JP7251411B2 - MEDIUM PLACEMENT DEVICE AND IMAGE FORMING APPARATUS - Google Patents

Description

The present invention relates to a medium stacking device and an image forming apparatus, and is suitable for application to, for example, a tray for stacking sheets ejected from the image forming apparatus.

2. Description of the Related Art Conventionally, in an image forming apparatus, an image is formed while paper is conveyed along a conveying path formed inside, and the paper on which the image is formed (that is, printed) is conveyed to a paper discharge tray. Therefore, a system in which the paper is placed on the tray is widely used.

This tray is composed of a combination of a plurality of parts, and is unfolded when used to secure a required size, and when not used, each part is appropriately folded or stacked to be miniaturized and stored in the device main body. there is something Such a tray must be small when folded, large enough to hold paper when unfolded, easy to switch between stored and used, and simple in structure. It is required to have sufficient strength.

Therefore, as an image forming apparatus, an apparatus has been proposed in which a tray (manual tray) is opened and closed with respect to the apparatus main body and a sub-tray (extension member) is rotated with respect to the opened tray to expand or retract the tray. (See Patent Document 1, for example).

Japanese Patent Application Laid-Open No. 2004-345833 (Fig. 5, etc.)

By the way, in the image forming apparatus described above, the range in which the sub-tray can be rotated with respect to the tray may be restricted. For example, the sub-tray can be expanded by a predetermined member provided on the tray so that the longitudinal direction is aligned with the paper transport direction, and rotated about 90 degrees from the expanded state so that the longitudinal direction is orthogonal to the transport direction. In some cases, it is rotatable only between the retracted state and the retracted state.

In some image forming apparatuses, the tray is configured to be rotatable with respect to the main body as in Japanese Patent Application Laid-Open No. 2002-200012, and the surface on which the paper is placed faces the vertical direction in the storage state. At this time, the sub-tray can be rotated upward, but the downward rotation is restricted, so that the storage state can be maintained without rotating against the action of gravity.

However, in some image forming apparatuses, for example, when the tray is divided into two parts in the transport direction and configured to be foldable, the sub-tray in the accommodated state can be rotated downward. In such an image forming apparatus, there is a possibility that the sub-tray may rotate from the stored state while the tray is stored, and the tray may not be stored normally.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above points, and proposes a medium placement device and an image forming apparatus that can maintain a good storage state and realize good operability.

In order to solve such a problem, in the medium stacking device of the present invention, a medium transported along a transport path connected to the main body is placed in a root direction approaching the main body or in a leading end direction away from the main body. The length in the transport direction along the transport path is obtained by causing at least a part of the extension facing surface of the placement body and the placement opposing surface of the placement body to face each other and changing the position and posture with respect to the placement body. and an extended state in which the length in the conveying direction is extended. The extension body is further provided with an extension body engaging part that engages with the mounting body, and the mounting body is provided at a position facing the extension body engaging part when in the retracted state. a mounting body engaging portion provided to engage with the extension body engaging portion; A base that protrudes from the surface and is slanted so that the amount of protrusion from the mounting-facing surface increases as it moves away from the storage area, which is the area where the extension body in the stored state overlaps on the mounting-facing surface toward the root direction side. A mounting rib having a side inclined portion is further provided.

Further, in the image forming apparatus of the present invention, the main body conveys the medium to form an image, and the medium is conveyed in a base direction approaching the main body along a conveyance path connected to the main body or in a leading end direction away from the main body. At least a part of an extended facing surface of the mounting body is opposed to the mounting facing surface of the mounting body, and the position and attitude of the mounting body are changed to change the position and attitude of the mounting body to the transport path. an extension body that transitions between a retracted state in which the length in the conveying direction is shortened and an unfolded state in which the length in the conveying direction is extended; The extension body is further provided with an extension body engaging part that engages with the mounting body, and the mounting body is engaged with the extension body when in the retracted state. A mounting body engaging portion provided at a position facing the joining portion and engaged with the extension body engaging portion, and a position facing the extension facing surface when the extension body transitions between the retracted state and the expanded state. and protrudes from the mounting facing surface and protrudes from the mounting facing surface as it moves away from the storage area, which is an area where the extension body in the stored state on the mounting facing surface overlaps in the root direction side and a mounting rib having a base-side inclined portion that is inclined so as to increase the width.

According to the present invention, since the extension body engaging portion is engaged with the mounting body engaging portion when the extension body is in the retracted state, the extension body can be engaged even when the front end side of the mounting body faces downward. It can be kept in storage. On the other hand, according to the present invention, when the extension body is shifted from the stored state to the unfolded state, the extension body is caused to ride on the mounting rib while the extension facing surface faces the mounting facing surface. The body engaging portion can be pulled away from the mounting body engaging portion to easily release the engagement.

According to the present invention, it is possible to realize a medium placement device and an image forming apparatus that can maintain a good storage state and realize good operability.

1 is a schematic perspective view showing an external configuration of an image forming apparatus; FIG. FIG. 11 is a schematic diagram showing storage and deployment of the rear tray section; 4 is a schematic perspective view showing the configuration of a rear tray section; FIG. It is a schematic perspective view showing a configuration of a tray. 4 is a schematic diagram showing the configuration of a tray; FIG. It is a schematic perspective view which shows the structure of an engagement hole. 4 is a schematic perspective view showing the configuration of the stacker; FIG. 4 is a schematic diagram showing the configuration of a stacker; FIG. FIG. 4 is a schematic perspective view showing the configuration of an engaging projection; 4A and 4B are schematic diagrams showing a stowed state and an unfolded state of the stacker; FIG. FIG. 5 is a schematic diagram showing transition of stackers to trays; FIG. 5 is a schematic diagram showing the posture of the tray and stacker in the stored state; It is a schematic diagram which shows engagement of an engaging protrusion and an engaging hole. It is a schematic diagram which shows engagement of an engaging protrusion and an engaging hole. FIG. 5 is a schematic diagram showing displacement of the stacker in the stacking direction by tray ribs.

EMBODIMENT OF THE INVENTION Hereinafter, the form (it is mentioned as embodiment below) for implementing invention is demonstrated using drawing.

[1. Configuration of Image Forming Apparatus]
As shown in schematic perspective views in FIGS. 1A and 1B, an image forming apparatus 1 according to the present embodiment is configured in a rectangular parallelepiped shape as a whole. This image forming apparatus 1 is also called a printer, and forms (that is, prints) an image on paper using toner. For convenience of explanation, the front side of the image forming apparatus 1 is assumed to be the front side of the image forming apparatus 1, and the front-back direction, the up-down direction, and the left-right direction when the user faces the front side are defined.

In the image forming apparatus 1, a transport path for transporting paper is formed inside a housing 2. A transport unit that transports paper along the transport path and a toner image that forms a toner image on the paper using toner. An image forming unit for transferring, a fixing unit for fixing the toner image on paper, and the like (none of which are shown) are incorporated.

The image forming apparatus 1 transfers and fixes a toner image on the upper surface of the paper while conveying the paper from the front side to the rear side inside the housing 2, and then moves the paper near the rear end inside the apparatus. Convey upwards. After that, the image forming apparatus 1 directs the sheet on which the image is formed (that is, the image is printed) from the discharge port 3 provided on the rear side of the upper surface so that the surface with the image printed thereon faces downward and the back surface faces upward. , that is, in a face-down state, and placed on the top tray 4 formed on the upper surface of the housing 2 .

When continuously printing a plurality of papers in the top tray 4, the image forming apparatus 1 stacks the later printed papers on the upper side of other papers which have already been printed and whose back surface is turned upward. For this reason, in the image forming apparatus 1, the top tray 4 is mainly used when an image is printed on only one sheet of paper, or when a document or the like over a plurality of pages is printed in page order.

Further, as shown in FIG. 1B, the image forming apparatus 1 is formed with a rectangular rear opening 2RH in the upper portion of the rear side surface 2R of the housing 2 . Further, in the image forming apparatus 1, a rear tray section 7 is incorporated in the rear opening 2RH. 2A, 2B, 2C, and 2D, the rear tray portion 7 is attached to the housing 2 so as to close the rear opening portion 2RH. The state is changed while changing the shape and posture between the stored state (Fig. 2 (A)) stored in the rear side 2R and the expanded state (Fig. 2 (D)) pulled out to the rear side of the rear side surface 2R. Make a transition step by step (details will be described later). Incidentally, the rear tray section 7 transitions to the retracted state or the unfolded state by the user's manual operation.

In addition, the rear tray section 7 forms part of a transport path formed inside the apparatus in the accommodated state. For this reason, if the rear tray section 7 is in the stored state, the image forming apparatus 1 uses the rear tray section 7 to convey the sheet on which the toner image is fixed upward as described above. (Fig. 1(A)) is ejected face down.

On the other hand, if the rear tray section 7 is in the unfolded state, the image forming apparatus 1 feeds the sheet on which the toner image is fixed backward from the middle of the conveying path leading to the discharge port 3 and discharges it from the rear opening 2RH. and placed on the rear tray section 7 . At this time, the paper is in a so-called face-up state, in which the surface on which the image is printed faces upward. Therefore, in the image forming apparatus 1, the rear tray section 7 is used when a document or the like having a plurality of pages is printed in the reverse order of the pages.

[2. Configuration of Rear Tray Section]
Next, the configuration of the rear tray section 7 will be described. The rear tray section 7 as a medium transport device is roughly divided into a face-up cover 11, a tray 12, and a stacker 13, as shown in a perspective view of an unfolded state in FIG. The face-up cover 11, the tray 12, and the stacker 13 are all molded parts by injection molding using a predetermined resin material. Therefore, the face-up cover 11, the tray 12, and the stacker 13 all have sufficient rigidity and flexibility, and are elastically deformed when a relatively large external force is applied, releasing the external force. and returns to its original shape.

For convenience of explanation, the configuration of each part will be explained below based on the attitudes of the face-up cover 11, the tray 12 and the stacker 13 in the unfolded state (FIGS. 2D and 3). In the following description, the upper surface of each of the face-up cover 11, the tray 12, and the stacker 13, on which sheets are to be placed, is called a placement surface. Furthermore, hereinafter, the direction toward the housing 2 on the mounting surface, that is, the direction diagonally forward and downward will be referred to as the root direction, and the opposite direction will be referred to as the tip direction. In the rear tray section 7, in the unfolded state (FIG. 2(D)), the root direction is diagonally forward and downward, and the tip direction is diagonally upward and rearward.

Further, hereinafter, the direction toward either the root direction or the tip direction along the mounting surface is also called the conveying direction, and the left-right direction perpendicular to the conveying direction is also called the width direction. Furthermore, hereinafter, the right direction is also referred to as the first width direction, and the left direction is also referred to as the second width direction. In addition to this, hereinafter, the direction along the normal line of the placement surface (that is, the imaginary straight line connecting the front upper side and the rear lower side) and the direction in which a plurality of ejected sheets are stacked will be referred to as the stacking direction. and the opposite side is called the anti-agglomeration direction. In the rear tray section 7, in the unfolded state (FIG. 2(D)), the stacking direction is the obliquely upward front direction, and the anti-stacking direction is the obliquely downward rearward direction.

[2-1. Configuration of face-up cover]
The face-up cover 11 (FIG. 3) has a flat rectangular parallelepiped shape or a thin plate shape as a whole, is long in the left-right direction, relatively short in the transport direction, and has a length (that is, thickness) in the stacking direction. Sufficiently short (ie thin).

The face-up cover 11 is constructed around a body portion 20 . The main body 20 is formed in the shape of a rectangular parallelepiped or a thin plate that is long in the left-right direction, short in the conveying direction, and thin in the stacking direction. The length of the main body 20 along the transport direction is slightly shorter than the length of the rear opening 2RH (FIG. 1B) in the vertical direction. The length of the body portion 20 in the left-right direction is slightly shorter than the length of the rear opening portion 2RH in the left-right direction.

The surface of the body portion 20 on the anti-stacking direction side is formed substantially flat. Therefore, the face-up cover 11 closes the rear opening 2RH and forms a substantially uniform plane that continues to the rear side surface 2R of the housing 2 in the stored state (FIGS. 1(B) and 2(A)). Therefore, the rear side of the image forming apparatus 1 is neatly shaped.

On the other hand, on the stacking direction side of the main body 20, a plurality of ribs along the conveying direction are erected at predetermined intervals in the left-right direction. In the unfolded state, the face-up cover 11 advances the discharged paper along the conveying direction while contacting the ribs. As a result, the face-up cover 11 minimizes the area of the portion that contacts and slides on the conveyed paper, reduces sliding resistance, and enables smooth progress. In addition, a notch portion 20C that is locally notched toward the root direction is formed in a range of about 1/5 to 1/6 of the center in the left-right direction at the tip end of the body portion 20. .

A left side plate 21L and a right side plate 21R are erected in the stacking direction at both left and right ends of the body portion 20, respectively. A rotating shaft 22 is erected in the left direction in the vicinity of the end on the root side of the left side surface of the left side plate 21L. The rotating shaft 22 is configured in a small columnar shape with a central axis along the left-right direction. The right side plate 21R and the left side plate 21L are substantially bilaterally symmetrical, and a rotation shaft 22 is erected rightward.

On the other hand, housing-side shaft holes (not shown) are provided in the vicinity of the lower ends of the left and right inner surfaces of the rear opening 2RH of the housing 2 (FIG. 1B). This housing-side shaft hole is a round hole with a central axis along the left-right direction, and its diameter is slightly larger than the diameter of the rotating shaft 22 .

The face-up cover 11 can be rotated around the rotation shafts 22 by inserting the rotation shafts 22 into the housing-side shaft holes on the left and right sides, respectively, and can be moved in the retracted state (FIG. 2A) and the expanded state (FIG. 2A). 2(B)), it can be rotated with respect to the housing 2 . Incidentally, the face-up cover 11, in the housed state (FIG. 2(A)), engages a predetermined engaging portion with a predetermined engaged portion (none of which is shown) provided on the housing 2. , so that it can be kept in a stowed state.

Further, the housing 2 limits the rotation range of the face-up cover 11 by a rotation restricting portion (not shown). When the face-up cover 11 is in the unfolded state (FIG. 2(B)) in which it is rotated most rearward from the stored state (FIG. 2(A)), a predetermined portion of the face-up cover 11 is rotated by the housing 2. It abuts on a limiting part (not shown). The face-up cover 11 can maintain this unfolded state by the action of gravity.

Further, the face-up cover 11 is provided with tip-side shaft holes 23 penetrating in the left-right direction near the tip-side ends of the left side plate 21L and the right side plate 21R. Each tip-end-side shaft hole 23 is a round hole with the center axis along the left-right direction.

[2-2. Tray configuration]
Next, the configuration of the tray 12 will be described. The tray 12 as a mounting body is configured around a tray main body 30 as shown in a perspective view in FIG. 4 and a plan view in FIG. The tray main body 30 is formed in the shape of a rectangular parallelepiped or a thin plate that is long in the left-right direction, short in the conveying direction, and thin in the stacking direction. The length of the tray body 30 in the left-right direction is slightly shorter than the length of the face-up cover 11 in the left-right direction. The length of the tray body 30 along the transport direction is shorter than the length of the face-up cover 11 along the transport direction.

A tray-facing surface 30A (hereinafter also referred to as a loading-facing surface), which is a surface of the tray main body 30 on the stacking direction side, is formed in a substantially flat planar shape as a whole. On the other hand, on the counter-stacking direction side of the tray main body 30, a plurality of ribs extending along the conveying direction are erected toward the counter-stacking direction. The edge of the rib on the anti-stacking direction side is concavely curved toward the anti-stacking direction, and in the stored state (FIG. 2A), it becomes the rear portion of the paper transport path.

A left side plate 31L and a right side plate 31R are erected toward the stacking direction at the base side of the left end and the right end of the tray main body 30, respectively. The left side plate 31L has a wedge shape such that the length in the stacking direction becomes larger (longer) as it proceeds toward the base when viewed from the left-right direction. Further, a rotating shaft 32 is erected toward the left in the vicinity of the root side end of the left side surface of the left side plate 31L. As with the rotating shaft 22 of the face-up cover 11, the rotating shaft 32 is formed in a small columnar shape with a central axis along the left-right direction. The diameter of the rotating shaft 32 is slightly shorter (smaller) than the diameter of the tip-side shaft hole 23 in the face-up cover 11 .

The tray 12 rotates with respect to the face-up cover 11 with the rotation shafts 32 as the center of rotation by inserting the left and right rotation shafts 32 into the tip end side shaft holes 23 of the face-up cover 11 . be able to. That is, the tray 12 can be accommodated in such a manner that the tip side faces the root side of the face-up cover 11 as shown in FIG. As shown, it is possible to transition from the retracted state to the unfolded state in which the mounting surface is turned about 180 degrees to face the stacking direction.

The tray 12 is provided with a tray boss 33 , a flange 34 , a tray groove 35 , an engagement hole 36 , two tray ribs 37 , a root side plate 38 and a regulation plate 39 . A tray boss 33 as a mounting protrusion is formed from the center in the left-right direction of a tray-facing surface 30A (hereinafter also referred to as a mounting-facing surface), which is a surface (that is, a mounting surface) of the tray body 30 on the stacking direction side. It is slightly to the left and is provided substantially in the center with respect to the conveying direction. The tray boss 33 is formed in a cylindrical shape with a center axis along the stacking direction, and protrudes from the tray-facing surface 30A in the stacking direction.

