Printing – Processes – With heating or cooling
Reexamination Certificate
2002-02-19
2003-09-09
Eickholt, Eugene H. (Department: 2854)
Printing
Processes
With heating or cooling
C399S044000, C399S069000
Reexamination Certificate
active
06615733
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a heat developing apparatus in which a heat processing section to heat develop a heated developing sheet on which a latent image by an exposure is formed, is opened toward the outside of the apparatus by the opening and closing of an opening and closing cover, and particularly to the control technique of the rising temperature of the heat processing section.
2. Description of the Related Art
In a plate making image forming apparatus for making a plate-making for printing, or an image forming apparatus to record a medical image such as a Computed Tomography or Magnetic Resonance, an image forming apparatus by using a dry system which forms the image by the heat developing, without conducting the wet processing, is remarked. In such the image forming apparatus, a photosensitive and/or heat sensitive recording material (photosensitive heat sensitive recording material) or film of heat developing photosensitive material (hereinafter, called heated developing sheet) is used, and a latent image formed by irradiating (scanning) the laser beams, is developed by the heat, and the image is formed. In the image forming apparatus by such the dry system (hereinafter, called heat developing apparatus), not only the image formation can be attained in a shorter time than the wet processing, but a problem of waste solution processing can also be eliminated, and it is fully presumed that the demand will be increased in the future.
Conventionally, this heat developing apparatus is structured, as a main structure, by a conveyer to supply and convey the heated developing sheet after the latent image formation, preliminary heating section to preliminarily heat, main heating section corresponding to a developing section, gradually cooling section to gradually cool the heated developing sheet which is heat developed by the main heating section, and exhaust section to exhaust the gas generated in the apparatus.
The preliminary heating section is structured in such a manner that a plurality of roller units each of which is structured by a heating roller and a conveying roller, are arranged at an equal interval along the conveying direction of the heated developing sheet. The closer a heating roller is to the main heating system, the higher the heating temperature of the heating roller is, and it is set so that, when the heated developing sheet passes the heating roller closest to the main heating section, the temperature of the heated developing sheet is increased to the developing temperature.
The main heating section is structured in such a manner that a plurality of heating units in which a heat plate and a plurality of conveying rollers and sub-heater are arranged, are arranged along the conveying direction of the heated developing sheet. The heated developing sheet is nipped by the heat plate and the conveying roller, and heated at the developing temperature while being conveyed, and advances to the gradually cooling section side.
The gradually cooling section is structured in such a manner that a slanting section is arranged between a sending roller structured by a pair of conveying rollers, and a delivery roller structured by a pair of conveying rollers. The falling speed of the heated developing sheet after development is adjusted in the gradually cooling section by the sending roller and the delivery roller, and the sheet is gradually cooled to about the room temperature at a predetermined cooling speed.
According to the heat developing apparatus structured as described above, because the apparatus is provided with the preliminary heating section and the gradually cooling section, the quick temperature change (quick temperature rise and down) is not caused on the heated developing sheet, and the developing is smoothly and surely conducted. That is, in the preliminary heating section, at the temperature difference by which the developing unevenness due to the deformation of the substrate of the heated developing sheet is not generated, the sheet is preliminarily heated to the developing temperature in stages. Accordingly, in the main heating section, because the temperature of the sheet is not instantaneously raised from a low temperature to the developing temperature, the generation of the developing unevenness due to the large deformation of the substrate is suppressed. Then, because the gradually cooling is conducted in the gradually cooling section, the generation of the wrinkle or lowering of the image quality due to the quick temperature down is prevented.
In the heat developing apparatus, at the time of start from the unused condition, or the start after return from the jam, the quick responsibility of the startup temperature and the temperature stability is required. However, in an ordinary PID (Proportional, Integral, Derivative) control or ON/OFF control, the temperature of the heater and the portion near the heater is stabilized soon, but the response of the temperature of the portion apart from the heater is slow. Therefore, in order to raise the temperature to the predetermined temperature soon, it is conducted that the temperature of the heater is raised to the higher temperature than the stable temperature once. In the temperature control method in this case, the raised temperature and the raising time are controlled amounts.
However, conventionally, at the time of startup, the temperature drop amount at the time of startup is detected by one temperature sensor, and corresponding to that, the control amount is set. Because of that, the temperature control method can cope with the temperature around the detecting portion, however, to the temperature of the other portions, it is not always the optimum control amount. For example, even when the apparatus is started in the same manner, the two kinds of temperature drops cannot be distinguished from each other. That is, a case where the start is a start from the condition that the opening and closing cover is closed (power source is turned off), or a case where the operating apparatus is stopped once when the cover is opened by the jam, and after the restore from the jam, the apparatus is started again, are not distinguishable. Accordingly, in the latter case, when the controlled amounts are set to the same as in the former case, the portion at which the temperature is too high is generated.
SUMMARY OF THE INVENTION
In view of the foregoing, the present invention is attained, and the object of the present invention is to provide a temperature control method of a heat developing apparatus by which, for various operating conditions of the apparatus, the optimum temperature control amounts can be determined, and a heat developing apparatus, and thereby, to secure the quick responsibility of the startup temperature.
A temperature control method of the heat developing apparatus according to the first aspect of the present invention to attain the above object, is a temperature control method of a heat developing apparatus in which a heat processing section to conduct the heat developing on a heated developing sheet on which a latent image by the exposure is formed, is opened toward the apparatus outside by an opening and closing motion of an opening and closing cover, wherein a temperature detection is conducted by a first sensor which is arranged in the vicinity of a conveying path of the heated developing sheet of the heat processing section and to be exposed to the outside of the apparatus when the opening and closing cover is opened; simultaneously, a temperature detection is conducted by the second sensor which is arranged in the heat processing section and to be kept unexposed to the outside of the apparatus when the opening and closing cover is opened; and an optimum combination of a control variable and a control amount is selected from predetermined combination of control variables and control amounts corresponding to the combination of each temperature detected by the first and the second sensor, and the temperature control of the heat processi
Eickholt Eugene H.
Fuji Photo Film Co. , Ltd.
Sughrue & Mion, PLLC
LandOfFree
Temperature control method of heat developing apparatus and... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Temperature control method of heat developing apparatus and..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Temperature control method of heat developing apparatus and... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3062580