Metallurgical apparatus – With control means responsive to sensed condition – With temperature sensor
Reexamination Certificate
2000-04-18
2002-01-22
Kastler, Scott (Department: 1742)
Metallurgical apparatus
With control means responsive to sensed condition
With temperature sensor
C266S103000, C432S043000, C432S059000
Reexamination Certificate
active
06340444
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a heat treatment apparatus for performing heat treatment of a sheet which must be treated, and more particularly to a heat treatment apparatus for use to, with heat, develop a material having an image formed thereon in a dry system which does not require a wet process and which uses a dry material.
The wet system has been employed in, for example, an image recording apparatus for printing a plate, a digital radiography system arranged to use a heat accumulative fluorescent sheet, and an image recording apparatus for recording an image for medical use, such as CT or MR. The wet system is arranged to photograph or record an image on a silver-salt photosensitive material, followed by performing a wet process so as to obtain an image.
On the other hand, a different recording apparatus has attracted attention. The recording apparatus employs a dry system which does not require the wet process. In the recording apparatus of the dry type, a photosensitive and/or a thermal recording material (a thermal and photosensitive recording material) or a film (hereinafter called a “recording material) constituted by a thermal development photosensitive material is employed. The recording apparatus using the dry system incorporates an exposing portion for irradiating (scanning) the recording material with a laser beam to form a latent image. Then, a thermal development portion of the system brings the recording material into contact with a heat means to perform thermal development. Then, the recording material having an image formed thereon is discharged to the outside of the apparatus.
The dry system is able to form an image in a shorter time as compared with the wet process. Moreover, the necessity for disposing waste solution required of the wet process can be overcome. Therefore, increase in the demand for the dry system has been expected.
A portion of the foregoing conventional dry system has a structure that the heat development portion incorporates, for example, a heating means and a pressing/moving means to hold and move the recording material by the heating means and the pressing/moving means so as to perform heat development. That is, the recording material is heated to a predetermined temperature so as to be developed with heat when the recording material is held and moved between the heating means and the pressing/moving means. If the recording material cannot be heated sufficiently at this time, uneven development occurs. Since the recording material for dot printing has high sensitivity because a dot image for printing must have excellent image quality, the image quality considerably deteriorates if heating cannot be performed to the predetermined temperature. It leads to a fact that a temperature sensor has been provided for the heating means so as to accurately control the temperature in accordance with the temperature detected directly.
The heating apparatus has an inspection cover which is sometimes opened and closed owing to occurrence of a jam or the like. Thus, the heat development portion is cooled to the outside air temperature. In the foregoing case, the temperature is lower than the predetermined temperature for some time even after the inspection cover has been closed. It leads to a fact that the heating means incorporating the provided temperature detection sensor directly detects the decrease in the temperature. Therefore, the temperature can relatively quickly be returned to the predetermined temperature. On the other hand, the other members in the heat development portion except for the heating means are returned to the predetermined temperature at individual raising rate. Therefore, when the temperature is again raised after interruption of heating, the temperatures of members which concern the heat development must accurately be detected. Moreover, control must be performed such that the temperatures of the members are returned to the predetermined temperature.
The pressing/moving means which is brought into contact with the recording material in a direct manner exerts a great influence of the temperature thereof on the development temperature. To maintain frictional force with the recording material, the pressing/moving means is coated with a silicon rubber or the like. Therefore, temperature sensor cannot directly be brought into contact with the pressing/moving means. Thus, the temperature of the pressing/moving means cannot be detected. Hence it follows that there is a requirement for detecting the temperature of the pressing/moving means to realize more accurate control of the temperature in the heat development portion.
In the dry system, the thermal development portion is usually provided with a heat drum which serves as a heating means. An endless belt is wound around the heating drum for a predetermined angle. Thus, the heating drum and the endless belt are used to hold and move the recording material to perform the heat development. If the endless belt cannot maintain uniform tension, required contact between the recording material and the heating drum cannot be established. Thus, uneven development occurs.
Since a dot image which must be printed is required to have excellent image quality, the sensitivity of the recording material has greatly been improved. Therefore, unsatisfactory contact with the heating drum encounters excessive deterioration of the image quality.
The heating means encounters a problem in that the temperature is decreased at an end portion to which heat cannot sufficiently be supplied. Moreover, the heating means suffers from undesirable bending and occurrence of a wrinkle caused from buckling of an end portion of the recording material which takes place when the recording material is held between the heating drum and the endless belt. The wrinkle becomes conspicuous in a case where a recording material (for example, a recording material for making a plate for a newspaper) of a type having a large size and great thickness is used.
SUMMARY OF THE INVENTION
An object of the invention is to enable more accurately control of the temperature of a heat development portion to be performed by employing a structure which is capable of detecting the temperature of the pressing/moving means.
Another object of the present invention is to provide a heat treatment apparatus which is capable of making the contact between the heating member and a recording material to furthermore be uniform, preventing occurrence of a wrinkle, realizing furthermore uniform heating and therefore capable of forming an image exhibiting high quality free from uneven development.
A heat treatment apparatus according to the present invention comprises:
a heating member which subjects a sheet to a heating process at a predetermined temperature;
moving means which moves the sheet;
a temperature-measured member, the temperature of which is measured and changed with a relationship with change in the temperature of the moving means and which is provided at a position adjacent to the moving means;
a temperature sensor disposed in contact with the temperature-measured member so as to measure the temperature of said temperature-measured member; and
temperature control means which controls the temperature of the moving means in accordance with a result of detection of the temperature performed by the temperature sensor.
The heat treatment apparatus incorporates the temperature sensor with which the temperature of the temperature-measured member is measured. The detected temperature is corrected in accordance with the relationship between change in temperature of the moving means and a change of a temperature of the temperature-measured member. Therefore, the temperature of the moving means which cannot be detected by the conventional technique because direct contact has been inhibited can be detected. It leads to a fact that accurate control of heating corresponding to the detected temperature of the moving means can be performed. Therefore, a predetermined temperature of the moving means can be maintained. If the tem
Fuji Photo Film Co. , Ltd.
Kastler Scott
Sughrue & Mion, PLLC
LandOfFree
Heat treatment apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Heat treatment apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Heat treatment apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2856078