JP2006248679A - Image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance the operability of a paper feeding tray detachably mounted with a tray cover. <P>SOLUTION: This image forming device is provided with the paper feeding tray TR2 having inserting cover pressing parts 28a, 29a, and a pulling-out cover pressing part 31a; and the tray cover 11 moving pushed by the inserting cover pressing parts 28a, 29a following the operation of inserting the paper feeding tray TR2 longer than the paper feeding tray inserting/pulling-out direction length of an image forming device body U1, to cover a tray projecting part TR2a, projected from the image forming device body U1, of the paper feeding tray TR2, and moving pressed by the pulling-out cover pressing part 31a following the pulling-out operation of the paper feeding tray TR2, and detached from the paper feeding tray TR2 and stored inside the image forming device body U1. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus such as a printer, a FAX, a copying machine, or a multifunction machine having a plurality of functions, and more particularly to an image forming apparatus capable of mounting a paper feed tray having a size larger than the size of the image forming apparatus. .

  In the conventional image forming apparatus, the size of the main body of the image forming apparatus is also set according to the size of the paper feed tray that accommodates the maximum usable size paper. In other words, the maximum usable size of the A4 printer is set so that the size of the printer main body can also accommodate an A4-compatible paper feed tray, and the maximum size of the copier of A3 can accommodate an A3-compatible paper feed tray. The size of the copier itself was also set.

  However, in recent years, in image forming apparatuses that have been improved in performance and size, it is necessary to reduce the size of the main body of the image forming apparatus and the size of the paper feed tray. For this reason, the size of the main body of the image forming apparatus is reduced (for example, a size corresponding to A4), and a paper tray that can be resized by the user is used, so that a paper larger than the main body of the image forming apparatus (for example, A3 size) In the case of using (paper), an image forming apparatus configured such that a part of the paper feed tray protrudes from the main body of the image forming apparatus has begun to be used. In such an image forming apparatus, it is necessary for a user to attach a tray cover to a portion protruding from the main body in order to prevent dust and dust from entering the paper feed tray.

However, when attaching the tray cover, it is necessary to obtain the tray cover according to the size to be used, unpack it, and then attach it in alignment, which is a troublesome task for the user, and customer satisfaction (CS: Customer Satisfaction ) Is a problem. Also, since the image forming operation can be performed without attaching the tray cover, if the image is formed in a state where the user forgets to attach it, there is a risk of inducing trouble such as image quality deterioration or operation failure due to the entrance of dust or dust. In addition, there is a risk that quality such as image quality and reliability may be deteriorated. Furthermore, since the tray cover is a separate member from the paper feed tray, it may be lost when the tray cover is not used.
On the other hand, it is conceivable to provide a sensor or the like for detecting that the tray cover is not attached and add a function for preventing forgetting to attach, but there is a problem that the number of parts increases and the cost increases.

As techniques for solving these problems, the following techniques (1) to (4) are known.
(1) Technology for moving a paper feed tray and a tray cover in conjunction with each other Patent Document 1 (Japanese Patent Laid-Open No. 6-199429) discloses a tray cover (31) having a claw receiving portion (29), and a claw receiving portion. When the tray is inserted, the front end wall (33) of the tray cover (31) is pressed and pulled out by the paper feed tray (25) when the tray is inserted by the paper feed tray (25) having the locking claw (41) engaged with (29). A technique is described in which when the tray is pulled out, the claw receptacle (29) and the locking claw (41) are engaged to accommodate the tray cover (31) in the image forming apparatus as the tray moves. In the technique described in Patent Document 1, the user pulls out the paper feed tray (25) with a strong force in a state where the tray cover (31) is completely accommodated in the image forming apparatus. ) And the claw receiver (29) are disengaged, and only the paper feed tray (25) is removed from the image forming apparatus.
Further, in Patent Document 2 (Japanese Patent Laid-Open No. 7-179231), by utilizing the magnet's attractive force, the tray cover is linked to the paper feed tray at the time of extraction as in the technique described in Patent Document 1. A technique is described in which it is accommodated and finally pulled out with a strong force to release the adsorption by the magnet.

(2) Technology using a spring or the like Patent Document 1 and Patent Document 2, Patent Document 3 (Japanese Patent Laid-Open No. 1-172128), Patent Document 4 (Japanese Patent Laid-Open No. 5-188715), Patent Document 5 (special Japanese Patent Application Laid-Open No. 5-188715) (Kaihei 8-20448) describes a technique for connecting a spring or a winding spring to a tray cover. In this prior art, when the tray is inserted, the tray is inserted against the elastic force of the spring or the like and the tray cover is pulled out, and when the tray is pulled out, the tray cover is automatically accommodated in the image forming apparatus by the restoring force of the spring or the like. .
(3) Technique for Attaching a Tray Cover to the Image Forming Apparatus Main Body Patent Document 3 describes a technique for rotatably supporting a tray cover in an opening through which a paper feed tray of the image forming apparatus passes. In this prior art, the tray cover is pushed and rotated by the paper feed tray when the tray is inserted, and covers the upper surface of the paper feed tray. When the tray is pulled out, the tray cover is placed at a position that closes the opening for penetrating the tray. Rotate.

