JPH08244986A - Sheet loading means and image forming device provided with it - Google Patents

Abstract

PURPOSE: To miniaturize a sheet loading means by linking a subtray with a sheet loading base through a guide means movably straightly and rotationally, so that the subtray is received in the direction meeting at right angles with the sheet carrying direction of the sheet loading base and drawn out in the sheet carrying direction. CONSTITUTION: A subtray 1 is between a subtray stopper part 8 and a subtray guide part 9 in the received condition in a sheet loading base 4. The subtray 1 is moved straightly and rotationally by a guide means G, drawn out in the full line position, and the side is brought in contact with the subtray guide part 9, locked by a lock means 7, and loads a sheet together with the sheet loading base 4. Namely, the subtray 1 is linked with the sheet loading base 4 through the guide means G, moved straightly and rotationally, and drawn out by the length of a slotted hole 2. Consequently, the length of the subtray 1 can be shortened, the width of the sheet loading base can be shortened, and hence a sheet loading means Y can be miniaturized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet stacking means for stacking sheets and an image forming apparatus equipped with the sheet stacking means, which is used in an image forming apparatus or the like.

[0002]

2. Description of the Related Art A sheet supporting unit (sheet stacking table) is provided in a sheet feeding unit or a sheet discharging unit of an image forming apparatus so that sheets of different sizes can be stacked. There is a sheet stacking unit configured to be able to extend and contract.

FIG. 6 shows such a conventional example. In this conventional example, a sub tray 11 is mounted on a sheet stacking base 12.
Is accommodated, and the expansion / contraction direction of the sub-tray 11 is linear. The sub-tray 11 has a guide portion 16 from a position 17 indicated by a chain double-dashed line to a position indicated by a solid line.
The flange portion 15 at the end is locked by the locking means 13 that elastically deforms in the radial direction.

In the case of this conventional structure, the length of the sub-tray 11 is completely stored within the outline of the sheet stacking table 12 when it is stored in the sheet stacking table 12, and does not travel outside the sheet stacking table 12. In order to do so, it is necessary to make the length of the sheet stacking table 12 or less. Therefore, when the sub-tray 11 is pulled out from the sheet stacking table 12, the length capable of supporting the sheet is substantially the length of the sub-tray.

Further, as shown in FIG. 7, there is also known a conventional one in which the sub tray 11 is rotated and pulled out from the sheet stacking means 12, that is, a rotary motion system.

In the case of this conventional example, the sub tray 11 has one
When only the book is attached to the sheet stacking table 12, the center of the width of the sheet is received, and the length is about half the width of the sheet stacking table on the side where the sheets are stored.

Further, as shown in FIG. 8, it is known that the sub trays 11 are attached to both sides of the sheet stacking base 12 and the both width ends of the sheet are supported by the sub trays 11. In this conventional example, the length of the sub-tray 11 is about half the sheet width, as in the case shown in FIG. 7 (when only one sub-tray 11 is provided).

[0008]

As described above, as shown in FIG.
In the conventional example shown in (1), the length at which the sheets can be supported by the sub tray 11 is limited by the length of the sheet stacking table 12.

Further, in the conventional example shown in FIGS. 7 and 8, the length at which a sheet can be supported by the sub-tray 11 is limited by the width of the sheet stacking base 12 in which the sub-tray 11 is stored, and the sheet stacking base 12 is the longest. It is about half the width of. Therefore, in the conventional example shown in FIGS. 7 and 8, when a sheet is supported by the sub-tray 11, in order to secure the same sheet support length as in FIG. 6, the sheet stacking base 12 shown in FIG. The sheet stacking table 12 is required.

In any of the conventional examples described above, in order to achieve a sub-tray length that satisfies the function of supporting sheets, the structure of the sheet stacking means must be increased,
It has been difficult to meet the demand for miniaturization of the sheet stacking means.

Therefore, an object of the present invention is to reduce the size and cost of the sheet stacking means without impairing the sheet supporting function.

[0012]

SUMMARY OF THE INVENTION The present invention has been devised in view of the above-mentioned problems, and provides a sub-tray that is pulled out from the sheet stacking table in the sheet conveying direction and cooperates with the sheet stacking table to support the sheet. A sheet stacking means including a guide means for guiding the sub-tray to the sheet stacking table so that the sub-tray can be pulled out in a direction along the sheet transporting direction from a state where the sub-tray is stored in a direction orthogonal to the sheet transporting direction of the sheet stacking table. It is characterized in that it is connected so as to be linearly movable and rotatable via.

According to the present invention, the guide means is fixed to an elongated hole formed in one of the sub-tray and the sheet stacking table and the other of the sub-tray and the sheet stacking table, and The sheet stacking means according to claim 1, further comprising: a guide shaft slidably engaged with the hole.

In the sheet stacking means of the present invention, the guide means is a rotation guide groove formed in one of the sub-tray and the sheet stacking table, and the other one of the sub-tray and the sheet stacking table. And a rotation guide shaft that is slidably engaged with the rotation guide groove.

In the sheet stacking means of the present invention, when the sub-tray is pulled out from the sheet stacking table by a predetermined amount,
Locking means for locking the sub-tray with respect to the sheet stacking table is provided in the guiding means.

Further, the image forming apparatus of the present invention is characterized by including any one of the above-mentioned sheet stacking means for stacking sheets and an image forming means for forming a desired image on the sheets.

[0017]

When a large-size sheet cannot be supported only by the sheet stacking table, when the operator pulls out the sub-tray attached to the sheet stacking table, the sub-tray is guided by the guide means to linearly move and rotate, so that the sheet stacking table is rotated. The sub-tray accommodated in the direction orthogonal to the sheet conveying direction is pulled out in the direction along the sheet conveying direction, and the sub-tray cooperates with the sheet stacking base to support the sheet.

[0018]

Embodiments of the present invention will now be described in detail with reference to the drawings. <Embodiment 1> FIGS. 1, 2 and 5 show a first embodiment of the present invention.

In FIG. 1, the sheet stacking table 4 on which sheets are stacked has linear portions 5a and 5b on both sides and curved portions 5c.
A guide groove (rotation guide groove) 5 connected with is formed. A guide shaft portion (rotation guide shaft) 3 fixed to the sub-tray 1 is slidably engaged with the guide groove 5. The right end portion of the guide groove 5 in FIG. 1 is elastically engaged (locked) with the guide shaft portion 3 of the sub-tray 1 and elastically deformed in the direction of expanding the groove width (locking means). 7 are formed. The lock portion 7 is formed such that the center of the sub-tray 1 is located substantially at the center of the sheet stacking table 4 in the width direction.

A flange shaft portion 6 extending toward the side of the sub tray 1 is attached to the sheet stacking table 4. The flange shaft portion (guide shaft) 6 is slidably engaged with the elongated hole 2 formed in the sub tray 1.

The sub-tray 1 is an elongated plate member,
As described above, the guide shaft portion 3 is slidably engaged with the guide groove 5 of the sheet stacking base 4, and the elongated hole 2 is slidably engaged with the flange shaft portion 6, as shown in FIG.
It is pulled out while being rotated from a position indicated by a chain double-dashed line (storage position; a direction orthogonal to the sheet conveying direction) to a position indicated by a solid line (drawing position; a direction along the sheet conveying direction). That is, the sub-tray 1 is drawn out further in the upper direction (sheet conveying direction) in FIG. 1 by the length of the elongated hole 2. The guide groove 5, the guide shaft portion 3, the elongated hole 2, and the flange shaft portion 6 constitute a guide means G for moving the sub-tray 1 in a predetermined direction.

The sub-tray 1 is located between the sub-tray stopper portion 8 and the sub-tray guide portion 9 when it is stored in the sheet stacking table 4 (indicated by the chain double-dashed line).
The tip portion 10 does not project outside the contour of the sheet stacking table 4. Then, the sub-tray 1 is linearly and rotationally moved by the guide means G, is pulled out to the solid line position in FIG. 1, and the side surface on the left side in FIG. It is locked at that position at 7, and cooperates with the sheet stacking base 4 to stack and support sheets.

