JP2008150167A - Image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To feed recording paper into a casing properly one by one even if the recording paper is thick in an image forming device. <P>SOLUTION: This image forming device comprises a feed tray 2 into which recording paper P is so loaded as to be rested there against and a friction pad 21 so disposed that the end of the recording paper P abuts on the paper passing surface 6a of the casing 6. The friction pad 21 is formed of a rubber member having an upstream 21s and a downstream 21h different from each other in the feeding direction F of the recording paper P, i.e, by a two-color molding. The downstream 21h is formed of a resin higher in hardness than a resin used for the upstream 21s. When the recording paper PO fed by the contact of the feed roller thereon among the recording paper P is brought into slide-contact with the downstream 21h of the friction pad 21, the recording paper PO is liable to be slid in the feeding direction F because a resistance force in the feeding direction F is small. Consequently, since the recording paper PO is easily separated by one sheet from the other recording paper P, the recording paper P can be fed one by one into the casing 6. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image forming apparatus that feeds recording sheets loaded in a sheet feeding tray one by one into a housing and forms an image on the recording sheets.

  2. Description of the Related Art Conventionally, in a small image forming apparatus, a paper feed tray in which a recording paper placing surface is inclined toward a housing is used. In such an image forming apparatus, the recording sheet is fed into the housing while changing the posture of the recording sheet along the sheet surface substantially horizontally from the state of being leaned on the sheet feeding tray. For example, in the image forming apparatus disclosed in Patent Document 1, a plurality of recording sheets are held in a sheet feeding tray and loaded into the sheet feeding tray in order to feed the recording sheets one by one into the housing. A friction pad is provided so as to come into contact with the leading end of the recording paper. Since the recording paper is leaned against the paper feed tray in contact with the friction pad, the friction force acts between the leading edge of each recording paper and the friction pad, so that the recording paper is held in the paper feed tray. Until maintained. When the recording paper is fed, for example, a force is applied to the uppermost of the loaded recording papers in the paper feeding direction, and the recording paper is bent and slidably contacted on the friction pad. The recording paper is separated from other recording paper loaded in the printer, and only the recording paper is fed into the housing.

  However, even when the friction pad is provided as described above, for example, when recording paper having a large thickness such as photo paper or recording paper having a strong stiffness is used, the recording paper is separated into only one sheet. There is a problem that it becomes difficult to do. That is, since such a recording sheet is difficult to bend, it is difficult to separate a recording sheet to be fed from another recording sheet, and a plurality of sheets can be simultaneously fed or one sheet cannot be fed. May fail. The solution of such a problem is not considered in the above-mentioned Patent Document 1.

Patent Documents 2 and 3 show the structure of an image reading apparatus that feeds recording sheets one by one by a paper feed roller and a separation pad arranged to face the paper feed roller. In the image reading apparatus disclosed in Patent Document 2, process oil is added to the paper feed roller, and the separation pad is made oil resistant to prevent abnormal noise. Further, in the image reading apparatus disclosed in Patent Document 3, the back surface of the friction sheet in the nip portion is configured by using two types of materials, that is, an elastic member and a hard member integrated with the mount, thereby preventing double feeding. It is improving. However, in the configuration shown in Patent Document 2 or Patent Document 3, the recording paper is fed between the paper feeding roller and the separation pad and then the paper feeding roller is rotated to feed the recording paper. This is not a paper to feed the recording paper one by one while sliding the recording paper against the friction pad, but there are problems such as a large number of parts, a complicated configuration, and an increase in manufacturing cost. Therefore, it cannot be applied as a solution to the above problem.
Japanese Patent Laid-Open No. 2003-40471 Japanese Patent Laid-Open No. 11-35182 JP-A-9-124174

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus that can appropriately feed various recording sheets one by one into a housing.

  In order to achieve the above object, the invention according to claim 1 is provided on the rear side of the housing and the recording paper, and the recording paper is stood and loaded in a state where the front end of the recording paper is in contact with the housing. A paper feed tray, a friction pad made of a rubber member attached to the housing and arranged to contact the leading end of the recording paper loaded in the paper feed tray, and a recording loaded in the paper feed tray A paper feed roller that rotates in contact with the uppermost recording paper of the paper and feeds the recording paper substantially horizontally into the housing while being in sliding contact with the friction pad; An image is formed by a conveying unit that conveys the recording sheet fed by the roller inside the housing, an image forming unit that forms an image on the recording sheet that is conveyed by the conveying unit, and the image forming unit. Paper discharge means for transporting the recorded paper outside the device, A paper discharge tray for receiving the recording paper conveyed by the paper discharge means and discharged to the outside of the casing; and the paper supply means, the image forming means, and the paper discharge means provided inside the casing. A control unit that controls the operation of the friction pad, the friction pad has a friction part formed on the upper part thereof so that the conveyance direction of the recording paper is the longitudinal direction, and when feeding the recording paper, The recording paper that is in contact with the paper feed roller is conveyed into the housing while being in sliding contact with the friction portion, and the other recording paper is held in the paper feed tray by being in contact with the friction portion. The friction pad is formed between the upstream portion in the transport direction and the downstream portion in the transport direction, with a substantially central portion in the transport direction of the recording paper as a boundary. Constructed integrally using different rubber materials The portion of the recording paper on the downstream side in the conveyance direction is made of a rubber member having a hardness higher than that of the rubber member constituting the portion on the upstream side of the conveyance direction. Even if it exists, it is comprised so that it may feed appropriately in the said housing | casing one sheet at a time.

  According to a second aspect of the present invention, there is provided a housing, a paper feed tray that is provided in the housing and is loaded so that the recording paper is stood thereon, and a front end portion of the recording paper loaded in the paper feeding tray. A resin friction pad attached to the housing so as to abut, and the recording paper loaded in the paper feed tray is fed substantially horizontally into the housing while being in sliding contact with the friction pad. An image forming apparatus that forms an image while feeding and feeding the fed recording paper inside the housing, wherein the friction pad is located on the upstream side of the friction pad with respect to the conveyance direction of the recording paper. The part on the downstream side in the transport direction is configured so that the hardness of the friction pad is higher.

  According to a third aspect of the present invention, in the second aspect of the present invention, the friction pad is different from the upstream portion in the transport direction and the downstream portion in the transport direction with a substantially central portion in the transport direction of the recording paper as a boundary. The recording paper is integrally molded using a resin having hardness, and the downstream portion of the recording paper in the transport direction is made of a resin having a higher hardness than the resin constituting the upstream portion in the transport direction.

  According to the first aspect of the present invention, the friction pad is so-called two-color molded using two rubber members made of different materials, and the friction pad is located on the downstream side in the conveyance direction from the upstream side in the conveyance direction of the recording paper. Since the friction part has higher hardness, the resistance force acting on the recording paper when the leading edge of the recording paper and the downstream portion in the conveying direction of the friction pad are in contact with each other in the conveying direction of the leading edge of the recording paper and the friction pad. This is smaller than the resistance force acting on the recording paper when the upstream portion is in sliding contact. Therefore, when the uppermost recording paper comes into sliding contact with the downstream portion of the friction pad in the conveyance direction during paper feeding, the paper feeding direction compared to other recording paper loaded in the paper feeding tray It becomes easy to be transported toward. Therefore, for example, various recording sheets such as a recording sheet having a large thickness or a so-called strong recording sheet can be appropriately fed into the housing one by one. Further, since the friction pad can be integrally formed by two-color molding, the friction pad can be easily manufactured at low cost, and the manufacturing cost of the image forming apparatus can be kept low.

  According to the second aspect of the invention, the friction pad is configured such that the hardness of the friction portion is higher in the downstream portion in the transport direction than in the upstream portion in the transport direction of the recording paper. When the uppermost recording paper comes into sliding contact with the downstream portion of the friction pad in the transport direction, it is transported in the paper feed direction as compared with other recording paper loaded in the paper feed tray. It becomes easy. Therefore, various recording sheets can be properly fed into the housing one by one.

  According to the invention of claim 3, since the friction pad is integrally molded using different resins for the upstream portion in the conveyance direction of the recording paper and the downstream portion in the conveyance direction, the friction pad can be easily reduced. It can be manufactured at low cost, and the manufacturing cost of the image forming apparatus can be kept low.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 and 2 show a schematic configuration of a photo printer (hereinafter referred to as an image forming apparatus 1) which is an example of an image forming apparatus according to the present embodiment.

  The image forming apparatus 1 includes a paper feed tray 2 loaded and held with a recording paper P, a transport mechanism 3 that transports the recording paper P held in the paper feed tray 2, and a recording paper transported by the transport mechanism 3. An image forming unit (image forming unit) 4 that forms an image on P, a paper discharge tray 5 that receives the recording paper P on which an image has been formed and discharged by the image forming unit 4, a transport mechanism 3, and an image forming unit 4 are accommodated. And a control unit 50 configured to control the transport mechanism 3 and the image forming unit 4. As shown in FIG. 2, the paper feed tray 2 is erected on the back surface of the housing 6 so that the loading surface of the recording paper P is inclined toward the housing 6. Inside the housing 6, a substantially horizontal sheet passing surface 6 a serving as a conveyance path for the recording paper P is provided. The recording paper P is loaded so as to lean against the paper feed tray 2 with its leading end in contact with the paper passing surface 6 a of the housing 6.

  The transport mechanism 3 includes a paper feeding roller 31 for feeding the recording paper P held in the paper feeding tray 2 into the housing 6, and the recording paper P fed by the paper feeding roller 31 as an image forming unit. A first conveying mechanism (conveying means) 3 a that conveys the image to the image forming position 4, and a second conveying mechanism (discharging means) 3 b that conveys the recording paper on which the image is formed by the image forming unit 4 to the paper discharge tray 5. And a feed motor 30 for driving the paper feed roller 31, the first transport mechanism 3a, and the second transport mechanism 3b. The paper feed roller 31 feeds the recording paper P toward the housing 6 by rotating in contact with the uppermost one of the recording paper P loaded in the paper feed tray 2. When the recording paper P is fed into the housing 6 from the state of leaning on the paper feed tray 2, the recording paper P assumes a substantially horizontal posture along the paper passing surface 6a. Then, inside the housing 6, the first transport mechanism 3 a and the second transport mechanism 3 b are transported substantially horizontally in the transport direction indicated by the arrow F in FIG.

  The first transport mechanism 3 a is provided on the upstream side of the print head 43 of the image forming unit 4. The first transport mechanism 3 a transports the recording paper P sent out by the paper feed roller 31 to the print head 43, and the recording paper P. It is constituted by a pressing roller 33 or the like that presses the conveying roller 32. The second transport mechanism 3b includes a paper discharge roller 38 that transports the recording paper P on which an image is formed to the paper discharge tray 5, a star wheel 39 that presses the recording paper P against the paper discharge roller 38, and the like. Yes.

  The image forming unit 4 is configured to form an image on the recording paper P by an inkjet method, and supports the ink cartridge 40 filled with ink and the conveyance direction F of the recording paper P while supporting the ink cartridge 40. A carrier 41 that reciprocates in a substantially orthogonal main scanning direction, a carrier drive motor 42 that drives the carrier 41, and the like. A print head 43 that ejects ink onto the recording paper P is provided on the lower surface of the ink cartridge 40. The carrier 41 is supported by a shaft 44 disposed substantially parallel to the main scanning direction so as to be reciprocally movable, and is driven by the carrier drive motor 42 to move. The output of the carrier drive motor 42 is transmitted to the carrier 41 via a belt or the like. Under the control of the control unit 50, ink is ejected from the print head 43 in synchronization with the drive of the feed motor 30 and the carrier drive motor 42, and an image is formed on the recording paper P.

  As shown in FIG. 1, a handle 7 that is gripped when carrying the image forming apparatus 1 is rotatably provided on the upper surface of the housing 6. On the front surface of the housing 6, for example, a card connector 53a to which a detachable memory is attached, and a USB connector 53b to which other electronic devices such as a digital still camera are connected directly or via a cable are arranged. ing. Further, on the top surface of the housing 6, a liquid crystal panel 54 that displays images to be printed and operation states, operation buttons 55 used for selecting an image to be printed and setting the number of prints, and turning on / off the apparatus. Or an auxiliary button 59 or the like used together with the operation button 55 or the like for performing various settings. Inside the housing 6, a card connector 53 a, a USB connector 53 b, a liquid crystal panel 54, and the like are connected to the upper part of the housing 6. A switch board 52 on which a plurality of tact switches and the like are mounted so as to correspond to the buttons 55 and the auxiliary buttons 59 is arranged substantially horizontally, and the control unit 50 is configured by the control board 51 and the switch board 52. Yes.

  FIG. 3 shows the sheet passing surface 6 a of the sheet feeding tray 2 and the housing 6. An arrow F in the figure indicates the feeding / conveying direction of the recording paper P. In the image forming apparatus 1, as shown in the figure, a separation mechanism 20 is disposed at a substantially central portion in the vicinity of a portion of the sheet passing surface 6 a where the sheet feeding tray 2 is attached. The separation mechanism 20 is disposed so that the leading end of the recording paper P loaded in the paper feed tray 2 is in contact with the upper part of the separation mechanism 20, and the recording mechanism loaded in the paper feed tray 2 and fed by the paper feed roller 31. The paper P is configured to be separated from other recording papers P by being brought into sliding contact with the separation mechanism 20 and fed one by one from the paper feed tray 2 into the housing 6.

  FIG. 4 shows the separation mechanism 20. The separation mechanism 20 includes a friction pad 21 made of a rubber material and a cover 25 that is a resin member formed so as to cover the upper portion of the friction pad 21. The separation mechanism 20 is disposed in the housing 6 so that the conveyance direction F of the recording paper P is the longitudinal direction.

  As shown in FIG. 4, the friction pad 21 is formed such that a cross section perpendicular to the conveyance direction F of the recording paper P has a mountain shape that protrudes upward. On the upper part of the friction pad 21, a friction part 21a formed in the longitudinal direction along the conveying direction F and having a sawtooth shape, for example, is provided on the upper part. A hole 25a is formed in the upper surface of the cover 25 so that the friction part 21a of the friction pad 21 passes therethrough. Further, on both sides of the cover 25, engaging portions 25b are formed so as to engage with mounting portions (not shown) provided at positions where the separation mechanism 20 on the sheet passing surface 6a is disposed. The friction pad 21 is attached to the inside of the cover 25 so that the cover 25 is covered from the upper surface thereof, and the friction portion 21a is exposed to the upper surface of the cover 25 through the hole 25a. The separation mechanism 20 configured by combining the friction pad 21 and the cover 25 is fixed on the sheet passing surface 6a when the engaging portion 25b is engaged with the attachment portion. The recording paper P loaded in the paper feed tray 2 is in a state where the leading end thereof is in contact with the friction portion 21 a exposed on the upper surface of the separation mechanism 20. That is, the recording paper P is prevented from slipping from the paper supply tray 2 toward the inside of the housing 6 due to the static frictional force generated between the friction portion 21a and the leading end of each recording paper P. 2 is held.

  Here, in the present embodiment, the friction pad 21 is located on the upstream side in the conveyance direction of the recording paper P (hereinafter referred to as the substantially central portion in the longitudinal direction of the friction pad 21, that is, in the conveyance direction F of the recording paper P). , 21s and a downstream portion (hereinafter referred to as a downstream portion) 21h in the transport direction are made of rubber members made of different materials. The upstream portion 21s is formed of a rubber member that is relatively soft, that is, low in hardness, and is configured to be easily deformed when the friction portion 21a is pushed downward from above. On the other hand, the downstream portion 21h is made of a rubber member having a hardness higher than that of the upstream portion 21s, and is configured to be more difficult to deform than the upstream portion 21s when the friction portion 21a is pushed downward. The friction pad 21 is integrally configured by so-called two-color molding using two types of rubber members having different materials.

  Next, the recording paper P feeding operation will be described with reference to FIG. FIG. 5 shows the vicinity of the leading end of the recording paper P loaded in the paper feed tray 2. In the figure, the separation mechanism 20 shows only the friction pad 21 for explanation. When the recording paper P is loaded in the paper feed tray 2, the leading end of the recording paper P is held in contact with the friction portion 21 a of the upstream portion 21 s of the friction pad 21. When the paper feed roller 31 rotates, among the recording papers P loaded in the paper feed tray 2, the uppermost recording paper P0 in contact with the paper feed roller 31 is the paper feed tray 2 as shown in the figure. Is biased toward the friction pad 21. As the paper feed roller 31 rotates, the vicinity of the front end portion of the recording paper P0 is bent, and is slidably contacted with the friction portion 21a of the friction pad 21, so that the recording paper P0 slides in the transport direction F. It will be done. At this time, when the recording paper P0 is urged by the paper feed roller 31, the recording paper P1 below the recording paper P0 and the recording paper P2 below the recording paper P0 are respectively between the recording paper P0 and the recording paper P1. It is biased toward the friction pad 21 by the frictional force and the frictional force between the recording paper P1 and the recording paper P2. Here, when the leading end of the recording paper P0 comes into sliding contact with the friction portion 21a of the downstream portion 21h, the recording paper P0 moves in the transport direction F that acts on the recording paper P when the leading end of the recording paper P0 and the friction pad 21 come into sliding contact. Is less than the resistance force acting on the recording paper P0 when the recording paper P0 comes into sliding contact with the upstream portion 21s. That is, at this time, the resistance force to the slide in the transport direction F acting on the recording paper P0 is smaller than the resistance force acting on the other recording paper P such as the recording paper P1, P2, and the recording paper P0 is the other recording paper. Since it is easier to slide in the transport direction F than P, the recording paper P0 is separated from the other recording paper P and fed substantially horizontally into the housing 6, and the other recording paper P is fed to the paper feed tray 2. Is maintained while being maintained.