A flange 34 as an opposing maintenance portion is provided at the end of the stacking direction side of the tray boss 33 . The flange 34 is formed in the shape of a thin disc with its central axis aligned with the stacking direction, and its central axis coincides with the central axis of the tray boss 33 . The diameter of the flange 34 is sufficiently larger than the diameter of the tray boss 33 . A flange regulating surface 34S, which is the surface of the flange 34 on the opposite side of the stacking direction, is a plane substantially parallel to the tray facing surface 30A.

The tray groove portion 35 as the mounting groove portion is provided on the right side of the center of the tray facing surface 30A in the left-right direction and near the root direction with respect to the transport direction. The tray groove portion 35 has a curved shape along the virtual tray groove center line 35X shown in FIG. 5, and is formed with substantially constant width and depth. On the tray facing surface 30A, the tray groove center line 35X inclines from the tray groove storage point 35XA, which is the right end as a whole, toward the root as it progresses toward the center, and eventually reaches the center end. A curve is drawn to reach the tray groove development point 35XB.

Specifically, the tray groove center line 35X starts from a tray groove storage point 35XA slightly separated from the root side end in the vicinity of the right end toward the distal direction, proceeds substantially leftward, and soon curves toward the root. , advance while tilting to the left and right direction. After that, the tray groove center line 35X curves so that the traveling direction gradually turns leftward near the center of the tray facing surface 30A in the left-right direction, and then turns substantially leftward again near the end point. In addition, a narrowed portion 35S with a locally narrowed groove width is formed at a portion of the tray groove portion 35 slightly shifted to the right side from the central end portion. For convenience of explanation, the tray groove accommodation point 35XA and the tray groove development point 35XB are hereinafter also referred to as the loading groove storage point and the loading groove development point, respectively.

The engagement hole 36 as the mounting body engagement portion is located on the left side of the tray boss 33 and is recessed in the anti-stacking direction from the tray facing surface 30A. As shown in the enlarged perspective view of FIG. 6, the engaging hole 36 is a rectangular parallelepiped space as a whole, and the surface in the anti-accumulation direction, that is, the bottom surface is planar and substantially parallel to the tray facing surface 30A. It has become.

Approximately half of the right side surface of the engaging hole 36 in the distal direction is a hole engaging portion 41 formed of a flat surface with the normal directed to the root direction. Approximately the left half of the side surface of the engaging hole 36 in the distal direction is a hole inclined portion 42 which is an inclined surface that is inclined so as to approach the tray facing surface 30A as it advances in the distal direction. That is, the hole inclined portion 42 is adjacent to the left side of the hole engaging portion 41 and is provided on the tip side of the hole engaging portion 41 .

Tray ribs 37 serving as mounting ribs are provided at two positions slightly away from the left end and at positions slightly away from the right end of the approximately half range on the tip end side of the tray facing surface 30A. The tray rib 37 protrudes in the stacking direction from the tray facing surface 30A, and is formed in a thin plate shape that is long in the conveying direction, short in the stacking direction, and extremely short in the left-right direction. The length (height) of the tray rib 37 from the tray facing surface 30A to the most protruded portion in the stacking direction is shorter (lower) than the length (height) of the tray boss 33 .

The tray rib 37 is formed with a root-side inclined portion 37A and a tip-side inclined portion 37B near the ends on the root side and the tip end, respectively. The length (height) of the root-side inclined portion 37A from the tray-facing surface 30A to the stacking-direction-side end gradually increases (heights) from the root to the tip. Further, the length (height) from the tray facing surface 30A to the stacking direction end of the leading end side inclined portion 37B gradually increases (heights) from the leading end side toward the root direction.

The base side plate 38 is erected in the stacking direction over the entire range from the left end to the right end of the end portion on the base side of the tray body portion 30 . The base side plate 38 is formed in a plate shape that is sufficiently shorter in the stacking direction than in the lateral direction and is thin in the conveying direction. The base side plate 38 is longer (higher) than the flange 34 attached to the tray boss 33, and has a distance from the tray facing surface 30A to the end in the stacking direction, that is, the height. It is shorter than the distance to each rotating shaft 32 provided.

The restricting plate 39 is erected toward the distal end in a range of about 1/5 to 1/6 near the center in the left-right direction of the upper end of the base side plate 38 . The regulating plate 39 has a flat rectangular parallelepiped shape or a plate shape whose length in the transport direction is sufficiently shorter than its length in the left-right direction and whose length in the stacking direction is even shorter. That is, the restricting plate 39 faces the tray facing surface 30A of the tray main body 30 with the restricting surface 39S, which is the side surface on the side opposite to the stacking direction. Incidentally, the length of the regulation surface 39S in the left-right direction is slightly shorter than the length of the notch 20C (FIG. 3) formed in the body portion 20 of the face-up cover 11 in the left-right direction.

[2-3. Configuration of stacker]
Next, the configuration of the stacker 13 (FIG. 2) will be described. The stacker 13 as an extension body is configured around a stacker main body 50 as shown in perspective views in FIGS. 7A and 7B and in plan views in FIGS. 8A and 8B. there is The stacker main body 50, in the unfolded state (FIGS. 2D and 3), is long in the conveying direction, short in the left-right direction, and thin and flat along the stacking direction. . In other words, the stacker 13 is configured in a rectangular shape with long sides in the transport direction and short sides in the horizontal direction when viewed from the stacking direction.

A stacker placement surface 50A, which is the surface of the stacker main body 50 on the stacking direction side (that is, the stacking surface), and a stacker-facing surface 50B, which is the surface on the opposite stacking direction side and faces the tray 12 (hereinafter referred to as an extended opposing surface). ) are formed in a flat shape as a whole. Further, the left root portion 50R, which is near the root side and left vertex of the stacker main body portion 50, is rounded in an arc shape centering on the imaginary center point 50C when viewed from the stacking direction side or the anti-stacking direction side. . The radius of this arc is half the length of the stacker 13 along the left-right direction, that is, the length of the short side. That is, the center point 50C is positioned at the center of the stacker 13 in the left-right direction.

The stacker main body 50 has a length in the stacking direction, that is, a distance from the stacker mounting surface 50A to the stacker facing surface 50B, and the length corresponding to the thickness is the tray facing surface 30A of the tray 12 (FIG. 4). to the flange restricting surface 34</b>S of the flange 34 .

The stacker 13 is provided with a stacker boss 51 , a stacker groove portion 52 , a peripheral side plate 53 , a stacker central rib 54 , a grip portion 55 , an engaging projection 56 and a slit 57 in a stacker body portion 50 .

The stacker boss 51 as an extended protrusion extends from the end of the stacker-facing surface 50B (FIGS. 7B and 8B) in the left-right direction and on the base side in the conveying direction toward the tip. It is located at some distance. Incidentally, the stacker boss 51 is positioned closer to the root than the imaginary center point 50C, which is the center of the left root portion 50R. The stacker boss 51 is formed in a cylindrical shape with a central axis along the anti-stacking direction, and protrudes in the anti-stacking direction from the stacker-facing surface 50B. The diameter of the stacker boss 51 is slightly shorter than the groove width of the tray groove portion 35 (FIG. 5) and slightly longer than the groove width of the constricted portion 35S in the tray groove portion 35. As shown in FIG.

The stacker groove portion 52 as an extended groove portion extends in the stacking direction in a range of about 3/5 from the end on the base side in the transport direction of the stacker main body 50, and in a range near the center in the left-right direction, excluding the vicinities of both ends. It is formed as an elongated hole or groove penetrating through.

As shown in FIG. 8A, the stacker groove portion 52 is formed along a virtual stacker groove center line 52X. The stacker groove center line 52X passes through both the stacker groove storage point 52XA positioned relatively right on the tip side and the stacker groove expansion point 52XB positioned relatively left on the root side, and is generally rightward. It has an arcuate shape with a virtual center point, that is, it has a curvilinear shape that protrudes leftward. For convenience of explanation, the stacker groove storage point 52XA and the stacker groove deployment point 52XB are hereinafter also referred to as an extended groove storage point and an extended groove deployment point, respectively.

Also, the stacker groove portion 52 has a substantially constant groove width along the stacker groove center line 52X, but the flange passage portion in which the groove width is locally expanded toward the root side of the stacker groove portion development point 52XB. 52A is formed. The flange passing portion 52A has a shape similar to a circle, and its diameter is slightly larger than the diameter of the flange 34 of the tray 12 (FIGS. 4 and 5).

The peripheral side plate 53 is provided on the outer peripheral portion of the stacker main body 50 on the side of the stacker mounting surface 50A, excluding one side along the edge on the tip side, that is, on the left side, the base side, the right side, and the left base. It is provided over the arcuate portion of the portion 50R. The peripheral side plate 53 is a plate-shaped member erected from the stacker mounting surface 50A toward the stacking direction, and has a length (that is, thickness) along the left-right direction or the transport direction and a stacking distance from the stacker mounting surface 50A. The length (that is, height) to the end on the direction side is substantially constant.

