JPS58100866A - Original feeder - Google Patents

Abstract

PURPOSE:To securely prevent the backward end of an original from invading over a guide members at the time of switch-back, by allowing the force of a pressing roller to an original feed belt in the direction at an acute angle to the positive belt feed direction. CONSTITUTION:An original feed belt 30 of a switch-back system is pressed toward a guide member 10 with a pressing roller 33 mounted rotatably on the lower end of an arm 35 at an obtuse angle to the positive feed direction of the belt 30. The arm 35 is energized clockwise, and a pressing force acts on the belt 30 at an acute angle. Therefore, during the positive feed, since the roller 33 is displaced anticlockwise by the component of the drive force of the belt, the pressing force is weakened, and the original is smoothly fed by a suitable force. At the time of switch-back, since the roller 32 is displaced clockwise in the reverse direction, the pressing force is raised, thus permitting the backward end of the original not to rise over the step 11 of the stopper, and to be securely prevented from invading over a guide member 10.

Description

Detailed Description of the Invention Technical Field The present invention relates to a document feeding device used for copying. Specifically, the present invention relates to a document feeding device used for copying. Specifically, the document feeding device conveys a document from a paper feed section via a conveyor belt onto a document glass, and then conveys the document through a guide member and onto a document glass. This is a so-called switchback in which the document is positioned by rotating the bell 4 in the opposite direction to slightly reverse the document and bringing the trailing edge of the document into contact with the stepped portion of the flange formed at the tip of the guide member. The present invention relates to an original document feeder of this type.

Prior art guide member stop v7jIt-On the inner surface of a sliding conveyor belt, four pressing rollers are spring-biased in a direction perpendicular to the conveyor belt, and these pressing rollers cause the conveyor belt to become a guide member. A document feeding device is known which is configured to press a document onto the upper surface with an appropriate pressing force. By pressing the conveyor belt (conveyor bell) against the guide member side with an appropriate pressing force, it is possible to prevent the original from being distorted when the original is forwardly fed, and also to prevent the original from being raised from the stopper stage at the rear end of the original to the top surface of the guide member when the original is being fed backwards. This is for prevention.

However, as described above, in the conventional device 1, the conveyor belt is spring-biased in the right angle direction toward the guide member by the pressing rollers, so the pressing force changes regardless of whether the conveyor belt moves in the forward or reverse direction. Therefore, if the pressing force of the presser is increased to prevent the trailing edge of the document from running over the document, the load on the document during normal document feeding will be excessive, and conversely, the load on the document during normal document feeding will be increased. - If properly carried out, there was a problem in that it would not work to prevent documents from running over when reversely fed. -Purpose The present invention provides a method for smoothly conveying documents by applying appropriate pressing force without causing distortion due to excessive load on the document. To provide a document feeding device which ensures document conveyance in a proper state during switchback, and which does not cause the inconvenience of the trailing edge of the document running over the upper surface of a guide member from a stopper step during switchback.

Features of the Invention In the document feeding device of the present invention, a pressure roller applies a pressure force to the conveyance belt F from an oblique direction, and when the document is forwarded, the pressure roller is applied by a component of the conveyance force of the conveyance bell F. The present invention is characterized in that the pressing force of the pressing member V is decreased, and the pressing force of the pressing member V is increased by a component of the conveying force of the conveying belt when the document is reversely fed.

Embodiments FIGS. 1 to 6 show a first embodiment of a document feeder according to the present invention.
An example is shown, and the paper feed section l, the guide member lO,
It is composed of an original glass 20, a conveyor belt 30, and a paper ejecting section 40, and a scanning exposure device 1j is installed below the original glass 20.
50, a photosensitive drum 560 is installed.

In the paper feed section 1, a paper feed path 4 is formed by guide plates 2 and 3.
The paper feed path 4 is provided with a document feed detection sensor 5, a stopper claw 6, an opposing pinch roller 7, and an auxiliary roller 8. The paper feed detection sensor 5 is turned on when the leading edge of the document passes, and is turned off when the trailing edge of the document passes. The stopper claw 6 always enters the paper feed path 4 and once locks the leading edge of the inserted document, but a release solenoid (not shown) operates with a certain time delay based on the leading edge detection signal of the sensor 5. tM1 rotates clockwise in the figure and retreats from the paper feed path 4. Pinch roots 7 is always auxiliary reeler 8
Although the paper feed path 4 is opened by moving away from the paper feed path 4, the paper is crimped onto the auxiliary field 28 by a crimping solenoid (not shown) which operates with a certain time delay based on the tip detection signal of the sensor S. After the pinch roller 7 is pressed, a drive solenoid (not shown) turns on the auxiliary roller 8, and the auxiliary roller 8 is rotated clockwise in FIG.

