JP2984241B2 - Roller heat treatment equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roller heat treatment apparatus for performing heat treatment such as heat development and heat fixing on a curable sheet such as paper or film.

[0002]

2. Description of the Related Art A roller heating apparatus for subjecting a sheet to be subjected to a heat treatment such as thermal development or heat fixing includes a heat roller for heating the sheet to be treated and a backup for pressing the sheet to be treated against the heat roller. It has a pair of rollers with a roller. Then, the sheet to be processed is supplied between the two rotating rollers, and heat-treated while moving in a state of being pressed against the heat roller. This backup roller is
The surface is made of elastic material such as silicon rubber so that the sheet can be pressed securely.
Heat rollers, on the other hand, are also called soft rollers.
In order to improve heat conduction, the surface of an aluminum pipe is often coated with Teflon etc., also called a hard roller, inside which a tubular heater lamp such as a halogen bulb is arranged along the axial direction .

In such a roller heat treatment apparatus, it is necessary to heat the sheet to be processed at a uniform temperature for a predetermined time. That is, it is necessary that the temperature distribution in the axial direction of the heat roller is uniform and the sheet to be processed is pressed against the heat roller for a predetermined time.

In the case where the required heating time is relatively short, as in the case of thermal fixing such as a PPC or a laser printer, a predetermined heating time can be secured only by heating between a pair of rollers. When performing a heat treatment requiring a relatively long heating time as in the case of developing a type diazo thermosensitive paper, there is a problem that the rotation speed of the roller needs to be reduced, and the development time becomes longer. In order to solve this problem, a plurality of backup rollers are arranged around the heat roller, and a guide member slightly separated from the peripheral surface of the heat roller is provided between the backup rollers.

[0005]

The roller heat treatment apparatus provided with such a guide member has almost no problem when the sheet to be processed is ordinary paper, and can perform accurate development. In the case of a film for forming the “second base paper” or paper with poor air permeability, “speckles” and “irregularities” are formed in unspecified areas of the sheet to be processed, and furthermore, streaky incompletely developed areas. The problem that occurs was clarified.

Various investigations of the cause revealed that the specialty of the material of the sheet to be processed is delicately related to the transport speed of the backup roller. In other words, when a plurality of backup rollers are provided, in order to prevent the sheet to be processed from being loosened between the backup rollers, for example, by changing the diameter of the sprocket or the number of gears, the backup roller in the subsequent stage is slightly faster than the other backup rollers. By rotating the sheet, the sheet to be processed is put in a pulled state to prevent wrinkles and improve the adhesion to the heat roller.

However, when the sheet to be processed is a film or paper having poor air permeability, the sheet absorbs a large amount of water in a high-temperature and high-humidity state, and enters the first backup roller.
When heated in close contact with the heat roller, moisture evaporates rapidly, and the sheet to be processed such as a film expands and contracts. Therefore, when the sheet to be processed is pulled by the backup roller at a later stage that rotates slightly faster and adheres to the heat roller and is developed, the sheet to be processed such as a film has low air permeability, so that the trapped water vapor and the sheet to be processed are low. It was found that the development unevenness and the “irregularity” described above occurred due to the interaction with the expansion and contraction of the film.

Accordingly, the present invention is directed to a roller heating apparatus capable of completely developing without causing development unevenness or "irregularities" even when a film or paper having low air permeability is used as a sheet to be processed. It is an object to provide a processing device.

[0009]

In order to achieve the above object, according to the first aspect of the present invention, a paper or the like is provided between a heat roller having a heater lamp therein and a plurality of backup rollers which are in pressure contact with the heat roller. In a roller heat treatment device where a bendable sheet such as a film is supplied, heated, and discharged, "slack" is always formed on the sheet immediately after the backup roller through which the sheet first passes. Means for rotating each backup roller at substantially the same peripheral speed.

According to a second aspect of the present invention, in the first aspect of the present invention, a guide member formed of a bendable plastic plate is provided between the backup rollers such that a central portion thereof contacts the peripheral surface of the heat roller. .

[0011]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 shows a heat development type diazo copying machine. An exposure unit A and a heat development unit B are housed in a casing 1 having an inverted W-shaped upper surface, and the roller heat treatment apparatus of the present invention is applied to the heat development unit B.

The casing 1 has a supply port 11a for superposing the original sheet on which the diazo thermosensitive material is applied and the original drawing and supplying the same to the exposure unit A, and a discharge port 1 for discharging after exposure.
2a, and further provided with a supply port 11b for supplying the exposed sheet to be processed to the thermal developing section B, and a discharge port 12b for discharging after the thermal development. In the exposure part A, a transparent glass cylinder 101 is rotatably arranged, and a tube-type fluorescent lamp 102 having a rating of 100 W is arranged along the axis inside the cylinder 101. An endless backup belt 105 is wound around the four idle rollers 103, one drive roller 104, and the cylinder 101, and the backup belt 105 holds the cylinder 101. Therefore,
When the drive roller 104 is driven and rotated, the cylinder 1 is rotated.
01 rotates in the direction of the arrow.

