Drying device

Information

  • Patent Grant
  • 6813846
  • Patent Number
    6,813,846
  • Date Filed
    Wednesday, March 27, 2002
    22 years ago
  • Date Issued
    Tuesday, November 9, 2004
    19 years ago
Abstract
A photosensitive material is dried by radiating heat from a guide plate, having high emissivity, which is disposed along a conveying path and is heated by a ceramic heater. Further, the photosensitive material is dried by a warm air, which is heated by a heater, blown onto the photosensitive material from nozzles. In the drying, because the warm air is also heated by the heated guide plate, the warm air can be risen to a predetermined temperature efficiently. Accordingly, because transferring the radiating heat and the blowing the warm air are performed at a same position (a same member), the drying can be performed efficiently without enlarging the device.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a drying device for drying a wet image recording medium.




2. Description of the Related Art




In recent years, printing devices utilizing a digital exposure, namely, digital photographic printers, have been put into practice. The digital photographic printer is a device in which an image recorded on a film is read in a photoelectric manner, the read image is converted to digital signal, the digital signal is subject to various image processings to obtain image data for recording, an image (a latent image) is formed on a photosensitive material by scanning and exposing the photosensitive material with a recording light modulated in accordance with the image data, the photosensitive material is subject to developing processing, and a print (a photograph) is output.




A processor included in the digital photographic printer described above is provided with a developing section and a drying section. The developing section performs the developing processing in which the photosensitive material on which the latent image is formed is immersed in a developing tank. The drying section dries the developed photosensitive material.




A structure of the drying section for drying the photosensitive material thereat is well known in which a hot (warm) air is blown to the conveyed photosensitive material. Also, in recent years, a structure of the drying section in which radiation heat is utilized to improve a drying speed of the photosensitive material is proposed.




It is a disadvantage of the structure of the drying section in which the warm air is blown to the photosensitive material described above that drying efficiency is low because large amount of heat losses, from a side surface of a duct providing the warm air, to the outside.




When the drying section is structured such that the radiation heat is also utilized, it is necessary to provide both a section for drying in which the warm air is blown and a section for drying in which the radiating heat is utilized, at the drying section. Accordingly, It is a disadvantage that the drying section becomes large.




Moreover, when the drying section is structured such that the radiation heat is utilized, it is proposed that material which has high emissivity and high thermal conductivity is applied to a conveying system of the drying section. However, because this conveying system is heated by the warm air, the radiation heat is not used actively.




Moreover, there is another problem that unevenness of drying state of the photosensitive material may occur due to blowing positions of the warm air not existing appropriately.




SUMMARY OF THE INVENTION




The present invention was developed in order to overcome the above-described drawbacks, and an object of the present invention is to provide a drying device which can perform drying efficiently without enlarging the drying device.




In order to achieve the above object, an image drying device of a first aspect of the present invention is a drying device for drying a wet image recording medium conveyed along a conveying path, comprising: a plate member disposed along the conveying path, the plate member including blowing holes through which a wind for drying is blown onto the image recording medium and facing the conveyed image recording medium; and a heating device for directly heating the plate member, the heating device being disposed on or inside the plate member.




In an image drying device of a second aspect of the present invention according to the first aspect, at least a surface, which faces the image recording medium, of the plate member comprises a material having high emissivity.




A drying device of a third aspect of the present invention is a drying device for drying a wet image recording medium conveyed on a conveying path, comprising: a plate member disposed along the conveying path, the plate member including blowing holes through which a wind for drying is blown onto the image recording medium and facing the conveyed image recording medium; a first heating device for directly heating the plate member, the heating device being disposed on or inside the plate member; and a second heating device disposed at a wind for drying supplying path for supplying the wind for drying to the blowing holes of the plate member, wherein the wind for drying is heated by both the first heating device and the second heating device.




