JPH0659342U - Paper cassette - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a paper feed cassette that does not cause double feed, oblique paper feed, etc. when the number of paper sheets stacked on the pressure plate is small. [Structure] When the number of laminated papers placed on the pressure plate 3 on which the laminated papers are placed becomes small, or when a small number of laminated papers are placed on the pressure plate 3, the pressure plate 3 is rotated. A film rear end guide 15 is provided on the pressure plate 3 so that the laminated paper is pushed out toward the front wall of the corner claw along with the movement.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a sheet feeding cassette that is mounted in a sheet processing apparatus such as a printer and that stacks and stores sheets conveyed to a sheet processing unit.

[0002]

[Prior art]

 The paper feed cassette as described above is mounted on a paper processing device (hereinafter referred to as a printer) in a state where a large amount of paper is stacked and stored, and the stacked paper is printed one by one by a separation roller. It is delivered to the club.

A general configuration of a paper feed cassette mounted in a printer will be described with reference to FIG. The sheet feeding cassette 1 includes a pressure plate 3 on which sheets of the same standard are stacked and placed. A base end portion of the pressure plate 3 is rotatably supported by a frame of the sheet feeding cassette 1 by a support shaft 4, and a tip end portion of the pressure plate 3 is provided on a rear surface of the tip end portion thereof with a separating roller 7. A pressing spring 5 that urges toward is attached.

As shown in FIG. 3A, when a large number of sheets 10 of the same standard are placed on the pressure plate 3 against the biasing force of the pressing spring 5, the stacked sheets are As shown in (b), the leading edge side of the uppermost sheet is brought into contact with and biased by the separation roller 7 by the biasing force of the pressing spring 5. At this time, both ends of the uppermost sheet are in contact with the corner claws 9 provided in the sheet feeding cassette 1. Then, in this state, the separation roller 7 is driven in the direction of the arrow so that the uppermost sheet is released from the corner claws 9 and fed one by one toward the printing section.

[0005]

[Problems to be solved by the device]

 As shown in FIG. 3B, when a large number of sheets are stacked on the pressure plate 3, the stacked sheets are stably fed one by one.

However, when the stacked sheets are gradually fed out and the number of sheets becomes small, the pressure plate 3 is largely inclined around the support shaft 4 as shown in FIG. 4, and the stacked sheets are pressed by the pressure plate 3. 3 is shifted down from the cassette bottom plate 6 and its rear end comes into contact with the paper rear end guide 2. Since the leading edge of the stacked sheets of paper draws a locus about the support shaft 4 of the pressure plate 3, when the number of stacked sheets becomes small, as shown in FIG. A gap A is formed between the front wall portion 9a and the front wall portion 9a. The gap A becomes more remarkable as the number of stacked sheets of paper decreases.

FIG. 5 is an enlarged plan view of a portion of the pressure plate of the paper feeding cassette shown in FIG. 4, and shows the relationship between the paper placed on the pressure plate and the corner claws. As shown in the figure, the corner claws 9 are in the shape of right-angled triangles facing each other, and when the separation roller (not shown) is driven, the paper comes off from the oblique sides of the respective corner claws. Be paid out. Side guides 3a are provided on both sides of the pressure plate 3 with a certain clearance so as to cope with moisture absorption of a sheet to be placed, dimensional error and the like. In the figure, the clearance is shown as C when the paper is loaded along one guide and B when the paper is loaded in the center between the side guides. Further, A is a gap caused by a decrease in the number of sheets placed on the pressure plate 3 as described above.

As is clear from the figure, when the gap A becomes large, the engagement between the sheet and the corner claw 9 is eliminated or becomes extremely small. In particular, when the paper is loaded along one of the guides, the one front end of the paper is easily disengaged from the one corner claw 9. As a result, the sheets cannot be separated into one sheet, which causes double feed, skewed sheet feeding, etc.

The present invention has been made to solve the above-mentioned problems, and does not cause double feeding, oblique feeding, etc. when the number of laminated sheets on the pressure plate is small. An object is to provide a cassette for paper feeding.

[0010]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, a sheet feeding cassette of the present invention comprises a pressure plate on which laminated paper is placed, a supporting means for axially supporting a base end portion of the pressure plate so that the pressure plate rotates, and And a sheet separating section that is provided on the front end side of the pressure plate and that presses the laminated paper placed on the pressure plate against the separation roller and the corner claws to separate the laminated paper into one sheet. However, a flexible guide member is provided on the pressure plate so that the laminated paper is pushed out toward the paper separating portion side as the pressure plate rotates.

[0011]

[Action]

 Even when the number of stacked sheets placed on the pressure plate is small or the number of stacked sheets has decreased due to the paper feeding operation, there is a gap between the front side of the stacked sheets and the front wall of the corner claw. Does not occur and always maintains the engaging relationship between the paper and the corner pawl.

[0012]

【Example】

 Hereinafter, embodiments of the present invention will be specifically described with reference to the accompanying drawings. In the drawings described below, the same parts as those in the above-mentioned conventional technology are designated by the same reference numerals, and the description thereof will be simplified or omitted.

As shown in FIG. 1A, the pressure plate 3 on which sheets of the same standard are stacked and placed is rotatable by a support shaft 4 on a frame of a sheet feeding cassette (not shown). Is supported by. One side portion 15a of a film rear end guide 15 made of a flexible synthetic resin such as a polyester film or vinyl chloride is fixed to the rear surface 3a of the rear end of the pressure plate. The film rear end guide 15 is arranged along the cassette bottom plate 6 and the paper rear end guide 2 from the rear end back surface 3a of the pressure plate, and the other side portion 15b is fixed to the upper inner surface portion 2a of the paper rear end guide. ing.

FIG. 1B shows a state in which the number of stacked sheets of paper on the pressure plate 3 is small and the pressure plate 3 is rotated counterclockwise about the support shaft 4. Since the film rear end guide 15 is fixed to the rear end back surface 3a of the pressure plate, the film rear end guide 15 is pulled rightward in the drawing as the pressure plate rotates. Due to this drag amount D, the trailing edge of the laminated paper is pushed forward (right), and the above-mentioned gap between the front surface of the laminated paper and the front wall of the corner claw is eliminated. As a result, the uppermost sheet of the stacked sheets is always kept in engagement with the corner claws on both sides, and one sheet can be reliably separated.

FIGS. 2A and 2B show the overall structure of the sheet feeding cassette corresponding to FIGS. 1A and 1B, respectively. As is clear from FIG. 2B, when the number of stacked sheets of the paper 10 on the pressure plate 3 is small, the laminated paper is pushed forward by the film trailing edge guide 15, and the paper as shown in FIG. There is no gap A generated between the front surface portion and the corner front wall portion 9a.

Further, even when a large number of sheets are stacked and placed on the pressure plate 3 and the number of stacked sheets decreases and the inclination angle of the pressure plate gradually increases, the film trailing edge guide 15 is gradually pulled forward, and with this, the rear end of the laminated paper is also gradually pushed forward. Even in this case, there is no gap between the front surface of the paper and the front wall of the corner pawl, and the leading edge of the paper and the corner pawl are always engaged with each other to ensure that one sheet of paper is separated. You can

[0017]

[Effect of device]

 As described above, according to the paper feeding cassette of the present invention, even when the number of stacked sheets placed on the pressure plate is small, the engagement between the leading edge of the sheet and the corner claw is always maintained. Therefore, the separation of one sheet is accurately performed, and double feeding and skew feeding are prevented.

[Brief description of drawings]

FIG. 1 shows a sheet feeding cassette of the present invention, (a) is a partially enlarged side view showing a state where a pressure plate is not inclined, and (b) is a portion showing a state where a pressure plate is inclined. It is an expanded side view.

FIG. 2 is a side view showing the overall structure of the sheet feeding cassette of the present invention, FIG. 2 (a) shows a state in which a small number of sheets are loaded against the biasing force of a pressing spring, and FIG. Shows the state in which the paper is biased by the paper feed roller by the biasing force of the pressing spring.

FIG. 3 is a side view showing a configuration of a conventional paper feeding cassette, (a) shows a state in which a large number of papers are loaded against the biasing force of a pressing spring, and (b) shows The state in which the paper is biased by the paper feed roller by the biasing force of the pressing spring is shown.

FIG. 4 is a diagram showing a state in which the number of laminated sheets is reduced from the state shown in FIG. 3 (b).

5 is an enlarged plan view of a portion of the pressure plate shown in FIG. 4, showing a relationship between a sheet placed on the pressure plate and a corner claw.

[Explanation of symbols]

1 ... Paper feed cassette, 3 ... Pressure plate, 5 ... Pressing spring, 7 ... Separation roller, 9 ... Corner claw, 10 ... Paper,
15 ... Film rear end guide (guide member).

Claims (1)

[Scope of utility model registration request] 1. A pressure plate on which laminated paper is placed, a supporting means for axially supporting a base end portion of the pressure plate so that the pressure plate rotates, and a pressure plate provided on the tip end side of the pressure plate. A sheet feeding cassette having a sheet separating section for separating one sheet of the laminated sheet by pressing and urging the laminated sheet placed on the sheet against a separation roller and a corner claw. A paper feed cassette characterized in that a flexible guide member is provided on the pressure plate so that the laminated paper is pushed out toward the paper separating section.