JPH0676150B2 - Paper feeder - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding device that separates a large number of stacked single sheets one by one and sends them out by a sheet feeding roller.

2. Description of the Related Art As a paper feeding device of this type, there is a paper feeding device in which, as seen in a cassette for paper feeding, both front ends of a cut sheet of the outermost layer with which a paper feeding roller comes into contact are pressed by claws. Also, when the paper feed roller and the reverse rotation roller that is connected to the motor through the slip clutch and rotates in the direction opposite to the feed direction of the paper feed roller are opposed to each other, and a single paper cut passes between them. Slips the slip clutch and rotates the reverse rotation roller in the single-sheet feed direction by the frictional force between the single-cut sheet and the multiple-cut sheets that are fed in an overlapping manner. Keeping the slip clutch in a power transmission state by slipping other cuts, pushes back the cuts other than the one to be sent by rotation of the reverse rotation roller, and separates the cuts one by one. There is something like this.

Further, as shown in FIG. 5, a single sheet 102 is formed by a stopper 101 having a large number of steps defined by the steps of a single sheet.
There is one in which the leading edge of the sheet is pressed and the single-cut sheets 102 are separated one by one by the step of the stopper 101 and fed by the paper feed roller 103.

Problems to be Solved by the Invention However, in the case where the both ends of the cut sheet are pressed by the claws, the both ends of the cut sheet warp when they are disengaged from the claws.
In the case of a strong single-cut sheet such as a postcard, a fold line is formed, which is inappropriate. Further, the one using the reversing roller requires power and slip clutch, which makes the structure complicated and expensive. Further, the structure shown in FIG. 5 has a problem that it is difficult to form the stopper 101 and it is difficult to determine the height dimension of the step.

Means for Solving the Problems A guide surface for supporting a single-cut sheet laminated on a large number of sheets and a paper feed roller for contacting the outermost-cut sheet on the guide surface side are provided, and a stopper crossing the guide surface is provided. And a gap is formed between the end of the stopper and the guide surface to substantially match the thickness of the single sheet, and the stopper is gradually formed on one surface of the stopper as it approaches the guide surface. An inclined surface that is inclined toward the feeding direction of the slip is formed, and a sliding surface having a low friction coefficient with which the leading edge of one sheet supported by the guide surface contacts the inclined surface and a large friction coefficient. A resistance surface and an alignment surface having a small friction coefficient with which the leading edge of the cut sheet abuts are sequentially formed in a direction away from the guide surface.

Therefore, when feeding the cut sheet along the guide surface by the paper feed roller, the leading edge of the cut sheet is aligned by the alignment surface, and the resistance surface prevents the cut sheet from advancing, and it is one of the outermost layers on the guide surface side. Only one piece of the slip is brought into contact with the planing surface to make it slide.

Embodiment An embodiment of the present invention will be described with reference to FIGS. 1 to 4. As shown in FIG. 4, inside the main body 1, there are a rotating photosensitive member 2, a charging charger 3 forming a charging layer on the outer periphery of the photosensitive member 2, and a charging layer formed by the charging charger 3. An exposure unit 4 that scans a laser beam to form an electrostatic latent image, and a developing device 5 that develops the electrostatic latent image.
Then, the transfer charger 12 for transferring the developed image from the first cassette case 6 to the cut sheet 11 sent by the paper feed roller 7 and the feed rollers 8, 9 and 10, and fixing the cut sheet 11 after the transfer And a fixing roller 13 that operates. The single-cut sheet 11 of the first cassette case 6 is curved into a U-shape by the guide plate 14 and is supplied to the transfer charger 12.

A second cassette case 15 is detachably attached to the front surface of the main body 1. This second cassette case 15
As shown in FIG. 1, there is a curved surface 16 that conveys the single-cut sheet 11 with the guide plate 14, and the ends of the curved surface 16 are formed on both sides of the guide plate 14. A locking projection 17 that is detachably engaged with a stop hole (not shown) is formed. Curved surface 16
A plurality of openings 18 are arranged in the left-right direction in the
A pinch roller 19 that contacts the feed roller 8 is provided inward of 18 and is rotatably provided by being biased in one direction by a plate spring 20.

And in the second cassette case 15, a postcard that is a single slip
The guide surfaces 22 and 23 that support 21 are bulged, and a paper feed roller 24 that comes into contact with the outermost cut sheet 21 on the guide surfaces 22 and 23 side is rotatably provided. This paper feed roller 24
A pair of left and right eccentric cams 25 and a gear 26 are fixed to the shaft portion 24a, and a motor 28 for driving a gear 27 meshed with the gear 26 is attached to the second cassette case 15. In the second cassette case 15, a pair of left and right swing arms 30 that rotatably hold both ends of the push-up roller 29 and contact the eccentric cam 25, a cover 31 that covers the postcard 21, and a top-level postcard. twenty one
And a plate 33 having a weight 32 for pressing. Both sides of the cover 31 are rotatably held by pins 45 erected on the cassette case 15, and both ends of the plate 33 are rotatably held in holes 34 formed in the cover 31.