Next, a heat roller 2 is rotatably arranged in the heat developing section B. The heat roller 2 is formed by coating a surface of an aluminum pipe with Teflon, and has a heater lamp 21 formed of a tubular halogen bulb having a rated power consumption of 1 kW along an axis thereof. Around the heat roller 2, four backup rollers 3 are rotatably arranged. The backup roller 3 is made of silicon sponge and has a high elasticity, and each of them is pressed against the heat roller 2.
For this reason, the contact portion is slightly deformed following the curvature of the heat roller 2, and the contact area between them is widened. The endless drive chain 5 is wound around the sprocket 4 attached to one end of each shaft 31 of the backup roller 3, the idler 8 freely rotatable, the drive roller 104, and the output shaft 61 of the motor 6. When the motor 6 rotates, the backup roller 3 is driven to rotate in the direction of the arrow.

Here, each backup roller 3 and each sprocket 4 are designed to have the same size, and each backup roller 3 rotates at the same peripheral speed. Therefore, as the backup roller 3 rotates,
The heat roller 2 rotates following the rotation. In addition, a temperature sensor 10 is in contact with the surface of the heat roller 2 so that the surface temperature of the heat roller 2 can be controlled within a predetermined range.

A guide member 9 is arranged between the backup rollers 3 along the peripheral surface of the heat roller 2. The guide member 9 is made of a bendable polyester resin plate, and has a central portion in contact with the heat roller 2. The positional relationship between the guide member 9 and the sheet S to be processed will be described with reference to FIG. 2. When the leading end of the sheet S to be processed passes through the first backup roller 3a and hits the guide member 9 and enters the press contact area L, Due to the sliding resistance, the advance of the leading end of the sheet to be processed S is slowed, and a “slack” U is formed in the sheet to be processed S. That is, the sheet S to be processed is partially released from the heat roller 2 to form the space Q. Therefore, the water vapor generated when passing through the backup roller 3a is released from the space Q.

Next, the leading end of the sheet S to be processed sequentially advances to the next backup roller 3b, and further to the subsequent backup roller. The processing sheet S is not pulled by the backup roller 3 at the subsequent stage, and the “slack” U does not disappear. That is, since the empty space Q is always formed,
Even if the portion of the sheet S to be processed from the central portion to the latter half portion passes through the first backup roller 3a and generates steam, the steam is released from the space Q without being closed.

When the power switch (not shown) is
N, the heat roller 2 is heated to a predetermined temperature, and when the fluorescent lamp 102 is stabilized, a copy switch (not shown)
Is turned on to rotate the motor 6. Then, when the original drawing is overlapped with the film to be processed, which is a film coated with a diazo thermosensitive material or a sheet having low air permeability, and inserted from the supply port 11a, the sheet is moved by being pressed against the cylinder 101 by the backup belt 105. It is exposed in the process and is discharged from the discharge port 12a.

Next, when the sheet to be processed is separated from the original drawing and supplied from the supply port 11b, the backup rollers 3
Is pressed against the heat roller 2 and thermally developed while moving. Here, the leading end of the sheet to be processed passes through the first backup roller 3 and “slack” is formed. However, as described above, “slack” is always formed without disappearing in the process of the sheet to be processed. ing. Therefore, even if the sheet to be processed is a film or a paper having low air permeability, water vapor can be reliably removed from the entire area of the sheet to be processed, and heat development is completely performed, resulting in uneven development and “unevenness”. Does not occur. Then, the sheet subjected to the heat development is guided to the scraper 7 and discharged from the discharge port 12b.

[0019]

As described above, the roller heat treatment apparatus of the present invention includes a means for rotating each backup roller at substantially the same peripheral speed, and immediately after the backup roller through which the sheet to be processed first passes, Since the sheet to be processed is advanced so that “slack” is always formed on the sheet to be processed, the “slack” is generated over the entire area of the sheet to be processed.
Water vapor can be reliably removed from the water. Therefore, even if the sheet to be processed is a film or a paper having low air permeability, development unevenness and “irregularities” do not occur.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a main part.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Casing 2 Heat roller 21 Heater lamp 3 Backup roller 4 Sprocket 5 Drive chain 6 Motor 9 Guide member A Exposure part B Thermal development part U Slack

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-150842 (JP, A) JP-A 1-172046 (JP, U) JP-A 2-58235 (JP, U) JP-A 4-58 57850 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03D 13/00 G03G 15/20 H05B 3/00

Claims (2)

(57) [Claims] A bendable sheet such as paper or film is supplied between a heat roller having a heater lamp therein and a plurality of backup rollers pressed against the heat roller, and is heated and discharged. Means for rotating each backup roller at substantially the same peripheral speed so that “slack” is always formed on the sheet to be processed immediately after the backup roller through which the sheet to be processed first passes. A roller heat treatment device, comprising: 2. The apparatus according to claim 1, wherein a central portion of a guide member made of a bendable plastic plate is provided between the backup rollers so as to contact a peripheral surface of the heat roller. Roller heat treatment equipment.