JP3217148B2 - Paper feeder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeder of an image forming apparatus such as a copying machine, a facsimile, a laser beam printer, etc., and more particularly to a paper feeder in which a large amount of paper is stacked on a vertically moving bottom plate in a paper storage unit. The present invention relates to a large-capacity sheet feeding device for feeding sheets in order from a higher-order sheet.

[0002]

2. Description of the Related Art Conventionally, a paper feeder capable of stacking a large amount of paper is disclosed in Japanese Patent Publication No. 1-60829, Japanese Utility Model Application Laid-Open No. 57-182.
As disclosed in Japanese Patent Application Laid-Open No. 748, there are many devices adjacent to the side of the image forming apparatus.

[0003] However, this configuration has a drawback that it occupies a large installation area of the machine. Further, in order to supply paper to such a device, it is necessary to lower the bottom plate to the lowermost position and stack the paper, so that the operator has to bend his / her hips and stack the paper, and the operability is extremely poor. .

Therefore, as shown in JP-B-63-63444 (1) and JP-A-3-211122 (2), the paper can be replenished at a high position by gradually lowering the bottom plate. A proposed mechanism has been proposed.

[0005]

However, in (1),
It is necessary to replenish the sheets after pulling out the large tray including the bottom plate driving section, and this forces the operator a great deal of operating power. Further, when the tray on which the sheets are stacked is pushed in, the alignment of the sheets is disturbed by the shock, which may cause a jam.

In the method (2), the sheet is set from above by opening the transfer device or the like located above the bottom plate without pulling the tray forward. Such a configuration in which the paper feeding means or the like touches the operator's hand when replenishing the paper has a drawback that not only gives anxiety to the operator but also is dangerous and may lead to damage of parts due to erroneous operation.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned drawbacks of the conventional apparatus, to provide a paper feeding apparatus capable of supplying paper at a high position and improving operability.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a paper storage unit comprising a box-shaped frame body which can be pulled out to the front side of a main body by a rail and has an open upper part. A bottom plate that loads and moves up and down a large amount of sheets, a bottom plate driving unit that raises and lowers the bottom plate, and a sheet feeding unit that feeds the stacked sheets from above. Is provided by a first means having a small tray for replenishing sheets on the bottom plate and a guide means for pulling out the small tray to the near side.

The object of the present invention is to provide, in the first means, transfer means for transferring the paper loaded in the small tray in the pulled-out state to the paper storage portion, and transfer drive means for driving the transfer means. This is achieved by a second means having:

[0010] The above object is also achieved by the second means, wherein the storage means for detecting that the paper on the small tray is stored in the paper storage section by the transfer means,
Height detecting means for detecting the top surface of the bottom plate or the paper stacked on the bottom plate; and detecting the end of paper storage based on a signal from the storage detection means, the top surface of the paper is positioned at a predetermined height. So that the bottom plate is lowered
Control means for returning the transfer means to the small tray.

The above object is also achieved by the third means, wherein the control means sets an appropriate time required for transferring the paper,
If the storage detecting means does not operate within this proper time, the fourth means performs control to return the transferring means to the small tray while displaying the jam during transfer on the display unit.

It is another object of the present invention to provide the second means, further comprising torque limiter means for transmitting a predetermined torque to the transfer drive means, wherein the torque value of the torque limiter means is lower than the drive torque of the drive source to transfer the paper. This is achieved by a fifth means for setting the torque in a range higher than the torque required for the operation.

In the third means, the third means is provided with a bottom plate detecting means for detecting the bottom plate at a predetermined position, and the control means, when the bottom plate is detected by the bottom plate detecting means, This is achieved by a sixth means for controlling the transfer means so as not to return to the small tray.

The object of the present invention is that, in the first means, the sheet storage section is a large tray, the bottom plate, the bottom plate driving means and the small tray are configured in the large tray, and the large tray can be pulled out from the main body. An integrated locking means for integrating the small tray and the large tray;
This is achieved by a seventh means provided with a handle at the front of the small tray.

[0015]

In the first means, a small tray for replenishing sheets on the bottom plate is provided at an upper part of the sheet storing section.
Since the operator is away from the floor, the operator can replenish the paper without bending his waist, thereby improving the operability.

In the second means, the sheets set in the small tray are automatically transferred to the sheet storage section, so that the operator does not have to take any trouble.

In the third means, since the storage detecting means can detect that the paper on the small tray has been transferred to the paper storage portion, the next paper transfer can be prepared.
In addition, since the upper surface of the stacked sheets can be controlled at an optimum height for the transfer by the height detecting means, no trouble occurs during the sheet transfer.

In the fourth means, the control means detects the jam during the paper transfer and returns the transfer means to the original position, so that the operator can easily remove the jam paper.

In the fifth means, the torque limiter slips when an overload occurs due to a paper jam or the like.
The transfer driving means can be prevented from being damaged.

In the sixth means, the bottom plate detecting means comprises:
Since the amount of loaded sheets can be detected, it is possible to prevent the sheets from being overloaded.

In the seventh means, since the locking means can pull out the small tray and the large tray while keeping them locked, it is possible to easily perform the jam in the paper storage part and the maintenance of the paper storage part.

[0022]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram of a copying machine to which the present invention is applied.

This copying machine has a three-stage paper storage section (paper supply section) 1a, 1 which is supported so as to be able to be pulled out toward the front of the paper.
b, 1c, the upper tier accommodates large sized paper such as A3, and the lower tier accommodates large quantities of small sized paper such as A4 and B5.

Since the lower paper storage section stores only small-sized paper, the width of the entire machine is the same as before even if the paper storage sections 1b and 1c are arranged side by side as shown in the figure.

FIG. 2 is a perspective view of the sheet feeding apparatus according to the embodiment, and FIG. 3 is a front view of the same, and is applied to the lower two rows in the copying machine of FIG.

The large tray 1 can be pulled out of the main body by a rail 2. The large tray 1 is provided with a bottom plate 3 on which sheets are stacked, a guide rod 4 for guiding the bottom plate 3 in a vertical direction, and a drive unit including a forward / reverse rotatable motor (not shown) for vertically moving the bottom plate 3. I have. Approximately 2,000 sheets can be stacked on the bottom plate 3. The large tray 1 is formed as a box-shaped frame with an open top, so that the paper can be brought into contact with a paper feed unit 5 that conveys the loaded paper to the image forming unit.

Small tray 6 located at the top of large tray 1
However, the outer rail 7-1 is supported by the large tray 1 so that it can be pulled out separately from the large tray 1. The small tray 6 includes an inner rail 7-2, a front plate 6-1 and a front plate 6-1.
Is constituted by a handle 6-2 fixedly mounted on the vehicle.

The small (supplementary) tray 6 can load about 500 sheets. Small tray 6
Sheet bundle P ₁ stacked is summer to allow automatic transfer to the apparatus rear as in FIG. 2.

[0030] Figure 4 is small tray is drawn out to the front, perspective view showing a state in which excisional sheet bundle P _1, and more particularly to excisional the sheet bundle P ₁ pull operator a small tray 6 on top, the transfer start FIG. 5 is a perspective view showing a state in which the button 15 is pressed, and FIG. 5 is a top view of the U-shaped plate shown in FIG.

The bundle of sheets is made up of a fixed auxiliary plate 8, slide plates 9 and 10, and a tip portion of a U-shaped plate 11 (hatched portion in FIG. 5).
11-3. The fixing auxiliary plate 8 is fixed to the main body. Position of the sheet bundle P ₁ is a front guide 12, the rear end guide 13, and is by connexion restricted to the front side guide 14. The front end guide 12 and the rear end guide 13 are
1 fixed. The front side guide 14 is supported while being urged to the rear side of the machine by a compression spring. The U-shaped plate 11 has an opening 11 in the center, which is larger than the area of the sheet.
Have -4, sheet bundle P ₁ from the opening 11-4
Drop. A rack gear 11-1 is fixed beside the U-shaped plate 11, and a pinion gear 11-2 is driven by a drive unit (not shown) including a forward / reverse rotation motor fixed to the inner rail 7-2. Are rotated in the forward and reverse directions, so that the U-shaped plate 11 itself becomes the groove 7 of the inner rail 7-2.
Reciprocate along -3.

The drive section is provided with a torque limiter for transmitting only a predetermined torque. The torque value is set within a range higher than the torque for moving the U-shaped plate 11 on which the sheets are loaded and lower than the rated torque of the motor as the drive source. Therefore, when the paper is caught in the reciprocating motion of the U-shaped plate 11, the torque limiter slips, so that the drive unit is not damaged.

Slide plates 9 and 10 and U-shaped plate 11
Slide and contract with each other as shown in FIG. When the small tray 6 is stored, the slide plates 9 and 10 and the U-shaped plate 11 (subordinate indicated by a solid line) fit within a distance L from the front of the machine to the end of the stacked sheets as shown in FIG. .

FIG. 6 is a perspective view showing a state in which the sheet bundle set on the small tray is set on the sheet bundle on the bottom plate.

In the process up to the sheet setting, the pinion gear 11- is triggered by the signal of the start button 15 described above as a trigger.
2 is driven to rotate so that the U-shaped plate 11 on which the sheet bundle P ₁ is stacked
To move. As the U-shaped plate 11 moves, the slide plates 9 and 10 are sequentially stored above the fixed auxiliary plate 8 (FIG. 3).

The transported sheet bundle P ₁ is moved to the back side guide 1.
The transfer is continued even if it contacts 6. That is, the transported paper stops there, but the U-shaped plate 11 moves further, so that the area of the portion 11-3 where the U-shaped plate 11 indicated by the hatched portion in FIG. Finally, the sheet bundle P ₁ slips off the U-shaped plate 11. On the other hand, the front side guide 14 abuts against the stopper 17 fixed to the large tray 1 as shown in FIG. 3, so that the compression spring secures a space for accommodating the bent paper.

[0037] 21 is a transfer completion sensor shaped plate 11 co detects the position has been completed transferring the sheet bundle P _1. By determining the time from the signal of the start button 15 to the signal of the transfer end sensor 21, the jam during the transfer can be detected.

An upper surface detecting sensor 22 detects the upper surface of the sheet bundle. The upper surface detecting sensor 22 detects the upper surface of the stacked sheets so as not to interfere with newly transported sheets.
Can be lowered to a predetermined position to be detected. Therefore, immediately after the sheet is set, the upper surface of the sheet bundle is lowered to a predetermined position to prepare for the next sheet. on the other hand,
When the upper surface of the sheet is lowered, the U-shaped plate 11 also moves toward the small tray 6.

Reference numeral 18 denotes a bottom plate detection sensor for detecting the bottom plate 3, which is installed near the bottom of the large tray 1. From the position where the bottom plate detection sensor 18 detects the bottom plate 3,
When the distance to the lower limit position and l _1, bottom plate detecting sensor 18 to the l ₁ can be set slightly larger than the substantially equal or l ₂ and the maximum height l ₂ of the paper can be stacked in a small tray 6 is installed ing. Therefore, as described above, the sheets are stacked one after another, and when the bottom plate 3 gradually descends and is detected by the bottom plate detection sensor 18, it is determined that the sheet can be supplied only once more. it can. Also, the bottom plate 3
If the sheet falls through the bottom plate detection sensor 18, it is determined that the replenishment of the sheet is completed, and the return of the U-shaped plate 11 to the small tray 6 is stopped. Then, the operator is informed of the completion of sheet supply from the display unit, and is prompted to close the small tray 6 in the pulled-out state.

Therefore, when the operator pushes only the small tray 6 back to the large tray 1, the torque limiter means in the drive section of the U-shaped plate 11 slides to allow the small tray 6 to be inserted. Further, as a development type, a fixing means for fixing the U-shaped plate 11 in the large tray 1 to the large tray 1 is installed, and the U-shaped plate 11 in the large tray 1 is fixed by the fixing means. By driving the U-shaped plate driving unit, the pinion gear 11-
By rotating the small tray 2, the small tray 6 can be automatically stored in the large tray 1.

FIG. 7 shows a locking mechanism between the small tray 6 and the large tray 1. Recess 7 arranged on inner rail 7-2
-4 is fitted to the outer rail 7-1.
It is rotatable by a rotsco solenoid 19 fixedly mounted on the vehicle. To release the lock, the claw portion 20-1 is moved to the position indicated by the broken line in the figure by energizing the lock solenoid 19. When the energization of the rotary solenoid 19 is stopped, the claw portion 20-1 is rotated to the solid line position by the return spring 20-2, and the large tray 1 and the small tray 6 are fixed. With the trays fixed in this way, the handle 6
When the operator pulls out -2, the large tray 1 including the small tray 6 is pulled out to the front.

Normally, only the small tray 6 is pulled out, so such a locking mechanism is not necessary. However, it is convenient when processing a jam in the sheet storage unit.

FIG. 8 is a flowchart of the control operation according to the present invention.

When the small tray 6 is pulled out and the paper supply button 21 disposed in front of the front plate 6-1 of the small tray 6 is pressed (S1), the bottom plate 3 is lowered (S2), and the upper surface of the paper is detected. The lowering of the bottom plate 3 is stopped, and the rotor solenoid 19 is stopped.
Is released (S3, S4, S5). When the operator sets a sheet on the small tray 6 and presses the start button 15 (S6), the transfer of the sheet starts (S7). When the transfer is completed (S8, S9), the bottom plate 3 is lowered again to lower the upper surface of the sheet to a predetermined position (S10, S11).
The lowering of the bottom plate 3 is stopped (S12), and if the bottom plate 3 is not detected (S13), the U-shaped plate 11 is returned to prepare for the next sheet transfer (S14). When the stacking amount of paper is larger than the specified value (ON in S13), the operator is urged to close the tray (S15). Then, the tray set detection is turned on (S16), and when the rotary solenoid 19 is turned on (S17), the sheet is prepared for feeding (S18).

