JPH09160206A - Sheet heating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten rise time for heating a sheet. SOLUTION: A slender surface heating element 51 is wound round a carrying roller 50 having a cylindrical outer surface, and its one end side 51a in the length direction is fixed and its other end side 51b is pulled by a coil spring 60, then its inner surface is pressed against the outer surface of the roller 50. By feeding power so that the heating element 51 may generate heat, driving force from a driving source is transmitted to drive and rotate the roller 50. A sheet S inserted between the roller 50 and the heating element 51 is heated by the heating element 51 while it is carried with the rotation of the roller 50.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention can be applied to a sheet recording apparatus such as a copying machine, a printer, a facsimile, and a printing machine, which records on a sheet such as a sheet of paper or an envelope. For more information,
In such a sheet recording apparatus, the present invention relates to a sheet heating apparatus that heats and conveys a sheet to perform, for example, development, image fixing, and drying.

[0002]

2. Description of the Related Art Conventionally, in this type of sheet heating apparatus, a rod-shaped heating element such as a halogen lamp or a ceramic heater is provided at the center of a rotating cylinder, and a belt is rotatably wound on the outer surface of the rotating cylinder. There is one that is configured to rotate.

Then, for example, when developing, fixing an image, drying, etc., the belt is driven to rotate and the rotary cylinder is driven to rotate, and the heating element generates heat. The heat indirectly heats the rotary cylinder, and the belts are heated. The sheet placed between the rotating cylinder and the rotating cylinder was heated while being conveyed by the rotating cylinder.

However, in such a sheet heating device,
Since the heat generated by the heating element is transferred to the rotating cylinder through the air, it takes a long time to start heating the sheet.

Therefore, in order to shorten the rise time of sheet heating, a conventional sheet heating apparatus has a structure in which a sheet heating element is fixed to the inner surface of a rotary cylinder with an adhesive (Japanese Patent Laid-Open No. 63-63). No. 228155), and a configuration in which the heating element generates heat to warm up while the rotational drive of the belt is stopped (see Japanese Patent Laid-Open No. 1-214853).

[0006]

However, in such a conventional sheet heating apparatus, the heating cylinder heats the rotating cylinder and the rotating cylinder heats the sheet. Therefore, the rise time of the sheet heating is not so long. There was a problem that could not be shortened.

Therefore, an object of the present invention is to provide a sheet heating apparatus capable of shortening the rise time of sheet heating.

[0008]

Therefore, a sheet heating apparatus according to a first aspect of the present invention includes a rotating body having a cylindrical outer surface such as a conveyance roller 50 and a longitudinal direction, as shown in the following illustrated embodiment, for example. A sheet which is formed by an elongated sheet heating element 51 which is pulled to the inner surface to press the cylindrical outer surface of the rotating element and which transmits a driving force to the rotating element and is inserted between the sheet and the sheet heating element 51. It is characterized in that S is heated and conveyed.

Further, in the sheet heating apparatus according to the first aspect, when the sheet S is conveyed, the sheet S is directly heated by the sheet heating element 51.

According to a second aspect of the present invention, for example, as shown in the following illustrated embodiment, in the sheet heating apparatus 45 according to the first aspect, the planar heating element 51 has a positive temperature characteristic. It is characterized by

According to the second aspect of the invention, when the sheet heating element 51 reaches a predetermined temperature while heating the sheet S, the resistance value increases thereafter and the current stops flowing.

According to a third aspect of the present invention, for example, as shown in the following illustrated embodiment, in the sheet heating device 45 according to the first aspect, at least one end side of the planar heating element 51 in the longitudinal direction is provided. It is characterized by being removable.

According to the third aspect of the invention, when the sheet S is jammed between the rotating body and the sheet heating element 51, one end of the sheet heating element 51 in the longitudinal direction is removed to rotate the sheet. The pressing of the sheet heating element 51 against the is released.

According to a fourth aspect of the present invention, for example, as shown in the following illustrated embodiment, in the sheet heating device 45 according to the first aspect, at least one end side of the planar heating element 51 in the longitudinal direction is provided. It is characterized by being movable.

Further, in the invention according to claim 4, when the sheet S is jammed between the rotating body and the sheet heating element 51, the sheet heating element 51 is moved by rotating one end side in the length direction of the sheet heating element 51 and rotated. The pressing of the sheet heating element 51 against the body is released.

According to a fifth aspect of the present invention, for example, as shown in the following illustrated embodiments, in the sheet heating device 45 according to the first aspect, a plurality of the rotating bodies are provided, and one sheet is provided for each of the rotating bodies. It is characterized in that it is formed by pressing the sheet heating element 51.

According to the fifth aspect of the present invention, when the sheet S is heated and conveyed, the steam generated from the sheet S escapes through between the rotating bodies.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 4 shows an overall schematic configuration of the diazo copying machine.

This diazo copying machine, as shown by the dotted line,
A paper feed unit A is provided on the lower left side of the apparatus main body 10, and the paper feed unit A
Is provided on the right side of the exposure section B, the separation / conveyance section C is provided on the upper left side of the exposure section B, and the development section D is provided on the upper right side of the separation / conveyance section C.

The paper feed section A is provided with an original manual feed table 13 on the upper side, and a paper feed cassette 14 accommodating a sheet S which is a photosensitive paper is attached on the lower side thereof. A document transport path 15 is provided in the transport direction on the right side of the drawing from the document manual feed table 13.
Then, the merging / conveying path 16 is linearly provided. In the document transport path 15, the first feed roller pair 17,
The detection means 18 and the first stopper 19 are arranged respectively.
Further, a sheet conveying path 20 is provided in the right side of the drawing from the paper feeding cassette 14 in the paper feeding direction. The sheet conveying path 20
Is connected to the confluent transport path 16.

Then, the document P is inserted from the manual document feeding table 13 into the document conveying path 15 through the first feed roller pair 17 which is slightly separated in advance. Then
The document P is detected by the detection means 18, and the retractable first stopper 19 blocking the document transport path 15 is retracted, and the first feed roller pair 17 is brought into pressure contact with the document P to rotate it. It is conveyed to the confluent conveyance path 16 through the conveyance path 15. At the same time, the sheet feeding roller 21 is rotated to send out the sheet S from the sheet feeding cassette 14.
Then, the sheet P is conveyed to the merging / conveying path 16 through the sheet conveying path 20, and is merged with the original P to be superposed. afterwards,
The original P and the sheet S are passed through the second feed roller pair 22 which are separated from each other in advance, and are brought into contact with the second stopper 23 which can freely retract and retract, and the leading ends thereof are aligned. Then, the second stopper 23 is retracted, and the overlapped sheet S and document P are exposed by the second feed roller pair 22 in the pressure contact state.
Send to.

In the exposure part B, a transparent cylinder glass 26 containing a plurality of fluorescent lamps 25 is rotatably provided.
A driving roller 27 and a plurality of driven rollers 28 are arranged around the cylinder glass 26, an endless belt 29 is stretched between the rollers 27, 28, and the endless belt 29 is pressed against the outer peripheral surface of the cylinder glass 26. .

Then, the fluorescent lamp 25 is turned on, the sheet S and the original P are inserted between the cylinder glass 26 and the endless belt 29, and the sheet S and the original P are exposed while being sandwiched between them and conveyed, with the light energy of the fluorescent lamp 25. Sheet S
A latent image is formed thereon. Then, the exposed sheet S and original P are sent to the separation / conveyance unit C.

The separating / conveying section C has a pick-off plate 32 whose one end is pressed against the outer peripheral surface of the cylinder glass 26, and has suction fans (not shown) on the left and right sides of the conveying path 33 in the figure, respectively. Means 34 and sheet suction means 35 are provided. The document suction means 34 is
A transport belt 38 is stretched between the drive-side transport roller 36 and the driven-side discharge roller 37.

Then, the sheet S and the document P that have exited the exposure section B are guided to the conveyance path 33 of the separation / conveyance section C by the pick-off plate 32. Then, while the document P is sucked by the document suction means 34, the sheet S is sucked by the sheet suction means 35.
Is sucked to separate the original P and the sheet S. Then, one of the separated originals P is conveyed by the conveyance belt 38 and the original discharge rollers 39 pressed against the original to a document discharge tray 40.
Discharge up. The other sheet S is the sheet conveying roller 4
1 and the intermediate transfer roller pair 42 and the like to convey to the developing section D.

The developing section D is equipped with the sheet heating device 45 according to the first aspect. Then, the sheet S is heated by the sheet heating device 45 while being conveyed to develop the latent image. After the development, a pair of paper ejection rollers 46 is used for the copy tray 47.
The document P is discharged to the upper side, and the copy of the original P is completed.

Now, the sheet heating apparatus 4 according to claim 1
As shown in FIG. 1, the reference numeral 5 includes a conveyance roller 50 which is a rotating body having a cylindrical outer surface. The transport roller 50 is
It is made of metal and is rotatably supported at both ends by side plates, and the driving force from the driving source is transmitted to one end thereof.

An elongated sheet heating element 51 is provided on the outer periphery of the conveying roller 50. As shown in FIG. 2, the planar heating element 51 uses two heat-resistant films such as polyimide resin, and the first electrode 5 is formed on the inner surface of the one film.
3 and the second electrode 54 and the heating element 55 are printed and then pasted together.

The first electrode 53 and the second electrode 54
As shown in the drawing, each of the
54a and electrode portion 53b extending from the electrode 54b in a comb shape
・ Made with 54b, facing each other, and electrode part 53b
54b are alternately provided in parallel, and both energization parts 53
The c-54c is provided at one corner of the sheet heating element 51, and the lead wire 58 is connected thereto.

As the heating element 55, a member having a positive temperature characteristic such as carbon particles is used, and as indicated by hatching in FIG. 2, the electrode portion 53b of the first electrode 53 and the second electrode 53b.
It is provided so as to cover the electrode portion 54b of the electrode 54, and is provided in parallel with the first electrode 53 and the second electrode 54 as shown in FIG. When a part of the temperature decreases, the resistance value of a part of the temperature decreases, and the electric current flows only in that part, so that the heat can be regenerated.

Then, as shown in FIG. 1, one end 51a in the length direction of the sheet heating element 51 constructed as described above is appropriately fixed through the bracket 57, while the outer surface of the conveying roller 50 and the guides are fixed. It is wound around the outer surface of the roller 59, and the other end 51b in the length direction is pulled in the length direction by a coil spring 60 to press the inner surface of the sheet heating element 51 against the outer surface of the transport roller 50.

In the sheet heating device 45 described above, when the main switch of the illustrated diazo copying machine is turned on, power is supplied from the lead wire 58 to heat the planar heating element 51 and transmit the driving force from the driving source. Then, the transport roller 50 is rotationally driven in the counterclockwise direction shown by the arrow in the figure.

Then, the sheet S sent out from the separating / conveying section C is inserted between the conveying roller 50 and the sheet heating element 51, and the sheet S is conveyed while the conveying roller 50 is rotated. The sheet-like heating element 51 applies high heat to the sheet S to develop the latent image.

During such development, if the temperature of the sheet heating element 51 rises above a predetermined temperature, the resistance value increases due to the positive temperature characteristic and the current stops flowing. Thereby, the sheet heating element 51
It is possible to prevent the temperature from rising excessively.

In the illustrated sheet heating device 45, one end 51a in the lengthwise direction of the sheet heating element 51 is fixed at the upstream side in the sheet conveying direction, and the other end 51b in the lengthwise direction at the downstream side in the sheet conveying direction is a coil spring 60. Pulled with. But,
As shown in FIG. 5, one end side 5 in the length direction of the planar heating element 51
1a may be pulled on the upstream side in the sheet conveying direction using the coil spring 60, and the other end 51b in the length direction may be fixed on the downstream side in the sheet conveying direction.

In the sheet heating device 45 described above,
At least one end side of the planar heating element 51 in the length direction was pulled by using the coil spring 60. However, the present invention is not limited to this. For example, as shown in FIG.
An elastic member 64 such as a sponge or rubber having heat resistance is attached to one surface 62a of the second member 2, and the other end side 51b in the length direction of the sheet heating element 51 is fixed to the other surface 62b. May be wound around the outer surface of the elastic member 64. Then, the elasticity of the elastic member 64 pulls the other end side 51b of the planar heating element 51 in the length direction.

Furthermore, in the above-described sheet heating device 45, the lengthwise one end 51a and the lengthwise other end 51b of the planar heating element 51 are not removed. But,
At least one end side in the length direction of the planar heating element 51 may be detachable. That is, as shown in FIG. 7, the third bracket 63 for fixing the other end 51 b of the planar heating element 51 in the length direction and the elastic member 64 is detachably attached to the second bracket 62 with the thumbscrew 66.

When the sheet S is jammed between the sheet heating element 51 and the transport roller 50 during development, the thumbscrew 66 is loosened, and the second bracket 62 to the third bracket 6 are released.
7 is removed to bring it into the state shown by the chain double-dashed line in FIG. 7, and the pressing of the sheet heating element 51 against the transport roller 50 is released. As a result, the jammed paper can be easily removed.

Further, at least one end side of the planar heating element 51 in the length direction may be movable. That is, as shown in FIG. 8, the opening / closing member 68 has a plate shape in which the lengthwise intermediate portion is bent substantially at a right angle, and one end side 68 thereof is formed.
An inner winding portion 68b is provided on a, and the other end side 68c is provided rotatably around a fulcrum 69. And the sheet heating element 51
Winding the other end side 51b in the length direction of the inner winding portion 38b,
It is attached to one end side 68a of the opening / closing member 68 via a coil spring 70.

Then, in a normal state, the opening / closing member 68 is closed as shown in the figure, and the other end 51b in the length direction of the sheet heating element 51 is pulled by a coil spring 70 to press the inner surface against the outer surface of the conveying roller 50. It becomes.

On the other hand, at the time of development, when the sheet S is jammed between the sheet heating element 51 and the conveying roller 50, the opening / closing member 68 is rotated clockwise about the fulcrum 69 so that the two-dot chain line in FIG. , The sheet heating element 51 is moved toward the other end 51b in the length direction of the sheet heating element 51 to move the sheet heating element 5 with respect to the conveyance roller 50.
Release the pressing of 1. As a result, the jammed paper can be easily removed.

Furthermore, in all the sheet heating devices 45 described above, one conveying roller 50 is provided, and the sheet heating element 51 is pressed against the conveying roller 50. However, the present invention is not limited to this. For example, as shown in FIG. 9, two transport rollers 50 may be provided, and one sheet heating element 51 may be pressed against these transport rollers 50.
As shown in FIG. 0, three transport rollers 50 may be provided, and one sheet heating element 51 may be pressed against these transport rollers 50.

At the time of development, the steam generated from the sheet S is heated and conveyed while escaping through the gaps between the plurality of rotating bodies 50. This makes it possible to prevent uneven development due to water vapor.

In the above-described illustrated embodiment, the sheet heating apparatus used when developing the sheet S on which a latent image is formed by exposure is described. However, the present invention is not limited to this, and although not shown, the sheet heating device of the present invention is similarly used when fixing a transfer image transferred to a sheet or drying a sheet immersed in a liquid, for example. be able to.

[0045]

As described above, according to the invention described in claim 1, since the sheet is directly heated by the sheet heating element, the sheet heating is performed as compared with the conventional one in which the sheet is heated through the rotating cylinder. The rise time of can be shortened.

According to the second aspect of the present invention, when the sheet heating element is heated, when the temperature rises above a predetermined temperature, the resistance value increases and the current stops flowing. It is possible to prevent rising and increase safety.

When the sheet is jammed between the rotating body and the sheet heating element, according to the third aspect of the invention, one end of the sheet heating element in the length direction is removed and pushed to the rotating body. According to the invention of claim 4, the contact is released, and one end side of the planar heating element in the length direction is moved to release the pressing against the rotating body, thereby facilitating the removal of the jammed paper. can do.

According to the fifth aspect of the present invention, when the sheet is heated and conveyed, the steam generated from the sheet escapes through the gap between the rotating bodies, so that uneven development due to the steam can be prevented. it can.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a sheet heating apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view of a sheet heating element used in the sheet heating apparatus.

FIG. 3 is a circuit diagram thereof.

FIG. 4 is an overall schematic configuration diagram of an internal mechanism of a diazo copying machine including the sheet heating device.

FIG. 5 is a schematic configuration diagram of a sheet heating apparatus according to another embodiment.

FIG. 6 is a schematic configuration diagram of a sheet heating apparatus according to still another embodiment.

FIG. 7 is a schematic configuration diagram of a sheet heating apparatus according to still another embodiment.

FIG. 8 is a schematic configuration diagram of a sheet heating apparatus according to still another embodiment.

FIG. 9 is a schematic configuration diagram of a sheet heating apparatus according to still another embodiment.

FIG. 10 is a schematic configuration diagram of a sheet heating apparatus according to still another embodiment.

[Explanation of symbols]

 45 sheet heating device 50 transport roller (rotating body) 51 planar heating element S sheet

Claims (5)

[Claims] 1. A rotary body having a cylindrical outer surface, and an elongated planar heating element that pulls in the length direction to press the inner surface against the cylindrical outer surface of the rotary body, and transmits a driving force to the rotary body. A sheet heating device that heats and conveys a sheet inserted between the sheet heating element and the sheet heating element. 2. The sheet heating apparatus according to claim 1, wherein the sheet heating element has a positive temperature characteristic. 3. The sheet heating apparatus according to claim 1, wherein at least one end side in the length direction of the planar heating element is removable. 4. The sheet heating apparatus according to claim 1, wherein at least one end side in the length direction of the planar heating element is movable. 5. The sheet heating apparatus according to claim 1, wherein a plurality of the rotating bodies are provided, and one sheet-shaped heating element is pressed against the rotating bodies.