JPH0395031A - Sheet material feeding device - Google Patents

Abstract

PURPOSE:To prevent an up-warp in the tip of sheet material and thereby its defective feeding by providing a recessed part at a tip regulating member in such a way that a part of the tip of the sheet material is brought into contact with this tip regulating member. CONSTITUTION:Sheet material S loaded on a loading base 43 are fed from the sheet material S in the lowest position by the feeding action of a feeding means, and the uppermost surface of the sheet material S descends gradually by the pressing of a pressing member 5. A recessed part 7b is provided at a tip regulating member 7 for regulating the tip of the sheet material S. Accordingly, friction between the tip of the sheet material S and the tip regulating member 7 at the time of descent by the feeding of the sheet material S becomes small, so that an up warp in the tip of the sheet material at its descending time is dissolved, and the sheet material is thereby prevented from defective feeding.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention relates to a sheet material feeding device for an image forming apparatus such as an electrophotographic copying machine or a laser beam printer. Concerning improvement of a tip regulating member that regulates and aligns the tip. (0) Conventional technology Conventionally, image forming apparatuses such as electrophotographic copying machines have been equipped with a paper feeding device for automatically feeding sheet materials made of thick paper such as envelopes placed on a loading table into the apparatus. The paper feeding device is detachably attached to the image forming device as a unit.

The leading ends of the sheet materials loaded on the loading table are regulated and aligned by a leading end regulating member, and the sheets are separated one by one from the lowest side and fed into an image forming device or apparatus by a feeding means. During this feeding, the upper part of the sheet material is pressed against the feeding means by the pressing means.

An example of a conventional sheet material feeding device of this type is shown in FIGS. 8 to 1.
This will be explained based on Figure 0.

In the figure, the paper feeding device 1 has a pair of positioning members 40 at its front end (left end in FIG. 8).
By inserting and removing the positioning member 40 into a mounting hole provided on the upper side of the main body 3 of the laser beam printer 2, the paper feeding device 1 can be attached to and removed from the laser beam printer 2. A cassette 41 that is detachably attached to the laser beam printer 2 is disposed below the paper feeding device 1, and this cassette 41 is used to stack ordinary sheets. Furthermore, above the cassette 41 on the side surface of the laser beam printer 2, a manual feed port 3a is provided for inserting a manual sheet.

The sheet material S fed from the sheet material feeding device 1 as described later is conveyed into the laser beam printer 2 through the manual feeding port 3a. The main body 42 of the paper feeding device 1 has a loading table 43 for loading sheet materials S, and this loading table 43 includes a regulating plate 45a that restricts movement of the sheet materials S in the width direction; 4
5b is arranged. A pair of racks 46. below the regulating plates 45a, 45b are provided along the width direction of the loading platform 43.
47 is arranged so as to be slidable, and this rack 46
．． 47 are each engaged with a pinion 49 rotatably disposed on the back side of the loading table 43. As a result, the racks 46, 47 and the L-shaped regulating plate 45 integrated therewith.
a and 45b are adapted to move and hang in the width direction in conjunction with each other.

On the loading table 43, a detection lever 50 for detecting the presence or absence of the sheet material S is supported by a shaft 51, and its lower end is connected to a photointerrupter 52 provided on the back side of the loading table 43.
Go back and forth inside to turn this on/on. When there is no sheet material S on the loading platform 43, the upper end of the detection lever 50 rotates in a direction that projects toward the upper surface side of the loading platform 43, thereby detecting the absence of the sheet material S. The mounting table 43 is provided with an escape hole 43a to avoid interference with the detection layer 50 of the sheet material detection device 53. Note that the sheet material S is made of, for example, a cardboard-like material such as an envelope.

On the downstream side of the photo interrupter 52, a loading platform 43 is provided.
A feeding roller (feeding means) 55 for feeding the sheet material S stacked on the sheet material S from below is rotatably disposed.