In an image drying device of a fourth aspect of the present invention according to anyone of the first aspect through the third aspect, the device further comprises a conveying member for conveying the image recording medium, the conveying member facing the plate member and being disposed such that the conveyed image recording medium is interposed between the plate member and the conveying member, wherein the image recording medium is conveyed in a state in which an image recording surface of the image recording medium faces the plate member, and the image recording medium is conveyed in a state in which the image recording medium is pressed in a direction of the conveying member by one of wind pressure of the wind for drying blown from the blowing holes and negative pressure of a blowdown side of the wind for drying, such that the image recording medium does not surface-contact the plate member.




In an image drying device of a fifth aspect of the present invention according to anyone of the first aspect through the fourth aspect, at least one rib is provided at a surface, which faces the image recording medium, of the plate member, the rib extending both downstream in a conveying direction of the image recording medium and laterally in a width direction, from a substantial center of the plate member toward a substantial width-direction edge of the plate member, the width direction being orthogonal to the conveying direction.




In an image drying device of a sixth aspect of the present invention according to anyone of the first aspect through the fifth aspect, portions of blowing holes which are located in different positions in a conveying direction of the image recording medium and which are adjacent in a width direction of the plate member when viewing along the conveying direction, are overlapped.




In an image drying device of a seventh aspect of the present invention according to anyone of the first aspect through the sixth aspect, an opening rate of the blowing holes with respect to the plate member is equal to or more than 2% and equal to or less than 10%.




In an image drying device of an eighth aspect of the present invention according to anyone of the first aspect through the seventh aspect, a temperature sensor is disposed at the plate member.




The first aspect of the present invention will be described in detail.




Because the plate member is disposed at the position in which the plate member faces the image recording medium along the conveying path, and the heating device heats directly the plate member, the conveyed image recording medium is dried by a radiating heat of the heated plate member. At the same time, the wind for drying (a warm air) which is from the blowing holes formed on the plate member and which is heated by the heating device, is blown onto the image recording medium. Accordingly, the image recording medium can be dried further efficiently.




In particular, because the heating device heats directly the plate member, amount of the radiating heat can be made large. Therefore, drying speed (drying efficiency) can be improved. Further, because the wind for drying is heated by the heated plate thereby be a warm air, it can be suppressed that the warm air is cooled due to heat loss or the like from a duct by the time when the warm air reaches to the blowing holes. Also, a portion to be heated (heat capacity) is made relatively small. Accordingly, a time necessary for heating can be reduced. Further, in the present invention, the radiating heat of the plate member in which the blowing holes are provided is utilized, the radiating heat and the wind for drying can be utilized at a same portion, therefore, the enlargement of the device can be suppressed.




The second aspect of the present invention will be described in detail.




Because at least the surface, which faces the image recording medium, of the plate member is formed by the material having high emissivity (a total emissivity is equal to or more than 0.9), the radiating heat is transferred from the plate member heated by the heating device to the image recording medium efficiently. Accordingly, drying efficiency of the image recording medium can be improved.




The third aspect of the present invention will be described in detail.




Because the first heating device is provided at the plate member and the second heating device is provided at the wind for drying supplying path for providing the wind for drying to the blowing holes of the plate member, and the wind for drying is heated by both the first heating device and the second heating device, a temperature of the wind for drying can be made high efficiently. Accordingly, drying efficiency of the image recording medium can be improved.




The fourth aspect of the present invention will be described in detail.




The image recording medium which has reached to the drying device is conveyed in the state in which the image recording surface of the image recording medium faces the plate member. At this time, the image recording medium is conveyed in the state in which the image recording medium is pressed toward (and abutted on) the conveying member which is disposed to face the plate member, namely, in a state in which the plate member is apart from the image recording medium, by the wind pressure of the wind for drying blown from the blowing holes of the plate member or the negative pressure of the blowdown side of the wind for drying. Accordingly, it is prevented that the image recording medium is conveyed in a state in which the image recording medium slides with respect to the plate member by surface-contacting each other. Accordingly, it can be surely prevented that the image recording surface of the image recording medium is damaged.




The image recording medium may be made curled in the width direction which is orthogonal to the conveying direction in accompany with being dried, and therefore, the end portions of the image recording medium may abut the plate member. However, even when the end portions of the image recording medium in the width direction abut (line-contact) the plate member, the image recording surface of the image recording medium cannot be damaged.




The fifth aspect of the present invention will be described in detail.




The image recording medium being conveyed in the drying device may be made curled in the width direction which is orthogonal to the conveying direction in accompany as being dried. As a result, tip ends of the both end portions in the width direction of the image recording medium (hereinafter, tip corners) may slide on the plate member. At this time, it may happen that the tip corners enter the blowing holes formed in the plate member and the tip corners are damaged, and/or the image recording medium is jammed.




However, in this aspect, because at least one rib (protrusion) is provided at the surface, which faces the image recording medium, of the plate member, such that the rib extends toward the downstream side of the conveying direction of the image recording medium, from the substantial central portion of the plate member in the width direction which is orthogonal to the conveying direction, to the substantial end portion of the plate member in the width direction, the tip corners abutting the plate member are guided by the protrusions to move toward respective end portions of the plate member. Namely, the curled image recording medium is made to be plane by the protrusions. Therefore, an angle of the tip corner with respect to the plate member is made small. Accordingly, a possibility that the tip corners enter in the blowing holes can be reduced. Accordingly, the damaging of the image recording medium and/or the jamming of the image recording medium can be suppressed.




The sixth aspect of the present invention will be described in detail.




The blowing holes are disposed such that the portions of blowing holes located in different positions in the conveying direction of the image recording medium and neighboring each other in the width direction of the plate member when viewing along the conveying direction, are overlapped.




Namely, blowing holes are aligned in columns substantially orthogonal to the conveying direction, with blowing holes in respectively adjacent columns being offset in the conveying direction, such that blowing holes in respectively adjacent columns would partially overlap if a column were to be superimposed on an adjacent column in the conveying direction.




Accordingly, as the image recording medium is conveyed on the conveying path, the wind for drying can be blown onto the image recording medium in entire area in the width direction without non-uniformity. Therefore, unevenness of amount of the wind for drying blown onto the image recording medium in the width direction can be suppressed. Therefore, unevenness of drying state of the image recording medium can be suppressed.




The seventh aspect of the present invention will be described in detail.




The drying efficiency of the image recording medium by the wind for drying depends on a wind velocity of the wind for drying. In this aspect, the opening rate of the blowing holes with respect to guide plate is equal to or more than 2% and equal to or less than 10%. By this structure, the blowing speed (wind velocity) of the wind for drying is equal to or more than a predetermined value, the drying efficiency of the image recording medium can be improved.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a schematic structural view of a processor relating to a first embodiment of the present invention.





FIG. 2

is a schematic side view of a drying section relating to the first embodiment of the present invention.





FIG. 2A

shows a guide plate and a heater in an alternative embodiment of the present invention.





FIG. 3

is a schematic front view of the drying section relating to the first embodiment of the present invention.





FIG. 4

is a plane view of a guide plate relating to the first embodiment of the present invention.





FIG. 5

is a structural plane view of arrangement of nozzles at the guide plate relating to the first embodiment of the present invention.





FIG. 6

is a front cross-sectional view of state of a photosensitive material at the drying section relating to the first embodiment of the present invention.





FIG. 7

is a perspective view of the state of the photosensitive material at the drying section relating to the first embodiment of the present invention





FIG. 8

is a schematic side view of a drying section relating to a second embodiment of the present invention.





FIG. 9

is a graph showing a relation between a drying rate and an opening rate of nozzle.











DESCRIPTION OF THE PREFERRED EMBODIMENTS




Hereinafter, embodiments of the present invention will be described.




(First Embodiment)




Hereinafter, a processor applied thereto a drying device relating a first embodiment of the present invention will be described in detail with reference to the drawings.




(Entire Structure of Processor)




A processor


10


is a device in which a photosensitive material, on which a latent image is formed by a printer (not shown in the drawings), is inserted, and the inserted photosensitive material is subject to developing processing and outputted as a print. Namely, as shown in

FIG. 1

, the processor


10


is provided with a developing section


14


, a drying section


16


and a discharge section


18


. The developing section


14


is provided with a developing tank


20


, a fixing tank


22


and a washing tank


24


along a conveying path. At the developing section


14


, by the photosensitive material being immersed in the developing tank


20


, the fixing section


22


and the washing section


24


in order, the latent image formed on the photosensitive material is developed and fixed. At the drying section


16


, the photosensitive material wetted at the developing section


14


is dried. The dried photosensitive material is discharged outside the processor at the discharge section


18


.




(Structure of Drying Section)




As shown in

FIG. 2

, the drying section


16


is basically structured such that it is provided with pairs of squeeze rollers


30


and


32


, a guide plate


34


and a conveying belt


36


. The pairs of squeeze rollers


30


and


32


remove extra water from the photosensitive material which is conveyed from the developing section


14


. The guide plate


34


guides the photosensitive material which has passed through the pair of squeeze rollers


32


toward the downstream side in a conveying direction. The conveying belt


36


is disposed at a position facing the guide plate


34


and conveys the photosensitive material.




As shown in

FIG. 2

, the guide plate


34


is provided with a sloped portion


34


A and a horizontal portion


34


B. The sloped portion


34


A guides the photosensitive material which has passed through the pair of squeeze rollers


32


to a portion between the horizontal portion


34


A and the conveying belt


36


. The horizontal portion


34


B is disposed so as to be substantially parallel with respect to the conveying belt


36


.




The guide plate


34


is formed by aluminum, and a surface


35


A of the guide plate


34


, facing the photosensitive material, is painted (coated) in black. Accordingly, a thermal conductivity of the guide plate


34


is high, and therefore, an emissivity (a radiation rate) of the guide plate


34


with respect to the photosensitive material is also high. (A total emissivity is equal to or more than 0.9.)




Ceramic heaters


38


A and


38


B are mounted on a lower side


35


B of the guide plate


34


. The photosensitive material is dried by a radiation heat of the guide plate


34


heated by the ceramic heaters


38


A and


38


B.

FIG. 2A

shows an alternative embodiment of the present invention in which ceramic heater


38


B is disposed inside guide plate


34


.




As shown by broken lines in

FIG. 4

, the ceramic heaters


38


A and


38


B extend in a width direction (a direction indicated by arrow “Y”) which is orthogonal to the conveying direction (a direction indicated by “X”). Accordingly, unevenness of the amount of the radiation heat transferred to the conveyed photosensitive material in the width direction can be suppressed.




A plurality of nozzles


40


are disposed on the guide plate


34


in such a manner that a plurality of columns, in which nozzles


40


are arranged in the width direction of the guide plate


34


by a constant interval, are arranged in the conveying direction by a predetermined interval.




The warn air is blown onto the photosensitive material, which is conveyed between the guide plate


34


and the conveying belt


36


, passing through the nozzles


40


. As shown in

FIG. 3

, air is heated by a heater


44


to a temperature substantially 60° C.-90° C., and the heated air (the warm air) is provided to a drying air supplying path


42


(hereinafter, a supplying path


42


), which is formed at the lower side of the guide plate


34


in the width direction, by a fan


46


, and then the warn air is provided to the photosensitive material through the nozzle


40


. As shown in

FIG. 3

, a temperature sensor


70


is mounted on the guide plate


34


. The heater


44


is feedback-controlled on the basis of the detected temperature detected by the temperature sensor


70


.




As shown in

FIG. 5

, each of the nozzles


40


has a circular hole portion having a diameter D. The nozzles


40


are arranged in the conveying direction (direction X) with intervals “J” and in the width direction (direction Y) with intervals “K”. Nozzles


40


in columns neighboring (adjacent) each other in the conveying direction (for example, a nozzle


40


A and a nozzle


40


B in

FIG. 5

) are arranged to be overlapped in the width direction by (¼)D. Accordingly, by the photosensitive material being conveyed on the guide plate


34


in the conveying direction, the warm air is blown, without unevenness in the width direction, onto the photosensitive material. Therefore, unevenness of drying in the width direction of the photosensitive material can be suppressed. In a case in which the nozzle


40


has a circular cross-sectional configuration as described above, closer to an end of the opening portion of the nozzle


40


in the width direction, smaller an opening state of the opening portion, namely, smaller a length of the opening portion of the nozzle


40


in the conveying direction. (a length of the opening portion in the conveying direction at a center of the opening portion is equal to the diameter D, and a length of the opening portion in the conveying direction at the end of the opening portion in the width direction is 0.) However, because the nozzles


40


neighboring each other in the conveying direction are arranged to be overlapped in the width direction by (¼)D from each end of the nozzles


40


in the width direction, unevenness of amount of the warm air blown onto the photosensitive material, caused by such configuration of the nozzles


40


, can be suppressed. Therefore, unevenness of drying state of the photosensitive material can be further suppressed. In the present embodiment, the nozzle


40


has a circle cross-sectional configuration, however, the nozzle


40


may has a ellipse cross-sectional configuration.




In the present embodiment, an opening rate of the nozzles


40


with respect to the horizontal portion


34


B is equal to or less than 50%. By this structure, namely, by suppressing the opening rate to be low, it is possible that a blowing speed (a wind velocity) of the drying air (the warm air) blown onto the photosensitive material through the nozzle


40


is equal to or more than a predetermined value. Because a drying speed (a time necessary for drying the photosensitive material) depends on the wind velocity of the warm air blown onto the photosensitive material, the drying speed can be improved by increasing the blowing speed of the warm air.




As shown in

FIG. 3

, the warm air, which is blown from the nozzles


40


formed on the guide plate


34


in above described manner to the conveying belt side, refluxes to the supplying path


42


in such a manner that the warm air passes through an endless belt


52


and a returning duct


54


. The endless belt


52


structuring the conveying belt


36


and formed by a mesh is wound between rollers


48


and


50


. The a returning duct


54


extends in the width direction.




As shown in

FIG. 4

, a plurality of ribs


56


A and ribs


56


B are disposed on the surface


35


A of the horizontal portion


34


B of the guide plate


34


in the conveying direction with a predetermined interval. Each rib


54


A extends so as to be inclined, from a substantially central portion of the guide plate


34


in the width direction to a one end of the guide plate


34


in the width direction, toward the downstream side of the conveying direction. Each rib


54


B is extends so as to be inclined, from a substantially central portion of the guide plate


34


in the width direction to the other end of the guide plate


34


in the width direction, toward the downstream side of the conveying direction. Thus, a plurality of pairs of the


6


and


6


are arranged in the conveying direction with the predetermined interval. The photosensitive material is curled in the width direction thereof in accompany with being dried. However, the ribs


56


A and ribs


56


B can suppress curled amount of the photosensitive material by moving tip ends of the curled photosensitive material A toward respective width directions. Accordingly, the ribs


56


A and ribs


56


B prevent the photosensitive material A from being damaged due to that the tip end of the photosensitive material A is caught by the nozzles


40


. Also, the ribs


56


A and ribs


56


B prevent the photosensitive material A from being jammed.




Next, the operation of thus structured processor


10


will be explained.




The sheet-like photosensitive material, in which latent images are formed by a printer (not shown in the drawings), is inserted into the developing section


14


, and immersed in the developing tank


20


, the fixing tank


22


and the washing tank


24


in order. Thus the images are fixed. Then, this wet photosensitive material is conveyed to the drying section


16


in a state in which image recording surface thereof faces bottom.




First, in the drying section


16


, the photosensitive material passes through the pairs of the squeeze rollers


30


and


32


, and extra water (most of the water) on the photosensitive material is removed, as shown in FIG.


2


. The photosensitive material which has passed through the pairs of the squeeze rollers


32


is guided by the inclined portion


34


A of the guide plate


34


, and then the photosensitive material enters into a region between the horizontal portion


34


B of the guide plate


34


and an endless belt


52


of the conveying belt


36


.




At this time, the photosensitive material is dried by the radiation heat from the guide plate


34


which is heated by the ceramic heaters


38


A and


38


B. Because the ceramic heaters


38


A and


38


B are structured so as to extend in the width direction, unevenness of amount of the radiation heat from the guide plate


34


which is heated in the width direction is suppressed. Namely, the radiation heat is uniformly, in the width direction, applied to the photosensitive material. Accordingly, non-uniformity of dried state of the photosensitive material by the radiation heat in the width direction is suppressed. Further, because the ceramic heater


38


A is disposed at the inclined portion


34


A and the ceramic heater


38


B is disposed at the horizontal portion


34


B in the vicinity of the inclined portion


34


A (at the inclined portion


34


A side), the largest amount of the radiation heat can be transmitted to the photosensitive material at a region in the vicinity of the pair of squeeze rollers


32


(at the pair of squeeze rollers


32


side), namely, at the upper stream side in the conveying direction, where the photosensitive material is in the most wet state. Accordingly, the drying efficiency is improved.




In particular, because the surface


35


A (the photosensitive material side surface) of the guide plate


34


which is made of aluminum is painted in black, and a total emissivity is made to be equal to or more than 0.9, amount of the radiation heat from the guide plate


34


becomes large. Accordingly, the photosensitive material can be dried efficiently.




When the photosensitive material reaches a position in which the photosensitive material faces the horizontal portion


34


B of the guide plate


34


, the photosensitive material is conveyed in a state in which the photosensitive material is attached to the endless belt


52


of the conveying belt


36


by the warm air blown from the nozzles


40


of the guide plate


34


toward the photosensitive material (toward the endless belt


52


), as shown in FIG.


3


. Accordingly, because the photosensitive material is conveyed in a state in which the image recording surface A


1


of the photosensitive material A is apart (spaced) from the guide plate


34


, the image recording surface A


1


of the photosensitive material A can be prevented from being scratched by sliding of the photosensitive material A and the guide plate


34


(the horizontal portion


34


B).




Further, at this time, the warm air blown onto the photosensitive material is a warm air which is heated by the heated


44


in the supplying path


42


, and further heated by the ceramic heaters


38


A and


38


B. Accordingly, because this warm air is heated by two heat sources, temperature of this warm air rises efficiently. Therefore, the drying is performed efficiently. Further, the warm air blown to the photosensitive material from the nozzles


40


passes through the endless belt


52


which is formed by the mesh, and returns to the supplying path


42


via the returning duct


54


. Namely, because it is structured that the warm air refluxes by the fan


46


being driven, after the temperature of the warm air reaches to a predetermined value, the temperature of the warm air is maintained at the predetermined value efficiently.




Further, for example, when the present embodiment is compared to a case in which a temperature sensor


72


(shown in

FIG. 3

by the dotted line) is provided at the supplying path


42


, because the heater


44


is feedback-controlled on the basis of the detected temperature detected by the temperature sensor


70


which is provided at the guide plate


34


in the present embodiment, a temperature, which is substantially equal to or nearer the temperature at a position in which the photosensitive material A is dried, can be detected. Therefore, accuracy of the feedback-controlling is improved. As a result, the photosensitive material can be dried with further higher temperature.




Further, the nozzles


40


formed in the horizontal portion


34


B of the guide plate


34


are arranged such that a nozzle


40


(for example, the nozzle


40


A in

FIG. 5

) and a nozzle


40


positioned to be offset with respect to the nozzle


40


A in the conveying direction (for example, the nozzle


40


B in

FIG. 5

) are disposed so as to be overlapped each other in the width direction by (¼)D. Accordingly, the warm air can be blown onto the photosensitive material in entire area in the width direction without non-uniformity. Therefore, unevenness of drying state in the width direction of the photosensitive material can be further suppressed.




Further, in the present embodiment, an opening rate of the nozzles


40


with respect to the horizontal portion


34


B of the guide plate is preferably equal to or less than 50%. By this structure, the blowing speed (wind velocity) of the drying air (warm air) is equal to or more than a predetermined value. Accordingly, drying efficiency which depends on the wind velocity of the warm air is improved.




