JPH0569987A - Paper feeding apparatus - Google Patents

Abstract

PURPOSE:To mount a paper stock sensor in a paper feeder apparatus such as a printer, which enables the reduction in size of the mounting space and the accompanying reduction in cost and simultaneously enables detecting a stocked state of paper with high precision. CONSTITUTION:A paper feed roller 1 is disposed above a paper feed tray 4 while a paper raising roller 2 is disposed under the same. Paper feeding is effected by pressing a developing paper 5 stocked in the paper feed roller 4 against the rotating paper feed roller 1 by the paper raising roller 2. A reflective sensor 6 is disposed between frame portions 2a formed in a paper abutment surface of the paper raising roller 2, thereby miniaturizing the mounting space therefor. Detection of that the paper stock is present or absent is made with the developing paper 5 being pressed against the paper feed roller 1. Namely, the detection precision is enhanced with the detection distance being kept constant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeding device having an improved method of mounting a paper stock sensor in a printer or the like.

[0002]

2. Description of the Related Art FIG. 5 shows a conventional method of mounting a paper stock sensor in a paper feeder. Reference numeral 101 denotes a paper feed tray in which a plurality of printing papers 102 are stocked, for example. Paper tray 101 is for stocked paper 102.
The paper feed roller 103 has a structure capable of coming into contact with the lower surface of the paper feed roller 103, and a base 104 is provided above the paper feed tray 101.

Here, when the paper is fed, the paper feed roller 103 is pushed up to stock the photographic paper 102 in stock.
The whole is sandwiched by the paper feed roller 103 and the base 104 with an appropriate pressure contact force. When the paper feed roller 103 is rotated in this state, the lowermost printing paper 102 is fed forward by a frictional force with the paper feed roller 103.

Such a sheet feeding device is used in a printer or the like, and normally, when performing a printing operation, it is performed after confirming that the sheets are stocked. Therefore, a paper stock sensor 105 is provided in the paper feeding device. The conventional paper stock sensor 105 includes a light emitting unit 105a and a light receiving unit 1.
A transmissive sensor including a light-receiving part 105b is provided above the paper feed tray 101.
Is attached below the paper feed tray 101, and if there is at least one photographic printing paper 102 between them, transmitted light is blocked and stock is detected, and if there is no photographic paper 102, light is detected to detect no stock.

[0005]

However, in the above-mentioned conventional method of mounting the paper stock sensor,
(1) Since it is used as a transmissive type, the mounting space becomes large. (2) It is difficult to obtain accuracy because the distance is long. (3) Similarly, the workability is poor because the distance is large.
(4) The cost is high. There was such a problem.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a paper stock sensor capable of reducing the mounting space, accurately detecting the stock status of paper, and reducing the cost. An object of the present invention is to provide a paper feeding device that realizes attachment.

[0007]

In order to achieve the above object, in the paper feeding device of the present invention, the stocked paper is sandwiched by the relative pressure contact force between the paper feeding roller and the paper contact member,
A paper feeding device that feeds paper by rotating the paper feeding roller, wherein an edge or a recess is formed on the paper contact surface of the paper contact member, and the stocked paper is placed between the edges or in the recess. It is characterized in that a reflection type sensor for detecting is arranged.

[0008]

In the paper feeding device of the present invention, a sensor for confirming the stock of the paper is also used as the paper contact member, so that the distance between the paper and the sensor is made constant, and the reflection type sensor can be used. And improve the installation space and workability.

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a schematic configuration diagram of a first embodiment of the present invention. In this embodiment, the case where it is applied to a full-color printer is taken as an example. As a constituent of the paper feeding device of the present embodiment, 1 is a paper feeding roller, 2 is a paper pushing up arm, 2a is a frame portion, 3 is a drive shaft of the paper pushing up roller 2, 4 is a paper feeding tray, and 5 is photographic paper. , 6 are reflection type sensors for checking the paper stock.

Further, as a printing mechanism of the full-color printer, 11 is a platen, 12 is a ribbon cartridge, 13 is an ink ribbon, 14 is a thermal head, 15 is an auxiliary roller, 16 is a discharge switching roller, 17,
Reference numeral 18 is a guide.

Reference numeral 21 denotes a video circuit, which constitutes a circuit section for controlling the mechanical section of the above-mentioned full-color printer.
21a is a video input terminal, 22 is an A / D converter, 2
3 is a memory circuit, 24 is a CPU (processor), 25 is a printed circuit, 26 is a mechanical deck control circuit, 2
7 is a paper feed roller 1, a paper pushing arm 2, a platen 1
1, one or a plurality of motors for driving the ribbon cartridge 12 and the like.

First, the structure of the sheet feeding device, which is the main part of this embodiment, will be described. The paper feed tray 4 has a depth capable of stocking a plurality of printing papers 5, a paper feed roller 1 is arranged above it, and a paper push-up arm 2 is arranged below it. One end of the paper push-up arm 2 is rotatable around the drive shaft 3 as a fulcrum, and the other end thereof is brought into contact with the lower portion of the photographic paper 5 stocked in the paper feed tray 4 and can be pushed up. There is.

In this embodiment, the paper push-up arm 2 also serves as a mounting member for the reflection type sensor 6 which is a paper stock confirmation sensor. That is, as shown in detail in FIG. 2, a frame portion 2a is formed on the paper contact surface of the paper push-up arm 2, and the reflection type sensor 6 is attached between them. in this case,
The tip of the frame portion 2a comes into contact with the paper, and the height of the frame portion 2a is such that when the reflective sensor 6 is attached, the dimension H between the paper contact surface and the reflective sensor 6 is equal to the reflection distance of the sensor. To be set. The frame portion 2a may be an edge portion that surrounds the entire circumference of the sheet contact surface, or an edge portion provided on two sides or the like.

Next, returning to FIG. 1, the structure of the printing mechanism and its operation will be described. The ribbon cartridge 12 includes an ink ribbon 13 rotatably wound around a supply reel 12a.
Is integrally formed on the take-up reel 12b so as to be wound up. Such a ribbon cartridge 12 is arranged at a position where the exposed portion of the ink ribbon 13 can come into contact with the platen 11, and the thermal head 1 is provided on the platen 11 and the reflection side.
4 is arranged so that the ink ribbon 13 can be pressed against the platen 11. Printing paper 5 fed from the above-mentioned paper feed tray 4
Is inserted between the platen 11 and the ink ribbon 13,
The dye of the ink ribbon 13 is transferred in contact with the thermal head 14 according to the amount of heat generated by energization. Transfer is performed three times, Y (yellow), M (magenta), and C (cyan). At the time of printing these, in order to prevent the paper from coming off the platen 11, it is pressed by the auxiliary roller 15 and the discharge mode switching roller 16. The same applies to the guides 17 and 18. When printing is completed, the paper discharge switching roller 16 is removed from the platen 11, and the printing paper 5 is discharged.

Next, the structure and operation of the circuit section will be described.
The video image is input from the video input terminal 11 a, passes through the video circuit 21, is converted into a digital signal by the A / D converter 22, and is captured in the memory circuit 23.
Next, the mechanical deck control circuit 2 for printing
6, the paper feed roller 1 is controlled by the motor 27, and the printing paper 5 is sent to the platen 11. Next, the image stored in the memory circuit 23 is sent to the printed circuit 25, a signal current is passed through the thermal head 14, and the above-mentioned printing is performed. The control of the printing mechanism at the time of printing and discharging the paper is also performed via the mechanical deck 26 and the motor 27. The CPU 24 commands the timing of control of each of the above circuit parts. The detection output of the reflection type sensor 6 for checking the paper stock is the CPU 24.
Connected to.

In the printer constructed as described above, the operation of the sheet feeding device which is the main part of this embodiment will be described.

First, the paper feeding method is as follows. The paper feed roller 1 is rotated in the direction A, and then the paper pushing arm 2 presses the entire photographic paper 5 stocked in the paper feed tray 4 against the paper feed roller 1 with an appropriate pressing force.
As a result, the topmost photographic printing paper 5 is replaced by the paper feed roller 1.
It is sent out from the paper feed tray 4 by friction with. At this time,
The presence or absence of paper stock is checked when the photographic paper 5 is pressed against the paper feed roller 1 by the paper push-up arm 2 as shown in FIG. Therefore, the distance between the photographic printing paper 5 and the reflective sensor 6 can be kept constant, and the detection can be performed stably and accurately.