(4) Technology for attaching a cover to a paper feed tray In Patent Document 5, the front end of the paper feed tray in the insertion direction is rotated between an open position where paper can be easily refilled and a cover position that covers the top surface of the tray. A technique for providing a movable tray cover is described.
Further, Patent Document 6 (Japanese Patent Laid-Open No. 9-309631) discloses that a tray cover is hingedly connected to a side plate of a paper feed tray, an open position for replenishing paper, and a cover position for covering the upper surface of the paper feed tray. Is described.

JP-A-6-199429 ("0018" to "0019", "0024", FIGS. 1 and 2) JP-A-7-179231 ("0019" to "0024", FIGS. 3 and 4) JP-A-1-172128 (FIGS. 12 and 13) JP-A-5-188715 ("0017", "0028", FIGS. 1 and 4) JP-A-8-20448 (“0004”, “0014” to “0015”, “0019” to “0023”, FIGS. 1, 2 and 7) Japanese Patent Laid-Open No. 9-309631 ("0012" to "0016", FIGS. 1 and 4)

(Problems of conventional technology)
In the prior art (1), in order to release the engagement between the claw receiving portion and the locking claw and the magnet attraction, a strong force is required when the paper feed tray is pulled out, so that the operability is poor. is there.
Moreover, in the said prior art (2), since a spring etc. are provided, the number of parts increases, and there exists a problem which causes the complexity and cost increase of an apparatus. Further, since it is necessary to insert the tray against the elastic force of the spring or the like when inserting the tray, a force against the elastic force that becomes stronger with the insertion is required, and there is a problem that the operability is poor.
Further, the conventional technique (3) has a problem that the size of the tray cover is limited to the size of the tray penetrating opening, the usable paper size is limited, and the usability is poor.

In the prior art (4), since a mechanism for hinge connection and a mechanism for rotation are provided, the number of parts is increased, the apparatus is complicated, the cost is increased, and the paper feed tray becomes heavy. There is a problem that the operability is poor and the customer satisfaction is lowered.
Further, as another cover detaching technique, it is conceivable that the user slides the slidable cover provided in the image forming apparatus main body according to the size of the paper feed tray to be used, but the user's work occurs. As a result, customer satisfaction may be reduced.

  In view of the above-described circumstances, the present invention has a first technical problem to improve the operability of a paper feed tray to which a tray cover is attached and detached.

(First invention)
In order to solve the technical problem, an image forming apparatus according to a first invention is
A paper feed tray that contains a recording sheet and can be inserted into and removed from the main body of the image forming apparatus, the paper feed tray having a cover pressing portion at the time of insertion and a cover pressing portion at the time of extraction,
A tray cover that is movably supported inside the image forming apparatus main body, the cover pressing during insertion being accompanied by an insertion operation of the paper feeding tray that is longer than the length of the image forming apparatus main body in the paper feeding tray insertion / extraction direction The tray is pushed and moved to cover the tray protruding portion that protrudes from the image forming apparatus main body of the paper feed tray, and is pressed against the cover pressing portion at the time of withdrawal as the paper feed tray is pulled out. The tray cover that is moved and detached from the paper feed tray and accommodated inside the image forming apparatus main body,
It is provided with.

(Operation of the first invention)
In the image forming apparatus according to the first aspect of the present invention, the tray cover that is movably supported inside the image forming apparatus main body is longer than the length of the image forming apparatus main body in the paper feed tray insertion / extraction direction. As the tray is inserted, the tray is pushed by the cover pressing portion during insertion of the paper feed tray and moves to cover the tray protruding portion of the paper feed tray that protrudes from the image forming apparatus main body. Further, the tray cover is moved by being pushed by the cover pressing portion when the paper feed tray is withdrawn, and detached from the paper feed tray along with the operation of pulling out the paper feed tray. Is housed in.

  Therefore, in the image forming apparatus according to the first aspect of the invention, when the paper feed tray that is longer than the length of the image forming apparatus main body in the paper feed tray insertion / extraction direction is used, the tray cover is automatically inserted only by the user inserting / extracting in the insertion / extraction direction. Is removed. As a result, the user can omit the work of mounting the tray cover on the sheet feeding tray by himself, thereby improving the operability. Further, since the tray cover is automatically attached, it is possible to prevent the tray cover from being forgotten to be attached, and to reliably prevent dust and dust from entering. Therefore, the possibility of inducing trouble during image formation is reduced, and the quality can be maintained. Further, since the tray cover is accommodated inside the image forming apparatus main body, it is possible to prevent the tray cover from being lost. As a result, the image forming apparatus according to the first aspect of the invention can improve the operability of the paper feed tray and improve customer satisfaction.

(First Embodiment 1)
The image forming apparatus according to Embodiment 1 of the first invention is the image forming apparatus according to the first invention, wherein
A cover support base supported by the main body of the image forming apparatus that supports the tray cover so as to be slidable;
It is provided with.
(Operation of Form 1 of the First Invention)
In the image forming apparatus according to the first aspect of the first invention having the above-described structural requirements, the cover support base supported by the image forming apparatus main body supports the tray cover so as to be slidable. Therefore, the tray cover is slid on the cover support base and attached to and detached from the paper feed tray.

(First Embodiment 2)
An image forming apparatus according to a second aspect of the present invention is the first aspect of the first aspect of the present invention.
An accommodating support portion that supports the tray cover in a state in which the tray cover is accommodated in the image forming apparatus main body, a cover guide portion that guides the tray cover that moves in accordance with the insertion / extraction operation of the paper feed tray, The cover support,
It is provided with.
(Operation of the second aspect of the first invention)
In the image forming apparatus according to the second aspect of the first invention having the above-described configuration requirements, the support portion of the cover support base that supports the tray cover supports the tray cover in a state where the tray cover is stored inside the image forming apparatus main body. . The cover guide unit guides the tray cover that moves as the paper feed tray is inserted and removed. Therefore, the tray cover is guided by the cover guide portion and is attached to and detached from the paper feed tray.

(Embodiment 3 of the first invention)
An image forming apparatus according to a third aspect of the present invention is the second aspect of the first aspect of the present invention.
When the tray cover moves to the inside of the image forming apparatus main body as the paper feeding tray is pulled out, the tray cover is moved from the cover guide portion to the support portion at the time of accommodation by the weight of the tray cover. The cover support base having a curved shape to be moved;
It is provided with.
(Operation of the third aspect of the first invention)
In the image forming apparatus according to the third aspect of the first invention having the above-described structural requirements, the tray cover is moved when the tray cover moves to the inside of the image forming apparatus main body along with the operation of extracting the paper feed tray. Due to the weight of the tray cover, the tray cover is moved from the cover guide portion to the support portion during storage.

(First aspect 4)
An image forming apparatus according to a fourth aspect of the first invention is the same as that according to the third aspect of the first invention.
A damping member that engages with the tray cover that moves from the cover guide portion to the support portion when housed to suppress vibration of the tray cover,
It is provided with.
(Operation of the fourth aspect of the first invention)
In the image forming apparatus according to the fourth aspect of the first invention having the above-described structural requirements, the vibration damping member engages with the tray cover that moves from the cover guide portion to the support portion when accommodated, and vibrates the tray cover. Suppress. Therefore, vibration and noise can be reduced.

(First embodiment 5)
An image forming apparatus according to a fifth aspect of the first invention is the image forming apparatus according to any one of the first invention and the first to fourth aspects of the first invention.
The insertion cover pressing portion provided on the sheet extraction direction side wall of the sheet feeding tray, and the extraction cover pressing portion provided on the rear end wall of the sheet feeding direction of the sheet feeding tray, Paper tray,
It is provided with.
(Operation of the fifth aspect of the first invention)
In the image forming apparatus according to the fifth aspect of the first invention having the above-described structural requirements, the cover pressing portion at the time of insertion is provided on the side wall in the sheet extraction direction of the sheet feeding tray. The pull-out cover pressing portion is provided on the rear end wall of the sheet feeding tray in the sheet pulling direction.

(First embodiment 6)
An image forming apparatus according to a sixth aspect of the first invention is the image forming apparatus according to any one of the first invention and the first to fifth aspects of the invention,
The paper feed tray disposed at a position where the placement position of the cover pressing portion at the time of insertion and the placement position of the cover press portion at the time of removal do not overlap with each other in the paper feed tray insertion / extraction direction;
It is provided with.
(Operation of the sixth aspect of the first invention)
In the image forming apparatus according to the sixth aspect of the first invention having the above-described structural requirements, the arrangement position of the cover pressing portion at the time of insertion and the arrangement position of the cover pressing portion at the time of extraction do not overlap with each other in the paper feed tray insertion / extraction direction. Has been placed.

(First embodiment 7)
An image forming apparatus according to a seventh aspect of the first invention is the image forming apparatus according to any one of the first invention and the first to sixth aspects of the invention,
The paper feed tray having an engaging recess for locking the tray cover;
The tray cover having an engaging portion that engages with the engaging recess when the paper feeding tray is attached and detached, and moves the tray cover integrally with the paper feeding tray;
It is provided with.
(Operation of the first aspect 7)
In the image forming apparatus according to the seventh aspect of the first invention having the above-described structural requirements, the engagement protrusion of the tray cover is engaged with the engagement recess of the paper feed tray when the paper feed tray is attached or detached. Therefore, the tray cover and the paper feed tray can move together.

In the above-described present invention, since the tray cover can be automatically attached and detached without the user performing work, the operability can be improved.
In addition, since the operability is improved according to the present invention, customer satisfaction can be increased.
Furthermore, since the tray cover is automatically attached, dust and dust can be prevented from entering, and troubles during image formation can be reduced. Therefore, quality can be maintained.

Next, specific examples (examples) of the embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following examples.
In order to facilitate understanding of the following description, in the drawings, the front-rear direction is the X-axis direction, the left-right direction is the Y-axis direction, the up-down direction is the Z-axis direction, and arrows X, -X, Y, -Y, The direction indicated by Z and -Z or the indicated side is defined as the front side, the rear side, the right side, the left side, the upper side, the lower side, or the front side, the rear side, the right side, the left side, the upper side, and the lower side, respectively.
In the figure, “•” in “○” means an arrow heading from the back of the page to the front, and “×” in “○” is the front of the page. It means an arrow pointing from the back to the back.