The peripheral side plate 53 has a length (that is, height) from the stacker mounting surface 50A to the end in the stacking direction that is equal to the length (that is, height or thickness) of the flange 34 in the stacking direction of the tray 12 (FIG. 4). ) is sufficiently larger than Further, in the stacker 13, the distance from the stacker facing surface 50B to the stacking direction vertex of the peripheral side plate 53, that is, the apparent thickness of the stacker 13 is the distance from the tray facing surface 30A of the tray 12 to the regulating surface 39S of the regulating plate 39. It is slightly shorter than the distance.

The stacker center rib 54 is provided substantially in the center in the left-right direction, and is erected from the stacker mounting surface 50A toward the stacking direction. The stacker central rib 54 is formed in the shape of a rectangular parallelepiped or a thin plate that is long in the transport direction, short in the stacking direction, and thin in the left-right direction. Also, the stacker center rib 54 has a length (that is, height) from the stacker mounting surface 50A to the end in the stacking direction, which is the same as that of the peripheral side plate 53 .

Further, the stacker central rib 54 is connected to the peripheral side plate 53 on the base side and is connected to the gripping portion 55 described later on the tip side, but is omitted in the portion intersecting the stacker groove portion 52 and in the vicinity thereof, and the base side and is divided into two on the tip side.

The gripping portion 55 is provided substantially in the center of the stacker mounting surface 50A in the left-right direction and near the end in the leading end direction, that is, at a position adjacent to the stacker center rib 54 in the leading end direction. The gripping portion 55 is formed in the shape of a rectangular parallelepiped or a thin plate that is long in the conveying direction, short in the stacking direction, and even shorter in the left-right direction. However, the length of the grip portion 55 along the stacking direction and the length of the left-right direction are both longer than the length of the stacker central rib 54 along the stacking direction and the length of the left-right direction. In addition, the base side portion of the grip portion 55 is inclined so that the length (that is, the height) in the stacking direction from the stacker placement surface 50A increases (longer) as it proceeds from the base side end to the tip side. are doing. Furthermore, the end portion of the grip portion 55 in the distal direction is reinforced by being extended in the left-right direction.

The engaging protrusion 56 as an extension body engaging portion is located on the right side of the stacker facing surface 50B in the left-right direction and is about 1/3 of the total length from the end on the leading end side in the conveying direction. It is provided at a location slightly away from the root side end of 52 in the root direction. The engagement protrusion 56 protrudes from the stacker-facing surface 50B in the anti-stacking direction. The length from the stacker-facing surface 50B of the engaging projection 56 to the most projecting portion in the anti-stacking direction, that is, the height is determined from the tray-facing surface 30A of the engaging hole 36 in the tray 12 (FIGS. 4 and 5). is shorter than the depth of

As shown in an enlarged perspective view of FIG. 9, the engaging protrusions 56 have a shape similar to a so-called gabled roof or hipped roof as a whole, and a plurality of portions on the anti-stacking side of the small rectangular parallelepiped are attached to the stacker. It has a shape obtained by obliquely cutting off the facing surface 50B. Specifically, the engaging projection 56 has a projection engaging portion 61 formed of a flat surface whose normal is directed to the right in about half of the root side of the right side surface of the rectangular parallelepiped. The end portion of the protrusion engaging portion 61 on the opposite side of the stacking direction is subjected to a so-called rounding process, and is formed in an arc shape when viewed from the root side or the tip side.

The engaging projection 56 is formed with three inclined portions, namely, a right inclined portion 62 , a tip inclined portion 63 and a left inclined portion 64 . Approximately half of the tip side of the right side surface of the above-described rectangular parallelepiped projecting right inclined portion 62 is an inclined surface that is inclined so as to advance in the anti-stacking direction from the stacker facing surface 50B as it advances leftward. The projecting tip inclined portion 63 is an inclined surface in which the tip side of the rectangular parallelepiped described above is inclined so as to advance in the anti-stacking direction from the stacker facing surface 50B as it advances in the root direction. The projection left inclined portion 64 is an inclined surface in which the left side surface of the rectangular parallelepiped described above is inclined so as to advance in the anti-stacking direction from the stacker facing surface 50B as it advances rightward. For convenience of explanation, the projection right inclined portion 62 and the projection left inclined portion 64 are hereinafter also referred to as a projection width first inclined portion and a projection width second inclined portion, respectively.

The slits 57 are provided on the base direction side and the tip direction side of the engaging projection 56 in the stacker main body 50 and at locations close to the engaging projection 56 . In other words, the engaging projections 56 are arranged between the slits 57 formed at two locations apart along the stacking direction. Each slit 57 is formed as an elongated long hole or groove along the left-right direction penetrating in the stacking direction. Each of the slits 57 is formed from a position slightly away from the right side of the stacker central rib 54 to a position slightly away from the left side of the peripheral side plate 53 positioned at the right end of the stacker main body 50 .

[2-4. Transition of Stacker to Tray]
Next, how the stacker 13 rotates and moves with respect to the tray 12 in the rear tray section 7 and transitions between the stored state and the unfolded state will be described. In the rear tray section 7, after the face-up cover 11, the tray 12 and the stacker 13 are manufactured by a construction method such as injection molding, the stacker 13 is attached to the tray 12 in the assembly process, and then the tray 12 is attached to the face. It is attached to the up cover 11 .

In the step of attaching the stacker 13 to the tray 12, the front end of the stacker 13 is directed to the right side of the tray 12, and the stacker 13 is positioned on the stacking direction side of the tray 12 and the flange of the stacker groove portion 52. The passage portion 52A is positioned so as to match the flange 34. As shown in FIG.

Then, the stacker 13 is moved in the anti-stacking direction to insert the flange 34 into the flange passing portion 52A so that the flange 34 is positioned on the stacking direction side of the stacker mounting surface 50A, and the flange passing portion 52A is moved. , the stacker-facing surface 50B is brought into contact with the tray-facing surface 30A. At this time, the stacker boss 51 abuts the tray facing surface 30A of the stacker 13, so that the stacker main body 50 is elastically deformed, and the stacker facing surface 50B near the stacker boss 51 is lifted from the tray facing surface 30A.

In this state, the stacker 13 is moved and rotated to the right or to the base with respect to the tray 12 to move the stacker boss 51 into the tray groove portion 35 while moving the tray boss 33 toward the front end side within the stacker groove portion 52 . let in. As a result, the flange 34 can maintain a facing state in which the stacker facing surface 50B faces the tray facing surface 30A.

Further, the stacker 13 continues to move and rotate in the rightward direction or in the base direction with respect to the tray 12, thereby causing the tray boss 33 to reach the stacker groove storage point 52XA on the extreme front end side in the stacker groove 52, and the stacker boss 51 reaches the most proximal tray groove storage point 35XA in the tray groove 35. As shown in FIG.

Thus, the stacker 13 is housed with its root portion directed to the right and its tip portion directed to the left, and stacked on the root side area of the tray 12 (FIGS. 2C and 10A). At this time, the stacker 13 positions the left end (FIG. 8) slightly toward the tip side of the base side plate 38 of the tray 12, and the left side and the right side (that is, the long side) of the tray 12 are substantially the sides of the tray 12 on the base side. parallel.

Here, an area where the stacker 13 in the stored state overlaps with the tray 12 is defined as a stacker storage area RA. As shown in FIG. 5, in the tray 12, the tray boss 33 and the flange 34, the majority of the tray groove portion 35 except for the vicinity of the left end, the engagement hole 36, the portion of each tray rib 37 on the root direction side, and the restricting plate 39. Of these, a part on the leading end side is located within the range of the stacker storage area RA.

In the tray 12 in which the stacker 13 is assembled in this way, the left and right rotation shafts 22 are inserted through the left and right front end side shaft holes 23 ( FIG. 3 ) of the face-up cover 11 . This completes the assembly process of the rear tray section 7 (FIG. 3).

In the assembled rear tray section 7, the stacker facing surface 50B of the stacker 13 faces the tray facing surface 30A of the tray 12 by the flange 34 of the tray 12, and the contact state is maintained. In the rear tray section 7 , the stacker 13 can be moved and rotated with respect to the tray 12 while moving the tray boss 33 within the stacker groove 52 and moving the stacker boss 51 within the tray groove 35 .

For example, as shown in FIGS. 2(C) and 10(A), the rear tray section 7 is arranged such that the engaging protrusions 56 of the stacker 13 are engaged with the tray 12 when the stacker 13 is accommodated in the tray 12 . The mating hole 36 is engaged with the stacker 13 to maintain the stacker 13 in the retracted state with respect to the tray 12 (details will be described later). In this state, when the gripping portion 55 of the stacker 13 is gripped by the user and an external force is applied in the leftward or distal direction, the rear tray portion 7 releases the engagement between the engaging projection 56 and the engaging hole 36, The stacker 13 starts moving and rotating with respect to the tray 12 .

Specifically, in the rear tray section 7, as shown in FIG. 11, the stacker 13 moves and rotates while rotating the tip end portion toward the tip end and moving the base portion leftward. go. At this time, in the rear tray portion 7, the stacker boss 51 moves within the tray groove portion 35 from the tray groove storage point 35XA along the tray groove center line 35X to the tray groove development point 35XB. In the rear tray section 7, the tray boss 33 moves within the stacker groove 52 from the stacker groove storage point 52XA along the stacker groove center line 52X to the stacker groove development point 52XB. However, in this case, the tray boss 33 of the tray 12 does not actually move, and the stacker 13 and the stacker groove portion 52 apparently move and rotate, causing the tray boss 33 to relatively move within the stacker groove portion 52 . are doing.

In the rear tray section 7, the stacker boss 51 comes into contact with the constricted portion 35S of the tray groove section 35 just before the stacker 13 rotates about 90 degrees from the stored state, and the rotation stops or decelerates. In the rear tray section 7, when a larger force is applied to the gripping section 55 of the stacker 13, the stacker boss 51 temporarily elastically deforms the tray 12 to expand the groove width of the constricted section 35S. 35S to reach the stacker groove development point 52XB. As a result, the stacker 13 is in the unfolded state shown in FIG. 10(B).

At this time, the stacker 13 assumes a posture in which the base portion is oriented in the base direction and the tip portion is oriented in the tip direction. In addition, the stacker 13 positions the end on the base side between the tray facing surface 30A and the regulation surface 39S of the regulation plate 39 in the vicinity of the center of the tray 12 in the left-right direction, and further positions the end on the tip side on the tray 12. It is located farther in the distal direction than the distal end of the . As a result, the rear tray section 7 can greatly extend the total length in the transport direction compared to the stored state.

The image forming apparatus 1 (FIG. 1) discharges the sheet on which an image is formed rearward from the rear opening 2RH and stacks the sheet with the rear tray section 7 in the unfolded state (FIGS. 2D, 3, etc.). Move backward along the surface. At this time, in the rear tray section 7, a plurality of ribs formed on the face-up cover 11, a tray rib 37 formed on the tray 12, a stacker central rib 54 formed on the stacker 13, a peripheral side plate 53, and the like form the paper and the rear tray. The contact resistance with the portion 7 can be minimized to allow smooth progress.

[2-5. Storage state and transition of stacker]
Next, a storage state in which the stacker 13 is stored with respect to the tray 12 in the rear tray section 7 will be described. FIG. 12 shows a state in which the rear tray section 7 is housed in the housing 2 of the image forming apparatus 1 (FIGS. 1B and 2A). 12 and the stacker 13 are stored.

In FIG. 12, the tray 12 has its leading end facing downward. For this reason, as can be seen from FIG. 11, in the rear tray section 7, the stacker 13 in the housed state is subjected to an external force such as to move and rotate the front end side downward due to gravity, that is, to transition from the housed state to the unfolded state. The force to try will act.

Here, FIG. 13A shows a cross-sectional view of the engaging projection 56 cut along the stacker facing surface 50B, and FIG. 13B shows a partially enlarged view thereof. 14A and 14B respectively show the A1-A2 cross-sectional view and the B1-B2 cross-sectional view in FIG. 13B. 13 and 14, the projection engaging portion 61 of the engaging projection 56 of the stacker 13 engages the hole engaging portion 41 of the engaging hole 36 of the tray 12. , the stacker 13 is prevented from moving and rotating the leading end side downward, that is, from attempting to transition to the unfolded state.

In the rear tray section 7, the flange 34 maintains the stacker-facing surface 50B of the stacker 13 facing the tray-facing surface 30A of the tray 12 in contact with or very close to the tray-facing surface 30A. As a result, in the rear tray section 7, the engagement between the projection engaging portion 61 of the engaging projection 56 and the hole engaging portion 41 of the engaging hole 36 is maintained.

By the way, as shown in FIG. 5, a portion of the tray rib 37 on the root side, that is, a portion of the root side inclined portion 37A on the root side of the tray 12 is positioned within the stacker storage area RA. For this reason, in the rear tray section 7, as shown in FIG. 15A which is a sectional view taken along the line C1-C2 in FIG. The facing surface 50B is slightly separated from the tray facing surface 30A. Incidentally, in the C1-C2 section at this time, the distance by which the stacker-facing surface 50B is separated from the tray-facing surface 30A is the distance between the stacking-direction-side end portions of the tray ribs 37 and the contacting portion of the stacker-facing surface 50B. , the distance (height) from the tray facing surface 30A.

In the rear tray section 7 , the central portion of the stacker-facing surface 50</b>B of the stacker 13 abuts or is extremely close to the tray-facing surface 30</b>A of the tray 12 by the flange 34 , as described above. For this reason, the stacker 13 is elastically deformed so as to lift the tip side in the longitudinal direction in the stacking direction.

By the way, in the rear tray section 7, as shown in FIG. 11, when the user applies a leftward or frontward force to the grip section 55 of the stacker 13, the stacker 13 transitions from the stored state to the unfolded state. start. At this time, the stacker 13 is mainly moved leftward, and is gradually turned so that the leading end side faces the leading end direction. Accordingly, in the rear tray section 7, as shown in FIG. 13C corresponding to FIG. , the projection engaging portion 61 is located in the root direction of the hole inclined portion 42 . As a result, the engagement between the engagement protrusion 56 and the engagement hole 36 is released in the rear tray section 7 .

Further, in the rear tray portion 7, as shown in FIG. 15A, a root-side inclined portion 37A is formed on the root side of the tray rib 37 of the tray 12. As shown in FIG. For this reason, in the rear tray section 7, when the stacker 13 is in the housed state, the end of the stacker facing surface 50B of the stacker 13 located on the front end side comes into contact with the vicinity of the midpoint of the base side inclined portion 37A, which is the stacker. 13 has run over the tray rib 37 .

Here, when the user applies a leftward or distal force to the gripping portion 55 of the stacker 13 in the rear tray portion 7, the stacker 13 moves the portion of contact with the tray rib 37 along the root side inclined portion 37A. Move to the tip side. As a result, in the rear tray section 7, the stacker-facing surface 50B is gradually moved away from the tray-facing surface 30A, and eventually, as shown in FIG. It reaches the tip-side end of the root-side inclined portion 37A.

Here, the tray rib 37 has a distance (protrusion amount) from the tray facing surface 30A at the most protruding portion in the stacking direction from the tray facing surface 30A so as to be anti-stacking from the stacker facing surface 50B of the engaging projection 56 of the stacker 13. It is larger than the distance (protrusion amount) from the stacker-facing surface 50B at the most projecting portion in the direction. At this time, the engaging projection 56 is pulled up toward the stacking direction side of the tray facing surface 30A and exits from the engaging hole 36, and is positioned toward the tip or left of the engaging hole 36. As shown in FIG.

After that, in the rear tray section 7, when the front end side of the stacker 13 advances in the front end direction, the distance between the stacker facing surface 50B and the tray facing surface 30A is maintained substantially, that is, the engaging projection 56 is moved further than the tray facing surface 30A. While being kept floating in the stacking direction, the abutting portion between the stacker-facing surface 50B and the tray rib 37 is moved toward the leading end.

Eventually, in the rear tray section 7, the base side of the stacker 13 reaches the leading end side inclined portion 37B of the tray rib 37, as shown in FIG. 15(C). At this stage, the engaging projection 56 is located in the distal direction from the distal end of the tray facing surface 30A of the tray 12 . In the rear tray section 7, the stacker 13 is further moved and rotated to move the base end of the stacker-facing surface 50B of the stacker 13 along the tip-side inclined portion 37B in the tip direction and the anti-stacking direction.

Eventually, in the rear tray section 7, as shown in FIG. 15(D), when the base end of the stacker-facing surface 50B of the stacker 13 reaches the tip-side end of the tip-side inclined portion 37B, the stacker-facing surface 50B is moved. By contacting the tray facing surface 30A, the elastic deformation of the stacker 13 is eliminated and returned to its natural state. After that, in the rear tray section 7, the stacker 13 is further rotated and moved to the unfolded state (FIG. 10(B)).

Incidentally, in the rear tray section 7, when the unfolded state (FIG. 10B) transitions to the stowed state (FIG. 10A), the series of relationships (FIG. 15) described above between the stacker 13 and the tray ribs 37 are reversed. will be reproduced in the order of

[3. effects, etc.]
In the above configuration, the rear tray section 7 (FIGS. 2 and 3) of the image forming apparatus 1 according to the present embodiment enables the face-up cover 11 to rotate with respect to the rear side surface 2R of the housing 2. A tray 12 is rotatable with respect to 11, and a stacker 13 is moved and rotated with respect to the tray 12.例文帳に追加

In the rear tray section 7, the stacker 13 is moved and rotated with respect to the tray 12 by moving the tray boss 33 along the stacker groove 52 and moving the stacker boss 51 along the tray groove 35 (FIG. 11). In the rear tray section 7, the stacker 13 is moved and rotated while the tray-facing surface 30A of the tray 12 and the stacker-facing surface 50B of the stacker 13 are kept in contact with each other or extremely close to each other by the flange 34. . In addition, in the rear tray section 7, the tray 12 (FIGS. 4 to 6) is provided with the engagement hole 36 and the stacker 13 (FIGS. 7 to 9) is provided with the engagement projection 56. FIG.

Particularly in the rear tray section 7, when the stacker 13, the tray 12 and the face-up cover 11 are both in the stored state (FIGS. 1, 2A and 12), the tray with the stacker 13 in the stored state 12 (FIG. 10(A)) faces substantially downward, and gravity acts on the stacker 13 in the direction of transition to the unfolded state.

In this regard, in the rear tray portion 7, the projection engaging portion 61 of the engaging projection 56 is engaged with the hole engaging portion 41 of the engaging hole 36 (FIGS. 13 and 14), and the flange 34 allows the tray 12 to face the tray. The surface 30A and the stacker-facing surface 50B of the stacker 13 are kept in contact or very close to each other. For this reason, in the rear tray section 7, even if the front end of the tray 12 faces substantially downward, and even if the face-up cover 11 is rotated or otherwise subjected to vibration or impact, the engaging projections 56 and The engagement hole 36 is kept engaged, and the storage state of the stacker 13 can be reliably maintained.

Viewed from another point of view, in the rear tray section 7, the stacker 13 is provided with an engaging protrusion 56 projecting in the anti-stacking direction from the stacker facing surface 50B as an extension body engaging portion provided on the stacker 13, and the stacker engaging portion provided on the tray 12 is provided. An engagement hole 36 recessed in the anti-stacking direction from the tray facing surface 30A is provided as a joining portion. As a result, in the rear tray section 7, there is no need for the mounting body engaging section to protrude from the tray facing surface 30A in the stacking direction, and the possibility that the leading edge of the sheet is caught in the unfolded state (FIG. 10B) can be eliminated.

In addition to this, in the rear tray section 7, the tray 12 (FIG. 5 etc.) is provided with the tray rib 37, and the base side inclined portion 37A and the tip side inclined portion 37B are provided on the base side and the tip side thereof. As a result, in the rear tray section 7, when the stacker 13 is moved and rotated from the stored state (FIG. 10A), the stacker 13 is lifted onto the tray rib 37 to separate the stacker facing surface 50B from the tray facing surface 30A. can be done. Therefore, in the rear tray section 7, the engaging protrusions 56 can be lifted (floated) from the engaging holes 36 in the stacking direction. , the stacker 13 can be smoothly moved and rotated.

In addition, in the tray 12 (FIG. 5), a part of the root side of the tray rib 37 is positioned within the stacker storage area RA. For this reason, in the rear tray section 7, the stacker 13 starts to move and rotate toward the unfolded state so that the end of the stacker-facing surface 50B on the leading end side rides on the base-side inclined portion 37A of the tray rib 37 when the stacker 13 is in the accommodated state. Sometimes, it can be smoothly advanced along the root-side inclined portion 37A.

Looking at this from another point of view, in the rear tray section 7, when the stacker 13 is in the stored state (FIG. 10A), the stacker 13 is urged in the stacking direction by the tray ribs 37 near both ends in the longitudinal direction. On the other hand, it is pressed in the anti-accumulation direction by a flange 34 near the center in the longitudinal direction. Therefore, in the rear tray section 7, the stacker 13 is elastically deformed from the natural state in which the stacker facing surface 50B is aligned with the plane, and the action of the restoring force causes a part of the stacker mounting surface 50A to move to the flange restricting surface 34S of the flange 34. ( FIG. 4 ), and a part of the stacker-facing surface 50 B is brought into contact with the root-side inclined portion 37 A of the tray rib 37 . As a result, in the rear tray section 7, rattling and vibration of the stacker 13 in the stored state with respect to the tray 12 can be suppressed, and noise generation and wear of parts can be prevented.

Further, in the stacker 13, about half of the root side of the right side surface of the engaging protrusion 56 is used as a protrusion engaging portion 61, and a protrusion right inclined portion 62 is provided on the tip side thereof (FIG. 9). Further, in the tray 12, about half of the right side of the side surface of the engaging hole 36 in the tip direction is used as the hole engaging portion 41, and the hole inclined portion 42 is provided on the left side thereof (FIG. 6). Therefore, in the rear tray section 7, the engagement of the engagement projection 56 can be achieved simply by moving the stacker 13 slightly to the right from the storage state (FIG. 10A) in which the engagement projection 56 and the engagement hole 36 are engaged with each other. By moving the joining portion 61 from the root side of the hole engaging portion 41 to the root side of the hole inclined portion 42 (FIGS. 13B and 13C), the engagement can be easily released.

Further, in the stacker 13, a protrusion tip inclined portion 63 is formed on the tip side of the engaging protrusion 56 (FIG. 9). Therefore, in the rear tray section 7, when the stacker 13 is slightly moved to the right from the storage state (FIG. 10A) in which the engaging projection 56 and the engaging hole 36 are engaged, the engaging projection 56 is engaged. The possibility of abutting against the left inner surface of the joint hole 36 and impeding this movement can be eliminated.

In addition to this, in the stacker 13, a projection left inclined portion 64 is formed on the left side of the engaging projection 56 (FIG. 9). In the rear tray section 7, when the stacker 13 is shifted from the unfolded state (FIG. 10B) to the stowed state (FIG. 10A), if the distance by which the stacker-facing surface 50B is lifted by the tray ribs 37 is short, the engaging projections Since a part of 56 is located on the counter stacking direction side of the tray facing surface 30A, it may come into contact with the tray main body 30 . At this time, the rear tray section 7 can gradually move the engaging projection 56 onto the tray facing surface 30A by the projection left inclined portion 64, so that the stacker 13 can be smoothly moved and rotated.

Further, in the stacker 13 (FIGS. 4 and 5), the engaging projection 56 is arranged on the left side of the stacker groove housing point 52XA in the stacker groove 52 and on the right side of the grip portion 55. As shown in FIG. For this reason, in the rear tray portion 7, when the stacker 13 is moved and rotated from the stored state, the engaging projections, which are points of action, are placed between the tray bosses 33, which are fulcrums, and the grip portions 55, which are points of force, in the left-right direction. 56 can be positioned. As a result, in the rear tray section 7, even if the amount of movement of the engaging projections 56 in the stacking direction is small and part of the engaging projections 56 are engaged with the engaging holes 36, the so-called "principle of leverage" is applied. As a result, a force larger than the force applied to the grip portion 55 by the user can be applied to the engaging projection 56, and the engagement with the engaging hole 36 can be easily released.

Furthermore, in the stacker 13 (FIGS. 4 and 5), between the stacker groove storage point 52XA in the stacker groove 52 and the engagement protrusion 56, and the grip portion 55, on the right and left sides in the vicinity of the engagement projection 56, that is, in the left-right direction. and between the engaging projections 56, slits 57 are provided respectively. Therefore, in the stacker 13, the engagement projection 56 and its peripheral portion can be displaced more than the entire stacker body 50 in the stacking direction.

In the rear tray section 7, as described above, when the stacker 13 is moved and rotated from the accommodated state, if the amount of movement of the engaging projections 56 in the stacking direction is small, a portion of the engaging projections 56 may become the engaging holes. 36 may become engaged. However, in the rear tray section 7, even in such a state, when the user applies a sufficient force to the stacker 13 via the grip section 55, the peripheral portion of the engaging projection 56 is locally bent. Then, the projection engaging portion 61 of the engaging projection 56 is made to climb over the hole engaging portion 41 of the engaging hole 36, and the engagement between the two can be easily released.

According to the above configuration, the image forming apparatus 1 according to the present embodiment moves and rotates the stacker 13 with respect to the tray 12 in the rear tray section 7 to transition to the storage state or the unfolded state. In the rear tray section 7 , the engaging protrusions 56 are provided on the stacker 13 and the engaging holes 36 and tray ribs 37 are provided on the tray 12 . Therefore, even if the front end of the tray 12 in which the stacker 13 is accommodated faces downward, the rear tray section 7 engages the engagement protrusion 56 with the engagement hole 36, and the stacker 13 rotates due to gravity. You can prevent it from moving. On the other hand, when the stacker 13 is moved and rotated from the stored state, the rear tray section 7 rides on the tray ribs 37 to release the engagement between the engaging projections 56 and the engaging holes 36 and smoothly transition. be able to.

[4. Other embodiments]
In the above-described embodiment, by locating a portion of the root side of the tray rib 37 in the tray 12 (FIG. 5, etc.) within the stacker storage area RA, when the stacker 13 is stored, the front end side of the stacker facing surface 50B is positioned. A case has been described in which the end portion is run over the root side inclined portion 37A of the tray rib 37 (FIG. 15(A)). However, the present invention is not limited to this. For example, by locating the tray rib 37 outside (front end side) of the stacker housing area RA, the stacker facing surface 50B can be brought into contact with the tray facing surface 30A when the stacker 13 is in the stowed state. good. In addition, the tray ribs 37 on the left and right sides of the tray 12 may have different shapes instead of having the same configuration. Further, the tray rib 37 on the right side of the tray 12 may be omitted and only one rib may be provided, or three or more tray ribs 37 may be provided.

Furthermore, in the above-described embodiment, the stacker 13 is provided with the engaging protrusions 56 as the extension body engaging portions, and the tray 12 is provided with the engaging holes 36 as the mounting body engaging portions, so that the stacker 13 can be accommodated. A case has been described in which the engagement protrusion 56 and the engagement hole 36 are engaged with each other in this state and the stored state is maintained. However, the present invention is not limited to this. An engagement projection may be provided to engage both when the stacker 13 is in the stored state. In this case, when the stacker 13 is moved and rotated from the stored state, the leading end of the stacker 13 rides on the tray rib 37, thereby releasing or easily releasing the engagement between the engaging projection and the engaging hole. It is good if it can transition to the state. Further, in the unfolded state, the circumferential side plate 53 of the stacker 13 is located on the stacking direction side of the engaging projections so that the conveyed sheets do not get caught. Further, while the engaging projections are facing the stacker-facing surface 50B during the rotation of the stacker 13, the stacker 13 is partially lifted by the tray ribs 37 so that the engaging projections and the stacker-facing surface 50B contact each other. It is desirable to prevent

Furthermore, in the above-described embodiment, the stacker facing surface 50B of the stacker 13 is provided with the engaging projection 56 as an extension body engaging portion, and the tray facing surface 30A of the tray 12 is engaged as a mounting body engaging portion. The case where holes 36 are provided has been described. However, the present invention is not limited to this. It may be provided at a location other than 50B, for example, at a portion of the peripheral side plate 53 located at the left end of the stacker body portion 50 .

Furthermore, in the above-described embodiment, the stacker 13 is elastically deformed when the tip side of the stacker 13 is lifted by the tray ribs 37 by configuring the stacker 13 with a flexible resin material. . However, the present invention is not limited to this. For example, the stacker 13 may be made of a highly rigid material such as metal so that the stacker 13 as a whole can move in the stacking direction and be biased in the anti-stacking direction. Specifically, for example, the tray boss 33 may be slightly extended in the stacking direction, and a coil spring may be interposed between the flange regulating surface 34S of the flange 34 and the stacker placement surface 50A of the stacker 13. FIG.

Furthermore, in the above-described embodiment, the height of the most projecting portion of the tray rib 37 of the tray 12 (FIGS. 4 and 5) is the height of the most projecting portion of the engaging protrusion 56 of the stacker 13 (FIGS. 7 and 8). The case of making it larger than the height has been described. However, the present invention is not limited to this, and for example, the height of the most projecting portion of the tray rib 37 may be lower than the height of the most projecting portion of the engaging projection 56 . In this case, for example, by using the rounded portion of the projection engaging portion 61 (FIG. 9) of the engaging projection 56, the hole engaging portion 41 (FIG. 9) of the engaging hole 36 is attached to the engaging projection 56. 6) should be overcome.

Furthermore, in the above-described embodiment, the case where the tray rib 37 of the tray 12 (FIGS. 4 and 5) is shaped along the transport direction in which the paper is transported has been described. However, the present invention is not limited to this, and the tray ribs 37 may have various shapes, such as shapes along the trajectory along which the stacker 13 moves and rotates.

Furthermore, in the embodiment described above, the case where the flange 34 is provided on the stacking direction side of the tray boss 33 in the tray 12 (FIGS. 4 and 5) has been described. However, the present invention is not limited to this, and for example, a flange may be provided on the side opposite to the stacking direction of the stacker boss 51 in the stacker 13 so that the tray groove portion 35 of the tray 12 penetrates in the stacking direction. In short, the stacker 13 is moved with respect to the tray 12 while maintaining the state in which the tray facing surface 30A of the tray 12 and the stacker facing surface 50B of the stacker 13 are opposed to each other and kept extremely close to or in contact with each other. and can be rotated.

Furthermore, in the above-described embodiment, the tray 12 (FIGS. 4, 5, etc.) is provided with the tray boss 33 and the tray groove 35, and the stacker 13 (FIGS. 7, 8, etc.) is provided with the stacker boss 51 and the stacker groove 52. Stated. However, the present invention is not limited to this. A mechanism may be used. The point is that at least the stacker 13 can be rotated when the stacker 13 is moved to the retracted state or the unfolded state with respect to the tray 12 .

Furthermore, in the above-described embodiment, a case has been described in which a plurality of inclined portions such as the projection right inclined portion 62, the projection tip inclined portion 63, and the projection left inclined portion 64 are provided on the engaging projection 56 (FIG. 9) of the stacker 13. . However, the present invention is not limited to this, and for example, at least one of the inclined portions may be omitted. Also, the inclination direction of the inclined portion may be various other directions. The point is that when the stacker 13 moves and rotates, the engagement projection 56 can ride on the peripheral portion of the engagement hole 36 .

Furthermore, in the embodiment described above, the case where the inclined hole portion 42 is provided in the engaging hole 36 (FIG. 6) of the tray 12 has been described. However, the present invention is not limited to this, and for example, the inclined hole portion 42 may be omitted. Alternatively, an inclined portion may be provided in another circumferential portion of the engaging hole 36 . In short, when the stacker 13 is in the stored state (FIGS. 10A, 13A, etc.), the projection engaging portion 61 of the engaging projection 56 is engaged with the hole engaging portion 41 of the engaging hole 36. It is sufficient if the engaging projection 56 can be easily moved over the peripheral portion of the engaging hole 36 when the stacker 13 is moved and rotated from the stored state.

Furthermore, in the above-described embodiment, the stacker 13 (FIGS. 7, 8 and 9) is provided with slits 57 along the left-right direction on the root side and the tip side of the engaging projection 56, respectively. However, the present invention is not limited to this, and for example, slits along the transport direction may be provided on the left and right sides of the engaging protrusions 56, respectively. Also, the number of slits is not limited to two, and may be one or three or more. Further, the slits may be formed along different directions, and may have different shapes (length, width, etc.). Moreover, the shape of the slit is not limited to a linear shape, and may be formed in a curved shape. Alternatively, the slit 57 may be omitted.

Furthermore, in the above-described embodiment, the grip portion 55 of the stacker 13 (FIGS. 6 and 7) is positioned at the center in the left-right direction and on the leading end side of the stacker central rib 54 so as to be connected to the stacker central rib 54. The case of providing However, the present invention is not limited to this, and for example, the gripping portion 55 may be provided at a position off the center of the stacker 13 in the left-right direction.

Furthermore, in the above-described embodiment, when the stacker 13 is stored (FIG. 8A), the base portion of the stacker 13 is directed toward the right side of the tray 12, and the tip portion of the stacker 13 is directed toward the tray 12. The case of turning to the left side of . However, the present invention is not limited to this. For example, the base side of the stacker 13 may face the left side of the tray 12 and the tip side of the stacker 13 may face the right side of the tray 12 .

Furthermore, in the above-described embodiment, a case has been described in which the stacker 13 (FIG. 7) is configured in a rectangular shape when viewed from the stacking direction. However, the present invention is not limited to this, and various shapes such as an elliptical shape may be used. In short, the stacker 13 does not protrude from the tray 12 in the accommodated state, and the leading end portion of the stacker 13 is positioned farther in the leading end direction than the leading end portion of the tray 12 in the unfolded state. can be placed.

Furthermore, in the above-described embodiment, the case where the present invention is applied to the rear tray section 7 for placing sheets discharged from the rear opening 2RH in the housing 2 of the image forming apparatus 1 has been described. However, the present invention is not limited to this. may apply.

Furthermore, in the above-described embodiment, a case has been described in which the present invention is applied to the image forming apparatus 1 having a printing function of forming (that is, printing) an image on paper. However, the present invention is not limited to this. The present invention may be applied to a copier, a facsimile machine, or an image forming apparatus that can also operate as an image scanner. Alternatively, the present invention may be applied to various devices that transport and handle paper, such as copiers and facsimile machines.

Furthermore, the present invention is not limited to the embodiments described above and other embodiments. In other words, the scope of the present invention extends to embodiments obtained by arbitrarily combining part or all of each of the above-described embodiments and other embodiments described above, and to embodiments in which a part is extracted. is.

Furthermore, in the above-described embodiment, a case has been described in which the tray 12 as the mounting body and the stacker 13 as the extension body constitute the rear tray section 7 as the medium stacking device. Among them, the mounting body is provided with a tray boss 33 as a mounting projection and a tray groove 35 as a mounting groove, and the extension body is provided with a stacker groove 52 as an extension groove and a stacker boss as an extension projection. 51 was provided. However, the present invention is not limited to this, and the medium mounting device may be configured by a mounting body and an extension body having various other configurations. In this case, the mounting body is provided with mounting protrusions and mounting grooves having various other configurations, and the extension body is provided with extension grooves and extension protrusions having various other configurations. Also good.

