JPS6216947A - Paper feed device - Google Patents

Abstract

PURPOSE:To surely separate paper sheet which are overlappedly conveyed, by floating up the paper sheets with the use of air jetted from first air nozzle to convey the same by means of a conveyer belt, and by generating a stagnation pressure between the paper sheets with the use of jet air from second air nozzles. CONSTITUTION:A suction duct 16 is connected at its downstream side to an air box 28, and jet air from first air nozzles 29 impinges upon the upper section of the leading end of paper sheets 21 which are therefore floated up. A conveyer belt 12 having absorbing holes is positioned right above the paper sheets 21, and absorbs and conveys the topmost one of the paper sheets 21. Jet air from second air nozzles 30 converges and impinges upon an air stream deflecting plate 31 which is inclined at an angle of alpha with respect to the upper surface of the paper sheets 21, and therefore, a stagnation pressure is created between the topmost one and the next one of the paper sheets 21. This stagnation pressure cancels out any suction force due to static electricity between both paper sheets, thereby it is possible to enhance the separation between paper sheets.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a paper feed device that takes out sheets stacked on a paper feed tray in order from the topmost sheet and supplies them to a copying machine, facsimile machine, or the like.

2. Description of the Related Art A typical paper feeding device takes out a large number of sheets of paper stacked on a paper feeding tray one by one, starting from the top one, and feeds them into a copying machine or the like.

Among these paper feeding devices, for example, Japanese Patent Laid-Open No. 60-020
In the device disclosed in Japanese Patent No. 900, the uppermost paper at the back of the paper on the paper feed tray is floated by an air flow from a first air nozzle group, and the floated paper is formed on a conveyor belt. The paper is attracted onto the conveyor belt by the suction force generated in the negative pressure hole, and at this time, an air flow from the second air nozzle group separates the uppermost sheet from the sheet immediately below it.

After the paper attracted to the conveyor belt is conveyed a predetermined distance, it is separated from the conveyor belt by blocking the negative pressure generated in the negative pressure hole, and is supplied onto the next conveyance path.

In this case, the paper feeding device main body and the paper feeding tray are constructed as separate subassemblies, and these are independently positioned via, for example, the frame of the copying machine main body. The paper feeding device main body and the paper feeding tray are positioned in a predetermined direction in consideration of the direction of air ejected from the first and second air nozzle groups.

By the way, in such paper feeding devices, the relationship between the position of air blowing from the air nozzle group and the position of the leading edge of the paper is an important element in the paper feeding function, but it is difficult to adjust the position setting. For example, if the height of the paper is too high relative to the air blowing position of the air nozzle, it will cause double feeding of paper, and conversely, if the height of the paper is too low relative to the nozzle air blowing position, it will result in paper suction failure. This results in the inability to transport the paper.

Problems to be Solved by the Invention As mentioned above, in conventional paper feeding devices, it is difficult to attach each component so that the relationship between the blowout position of the air nozzle group and the leading edge position of the paper is accurately determined. The problem is that it is quite difficult.

This has caused problems such as double feeding or paper jams due to poor precision in the position and orientation of the air nozzle group.

The present invention has been made in view of the above points, and the first and second air nozzle groups are mounted with respect to the main body of the paper feeding device and the paper feeding tray by increasing the accuracy of the position, thereby preventing double feeding of paper,
The purpose is to prevent paper jams, etc.

The problem. Means for Deciding In order to achieve the above object, the paper feeder of the present invention includes a suction means for suctioning the uppermost sheet of paper stacked on a removable paper feed tray; a first air nozzle group that levitates the uppermost sheet to a position where it can be sucked by the suction means; and a first air nozzle group that blows air between the uppermost sheet and the sheets below it. the first and second air nozzle groups; A nozzle box in which air nozzle groups are formed is rotatably supported, and first and second air nozzle groups are held by positioning means provided on the paper feed tray and non-positioning means provided on the nozzle box. Zuru.

According to the present invention, when the nozzle box is positioned at a predetermined position with respect to the paper feed tray and the rotation angle of this nozzle box is set to a predetermined rotation angle, the first and second air nozzles formed in the nozzle box are The group is positioned at the desired location and orientation.

Therefore, the uppermost sheet of paper stacked on the paper feed tray is levitated by air from the first air nozzle group, and the uppermost sheet of the levitated upper sheets and the paper immediately below it. Air is blown out from the second air nozzle group between the two through the air flow collision wall. This separates the topmost paper from the papers immediately below it,
Only the uppermost sheet of paper is suctioned by the suction means, and the uppermost sheet is conveyed in a predetermined direction by the conveyance means.

In this way, according to the present invention, the air from the first air nozzle group causes the uppermost sheet of paper on the paper feed tray to float, and there is a gap between the lifted uppermost sheet and the lower sheet. By actively blowing air from the second air nozzle group, the uppermost sheet and the sheets immediately below it can be separated, so that only the uppermost sheet can be transported by the transport means.

Example Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows the external structure of a copying machine to which a paper feeding device according to an embodiment of the present invention is applied. As shown in Fig. 3, the rail 3 allows it to be put in and taken out freely.

A paper feeder main body 4 is housed inside the copying machine main body 1 .

This paper feeding device main body 4 will be described in detail with reference to FIGS. 14 and 15.

First, a paper guide plate 25 is provided on the paper feed tray 2 for positioning the stacked papers 21.

Directly above the stacked sheets 21, a conveyor belt 12 is wound, which is rotated by a drive roller 14 and an idler roller 13 in six directions indicated by arrows in FIG. Conveyor belt 1
2 is provided with a suction hole (not shown), and a negative pressure is generated near the suction hole by suction of air from the vacuum box 15. The upstream side of the intake duct 16 connected to the vacuum box 15 is connected to a vacuum fan 17, and the downstream side thereof is further connected to a nozzle box 28 via a jet duct 18. A vacuum valve 26 for sucking the uppermost sheet of paper onto the conveyor belt 12 is provided in the middle of the intake duct 16, and downstream of the vacuum valve 26, air is supplied to a first air nozzle group 29 and a second air nozzle group 30, which will be described later. A relief valve 27 is provided for this purpose.

The first air nozzle group 29 is attached to the nozzle box 28 so that the ejected air hits the upper part of the leading edge of the sheets 21 being deposited, and the second air nozzle group 30 is inclined at an angle α with respect to the upper surface of the sheets 11. The nozzle box 28 is attached to the nozzle box 28 so as to blow the ejected air toward the air flow collision wall 31 provided at the nozzle box 28. To be more specific, the first
The air nozzle group 29 generates an air flow substantially parallel to the sheets of paper stacked on the paper feed tray 2 to levitate the uppermost sheets of paper to a position where it can be sucked onto the conveyor belt 12. It is designed to be moved. The second nozzle group 30 blows air between the suctioned uppermost sheet and the second sheet immediately below it to ensure separation of both sheets. The three second air nozzle groups 30 are oriented in the direction in which the air ejected from each other is concentrated, and when these air nozzle jets collide with the air flow collision wall 31, the uppermost sheet of paper and immediately below it are This creates a stagnant pressure between the uppermost sheet of paper and the sheet immediately below it, thereby canceling out the attractive force due to static electricity between the uppermost sheet of paper and the sheet immediately below it, thereby enhancing the separation effect between the two sheets. The air flow impingement wall 31 is inclined at an angle α with respect to the conveying direction of the stacked sheets 21, and thereby functions to increase the stagnation pressure.

The uppermost sheet of paper attracted to the conveyor belt 12 is conveyed in the direction of arrow B shown in FIG. It has become.

Next, the operation of the paper feeder main body 4 will be explained. First, the vacuum valve 26 is closed and the relief valve 27 is open. When the vacuum fan 17 is driven, the air flows through the relief valve 27 and the jet duct 18 to the nozzle box. Air is supplied to the first air nozzle group 29 and the second air nozzle group 28.
Air jets are ejected from each of the air nozzle groups 3° in a predetermined direction. □The air from the first air nozzle group 29 applies an air flow to the upper part of the paper stacked on the paper feed tray 2, and the air supplied from the other second air nozzle group 30 hits the air flow collision wall 31. The paper is fed so as to create stagnation pressure between the upper paper and the paper directly below it.

Therefore, the first air nozzle group 29 mainly floats the uppermost sheet of sheets loaded on the paper feed tray 2, and the second air nozzle group 29 separates the uppermost sheet from the sheet directly below it. It is measured by 30.

When the vacuum valve 26 is opened and the relief valve 27 is closed, the action of the vacuum fan 17 generates negative pressure in the vacuum bogges 15 through the intake duct 16, and this negative pressure is formed on the conveyor belt 12. This occurs in the suction hole 20 (see FIGS. 3 and 4), which sucks the uppermost sheet onto the conveyor belt 12. At this time, when the negative pressure in the intake duct 16 rises to a predetermined value or more, the relief valve 27 is opened.

When a predetermined period of time has elapsed after the roll valve 26 was switched from the closed state to the open state, a clutch (not shown) connected to a drive source (not shown) is turned on, and the drive roll 1
4 in the direction of arrow A to drive the conveyor belt 12 in the direction of arrow A.

The paper transported by the transport belt 12 is transported by the transport roll 22.
, passes through the pinch roll 23 and the photosensor 32 . When the photosensor 32 detects the leading edge of the passing paper, the clutch is turned off to stop the operation of the drive roll 14 and the vacuum valve 26 is set to the leap state. As a result, the paper that had been sucked up to that point is peeled off from the conveyance belt 12, and the paper is supplied via the conveyance roll 22 to, for example, a platen glass (not shown) of a copying machine.

Figures 3 and 4 are cross-sections taken along the line ■-1 in Figure 1, with the paper feed tray 2 pulled out (Figure 3) and the paper feed tray 2 retracted (Figure 4). Figure) is shown.

The paper feeder main body 4 is supported by a bin (not shown) at the rear side of the copying machine main body 1 shown in FIG. 2, and is screwed to the copying machine main body frame (not shown) at the front side. The nozzle box 28 is rotatably supported on the sub-frame 33 of the paper feeder main body 4 on the back side (the left side in FIG. 3) of the copying machine main body 1, and on the front side (the right side in FIG. 3). 0 port 3 is installed. Further, a guide 35 is attached to the nozzle box 28 to guide the paper being conveyed.
Furthermore, the pinch roll @23a of the pinch roll 23 is held by a spring 45 on the guide plate 36, as shown in FIGS. 10 and 11.

The positioning of the nozzle box 28, which is a feature of the present invention, will be explained based on FIGS. 3 to 7.

When paper feeders 1 to 2 loaded with paper are inserted into the copying machine main body 1, that is, the paper feeder main body 4, the leaf spring 37 provided on the paper feed tray 2 pushes up the rollers 34, and the paper is fed roughly. When paper tray 2 is inserted to the back, nozzle box 2
8 is gradually pushed upward. Here, paper feed tray 2
Bin 4 for nozzle positioning provided in the frame 38 of
3.44 enters the bottle hole 40.41 provided in the bracket 39 that supports the roller 34. When the paper feed tray 2 is further inserted into the back side, the nozzle box 28 is further pushed up, the conveyance roll 22 and the pinch roll 23 form a nip, and the bin 42 provided on the guide guide 35 is inserted into the subframe 33. come into contact with At this time, the nozzle box 28 is positioned as shown in FIG.

Here, the bottle hole 40.41 into which the bottle 43.44 having a circular cross-sectional shape is inserted is an elongated hole in the left-right direction in FIGS. 5 and 6. The horizontal positioning of the nozzle box 28 is determined by the fit between the bins 43, 44 and the bin holes 40, 41, and the vertical positioning of the nozzle box 28 is determined by the butt between the bins 42 and the subframe 33. It has become.

The spring characteristics of the spring 45 and the leaf spring 37 are such that the torque T1 around the support shaft of the nozzle box 28 causes the pinch roll 23 to maintain the proper position and orientation of the first air nozzle group 29 and the second air nozzle group 30. Holding spring 4
The torque is selected to be larger than the torque T2 according to No. 5.

The connection portion between the nozzle box 28 and the jet duct 18 will be explained.

As shown in FIGS. 8 and 9, the blower duct 18 is fitted into a flange 48 attached to the rear frame 47 of the sheet feeder main body 4, and a sleeve 49 is attached to the flange 48. It is installed so that it can move in the thrust direction. The sleeve 49 is connected to the coil spring 5
A highly elastic sealing material 51 made of high-density urethane foam or the like is provided between the sleeve 48 and the nozzle box 28. Such a configuration prevents air leakage even when the nozzle box 28 rotates about the fulcrum 52.

When a paper jam occurs inside the paper feeder main body 4, the paper feed tray 2 is first pulled out in accordance with the paper jam indication on the display 5 of the copying machine main body 1. When the paper feed tray 2 is pulled out, the bottom plate of the tray is warped and the nozzle box 28 is slightly rotated clockwise in FIG. . Therefore, the jammed paper is released from the restraint state and can be easily removed.

Also, when paper feed tray 2 is pulled out, nozzle box 2
8 descends from the position shown in Fig. 12 to the position shown in Fig. 13, the paper feed path gap widens, and the nozzle box 2
The pinch roll 23 supported by 8 is lowered. Therefore, the roll nip between the transport roll 22 and the pinch roll 23 is released, so that the workability when removing paper jams is considerably improved.

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, as described above, the positional relationship between the leading edge position of the paper placed on the paper feed tray and the air blowing position of the nozzle box is set accurately and accurately. By minimizing the cumulative cross-over between the two positions, it is possible to reliably transport sheets one by one without double feeding or overlapping.

In addition, when the paper feed tray is pulled out, the positioning of the nozzle box is released, so the nozzle box rotates, which significantly improves the workability of removing paper jams when paper jams occur inside the paper feeder main body. .

[Brief explanation of the drawing]

Fig. 1 is an external configuration diagram of an example of a copying machine equipped with the paper feeding device of the present invention, Fig. 2 is a perspective view of the copying machine shown in Fig. 1, and Figs. 3 and 4 are the paper feeding device. Main unit and paper feed 1-Ray Figure 1 ■-■
Line sectional views, Figures 5, 6, and 7 are main part explanatory views for explaining the insertion operation of the paper feed tray, and Figures 8 and 9 are diagrams showing the connection between the nozzle box and the jet duct. Fig. 10 is a schematic plan view showing the holding part of the pinch roll, Fig. 11 is a schematic side view showing the holding part of the pinch 1 call in Fig. 10, and Figs. 12 and 13 are paper jams. Figure 14 is a schematic diagram showing the operation of the paper feeder during removal; Figure 14 is a schematic diagram showing an embodiment of the paper feeder of the present invention; Figure 15 is a diagram showing the first and second air nozzle groups and the feeder. FIG. 3 is a schematic perspective view showing the positional relationship with paper on a paper tray. 1... Copying machine main body, 2... Paper feed tray, 4...
・・Paper feeding device main body, 12・・Transport belt, 14・
... Drive roll, 15 ... Vacuum box, 16 ... Intake duct, 17 ... Vacuum fan, 18 ... Fumes duct,
20... Suction port, 21... Paper, 28...
... Nozzle box, 29... First air nozzle group, 30... Second air nozzle group, 31... Air flow collision wall, 40.41... Bottle hole, 42... Pin, 43
．． 44...bin, 52...fulcrum.

Claims (1)

[Claims] a suction means for suctioning the uppermost sheet of sheets stacked on a removable paper feed tray; a conveyance means for transporting the sheet sucked by the suction means; and a conveyance means for transporting the uppermost sheet of paper by the suction means. A first air nozzle group that levitates the paper to a position where it can be sucked, a second air nozzle group that blows air between the uppermost paper and the paper below it, and the air nozzle group that switches the air flow direction from the second air nozzle group and an air flow collision wall having an inclined surface with respect to the upper surface of the stacked sheets, wherein the first and second
A nozzle box in which air nozzle groups are formed is rotatably supported, and the first and second air nozzle groups are held by positioning means provided on the paper feed tray and positioning means provided on the nozzle box. A paper feeding device characterized in that: