JP2011063334A - Image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve a simple mechanism for correctly holding a movable guide member in a reference position in a closed state of a cover member. <P>SOLUTION: This image forming device includes the movable guide member (80) having flexibility in the width direction of a passage (301) and movably supported in the vertical direction in a state of extending a shoe guide part (82) to the passage (301), two legs (83) for holding the movable guide member (80) in the reference position while being placed in a fixing part at the lower part of right-left end outside positions of the passage (301) in the movable guide member (80), a plurality of projections (84) arranged projecting upward in a position separated by a predetermined distance to the inside from the right-left ends of the passage (301) in the movable guide member (80), and a regulating part (91) arranged inside a cover (5) and in close vicinity from above to the plurality of projections (84) in the closed state of the cover (5) when the movable guide member (80) exists at the reference position. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus characterized by a movable guide holding mechanism that guides a sheet material supplied from an openable sheet tray to a predetermined path.

  In general, an electrophotographic image forming apparatus transfers a toner image and heat-fixes a sheet material such as paper or PET sheet along the predetermined path while conveying the sheet material. At that time, the sheet material being conveyed is guided along the predetermined path by the guide portion. Further, a movable guide member and a cover portion that is supported so as to be able to open and close an area where the movable guide member is disposed is often provided at a position where the change of the sheet material conveyance direction is abrupt. . Hereinafter, such a movable guide member is referred to as a movable guide member.

  When the sheet material is conveyed to a path extending in a vertical direction from a horizontally tilted state, for example, in a section from the paper feeding unit to the image transfer unit, the direction is changed by about 90 ° with a relatively steep curve. Is done. Even in the section from the fixing device that heats and fixes the toner image transferred to the sheet material while being conveyed upward to the paper discharge roller that discharges the sheet material in the lateral direction, the sheet material has a relatively steep curve. A turn of about 90 ° is performed. For this reason, the movable guide member is often arranged in a section from the paper feed section to the image transfer section and a section from the fixing device to the discharge section.

  The movable guide member is movable between a first position along which the sheet guide part for guiding the sheet material to a predetermined path is along the predetermined path and a second position where the sheet guide part is separated from the predetermined path. Supported by Hereinafter, the first position is referred to as a reference position, and the second position is referred to as a retracted position. When the movable guide member is moved to the retracted position, the path of the sheet material is released, so that the image forming apparatus can easily release the jammed sheet material.

  On the other hand, many image forming apparatuses include an openable and closable sheet tray on which a sheet material supplied to a carry-in unit that is an entrance of a sheet material conveyance path is placed. This openable sheet tray is generally called a manual feed tray. Such an image forming apparatus includes a cover portion that is supported so that the region where the carry-in portion is disposed can be opened and closed from the outside. The openable sheet tray is supported such that a portion of the closed cover portion communicating with the carry-in portion can be opened and closed from the outside, and the sheet material supplied to the carry-in portion in the opened state is placed Is done.

  The movable guide member is often provided to guide the sheet material supplied from the openable sheet tray in the subsequent stage of the carry-in portion. Such a movable guide member is formed with a sheet guide portion that guides the sheet material along a predetermined path that continues from the carry-in portion to the subsequent stage. Further, the movable guide member is supported so as to be movable in the vertical direction in a state where the sheet guide portion is stretched over the predetermined path.

  By the way, when a stiff sheet material such as thick paper is used, the position of the movable guide member is shifted from the reference position, and the sheet material is likely to be clogged. Further, the movable guide member for guiding the sheet material supplied from the openable sheet tray guides the sheet material in a state where the carry-in portion is released to the outside. Therefore, when the movable guide member that guides the sheet material supplied from the openable sheet tray is swung by the pressing force of the sheet material, the movable guide member continuously collides with a portion supporting the sheet material to generate a sound. Sound leaks from the carry-in part to the outside and becomes loud noise.

  Accordingly, it is important that the movable guide member is correctly held at the reference position when the cover portion is closed. For example, Patent Document 1 discloses an image forming apparatus including a biasing member that biases the movable guide member in a closing direction when the movable guide member that opens and closes in conjunction with opening and closing of the cover portion is opened. Yes.

JP 2006-251470 A

  However, the image forming apparatus disclosed in Patent Document 1 requires a mechanism for interlocking the movable guide member and the cover, which has the problem of increasing the number of assembling steps and costs.

  On the other hand, it is conceivable to provide a protrusion on the inner side of the cover portion for positioning the movable guide portion by contacting the movable guide member. The protrusion directly contacts the movable guide portion with the cover portion closed.

  However, in the configuration, there is a problem that the operation of closing the cover part is excessive, the projection part collides with the movable guide part having high rigidity, and the movable guide part or the projection part is damaged. Usually, the cover part is provided with a lock mechanism for holding the closed state and releasing the state, and before being held by the lock mechanism, the cover unit is temporarily placed in the main unit more than the holding position in the closed state. This is because it has a structure that enters inside.

  An object of the present invention is to provide an image forming apparatus including a simple mechanism for correctly holding a movable guide member at a reference position in a state where a cover portion is closed.

  In order to achieve the above object, an image forming apparatus according to the present invention includes the following components. The first component is a cover that is supported so as to be openable and closable from the outside in the region where the sheet material carrying-in portion is disposed. The second component is supported such that a portion of the closed cover portion communicating with the carry-in portion can be opened and closed from the outside, and the sheet material supplied to the carry-in portion is placed in an open state. An openable sheet tray. The third component is formed with a sheet guide part that guides the sheet material along a predetermined path that continues from the carry-in part to the subsequent stage, and has flexibility in a width direction of the predetermined path, It is a movable guide member that is supported so as to be movable in the vertical direction in a state in which the guide portion is stretched over the predetermined path. The fourth component is provided at a lower portion of the movable guide member at a position outside the left and right ends of the predetermined path, and is placed on a predetermined fixing portion so that the movable guide member is moved to the seat. The guide part is two legs that are held at a reference position along the predetermined path. The fifth component is a plurality of protrusions provided to protrude upward at positions spaced a predetermined distance inward from the left and right ends of the predetermined path in the movable guide member. A sixth component is provided inside the cover part, and is in a state in which the movable guide member is in the reference position and the cover part is closed, and the restriction is adjacent to or in contact with the plurality of protrusions from above. Part.

  According to the present invention, in a state where the cover portion is closed, the lift of the movable guide member is restricted by the plurality of protrusions and the restricting portion, and the simple guide mechanism that correctly holds the movable guide member at the reference position. Can be realized. Further, in the width direction of the predetermined path, the position of the leg portion and the position of the projection portion in the movable guide member are shifted. Furthermore, the movable guide member has flexibility in the width direction of the predetermined path. Therefore, even when the restriction portion collides with the plurality of protrusions when the cover portion is closed, the impact of the collision is absorbed by the deflection of the movable guide member. Therefore, damage to the restricting portion and the plurality of protrusions due to the collision is avoided.

1 is a cross-sectional view of an image forming apparatus 1 according to an embodiment of the present invention. 3 is a cross-sectional view illustrating a state in which an openable sheet tray is opened in the image forming apparatus 1. FIG. FIG. 4 is a cross-sectional view of the vicinity of a second paper feed roller in the image forming apparatus 1. 3 is a perspective view of a movable guide member in the image forming apparatus 1. FIG. FIG. 3 is a cross-sectional view illustrating a state where a cover portion is opened in the image forming apparatus 1.

  Embodiments of the present invention will be described below with reference to the accompanying drawings for understanding of the present invention. In addition, the following embodiment is an example which actualized this invention, Comprising: The thing of the character which limits the technical scope of this invention is not.

  First, an overall configuration of an image forming apparatus 1 according to an embodiment of the present disclosure will be described with reference to a cross-sectional view shown in FIG. The image forming apparatus 1 is an electrophotographic image forming apparatus that forms a toner image on a sheet material such as paper or a PET sheet, which is a medium to which an image is transferred. The image forming apparatus 1 is a double-sided printing type image forming apparatus capable of forming toner images on both front and back sides of a sheet material.

  As shown in FIG. 1, the image forming apparatus 1 includes a scanner unit 2, a paper feed cassette 3, a first paper feed roller 10, a registration roller 20, an image transfer unit 30, a fixing device 40, a paper discharge roller 60, a turnback. A driven roller 50 for turn, a drive roller for turn back 900, a paper discharge tray 4, a cover portion 5, an openable sheet tray 6, a second paper feed roller 70, a movable guide member 80, and the like. An image forming apparatus 1 shown in FIG. 1 is a so-called multi-function machine that functions as a printer and a copying machine, and also functions as a facsimile machine.

  The scanner unit 2 is an apparatus that reads an image from a document and generates image data. The paper feed cassette 3 is a container for storing a plurality of sheet materials. The first paper feed roller 10 is a roller for feeding sheet materials stored in the paper feed cassette 3 one by one to a predetermined transport path. The registration rollers 20 are a pair of rollers that hold the sheet material fed by the first paper feed roller 10 and feed the sheet material to the image transfer unit 30 at a predetermined timing.

  The image forming apparatus 1 also includes a second paper feed roller 70 in addition to the first paper feed roller 10. The second paper feed roller 70 is a device that carries a sheet material placed on an openable sheet tray 6 described later into the device from outside the device, and is an example of a carry-in unit. The sheet material supplied from the second paper feed roller 70 is also conveyed to the image transfer unit 30 through the registration roller 20. In other words, the sheet material conveyance paths corresponding to the first paper feed roller 10 and the second paper feed roller 70 are joined before the registration roller 20.

  The image transfer unit 30 is a device that transfers the toner image to the sheet material while further conveying the sheet material conveyed from the registration roller 20 to the fixing device 40 in the subsequent stage. The image transfer unit 30 includes a photosensitive drum as an image carrier and a plurality of devices arranged around the photosensitive drum. Around the photosensitive drum, a charging device, an exposure device, a developing device, a transfer device, a cleaning device, and the like are arranged.

  The fixing device 40 is a device that fuses the toner transferred to the sheet material to the sheet material while further conveying the sheet material conveyed from the image transfer unit 30 to the subsequent stage.

  The paper discharge roller 60 is a roller for discharging the sheet material conveyed from the fixing device 40 to the paper discharge tray 4. Further, the paper discharge roller 60 also functions as a turnback roller that reverses and conveys a sheet material on which an image is formed on one side for double-sided printing. The sheet material reversed and conveyed by the paper discharge roller 60 is conveyed downward by the turnback drive roller 900 and the turnback driven roller 50, passes through the movable guide member 80, and again enters the registration roller. 20 and the image transfer unit 30.

  Further, the image forming apparatus 1 includes a cover portion 5 that is supported so that its side surface can be opened and closed. More specifically, the cover portion 5 is rotatably supported by a support shaft (not shown) at the lower portion thereof. The cover unit 5 is turned to the open side 201 by being turned in the direction 201 from the closed state where the cover unit 5 is held upright to the outside. The cover part is supported so that it can be opened and closed from the outside, including substantially the entire side surface including the area where the second paper feed roller 70, which is a sheet material carrying-in part, is disposed. Further, the cover unit 5 includes a lock mechanism that holds the main body of the image forming apparatus 1 in a closed state and releases the closed state. The locking mechanism is not shown.

  The image forming apparatus 1 further includes an openable and closable sheet tray 6 that is supported so that the lower portion of the cover 5 can be opened and closed. FIG. 2 is a cross-sectional view showing a state in which the openable sheet tray 6 is opened. The openable sheet tray 6 is supported so that a portion of the closed cover portion 5 communicating with the second paper feed roller 70 can be opened and closed from the outside. More specifically, the openable sheet tray 6 is rotatably supported by a support shaft (not shown) at the lower part thereof. Therefore, the openable sheet tray 6 can be rotated in the direction 203 from the upright state along the side surface of the apparatus main body to the outside, and in the direction 204 from the open state tilted laterally toward the apparatus main body.

  The openable sheet tray 6 is placed with a sheet material supplied to the second paper feed roller 70 in an opened state. The openable and closable sheet tray 6 shown in FIG. 2 is configured to be extendable and retractable by a drawer structure including a plurality of trays. The openable sheet tray 6 is accommodated in the cover portion 5 in a state where the openable sheet tray 6 is contracted the smallest.

  The sheet material placed on the openable sheet tray 6 is sent out one by one by the second paper feed roller 70 to the conveyance path toward the registration roller 20 and the image transfer unit 30. A movable guide member 80 that guides the sheet material to a predetermined path toward the registration roller 20 is provided at the subsequent stage of the second paper feed roller 70.

  When functioning as a copying machine, the image forming apparatus 1 operates as follows under the control of a controller (not shown). First, the scanner unit 2 reads an image from a document, and the first paper supply roller 10 or the second paper supply roller 70 and the registration roller 20 convey a sheet material to the image transfer unit 30. Next, the image transfer unit 30 transfers the toner image corresponding to the image data obtained by the scanner unit 2 to one surface of the sheet material. Next, the fixing device 40 heats and fixes the toner on the sheet material to the sheet material. Finally, the paper discharge roller 60 discharges the sheet material on which the image is formed to the paper discharge tray 4.

  When the image forming apparatus 1 functions as a printer, a communication interface (not shown) and a control unit execute a process of receiving image data from an external computer instead of the image reading process by the scanner unit 2. . Similarly, when the image forming apparatus 1 performs a reception process as a facsimile apparatus, a modem and a control unit (not shown) receive an incoming call from another facsimile apparatus through a telephone line instead of the image reading process by the scanner unit 2. Processing and image data reception processing are executed.

  Next, the peripheral portion of the second paper feed roller 70 will be described in detail with reference to the cross-sectional views shown in FIGS. 3 and 5 and the perspective view shown in FIG. In FIG. 3, descriptions of the cover portion 5 and the openable sheet tray 6 are omitted.

  The second paper feed roller 70 is disposed at the entrance of the sheet material placed on the openable sheet tray 6 into the apparatus. A friction pad 110 is elastically biased to the second paper feed roller 70 from below. The sheet material placed on the openable sheet tray 6 is carried into the apparatus one by one by the action of the rotating second sheet feeding roller 70 and the friction pad 110.

  In the image forming apparatus 1, a section from the second paper feed roller 70 that carries the sheet material laterally into the apparatus to the registration roller 20 that conveys the sheet material upward and the image transfer unit 30 is a sheet. This is a section where the material is turned by about 90 ° with a relatively steep curve. Therefore, the section is a section in which jamming (clogging) of the sheet material is likely to occur. Therefore, the image forming apparatus 1 includes a movable guide member 80 disposed in a section from the second paper feed roller 70 to the registration roller 20.

  The sheet material supplied into the apparatus by the second paper feed roller 70 enters between the lower sheet guide portion 120 and the upper sheet guide portion 82 that are arranged at the subsequent stage of the second paper feed roller 70. The lower sheet guide portion 120 and the upper sheet guide portion 82 are portions that guide the sheet material along a first conveyance path 301 that is a predetermined path that continues from the second paper feed roller 70 to the subsequent stage. The upper sheet guide portion 82 is formed on a part of the movable guide member 80.

  FIG. 4 is a perspective view of the movable guide member 80. The movable guide member 80 is an integrally molded resin member. For example, the movable guide member 80 is a member made of a resin such as ABS, polycarbonate, or polystyrene. The movable guide member 80 includes a supported portion 81 serving as a rotation center, the upper sheet guide portion 82, and two leg portions 83. Further, two protrusions 84, a plurality of ribs 85, and a roller cover portion 86 are formed on the surface of the upper sheet guide portion 82 opposite to the surface along the first conveyance path 301. Has been.

  The movable guide member 80 is arranged such that its longitudinal direction is along the width direction of the first transport path 301, that is, the width direction of the sheet material to be transported. Further, the movable guide member 80 is rotatably supported by the supported portions 81 at both ends in the longitudinal direction being supported by bearing portions on the main device side. As a result, the movable guide member 80 is supported so as to be rotatable in the vertical direction in a state where the upper sheet guide portion 82 is stretched over the first conveyance path 301.

  The plurality of ribs 85 are arranged in the longitudinal direction of the upper sheet guide portion 82 with the conveying direction of the sheet material as the longitudinal direction. The plurality of ribs 85 function as reinforcing portions that reinforce the movable guide member 80 so as not to bend in the sheet material conveyance direction. Therefore, the movable guide member 80, which is an integrally molded product of resin, has flexibility in the width direction of the first conveyance path 301, that is, in the longitudinal direction thereof, but in the conveyance direction of the sheet material. Almost does not flex.

