup roller 30 and the shaft hole 63. [

When the one side of the pick-up roller R1 descends in this way, the impact when the rear end of the sheet comes into contact with the bottom surface of the sheet accommodating portion 20 at the time when the rear end of the sheet leaves the circumferential surface of the pickup roller R1 can be alleviated . Therefore, the paper feeding speed at this time is rapidly increased, thereby preventing a hand-off phenomenon that deteriorates the print quality.

Referring to FIG. 14, a guide hole 22 is formed in the side wall of the paper storage portion 20 in order to lower the one side of the pickup roller by leverage of the lever 60. The shaft S1 of the pickup roller does not descend vertically but has a constant curvature and descends. Therefore, it can be seen that the guide hole 22 of the paper accommodating portion is also formed with a constant curvature.

It is possible to minimize the adverse effects such as the occurrence of streaks on the image by alleviating the impact when the rear end of the sheet leaves the circumferential surface of the pickup roller and touches the bottom surface of the sheet stacking portion, thereby improving the print quality.

Claims

frame;

A paper accommodating unit provided in the frame and storing paper therein;

A pressing unit that presses the paper stored in the paper storage unit downward;

A pickup roller protruding from a bottom surface of the paper receiving portion;

A platen roller coupled to the frame;

A head positioned above the platen roller;

A spring for urging the head downward; And

And a lever for lowering one side of the pick-up roller when the head rises.
The method according to claim 1,

The lever is rotatably coupled to one side of the frame,

And a shaft hole through which the shaft of the pickup roller passes is formed on the other side of the printer.
3. The method of claim 2,

Wherein the shaft hole is formed as a long hole.
The method according to claim 1,

And a guide hole is formed at one side of the paper receiving part so that one side of the pickup roller can be lowered.
The method according to claim 1,

A pickup gear coupled to the shaft of the pick-up roller is coupled to the pick-up roller, and at least one transmission gear is engaged with the pick-up gear at one side of the frame,

Wherein the pick-up gear is rotated downward along the outer peripheral surface of the transmission gear.