JP2008189454A - Paper feeder and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper feeder capable of surely dehumidifying paper. <P>SOLUTION: The paper feeder 23 includes a paper feeding cassette 24 for storing the paper, a heat source 25, a fan 28 as a blowing means for blowing heat generated by the heat source 25 to the paper and a first and a second blowing ports 29a, 29b. Thus, the heat generated by the heat source 25 can be positively blown to the paper stored in the paper feeding cassette 24 by the fan 28 and the like. Hence, it is possible to surely dehumidifying the paper. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sheet feeding device and an image forming apparatus, and more particularly to a sheet feeding device capable of dehumidifying sheets stored in a sheet feeding cassette and an image forming apparatus including such a sheet feeding device.

  There are various environments in which the image forming apparatus including the paper feeding device is arranged. For example, the image forming apparatus may be arranged in a humid environment with high humidity. In such a case, the paper stored in the paper feeding device absorbs moisture in the air and absorbs moisture. If the sheet absorbs moisture, it may cause a double feed or the like when feeding the sheet, which may adversely affect the sheet. Further, if the paper absorbs moisture, it may be difficult to transfer the toner image onto the paper, and there is a possibility that an image cannot be formed appropriately. Therefore, when the paper in the paper feeder absorbs moisture, the paper needs to be dehumidified and dried.

Here, a technique related to a dehumidifying heater for dehumidifying the paper in the paper feeding device is disclosed in Japanese Patent Laid-Open No. 2002-167065 (Patent Document 1). According to Patent Document 1, a dehumidifying heater for dehumidifying paper is provided below the paper feed cassette, and warmed air is sent upward through a plurality of openings provided in the bottom plate of the paper feed cassette. In this way, the paper in the paper feed cassette is dehumidified uniformly.
Japanese Patent Laid-Open No. 2002-167065 (FIGS. 1, 15, etc.)

  Depending on the configuration of the paper feeding device, it may be difficult to provide a dehumidifying heater below the paper feeding cassette as in the technique disclosed in Patent Document 1. In such a case, the warmed air from the dehumidifying heater cannot be sent into the paper feed cassette. As a result, the paper cannot be positively dehumidified, and the paper in the paper feeding device remains in a state of moisture absorption. Therefore, as described above, there is a risk of adverse effects when feeding paper. There is also a possibility that an image cannot be formed appropriately.

  An object of the present invention is to provide a paper feeding device that can reliably dehumidify paper.

  Another object of the present invention is to provide an image forming apparatus capable of appropriately forming an image.

  A paper feeding device according to the present invention includes a paper feeding cassette for storing paper, a heat source, and a spraying means for spraying heat generated by the heat source onto the paper.

  Preferably, it includes a transport unit that transports heat to the paper feed cassette.

  Further, the conveying means has a temperature maintaining means for conveying while maintaining the temperature of heat.

  More preferably, the spraying means can change the spraying amount.

  More preferably, the heat source is a heat generating member provided in the paper feeding device.

  More preferably, it includes a humidity sensor for detecting the humidity in the sheet feeding device, and a control means for operating the spraying means if the humidity detected by the humidity sensor is higher than a predetermined value.

  More preferably, the spraying unit includes a sheet separating unit that sprays heat between the plurality of sheets to separate the sheets.

  More preferably, the paper feeding device includes an annular belt that has an opening and is in contact with the paper, a suction portion that is provided in the belt and sucks air, and a roller that rotates the belt. A suction feeding unit that sucks air by the suction unit to suck the paper and feeds the paper. Here, the spraying means sprays heat onto the paper from the opening.

  In another aspect of the present invention, an image forming apparatus includes any one of the above-described paper feeding devices.

  Preferably, the heat source is a heat generating member provided in the image forming apparatus.

  More preferably, the humidity sensor can detect humidity in the image forming apparatus.

  According to the present invention, the heat generated by the heat source can be positively sprayed onto the paper stored in the paper feed cassette by the spraying means. Therefore, it is possible to reliably dehumidify the paper.

  Also, according to such an image forming apparatus, it is possible to feed dehumidified paper, so that paper feeding in the image forming apparatus becomes smooth. Therefore, an image can be appropriately formed.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a digital multifunction peripheral 10 when an image forming apparatus including a paper feeder according to an embodiment of the present invention is applied to the digital multifunction peripheral 10. Referring to FIG. 1, a digital multifunction peripheral 10 displays a control unit 11 that controls the entire digital multifunction peripheral 10, a DRAM 12 for writing and reading image data and the like, and information that the digital multifunction peripheral 10 has. An operation unit 13 that includes a display screen and serves as an interface with the user in the digital multi-function peripheral 10, a document feeder 14 that automatically transports a document to a predetermined document reading position, and a document that has been transported by the document feeder 14 An image reading unit 15 that reads the image at a predetermined reading position with a scanner, an image forming unit 16 that forms the image from a document read by the image reading unit 15, a hard disk 17 that stores image data and the like, and a public A FAX communication unit 18 connected to the line 20 and a network IF (interface) for connecting to the network 21 And a part 19. In addition, the digital multifunction peripheral 10 includes a paper feeding device 23 that feeds paper to the image forming unit 16, a heat source 25 that generates heat, and a humidity sensor 26 that detects humidity in the digital multifunction peripheral 10. Examples of the heat source 25 include a fixing roller (not shown) that generates a large amount of heat in order to fuse the toner to the paper at a high temperature. In this case, the fixing roller operates as the heat source 25.

  The control unit 11 compresses and writes the original data supplied from the image reading unit 15 in the DRAM 12, reads the data written in the DRAM 12, decompresses and encodes the data, and outputs it by the image forming unit 16.

  The digital multi-function peripheral 10 operates as a copier by forming an image in the image forming section 16 via the DRAM 12 using the document read by the image reading section 15. Further, the digital multifunction peripheral 10 forms an image in the image forming unit 16 via the DRAM 12 using the image data transmitted from the personal computer 22 connected to the network 21 through the network IF unit 19, thereby serving as a printer. Operate. Further, the digital multifunction peripheral 10 forms an image in the image forming unit 16 through the DRAM 12 using the image data transmitted from the public line 20 through the FAX communication unit 18, and also by the image reading unit 15. The image data of the read original is transmitted to the public line 20 through the FAX communication unit 18 to operate as a facsimile machine.

  In FIG. 1, thick arrows indicate the flow of image data, and thin arrows indicate the flow of control signals or control data.

  Here, a specific configuration of the paper feeding device 23 will be described. FIG. 2 is a schematic cross-sectional view showing the paper feeding device 23 provided in the digital multifunction peripheral 10. Referring to FIGS. 1 and 2, the paper feeding device 23 includes a plurality of paper feeding cassettes 24 for storing paper to be output. The paper feed cassette 24 can store a plurality of sheets of various sizes.

  The paper feeding device 23 is a fan 28 serving as a blowing means for blowing heat generated from a heat source 25 such as a fixing roller onto paper stored in the paper feeding cassette 24, a first blowing port 29a, and a second blowing. Includes mouth 29b. By rotating the fan 28, the heat generated from the heat source 25 can be sprayed from the first and second spray ports 29a and 29b to a predetermined portion of the sheet. The first blowing port 29 a is provided at a position where the first blowing port 29 a is blown between the uppermost sheet and the sheet immediately below it among the plurality of sheets stored in the sheet feeding cassette 24. By providing the first spray port 29a at such a position, the uppermost sheet can be lifted up when heat is sprayed. The second spray port 29b is provided on the lower side of the first spray port 29a. By providing the second blowing port 29b at such a position, a plurality of sheets stored in the sheet feeding cassette 24 can be separated. That is, the paper feeding device 23 includes a second spraying port 29b as a paper separating unit that sprays heat between a plurality of papers to separate the papers.

  The sheet feeding device 23 includes a duct 27 and a fan 28 serving as a conveying unit that conveys heat generated by the heat source 25, specifically, heated air generated by a fixing roller operating as the heat source 25 to the sheet feeding cassette 24. Including. That is, the heat generated by the heat source 25 is conveyed to the paper feed cassette 24 by the duct 27 and the fan 28 as conveying means. The duct 27 extends from a position where the heat source 25 is provided to a position where the paper feed cassette 24 is provided. The fan 28 is provided at a predetermined location of the duct 27. By operating the fan 28, the heat in the duct 27 can be conveyed in the direction of arrow A in FIG. 2 and sprayed onto the paper from the first and second spray ports 29a, 29b. The duct 27 and the fan 28 can be provided by freely designing the shape, arrangement, quantity and the like according to the configuration of the paper feeding device 23.

  Further, the paper feeding device 23 is provided with a paper suction device 31 as suction feeding means. The sheet adsorbing device 31 adsorbs the sheet by suction from the opening, and feeds the sheet by this. FIG. 3 is a view of a part of the sheet suction device 31 as seen from the direction indicated by the arrow III in FIG. 2 and 3, the sheet adsorbing device 31 has a plurality of openings 35 and has an annular belt 32 that comes into contact with the sheet, and a suction unit 34 that is provided in the belt 32 and sucks air. And rollers 33a and 33b for rotating the belt 32. The suction unit 34 sucks air through the opening 35 to suck the paper and feeds the paper. In such a sheet suction device 31, only the uppermost sheet among a plurality of sheets stored in the sheet feeding cassette 24 can be sucked and fed. Therefore, it is possible to easily separate and feed only the uppermost sheet from a plurality of sheets. In this case, since the uppermost sheet is lifted by the first outlet 29a, the uppermost sheet can be fed more easily.

  Here, a case where the digital multifunction peripheral 10 dehumidifies the paper will be described. FIG. 4 is a flowchart showing the operation of the control unit 11 when dehumidifying the paper. The case where the paper is dehumidified will be described with reference to FIGS.

  First, the humidity in the digital multi-function peripheral 10 is detected by the humidity sensor 26 (in FIG. 4, step S11, hereinafter, steps are omitted). Next, it is determined whether or not the humidity detected by the humidity sensor 26 is higher than a predetermined value (S12). If the humidity is higher than the predetermined value (YES in S12), the spraying means is activated. Here, the control unit 11 operates as control means. Specifically, the heat generated from the heat source 25 is conveyed to the paper feed cassette 24 by the duct 27 and the fan 28 (S13). Then, heat is sprayed onto the paper through the first and second spray ports 29a and 29b (S14). In this way, the paper is dehumidified.

  With this configuration, the heat generated by the heat source 25 can be positively sprayed onto the paper stored in the paper feed cassette 24 by the fan 28 and the first and second spray ports 29a and 29b. it can. Therefore, it is possible to reliably dehumidify the paper.

  Further, according to such a digital multi-function peripheral 10, since the dehumidified paper can be fed, the possibility of causing double feeding of the paper is reduced, and the transport of the paper in the digital multi-function peripheral 10 becomes smooth. . Further, the toner image visualized from the electrostatic latent image in the image forming unit 16 can be reliably transferred to the paper. Therefore, an image can be appropriately formed.

  In this case, since heat is transferred to the sheet cassette 24 by the duct 27 and the fan 28, there is no space for providing a dehumidifying heater or the like in the vicinity of the sheet cassette 24, and the heat source 25 is located away from the sheet cassette 24. However, heat can be conveyed appropriately. Therefore, the paper can be dehumidified more efficiently.

  Further, since the heat is sprayed from the first spraying port 29a, the sheet can be dehumidified while the sheet is lifted. Therefore, it is possible to dehumidify when the uppermost sheet is sucked and fed. Furthermore, since heat is sprayed from the second spraying port 29b, the sheet can be dehumidified while separating the sheet.

  After the spraying of heat, it is determined whether or not the dehumidification of the paper is completed (S15). If the dehumidification is completed (YES in S15), the spraying of heat is terminated (S16). Completion of dehumidification is determined by, for example, whether or not the above-described spraying means has been sprayed for a predetermined time, or whether or not the humidity has become below a predetermined value by the humidity sensor 26.

  Further, at a timing when paper feeding is not performed, heat may be blown from the plurality of openings 35 provided in the belt 32 of the paper suction device 31 described above. By doing so, the entire sheet can be dehumidified more efficiently.

  In the above embodiment, the first and second spray ports 29a and 29b and the opening 35 are adapted to spray heat to a predetermined portion of the sheet. It is good also as a structure which can be sprayed to arbitrary places. For example, the sheet feeding cassette 24 can be raised and lowered, and the sheet feeding cassette 24 is raised and lowered while heat is blown from the first and second blowing ports 29 a and 29 b and the opening 35. If it does so, the location sprayed will change. In this way, heat is sprayed on any part of the paper. By doing so, heat can be sprayed on the entire sheet stored in the sheet feeding cassette 24. Then, the paper can be dehumidified as a whole, and the paper can be dehumidified more appropriately. In this case, by providing the opening 35a that blows heat and the opening 35b that blows normal air among the plurality of openings 35, it is possible to adjust the blowing amount, temperature, and the like.

  Further, the first and second spray ports 29a and 29b and the opening 35 may be configured to change the spray amount. By doing so, the spraying amount can be changed according to the moisture absorption state of the paper, and dehumidification can be performed appropriately. In this case, specifically, for example, the amount of spraying can be changed by changing the rotation speed of the fan 28 or changing the area of the first spraying port 29a. Furthermore, it is good also as a structure which sprays heat from either one of the 1st or 2nd spraying ports 29a and 29b according to a condition.

  In the above embodiment, the heat generating member such as the fixing roller included in the digital multi-function peripheral 10 is used as the heat source 25. However, the present invention is not limited to this. A heat generating member may be used as a heat source. Further, the heat generating member in the paper feeding device 23 can be used as the heat source 25. Furthermore, a heat source such as a heater may be newly provided in the paper feeding device 23 and the digital multifunction peripheral 10. In this case, the heater can be provided at an appropriate position in accordance with the configuration of the paper feeder 23 and the like.

  Moreover, you may comprise the duct 27 so that it may have a temperature maintenance means to convey, maintaining a predetermined temperature of heat. Specifically, the outer portion of the duct 27 is covered with a heat insulating material, or the heat source 25 closer to the paper feed cassette 24 among the plurality of heat sources 25 is selected and conveyed. Moreover, it is good also as a structure which conveys heat from the several heat source 25. FIG. By carrying out like this, it can convey, maintaining predetermined temperature, without reducing the temperature of the heat generated from the heat source 25 more than necessary. Therefore, the paper can be efficiently dehumidified.

  In the above-described embodiment, the paper feeding device 23 includes the paper suction device 31. However, the present invention is not limited thereto, and may be configured to include a paper feeding roller for feeding paper.

  Further, in the above-described embodiment, it is determined whether or not the spraying means can be operated according to the humidity detected by the humidity sensor 26 provided in the digital multi-function peripheral 10, but the present invention is not limited to this. For example, whether or not the spraying means can be operated may be determined when the spraying means is periodically operated, when a sheet is replaced, when a predetermined operation is performed, or the like. Further, a humidity sensor may be provided in the sheet feeding device 23, and it may be determined whether or not the spraying means can be operated according to the detected humidity. Further, the humidity may be detected using a humidity sensor provided in a general image forming unit 16.

  Note that the above configuration may be configured such that a spraying means for spraying heat or the like can be selected in accordance with the standby state or the image forming state of the digital multifunction peripheral 10. For example, heat may be sprayed from the opening 35 of the sheet suction device 31 in the standby state, and heat may be sprayed from the first and second spray ports 29a and 29b in the image forming state.

  In the above embodiment, the paper feeding device 23 is provided inside the digital multifunction peripheral 10. However, the present invention is not limited to this, and the paper feeding device 23 is provided outside the digital multifunction peripheral 10. Also good. Further, the sheet feeding device 23 may be detachable from the digital multifunction peripheral 10.

  In the above-described embodiment, the case where copying is performed by the digital multi-function peripheral 10 has been described. The

  As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to the thing of embodiment shown in figure. Various modifications and variations can be made to the illustrated embodiment within the same range or equivalent range as the present invention.

1 is a block diagram showing an overall configuration of a digital multifunction peripheral according to an embodiment of the present invention. 1 is a schematic cross-sectional view of a paper feeding device provided in a digital multifunction peripheral. FIG. 3 is a view of a part of the sheet suction device 31 as viewed from the direction indicated by an arrow III in FIG. 2. It is a flowchart which shows operation | movement of the control part at the time of dehumidifying a paper.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Digital multifunction device, 11 Control part, 12 DRAM, 13 Operation part, 14 Document feeder, 15 Image reading part, 16 Image formation part, 17 Hard disk, 18 FAX communication part, 19 Network IF part, 20 Public line, 21 Network , 22 PC, 23 paper feeding device, 24 paper feeding cassette, 25 heat source, 26 humidity sensor, 27 duct, 28 fan, 29a first air outlet, 29b second air outlet, 31 paper suction device, 32 belt, 33a , 33b Roller, 34 Suction part, 35, 35a, 35b Opening part.

Claims (11)

A paper cassette for storing paper,
A heat source,
And a spraying unit that sprays heat generated by the heat source onto the sheet. The sheet feeding device according to claim 1, further comprising a conveying unit configured to convey the heat to the sheet feeding cassette. The sheet feeding device according to claim 2, wherein the transport unit includes a temperature maintaining unit that transports the heat while maintaining a predetermined temperature. The sheet feeding device according to claim 1, wherein the spraying unit is capable of changing a spraying amount. The sheet feeding device according to claim 1, wherein the heat source is a heat generating member provided in the sheet feeding device. A humidity sensor for detecting humidity in the paper feeding device;
The sheet feeding device according to claim 1, further comprising a control unit that activates the spraying unit when the humidity detected by the humidity sensor is higher than a predetermined value. The sheet feeding device according to claim 1, wherein the spraying unit includes a sheet separating unit that sprays the heat between the plurality of sheets to separate the sheets. The sheet feeding device includes an opening, an annular belt that comes into contact with the sheet, a suction unit that is provided in the belt and sucks air, and a roller that rotates the belt. A suction paper feeding means for sucking air by sucking the air through the suction section and feeding the paper;
The sheet feeding device according to claim 1, wherein the spraying unit sprays the heat onto the sheet from the opening. An image forming apparatus comprising the paper feeding device according to claim 1. The image forming apparatus according to claim 9, wherein the heat source is a heat generating member provided in the image forming apparatus. The image forming apparatus according to claim 9, wherein the humidity sensor is capable of detecting humidity in the image forming apparatus.

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