JP5328692B2 - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming device having a tray capable of keeping the projecting position of an extension plate even by unintended contact of a user, while preventing damage of the tray. <P>SOLUTION: This image forming device includes a casing and the tray rotatably installed between a first position of projecting from the casing and a second position in close vicinity to the casing, and is characterized in that the tray includes a baseplate having a first base end part for forming a first rotary part, a placing base having a second base end part for forming a second rotary part and the extension plate movable along the baseplate, and the baseplate includes a stopper for hindering the movement of the extension plate of turning to a tip part and holding the extension plate in the projecting position of projecting from the tip part of the baseplate, and the extension plate held in the projecting position exists in a separate position separated from the baseplate, and when the tray is turned to the second position from the first position, the tip part of the placing base adds force of turning to the baseplate to the extension plate, and releases holding of the extension plate by the stopper. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an image forming apparatus including a tray for supplying sheets from outside a casing.

  In many cases, an image forming apparatus such as a copier, a printer, a facsimile machine, or a multifunction machine having these functions includes a tray that supports sheets fed into the casing from the outside of the casing of the image forming apparatus. The tray can provide a user with simple sheet placement compared to a cassette disposed in the housing.

  In many cases, the tray is rotatably attached to the housing of the image forming apparatus. While the tray is not used, the tray is disposed at a position along the outer surface of the housing. When the tray is used, it is disposed at a position protruding from the housing. Such a rotating tray contributes to space saving of the image forming apparatus when not in use.

  A tray included in some image forming apparatuses includes an extension plate. The extension plate is nested in the tray and allows the tray to expand and contract (see, for example, Patent Document 1). The telescopic tray has a structure in which the extension plate is pulled out from the tray main body as necessary. Therefore, when not in use, the amount of protrusion of the tray from the housing of the image forming apparatus can be made relatively small. . In addition, since the size of the tray when disposed at a position along the outer surface of the housing is reduced, the extendable tray contributes to downsizing of the entire image forming apparatus.

JP 2003-312904 A

  As described above, the extendable tray contributes to space saving and downsizing of the image forming apparatus, but has some problems. For example, when the extended tray is rotated to a position along the casing of the image forming apparatus due to an erroneous operation by the user, the extension plate of the tray collides with the casing of the image forming apparatus, and the tray and / or Or the housing may be damaged.

  In order to avoid damage to the tray and / or the housing, the tray is automatically shortened by its own weight when the tray is rotated to a position along the housing of the image forming apparatus. It is also conceivable. According to such a design, damage to the tray and / or the housing is suppressed, but when the user unintentionally contacts the extension plate, the extension plate is accommodated in the tray body. . As a result, the support on the sheet on the tray becomes insufficient, causing the sheet to fall from the tray and / or the conveyance failure of the sheet within the housing of the image forming apparatus.

  The present invention has been made to solve the above-described problem, and prevents the extension plate from protruding even by contact unintended by the user while suppressing damage to the tray and / or the casing due to the user's erroneous operation. An object of the present invention is to provide an image forming apparatus including a tray capable of maintaining a position.

An image forming apparatus according to an aspect of the present invention mounts a housing that houses an image forming unit that forms an image on a sheet, and the sheet that protrudes from the housing and is supplied to the image forming unit. A tray attached to the housing so as to be rotatable between a first position and a second position closer to the housing than the first position, and the tray is rotatable relative to the housing. A base plate having a first base end portion formed with a first rotating portion connected to the first plate, and a first plate that is rotatably connected to the housing while the sheet is placed at the second position. A mounting table having a second base end portion formed with two rotating parts, and an extension plate movable along the base plate, wherein the base plate is disposed at a distal end portion of the base plate. The extension plate is prevented from moving toward the projecting position where the extension plate projects from the tip of the base plate. The extension plate, which includes a stopper to be held and is held at the protruding position, is in a separated position separated from the base plate, and when the tray is rotated from the first position to the second position, tip of the mounting table is a force toward the base plate to the extension plate, you and cancels the holding of the extension plate by the stopper.

  According to the above configuration, the sheet placed on the tray at the first position protruding from the casing is subjected to an image forming process by the image forming unit accommodated in the casing. The tray is rotated to a second position close to the housing of the image forming apparatus. As a result, space saving of the image forming apparatus while the tray is not used is achieved. The tray includes a base plate that is rotatably connected to the housing via the first rotating portion, and a mounting table that is connected to the housing via the second rotating portion. When the tray is in the second position, the sheet is placed on the placing table. The base plate rotates about the first rotation unit, and the mounting table rotates about the second rotation unit. As a result, the base plate and the mounting table rotate while drawing different rotation trajectories. The extension plate is movable along the base plate. The movement of the extension plate toward the tip of the base plate is hindered by the stopper of the base plate. The stopper holds the extension plate at the protruding position protruding from the tip of the base plate. Therefore, when the user unintentionally contacts the extension plate, the stopper plays a role of holding the extension plate in the protruding position. In the protruding position, the extension plate is separated from the base plate. When the tray is rotated from the first position to the second position, as described above, the base plate and the mounting plate rotate while drawing different rotation trajectories, so that the front end of the mounting table is placed on the base plate. The heading force will be applied to the extension plate. As a result, the extension plate is returned to a position close to the base plate, and the holding of the extension plate by the stopper is released. Thus, the extension plate moves toward the base end of the base plate and / or the mounting plate. Therefore, even if the user rotates the tray to the second position with the extension plate in the protruding position due to an erroneous operation, the extension plate does not collide with the casing, and the tray and / or casing is prevented from being damaged. Will be.

In the above-described configuration, the stopper includes a first clamping part and a second clamping part disposed adjacent to the first clamping part, and the extension plate has the first clamping part at the protruding position. parts and while the elastically deforming at least one of said second clamping portion, it is not preferable with a fitting piece which is fitted between the said second clamping portion and the first pinching portion.

  According to the above configuration, at least one of the first sandwiching portion and the second sandwiching portion is elastically deformed and sandwiches the insertion piece of the extension plate, so that the extension plate is firmly held at the protruding position. . Therefore, when the user unintentionally touches the extension plate, the stopper preferably plays a role of holding the extension plate in the protruding position.

In the above configuration, the second holding portion is preferably formed to be inclined so as to guide the extension plate moving toward the projecting position from a proximity position close to the base plate to the separation position. better not.

  According to the said structure, the extension board which moves toward a protrusion position will be suitably guided by the 2nd clamping part from the proximity position close | similar to a base plate to the separation | spacing position spaced apart from the base part. .

In the above configuration, the base plate includes a side wall projecting from a main surface facing the extension plate, and a slit is formed on the side wall along the moving direction of the extension plate. to include a boss to be inserted, when said tray toward said second position from the first position is moved, the boss is not preferable is movable along said slit.

  According to the said structure, a base plate and a mounting base are connected by inserting the boss | hub of a mounting base in the slit formed in the side wall of the base plate which protrudes from the surrounding surface facing an extension board. When the tray moves from the first position toward the second position, a slit along the moving direction of the extension plate is formed, so that the rotation trajectory of the mounting table with respect to the base plate becomes constant. Therefore, the mounting table can preferably release the holding of the extension plate by the stopper.

In the above structure, the base end portion of the extension plate lies in the projecting position, have preferred to be disposed at a position close to the distal end portion of the mounting table.

  According to the above configuration, since the force toward the base is applied to the base end of the extension plate close to the stopper, the mounting table can be held by the stopper without being affected by the deformation of the extension plate. Can be released.

In the above configuration, the front end portion of the mounting table includes a front end edge extending in the width direction of the sheet, and a pressing piece projecting toward the front end portion of the base plate from the front end edge, pressing piece, it is not preferable to apply the force toward the base plate to said proximal end of said extension plate lies in the projecting position.

  According to the said structure, since the press piece which protrudes from the front-end edge which forms the front-end | tip part of a mounting base is used, it becomes possible to apply the force which goes to a base plate intensively from a press piece to an extension board. Therefore, the mounting table can preferably release the holding of the extension plate by the stopper.

In the above configuration, an edge portion of the pressing piece is formed so as to be able to contact the base end portion of the extension plate existing at the protruding position, and the base end portion of the extension plate with respect to a normal line of the main surface When the tray is rotated from the first position toward the second position, the inclined edge is inclined toward the first base end portion from the contact point toward the base plate. The boss moves toward the distal end portion of the base plate, and the inclined edge contacts the base end portion of the extension plate existing at the protruding position, and extends the force toward the base plate. It has preferably be added to the base end portion of the plate.

  According to the above configuration, the edge of the pressing piece includes the inclined edge. The inclined edge is formed so as to be in contact with the base end portion of the extension plate existing at the protruding position. Further, the inclined edge is inclined from the contact point with the base end portion of the extension plate to the base plate toward the first base end portion with respect to the normal line of the main surface. When the tray is rotated from the first position toward the second position, the boss moves toward the tip of the base plate. As a result, the inclined edge comes into contact with the base end portion of the extension plate existing at the protruding position. As described above, the inclined edge of the pressing piece is inclined in the direction of the first base end portion from the contact point with the base end portion of the extension plate toward the base plate with respect to the normal line of the main surface. Thus, a force toward the base plate is suitably applied to the base end portion of the extension plate.

In the above structure, the pressing piece, it is not preferable to be arranged at a position close to the stopper.

  According to the above configuration, since the force toward the base plate can be applied intensively to the extension plate by the pressing piece close to the stopper, the mounting table is not affected by the bending deformation of the extension plate. The holding of the extension plate by can be released.

In the above configuration, the side wall includes an accommodation wall that forms a space for accommodating the insertion piece in cooperation with the main surface, and at least a part of the accommodation wall forms the first clamping portion, with two clamping portions extending toward the first clamping portion from said main surface, have preferably be pressed elastically deformed by the fitting pieces of the extension plate is in said projecting position.

  According to the said structure, since an insertion piece is accommodated in the space formed with an accommodation wall and a main surface, the movement range of an extension plate will be defined by the space between an accommodation wall and a main surface. The second holding part extending from the main surface toward the first holding part is pressed and elastically deformed by the fitting piece of the extension plate at the protruding position. Thus, the first holding part and the second holding part hold the fitting piece firmly. Therefore, when the user unintentionally touches the extension plate, the stopper preferably plays a role of holding the extension plate in the protruding position.

In the above configuration, the base portion guides the extension plate to the separation position while being in contact with the distal end portion of the extension plate that moves toward the projection position, and separates the extension plate at the projection position from the separation position. it preferred to include a guide piece for supporting at position.

  According to the above configuration, the extension plate is suitably supported at the separated position by the guide piece. Therefore, the extension plate can support the sheet suitably together with the mounting table.

In the above structure, the tray resides in the first position, it is not preferable that inclined downward toward the housing.

  According to the above configuration, when the user releases the holding of the extension plate by the stopper, the extension plate applies a force toward the base plate and / or the base end of the mounting table due to the weight of the extension plate. Therefore, the tray can be shortened efficiently.

In the above structure, the tray, it is not preferable to pivot upwardly to said second position from said first position.

  According to the above configuration, when the tray is rotated from the first position to the second position, the extension plate is directed toward the base plate and / or the base end of the mounting table by gravity applied to the extension plate, and the tray is preferably used. It will be shortened.

  According to the present invention, the protruding position of the extension plate can be maintained even by contact unintended by the user while suppressing damage to the tray and / or the casing due to the user's erroneous operation.

1 is an external perspective view schematically showing an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing an internal structure of the image forming apparatus shown in FIG. 1. FIG. 2 is a perspective view of a tray of the image forming apparatus shown in FIG. 1. FIG. 2 is a perspective view of a tray of the image forming apparatus shown in FIG. 1. It is a perspective view of the base plate of the tray shown by FIG.3 and FIG.4. It is a perspective view of the mounting base of the tray shown by FIG.3 and FIG.4. FIG. 5 is a perspective view of an extension plate of the tray shown in FIGS. 3 and 4. It is sectional drawing of the tray in a 1st position. It is an expanded sectional view which shows the structure of the storage space of the tray shown by FIG. It is sectional drawing of the tray in a 1st position. It is an expanded sectional view around the pressing piece of the tray shown in FIG. It is sectional drawing of the tray in the middle from the 1st position to the 2nd position. FIG. 13 is an enlarged cross-sectional view around the pressing piece of the tray shown in FIG. 12. It is sectional drawing of the tray in the middle from the 1st position to the 2nd position. It is an expanded sectional view which shows the structure of the storage space of the tray shown by FIG. It is sectional drawing of the tray in a 1st position. It is sectional drawing of the tray in a 1st position.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that terms used in the following description, such as “up”, “down”, “left”, “right” and the like, are merely for the purpose of clarifying the explanation and do not limit the present invention. Not what you want. In the following description, the term “sheet” means copy paper, coated paper, OHP sheet, cardboard, postcard, tracing paper, and other sheet materials that are subjected to image forming processing. The term “sheet width direction” means a direction orthogonal to the sheet conveyance direction. The term “sheet leading edge” means the edge of the sheet positioned at the leading edge in the sheet conveyance direction. The terms “upstream”, “downstream” and similar terms used in the following description mean “upstream”, “downstream” and similar concepts in the sheet conveyance direction.

  FIG. 1 is an external perspective view of an image forming apparatus according to an embodiment of the present invention. The image forming apparatus in FIG. 1 is a printer. However, in other embodiments, the image forming apparatus may be a copier, a facsimile, a multi-function machine having these functions, or another apparatus capable of forming an image on a sheet.

  The image forming apparatus 1 includes a substantially rectangular parallelepiped housing 2, a tray 600 protruding to the front side of the housing 2, and a cassette 300 disposed below the tray 600. The housing 2 accommodates various devices necessary for forming an image on a sheet (for example, elements constituting an image forming unit described later). The tray 600 is rotatably attached to the housing 2. In the following description, the position of the tray 600 protruding to the front side of the housing 2 is referred to as a first position for convenience. The user can place a sheet subjected to image forming processing by the image forming unit in the housing 2 on the tray 600 located at the first position. The tray 600 in the first position is inclined downward toward the housing 2. A concave region 21 is formed on the front wall of the housing 2. When the user rotates the tray 600 in the first position upward and brings it close to the housing 2, the tray 600 is accommodated in the recessed area 21. In the following description, the position of the tray 600 accommodated in the recessed area 21 is referred to as a second position for convenience. The tray 600 in the second position forms part of the front surface of the housing 2. The positioning portion 26 formed in the recessed area 21 suitably holds the tray 600 at the second position. An arbitrary mechanism for holding the tray 600 at a position along the wall surface of the housing 2 is employed for the positioning unit 26.

  The cassette 300 is formed to be detachable with respect to the housing 2. The user can pull out the cassette 300 from the housing 2 to the front side and store the sheet in the cassette 300. After the desired sheet is stored in the cassette 300, the user can insert the cassette 300 into the housing 2. In the following description, the sheet placed on the tray 600 is referred to as a first sheet for convenience, and the sheet accommodated in the cassette 300 is referred to as a second sheet for convenience. The image forming apparatus 1 can selectively convey the first sheet and the second sheet to the image forming unit and form a toner image on the sheet.

  An operation panel 22 is disposed above the tray 600. The user can operate the operation panel 22 to cause the image forming apparatus 1 to perform a desired operation. The operation panel 22 may include a button for adjusting the density of the toner image, for example. The image forming apparatus 1 forms a toner image on a sheet according to a user input to the operation panel 22 and an image signal (a signal including information on an image to be printed) sent from an external device (for example, a personal computer). .

  The sheet fed from the tray 600 or the cassette 300 is discharged onto the paper discharge tray 23 formed on the upper surface of the housing 2 after the toner image is formed by the image forming unit. A substantially triangular prism-shaped space is formed on the upper side of the sheet discharge tray 23, and sheets subjected to image forming processing are accumulated in the space.

  FIG. 2 schematically shows the internal structure of the image forming apparatus 1. The image forming apparatus 1 will be further described with reference to FIG. 1 in conjunction with FIG.

  The sheet conveyed from the tray 600 or the cassette 300 is guided to a conveyance path formed in the housing 2, and is supplied to an image forming unit 410 that forms a toner image on the sheet and a fixing unit 430 that fixes the toner image on the sheet. Be transported. Thereafter, the sheet is discharged onto the discharge tray 23 through the discharge unit 450.

  The conveyance path is a first sheet conveyance path that extends toward the back wall 24 of the casing 2 with the sheet feeding structure 520 that draws the first sheet into the casing 2 and feeds the sheet to the image forming unit 410 as an upstream end. 530 and a second paper feed conveyance path 310 extending upward from a downstream end (right end in FIG. 2) of the cassette 300 positioned below the first paper feed conveyance path 530. The first paper feed transport path 530 and the second paper feed transport path 310 join upstream of the registration roller pair 320 that feeds the sheet to the image forming section 410 in synchronization with the image forming process of the image forming section 410.

  The conveyance path further includes a section from the registration roller pair 320 to the fixing unit 430, a main conveyance path 330 that guides the sheet, a section from the fixing unit 430 to the discharge unit 450, and a discharge conveyance path 340 that guides the sheet. The image forming unit 410 forms a toner image on the sheet moving along the main conveyance path 330, and the fixing unit 430 fixes the toner image on the sheet. When the user causes the image forming apparatus 1 to perform single-sided printing, the discharge unit 450 discharges the sheet sent from the fixing unit 430 to the discharge conveyance path 340 to the outside of the housing 2. The discharged sheets are stacked on the paper discharge tray 23.

  When the user causes the image forming apparatus 1 to perform double-sided printing, the discharge unit 450 sends the sheet sent from the fixing unit 430 to the discharge conveyance path 340 out of the case 2 by a predetermined amount, and then enters the case 2. Perform a pullback switchback operation. The conveyance path further includes a return conveyance path 350 for guiding the sheet pulled back by the discharge unit 450. The return conveyance path 350 extends from the discharge portion 450 toward the back wall 24 of the housing 2 and then extends downward. Thereafter, the return transport path 350 extends toward the second paper feed transport path 310 and joins the second paper feed transport path 310.

  Conveyance rollers for conveying the sheet guided to these conveyance paths at appropriate positions of the first sheet conveyance path 530, the second sheet conveyance path 310, the main conveyance path 330, the discharge conveyance path 340, and the return conveyance path 350 A pair 360 is provided.

  As described above, the sheet placed on the tray 600 is sent to the first paper feed conveyance path 530 by the paper feed structure 520. The sheet feeding structure 520 is disposed so as to be able to come into contact with a lift plate 521 that pushes up the leading edge of the sheet on the tray 600 inclined downward toward the housing 2, and the leading edge of the sheet pushed up by the lift plate 521. A sheet feeding roller 522 and a separation pad 523 disposed below the sheet feeding roller 522. When the sheet feed roller 522 rotates, the sheet passes between the sheet feed roller 522 and the separation pad 523 and is fed into the first sheet feed conveyance path 530. The separation pad 523 gives a frictional force to the sheet passing between the paper feed roller 522 and the separation pad 523. Therefore, when the paper feed roller 522 tries to send a plurality of sheets to the first paper feed conveyance path 530, the separation pad 523 is other than the uppermost sheet (a sheet that directly contacts the paper feed roller 522). Friction force acting in the direction opposite to the conveyance direction is applied to the sheet, and the conveyance into the first paper feed conveyance path 530 is prevented. As a result, the sheets are fed one by one into the first paper feed conveyance path 530.

  Another cassette 300 used as another paper supply source includes a lift plate 305 that supports the second sheet. The lift plate 305 is inclined so as to push up the leading edge of the second sheet in the cassette 300. A pickup roller 311 is disposed above the downstream end of the lift plate 305. The pickup roller 311 contacts the leading edge of the second sheet pushed up by the lift plate 305. As a result, when the pickup roller 311 rotates, the second sheet is sent downstream from the cassette 300.

  A paper feed roller 312 and a separating roller 313 positioned below the paper feed roller 312 are disposed downstream of the pickup roller 311. The pickup roller 311 sends the second sheet between the paper feed roller 312 and the separating roller 313. The sheet feed roller 312 rotates to send the second sheet further downstream. On the other hand, the winding roller 313 rotates in a direction to return the second sheet to the cassette 300. Therefore, when the pickup roller 311 sends out a plurality of second sheets, the separating roller 313 pushes back the second sheet other than the uppermost sheet (the sheet that directly contacts the paper feed roller 312) to the cassette 300. As a result, the second sheet is sent to the second paper feed conveyance path 310 one by one.

  The second sheet sent to the second paper feed conveyance path 310 is sent out toward the registration roller pair 320 by a conveyance roller pair 360 provided in the second paper feed conveyance path 310. The above-described return conveyance path 350 joins upstream of the conveyance roller pair 360 of the second paper feed conveyance path 310. Accordingly, the conveyance roller pair 360 of the second paper feed conveyance path 310 also sends out the sheet supplied to the second paper feed conveyance path 310 through the return conveyance path 350 to the registration roller pair 320 in the same manner. The first paper feed transport path 530 and the second paper feed transport path 310 merge upstream of the registration roller pair 320. Accordingly, the registration roller pair 320 supplies the sheet conveyed through the first paper feed conveyance path 530 or the second paper feed conveyance path 310 to the image forming unit 410.

  The image forming unit 410 includes a yellow toner container 900Y, a magenta toner container 900M, a cyan toner container 900C, and a black toner container 900K. Below these containers, developing devices 10Y, 10M, 10C, and 10K corresponding to the respective colors of YMCK are disposed. The image forming unit 410 forms an image on a sheet using toner stored in the toner containers 900Y, 900M, 900C, and 900K.

  The image forming unit 410 includes a photoconductor drum 17 (a photoconductor on which a latent image is formed by an electrophotographic method) that carries a toner image of each color. As the photosensitive drum 17, a photosensitive drum using an amorphous silicon (a-Si) material can be used. The photosensitive drums 17 are supplied with yellow, magenta, cyan, and black toners from the toner containers 900Y, 900M, 900C, and 900K, respectively.

  Around the photosensitive drum 17, a charger 16, a developing device 10 (10Y, 10M, 10C, 10K), a transfer device (transfer roller) 19 and a cleaning device 18 are arranged. The charger 16 uniformly charges the surface of the photosensitive drum 17. The surface of the photosensitive drum 17 after charging is exposed by the exposure unit 94 to form an electrostatic latent image. For example, the exposure unit 94 irradiates a laser beam based on an image signal (a signal including image information) from an external device. The developing devices 10Y, 10M, 10C, and 10K develop the electrostatic latent images formed on the respective photosensitive drums 17 using the toners of the respective colors supplied from the toner containers 900Y, 900M, 900C, and 900K, respectively ( Visualization). The transfer roller 19 forms a nip portion with the photosensitive drum 17 across the intermediate transfer belt 921, and primarily transfers the toner image on the photosensitive drum 17 onto the intermediate transfer belt 921. The cleaning device 18 cleans the peripheral surface of the photosensitive drum 17 after the toner image is transferred.

  Each developing device 10Y, 10M, 10C, 10K includes a developing case 20. A two-component developer having a magnetic carrier and toner is accommodated in the developing case 20. Further, in the developing case 20, two stirring rollers 11 and 12 (developer stirring members) are rotatably arranged in parallel near the bottom of the developing case 20 with the longitudinal direction as an axial direction.

  A developer circulation path is set on the inner bottom surface of the developing case 20, and the stirring rollers 11 and 12 are disposed in the circulation path. A partition wall 201 erected from the bottom of the developing case 20 is provided in the axial direction between the stirring rollers 11 and 12. The partition wall 201 divides the circulation path. A circulation path is formed so as to circulate around the partition wall 201. The two-component developer is charged while being stirred and conveyed on the circulation path by the stirring rollers 11 and 12.

  The two-component developer circulates in the developing case 20 while being stirred by the stirring rollers 11 and 12, and the toner is charged. The two-component developer on the stirring roller 11 is attracted and conveyed by the magnetic roller 14 located on the upper side. The sucked two-component developer forms a magnetic brush (not shown) on the magnetic roller 14. The layer thickness of the magnetic brush is regulated by the doctor blade 13. The toner layer on the developing roller 15 is formed by a potential difference between the magnetic roller 14 and the developing roller 15. The electrostatic latent image on the photosensitive drum 17 is developed by the toner layer.

  The exposure unit 94 includes various optical system devices such as a light source, a polygon mirror, a reflection mirror, and a deflection mirror. Light based on an image signal is provided on the peripheral surface of the photosensitive drum 17 provided in each of the image forming units 410. To form an electrostatic latent image.

  The intermediate transfer unit 92 includes an intermediate transfer belt 921, a driving roller 922, and a driven roller 923. On the intermediate transfer belt 921, toner images are overcoated from a plurality of photosensitive drums 17 (primary transfer). The overcoated toner image is secondarily transferred to a sheet supplied from the cassette 300 or the tray 600 by the secondary transfer unit 98. A driving roller 922 and a driven roller 923 that rotate the intermediate transfer belt 921 are rotatably supported by the housing 2.

  The sheet fed from the registration roller 320 is supplied between the intermediate transfer belt 921 and the transfer roller 981 constituting the secondary transfer unit 98. Thereafter, the sheet is sent to the fixing unit 430 while carrying the toner image transferred by the secondary transfer unit 98.

  The fixing unit 430 includes a heating roller 432 including a heater 431 and a pressure roller 433 pressed against the heating roller 432. The sheet sent out from the secondary transfer unit 98 is sent between the heating roller 432 and the pressure roller 433. The toner on the sheet is melted by receiving heat energy from the heating roller 432 and is fixed to the sheet by receiving pressure from the pressure roller 433. After fixing the toner on the sheet, the fixing unit 430 sends the sheet to the discharge unit 450 via the discharge conveyance path 340.

  The discharge unit 450 includes a discharge roller pair 451. The discharge roller pair 451 is formed so as to be capable of normal rotation and reverse rotation. Thereby, the above-described switchback operation is achieved.

  3 and 4 are perspective views of the tray 600. FIG. The tray 600 shown in FIG. 4 is extended more than the tray 600 shown in FIG. The tray 600 will be described with reference to FIG. 1 in conjunction with FIG. 3 and FIG.

  The tray 600 has a substantially rectangular base plate 610, a substantially rectangular mounting table 630 disposed on the base plate 610, and a general plate disposed between the base plate 610 and the mounting table 630. A rectangular extension plate 650. When the tray 600 is in the first position, the main surface 611 of the base plate 610 facing the mounting table 630 and / or the extension plate 650 supports the mounting table 630 and / or the extension plate 650. When the tray 600 is in the second position, the surface 612 opposite to the main surface 611 of the base plate 610 forms the outer surface of the housing 2. When the tray 600 is in the second position, the user can place the sheet on the placing table 630 and / or the extension plate 650.

  The base plate 610 includes a pair of substantially C-shaped first rotating portions 613 that mesh with a rotating shaft (not shown) formed in the housing 2 so as to be rotatable. The base portion 610 rotates between the first position and the second position with the first rotation portion 613 as the rotation center axis. The mounting table 630 is formed at the tip of a C-shaped arm portion 631 extending in a direction away from the main surface 611 of the base plate 610 and protrudes inward in the width direction of the sheet mounted on the tray 600. A pair of columnar second rotating portions 632 is included. The second rotating part 632 is fitted into a hole (not shown) formed in the housing 2. The mounting table 630 rotates between the first position and the second position, with the second rotation unit 632 positioned above the first rotation unit 613 as a rotation center axis. In the following description, the base end portion (first base end portion) of the base plate 610 or a similar term is used for the portion of the base plate 610 on which the first rotating portion 613 is formed. For the portion of the base plate 610 facing the end, the tip of the base plate 610 or a term similar to this is used. Similarly, the base end portion (second base end portion) of the mounting base 630 or a similar term is used for the portion of the mounting base 630 where the second rotating portion 632 is formed, and the base end is opposed to the base end. For the portion of the mounting table 630 to be used, the tip portion of the mounting table 630 or a similar term is used. Similarly, the base end portion of the extension plate 650 or a similar term is used for the portion of the extension plate 650 that is on the side close to the connection portion between the tray 600 and the housing 2, and the tray 600 and the housing are used. For the portion of the extension plate 650 that is on the side far from the connection between the extension plate 650, the tip of the extension plate 650 or similar terms is used.

  The base plate 610 includes a pair of guide pieces 615 having a substantially trapezoidal cylindrical shape protruding from the main surface 611. The guide pieces 615 are aligned in the width direction of the sheets placed on the tray 600. In the following description, as shown in FIG. 3, the position of the extension plate 650 disposed on the side closer to the connection portion between the tray 600 and the housing 2 with respect to the guide piece 615 is, for convenience, the retracted position. It is called. As shown in FIG. 4, the position of the extension plate 650 where the tip edge 651 of the extension plate 650 protrudes from the tip edge 614 of the base plate 610 is referred to as a protruding position for convenience. A substantially rectangular opening 652 is formed substantially at the center of the tip of the extension plate 650. The user can move the extension plate 650 along the main surface 611 of the base plate 610 by hooking a finger on the opening 652.

  The slope 616 of the guide piece 615 facing the base end portion of the base plate 610 and / or the mounting table 630 is gradually brought into contact with the tip edge 651 of the extension plate 650 from the retracted position toward the protruding position. The guide is guided so as to be separated from the base plate 610. The upper bottom edge 617 of the guide piece 615 supports the extension plate 650 at a separated position away from the base plate 610. The extension plate 650 that is separated from the base plate 610 approaches the mounting table 630. Therefore, the extension plate 650 supported in the separated position can suitably support a sheet having a relatively long dimension in cooperation with the mounting table 630. When the guide plate 615 moves from the protruding position to the retracted position, the slope 616 of the guide piece 615 gradually guides the extension plate 650 to a close position close to the base plate 610.

  FIG. 5 is a perspective view of the base plate 610. The base plate 610 will be described with reference to FIGS. 3 and 4 in conjunction with FIG. 5.

  The base plate 610 protrudes from the main surface 611 and extends along the side edge 621 of the base plate 610 (or the side edge of the sheet placed on the tray 600), and the main surface 611. And a base wall 620 extending along the base edge 619 of the base plate 610 (or the leading edge of the sheet placed on the tray 600). Both ends of the base end wall 620 are connected to a pair of side walls 618 to form a space in which the extension plate 650 is accommodated. Upper edges 622 of the base wall 620 and the side wall 618 support the mounting table 630. A first rotating portion 613 is formed between the base end wall 620 and the base end edge 619. A slit 623 extending in the direction along the moving direction of the extension plate 650 is formed in the side wall 618. The slit 623 is used to connect the mounting table 630 and the base plate 610.

  FIG. 6 is a perspective view of the mounting table 630. The mounting table 630 will be described with reference to FIGS. 1 and 3 to 5 in conjunction with FIG.

  The mounting table 630 includes a main plate 634 that forms a mounting surface 633 on which a sheet is mounted, and a pair of side walls 635 that protrude from the mounting surface 633 and are formed along the side edges of the main plate 634. The arm portion 631 protrudes integrally with the side wall 635 and then curves so as to draw a substantially C-shaped outer contour toward the housing 2. The mounting table 630 includes a boss 637 that protrudes from the outer surface of the tip 636 of the side wall 635 (the surface facing the side wall 618 of the base plate 610). As shown in FIGS. 3 and 4, the boss 637 is inserted into the slit 623 of the base plate 610. Thus, the mounting table 630 is connected to the housing 2 and the base plate 610.

  When the user rotates the tray 600 between the first position and the second position, the base plate 610 and the mounting table 630 rotate in conjunction with each other. The meshing between the slit 623 and the boss 637 enables the interlocking between the base plate 610 and the mounting table 630, and the boss when the tray 600 is rotated between the first position and the second position. 637 moves along the slit 623. Thus, the base plate 610 and the mounting table 630 that rotate around different rotation central axes perform a rotation operation while suitably interlocking with each other.

  The front end portion of the mounting table 630 includes a front end edge 638 of the main plate 634 and a pressing piece 639 that protrudes from the front end portion 636 of the side wall 635 beyond the front end edge 638 toward the front end edge 614 of the base plate 610. In conjunction with the movement of the boss 637 along the slit 623 made during the rotation of the tray 600 between the first position and the second position, the pressing piece 639 is in relation to the extension plate 650 existing at the protruding position. It plays a role of applying a force toward the base plate 610.

  In the main plate 634, a pair of slits 640 extending in the width direction of the sheet placed on the placing table 630 is formed. A pair of sliders 641 for restricting displacement in the width direction of the sheet conveyed from the tray 600 is attached to the pair of slits 640. The slit 640 allows the slider 641 to move in the width direction of the sheet. Thus, the user can move the slider 641 on the mounting surface 633 and bring the slider 641 close to the side edge of the sheet. The central portion of the side wall 635 is recessed such that the upper edge of the side edge 633 approaches the placement surface 633. Thus, the user can easily contact the slider 641 from the side of the tray 600.

  FIG. 7 is a perspective view of the extension plate 650. The extension plate 650 will be described with reference to FIGS. 1 and 3 to 5 in conjunction with FIG.

  The base end portion of the extension plate 650 includes a substantially rectangular plate-like insertion piece 654 that protrudes from both side edges 653 of the extension plate 650. The side wall 618 of the base plate 610 includes an accommodation wall 624 that forms a substantially boot-shaped accommodation space that accommodates the fitting piece 654 in cooperation with the main surface 611 of the base plate 610. The accommodation wall 624 and the main surface 611 form a closed space protruding outward. As a result, the movable range of the extension plate 650 is determined.

  FIG. 8 is a cross-sectional view of the tray 600 including the extension plate 650 located at the protruding position protruding from the distal end portion of the base plate 610. FIG. 9 is an enlarged cross-sectional view showing a structure in the accommodation space surrounded by the accommodation wall 624 and the main surface 611 shown in FIG. The structure in the accommodation space will be described with reference to FIGS. 3 to 5 and FIG. 7 together with FIGS.

  A stopper that prevents the extension plate 650 from moving toward the tip of the base plate 610 is formed in the accommodation space. The stopper includes a first wall 625 that forms the upper contour of the receiving wall 624. A portion extending along the main surface 611 after being curved upward in the first wall 625 is used as a first clamping portion 626 that clamps the fitting piece 654 of the extension plate 650. A protruding portion 627 that protrudes toward the main surface 611 is formed on the inner surface of the accommodation wall 624 used as the first clamping portion 626. The stopper further includes a second clamping portion 628 extending from the main surface 611 toward the protruding portion 627. The second clamping part 628 extends obliquely with respect to the main surface 611 so as to guide the extension plate 650 toward the tip of the base plate 610 in a direction away from the main surface 611, and a protruding part constituting a stopper Adjacent to 627. Therefore, when the user moves the extension plate 650 from the retracted position to the protruding position, the user moves away from the main surface 611 from a proximity position close to the main surface 611 in cooperation with the guide piece 615 formed on the main surface 611. The extension plate 650 is guided to the separated position. When the extension plate 650 reaches the protruding position, the second sandwiching portion 628 is elastically deformed in a direction away from the protruding portion 627 depending on the thickness of the fitting piece 654. As a result, the fitting piece 654 is firmly held between the first clamping part 626 and the second clamping part 628. Thus, the extension plate 650 is held at the protruding position by the stopper.

  FIG. 10 is a cross-sectional view of the tray 600 including the extension plate 650 located at the protruding position protruding from the tip of the base plate 610. FIG. 11 is an enlarged cross-sectional view showing a structure around the pressing piece 639 shown in FIG. The pressing piece 639 will be described with reference to FIGS. 3 to 7 in conjunction with FIGS. 10 and 11.

  As shown in FIG. 10, the base end edge 655 of the extension plate 650 in the protruding position is close to the pressing piece 639 that forms the distal end portion of the mounting table 630. The tip edge of the pressing piece 639 includes an inclined edge 642 and a leading edge 643 formed above the inclined edge 642. The inclined edge 642 has a lower end located on the base end edge 644 side of the mounting table 630 with respect to the base end edge 655 of the extension plate 650, and the base plate extends from the lower end toward the distal end portion of the base plate 610. The base plate 610 is inclined with respect to the normal to the base plate 610 from the contact point with the base end of the extension plate 650 existing at the protruding position. Inclines towards the proximal end). The forefront edge 643 extends in a direction substantially perpendicular to the main surface 611 on the distal end side of the base plate 610 with respect to the base end edge 655 of the extension plate 650 at the protruding position.

  FIG. 12 is a cross-sectional view of the tray 600 including the extension plate 650 at the protruding position protruding from the distal end portion of the base plate 610. FIG. 12 shows the tray 600 in the middle of turning the tray 600 in the first position shown in FIG. 10 to the second position. FIG. 13 is an enlarged cross-sectional view showing the structure around the pressing piece 639 shown in FIG. The operation of the pressing piece 639 while the tray 600 is rotated from the first position to the second position will be described with reference to FIGS. 3 to 7 and FIGS. 10 and 11 together with FIGS. The

  As described above, the base plate 610 rotates upward with the first rotation portion 613 as the rotation center axis, and the mounting table 630 rotates upward with the second rotation axis 632 as the rotation center axis. As shown in FIGS. 11 and 13, the boss 637 inserted into the slit 623 is guided by the slit 623 and moves toward the tip of the base plate 610 during the upward rotation. By the movement of the boss 637 toward the distal end portion of the base plate 610, the inclined edge 642 of the pressing piece 639 comes into contact with the base end edge 655 of the extension plate 650, and the base end edge 655 of the extension plate 650 contacts the base end edge 655. A force toward the main surface 611 is applied.

  FIG. 14 is a cross-sectional view of the storage space surrounded by the storage wall 624 and the main surface 611 of the tray 600 shown in FIG. FIG. 15 is an enlarged sectional view in the accommodation space shown in FIG. The operation of the extension plate 650 resulting from the movement of the boss 637 along the slit 623 will be described with reference to FIGS. 3 and 4 and FIGS. 12 and 13 together with FIGS.

  As described with reference to FIGS. 12 and 13, the movement of the boss 637 along the slit 623 applies a force toward the main surface 611 of the base plate 610 to the base end edge 655 of the extension plate 650. As a result, the fitting piece 654 of the extension plate 650 sandwiched between the first sandwiching portion 626 and the second sandwiching portion 628 moves toward the main surface 611 of the base plate 610. As shown in FIGS. 3 and 4, the pressing piece 639 is disposed at a position close to the stopper. Therefore, the force from the pressing piece 639 is suitably transmitted to the fitting piece 654 held by the stopper. Thus, when the tray 600 is rotated from the first position to the second position, the holding of the extension plate 650 by the stopper is preferably released.