As described above, the tray normally operated by the operator is only the small tray 6 separated from the floor, and when operated, the tray is an empty tray. Therefore, no operation force is required.

[0046]

According to the first aspect of the present invention, the small tray for refilling the sheets on the bottom plate is provided at the upper part of the sheet storing portion and is separated from the floor, so that the operator does not bend. The paper can be replenished, and the operability can be improved.

According to the second aspect of the present invention, since the sheets set in the small tray are automatically transferred to the sheet storage section, there is an effect that the operator does not need to take any trouble.

According to the third aspect of the present invention, since the storage detecting means can detect that the paper on the small tray has been transferred to the paper storage section, the preparation for the next paper transfer can be made. Further, since the height detecting means can control the upper surface of the stacked sheets at the optimum height for the transfer, there is an effect that no trouble occurs during the transfer of the sheets.

According to the fourth aspect of the present invention, since the control means detects the jam during the sheet transfer and returns the transfer means to the original position, the operator can easily remove the jam sheet.

According to the fifth aspect of the present invention, since the torque limiter slides when an overload occurs due to a paper jam or the like, it is possible to prevent the transfer driving means from being damaged.

According to the sixth aspect of the present invention, since the bottom plate detecting means can detect the amount of the stacked sheets, it is possible to prevent the sheets from being excessively stacked.

According to the seventh aspect of the present invention, the locking means can be pulled out while the small tray and the large tray are locked, so that the jam in the sheet storage section and the maintenance of the sheet storage section can be easily performed.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a copying machine to which the present invention is applied.

FIG. 2 is a perspective view of a sheet feeding device according to the embodiment of the present invention.

FIG. 3 is a front view of the sheet feeding device according to the embodiment of the present invention.

FIG. 4 is a perspective view showing a state in which a small tray of the sheet feeding device according to the embodiment of the present invention is pulled out to the front and a sheet bundle is set.

FIG. 5 is a top view of a U-shaped plate of the sheet feeding device according to the embodiment of the present invention.

FIG. 6 is a perspective view showing a state in which a sheet bundle set in a small tray of the sheet feeding device according to the embodiment of the present invention is set on a sheet bundle of a bottom plate.

FIG. 7 is a configuration diagram of a locking mechanism for a small tray and a large tray.

FIG. 8 is a flowchart of a control operation according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 large tray 2 rail 3 bottom plate 5 paper feeding means 6 small tray 7 rail (guide means)

Claims (7)

(57) [Claims] 1. A paper storage section comprising a box-shaped frame body which can be pulled out to the front side of a main body by a rail and has an open top, and a large amount of paper is loaded in the paper storage section. A bottom plate that moves up and down, a bottom plate driving unit that raises and lowers the bottom plate, and a paper feeding unit that feeds the loaded sheets from above. And a guide means for pulling out the small tray to the near side. 2. The apparatus according to claim 1, further comprising: a transfer unit configured to transfer the sheets loaded in the small tray in the pulled-out state to the sheet storage unit; and a transfer drive unit configured to drive the transfer unit. A sheet feeding device, characterized in that: 3. The bottom plate or the bottom plate according to claim 2, wherein storage detection means for detecting that the paper on the small tray is stored in the paper storage unit by the transfer means. Height detecting means for detecting the uppermost surface of the sheet, and upon detecting the end of sheet storage based on a signal from the storage detecting means, lowering the bottom plate so that the uppermost surface of the sheet is located at a predetermined height, Control means for returning the transfer means to the small tray. 4. The display unit according to claim 3, wherein the control unit sets an appropriate time required for the transfer of the sheet, and if the storage detecting unit does not operate within the appropriate time, the display unit displays the jam during the transfer. And a control to return the transfer means to the small tray. 5. The apparatus according to claim 2, further comprising torque limiter means for transmitting a predetermined torque to said transfer drive means, wherein the torque value of said torque limiter means is lower than the drive torque of a drive source, and the paper is transferred. A paper feeding device characterized in that the torque is set within a range higher than a required torque. 6. The apparatus according to claim 3, further comprising: bottom plate detecting means for detecting the bottom plate at a predetermined position, wherein the control means determines that the bottom plate is detected by the bottom plate detecting means. , So as not to return to the small tray. 7. A guide means according to claim 1, wherein said sheet storage portion is a large tray, said bottom plate, bottom plate driving means and small tray are formed in a large tray, and said large tray can be pulled out from a main body. And an integrated locking means for integrating the small tray and the large tray, and a handle on the front surface of the small tray.