In the above, when it is detected that there is no paper stock, the CPU 24 stops the paper feeding operation and stops the next printing operation. As a result, so-called color hitting is prevented, and accidents such as ink adhesion to the thermal head 14 and fusing of the ink ribbon 13 can be prevented.

If there is no paper stock in the above case, the paper push-up arm 2 is pressed against the paper feed roller 1 that rotates until the paper stock is detected. Therefore, the paper feed roller 1 is provided with a torque limiter. It is suitable. In addition, the paper feed roller 1 is not rotated until the presence or absence of paper stock is detected by a command from the CPU 24, and after the paper stock is detected, the paper feed roller 1 is rotated to perform paper feeding. good.

Next, a second embodiment of the present invention will be described. Figure 4
FIG. 3 is a diagram showing its configuration. Here, only the sheet feeding device is shown. In the figure, 1 is a paper feed roller, 2 is a paper push-up arm, 3 is a drive shaft, 4 is a paper feed tray, 5 is photographic paper, 6 is a reflective sensor, 7 is a base, and 7a is a recess.

In the structure of this embodiment, the paper feed roller 1 is arranged below the die feed tray 4, and the paper feed roller 1 is connected to the drive shaft 3.
Is rotatably attached to the tip of the paper pushing-up arm 2 which rotates about the fulcrum. The base portion 7 is arranged above the paper feed tray 4, and when the paper feed roller 1 pushes up the entire photographic paper 5 by the paper pushing arm 2, the upper surface of the photographic paper 5 is brought into contact. The reflective sensor 6 has a recess 7 a formed in the base 7.
Is located in. The depth dimension of the recess 7a is the same as in FIG.

In the above structure, the presence or absence of paper stock is detected while the paper feeding roller 1 presses the entire printing paper 5 against the base 7. Therefore, as in the first embodiment, the distance between the reflection type sensor 6 and the photographic printing paper 5 becomes constant, and the detection can be performed stably and accurately. Paper is fed by rotating the paper feed roller 1 and friction with the lowermost printing paper 5.

As described above, the present invention can be applied in various ways in accordance with the gist thereof and can take various embodiments.

[0025]

As is apparent from the above description, according to the paper feeding device of the present invention, since the reflection type sensor for checking the paper stock is also attached while also functioning as the paper contact member, the mounting space is reduced. Is smaller, workability is improved, and cost can be reduced. Further, since the reflection type sensor is used, the detection can be performed by contacting the sheet, the variation of the distance, which is a drawback of the reflection type, is improved, and stable and accurate detection can be performed.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a mounting view of the reflection type sensor in the above embodiment.

FIG. 3 is a diagram showing an operation state of a paper feed roller and a paper push-up arm in the above embodiment.

FIG. 4 is a configuration diagram showing a second embodiment of the present invention.

FIG. 5 is a diagram showing a conventional method of attaching a paper stock sensor.

[Explanation of symbols]

1 ... Paper feeding roller, 2 ... Paper pushing arm, 2a ... Frame part,
3 ... Drive shaft, 4 ... Paper feed tray, 5 ... Printing paper, 6 ... Reflective sensor, 7 ... Stand portion, 7a ... Recessed portion.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Hideki Ito 6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation (72) Inventor Shin Iima 6-7-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Inside Sony Corporation (72) Inventor Mutsuko Narita 6-735 Kitashinagawa, Shinagawa-ku, Tokyo Inside Sony Corporation

Claims (1)

[Claims] 1. A sheet feeding device for sandwiching a stocked sheet by a relative pressure contact force between a sheet feeding roller and a sheet contact member, and feeding the sheet by rotating the sheet feeding roller. An edge portion or a concave portion is formed on the sheet contact surface of the sheet feeding device, and a reflection type sensor for detecting the stocked sheet is disposed between the edge portions or the concave portion.