  As described above, in the present embodiment, the friction pad 21 is made of a rubber material having a higher hardness in the downstream portion 21h than in the upstream portion 21s. Various recording papers P such as a strong recording paper can be properly fed into the housing 6 one by one. Further, since the friction pad 21 can be integrally formed by so-called two-color molding using two rubber members, the friction pad 21 can be easily manufactured at low cost, and the manufacturing cost of the image forming apparatus 1 can be reduced. It becomes possible to keep.

  In addition, this invention is not limited to the structure of the said embodiment, A various deformation | transformation is possible suitably in the range which does not change the meaning of invention. For example, the friction pad may be configured such that the hardness gradually increases along the recording paper conveyance direction F, and the hardness of the portion downstream in the conveyance direction is higher than the region upstream of the conveyance direction. It suffices if it is configured to be high. Further, the image forming unit is not limited to the one that forms an image by an ink jet method as described above, and may be configured to form an image by an electrophotographic method, for example.

1 is a perspective view showing an image forming apparatus according to an embodiment of the present invention. The side view which shows the structure of the said apparatus. The perspective view which shows the site | part in which the paper feed tray of the said apparatus is provided. The perspective view which shows the separation mechanism of the said apparatus. FIG. 4 is a side sectional view showing a friction pad when recording paper is fed in the apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Paper feed tray 3a Conveyance mechanism (conveyance means)
3b Transport mechanism (paper discharge means)
4 Image forming unit (image forming means)
DESCRIPTION OF SYMBOLS 5 Paper discharge tray 6 Case 21 Friction pad 21a Friction part 31 Paper feed roller 50 Control part F Conveyance direction P, P0, P1, P2 Recording paper

Claims (3)

A housing,
A paper feed tray that is provided on the back side of the casing, and the recording paper is stowed and loaded in a state in which a leading end thereof is in contact with the casing;
A friction pad made of a rubber member attached to the housing and arranged to come into contact with the leading end of the recording paper loaded in the paper feed tray;
The recording paper is rotated in contact with the uppermost recording paper among the recording paper loaded in the paper feed tray, and the recording paper is fed substantially horizontally into the housing while being in sliding contact with the friction pad. A paper feed roller
Conveying means for conveying the recording paper fed by the paper feeding roller inside the housing;
Image forming means for forming an image on the recording paper being conveyed by the conveying means;
A paper discharge means for conveying the recording paper on which the image is formed by the image forming means to the outside of the apparatus;
A paper discharge tray for receiving the recording paper conveyed by the paper discharge means and discharged to the outside of the housing;
A control unit that is provided inside the housing and controls operations of the paper feeding unit, the image forming unit, and the paper discharging unit;
The friction pad has a friction part formed on the upper part so that the conveyance direction of the recording paper is the longitudinal direction, and when the recording paper is fed, the recording paper that contacts the paper feeding roller is Image formation configured to be conveyed inside the housing while being in sliding contact with the friction portion, and the other recording paper being held in the paper feed tray by being in contact with the friction portion. A device,
The friction pad is integrally formed using a rubber member made of a material different from each other at a site upstream in the transport direction and a site downstream in the transport direction, with a substantially central portion in the transport direction of the recording paper as a boundary. The part on the downstream side in the conveyance direction of the recording paper is composed of a rubber member having higher hardness than the rubber member constituting the part on the upstream side in the conveyance direction,
Accordingly, the image forming apparatus is configured so that even a recording sheet having a large sheet thickness is appropriately fed into the housing one by one. A housing,
A paper feed tray that is provided in the housing and is loaded so that the recording paper is leaned against it;
A resin friction pad attached to the housing so that the leading end of the recording paper loaded in the paper feed tray abuts,
The recording paper loaded in the paper feed tray is fed substantially horizontally into the housing while being in sliding contact with the friction pad, and an image is formed while the fed recording paper is transported inside the housing. An image forming apparatus that
The friction pad is configured such that the hardness of the friction pad is higher at the downstream side of the friction pad than the upstream side of the recording paper in the transport direction. Forming equipment. The friction pad is integrally molded using resins having different hardnesses at a site upstream in the transport direction and a site downstream in the transport direction, with a substantially central portion in the transport direction of the recording paper as a boundary. 3. The image forming apparatus according to claim 2, wherein the downstream portion of the paper in the transport direction is made of a resin having a higher hardness than the resin constituting the upstream portion of the transport direction.

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