JPH0781792A - Paper feeding device - Google Patents

Abstract

PURPOSE:To prevent the generation of noise owing to collision of the rear end part of a paper sheet with a guide plate when the feed of the paper sheets is completed by providing a drive means for a guide member which is caused to make access to a paper feed port during the starting of the feed of the paper sheets and oscillated in a direction, in which the drive means is separated away from a paper feed port, when the rear end part of the paper sheet passes through the paper feed port. CONSTITUTION:Since, when a paper sheet 9 is conveyed to a cassette paper feed port 14, one end of a coupling rod 8 is lifted by a cam 11 attached on the coaxial shaft of a paper feed roller A6 in the shape of a half-moon, a force by a guide plate 10 energized upward through the force of a spring is pressed down is generated, the upper end of the guide plate 10 is lowered to a level lower than that of the cassette paper feed port 14 and the paper sheet 9 is smoothly fed. Further, when conveyance of the paper sheet 9 is progressed and the rear end of the paper sheet 9 is brought into contact with the guide plate 10, a paper discharge position 5 in a cassette 36 is positioned flush with the upper part of the guide plate 10 as a result of the guide plate 10 being energized upward, whereby the rear end of the paper sheet 9 is prevented from jumping when the rear end thereof is moved from the cassette 36 to the guide plate 10. Thus, no noise is generated.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a copying machine, a facsimile,
The present invention relates to a sheet feeding device such as a printer.

[0002]

2. Description of the Related Art FIGS. 12, 13 and 14 are cross-sectional views of a conventional apparatus. FIG. 12 shows a half-moon-shaped sheet feeding roller A49 which lowers a sheet 49 in a cassette 36 against the resistance of a spring 51. While pressing it to the cassette feed port 50
Represents the state of being transported to. In FIG. 13, the paper 49 has a paper feed roller B47 and a tension roller 45 along the guide plate 48.
The sheet detection switch 44 is turned on, and the PS plate 43 (in a copying machine, the sheet conveyance is temporarily stopped by the PS plate to synchronize the leading edge of the sheet and the photosensitive drum). The state of being sandwiched between the paper feed roller C42 and the tension roller 41 is shown. FIG. 14 shows a state in which the sheet 49 is further conveyed and the rear end of the sheet 49 is in contact with the guide plate 48.

[0003]

The cassette 36 shown in FIG.
The vertical distance B between the paper discharge position inside and the upper part of the guide plate 48 is 0.
Unless (particularly, the thicker the sheet 49 is), a sound is generated at the moment when the trailing edge of the sheet 49 hits the guide plate 48. This sound is unexpectedly unpleasant to the ear and is disadvantageous in that it makes the device quieter.
As a result, the high paper feeling of the device is impaired and the low paper feeling is increased.

[0004]

SUMMARY OF THE INVENTION The present invention has been made for the purpose of solving the above-mentioned problems, and in a paper feeding device according to claim 1, an image is processed from a paper container via a paper guide member. A sheet feeding device that feeds the sheet from the sheet storage section to a guide member,
A guide member that guides the paper in a direction different from the paper feeding direction, a supporting unit that swingably supports the guide member, and the paper that is supplied to the guide member is conveyed to the image processing unit. When the feeding roller and the feeding of the sheet are started, the sheet accommodating portion side of the guide member is brought close to the sheet feeding port (first position), and the trailing edge of the sheet passes through the sheet feeding port. In this case, there is provided a sheet feeding device comprising: the guide member drive means for swinging the side of the sheet containing portion of the guide member (the second position) away from the sheet supply port. .

According to a second aspect of the present invention, there is provided the paper feeding device according to the first aspect, wherein at least a part of the guide member is a reverse guide member that reverses and conveys a sheet by 180 degrees. .

According to a third aspect of the present invention, in the sheet feeding device, the driving means for the guide member reciprocates by receiving a sheet feeding roller, a cam coaxial with the sheet feeding roller, and slidingly contacting the cam at one end. 2. The sheet feeding device according to claim 1, further comprising a drive mechanism that operates and swings the guide member at the other end.

According to a fourth aspect of the present invention, the driving means for the guide member includes a paper detecting means for detecting the paper fed to the guide member, and the guide member at the first position or the second position. In response to a paper size signal from the paper detection signal of the paper detection means,
The sheet feeding device according to claim 1, further comprising a control unit that controls the moving unit of the guide member.