FIG. 1 is an overall perspective view of an image forming apparatus including a paper feed tray according to a first embodiment of the present invention.
In FIG. 1, a printer U as an image forming apparatus according to the first exemplary embodiment includes a printer main body (image forming apparatus main body) U1, a process cartridge U2 and a fixing unit U3 that are detachably supported with respect to the printer main body U1. .
The printer body U1 includes a controller C constituted by a microcomputer, an IPS (image processing system) whose operation is controlled by the controller C, a laser drive circuit DL, a power supply device E, and the like. The power supply device E applies a bias voltage to a charging roller CR, a developing roller Ga, a transfer roller Tr, and the like which will be described later.
The IPS (image processing system) converts print data input from an external host computer or the like into image data for forming a latent image and outputs it to the laser drive circuit DL at a predetermined timing. The laser drive circuit DL outputs a laser drive signal to the ROS (latent image forming apparatus) according to the input image data.

  The process cartridge U2 has an image carrier unit U2a and a developing unit U2b. The image carrier unit U2a of the process cartridge U2 includes an image carrier PR, a charging roller CR, and a toner recovery container (cleaner) CL that rotatably supports them. The developing unit U2b has a developing container V, and a developing roller Ga and a developer stirring member Gb are rotatably supported in the developing container V. A developer cartridge K is detachably attached to the developer container V. Inside the developer cartridge K, a stirring and conveying member Gc that conveys the developer to the developer stirring member Gb while stirring the developer is rotatably supported.

The surface of the rotating image carrier PR is charged by the charger (charge corotron) CC in the charging region Q1, and by the laser beam L emitted from the ROS (latent image writing device) at the latent image writing position Q2. An electrostatic latent image is written. The electrostatic latent image is developed into a toner image by the developing roller Ga of the developing unit U3b in the developing area Q3, and the recording sheet is formed by the transfer roller Tr in the transfer area Q4 formed by the pressure contact area between the image carrier PR and the transfer roller Tr. S is transferred to S. The residual toner on the surface of the image carrier PR is removed (scraped) by the cleaning blade CB in the cleaning area Q5 on the downstream side of the transfer area Q4, and is collected in the toner collection container CL.
A film seal FS is provided on the opposite side of the cleaning blade CB, and the film seal FS prevents the toner collected in the toner collection container CL from spilling out.

A lower part of the printer main body U1 is configured to be able to be inserted into and removed from the printer main body U1 in the left-right direction (Y-axis direction, see the arrow in FIG. 1). ) TR1 and TR2 are installed. Note that the length in the tray insertion / removal direction (left-right direction, Y-axis direction) of the printer main body U1 of the first embodiment is set to a length corresponding to the A4 size that is frequently used. Therefore, when using the paper feed tray TR2 that accommodates the recording sheet S of a size larger than the A4 size (LGL (legal) size, A3 size, etc.), as shown in the lower paper feed tray TR2 in FIG. A part of the paper feed tray TR2 protrudes through the printer body U1.
The recording sheets (sheets) S taken out from the paper feed trays TR1 and TR2 by the pickup roller Rp are separated one by one by the separating roller Rs and conveyed by the conveying roller Ra arranged along the sheet conveying path SH. Then, the sheet is conveyed to the transfer area Q4 at a predetermined timing by a registration roller Rr disposed upstream of the transfer area Q4 in the sheet conveyance direction.

The transfer roller Tr to which a transfer bias is applied at a predetermined timing from the power supply device E whose operation is controlled by the controller C transfers the toner image on the image carrier PR to the recording sheet S passing through the transfer region Q4.
The recording sheet S on which the toner image is transferred in the transfer area Q4 is conveyed to the fixing unit U3 with the toner image unfixed. The fixing unit U3 includes a fixing device F including a pair of fixing rollers Fh and Fp, and a fixing region Q6 is formed by a pressure contact region between the pair of fixing rollers Fh and Fp. The recording sheet S conveyed to the fixing unit U3 is fixed with a toner image by a pair of fixing rollers Fh and Fp of the fixing device F in the fixing region Q6. The recording sheet S on which the fixing toner image is formed is guided by sheet guides SG1 and SG2, and is discharged from the sheet discharge roller (sheet conveyance roller) Rh to the sheet discharge tray TRh on the upper surface of the printer body U1.

(Description of tray cover attachment / detachment structure)
FIG. 2 is an explanatory diagram of the positional relationship between the paper feed tray and the tray cover according to the first embodiment. FIG. 2A is a plan view of a paper feed tray and a tray cover portion corresponding to A4 size, and FIG. 2B is IIB-IIB in FIG. 2C is a plan view of the LGL size compatible paper feed tray and tray cover portion, and FIG. 2D is a diagram viewed from IID-IID in FIG. 2C.
3A and 3B are perspective views for explaining a main part for explaining the mounting of the LGL size paper feed tray to the image forming apparatus. FIG. 3A is a diagram for explaining the state before the mounting, and FIG. is there.
1 and 2, the printer main body U1 has a front frame U1a, a rear frame U1b, a left frame U1c, and a right frame U1d. Paper feed trays TR1 and TR2 are inserted and removed between the front frame U1a and the rear frame U1b. (See FIG. 2). The right frame U1d and the left frame U1c are formed with openings 1 and 2 through which the paper feed trays TR1 and TR2 pass and penetrate when they are attached and detached. 1 to 3, a plate-like damping member 3 protruding inside the printer U is fixedly supported above the opening 2 of the left frame U1c.

  1 to 3, a pair of front and rear cover support bases (cover support members) 6 and 7 are fixedly supported inside the front frame U1a and the rear frame U1b. The cover support bases 6 and 7 are provided with stopper portions 6a and 7a formed so as to protrude to the upper right, and a support portion 6b formed when the stopper portions 6a and 7a are inclined upward from the left end of the stopper portions 6a and 7a. , 7b and cover guide portions 6c, 7c formed so as to incline downward from the left end of the support portions 6b, 7b. Connection portions between the support portions 6b and 7b and the cover guide portions 6c and 7c are formed in a smooth curved shape. The front ends (the lower left end, the rear end in the tray extraction direction) of the cover guide portions 6c and 7c extend below the height of the upper ends of the paper feed trays TR1 and TR2. Note that the pair of front and rear cover supporters 6 and 7 are disposed outside the sheet trays TR1 and TR2 in the sheet width direction (direction perpendicular to the tray insertion / extraction direction) (see FIGS. 2A and 2C). Further, the interval between the cover support bases 6 and 7 and the vibration damping member 3 is set to an interval through which a tray cover 11 described later can pass.

A tray cover 11 is slidably supported on the cover support bases 6 and 7. The tray cover 11 slides to a position covering the paper feed tray TR2 when the paper feed tray TR2 is mounted (see FIGS. 2C and 2D). The tray cover 11 has a resin plate-like (thin plate-like) cover main body 12, and is supported by the cover support bases 6 and 7 on the lower surfaces of both front and rear end portions (end portions in the tray insertion / extraction direction) of the cover main body 12. A supported surface 13 is provided. A pair of front and rear ribs 14 projecting downward is formed on the lower surface of the cover body 12 inside the supported surface 13 with an interval similar to the inner width of the paper feed trays TR1 and TR2. On both front and rear ends of the left end portion of the cover body 12, tray engaging projections 16 (only the front side is shown and the rear side is not shown) are formed.
When the tray cover 11 is housed in the printer body U1, the tray cover 11 is supported by the housing support portions 6b and 7b and is held in a state where the upper surface of the left end portion is close to or in contact with the vibration damping member 3.

  1 to 3, paper feed trays TR <b> 1 and TR <b> 2 that can be attached to and detached from the printer main body U <b> 1 have a tray main body 21 in which the recording sheet S is accommodated. A cover case 23 for a user to hold when inserting and removing the paper feed trays TR1 and TR2 is supported on the right end wall (tray extraction direction front end wall) 22 of the tray body 21. The cover case 23 is formed with a sheet passage slit 23a through which the recording sheet S fed from the lower paper feed tray passes. A sheet lifting plate 26 is supported on the bottom wall 24 of the tray body 21 to lift the front end of the stacked recording sheets S in the sheet feeding direction to a height at which sheet feeding is possible.

  2C and 2D, the front and rear end walls (tray insertion / removal side end walls) 28, 29 of the LGL size-compatible sheet feeding tray TR2 have cover insertion protrusions (insertion cover pressing portions) protruding upward. 28a and 29a are formed. The cover pressing protrusions 28a and 29a at the time of insertion in the first embodiment are set to positions and heights at which the ribs 14 of the tray cover 11 can be engaged. Further, the positions of the cover pressing protrusions 28a and 29a in the tray insertion / removal direction correspond to the size of the printer body U1 in the tray insertion / removal direction, and from the right end of the paper feed tray TR2 to the cover pressing protrusions 28a and 29a at the time of insertion. The length is set similarly to the length of the printer body U1 in the tray insertion / extraction direction.

  Engagement recesses 28b and 29b (see FIG. 3A) into which the tray engagement protrusion 16 is fitted when the tray cover 11 is mounted on the left end portion (rear end portion in the tray extraction direction) of the front and rear end walls 28 of the paper feed tray TR2. ) Is formed. At the center of the left end wall (rear end wall in the tray extraction direction) 31 of the paper feed tray TR2, an extraction-time cover pressing portion 31a protruding upward is formed. Therefore, in the paper feed tray TR2 of the first embodiment, the insertion cover pressing protrusions 28a and 29a and the extraction cover pressing portion 31a are arranged at positions that do not overlap with the sheet insertion / extraction direction (FIG. 2A, (See FIG. 2C). In addition, the height of the cover pressing portion 31a at the time of extraction in the first embodiment is higher than the upper surface of the tray cover 11 when the tray cover 11 is mounted, and the tray supported by the cover support bases 6 and 7 when the tray cover 11 is not mounted. It is set below the height of the lower surface of the cover body 12 of the cover 11 (see FIGS. 2B and 2D).