A weight (pressing member) 56 is arranged above the feeding roller 55, and a protrusion formed on both ends of the weight 56 is used to push the main body 4.
It is made vertically movable by being loosely engaged with a pair of guide grooves 57 (see Fig. 9) provided in 2. This weight 56 acts to press the sheet material S against the feeding roller 55, and a cutout 56a is formed on the lower surface of the weight 56 to avoid interference with the detection lever 50. ing. Further, on the bottom surface of the weight 56, an appropriate I! i
1!1l! A double-feed prevention sheet 35 having a coefficient and for preventing double-feeding of sheet materials S is provided. Attachment member 5 fixedly installed on the downstream side of the weight 56
9 is provided with a tip regulating member 60 for aligning and regulating the tip of the sheet material S on the loading table 43, and the lower end thereof and the front end of the loading table 43 are separated by a predetermined distance. The sheet material S is fed and hung from this space. A separation plate 62 (hereinafter referred to as separation pad) made of a high-friction material is attached to a mounting base 61 fixed to the lower surface side of the mounting member 59.
It is inclined at an appropriate angle with respect to the feeding direction of the sheet material S fed from. A flexible elastic member 63 is fixed at a position facing the separation pad 62,
The sheet material S fed from the feeding roller 55 is pressed against the separation pad 62 to prevent double feeding of the sheet material S.

On the downstream side of the separation bat 62, a pair of conveyance guides 65, 66 and a conveyance roller 67 for guiding the sheet material S are disposed, respectively. It is pressed and biased by. A microswitch 71 is fixed to a bracket 7o fixed to the upper part of the conveyance guides 65, 66.

Furthermore, a detection lever 72 for detecting the set state of the paper feeder 1 with respect to the laser beam printer 2 is pivotally attached to the bracket 70 with a step screw 73, and this detection lever 72 has both ends connected to the bracket 70 and the detection lever. The resiliency of torsion springs 75 fixed to and 72 respectively provides a counterclockwise rotational behavior in FIG. When attaching the paper feeder 1, the detection lever 72 is pressed by the main body 3 and rotates clockwise in FIG. The switch 71 is turned on to detect attachment of the paper feeder 1.

Next, the drive system in the sheet material feeding device will be explained with reference to FIGS. 9 and 10.

In the figure, the paper feeder 1 has a pair of side plates 76 and 77, and a guide groove 57 that guides the aforementioned weight 56.
are formed on these side plates 76 and 77, respectively. A board 79 is fixed to the outer surface of the side plate 76 via a plurality of supports. It sends and receives signals between the two. The other side plate 77 has a paper feeder 1 and a laser beam printer 2.
One end of a cable 81 is connected to the main body 3 of the . A solenoid 83 for controlling a spring clutch, which will be described later, is fixed to a bracket 82 fixed to the side plate 76.
It also serves as a grounding plate for grounding via a metal bearing 86 supporting 5.

As shown in FIG. 10, a relay gear 89 integrated with a relay gear 89a is pivotally supported by a shaft 90 on a support plate 87 fixed to the side plate 76 at an appropriate interval. , meshes with a gear 91 fixed to the output shaft 80a of the drive motor 80. Furthermore, the support plate 8
7 includes relay gears 92 and 9 that mesh with the relay gear 89.
3!1 is pivotally supported by a shaft 94, and a relay gear 95 meshing with the relay gear 89a is pivotally supported by a shaft 96. The support plate 87 is connected to the bracket 8 via a shaft 94.
Therefore, by dropping the bracket 82 to the ground, the shaft 55a of the feeding roller 55 and the shaft 67a of the conveying roller 67 also fall to the ground.

The relay gear 92 meshing with the relay gear 89 is connected to the relay gear 93 via a clutch section 85 having a generally known spring clutch, and the clutch section 85 is turned on by on/off control of the solenoid 83. /off to turn on/off transmission of driving force between both gears 92 and 93.

The gear 93 meshes with a gear 97 fixed to a shaft 55a that is integral with the feed roller 55 (see FIG. 8).

Further, a gear 99 mounted on a shaft 67a to which the conveyance roller 67 is fixed is engaged with the relay gear 95. A one-way clutch (not shown) is interposed between the shaft 67a and the gear 99, and in FIG.
When the gear 99 rotates counterclockwise, the shaft 67a also rotates in the same direction, and when the gear 99 rotates clockwise, the shaft 67a rotates in the same direction.
is now idling.

A torsion spring 101 is attached to the dowel 100 fixed to the side plate 76, and both ends of the torsion spring 101 are respectively locked to a shaft 69a and a shaft 96, which are integrated with the pinch roller 69. The roller 69 is in pressure contact with the conveying roller 67. In FIG. 9, the reference numeral 102 is
It is a connection member that establishes electrical continuity with the conveyance roller 67 via the metal bearing 103 that supports the conveyance roller 67,
This connecting member 102 has its base fixed to the side plate 76,
and its free end is screwed to the shaft 96,
It also serves as the cover for Gya99.

In the above structure, the main body 3 of the laser beam printer 2
When the drive motor 80 is rotated by a paper feed signal from the paper feed signal, the conveyance roller 67 starts rotating via the above-mentioned gear train. Solenoid 8 is activated after a predetermined time T1 has elapsed since the paper feed signal was generated.
3 is turned on, the feeding roller 55 rotates and starts feeding the sheet material S such as an envelope.

The solenoid 83 is turned off after a predetermined time T 2 ,==, and the drive transmission to the feeding roller 55 is cut off. At this time, the rear end of the sheet material S rests on the feeding roller 55, but its leading edge has reached the feeding roller 67.
As a result, the sheet material S is sent by the conveyance roller 67, and the conveyance roller 67 is driven to rotate by the action of the one-way clutch. The sheet material S fed from the paper feeding device 1 is sent into the main body 3 by a feeding roller 105 of the laser beam printer 2 shown in FIG. Further, the sheet material S fed from the manual feed port 3a of the laser beam printer 2 is detected by the paper detection sensor 106 shown in
The paper detection sensor 106 is activated in the same sequence as the manual feed mode.
After reaching this point, the paper is sent by the feeding roller 105 into the main body 3 of the laser beam printer 2, where it is printed and then discharged.

Next, the operation in which the sheet material S is separated and fed out will be explained with reference to FIGS. 12 and 13. The sheet material S stacked on the loading platform 43 with its leading edge aligned by abutting the leading end regulating member 60 is rotated in the direction of the arrow by the pressing force of the weight 56 and the feeding roller 55.
The sheets are unrolled in sequence starting from the lowest sheet material Sa. At that time, the next sheet material Sb. Sc etc. are dragged by the sheet material Sa due to the frictional force between the sheets, but the leading edge is held down by the separation pad 62 with a high friction coefficient, so that the sheet material receives the feeding force directly from the feeding roller 55. Only Sa overcomes the frictional resistance of the separation pad 62 and advances, and as shown in FIG.
It is fed beyond a.

In the figure, the elastic member 63 is made of a flexible thin plate piece, and its base is fixed to a support plate 107. When the sheet material Sa is fed, the tip of the elastic member 63 bends in the feeding direction as shown in the figure, and the reaction force causes the sheet material Sa,
The tips of Sb, Sc, etc. are lifted to the upper separation pad 62 to assist in separation.

The lowest sheet material Sa beyond the tip 62a of the separation pad 62 is guided by the conveyance guides 65 and 66 and is conveyed between the conveyance roller 67 and the vinch roller 69.

Similar operations are repeated for the next sheet materials Sb and Sc to separate and feed them.

(c) Problems to be Solved by the Invention However, in the conventional sheet material feeding device described above, the sheet materials S are fed one by one by the feeding roller 55 from the lowest side. Due to the pressing action of the weight 56, the stack of sheet materials S is lowered by the thickness of the fed sheet materials S. When the loaded bundle of sheet materials S descends with the leading edge of the sheet material S hitting the leading edge regulating member 60, as shown in FIG. , the leading edge of the sheet material S is not properly lowered, and the leading edge of the sheet material S is warped upward.

If the feeding continues with the leading edge of the sheet material S curled up in this manner, when the remaining sheet material S on the loading table 43 becomes small, the separating bat 6 will move as shown in FIG.
In the second part, there was a problem in that the leading edge of the sheet material S was bent in a V-shape, causing paper feeding failure.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a sheet material feeding device that eliminates paper feeding defects by improving the leading edge regulating member that regulates the leading edge of sheet materials loaded on a loading table. It is something.

(2) Means for solving the problem The present invention was made in view of the above-mentioned circumstances, and includes:
For example, referring to FIGS. 1 and 2, the loading platform (43
) loaded on the sheet material (S) and this sheet material (S)
A feeding means (55) that feeds out the sheet material (S) by coming into contact with the lowest sheet material (S), and a feeding means (55) that aligns the leading edge of the sheet material (S) loaded on the loading table (43). a tip regulating member (7) disposed on the downstream side of the feeding means (55); and a pressing member (5) for pushing the loaded sheet material (S) toward the feeding means (55). ), in which a part of the leading end of the sheet material (S) is connected to the leading end regulating member (
A recess (
7b).

(E) Effect Based on the above structure, the sheet material (S) stacked on the loading table (43) is fed from the lowest sheet material (S) by the feeding action of the feeding means (55>). The uppermost surface of the sheet material (S) is gradually lowered by being pressed by the pressing member (5).The tip regulating member (7) for regulating the tip of the sheet material (S) is provided with four parts (7b). As a result, the friction between the tip of the sheet material (S) and the tip regulating member (7) during the above-mentioned descent due to feeding of the sheet material (S) is reduced, and the friction between the tip of the sheet material (S) and the tip regulating member (7) is reduced. The curling up of the leading edge of the sheet material (S) is eliminated, and poor paper feeding of the sheet material (S) is prevented.

Furthermore, by providing the above-mentioned four parts (7b) on the tip regulating member (7), it can be used as a part for inserting the user's finger when handling the pressing member (5), and the pressing member (5) can be It becomes possible to bring the sheet material (S) closer to the leading edge regulating member (7), and the bouncing of the leading edge of the sheet material (S) is further reduced, thereby further preventing paper feeding failures.

Note that the above reference numerals in brackets are shown for reference to the drawings and do not limit the structure of the present invention in any way.

(F) Example A first example of the present invention will be described below with reference to FIGS. 1 to 3. Components that are the same as those shown in FIGS. 8 to 10 are designated by the same reference numerals, and their explanations will be omitted.

In FIGS. 2 and 3, a plurality of sheet materials S stacked on a loading table 43 are pressed against a feeding roller (feeding means) 55 by a weight (pressing member) 5. The tip of the loaded sheet material S is aligned with the alignment surface 7 of the tip regulating member 7.
It abuts and is aligned with a. Note that a cutout 5a is provided at the bottom of the weight 5 to avoid interference with the detection lever 50.
is taking shape.

A recess 7b is formed in the alignment surface 7a of the tip regulating member 7, as shown in FIGS. 1 and 3.

As a result, the frictional force between the alignment surface 7a and the tip of the sheet material S that is in contact with the alignment surface 7a is smaller than in the case where the recess 7b is not provided.

Here, when the feeding roller 55 rotates, the lowest sheet materials S of the bundle of sheet materials S loaded on the loading table 43 are fed one by one from the loading table 43, and the sheet materials S are Each time the sheet material S is fed, the uppermost surface of the sheet material S is pressed by the weight 5 and lowered by the thickness thereof. When the sheet material S is lowered, the frictional force that the tip of the sheet material S receives from the alignment surface 7a of the tip regulating member 7 is small as described above.
The curling of the leading edge of the sheet material S is eliminated, and the occurrence of paper feeding failures due to the curling of the leading edge of the sheet material S is prevented.

In addition, when handling the weight 5 for loading sheet materials S on the loading table 43 or for attaching and detaching during maintenance, a recess 7b into which the user's finger can be inserted is provided in the tip regulating member 7. Therefore, the weight 5 can be disposed close to the tip regulating member 7 side. Due to the proximity of the weight 5 to the tip regulating member 7 side, the curling of the tip of the sheet material S due to the above-mentioned descent is further suppressed, and the occurrence of paper feeding failure of the sheet material S due to the curling is more reliably prevented. ing. Furthermore, since the user's finger can be inserted into the recess 7b provided in the tip regulating member 7, it becomes a space when lifting the weight 5, making it easier to handle the weight 5. There is.

4 and 5 show the weight 5 in the first embodiment.
A modified example is shown.

