JP3143151B2 - Paper separation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper separating apparatus suitable for separating two sheets of paper, and more particularly to a paper separating apparatus suitable for separating paper in a diazo type copying machine.

[0002]

2. Description of the Related Art In a paper separating apparatus of a diazo type copying machine,
In a diazo type copying machine, the base paper and the photosensitive paper are brought into close contact with each other and irradiated with light, and then the base paper and the photosensitive paper are separated. At that time, the suction force of air is used.

For example, as a separating means, two suction cylinders having a plurality of suction holes arranged side by side in the horizontal direction perpendicular to the paper transport direction are arranged so that the suction holes of each suction tube face each other. By sucking air from each of the suction holes and sending one of the two sheets of paper sent from the upstream side one by one to the suction cylinder and the other to the other suction cylinder, the two sheets are sent. There is a paper separating device that separates sheets of paper.

[0004] Air suction fans are installed on both sides of a copying machine, and separation is performed by negative pressure caused by suction of the fans.

[0005]

Depending on the shape of the suction hole, since the suction is performed with a large force in the separation section, the feeding is not smooth, and the paper is kinked in the conveyance section, and the kinking in the conveyance section is caused. There is a problem that if the suction force is adjusted so as not to cause the separation, the separation will be insufficient.

When large paper is used, no problem occurs because the paper uniformly closes the holes and is separated and transported by the negative pressure of the suction force. However, in the case of small paper, At both ends near the fan, the paper does not reach that much, so the hole is not blocked. For this reason, air is freely sucked into the holes on both sides, so that the negative pressure at the central portion is reduced and the separation capacity is reduced. In this case, the paper may not be properly separated, and sometimes the paper may be discharged in a state where the two sheets are in close contact with each other. Therefore, the present invention provides a paper separating apparatus that does not cause kinking of paper in a transport unit after separation while sufficiently performing separation.
It is another object of the present invention to provide a paper separating apparatus capable of performing reliable separation regardless of the size of paper.

[0007]

In order to achieve the above object, according to the present invention, two suction cylinders having a plurality of suction holes arranged side by side in a horizontal direction perpendicular to the paper conveying direction are provided. Are arranged so that the suction holes are opposed to each other, air is sucked from each of the suction holes, one of the two sheets of paper sent from the upstream in an overlapping manner is placed in one suction cylinder, and the other is placed in the other one. In a paper separating apparatus that separates two sheets of paper by sucking and sending the suction paper to each suction cylinder, the suction holes are substantially in a tadpole shape or a combination of a large hole and at least one small hole.
And if it is in the shape of a tadpole,
Part toward the upstream side in the paper transport direction, and the tail part toward the downstream side.
In the case of a combination of the large hole and the small hole, the large hole
As the upstream side of the sheet conveyance direction, wherein by positioning slightly inward from <br/> standard paper placed downstream pores plurality juxtaposed, away from the center on the lateral, the suction The area of the holes was set small. Also, as the distance from the center on the lateral can be the position of the suction hole on the upstream side.

[0008]

[0009]

[0010]

According to the first and second aspects, a large suction force is applied to the paper at the separation section, and a small suction force suitable for conveyance is applied to the paper at the conveyance section. In the first aspect, a substantially constant suction force acts on each suction hole.

[0011]

EXAMPLE 1 In FIG. 1, as a means for separating the base paper G and the photosensitive paper K, a suction cylinder 1 on the photosensitive paper side and a suction cylinder 2 on the base paper side are provided to face each other. Lateral direction 3 orthogonal to paper transport direction 3Y
The surface of each suction cylinder viewed from X is formed of a curved surface having a substantially x shape, and is closest to the separation portion.

Air is sucked from both ends of each suction tube in the horizontal direction by a fan, and the air flows in through the suction holes 4 in response to the suction. Here, as shown in FIG. 2 (a) for the photosensitive paper side and FIG. 2 (b) for the base paper side, the shape of the suction hole 4 is slightly different depending on the suction cylinder, but is substantially tadpole-shaped. Alternatively, it can be composed of a large hole and a round small hole (see FIG. 6). And the head 4H is located upstream in the paper transport direction,
The tail 4T is formed toward the downstream side. The head 4H corresponding to the separating unit is large, and the width of the conveying unit corresponding to the next tail is small and long.

As shown in FIG. 3, the suction holes 4 are located inside each standard paper according to the size of the standard paper, and are equally divided left and right from a horizontal center line CL. An array is formed.

As described above, as shown in FIG. 4, in the separating section 5 for separating two closely adhered papers, since the area of the hole is large, the suction force at the location indicated by the negative pressure × the area is also increased and the separation is performed. Is performed reliably. On the other hand, in the transport section 6, the area of the hole is small, so that the paper is not kinked and is uniformly held.

In FIG. 2, the suction holes 4 on the base paper side are used.
(See FIG. 2B)) is the suction hole 4 on the photosensitive paper side (FIG. 2B).
(See (a)) slightly upstream (specifically, about 1 m)
The reason for positioning m) is to prevent the photosensitive paper from being transported to the base paper side and reaching the developing solution to be fed to the base paper even if the separation failure occurs, thereby preventing the base paper from being damaged.

As described above, even if a suction hole is set or a suction hole having the same shape and size is simply arranged, separation of small-sized paper becomes insufficient. In the following example, in order to avoid such non-separation, regardless of the size of the standard paper, regardless of the type of paper used, the suction holes should be slightly inside the both ends of the paper. The position is determined, and the distribution of the suction force due to the negative pressure given by the fan is kept constant regardless of the distance from the fan.

The size of the hole is such that the suction force is increased by 10 to 20% at the central portion CL corresponding to the central portion in the horizontal direction for a small-sized paper. If you do this,
Since the inflow of air on both sides of the suction cylinder has a smaller area than that of the central part, it is small and it is possible to reduce pressure loss. The fan does not need to be on both sides, and if the suction by pressure is sufficient, furthermore, if such a design is performed well, one fan is attached to one side, and the size of the suction hole is determined in time .

The size of the suction hole is determined as follows. In general, a negative pressure is applied to the pressure distribution in the tube by closing one side and suctioning the other. If there is some inflow in the length direction of the tube, the following expression is obtained. P = AX ² + BX + C (1) In equation (1), X is the distance from the closed end and is normalized by the length of the tube. In the case of a diazo type copier, since there are fans at both ends, X = 0 at the center and X = 1 at the point where the fan is connected.
, And the pressure is lower at the central portion where X is smaller. Experimentally, A and C are about the same, and B is about 1
/ 30. Therefore, if the area S (X) of the place can be determined so that P × S = constant,
The paper can be sucked at any location with a uniform negative pressure.

Further, to increase the central portion by 10 to 20%, it is sufficient to set P-DX = AX ² + BX + C (2), where D is (0.1 to 0.2) × P. In other words, the P (1-EX) = AX 2 + BX + C (E = 0.1~0.2) ... (3). Here, E is a constant that determines the ratio of increasing the pressure at the center.

As a specific example in which these facts are actually adapted, a diazo type copying machine having fans on both sides which can use A1 size paper will be described. The distance between the fans at both ends is about 70 cm, the total length of the tube is 68 cm, and X is 3
When normalized at 0 cm, the value of X corresponding to the paper standard is as shown in Table 1.

[0021]

[Table 1]

[0022]

[Table 2]

The area of the hole with respect to each standard paper is obtained from the equations (1) and (3) for X. This is divided into a head and a tail, and the width is determined by setting the base paper side to 1: 1 and the photosensitive paper side to 1: 2.

Table 2 shows the values obtained by the equation (1) in which the pressure is kept constant. here,
Although the width is shown in the table, the length in the traveling direction of the paper is constant at the head and tail of the base paper and the photosensitive paper, respectively. Note that, in this calculation example, the pressure is made constant. However, in order to increase the pressure in the central portion, a similar calculation is performed using the equation (3).

In actual production, if the width of the central portion, the intermediate portion, and the end portion is set to be about three steps in view of the standard of work, etc., it can withstand use. Done.

The advantages of this embodiment are as follows. Generally, both the base paper and the photosensitive paper are standard papers. Therefore, by determining the suction holes corresponding to the standard papers, paper separation can be performed efficiently and energy can be saved. Also, even when small paper is used for a large machine, the base paper and the photosensitive paper are not discharged without being separated. Moreover, if the capacity of the fan is made more efficient, it will help to save energy. In addition, having one fan in time not only leads to significant cost savings in terms of space and materials, but also helps to save energy.

Example 2 In the diazo copying machine according to the second aspect, the base paper and the photosensitive paper are separated after the two sheets of the base paper and the photosensitive paper are brought into close contact with each other and irradiated with light.
At that time, the air suction force is used. Therefore, fans are provided on both sides of the machine, and the base paper and the photosensitive paper are separated by using the negative pressure generated by the suction of the fan.

Further, at this time, in consideration of the size of various papers to some extent, a large number of holes are formed so that the holes for suction match the papers, and separation is performed. After the separation, the paper is discharged to the front, the base paper is discharged to the front side, and the photosensitive paper is transported to the developing unit while holding the suction.

As described above, the hole of the suction unit is substantially in the shape of a tadpole. The head corresponding to the separation unit is large, and the tail corresponding to the transport unit is thin and long. This means that the suction force of the fan is negative pressure at that location ×
Utilizing the area, the separation unit that separates two closely adhered papers increases the suction force by increasing the area, and prevents the paper from being kinked in the transport unit and holds the paper uniformly. It is thin and long for this purpose. In the horizontal direction perpendicular to the paper transport direction, the holes have the same size and are relatively aligned with the paper (see FIG. 3 described in Example 1).

[0030] Incidentally, if the width of Majakushi shaped tail was your very fine corresponds to the head 4H as shown in FIG. 6
Large holes 4H distribute the 'side by side, a plurality of small holes 4T in which the total area of the holes to be equal to the area of the tail' at which corresponds to the tail.

On the other hand, in the case where a separation claw for forcibly pulling away from the suction cylinder is provided in order to proceed from the conveyance to the next development operation, there is a case where the separation claw is enlarged by that amount, Have the same area related to the suction force.

When large paper is used, no problem occurs because the paper uniformly closes the holes and is separated and transported by the negative pressure of the suction force. Since the paper does not reach that end and does not block the holes at both ends close to, the air is freely sucked in there, and the negative pressure at the central portion is reduced, leading to a reduction in the separation capacity. Therefore, the paper is not separated, and sometimes discharged in a non-separable state.

In this example, no matter what size the standard paper is used, such inseparability does not occur, so that the paper is provided slightly inside the both ends of the paper so as to match the standard paper. As shown in FIG. 5, the suction holes are separated so that they are separated from each other at an upstream position so as to be separated earlier in the lateral direction and at a downstream position at the center.

The reason for this is as follows. 2
As shown in FIGS. 1 and 4, the suction cylinders 1 and 2 for separating sheets of paper are close to each other on the upstream side but open toward the downstream side. For this reason, even when small-sized paper is used, the inflow of air is hindered due to the small width at both ends in the horizontal direction. Thus, the pressure drop is reduced and the suction force is not rapidly lost. In the case of a large paper, the paper is gradually separated from the outside, which is preferable in that it facilitates the flow of air between the closely adhered papers.

This example will be described more specifically. In general,
In a flow branch, the resistance is expressed as a sum of the square root of each resistance. Now, assuming that the resistance is the same for each hole, there will be a large suction from holes near the fan and a reduction in suction far from the holes.

The suction force used for paper separation is suction pressure × area. However, in the case of a diazo copying machine, since there are fans on both sides, the suction force is greater at both ends near the fan than at the center. ing. For this reason, when small paper is inserted, suction is performed in the area near the fan, which causes a large pressure loss, weakens the force to separate the small paper in the center, and discharges the original paper and photosensitive paper in close contact Done,
This causes so-called non-separation.

As a countermeasure, equalizing the suction force is one means, but simply increasing the inflow resistance that generates negative pressure at both ends may prevent the inflow. Therefore, the positions of the suction holes arranged at the same height in the paper transport direction (FIG. 3)
(See FIG. 5) at both ends in the horizontal direction.

The amount of movement is about 1-1.5 cm, which is about half of the substantially tadpole-shaped head. That is,
Even if papers of various sizes enter, large ones are sequentially separated from the end toward the center, and small papers come to the center and separate from both ends.

Even better, in the case of large paper, even if the paper closes the hole, the inflow is carried out at the center, so that there is a flow inside the suction cylinder, and the static pressure at that part becomes low. This is convenient for adsorbing large paper. In this case, a time difference may occur, and kinking may occur. However, when the height is about 1 cm, the time difference at the paper conveyance speed is usually 0.1 to 0.5 seconds. You don't have to worry about kinking.

As described above, according to the present embodiment, even when small paper is used for a large machine, the so-called non-separation of paper, which is the discharge of base paper and photosensitive paper without separation, is eliminated, and work efficiency is improved. I do. Further, mental inefficiencies such as inconvenient work procedures due to occasional inseparability can be eliminated.

[0041]

According to the present invention, the paper can be sufficiently separated without causing kinking of the paper in the transport section after the separation, and can be reliably performed regardless of the size of the paper.

[Brief description of the drawings]

FIG. 1 is a perspective view of a suction tube illustrating an embodiment of the present invention.

FIG. 2 is an explanatory view of a suction hole according to the present invention.

FIG. 3 is a diagram illustrating a suction hole according to the present invention in relation to a suction cylinder.

FIG. 4 is a diagram illustrating a state in which a base paper and a photosensitive paper are separated in a suction cylinder.

FIG. 5 is a diagram illustrating a state in which a base paper and a photosensitive paper are separated in a suction cylinder.

FIG. 6 is a diagram illustrating another example of a suction hole.

[Explanation of symbols]

 3Y Paper transport direction 3X Horizontal direction 4 Suction hole 4H Head 4T Tail

Claims (2)

(57) [Claims] 1. Two suction cylinders having a plurality of suction holes arranged side by side in a horizontal direction perpendicular to the paper conveying direction are arranged so that the suction holes of the suction tubes face each other. Separate the two sheets of paper by suctioning air from one side and sending it while suctioning one of the two sheets of paper sent from the upstream to one suction cylinder and the other into the other suction cylinder. In the paper separation device, the suction hole is at least approximately a tadpole-shaped or large hole.
A combination of at least one small hole, and
In case of a comb shape, the head should be on the upstream side in the paper
Part is directed to the downstream side, and the combination of the large hole and the small hole
In the case of alignment, the large hole is located on the upstream side in the paper
Small holes are positioned slightly inward from the standard paper placed downstream a plurality juxtaposed, the increased distance from the center on the horizontal direction, the paper separator, characterized in that the smaller the area of the suction holes apparatus. 2. The paper separating apparatus according to claim 1, wherein the position of the suction hole is set to be upstream as the distance from the center in the horizontal direction increases.