  16 and 17 are sectional views of the tray 600 rotated to the first position. FIG. 16 is a cross-sectional view of the tray 600 along the accommodation space surrounded by the accommodation wall 624 and the main surface 611. FIG. 17 is a cross-sectional view of the tray 600 along the pressing piece 639. The tray 600 rotated to the first position will be described with reference to FIG. 1 together with FIGS. 16 and 17.

  When the base plate 610 is further rotated around the first rotation unit 613 from the position shown in FIGS. 12 to 15 and the mounting table 630 is rotated around the second rotation unit 632, the tray 600 becomes the first. Reach position. As described with reference to FIGS. 12 to 15, the extension plate 650 is held by the stopper formed in the accommodation space surrounded by the accommodation wall 624 and the main surface 611 from the first position to the second position. It will be canceled while 600 is being rotated. After the holding of the extension plate 650 is released, the extension plate 650 is lowered toward the base end portion of the base plate 610 by the gravity action. The lowering of the extension plate 650 is stopped by the collision between the second wall 629 extending from the main surface 611 toward the end of the first wall 625 of the accommodation wall 624 and the fitting piece 654 of the extension plate 650.

  At this time, as shown in FIG. 17, a substantially half region from the base end portion of the extension plate 650 is disposed between the mounting table 630 and the base plate 610, and the tip end portion of the extension plate 650 is the base plate. Adjacent to the slope 616 of the guide piece 615 of the plate 610. Thus, the extension plate 650 automatically moves to the retreat position when the tray 600 is rotated from the first position to the second position. Thus, the tray 600 is preferably accommodated in the recessed area 21 formed in the housing 2.

  The present invention can be suitably applied to an image forming apparatus that forms an image on a sheet.

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus 2 ... Housing | casing 410 ... Image forming part 600 ... Tray 610 ... Base plate 611 ... Main surface 613 ... 1st base end 1st rotation part 615 formed in the part ... guide piece 618 ... side wall 623 ... slit 624 ... accommodation wall 625 ... first wall (stopper)
626 ... 1st clamping part (stopper)
627 ... Projection (stopper)
628 ... 2nd clamping part (stopper)
630... Mounting table 632... Second rotating part 637 formed on the second base end... Boss 638 .. tip end (tip end of mounting table)
639 ... Pressing piece (tip end of mounting table)
642 ... Inclined edge 650 ... Extension plate 654 ... Insertion piece

Claims (11)

A housing that houses an image forming unit that forms an image on a sheet;
Rotatably the between the second position adjacent to the housing than the first position and the first position in which the sheet supplied to the image forming unit with projecting from the housing is mounted A tray attached to the housing,
The tray includes a base plate having a first base end portion formed with a first rotation portion that is rotatably connected to the housing, and the sheet is placed at the first position and the tray. A mounting table having a second base end portion formed with a second rotating portion that is rotatably connected to the housing, and an extension plate movable along the base plate,
The base plate includes a stopper for holding the protruding position protruding the extension plate from the tip of the base plate with prevent movement of said extension plate toward the tip of the base plate,
The stopper includes a first sandwiching portion and a second sandwiching portion disposed adjacent to the first sandwiching portion,
The extension plate is inserted between the first clamping part and the second clamping part while elastically deforming at least one of the first clamping part and the second clamping part at the protruding position. Including a piece,
The extension plate held in the protruding position is in a separated position separated from the base plate,
When the tray is rotated from the first position to the second position, the tip of the mounting table applies a force toward the base plate to the extension plate, and holds the extension plate by the stopper. An image forming apparatus, wherein the image forming apparatus is released. The said 2nd clamping part is formed so that the said extension board which moves toward the said protrusion position may be guided to the said separation position from the proximity position close | similar to the said base plate. Image forming apparatus. The base plate includes a side wall protruding from a main surface facing the extension plate,
In the side wall, a slit is formed along the moving direction of the extension plate,
The mounting table includes a boss inserted into the slit,
The image forming apparatus according to claim 2, wherein the boss is movable along the slit when the tray is rotated from the first position toward the second position . The image forming apparatus according to claim 3, wherein a base end portion of the extension plate located at the protruding position is disposed at a position close to the tip end portion of the mounting table . The front end portion of the mounting table includes a front end edge extending in the width direction of the sheet, and a pressing piece protruding toward the front end portion of the base plate from the front end edge,
The image forming apparatus according to claim 4, wherein the pressing piece applies the force directed toward the base plate to the base end portion of the extension plate existing at the protruding position . An edge portion of the pressing piece is formed so as to be able to contact the base end portion of the extension plate existing at the protruding position, and a contact point with the base end portion of the extension plate with respect to a normal line of the main surface Including an inclined edge inclined in the direction of the first base end toward the base plate,
When the tray is rotated from the first position toward the second position, the boss moves toward the tip portion of the base plate, and the inclined edge exists at the protruding position. The image forming apparatus according to claim 5, wherein the force that contacts the base end portion of the extension plate and is directed toward the base plate is applied to the base end portion of the extension plate . The image forming apparatus according to claim 5, wherein the pressing piece is disposed at a position close to the stopper . The side wall includes an accommodating wall that forms a space for accommodating the fitting piece in cooperation with the main surface,
At least a part of the housing wall forms the first clamping part,
8. The second clamping part according to claim 3, wherein the second clamping part extends from the main surface toward the first clamping part and is elastically deformed by being pressed by the fitting piece of the extension plate at the protruding position. the image forming apparatus according to any one. The base plate guides the extension plate to the separated position while contacting the tip of the extension plate moving toward the protruding position, and supports the extension plate at the protruding position at the separated position. The image forming apparatus according to claim 1, further comprising a guide piece . The image forming apparatus according to claim 1, wherein the tray at the first position is inclined downward toward the housing . The image forming apparatus according to claim 1, wherein the tray is rotated upward from the first position to the second position .

Images