Moreover, when the opening rate of the nozzles


40


becomes large, a distance between the openings of the nozzles


40


adjacent to each other becomes small. Therefore, strength of the guide plate (the horizontal portion


34


B) becomes small due to a thickness (corresponding to the distance) between the nozzles


40


adjacent to each other being small. Further, it becomes difficult to form the nozzles in the guide plate (the horizontal portion


34


B), for example, by a cutting die or the like, when the thickness between the nozzles


40


adjacent to each other is small. On the other hand, when the opening rate of the nozzles


40


becomes small, even if the blowing speed of the warm air from the nozzle


40


become faster, unevenness of drying state in the photosensitive material A may occur because the distance between the openings of the nozzles


40


adjacent to each other becomes large. Moreover, because amount of the warm air from the nozzle


40


becomes small, the drying efficiency becomes deteriorated. Accordingly, taking into consideration those, the opening rate of the nozzles


40


with respect to the horizontal portion


34


B is, more preferably, equal to or more than 2% and equal to or less than 10%.





FIG. 9

is a graph showing a relation between a drying rate and the opening rate in cases in which the diameter of the nozzle is 4.0 mm and 5.0 mm, which are selected by consideration of the drying characteristics. The drying rate is a value corresponding to the drying time which is necessary for the photosensitive material A being dried. Namely, smaller drying rate is preferable. It is clear from the

FIG. 9

that the drying rate becomes minimum value when the opening rate is between 6% and 7% in both cases in which the nozzle is 4.0 mm and the nozzle is 5.0 mm, namely the most optimum point (an optimum opening rate) in the each case exists between 6% and 7%. Accordingly, the opening rate of the nozzles


40


with respect to the horizontal portion


34


B is further preferably equal to or more than 6% and equal to or less than 7% in those cases.




Further, in accompany with that the photosensitive material is conveyed toward the conveying downstream side on the horizontal portion


34


B of the guide plate


34


by the conveying belt


36


, the photosensitive material A curls in the width direction thereof due to being dried (see FIG.


6


). As a result, end portions of the image recording surface A


1


of the photosensitive material in the width direction abut the guide plate


34


. However, because merely the end portions of the image recording surface A


1


contact (line-contact) to the guide plate


34


, namely, almost area of the image recording surface A


1


does not contact the guide plate


34


, the image recording surface A


1


is prevented from being scratched.




Further, as mentioned above, the tip ends


60


A and


60


B (hereinafter, corner portions) at the end portions in the width direction of the photosensitive material which is curled in the width direction are abut ribs


56


A and


56


B, as shown in FIG.


7


. Therefore, the corner portions


60


A and


60


B are guided along the respective ribs


56


A and


56


B such that the corner portions


60


A and


60


B move toward respective both end portions in the width direction of the guide plate. As the result, as shown in

FIG. 7

, angles between the corner portions


60


A and


60


B (see FIG.


6


), which substantially stood upright before being guided by the ribs


56


A and


56


B, with respect to the guide plate


34


in the width direction are made small. Accordingly, it can be surely prevented that the corner portions


60


A and


60


B are damaged, and/or the photosensitive material A is jammed, by that the corner portions


60


A and


60


B of the photosensitive material which is curled due to being dried are caught by the nozzles


40


when the photosensitive material is conveyed.




(Second Embodiment)




Next, a drying device relating to a second embodiment of the present invention will be described. The device relating this second embodiment is applied to an ink jet recording device. Note that portions which are the same as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted. Only portions which are different from the first embodiment will be described with reference to FIG.


8


.




As shown in

FIG. 8

, in the drying section


16


of the ink jet recording device


70


, ink drops from an ink jet printing head


76


are applied (put) on a paper B conveyed by pairs of conveying rollers


72


and


74


, therefore, the image is formed on the paper B. Hot air, which is from a blowing holes


40


, is blown onto an image recording surface of the paper B on which the image is formed by the ink drops. Further, the paper B can be dried efficiently by the radiating heat which is from the guide plate


34


.




