KR102023982B1 - Paper feeding apparatus for printer - Google Patents

Abstract

The present invention relates to a paper feeder for a printer, and more particularly, to a paper feeder for a printer that can alleviate the impact when the rear end of the paper is out of the circumferential surface of the pickup roller to contact the bottom surface of the paper stack.
The paper feeding device of the printer according to the present invention comprises a paper stacking unit for stacking at least one sheet of paper; A pickup roller provided to protrude from a bottom surface of the paper stacking portion, and feeding the paper forward; Pressing means for pressing the paper downward to closely contact the pickup roller; And a buffer protruding linearly from the bottom surface of the paper stacking portion to mitigate an impact when the rear end of the paper is out of the circumferential surface of the pickup roller and in contact with the bottom surface of the paper stacking portion.

Description

Printer Feeder {PAPER FEEDING APPARATUS FOR PRINTER}

The present invention relates to a paper feeder for a printer, and more particularly, to a paper feeder for a printer that can alleviate the impact when the rear end of the paper is out of the circumferential surface of the pickup roller to contact the bottom surface of the paper stack.

The performance of cameras mounted on smart devices such as smartphones is approaching that of general digital cameras, and the population that captures memories by taking pictures with smart devices that are always easier to carry than digital cameras is increasing. As a result, consumers' desire to take photographs and print them immediately without any conversion is growing.

Reflecting such demands from consumers, photo printer products that can print pictures in a smartphone anytime and anywhere have been disclosed.

Although there are many types of such photo printers, there is disclosed a photo printer in which a printing paper employing a zero ink method is applied, so that no additional ink or a cartridge is required and thus a maintenance cost is low. Here, the zero ink method refers to a method in which a color corresponding to a cartridge is included in the paper to express colors using only heat. In other words, dyes expressing color in response to heat are stacked on paper to print an image (photo) or text by controlling the heating temperature or heating time of the head.

1 and 2 show a conventional zero-ink portable photo printer. As shown, the conventional printer 100 includes a base 110, a pickup roller R1, a platen roller R2, a thermal head 140, a mounting portion 151, and a pressing means 160. .

The base 110 has a paper stacking unit 111 formed by stacking a plurality of sheets of paper, and a frame 115 extending to the front side is coupled to a lower portion of the base 110. Forming and combining the frame 115 separately is for ease of manufacture and may be formed integrally.

The pickup roller R1 protrudes from the bottom surface of the paper stacking part 111 of the base 110 and supplies the paper located at the lowermost part of the stacked paper to the front.

On the other hand, there is provided a paper pressing member 120 for elastically pressing the paper laminated on the paper loading portion 111, the paper pressing member 120 is coupled to the upper surface of the side wall of the base 110 It is provided to be inclined downward toward the pickup roller R1 to press the paper downward. As such, when the paper is pressed, the friction force between the paper and the pickup roller R1 increases, and when the pickup roller R1 rotates, the paper positioned at the bottom of the paper is smoothly fed forward.

Platen roller (R2) is a component for discharging the paper supplied by the pickup roller (R1) to the front, the rotating shaft is coupled to the frame (115).

The upper portion of the platen roller R2 and the lower portion of the mounting portion 151 is provided with a thermal head 140, the thermal head 140 by applying heat of a predetermined temperature to the paper to express a color corresponding to the temperature To print an image or text.

It also includes a PCB for controlling the heating temperature or heating time of the thermal head 140.

In addition, when the paper enters between the thermal head 140 and the platen roller R2, the rear side of the mounting portion 151 may extend the base (the base) so that the gap between the head 140 and the platen roller R2 is extended. A hinge hole is formed as a coupling part coupled to the pivot shaft 113 formed on the side wall of the 110.

In addition, the thermal head 140 is in close contact with the paper transfer heat, in this way is provided with a pressing means 160 for pressing the thermal head 140 downward in order to adhere the thermal head 140 to the paper.

3 shows a paper feeding process of a conventional porter printer. (a) shows a state in which a plurality of sheets are stacked in the paper stacking portion. As shown, the upper portion of the sheet is pressurized by the sheet pressing member 120, which causes the sheet P1 located at the bottom to be 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 loaded paper, that is, in contact with the pickup roller R1, is fed forward by the rotation of the pickup roller R1. (See (b)).

In this way, the rear end of the paper is fed by friction with the circumferential surface of the pickup roller R1, and then falls to the bottom surface of the paper loading part while being spaced apart from the circumferential surface of the pickup roller at the point where the projection of the pickup roller ends (see (c)). ).

However, when the rear end of the paper is in close contact with the circumferential surface of the pickup roller, the paper is gently lowered along the circumferential surface. This will change the paper feed speed.

This phenomenon also affects the front end of the paper. That is, when an impact occurs while the rear end of the paper is in contact with the bottom surface, the front end of the paper being imaged due to engagement between the platen roller R2 and the thermal head 140 is shaken. It is natural that the part forming the image by being engaged between the platen roller R2 and the thermal head 140 should be firmly fixed without any movement to print with high quality. Therefore, when the front end (printed part) of the paper shakes, print quality such as streaks in the direction in contact with the thermal head is degraded. This phenomenon is called a hand-off phenomenon.

As shown in FIG. 4, a predetermined gap is formed between the platen roller R2 and the thermal head 140, and the gap is smaller than the thickness of the paper. The head is elastically pressed downwards, but the structure is controlled so as not to lower any more below a predetermined position so that the gap is formed. Usually, the gap d1 is about 0.1 mm, and the paper thickness d2 is 0.28 mm.

In this state, the paper enters the gap between the platen roller R2 and the thermal head 140 and the head is raised.

Patent Publication No. 10-2017-0082404

The present invention has been made to solve the above problems, an object of the present invention is to lower the one side of the pickup roller when the paper enters between the platen roller and the head so that the rear end of the paper is off the circumferential surface of the pickup roller, the bottom of the paper stacking unit. An object of the present invention is to provide a printer feeding device that can alleviate the impact of contact with a surface.

In order to solve the above technical problem, the paper feeding device of the printer according to the present invention frame; A paper loading part provided in the frame and on which paper is loaded; A pressing unit which presses the paper stacked in the paper loading section downward; A pickup roller which protrudes from the bottom surface of the paper stacking portion and supplies the paper stored forward; A platen roller coupled to the frame to discharge paper fed by the pickup roller forward; A head which is positioned in a state where a predetermined gap is formed in an upper portion of the platen roller, and includes a heat generating unit to apply heat to the paper; Pressing means for elastically pressing the head downward; And an inner side of the frame, one end of which is coupled to the head, and an end of which is formed a shaft hole through which the shaft of the pickup roller passes, and is fixed to the inside of the frame between the coupling part and the shaft hole. It includes a; lever is formed a fixed portion.

In addition, it is preferable that a gap is formed between the head and the platen roller smaller than the thickness of the paper, and the head moves upward when the paper enters the gap.

In addition, as the head moves upward, the lever swings about the fixed part, and the shaft hole is preferably lowered.

In addition, the shaft of the pickup roller is preferably lowered while swinging in the shaft hole.

In addition, the lever is provided with a through hole through which the shaft of the reduction gear penetrates, and the pickup gear coupled to the shaft of the pickup roller is preferably lowered while turning along the outer circumferential surface of the reduction gear mounted to the through hole.

In addition, it is preferable that a long hole is formed at one side of the paper loading part so that one side of the pickup roller can descend.

According to the present invention, when the paper enters between the platen roller and the head, one side of the pickup roller is lowered.

This can alleviate the impact when the rear end of the paper comes out of the circumferential surface of the pickup roller and contacts the bottom surface of the paper stacking portion.

By mitigating such an impact, print quality can be improved by minimizing adverse effects such as streaks on images.

1 and 2 show the structure of a conventional portable printer.
3 and 4 show a feeding state of a conventional portable printer.
5 to 9 show the structure of an embodiment according to the present invention.
10 to 14 show the operating state of the embodiment shown in FIG.

Hereinafter, with reference to the accompanying drawings will be described in detail the configuration and operation of the embodiment according to the present invention.

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

The paper loading portion 20 is provided between both sidewalls of the frame 10 and is a component on which paper is loaded.

The pickup roller R1 has a shaft installed through the paper stacking portion 20, and an upper portion thereof protrudes from the bottom surface of the paper stacking portion 20 to supply the lowermost sheet of paper loaded forward. do. The pickup gear to which the driving force is transmitted is coupled to the shaft of the pickup roller. The driving force of the motor (not shown) is transmitted to the pickup gear 71 through the reduction gears 72, and the pickup roller R1 is driven by the rotation of the pickup gear 71.

In order to smoothly feed the paper, the pickup roller R1 must have a constant friction force. For this purpose, in this embodiment, a pressure part (not shown) which elastically presses the paper loaded in the paper loading part 20 from above. ) Is provided.

The platen roller R2 is coupled to the frame 10 to discharge the paper supplied by the pickup roller R1 to the front.

The upper portion of the platen roller (R2) is provided with a head 30 including a heating unit, the head 30 is fixed to the head plate (40).

Both ends of the head plate 40 have hinge holes 41 formed therein, and are rotatably coupled to the frame 10 by hinge pins h1. In addition, the head 30 has a constant gap formed between the platen roller R2. The gap is formed smaller than the thickness of the paper.

In addition, a pressing means for elastically pressing the head 30 downward is provided. In this embodiment, the pressing means is located on the top of the head 30, one end is composed of a pressing plate 50 is formed with a hinge hole 51 to be hinged rotatably to the frame 10. The pressure plate 50 is connected to the other end of the spring, the other end of the spring is connected to the frame. Therefore, the head 30 is always elastically loaded downward by the pressing plate 50.