According to a fifth aspect of the present invention, in the first aspect, the driving means of the guide member detects the sheet size of the sheet storage section.
A detection unit, a second detection unit that detects the sheet fed to the guide member, a moving unit that moves the guide member to the first position or the second position, and a first detection unit. 2. The paper feeding apparatus according to claim 1, further comprising a control unit that controls the moving unit of the guide member in response to a sheet detection signal and a sheet size signal of the second detection unit.

[0009]

With the above arrangement, the height of the guide plate at the start and end of sheet feeding can be automatically changed according to the total length of the sheet. It is possible to provide a sheet feeding device that is capable of preventing the generation of a sound generated when the rear end of the sheet hits the guide plate at a time and has an excellent silent effect.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details will be described below based on the embodiments of the present invention shown in the drawings. Needless to say, the present invention is not limited to these examples.

Embodiment 1 FIGS. 1, 2 and 3 are sectional views showing a first embodiment of the present invention. FIG. 1 shows a half-moon shaped paper feed roller A6 in a cassette 36.
The state is shown in which the leading edge of the inner sheet 9 is conveyed to the cassette sheet feeding port 14 while being pressed downward by the resistance of the spring 51, and is attached coaxially to the half-moon shaped sheet feeding roller A6. The guide plate 1 is urged upward by a spring because the cam 11 lifts one end of the connecting rod 8.
A force that pushes 0 downward is generated, and the upper end of the guide plate 10 is lowered below the cassette paper feed port 14 so that the paper 9 is smoothly fed.

In FIG. 2, the sheet 9 is conveyed along the guide plate 10 by being sandwiched between the sheet feeding roller B7 and the tension roller 5, the sheet detecting switch 4 is turned on, and the sheet feeding roller C2 and the tension roller are passed through the PS plate 3. 1 shows the state of being sandwiched between the guide rods 10 and the cam 11 contacting the connecting rod 8 is not a circular portion, and as a result, the guide plate 10 is biased upward by the spring.

FIG. 3 shows a state in which the sheet 9 is further conveyed and the rear end of the sheet 9 is in contact with the guide plate. As described with reference to FIG. 3, the guide plate 10 is urged upward to move the cassette. Since the height of the paper discharge position 52 in the paper 36 and the height of the upper part of the guide plate 10 are the same, the rear end of the paper 9 is moved from the cassette 36 to the guide plate 1.
There is no bounce when moving to 0. Therefore, no sound is generated.

FIG. 4 (a) is an external view of the first embodiment of the present invention. Particularly, in FIG. 4 (b), the guide plate 10 not shown in FIGS. 1 to 3 is urged upward. The relation between the spring 13 and the guide 12 to which the spring is attached, and the connecting rod 8 and the guide plate 10 is shown as an arrow view.
The connecting rod 8 is attached to the central portion of the connecting rod 8 (cam 1
1) and the guide plate 10), and a branch is provided near the main body.

Embodiment 2 FIGS. 5, 6 and 7 are sectional views showing a second embodiment of the present invention. Instead of the connecting rod 8 and the cam 11, the guide 12 and the spring 13 in Embodiment 1, FIG. The solenoid 20 and the spring 21 are used as a vertical swinging device for the guide plate 10. More specifically, it is assumed that the sheet detection switch 4 is used, the guide plate 10 moves up and down within a specified range, and the solenoid 20 is below the guide plate 10. When the paper detection switch 4 is ON, the solenoid 20 turns off.
When FF and paper detection switch 4 are OFF, the solenoid is O
N.

FIG. 5 shows that the leading edge of the sheet is conveyed from the cassette 36 to the guide plate 10, and when the sheet feeding roller A6 rotates counterclockwise and the surface of the sheet feeding roller A6 contacts the sheet 9, the cassette rotating plate. The paper 9 is conveyed while pressing down. At that time, since the sheet detection switch 4 does not detect the sheet, the solenoid is turned on and the guide plate 10 is lowered, so that the sheet is conveyed without hindering the conveyance.