  2A and 2B, in the paper feed tray TR1 corresponding to the A4 size (standard size), the positions of the cover pressing protrusions 28a and 29a at the time of insertion are such that the paper feed tray TR1 is mounted on the printer body U1. It is set so as to be located on the right side of the right end of the tray cover 11 supported by the cover support bases 6 and 7.

(Operation of Example 1)
In the printer (image forming apparatus) U of Embodiment 1 having the above-described configuration, insertion / extraction of the paper feed tray TR2 and attachment / detachment of the tray cover 11 will be described.
(Description of paper tray mounting operation (insertion operation))
FIG. 4 is an explanatory diagram for explaining the relationship between the paper feed tray and the tray cover when the paper feed tray of the image forming apparatus according to the first exemplary embodiment is mounted. FIG. 4A is an explanatory diagram of a state in which the mounting is started, and FIG. FIG. 4C is an explanatory diagram of a state where the cover pressing portion is engaged with the tray cover at the time of insertion, FIG. 4C is an explanatory diagram of a state where the paper feed tray is pushed in from the state of FIG. 4B, and FIG. 4E is an explanatory diagram of a state in which the tray cover has reached the upper surface of the paper feed tray, and FIG. 4F is an explanatory diagram of a state in which the tray cover is mounted on the paper feed tray.

  3 and 4, when the paper feed tray TR2 is attached to the printer body U1, when the user inserts the paper feed tray TR2 from the right side to the left side (tray insertion direction), the cover pressing projections 28a and 29a are inserted. Engages with the rib 14 (see FIG. 4B). In this state, when the paper feed tray TR2 is further inserted, it is pressed by the cover pressing protrusions 28a and 29a at the time of insertion, and the tray cover 11 slides and moves on the support portions 6b and 7b at the time of storage (see FIG. 4C). . When the paper feed tray is further pushed in, the tray cover 11 is rotated by its own weight (see FIG. 4D), guided on the cover guide portions 6c and 7c, and moved onto the paper feed tray TR2 (see FIG. 4E). . At this time, the engagement protrusion 16 of the tray cover 11 is fitted into the engagement recesses 28b and 29b, and the tray cover 11 moves integrally with the paper feed tray TR2. When the paper feed tray TR2 is pushed to the end, a portion of the paper feed tray TR2 that protrudes from the printer body U1 (tray protruding portions, cover pressing projections 28a, 29a to left end portions) TR2a (See FIG. 4F).

In the tray cover 11 of the first embodiment, the rib 14 of the tray cover 11 is fitted inside the front and rear end walls 28 and 29 of the paper feed tray TR2 in a state where the tray cover 11 is mounted on the paper feed tray TR2. The engagement protrusion 16 of the tray cover 11 is fitted in the engagement recesses 28b and 29b. Accordingly, the tray cover 11 is mounted on the paper feed tray TR1 in a state of being aligned.
Therefore, in the printer U according to the first embodiment, when the paper feed tray TR2 larger than the printer main body U1 is used, the tray cover 11 is automatically aligned when the user simply inserts the paper feed tray TR2. Is mounted on the tray protrusion TR2a. When the paper feed tray TR1 having the same size (standard size) as the printer main body U1 is used, the cover pressing projections 28a and 29a do not engage with the ribs 14 when inserted, so that the tray cover 11 is accommodated inside the printer main body U1. It is held in the state.

(Description of paper tray removal operation (extraction operation))
FIG. 5 is an explanatory diagram for explaining a relationship between a paper feed tray and a tray cover when the paper feed tray of the image forming apparatus according to the first exemplary embodiment is pulled out. FIG. 5A is an explanatory diagram of a state before being pulled out. FIG. 5C is an explanatory diagram of a state immediately after the start of the extraction operation, FIG. 5C is an explanatory diagram of a state in which the right end of the tray cover is approaching the support portion when stored, and FIG. 5E is an explanatory diagram of a state in which the tray cover has started to rotate due to its own weight, FIG. 5F is an explanatory diagram of a state in which the tray cover is further rotated, and FIG. 5G is a tray cover. FIG. 5H is an explanatory diagram of a state in which the tray cover is completely detached from the paper feed tray.

  In FIG. 5, in order to remove the paper feed tray TR2 mounted on the printer main body U1, when the user starts to pull out from the left side to the right side (tray extraction direction), the supported surface 13 of the tray cover 11 becomes the cover guide portion. Engages 6c and 7c. When the paper feed tray TR2 is pulled out in this state, it is guided by the cover guide portions 6c and 7c, and the right end portion (front end portion in the pulling direction) of the tray cover 11 starts to be detached from the paper feed tray TR2 (see FIG. 5B). ). When the paper feed tray TR2 is further extracted in this state, the tray cover 11 moves to the upper right while being guided by the cover guide portions 6c and 7c (see FIGS. 5C and 5D). When the center of gravity of the tray cover 11 moves from the cover guide portions 6c and 7c to the support portions 6b and 7b when stored, the tray cover 11 starts to rotate due to its own weight (see FIGS. 5D to 5F). Even when the tray cover 11 starts to rotate, the left end (rear end in the extraction direction) of the tray cover 11 is pressed by the extraction pressing portion 31a having a predetermined height, and the tray cover 11 moves in the extraction direction. .

Further, when the paper feed tray TR2 is pulled out and the tray cover 11 is rotated and the engagement with the pressing portion 31a is released, the tray cover 11 is supported by the support portions 6b and 7b when stored. At this time, since the upper surface of the left end portion of the tray cover 11 is restrained by the vibration damping member 3 (see FIG. 5G), the tray cover 11 is in a state in which vibration (fluttering, wobble, etc.) is reduced, 7b is supported. In addition, since the support portions 6b and 7b at the time of storage are inclined upward to the left, even if the tray cover 11 moves rightward (slides) on the support portions 6b and 7b at the time of storage, the stopper portions 6a, The movement is restricted by 6b, and the tray cover 11 is held at a predetermined position.
Therefore, when the paper feed tray TR2 to which the tray cover 11 is attached is pulled out, the user simply pulls out the paper feed tray TR2 in the tray pulling direction, and the tray cover 11 is automatically removed from the paper feed tray TR2. Housed in the printer body U1.

Therefore, in the printer U according to the first exemplary embodiment, the tray cover 11 is automatically attached and detached simply by the user inserting and removing the paper feed tray in the insertion direction or the extraction direction. As a result, the user can omit the work of mounting the tray cover on the sheet feeding tray by himself, thereby improving the operability. In addition, since the tray cover 11 is automatically attached, it is possible to prevent the tray cover 11 from being forgotten to be attached and to reliably prevent dust and dust from entering. Therefore, the possibility of inducing trouble during image formation is reduced, and the quality can be maintained.
Further, unlike the prior art, it is not necessary to insert and remove with a strong force in order to remove the engagement between the tray cover and the paper feed tray and the adsorption by the magnet, so that the operability is improved. Furthermore, since there is no spring or the like for pulling the tray cover as in the prior art, it is possible to prevent an increase in the number of parts, a complicated configuration, and an increase in cost. Moreover, since it does not insert / extract against the elastic force of a spring etc. like the prior art, insertion / extraction can be performed smoothly and operativity improves.

Further, since the tray cover 11 is accommodated in the printer body U1 and is not supported by the paper feed tray TR2 when the paper feed tray is removed, the paper feed tray TR2 can be reduced in weight and the operability is improved. Further, since the tray cover 11 is accommodated inside the printer main body U1, the tray cover 11 can be prevented from being lost.
Furthermore, since the tray cover 11 of Example 1 is formed of resin and no extra members are loaded, manufacturing is easy and costs can be reduced.
As a result, the printer U according to the first embodiment can realize a tray cover attaching / detaching mechanism with a simple configuration and low cost, and can improve operability and customer satisfaction.

(Example of change)
As mentioned above, although the Example of this invention was explained in full detail, this invention is not limited to the said Example, A various change is performed within the range of the summary of this invention described in the claim. It is possible. Modification examples (H01) to (H09) of the present invention are exemplified below.
(H01) The present invention is not limited to a printer, and can be applied to an image forming apparatus such as a copying machine, a FAX, or a multifunction machine. Further, the present invention is not limited to a monochrome image forming apparatus, and can be applied to a color image forming apparatus. Furthermore, the present invention is not limited to an electrophotographic image forming apparatus, and can be applied to an image forming apparatus of another recording system (for example, an ink jet recording system). Further, the number of paper feed trays is not limited to two, and the present invention can be applied to an image forming apparatus having one or three or more stages.

(H02) In the above embodiment, the damping member 3 can be omitted.
(H03) In the above-described embodiment, the material of the tray cover 11 is not limited to the resin, and can be composed of various materials other than the resin. Further, the rib 14 can be omitted.
(H04) In the above-described embodiment, the cover pressing protrusions 28a and 29a at the time of insertion are also provided in the A4 size paper feed tray, but it is possible to omit them.

(H05) In the above-described embodiment, the A4 size compatible paper feed tray TR1 and the LGL size compatible paper feed tray TR2 are exemplified, but the present invention is not limited to this combination, and a paper feed tray of any size according to the design. It is also possible to use a tray cover. It is also possible to use a paper feed tray whose size can be adjusted by the user. In this case, a tray cover having a size corresponding to the maximum changeable size can be used.
(H06) In the above embodiment, the engagement protrusion 16 and the engagement recesses 28b and 29b can be omitted.
(H07) In the above-described embodiment, the support portions 6b and 7b at the time of accommodation are formed so as to be inclined upward toward the left, but may be formed flat (flat).

(H08) In the above-described embodiment, the cover support bases 6 and 7 are provided at both front and rear ends, but can be provided at any position, for example, at the center. For example, when it is provided in the center portion, the position of the cover pressing portion 31a at the time of extraction can be moved to the outside or the shape can be changed.
(H09) In the above embodiment, the cover guide portions 6c, 7c are formed in a smooth curved shape, but the tips of the cover guide portions 6c, 7c extend below the height of the upper ends of the paper feed trays TR1, 2. If it is, it is also possible to form in the linear shape of a downward slope toward the left.

FIG. 1 is an overall perspective view of an image forming apparatus including a paper feed tray according to a first embodiment of the present invention. FIG. 2 is an explanatory diagram of the positional relationship between the paper feed tray and the tray cover according to the first embodiment. FIG. 2A is a plan view of a paper feed tray and a tray cover portion corresponding to A4 size, and FIG. 2B is IIB-IIB in FIG. 2C is a plan view of the LGL size compatible paper feed tray and tray cover portion, and FIG. 2D is a diagram viewed from IID-IID in FIG. 2C. 3A and 3B are perspective views for explaining a main part for explaining the mounting of the LGL size paper feed tray to the image forming apparatus. FIG. 3A is a diagram for explaining the state before the mounting, and FIG. is there. FIG. 4 is an explanatory diagram for explaining the relationship between the paper feed tray and the tray cover when the paper feed tray of the image forming apparatus according to the first exemplary embodiment is mounted. FIG. 4A is an explanatory diagram of a state in which the mounting is started, and FIG. FIG. 4C is an explanatory diagram of a state where the cover pressing portion is engaged with the tray cover at the time of insertion, FIG. 4C is an explanatory diagram of a state where the paper feed tray is pushed in from the state of FIG. 4B, and FIG. 4E is an explanatory diagram of a state in which the tray cover has reached the upper surface of the paper feed tray, and FIG. 4F is an explanatory diagram of a state in which the tray cover is mounted on the paper feed tray. FIG. 5 is an explanatory diagram for explaining a relationship between a paper feed tray and a tray cover when the paper feed tray of the image forming apparatus according to the first exemplary embodiment is pulled out. FIG. 5A is an explanatory diagram of a state before being pulled out. FIG. 5C is an explanatory diagram of a state immediately after the start of the extraction operation, FIG. 5C is an explanatory diagram of a state in which the right end of the tray cover is approaching the support portion when stored, and FIG. 5E is an explanatory diagram of a state in which the tray cover has started to rotate due to its own weight, FIG. 5F is an explanatory diagram of a state in which the tray cover is further rotated, and FIG. 5G is a tray cover. FIG. 5H is an explanatory diagram of a state in which the tray cover is completely detached from the paper feed tray.

Explanation of symbols

3 ... damping member,
6, 7 ... Cover support,
6b, 7b ... Supporting portion when accommodated,
6c, 7c ... cover guide part,
11 ... Tray cover,
16 ... engaging protrusion,
28, 29 ... Sheet extraction direction side wall,
28a, 29a ... Cover pressing part at the time of insertion,
28b, 29b ... engaging recess,
31 ... rear end wall in the sheet extraction direction,
31a: Cover pressing part at the time of extraction,
S ... Recording sheet,
TR1, TR2 ... paper feed tray,
TR2a ... Tray protrusion U1 ... Image forming apparatus main body.

Claims (8)

A paper feed tray that contains a recording sheet and can be inserted into and removed from the main body of the image forming apparatus, the paper feed tray having a cover pressing portion at the time of insertion and a cover pressing portion at the time of extraction,
A tray cover that is movably supported inside the image forming apparatus main body, the cover pressing during insertion being accompanied by an insertion operation of the paper feeding tray that is longer than the length of the image forming apparatus main body in the paper feeding tray insertion / extraction direction The tray is pushed and moved to cover the tray protruding portion that protrudes from the image forming apparatus main body of the paper feed tray, and is pressed against the cover pressing portion at the time of withdrawal as the paper feed tray is pulled out. The tray cover that is moved and detached from the paper feed tray and accommodated inside the image forming apparatus main body,
An image forming apparatus comprising: A cover support base supported by the main body of the image forming apparatus that supports the tray cover so as to be slidable;
The image forming apparatus according to claim 1, further comprising: An accommodating support portion that supports the tray cover in a state in which the tray cover is accommodated in the image forming apparatus main body, a cover guide portion that guides the tray cover that moves in accordance with the insertion / extraction operation of the paper feed tray, The cover support,
The image forming apparatus according to claim 2, further comprising: When the tray cover moves to the inside of the image forming apparatus main body as the paper feeding tray is pulled out, the tray cover is moved from the cover guide portion to the support portion at the time of accommodation by the weight of the tray cover. The cover support base having a curved shape to be moved;
The image forming apparatus according to claim 3, further comprising: A damping member that engages with the tray cover that moves from the cover guide portion to the support portion when housed to suppress vibration of the tray cover,
The image forming apparatus according to claim 4, further comprising: The insertion cover pressing portion provided on the sheet extraction direction side wall of the sheet feeding tray, and the extraction cover pressing portion provided on the rear end wall of the sheet feeding direction of the sheet feeding tray, Paper tray,
The image forming apparatus according to claim 1, further comprising: The paper feed tray disposed at a position where the placement position of the cover pressing portion at the time of insertion and the placement position of the cover press portion at the time of removal do not overlap with each other in the paper feed tray insertion / extraction direction;
The image forming apparatus according to claim 1, further comprising: The paper feed tray having an engaging recess for locking the tray cover;
The tray cover having an engaging portion that engages with the engaging recess when the paper feeding tray is attached and detached, and moves the tray cover integrally with the paper feeding tray;
The image forming apparatus according to claim 1, further comprising:

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