INDUSTRIAL APPLICABILITY The present invention can be used, for example, in a tray that is stored in a housing of an image forming apparatus when not in use and unfolded when in use.

Reference Signs List 1 image forming apparatus 2 housing 7 rear tray 11 face-up cover 12 tray 13 stacker 30 tray body 30A tray facing surface 33 Tray boss 34 Flange 34S Flange control surface 35 Tray groove 35X Tray groove center line 35XA Tray groove storage point 35XB Tray groove development point 36 Engagement hole 37 Tray rib 37A Root sloped portion 37B Tip tip sloped portion 41 Hole engaging portion 42 Hole sloped portion 50 Stacker body 50A Stacker placement surface 50B Stacker facing surface 51 Stacker boss 52 Stacker groove 52X Stacker groove center line 52XA Stacker groove storage point 52XB Stacker groove development point 53 Peripheral side plate 54 Stacker central rib 55 Grip portion 56 Engagement projection 57 Slit 61 Projection engagement portion 62 Projection right inclined portion 63 Projection tip inclined Section 64: Projection left inclined portion RA: Stacker storage area.

Claims (19)

a mounting body on which a medium is placed, which is transported in a base direction approaching the main body or in a leading end direction away from the main body along a conveying path connected to the main body;
At least a part of the extended facing surface is opposed to the mounting facing surface of the mounting body, and the position and posture with respect to the mounting body are changed, thereby shortening the length in the conveying direction along the conveying path. an extension body that transitions between a retracted stored state and an expanded state in which the length in the conveying direction is extended;
a facing maintaining part that maintains a facing state in which at least part of the extended facing surface faces the mounting facing surface,
The extension body
further comprising an extension body engaging portion that engages with the mounting body,
The mounting body is
a mounting body engaging portion provided at a position facing the extension body engaging portion in the housed state and engaged with the extension body engaging portion;
The extension body is provided at a position facing the extension facing surface when transitioning between the stored state and the expanded state, protrudes from the mounting facing surface, and extends toward the base direction side of the mounting facing surface. and a mounting rib having a base-side inclined portion that is inclined such that the amount of protrusion from the mounting facing surface increases as the extension moves away from the storage area, which is the area where the extension body in the stored state overlaps. A medium placement device characterized by: The medium stacking device according to claim 1, wherein a portion of the stacking rib on the root direction side is positioned within the storage area. The extension body engaging portion is provided on the extension facing surface,
The medium placement device according to claim 1, wherein the placement body engaging portion is provided on the placement facing surface. The extension body engaging portion is an engaging projection projecting from the extension facing surface,
4. The medium stacking device according to claim 3, wherein the mounting body engaging portion is an engaging hole recessed from the mounting facing surface and engaged with the engaging protrusion in the accommodated state. The extension body has flexibility,
When the amount of protrusion of the most protruding portion of the mounting rib from the mounting facing surface is such that the extension facing surface of the extension body is in contact with the most protruding portion 5. The medium stacking device according to claim 4, wherein the engaging projection is positioned closer to the stacking rib side than the stacking facing surface. 6. The medium mount according to claim 5, wherein the mount rib protrudes from the mount-facing surface by a larger amount than the engaging protrusion of the extension body protrudes from the extension-facing surface. placement device. The medium stacking device according to claim 1, wherein the stacking ribs are formed along the conveying direction. The mounting rib further includes a tip-side sloping portion that is inclined toward the tip direction side so that the amount of protrusion from the mounting facing surface increases as the storage area is approached. Item 1. The medium placement device according to item 1. When the extension facing surface of the extension body abuts against the tip-end-side inclined portion, the mounting body is configured such that the extension body engaging portion is positioned closer to the tip than the end portion of the mounting facing surface on the distal direction side. 9. The medium stacking device according to claim 8, wherein the position of the end portion on the leading end direction side of the stacking facing surface is set so as to be positioned on the direction side. The extension body further includes a gripping portion, which is gripped when the extension body transitions to the stored state or the deployed state, at a portion on the distal direction side in the deployed state,
The medium stacking device according to claim 1, wherein the stacking rib is provided on the tip side of the grip portion in the stored state. The mounting body is
a mounting protrusion provided in a storage area overlapping the extension body in the stored state on the mounting facing surface and protruding from the mounting facing surface;
and a mounting groove portion in which a groove recessed from the mounting facing surface is formed,
The extension body
an extended groove formed with a groove recessed from the extended facing surface for guiding the insertion of the mounting protrusion;
an extension protrusion projecting from the extension facing surface and guided by being inserted into the mounting groove,
2. The medium holder according to claim 1, wherein the facing maintenance unit inserts the mounting projection into the extension groove and maintains a state in which the extension projection is inserted into the mounting groove. placement device. The mounting groove portion has a width close to the mounting protrusion in the width direction orthogonal to the transport direction from a mounting groove storage point where the extension protrusion is positioned when the extension body is in the retracted state. formed in a direction including a component in the first direction,
When the extension body is in the retracted state, the extension groove extends in a direction including a component in a second width direction opposite to the first width direction from an extension groove storage point where the mounting protrusion is positioned. formed towards
The extension body engaging portion is an engaging projection projecting from the extension facing surface,
The mounting body engaging portion is an engaging hole that is recessed from the mounting facing surface and engages with the engaging projection in the accommodated state,
The engagement projection is
a protrusion engaging portion formed on the root direction side of the first width direction side in the unfolded state and engaged with the engaging hole;
A protrusion that is formed on the distal direction side of the first width direction side in the unfolded state, and that is inclined such that the amount of protrusion from the extension facing surface increases as it progresses in the second width direction in the unfolded state. further comprising a width first sloped portion;
The engagement hole is
a hole engaging portion formed on the width first direction side and engaged with the projection engaging portion of the engaging projection in the accommodated state;
a hole inclined portion formed on the second width direction side and inclined such that the distance from the mounting facing surface increases as the hole proceeds toward the root direction in the accommodated state. The medium placement device according to claim 11. The engaging projection is formed on the distal direction side in the deployed state, and has a projection distal end inclined portion that is inclined so that the amount of protrusion from the extended facing surface increases as it advances in the root direction in the deployed state. 13. The medium placement device according to claim 12, further comprising: The engaging protrusion is formed on the side of the second width direction in the unfolded state, and is inclined such that the amount of protrusion from the extended opposing surface increases as the protrusion advances in the first width direction in the unfolded state. 13. The medium placement device according to claim 12, further comprising a second width slope. The extension body further includes a gripping portion, which is gripped when the extension body transitions to the stored state or the deployed state, at a portion on the distal direction side in the deployed state,
When the extension body is in the housed state, the extension body engaging portion is configured to accommodate an extension groove housing point at which the mounting projection is positioned in the extension groove and the holding position in a width direction orthogonal to the conveying direction. 12. The medium placement device according to claim 11, wherein the medium placement device is arranged between the part. 2. The extension body according to claim 1, wherein a slit penetrating from the extension facing surface to the opposite side surface is formed in the vicinity of the extension body engaging portion on the extension facing surface. medium placement device. The extension body further includes a gripping portion, which is gripped when the extension body transitions to the stored state or the deployed state, at a portion on the distal direction side in the deployed state,
The medium stacking device according to claim 16, wherein the slit is arranged between the extension body engaging portion and the grip portion. The extension body further includes an extension groove portion formed with a groove recessed from the extension facing surface and guiding a mounting protrusion projecting from the mounting facing surface of the mounting body to be inserted therein,
The medium stacking device according to claim 16, wherein the slit is arranged between the extension body engaging portion and the extension groove portion. a main body that conveys a medium and forms an image;
a mounting body on which the medium is placed, which is transported in a root direction approaching the main body or in a leading end direction away from the main body along a transport path connected to the main body;
At least a part of the extended facing surface is opposed to the mounting facing surface of the mounting body, and the position and posture with respect to the mounting body are changed, thereby shortening the length in the conveying direction along the conveying path. an extension body that transitions between a retracted stored state and an expanded state in which the length in the conveying direction is extended;
a facing maintaining part that maintains a facing state in which at least part of the extended facing surface faces the mounting facing surface,
The extension body
further comprising an extension body engaging portion that engages with the mounting body,
The mounting body is
a mounting body engaging portion provided at a position facing the extension body engaging portion in the housed state and engaged with the extension body engaging portion;
The extension body is provided at a position facing the extension facing surface when transitioning between the stored state and the expanded state, protrudes from the mounting facing surface, and extends toward the base direction side of the mounting facing surface. and a mounting rib having a base-side inclined portion that is inclined such that the amount of protrusion from the mounting facing surface increases as the extension moves away from the storage area, which is the area where the extension body in the stored state overlaps. An image forming apparatus characterized by:

Images