6 and 7 show that the rear end of the sheet 9 is conveyed from the cassette 36, and the cassette rotating plate was pushed up in FIG. 5, but in FIGS. 6 and 7, it returns to the original position. is doing. At this time, since the paper detection switch 4 is detecting the paper 9, the solenoid 20 is turned off and the force of the spring 21 is applied to the plunger, so that the guide plate 10 moves upward and the rear end of the paper 9 is moved. Even if the paper is separated from the cassette 36, the rear end of the paper 9 is little bounced and the rear end of the sheet 9 is conveyed to the guide plate 10. Therefore, the sound is reduced. The timing at which the guide plate 10 is moved up and down is determined by the sheet detection spring 4. First, the paper feed roller A6 is rotated to move the paper 9
Is transported. At that time, since the paper detection spring 4 is not detecting, the solenoid 20 of the guide plate is ON and the guide plate 1
0 goes down. The sheet is conveyed, the sheet detection switch 4 detects the sheet 9, and the solenoid 20 of the guide plate 10 is detected.
Is turned off, and the guide plate 10 moves up to serve as a conveyance guide. When the sheet 9 is conveyed and the sheet finishes passing through the sheet detection switch 4, the solenoid 20 of the guide plate 10 is turned off.
N, the guide plate 10 moves down, and the guide plate 10 moves up and down regardless of the size of the paper 9 or the like.

FIG. 8 shows a time chart in the second embodiment. While the copy button is pressed to feed the sheet and the sheet detection switch detects the sheet, the solenoid is turned off (the guide plate is biased upward).

Embodiment 3 FIG. 9 is a sectional view showing a third embodiment of the present invention,
Is a paper transport path, 31 is a half-moon roller, 32 is a transport roller,
33 is a paper detection switch, 34 is a guide plate, 35 is a solenoid, 36 is a cassette, 37 is a base plate of the apparatus, 38 is paper, 39 is a paper size detection sensor, 40 is a cassette paper feed port, and the guide plate 34 is The height of the sheet 38 is changed by the solenoid 35 at the start of feeding and at the end of feeding, as in the second embodiment.
The difference is that the OFF signal is input by software based on the information of the paper size detection sensor 39 without using the mechanical means using the paper detection switch of the second embodiment.

FIG. 10 shows a time chart in the third embodiment. Since there is a timing between the time when the copy button is pressed and the paper is fed and the paper detection switch is turned ON / OFF, and the time when the ON / OFF signal is actually given to the solenoid to move the guide plate up and down ( This tendency becomes stronger as the high-speed paper feeding device is turned on / off to the solenoid.
An F signal is given to control the timing of moving the guide plate up and down with high accuracy (changing the timing depending on the paper length).

FIG. 11 shows a flowchart of the third embodiment of the present invention. After the power is turned on, the size of the paper in the cassette is discriminated (100) and stored in memory.
When the copy button is pressed in the copy standby (101) state (102), the guide plate is lowered by the ON signal of the solenoid (103) and the half-moon roller rotates (1).
04), the paper is conveyed, and the paper detection switch is turned on (105). Copying starts (106), and the guide plate is raised by the OFF signal of the solenoid (107). Next, the timer is started (108), the paper size is discriminated from the initially stored paper size (109), and when a preset time has passed for each paper size, an ON signal is given to the solenoid to turn on the guide plate. It is lowered (110), and copying is completed (111).

Specifically, it is assumed that the paper size detection sensor 39 uses an optical sensor, the guide plate 34 moves up and down within a specified range, and the solenoid 35 is below the guide plate 34. The position of the optical sensor is on the base plate 37 holding the cassette 36, and several optical sensors are used according to the paper 38. Therefore, the optical sensor determines the paper size. The solenoid 35 is turned on and off by timing the upper and lower sides of the guide plate 34 according to the sheet 38. Usually, the guide plate 34 is lowered, the half-moon roller 31 is rotated, and after a few seconds, the guide plate 34 is raised and then lowered. For example, suppose that there is A4 size paper in the cassette. (A4 vertical size 2
97 mm), the paper speed is 50 mm / s, the distance from the cassette paper feed port 40 to the paper detection switch 33 is 30 mm, and two seconds later, copying is started,
In addition, the half-moon roller 31 rotates, and after 1.5 seconds, the guide plate 3
4 shall go up. T = {2A on the software
The formula of + (CB)} / A-1.5 is input.
Here, from the above example, A = 50 mm / s, B = 30 mm, C
= 297 mm, t = 5.76 s is obtained, and the guide plate 34 is lowered after 5.76 seconds. With such a configuration, high-speed paper feeding can be supported.