In the drying device of the present invention, image recording medium can be dried efficiently.



Claims
  • 1. A drying device for drying a wet image recording medium conveyed on a conveying path, comprising:a plate member disposed along the conveying path, the plate member including blowing holes through which a wind for drying is blown onto the image recording medium and facing the conveyed image recording medium, wherein the plate member comprises a sloped portion and a horizontal portion, the horizontal portion being disposed parallel to the conveying path; a first heating device for directly heating the plate member, the heating device being disposed on or inside the plate member, wherein the first heating device is disposed on the sloped portion of the plate member; a second heating device disposed at a wind for drying supplying path, wherein the wind for drying supplying path supplies the wind for drying to the blowing holes of the plate member, the second heating device being disposed on the horizontal portion of the plate member, wherein the wind for drying is heated by both the first heating device and the second heating device.
  • 2. A drying device for drying a wet image recording medium conveyed on a conveying path, comprising:a plate member disposed along the conveying path, the plate member including blowing holes through which a wind for drying is blown onto the image recording medium and facing the conveyed image recording medium, wherein the plate member comprises a sloped portion and a horizontal portion, the horizontal portion being disposed parallel to the conveying path; a first heating device for directly heating the plate member, the heating device being disposed on or inside the plate member, wherein the first heating device is disposed on the sloped portion of the plate member; a second heating device disposed at a wind for drying supplying path, wherein the wind for drying supplying path supplies the wind for drying to the blowing holes of the plate member, the second heating device being disposed on the horizontal portion of the plate member, wherein the wind for drying is heated by both the first heating device and the second heating device, and wherein a total area of the blowing holes with respect to an area of the plate member is from approximately 2% to approximately 10%.
  • 3. A drying device according to claim 2, wherein at least a surface, which faces the image recording medium, of the plate member comprises a material having high emissivity.
  • 4. A drying device according to claim 2 further comprising a conveying member for conveying the image recording medium, the conveying member facing the plate member and being disposed such that the conveyed image recording medium is interposed between the plate member and the conveying member,wherein the image recording medium is conveyed in a state in which an image recording surface of the image recording medium faces the plate member, and the image recording medium is conveyed in a state in which the image recording medium is pressed in a direction of the conveying member by one of wind pressure of the wind for drying blown from the blowing holes and negative pressure of a blowdown side of the wind for drying, such that the image recording medium does not surface-contact the plate member.
  • 5. A drying device according to claim 2, wherein at least one rib is provided at a surface, which faces the image recording medium, of the plate member, the rib extending both downstream in a conveying direction of the image recording medium and laterally in a width direction, from a substantial center of the plate member toward a substantial width-direction edge of the plate member, the width direction being orthogonal to the conveying direction.
  • 6. A drying device according to claim 2, wherein portions of blowing holes overlap when viewed along the conveying direction, the blowing holes located in different positions in a conveying direction of the image recording medium and adjacent in a width direction of the plate member.
  • 7. A drying device according to claim 2, wherein a temperature sensor is disposed at the plate member.
Priority Claims (1)
Number Date Country Kind
2001-092522 Mar 2001 JP
US Referenced Citations (17)
Number Name Date Kind
1072512 Schewczik Sep 1913 A
3122427 Doleman Feb 1964 A
3771239 Minoda et al. Nov 1973 A
3800432 Miyata et al. Apr 1974 A
4551926 Aufderhaar Nov 1985 A
4622762 Reed Nov 1986 A
4932139 Lehtinen Jun 1990 A
5167080 Burkhardt et al. Dec 1992 A
5345061 Chanasyk et al. Sep 1994 A
5504271 Curtis et al. Apr 1996 A
5768799 Delaunay et al. Jun 1998 A
5847362 Sissons et al. Dec 1998 A
5902502 Sissons et al. May 1999 A
6006446 Pagendarm Dec 1999 A
6134811 Berger et al. Oct 2000 A
6351896 Vainio Mar 2002 B1
6463674 Meyers et al. Oct 2002 B1