In this sheet material feeding device 1, a pair of convex portions 5b are formed on the side of the tip regulating member 7 of the weight 5, and the convex portions 5b are formed in the concave portion of the tip regulating member 7 as shown in FIG. It protrudes into 7b. By configuring the weight 5 as described above, the convex portion 5b can reliably press down on the leading end of the sheet material S when the sheet material S is being fed. Warping can be prevented. Although the weight 5 shown in FIG. 4 is provided with two protrusions 5b, one or more protrusions 5b may be provided.

6 and 7 respectively show a second embodiment of the invention.

The tip regulating member 7A shown in the figure has recesses 7b formed on both sides of its matching surface 7a. Further, the weight 5A that presses the sheet material S loaded on the loading table 43 has a recess 5C that opens toward the tip regulating member 7, and the downstream side (
As shown in FIG. 7, the end of the tip regulating member 7 side)
It is in a state of protruding into b. By forming the weight 5A into a concave shape as described above, the alignment surface 7a of the tip regulating member 7
A space into which a user's finger can be inserted is formed between the recess 5C of the weight 5A and the recess 5C of the weight 5A.

As described above, by forming a pair of recesses 7b in the alignment surface 7a of the tip regulating member 7 and reducing the range of contact between the alignment surface 7a and the sheet material S, the sheet material can be seated similarly to the first embodiment. When the sheet material S is lowered by being fed, the leading edge of the sheet material S is prevented from curling up and the sheet material S is not fed properly due to this. Furthermore, since the downstream end of the heavy fi5A protrudes into the recess 7b of the tip regulating member 7, that is, it protrudes further downstream than the tip of the sheet material S, the sheet material S to be fed is It is more reliable to hold the sheet material S, and the prevention of the leading edge of the sheet material S from curling up due to the above-mentioned lowering and the failure of the sheet material S to be fed is further improved. Further, by utilizing the space formed between the alignment surface 7a of the tip regulating member 7 and the weight 5A, handling such as lifting of the weight 5A when loading the sheet materials S can be easily performed.

(g) Effects of the invention As explained above, according to the present invention, the loading platform (43)
A recess (7b) is provided in the regulating member (7) that regulates the tip of the upper sheet material (S) so that a part of the tip of the sheet mound (S) comes into contact with the tip regulating member (7). As a result, the frictional force between the tip regulating member (7) and the sheet material (S) is reduced, and the tip of the sheet material (S) is warped when the sheet material (S) is lowered by feeding. It is possible to prevent paper feeding failures of the sheet material S due to the upward movement.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a tip regulating member portion of a sheet material feeding device according to an embodiment of the present invention, and FIG. 2 is a vertical sectional side view showing an example of a sheet material feeding device to which the present invention is applied. , 3rd
4 is a perspective view showing the tip regulating member portion of the sheet material S to which a modified example of the weight (pressing member) is applied, FIG. 5 is a vertical side view, and FIG. 6 is a main view. FIG. 7 is a perspective view of a tip regulating member portion showing a second embodiment of the invention; FIG. 7 is a plan view; FIG. 8 is a vertical side view showing an example of a conventional sheet material feeding device; FIG. A plan view, FIG. 10 is a side view showing the drive unit, FIG. 11 is a vertical side view showing the coupled state of the material feeding device to the sea 1 and the image forming device, and FIGS. 12 and 13 are the same. The action diagrams, FIGS. 14 and 15 are action diagrams showing the sheet feeding failure state. FIG. 1 S... Sheet material 1... Sheet material feeding device 2
...Image-forming device (laser beam printer)
5, Weight 5A... Weight (pressing member), 7... Tip regulating member 7a... Matching surface 7b, 7c... Recessed part
, 43... Loading table 55... Feeding roller (feeding means) Fig. 4 Fig. 6 Fig. 5 Fig. 7 Fig. 7 67 Fig. 12 Fig. 14 b7 Fig. 13 Fig. 15

Claims (1)

[Scope of Claims] 1. A sheet material loaded on a loading table, a feeding means for feeding out the sheet material by contacting the lowest sheet material of the sheet material, and a sheet material loaded on the loading table. A sheet material feeding device comprising: a leading end regulating member for aligning the leading ends and disposed on the downstream side of the feeding means; and a pressing member for pressing the stacked sheet materials against the feeding means; A sheet material feeding device characterized in that the tip regulating member is provided with a recess so that a portion of the tip of the material comes into contact with the tip regulating member.