The release solenoid for the striped collar claw 6, the pressure solenoid for the pinch rotor, and the drive solenoid for the auxiliary roller 8 are each turned off with a certain time delay in response to the rear end detection signal of the sensor 5.

The guide member IO is installed between the end of the document glass 20 and the paper feed sl, and its upper surface is inclined downwardly from the end of the paper feed path 4, and the tip is a stopper step 11. ing. Further, as clearly shown in FIGS. 4 and 5, a recess 12 and a projection 13 are formed in the document conveyance direction at the top end.

The conveyor belt 30 has a drive roller 31 and a tension roller 3.
2, and is stretched between the presser t233 and the presser stomach.
The drive 4-231, which is pressed from the inner surface of the belt 30 by the belt 39 and can rotate forward and backward while slidingly contacting the upper surface of the guide member 1o and the upper surface of the original glass 2°, moves in the forward direction shown by the arrow M or in the direction shown by the arrow B. It is driven in the reverse direction shown. this transport bell)
The forward feed, reverse feed, and stop of the paper feed detection sensor 30 are appropriately controlled by a combination of the on/off of the paper feed detection sensor 5 and a timer.

As shown in FIGS. 2 and 3, the tension roller 32 is
It is rotatably attached to a bearing 23 provided in a guide hole 22 of the frame 21 so as to be movable in the lateral direction, and a tension coil spring 2r1 whose both ends are fixed to the disk 24 fixed to the bearing 23 and the frame 21 moves leftward. (to the right in FIG. 1).

The pressing roller 33 will be explained with reference to FIGS. 4 to 6. The pressing arm I233 is supported by the shirt 34, and the shaft 34 is rotatably supported by the T[1 portion of the arm 35. The upper end portion of the arm 35 is rotatably supported by a pin 36 fixed to the frame 21. The arm 35 is urged clockwise in the drawing by a spring 38 with the bin 36 as the center. A stopper bin 37 prevents the arm 35 from rotating more than necessary. Next press) 4 33, arm 35, bottle 3
6, etc., the suppressor 1233 attached to the arm 35 via the shaft 34f is pivotally supported by the pin 36 at the upper end, and the 9-arm 3S is attached to the conveyor belt 30.
The conveyor belt 30 is brought into contact with the conveyor belt 30 at an appropriate angle counterclockwise in the drawing from the perpendicular position to the conveyor belt 30 .

That is, the arm 35 forms an obtuse angle with respect to the normal feeding direction of the conveyor belt 30. In the case of the belt, the pressing force 33, which can move on a circle centered on the pin 36t, exerts an elastic pressing force on the belt 30 in its tangential direction, and this pressing force is applied to the belt 30.
The load is applied to the belt 2 obliquely from an acute angle direction with respect to the zero forward feeding direction. The roller 9 is a presser roller that is rotatably and vertically movable and presses the outer side of the conveyor belt 30 so that it comes into sliding contact with the armpit glass 20.

In the paper ejection section 40, a paper ejection passage 44 is formed by guide plates 41 and 42, and the end of the guide plate 42 extends from above the conveyor belt 30 to above the paper feed section l, forming an ejection tray 43. In addition, a document discharge detection sensor 45 and a pair of discharge rollers 46, 46 are installed in the paper discharge path 44.

The discharge detection sensor 45 is turned on when the leading edge of the document has passed, and turned off when the trailing edge of the document has passed. Exhaust p-ra 46
-46 is rotationally driven by the tip detection signal of the sensor 45,
Rotation is stopped with a certain time delay in response to a rear end detection signal from the sensor 45.

On the other hand, the scanning exposure device 50 includes an exposure lamp 51 and a cellar 52.
55, a lens 56, and a photosensitive drum 60 which can be driven to rotate clockwise in FIG. 64 well-known imaging elements are arranged.

Next, the operation will be explained. First, when a document is inserted into the paper feed path 4, its leading end is once locked by the stopper claw 6.