Further, as shown in an enlarged view in FIG. 2, a gap corresponding to the thickness of one postcard 21 is formed between the inner surface of the cover 31 and the guide surface 22.
Stopper 36 is fixed by opening 35. This stop
On one surface of 36, an inclined surface 37 is formed which gradually inclines with a curved surface toward the feed direction (left side) of the postcard 21 as it goes from the topmost postcard 21 to the guide surface 22, and this inclined surface 37, One of the lowermost postcards 21 on the guide surface 22 side has a sliding surface 38 with a low friction coefficient that comes into contact with the leading edge, a resistance surface 39 with a large friction coefficient due to a sponge, etc., and a friction coefficient with which the leading edge of the postcard 21 abuts. And the alignment surface 40 having a small size are sequentially arranged in the direction away from the guide surface 22. Furthermore, the guide surface 22
A gate 42 having a gap slightly larger than the thickness of one postcard 21 is formed at the lower end of the projecting portion 41 projecting from both sides.

Further, as shown in FIG. 3, a support piece 43 for rotatably supporting a pin 30a protruding from the end of the swing arm 30 and a support piece for rotatably supporting the shaft portion 24a of the paper feed roller 24. 44 is integrally formed with the second cassette case 15. Further, a pin 45 for rotatably holding the cover 31 is erected on the outer side of the protrusion 41.

In such a configuration, the single-cut sheet 11 of the first cassette case 6 is pulled out by the paper feed roller 7, and the feed rollers 8, 9, 10
Is supplied to the photoconductor 2 to print. When printing on the postcard 21, the paper is fed by rotating the paper feed roller 24 by the motor 28. That is, the lowermost postcard 21 is sent to the left by the paper feed roller 24 under the pressure of the weight 32. At this time, the tips of the postcards 21 in the upper layer gradually move downward while being aligned by the alignment surface 40. Even if both ends of the postcard 21 are broken, the postcard 21 is corrected straight in a process of gradually moving forward along the alignment surface 40. The postcard 21 abutting against the resistance surface 39 does not easily slip on the resistance surface 39 having a large frictional resistance, so that the postcard 21 stagnates and the separating action for the postcard 21 in the lowermost layer is surely performed. In this way, the postcard 21 of the second cassette case 15 is sent to the main body 1. Further, the paper feed roller 24 makes one rotation to feed one postcard 21 and then stops, but the cam 25 moves to the hypert in the latter half half rotation from the time when the tip of the postcard 21 reaches the feed roller 9 in the main body 1. Hold and push up the swing arm 30. As a result, the roller 29 pushes up the postcard 21 and separates it from the paper feed roller 24, and the subsequent operation of sending the postcard 21 is left to the feed rollers 9 and 10 on the main body 1 side.

Further, when the postcard 21 is replenished in the second cassette case 15, the cover 31 is opened upward with the pin 45 as a fulcrum. At this time, since the plate 33 follows the cover 31 and is suspended in the hole 34 over the vertical surface, the postcard 21 can be stacked on the guide surfaces 22 and 23 without being obstructed by the weight 32.

EFFECTS OF THE INVENTION Since the present invention is configured as described above, when the sheet is fed along the guide surface by the feed roller, the leading end of the sheet is aligned by the alignment surface and the advance of the sheet is blocked by the resistance surface. Only the single sheet of the outermost layer on the guide surface side can be brought into contact with the sliding surface for sliding, and therefore even the single sheet with strong stiffness can be reliably separated one by one. This has the effect of simplifying the structure for separating votes.

[Brief description of drawings]

1 to 4 show an embodiment of the present invention. FIG. 1 is a vertical sectional side view of an essential part, FIG. 2 is a vertical sectional side view showing an enlarged structure of a stopper, and FIG. Fig. 4 is an exploded perspective view showing the shape of the guide surface and the support structure of the paper feed roller, Fig. 4 is a vertical sectional side view showing the entire structure in a reduced scale, and Fig. 5 is a vertical sectional side view showing a conventional single-sheet separating means. is there. 21 …… Postcard (single sheet), 22,23 …… Guide surface, 24 …… Feeding roller, 35 …… Gap, 36 …… Stopper, 37 …… Inclined surface, 38
…… Sliding surface, 39 …… Resistance surface, 40 …… Alignment surface

Claims (1)

[Claims] 1. A guide surface for supporting a plurality of cut sheets and a paper feed roller which comes into contact with the outermost cut sheet on the guide surface side are provided, and a stopper crossing the guide surface is provided. A gap is formed between the end of the stopper and the guide surface so as to substantially match the thickness of the single sheet, and the sheet is gradually fed to the one surface of the stopper as it goes toward the guide surface. Form an inclined surface that inclines toward the direction, and on this inclined surface,
A sliding surface having a low friction coefficient with which the leading edge of one of the cut sheets supported by the guide surface comes into contact, a resistance surface with a large friction coefficient, and an aligned surface with a small friction coefficient with which the leading edge of the cutting sheet abuts. The sheet feeding device is formed by sequentially arranging the sheets in a direction away from the guide surface.