Others The present invention is not limited to the embodiments described above and shown in the drawings, and it is needless to say that the present invention can be appropriately modified and implemented without departing from the scope of the invention.

[0024]

According to the present invention, at the start of sheet feeding,
Since it is possible to automatically change the height of the guide plate at the end of feeding according to the total length of the paper, the noise generated when the trailing edge of the paper hits the guide plate at the end of paper feeding It is possible to select a paper feeding device that can prevent the occurrence of noise and has an excellent silent effect.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a first embodiment of the present invention.

FIG. 3 is a sectional view showing a first embodiment of the present invention.

FIG. 4A is an external view showing a first embodiment of the present invention. (B) It is the A arrow line view of the external view which shows the 1st Example of this invention.

FIG. 5 is a cross-sectional view showing a second embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a second embodiment of the present invention.

FIG. 7 is a cross-sectional view showing a second embodiment of the present invention.

FIG. 8 is a time chart of the second embodiment of the present invention.

FIG. 9 is a cross-sectional view showing a third embodiment of the present invention.

FIG. 10 is a time chart of the third embodiment of the present invention.

FIG. 11 is a flowchart of the third embodiment of the present invention.

FIG. 12 is a cross-sectional view of a conventional device.

FIG. 13 is a cross-sectional view of a conventional device.

FIG. 14 is a cross-sectional view of a conventional device.

[Explanation of symbols]

 1 Tension roller 2 Paper feed roller C 3 PS plate 4 Paper detection switch 5 Tension roller 6 Paper feed roller A 7 Paper feed roller B 8 Connecting rod 9 Paper 10 Guide plate (guide member) 11 Cam 12 Guide 13 Spring 14 Cassette paper feed Port 20 Solenoid 21 Spring 30 Paper transport path 31 Half-moon roller (paper feed roller) 32 Transport roller 33 Paper detection switch 34 Guide plate (guide member) 35 Solenoid 36 Cassette 37 Base plate 38 Paper 39 Paper size detection sensor 40 Cassette feed port 41 Tension roller 42 Paper feed roller C 43 PS plate 44 Paper detection switch 45 Tension roller 46 Paper feed roller A 47 Paper feed roller B 48 Guide plate (guide member) 49 Paper 50 Cassette paper feed port 51 Spring 52 Paper discharge position

Claims (5)

[Claims] 1. A sheet feeding device for feeding a sheet from a sheet accommodating section to an image processing section via a sheet guiding member, and a sheet feeding unit for feeding the sheet from the sheet accommodating section to the guide member. A guide member that guides the paper in a direction different from the paper feeding direction, a support unit that swingably supports the guide member, and the paper that is supplied to the guide member is conveyed to the image processing unit. When the conveying roller and the sheet storage portion side of the guide member are brought close to the sheet supply port at the start of feeding the sheet (first position), and the rear end of the sheet passes through the sheet supply port. And a drive unit for driving the guide member that swings the side of the guide member near the paper storage portion in a direction away from the paper supply port (second position). 2. The sheet feeding device according to claim 1, wherein at least a part of the guide member is a reversing guide member that reverses and conveys a sheet by 180 degrees. 3. The driving means for the guide member reciprocates by receiving a paper feed roller, a cam coaxial with the paper feed roller, and slidingly contacting the cam at one end, and reciprocating at the other end. 2. The paper feeding device according to claim 1, further comprising a drive mechanism that swings the guide member. 4. The drive means for the guide member includes a paper detecting means for detecting the paper fed to the guide member, and a moving means for moving the guide member to the first position or the second position. 2. The sheet feeding device according to claim 1, further comprising: a control unit that controls the moving unit of the guide member in response to a sheet size signal from a sheet detection signal of the sheet detection unit. 5. The guide member driving means includes a first detecting means for detecting a sheet size of a sheet storage portion, a second detecting means for detecting a sheet fed to the guide member, and the guide member. Moving means for moving to the first position or the second position, and controlling the moving means of the guide member in response to a sheet detection signal of the first detecting means and a sheet size signal of the second detecting means. The sheet feeding device according to claim 1, further comprising: