JPS5851865B2 - paper folding device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paper folding device applied to printers, etc., and more specifically, the present invention relates to a paper folding device applied to printers, etc. The present invention relates to a paper folding device that enables folding.

Conventionally, in this type of paper folding device, the first
The structure shown in the figure is used.

In the figure, 1 is a sheet of paper that is printed and sent out from a line printer or the like, and is sent along a guide plate 4 in the direction of an arrow 20 via a guide roller 2 and a buffer roller 3, and then fed to a folding device by a feed roller 5. Ru.

The paper 1 fed as described above is held down by the claw 1 of the claw belt 6 on one side of the folded part of the paper 1, and the other folded part of the paper 1 is held down by the ladder chain 8 in the water 7.
Guide it to the opposite side of the part and press it down to fold it.

In the above folding structure, if the distance between the ladder chain 8 and the top surface of the stacked paper is too wide,
The ladder chain 8 has little effect in pressing the paper, and if the paper 1 is thin, it will be difficult to fold it and it will not be possible to fold it correctly.

Therefore, the distance between the ladder chain and the top surface of the folded paper is usually set to be as narrow as possible.

However, with the structure of the above-mentioned conventional paper folding device, if there is a horizontal separation perforation in the middle of the paper to be folded, the folding will occur at an undesired position before the required normal folding position. In rare cases, it may fold back, preventing proper folding.

In particular, the above phenomenon tends to occur when the paper is thick.

In other words, when the paper is thick, the repulsive force against the folding of the paper is strong, and the distance between the ladder chain 8 and the top surface of the folded paper is narrow, so that both sides of the middle perforation of the paper resist the bending. It will bend due to the repulsive force.

In order to prevent the paper from bending at the intermediate perforation, it has been considered to prevent the paper from bending by changing the ratio of the cut portion and the connecting portion at the intermediate perforation, that is, by reducing the number of cut portions.

However, with the above method, there is a problem that post-processing of the paper cannot be performed correctly because the perforations deviate from the standard cut ratio.

The present invention has been made in view of the above problems, and its purpose is to automatically switch the distance between the ladder chain and the top surface of stacked sheets of paper depending on whether the sheets are thick or thin. It is an object of the present invention to provide a paper folding device that can correctly fold the above-mentioned thick paper, thin paper, paper with intermediate perforations, etc. by adjusting the paper.

The present invention has been made to achieve the above object, and includes:
The paper folding device includes a detection means for detecting the upper surface of the folded paper, and a paper table that is moved up and down based on a detection signal from the detection means. Detecting means are arranged at at least two locations at different heights on the table, and a changeover switch is provided for setting the type of paper to be placed on the paper table, and a signal from the changeover switch is used to detect the plurality of detection means. The reason is that I decided to choose one of them.

An embodiment of the present invention will be described below with reference to the drawings.

In the paper folding device shown in FIG. 1, a commonly used method is to use a photoelectric switch to detect the position of the top surface of folded and stacked sheets of paper, which blocks the light beam when the sheets are stacked. The device detects the state of
The paper table 9 on which the paper is placed is automatically lowered by a signal from the photoelectric switch.

In this embodiment, the photoelectric switches are installed at two different heights, one for thick paper and one for thin paper.

That is, the height detection photoelectric switch 10 for thin paper is installed at a higher position with respect to the paper table 9, and the photoelectric switch 11 for thick paper is installed at a lower position than the photoelectric switch for thin paper.

The heights of each of the above are determined in advance at the time of design, depending on the type of paper used, its thickness, quality, etc.

FIG. 2 is a paper table position control circuit diagram. By performing switching control between thick paper and thin paper, the paper table 9 is switched to the optimum position for thick paper or the optimum position for thin paper, and the paper is stacked. This is a control circuit that counts the overlapping state and lowers the table according to the stack of sheets.

In the figure, 10 is a paper table 9 as shown in FIG.
A photoelectric switch 11 is also placed at a lower position on the paper table 9; 14 is a thin paper/thick paper selection switch provided on the operation panel; 15. 16 is an AND circuit, 1γ is a negative circuit, 18 is an OR circuit, 19 is a counter, and 21 is a drive circuit for lowering the paper table 9.

When the paper to be handled is thin paper, the operator sets the designation switch 14 on the operation panel to the thin paper side.

A signal "1" is output from the designation switch 14, so that the AND circuit 15 is enabled and the AND circuit 16 is disabled.

As a result, the detection signal from the photoelectric switch 10 is input to the counter 19, and when a predetermined count is reached, the counter 19 outputs a lowering signal to the drive circuit 21, and the paper table 9 is lowered by a certain distance. Ru.

In addition, if the paper to be handled is thick paper, the designated switch 14
is set on the cardboard side, and as a result, the AND circuit 16 is enabled and the detection signal from the photoelectric switch 11 is accepted.

The lowering operation of the paper table is the same as that for thin paper, so the explanation will be omitted.

In this way, depending on the type of paper to be handled, the optimum distance for the paper can be secured between the ladder chain and the top surface of the paper.

Therefore, it is possible to avoid problems such as folding of the paper at undesired positions such as the middle perforation of the paper.

As described above, according to the present invention, by arbitrarily setting the designation switch according to the type of paper to be handled, it is possible to fold the paper under the optimal conditions for that paper.

In the embodiment described above, the paper types are limited to two types, but the present invention is of course not limited to this, and if there are many types of paper to be handled, only those types can be used. It is also possible to handle many types of paper by providing photoelectric switches and determining which of the photoelectric switches is to be enabled.

Further, in the above-mentioned embodiments, a photoelectric switch is used as the detection means, but various other detection means can be applied.

[Brief explanation of the drawing]

FIG. 1 is a sectional side view of the main part of the paper folding device, and FIG. 2 is a table position control circuit diagram. In the figure, 1...Paper, 2...Guide roller, 3...Buffer roller, 4...Guide plate, 5...Feed roller, 6・・・・・・
- Belt with claws, γ...Claws, 8...U. Darchen, 9...Paper table, 10...
... Photoelectric switch for thin paper, 11 ... Photoelectric switch for thick paper, 14 ... Designated switch, 15, 1
6...AND circuit, 17...Negation circuit, 18...OR circuit, 19...Counter, 20...Paper feeding direction , . . . is a drive circuit. 21...

Claims (1)

[Claims] 1. In a paper folding device comprising a detection means for detecting the upper surface of a folded paper and a paper table that is moved up and down based on a detection signal from the detection means, the height above the paper table is Detecting means are arranged at at least two different locations, and a changeover switch is provided for setting the type of paper to be placed on the paper table, and one of the plurality of detection means is selected by a signal from the changeover switch. A paper folding device characterized by: