JPS5916930Y2 - Copy machine document feeder - Google Patents

Description

[Detailed description of the invention] This invention relates to a document feeding device of a copying machine that carries a document to be copied onto a platen from one side of the platen using a conveyor belt, and carries it out to the other side of the platen after copying. .

Conventionally, a document feeding device for a copying machine in which a document to be copied is carried in from one side by a conveyor belt until it hits a stopper, positioned on a platen, and then carried out to the other side after copying is shown in Fig. 1. As shown in FIG.
A gap C is formed between the lower surface of the conveyor belt (a) and the upper surface of the platen b on the document import side, and by gradually decreasing this gap toward the topper d, the contact pressure of the conveyor belt (a) is reduced on the stopper d side. It is already known to increase the number sequentially.

However, with the former conveyor belt (a) that brings the entire lower surface of the document into close contact with each other, the conveyance force is too strong, and in the case of a thin and weak document e, the leading edge of the document e will bend when it comes into contact with the stopper d. Accurate positioning may become impossible, and static electricity is likely to occur due to the large contact area between conveyor belt (a) and platen b, which causes document e to come too close to conveyor belt (a) and exceed stopper (d). There was also.

In addition, in the latter case where a gap C is provided on the document input side, when the document e is a small size document e or a copied sheet with fusible oil attached, the document e is There may be cases where the leading edge of the document e does not reach the stopper d due to slipping, and to prevent this, the gap C is made as small as possible to increase the conveying force, which will cause the above-mentioned former problem, that is, the document is thin and weak. In the case of document e, the leading edge was bent or damaged.

This invention was made with the aim of eliminating such problems, and it provides a document feeding device in which the contact pressure between the conveyor belt and the platen gradually decreases on the side of the stopper that positions the document. This is intended to prevent slippery originals from becoming unfeedable and thin and weak originals from being damaged.

This invention will be described in detail below with reference to an embodiment shown in FIG.

In FIG. 3, reference numeral 1 denotes a platen (not shown) provided in a copying machine, and above this platen 1, there is a document input side located on one side of the platen 1 (on the right side of the figure) and a position on the other side of the platen 1. A drive roller 3 and a driven roller 4 are spaced apart on the document delivery side (left side in the figure), and these rollers 3,
A pair of belt holding rollers 5 and 6 are rotatably provided below 4, and an endless conveyor belt 7 is wound between these driving roller 3, driven roller 4, and belt holding rollers 5 and 6. equipped.

Of the belt press rollers 5 and 6, one belt press roller 5 located closer to the document input side is located at a slightly lower position than the other belt press roller 6, and presses a part of the conveyor belt 7 onto the top surface of the platen 1. The other belt pressing roller 6 is located at a distance from the top surface of the platen 1, and the bottom surface of the conveyor belt 7 wound between these belt pressing rollers 5 and 6 is in contact with the top surface of the platen 1. In between, a gap 8 is formed that gradually increases from the document input side to the document output side, and the distance from the belt pressing roller 5 near the document input side to a stopper 10, which will be described later, is such that the copying machine can make copies. The length of the original document 2 is set to be longer than the maximum length of the original document 2.

On the other hand, reference numeral 9 denotes a pinch roller installed on the input side of the original 2, which is used to hold the original between the transport bell l-7 and the platen 1.
10 is a stopper provided on the document delivery end side of the platen 1;
It functions to position the original document 2 carried in to a predetermined position, and after copying, it rotates so that the document 2 can pass over it.

As described above, the document feeding device of a copying machine according to this invention forms a gap 8 between the lower surface of the conveyor belt 7 and the upper surface of the platen 1, which gradually increases from the document input side to the document output side. , and a stopper 10 for positioning the original 2 is provided at the original transport side end of the platen 1, and the distance between the stopper 10 and one of the belt pressing rollers 5 provided near the original transport side is determined by the copying machine. Since the length of the original that can be copied is longer than the maximum length of the original that can be copied, a part of the conveyor belt 7 is pressed against the top surface of the platen 1 by one of the belt presser rollers 5 provided near the original input side to securely hold the original 2 on the original input side. Not only can the document 2 be fed onto the platen 1, but since the conveying force of the document 2 gradually decreases toward the document delivery side, the document 2 comes into contact with the stopper 10 after the conveying force decreases. Therefore, even if the document 2 is thin and weak, it can be reliably fed to a predetermined position without the risk of its leading edge being bent or damaged due to contact with the stopper 10. .

[Brief explanation of the drawing]

1 and 2 are explanatory diagrams showing a conventional document feeding device of a copying machine, and FIG. 3 is a schematic diagram showing a document feeding device of a copying machine which is an embodiment of this invention. 1 is a platen, 2 is a document, 3 is a drive roller, 4 is a driven roller, 5 and 6 are belt holding rollers, 7 is a conveyor belt, 8
is the gap, and 10 is the stopper.

Claims (1)

[Scope of utility model registration request] Above the platen 1 on which the original 2 to be copied is placed, a driving roller 3 and a driving roller 3 are spaced apart from each other on the original loading side located on one side of the platen 1 and the original transporting side located on the other side of the platen 1. A driven roller 4 is provided, and an endless conveyor belt 7 is wound around the driving roller 3 and the driven roller 4, and is located between the driving roller 3 and the driven roller 4, and is located near the document input side. The conveyor belt 7
One belt presser roller 5 presses a part of the platen 1 against the upper surface of the platen 1, and the platen 1 is placed near the document delivery side.
and the other belt presser roller 6 located at a higher position than the distance between the belt presser roller 5 and the one belt presser roller 5,
A gap 8 is formed between the lower surface of the conveyor belt 7, which is passed between the belt presser rollers 5 and 6, and the upper surface of the platen 1, and gradually increases from the document input side to the document output side. , a stopper 10 for positioning the original 2 is provided at the original delivery side end of the platen 1, and the stopper 1
A document feeding device for a copying machine, characterized in that the distance between the belt presser roller 5 and the one belt presser roller 5 is set longer than the maximum document length that can be copied in the copying machine.