JP2901993B2 - Paper feeder - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeding device for supplying paper in office machines such as a copying machine, a facsimile, and a printer.

2. Description of the Related Art Conventionally, a paper feed cassette for storing sheets in a stacked state is provided so as to face a paper feed roller, and the uppermost layer paper is pressed against the paper feed roller to separate and feed the sheets one by one. When a sheet other than the sheet cassette is used, a sheet feeding apparatus that supplies sheets one by one by a manual guide plate is often used.

Problems to be Solved by the Invention The conventional manual guide plate has poor workability because sheets can be inserted only one by one. This is because the manual guide plate is fixedly attached at a fixed position. Here, as shown in FIG. 6, when a plurality of sheets 51 are stacked on the manual guide plate 50, the position of the top sheet 51, the middle sheet 51, and the bottom sheet 51 in the stacking direction is different. Are different. Middle layer paper
When the level of 51 is matched between the feed roller 52 and the reverse roller 53, the uppermost sheet 51 is
, And the lowermost sheet 51 contacts the reverse roller 53, and it is difficult to make the feed amount of the uppermost sheet 51 equal to the feed amount of the lowermost sheet 51.

Means for Solving the Problems In a paper feeder provided with a paper feed cassette for storing paper in a stacked state facing a paper feed roller, and wherein the paper is pressed against the paper feed roller, A manual guide plate for supporting a large number of sheets in a stacked state is provided between the paper guide roller and the paper feed roller, and an auxiliary manual guide plate is provided at an end of the manual guide plate in a direction facing the paper feed roller. Pressing means for connecting the auxiliary manual guide plate to the paper feed roller side is provided so as to be freely undulated.

When using paper other than the paper in the paper cassette, a manual guide plate is positioned between the paper cassette and the paper feed roller, and the paper in the paper cassette comes into contact with the paper feed roller by pressing means. Thus, as the number of sheets on the manual guide plate decreases, the auxiliary manual guide plate can be displaced toward the paper feed roller. Thus, a large number of sheets can be stacked on the manual guide plate to efficiently perform the sheet feeding operation, and can be fed with a uniform feed amount while maintaining the level of the uppermost layer sheet constant. .

Embodiment An embodiment of the present invention will be described with reference to FIGS. FIG. 5 shows a part of the inside of a housing of an office machine such as a copying machine, a facsimile, a printer, etc., wherein 1 is a side plate constituting a frame, and only one side is shown; It is arranged to face. A paper cassette 2 is detachably mounted on these side plates 1. As shown in FIGS. 1 to 4, the paper feed cassette 2 has a cassette case 3 having an upper surface opening and a mounting plate 5 for laminating a large number of sheets 4 mounted on the cassette case 3 by a hinge 6 so as to be able to move up and down. A pressing plate 8 serving as a pressing means is inserted into an opening 7 formed on the lower surface and the front surface of the case 3. At the base of the pressing plate 8 is fixed an angular shaft 9 which is connected to a driving unit (not shown) and reciprocates. The side plate 1 has a paper feed roller 10 located at the upper front of the paper feed cassette 2, a feed roller 11 located at the front of the paper feed roller 10, and a reverse roller facing the lower portion of the feed roller. 12 are rotatably held.

Then, a pair of paper guides that slide in the left and right direction
A manual guide plate 14 having a support 13 and an auxiliary manual guide plate 15
For pivotal connection. As shown in FIG. 5, pins 17 are erected on both sides of the manual guide plate 14, and these pins 17 are rotatably held by the side plate 1. Further, guide grooves 19 are formed in the side plate 1 to slidably hold pins 18 protruding from both sides of the auxiliary manual guide plate 15 on the free play end side. A concave portion 20 is formed to bend. Further, a protrusion 21 is formed on one upper side of the manual guide plate 14, and a photoelectric detector 22 whose optical path is blocked by the protrusion 21 is fixed to one side plate 1.

Further, as shown in FIGS. 1 to 4, one end of the auxiliary manual guide plate 15 resiliently protrudes from the upper surface of the auxiliary manual guide plate 15 and is rotated by the pressure of the sheet. lever
23, and a sheet set detector 24 that detects the presence or absence of a sheet on the manual guide plate 14 by detecting the operation of the other end of the detection lever 23. Further, in the vicinity of the paper feed roller 10, a detection lever 26 urged in a counterclockwise direction and rotated about a support shaft 25, and a protrusion 2 of the detection lever 26 are provided.
There are provided photoelectric conversion type sheet position detectors 29 and 30 whose optical paths are blocked by 7, 28. The detectors 22, 24, 2
A drive unit (not shown) controlled by the detection signals 9 and 30 is connected to the square shaft 9.

In such a configuration, FIG. 1 is a vertical sectional side view showing a state in which the paper 4 in the paper feed cassette 2 is supplied. That is, since the square shaft 9 is driven by the driving unit and rotates counterclockwise together with the pressing plate 8, the mounting plate 5 pressed by the pressing plate 8 pushes up the sheet 4. At this time, the detection lever 26 is pushed by the paper 4 and rotates clockwise, and the paper position detector 29 detects the protruding piece 27 and controls the driving unit of the pressing plate 8, whereby the pressing plate 8 The rotation range is determined, and the height position of the sheet 4 with respect to the feed roller 10 and the feed roller 11 is determined to be an optimum position.

When using paper other than the paper 4 in the paper feed cassette 2, as shown in FIG.
Rotate 14 clockwise. At this time, since the lower portion of the manual guide plate 14 is displaced forward, the pins on both sides of the auxiliary manual guide plate 15 are displaced.
18 is guided by the guide groove 19 of the side plate 1 and moves forward. That is, the manual guide plate 14 is laid down from the vertical position to the backward tilted position, and the auxiliary manual guide plate 15 rotates between the support shaft 16 and the front portion of the paper feed cassette 2 and the paper feed roller 10. Is displaced.
At this time, the photoelectric detector 22 is turned off, and the driving unit rotates the pressing plate 8 in the clockwise direction together with the angular axis 9 by this signal. That is, the sheet 4 and the mounting plate 5 of the sheet cassette 2 are displaced downward. In this state, another sheet 31 can be placed on the manual guide plate 14 and the auxiliary manual guide plate 15 in a stacked state. In this state, as shown in FIG.
The paper set detector 24 detects the movement of the detection lever 23 by the pressure of the paper 31, and the drive unit moves the pressing plate 8 to the square shaft 9 as shown in FIG. And is rotated counterclockwise. This pressing force is transmitted to the auxiliary manual guide plate combination 15 and the detection lever 26 via the placing plate 5 and the paper 4 of the paper feed cassette 2, and the auxiliary manual guide plate 15 transfers the paper 31 to the paper feed roller 10. And the sheet set detector 30 detects the protruding piece 28 of the detection lever 26. The operation of the drive unit for driving the square shaft 9 is controlled by the detection signal of the paper set detector 30,
Thereby, the height of the sheet 31 of the auxiliary manual guide plate 15 is maintained at an appropriate position. This paper 31 is supplied by a paper feed roller
When the number of sheets 31 on the auxiliary manual guide plate 15 decreases, the detection signal of the sheet position detector 30 changes, and the driving unit is driven by this detection signal.
Thus, the auxiliary manual guide plate 15 can be displaced toward the paper feed roller 10 as the number of sheets 31 on the manual guide plate 14 decreases. At this time, since the pin 18 is located in the concave portion 20 formed upward in the back of the guide groove 19, the upward movement of the auxiliary manual guide plate 15 is not hindered. Therefore, it is necessary to stack a large number of sheets 31 on the manual guide plate 14 to efficiently perform the sheet feeding operation, and to maintain the level of the uppermost sheet 31 constant and feed the sheet 31 with a uniform feed amount. Can be. Note that both sides of the sheet on the manual guide plate 14 are guided by the sheet guide 13. These paper guides 13 are
The position can be adjusted according to the width of. Further, since the paper 31 on the manual guide plate 14 can be pressed against the paper feed roller 10 by using the pressing plate 8 for pressing the paper 4 in the paper feed cassette 2, the number of components can be reduced.

Effect of the Invention Since the present invention is configured as described above, when using paper other than the paper in the paper feed cassette, the manual guide plate is positioned between the paper feed cassette and the paper feed roller to feed the paper. The paper in the cassette is brought into contact with the paper feed roller by the pressing means, and as the number of sheets on the manual guide plate decreases, the auxiliary manual guide plate can be displaced toward the paper feed roller.
A large number of sheets can be stacked on the manual guide plate to efficiently perform the sheet feeding operation, and the level of the top layer sheet can be maintained constant to feed the sheet with a uniform feed amount. Since the pressing means for pressing the paper on the paper feed cassette toward the paper feed roller and the pressing means for pressing the paper on the auxiliary manual guide plate toward the paper feed roller are shared, the paper in the paper feed cassette is used. Because the paper on the manual guide plate can be pressed against the paper feed roller using a pressing unit that presses
This has the effect that the number of parts can be reduced.

[Brief description of the drawings]

1 to 5 show an embodiment of the present invention.
FIG. 1 is a vertical sectional side view showing a state in which the paper in a paper feed cassette is used, and FIGS. 2 and 3 are longitudinal side views showing a process in which a manual guide plate is advanced between a paper feed cassette and a paper feed roller. FIG. 4, FIG. 4 is a longitudinal side view showing a state in which the paper on the manual guide plate is used, FIG. 5 is a perspective view showing a support structure of the manual guide plate, and FIG. 6 is a side view showing a conventional example. is there. 2 paper feed cassette, 4 paper, 8 pressing means, 10
… Feed roller, 14… Manual guide plate, 15… Auxiliary manual guide plate, 29, 30… Paper position detector, 31… Paper

Claims (4)

(57) [Claims] A sheet feeder for storing sheets in a stacked state opposed to a sheet feed roller, wherein the sheet is pressed against the sheet feed roller; A manual guide plate that supports a large number of sheets in a stacked state is provided between the paper guide roller and the paper guide roller so that the auxiliary manual guide plate can be moved up and down in a direction facing the paper feed roller at an end of the manual guide plate. And a pressing unit for pressing the auxiliary manual guide plate toward the paper feed roller. 2. A pressing means for pressing a sheet on a sheet cassette toward a sheet feeding roller and a pressing means for pressing a sheet on an auxiliary manual guide plate toward a sheet feeding roller. The sheet feeding device according to claim 1, wherein 3. The sheet feeding device according to claim 1, further comprising a sheet position detector for detecting the position of the uppermost sheet near the sheet feeding roller. 4. The sheet feeding device according to claim 3, wherein the operation of the driving unit of the pressing means is controlled by a detection signal of the sheet position detector.