In addition, in this embodiment, when the paper enters the gap between the head 30 and the platen roller R2, one end of the pickup roller R1 descends as shown in FIG. To this end, the lever 60 is provided inside the side wall of the frame 10. The lever 60 is fixed to the fixing point 12 of the frame.

Referring to FIG. 9, the lever 60 has a fixing portion 61 fixed to the fixing point 12 of the frame 10, and one side of the fixing portion 61 has the head 30. A coupling portion 62 to be coupled is formed, and on the other side, a shaft hole 63 through which the shaft of the pickup roller R1 passes is formed.

In this embodiment, the fixing screw penetrates the coupling part 62 to fix the lever 60 and the head 30.

The shaft hole 63 passes through the shaft of the pickup roller R1, and the pickup gear 71 is coupled to the end of the shaft. However, the shaft hole 63 is formed in a long hole so that the pickup gear can move. This will be described later.

Hereinafter, with reference to Figures 10 and 11 will be described the operating state of the embodiment according to the present invention.

First, FIG. 10 shows a state before the sheet enters the gap between the platen roller R2 and the head 30. In this state, the axis of the pick-up roller R1 is positioned in parallel and protrudes in parallel to the paper stacking portion 20. In addition, the shaft S1 of the pickup roller R1 is located above the shaft hole 63 (see (a) of FIG. 10).

FIG. 11 shows a state where the paper has entered 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.

At this time, the coupling portion 62 of the lever 60 is also raised because it is coupled to the head 30, the other side relative to the fixing portion 61 by the lever principle is rather lowered.

Therefore, the shaft hole 63 formed on the other side of the lever is to descend. At the same time, one side of the pickup gear 71 and the pickup roller R1 fitted to the shaft hole 63 is lowered. Since the pickup gear 71 is engaged with the neighboring reduction gear 72, even if the shaft hole 63 is lowered, the pickup gear 71 does not vertically fall, and turns over the reduction gear 72. Descending.

Referring to Figure 12, (a) shows the position of the pickup gear before the paper enters the gap between the platen roller (R2) and the head 30, (b) the paper is platen roller (R2) And the position of the pickup gear when entering the gap between the head 30.

For reference, the reduction 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 small circumferential surface among the reduction gears.

When the paper enters the gap between the platen roller R2 and the head 30, the lever hole descends by the lever principle, and the pickup gear 71 inserted in the shaft hole 63 It descends while turning along the circumferential surface of the second gear 72a of the reduction gear (see arrow).

Therefore, the shaft hole 63 of the lever 60 is formed in the form of a long hole to provide a copper wire of the pickup gear 71 that pivots and moves.

FIG. 13A shows a state where the shaft S1 of the pickup roller passes through the shaft hole 63 before the paper enters the gap, and the paper is the gap between the platen roller R2 and the head 30. After entering the shaft (S1) of the pick-up roller is shown in the down state in the shaft hole (63).

When one side of the pick-up roller R1 descends as described above, the impact when the rear end of the paper comes out of the circumferential surface of the pick-up roller R1 can be alleviated and the impact of contacting the bottom surface of the paper stacking portion 20 can be alleviated. . Therefore, the paper feeding speed at this time is rapidly increased, thereby preventing the handoff phenomenon that degrades the print quality.

Referring to FIG. 14, in order for one side of the pickup roller to descend by the lever operation of the lever 60, the long hole 22 must be formed on the side wall of the paper loading part 20. Since the shaft S1 of the pick-up roller is not vertically lowered but descends with a constant curve, the long hole 22 of the paper loading part is also formed in a uniformly inclined shape.

1: Example
10: frame
20: paper loading part
30: head
40: head plate
50: pressing plate
60: lever

Claims (6)

frame;
A paper loading part provided in the frame and on which paper is loaded;
A pressing unit which presses the paper stacked in the paper loading section downward;
A pickup roller protruding from the bottom surface of the paper loading 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 rotatably coupled to one side of the frame and lowering one side of the pickup roller when the head is raised.
The method of claim 1,
The lever is
One side is coupled to the head, the other side of the printer paper feeder, characterized in that the shaft hole through which the shaft of the pickup roller is formed.
The method of claim 2,
A gap formed between the head and the platen roller is smaller than the thickness of the paper, and the head moves upward when the paper enters the gap.
The method of claim 2,
The shaft hole is a printer paper feeder, characterized in that formed in the long hole.
The method of claim 1,
A pickup gear is coupled to the shaft of the pickup roller, and one side of the frame is provided with a reduction gear engaged with the pickup gear.
The printer feeder, characterized in that when the one side of the pickup roller is lowered, the pickup gear is lowered while turning along the outer peripheral surface of the reduction gear.
The method of claim 1,
Printer feeder, characterized in that the long hole is formed on one side of the paper loading portion.

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