  The plurality of ribs 85 also function as guide portions that guide the sheet material whose conveyance direction is reversed by the paper discharge roller 60 shown in FIG. 1 to the registration roller 20 and the image transfer unit 30. Therefore, the plurality of ribs 85 are formed along the second conveyance path 302 that is the conveyance path of the sheet material in which the tops of the ribs 85 are reversed in direction. The cover portion 5 is provided with cover portion side sheet guide portions 92 and 93 that guide the sheet material along the second conveyance path path 302 together with the ribs 85 when the cover portion 5 is closed. Yes.

  The roller cover portion 86 provided on the movable guide member 80 is a portion that covers a part of the second paper feed roller 70. The roller cover portion 86 prevents the sheet material conveyed along the second conveyance path 302 from being caught by the second paper feed roller 70 by mistake.

  The two leg portions 83 are provided at the lower part of the movable guide member 80 at positions outside the left and right ends of the first transport path 301. More specifically, the two leg portions 83 are provided at both end portions in the longitudinal direction of the upper sheet guide portion 82. Then, by placing the two leg portions 83 on a predetermined fixed portion, the movable guide member 80 is held at a reference position where the upper sheet guide portion 82 is along the first conveyance path 301. The FIG. 3 shows a state in which the movable guide member 80 is held at the reference position. For example, the two leg portions 83 are placed on the left and right ends of the lower sheet guide 120 fixed along the first conveyance path 301.

  The movable guide member 80 is held at the reference position by its own weight, and when the portion on the second paper feed roller 70 side is lifted, the movable guide member 80 rotates upward with the supported portion 81 as a rotation center. Accordingly, the movable guide member 80 moves to a retracted position where the upper sheet guide portion 82 is separated from the first conveyance path 301. FIG. 5 shows a state where the cover portion 5 is opened and the movable guide member 80 is in the retracted position. In FIG. 5, a part of the cover 5 and the openable sheet tray 6 is not shown. If the movable guide member 80 is moved to the retracted position, the lower side of the first conveyance path 301 is released, so that the image forming apparatus 1 can easily release the jammed sheet material.

  By the way, when the movable guide member 80 for guiding the sheet material supplied from the openable sheet tray 6 is swung by the pressing force of the sheet material, the movable guide member 80 continuously collides with a fixed portion that supports the material to generate a sound. However, the sound leaks to the outside from the carry-in entrance where the second paper feed roller 70 is disposed, resulting in a loud noise. Therefore, it is important that the movable guide member 80 is correctly held at the reference position when the cover 5 is closed.

  In the image forming apparatus 1, when the cover 5 is closed, the two protrusions 84 provided on the movable guide member 80 and the restricting portion 91 provided on the inner side of the cover 5 Limit the floating of the movable guide member.

  The two protrusions 84 are provided to protrude upward at a position spaced a predetermined distance inward from the left and right ends of the first transport path 301 in the movable guide member 80. That is, the two protrusions 84 are provided on the inner side of the two leg portions 83 in the width direction of the first transport path 301. For example, when the interval between the two leg portions 83 is about 300 mm, the two projecting portions 84 are provided on the inner side by about 20 mm to 30 mm starting from each of the two leg portions 83.

  On the other hand, the restricting portion 91 is provided on the inner side of the cover portion 5, and when the movable guide member 80 is at the reference position and the cover portion 5 is closed, the restricting portion 91 is located above the two protruding portions. It is provided so that it may contact or adjoin from. Thereby, in a state where the cover portion 5 is closed, the restricting portion 91 restricts the upward movement range of the two protruding portions 84, and consequently restricts the upward movement of the movable guide member 80. .

  Therefore, in the image forming apparatus 1, even when a stiff sheet material passes through the first conveyance path 301, the movable guide member 80 is moved to the reference position by the action of the protrusion 84 and the restriction portion 91. Properly held nearby. As a result, the generation of noise due to the swing of the movable guide member 80 is prevented. Moreover, the holding mechanism for the movable guide member 80 is realized by a very simple structure.

  Further, in the width direction of the first transport path 301, the position of the leg portion 83 and the position of the projection portion 84 in the movable guide member 80 are shifted. Further, the movable guide member 80 has flexibility in the width direction of the first transport path 301. Therefore, even when the restricting portion 91 collides with the protruding portion 84 when the cover portion 5 is rotated and closed in the direction 202 toward the inside of the main body device, the impact of the collision is caused by the movable guide member. Absorbed by 80 deflections. Therefore, damage to the restricting portion 91 and the protruding portion 84 due to the collision is avoided.

  The image forming apparatus 1 described above has a structure in which the movable guide member 80 is rotatably supported around the supported portion 81 as a rotation center, but other structures may be employed. . For example, it is conceivable that the movable guide member 80 is supported so as to be linearly slidable between the reference position and the retracted position where the upper sheet guide portion 82 is separated from the first conveyance path 301. It is also conceivable that three or more projections 84 are provided inside the two leg portions 83 in the movable guide member 80.

  The present invention is applicable to an image forming apparatus.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Scanner part 3 Paper feed cassette 4 Paper discharge tray 5 Cover part 6 Retractable sheet tray 10 First paper feed roller 20 Registration roller 30 Image transfer unit 30 Transfer unit 40 Fixing device 50 Turnback driven roller 60 Ejection Paper roller 70 Second paper feed roller 80 Movable guide member 81 Supported portion 82 Upper sheet guide portion 83 Leg portion 84 Projection portion 85 Rib 86 Roller cover portion 91 Restriction portion 92, 93 Cover portion side sheet guide portion 110 Friction pad 120 Below Side sheet guide unit 301 First transport path 302 Second transport path 900 Turnback drive roller

Claims (4)

A cover portion that is supported so as to be able to be opened and closed from the outside in an area where the sheet material carry-in portion is arranged, and a state where the closed portion of the cover portion that communicates with the carry-in portion is supported from the outside so that it can be opened and closed. And an openable sheet tray on which the sheet material supplied to the carry-in unit is placed,
A sheet guide portion that guides the sheet material along a predetermined path that continues from the carry-in section to the subsequent stage is formed, has flexibility in a width direction of the predetermined path, and the sheet guide section is the predetermined path. A movable guide member supported so as to be movable in the vertical direction in a state of being stretched over
The movable guide member is provided at a lower portion of a position outside the left and right ends of the predetermined path, and is placed on a predetermined fixed portion, whereby the movable guide member is used as the sheet guide section. Two legs to hold in a reference position along
A plurality of protrusions provided to protrude upward at positions spaced a predetermined distance inward from the left and right ends of the predetermined path in the movable guide member;
A regulating portion provided inside the cover portion, and in a state where the movable guide member is at the reference position and the cover portion is closed;
An image forming apparatus comprising: A cover portion that is supported so as to be able to be opened and closed from the outside in an area where the sheet material carry-in portion is arranged, and a state where the closed portion of the cover portion that communicates with the carry-in portion is supported from the outside so that it can be opened and closed. And an openable sheet tray on which the sheet material supplied to the carry-in unit is placed,
A sheet guide portion that guides the sheet material along a predetermined path that continues from the carry-in section to the subsequent stage is formed, has flexibility in a width direction of the predetermined path, and the sheet guide section is the predetermined path. A movable guide member supported so as to be movable in the vertical direction in a state of being stretched over
The movable guide member is provided at a lower portion of a position outside the left and right ends of the predetermined path, and is placed on a predetermined fixed portion, whereby the movable guide member is used as the sheet guide section. Two legs to hold in a reference position along
A plurality of protrusions provided to protrude upward at positions spaced a predetermined distance inward from the left and right ends of the predetermined path in the movable guide member;
A regulating portion provided on the inner side of the cover portion, and in contact with the plurality of protrusions from above in a state where the movable guide member is at the reference position and the cover portion is closed;
An image forming apparatus comprising: A plurality of ribs whose longitudinal direction is the conveying direction of the sheet material are formed in the sheet guide portion.
The image forming apparatus according to claim 1. The movable guide member is an integrally molded resin member.
The image forming apparatus according to claim 3.

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