After the leading edge of the document is detected by the paper feed detection sensor 5,
After a predetermined period of time, the pinch row 27 presses the auxiliary member 0-98 to pinch the document, and then the stopper claw 6 also retracts the paper feed path 4.Furthermore, the auxiliary roller 8 starts to be driven, and at the same time the conveyor belt ) 30 starts to be driven in the direction of the arrow. After forwarding the original for a certain period of time, the original is placed on the original glass 20.
When the conveyor belt 30 is conveyed to the top, the drive of the conveyor bell 30 is temporarily stopped, and this time it is reversely driven in the direction of arrow B. Due to this reverse drive, the document is switched back, and the rear end of the document is moved backward to the guide member 10.
Please contact me further. This determines the exposure position of the original. Thereafter, a well-known copying operation is performed.

When the copying operation is completed, the conveyance bell is activated by the completion signal)3
0 is driven in the forward direction, and the document is discharged from the paper discharge path 44 onto the refill tray 43.

In the above-described operation, when the document is forwarded normally, that is, when the conveyor belt 30 is driven in the direction indicated by the arrow, the relationship Fi between the suppressor 033 and the conveyor belt 30 is as shown in FIG. In this case, when the conveyor belt 30 is driven in the direction of the arrow,
A component of the driving force acts on the pressing roller 33 and applies rotational force in the counterclockwise direction.

As a result, the pressing force 433 is slightly displaced counterclockwise,
The conveyor belt 30 also rises a little, thereby slightly weakening the document pressing force. Therefore, smooth conveyance with appropriate pressure is ensured without excessive frictional force acting on the original.

On the other hand, when switching back the document, that is, when the conveyance belt t30 is driven in the direction of arrow B, the relationship between the pressing roller 33 and the conveyance belt 30 is as shown in FIG. In this case, when the conveyor bell) 30 is driven in the direction of arrow B, a component of the driving force is added to the pressing force by the presser 433, and as a result, the presser Et3B is slightly displaced clockwise, and the conveyor The bell) 30 is also pushed slightly downward to close the gap with the upper end of the stopper step 11. Therefore, it is possible to reliably prevent the rear end of the reversely fed document from exceeding the stopper step portion 11 and rising onto the upper surface of the guide member IO.

The stopper pin 37 comes into contact with the arm 3I at an appropriate position, and prevents the pressing roller 33 from applying an excessive load to the belt 30 in the case of reverse feeding.

FIG. 7 shows a second embodiment. In Jin's example, the first pressure is 0.
Two rollers, 331 and the second pressing force BB2, are used, and these are attached to the inverted V-shaped arm 5350. In this case, the first pressing roller 331 mainly plays the role of preventing the document from riding up when the document is reversely fed.
The second pressing force 11332 plays the role of appropriately suppressing the original via the belt 30 during forward feeding of the original. The first pressing roller 331 is supported by a shaft 7) 341, and this shaft 7) 34
1 is rotatably supported on the lower end portion of the right side (in the drawing) of the inverted V-shaped arm 350. Further, the second pressing roller 332 is supported by the shirt 7) 342, and this shirt 7) 342 is
It is rotatably supported on the left (on the drawing) lower end portion of the glyph-shaped arm 350. The arm 350 is rotatably supported by a pin 360 fixed to the frame 21 at its upper end. Therefore, the second pressing roller 332 applies its pressing force to the conveying belt 30 from the obtuse angle direction with respect to the normal feeding direction of the conveying belt 30 on the front side of the conveying belt 30 in the normal feeding direction from the first pressing roller 0331. .

381 and 382 each have one end fixed to the frame 21 and are biased from the arms 350 and 11 by a spring. 370 is a stopper bin that prevents the first suppressing stiffness 331 and the second pressing member 332 from excessively pressing the belt 301i when the belt 30 is driven in the forward and reverse directions.

In Fig. 7, the state lI is the conveyor belt) 30t - Reverse feed direction (arrow B
The state lII is shown being driven in the direction). That is, a component of the driving force of the conveyor belt 30 is added to the pressing force of the first pressing roller 331, and therefore the first pressing roller 311 is slightly displaced clockwise, thereby pushing the conveying belt 30 downward. On the other hand, the pressing force of the second pressing roller 332 is reduced by a component of the driving force of the conveyor belt 30, and furthermore, the first pressing roller 331 It is rotated clockwise by the clockwise rotational effort of , and as a result, it is separated from or in light contact with the conveyor belt 30.

Next, when driving in the forward feeding direction (direction of the arrow M), in this case, the first pressing roller 331 is the conveyor belt) 30
The second pressing roller 332 rotates counterclockwise due to a component of the driving force, and the second pressing roller 332 rotates counterclockwise to come into contact with the bell 30. As a result, a component of the driving force of the dowel 30 is added to the pressing force of the second pressing roller 332, and the second pressing roller 332
is further displaced slightly counterclockwise. As a result, the second
The pressing force 0332 properly presses the document via the belt 30. Note that the first pressing roller 331 and H1iI2
The pressing force of the belt 30 by the pressing force 332 and the suppressing position can be adjusted by adjusting the length tm of the arm 350.

Effects of the present invention, in a document feeding device, the pressing force of the pressing roller that elastically presses the conveying belt from the inner surface of the conveying belt toward the upper surface of the guide member in the vicinity of the step portion of the sleeve F of the guide member is increased in the forward direction of the conveying belt. Since the load was applied to the conveyor belt from an acute angle direction,
When driving the conveyor belt in the forward direction, the conveyor belt F
The component force of the driving force of the conveyor belt reduces the pressing force of the pressing roller, and when the conveyor belt is driven in the reverse direction, the component force of the driving force of the conveyor belt is added to the pressing force of the pressing roller, and the As a result, it is possible to achieve proper and smooth document transport without putting an excessive load on the document when the document is being fed forward, and when switching back the document, the conveyance bell (conveyance bell) is moved near the shoulder section of the guide member. By closing the upper surface, it is possible to reliably prevent the rear end of the document from riding on the guide member.

In addition, if a press coat is rotatably attached via a shaft to the lower end of an arm whose upper end is pivotally supported by the frame and which forms an obtuse angle with respect to the normal transport direction (the transport belt), the transport belt can be transported in the normal transport direction. It is possible to easily configure the displacement of the pressing roller by the component force of the driving force in direction driving and reverse direction driving.In addition, one pressing roller is provided on the front side in the forward feeding direction of the conveyor belt for the pressing roller P. , if the elastic pressing force from the one pressing plate is applied to the conveying belt from an obtuse angle direction with respect to the normal feeding direction of the conveying belt, it is possible to apply the elastic pressing force to the guide member at the trailing edge of the document when switching back the document by the pressing plate. It is possible to prevent the paper from riding on the document and to share the burden of applying an appropriate pressing force to the document during forward feeding of the document by another suppression cop, thereby achieving smooth and reliable document conveyance.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of the device of the embodiment, Figs. 2 and 3 show a part of the equipment of the embodiment, and Fig. 2 is a horizontal sectional view,
Figure h3 is a front view. Figures 4 and 5. Figure 6 shows the main parts of the apparatus of the embodiment, Figures 4 and 5 are longitudinal sectional views, and Figure 6 is a horizontal sectional view. FIG. 7 is a longitudinal sectional view of the buttocks showing the second embodiment. DESCRIPTION OF SYMBOLS 1...Paper feed part, 10...Guide member, 11...Stopper crotch part, 20...ulL goggles 1...Frame, 30...Transport belt, 33...Press plate p1
34... Shaft, 35... Arm, 36... Bin, 40... Paper discharge section, 331... First pressing roller, 3
32...Second pressing core a s 841 T342...
shirt), 350...inverted V-shaped arm, 860...
pin

Claims (1)

[Scope of claims] The document is stretched so that it can be driven in the forward and reverse directions in sliding contact, and the nine originals fed from the paper feed section are driven in the forward direction to convey them from the guide member onto the document glass. , then the conveyor belt) is reversely driven in the reverse direction and stopped at the position where the trailing edge of the IIL document comes into contact with the striped flange part of the guide member. A document feeding device (2) characterized in that the pressing force that presses the upper surface of the guide member in the vicinity of the stepped portion of the guide member applies its elastic pressing force to the conveying belt from an acute angle direction with respect to the normal feeding direction of the conveying belt. ) The pressing roller is attached to the lower part of the arm whose upper end is pivotally supported by the frame and which forms an obtuse angle with respect to the normal feeding direction of the conveyor belt.
The document feeder (3) according to claim 1, which is rotatably attached to the ss via a shaft; The document feeding device according to claim 91 or 2, wherein the elastic pressing force by the one pressing force is applied to the conveying belt from an obtuse angle direction with respect to the forward direction of the conveying belt.