As described above, in this embodiment, the sub-tray 1 is connected to the sheet stacking table 4 through the guide means G, and the sub-tray 1 is caused to move linearly and rotationally by the guide means G. It adopts a simple configuration in which it is pulled out by the length of the extra length. Therefore, according to the present embodiment, the length of the sub-tray 1 can be made shorter than that of the conventional example with a simple structure, and the size of the sheet stacking table 4 in the width direction (left-right direction in FIG. 1) is shortened. Therefore, the size and cost of the sheet stacking means Y can be easily reduced.

The sheet stacking means Y of this embodiment may be arranged on either the sheet supply side or the sheet discharge side. That is, the sheet stacking unit Y can be used as a sheet supply tray or a sheet discharge tray.

FIG. 2 shows a mode in which the sheet stacking means Y is used as a sheet supply tray of the image forming apparatus 18. When a desired image is formed on a large sheet, a sheet stacking unit Y as a sheet supply tray
The sub-tray 1 is used by pulling it from the sheet stacking table 4.

FIG. 5 shows an example in which the sheet stacking means Y is applied to an extension tray of the paper discharge section 19 of the image forming apparatus 18. When ejecting a large-sized sheet on which an image has been formed, the sub-tray 1 is pulled out and used as shown in the figure. <Second Embodiment> FIGS. 3 and 4 show a sheet stacking means Y according to a second embodiment of the present invention. Of these, FIG. 3 is a view seen from the back surface side of the sheet stacking table 4. or,
FIG. 4 is a view seen from the front surface side of the sheet stacking table 4.

As shown in these figures, the sheet stacking table 4
A guide shaft portion (rotation guide shaft) 3 is fixed to the back surface side of the. A substantially arcuate guide groove (rotation guide groove) 5 of the sub-tray 1 is slidably engaged with the guide shaft portion 3. Further, the sheet stacking base 4 is formed with an elongated hole 2 extending substantially in the center of the sheet stacking base 4 in the width direction (horizontal direction in FIG. 3) and in the sheet conveying direction (vertical direction in FIG. 3). . A flange shaft portion (guide shaft) 6 fixed to the sub-tray 1 is slidably engaged with the elongated hole 2.

As shown by the chain double-dashed line in FIG. 3, the sub-tray 1 is stored on the back side of the sheet stacking base 4 in a state of being oriented in the direction orthogonal to the sheet conveying direction. In this stored state, the side surface of the sub-tray 1 is in contact with the sub-tray stopper portion 8 and the sub-tray guide portion 9, and the leading end portion 10 thereof does not project outside from the contour of the sheet stacking table 4. . The guide groove 5 and the guide shaft portion 3, the elongated hole 2 and the flange shaft portion 6 constitute the guide means G.

A lock portion 7 is formed at the left end of the guide groove 5 of the sub tray 1. Similar to the first embodiment, the lock portion 7 is elastically deformable in the direction in which the groove width of the guide groove 5 is widened, and elastically locks the guide shaft portion 3.

When the sheet stacking means Y of the present embodiment having the above-described structure is pulled out from the position indicated by the chain double-dashed line in FIG. 3 to the position indicated by the solid line, it performs a combined motion of rotary motion and rotary motion,
An extra amount of the length of the slot 2 is pulled out in the sheet conveying direction.

Therefore, in the present embodiment, as in the first embodiment, the length of the sub-tray 1 can be made shorter than that of the conventional example with a simple structure, and the width direction of the sheet stacking base 4 ( Since the dimension in the left-right direction in FIG. 1) can be shortened, it is possible to easily reduce the size and cost of the sheet stacking unit Y.

In the above embodiment, the guiding means G
Is composed of the guide groove 5 and the guide shaft portion 3, the elongated hole 2 and the flange shaft portion 6, but only one of the guide groove 5 and the guide shaft portion 3 and the elongated hole 2 and the flange shaft portion 6 is formed. It may be configured. Further, which side of the sheet stacking base 4 and the sub-tray 1 the guide groove 5, the guide shaft portion 3, the elongated hole 2, and the flange shaft portion 6 are to be arranged is appropriately determined. <Image Forming Apparatus> FIG. 9 shows an image forming apparatus using the sheet stacking means Y of each of the above embodiments.

In FIG. 9, the sheets S stacked in the cassette 50 constituting the sheet feeding device A are picked up by the half-moon shaped feeding roller 25 and separated sheet by sheet by the pair of sheet material separating rollers 20. Then, the conveyance roller pair 30 conveys the pre-registration guide 51 to the registration roller pair 52.

Thereafter, the sheet S is conveyed by the registration roller pair 52 in accordance with the photosensitive drum (image forming means) 53 as a photosensitive member, and the transfer roller 54 transfers the toner image on the photosensitive drum 53 to the sheet S. Next, the sheet S is guided by the separation guide 55, the conveyance guide 56, and the entrance guide 57, and is heated and pressed by the roller pair of the fixing roller 58 and the pressure roller 59, and the toner image is fixed as a permanent image.

At this time, since the sheet S is wrapped around the fixing roller 58, it is forcibly separated by the separating claw 60, conveyed by the fixing paper discharge rollers 61 and 62, and conveyed along the conveying guide rib 64. .

Further, the sheet S is transported by the transport roller pair 65 along the transport guides 66 and 67, and is discharged and stacked on the face-down tray T by the discharge device 68 that also serves as a curl remover. In addition, this face down tray T
The sheet stacking means Y of each of the above-mentioned embodiments is incorporated to surely stack and stack sheets regardless of the size of the sheet.
Can support.

The image forming apparatus of this embodiment is equipped with the sheet stacking means Y of each of the above-described embodiments, so that not only downsizing of the face down tray T but also downsizing and cost reduction of the image forming apparatus itself can be achieved. You can

[0038]

As described above, according to the present invention, the sub-tray is mounted on the sheet stacking table so that the sub-tray can be pulled out in the direction along the sheet transporting direction from the state where the sub-tray is stored in the direction orthogonal to the sheet transporting direction of the sheet stacking table. Since the sub-tray is linked via the guide means so as to be linearly movable and rotatable, even if the length of the sub-tray is short, the sub-tray can be pulled out from the sheet stacking table enough to support a large-sized sheet. . Therefore, according to the sheet stacking unit of the present invention, it is possible to reduce the size and cost of the structure of the sheet stacking unit.

Further, in the sheet stacking means of the present invention, since the sub-tray is pulled out while rotating, the operation amount of the sub-tray can be small.

Further, since the image forming apparatus of the present invention is equipped with the sheet stacking means of which the size and cost are reduced, the structure of the apparatus can also be reduced in size and cost.

[Brief description of drawings]

FIG. 1 is a plan view of sheet stacking means showing a first embodiment of the present invention.

FIG. 2 is a perspective view of an image forming apparatus using the sheet stacking unit.

FIG. 3 is a bottom side plan view of the sheet stacking unit showing the second embodiment of the present invention.

FIG. 4 is a top plan view of the sheet stacking unit showing the second embodiment of the present invention.

FIG. 5 is a perspective view of an image forming apparatus showing another usage example of the sheet stacking unit according to the first exemplary embodiment of the present invention.

FIG. 6 is a plan view of a sheet stacking unit showing a first conventional example.

FIG. 7 is a plan view of a sheet stacking unit showing a second conventional example.

FIG. 8 is a plan view of a sheet stacking unit showing a third conventional example.

FIG. 9 is a schematic configuration diagram of an image forming apparatus using the sheet stacking unit of the present invention.

[Explanation of symbols]

 1 ... Sub tray 2 ... Slotted hole (guide means) 3 ... Guide shaft part (rotating guide shaft, guide means) 4 ... Sheet stacking table 5 ... Guide groove ( Rotation guide groove, guide means) 6 ... Flange shaft portion (guide shaft, guide means) 7 ... Lock means 53 ... Photosensitive drum (image forming means) 18 ... Image forming apparatus G ... Guide means Y ... Sheet stacking means

Claims (5)

[Claims] 1. A sheet stacking device including a sub-tray that is pulled out from a sheet stacking table in the sheet transporting direction and supports a sheet in cooperation with the sheet stacking platform, wherein the sub-tray is in the sheet transporting direction of the sheet stacking platform. A sheet stacking device which is linearly movably and rotatably connected to the sheet stacking table through guide means so as to be pulled out in a direction along the sheet conveying direction from a state of being housed in the orthogonal direction. means. 2. The guide means is fixed to an elongated hole formed in one of the sub-tray and the sheet stacking table, and fixed in the other of the sub-tray and the sheet stacking table, and is slidable in the elongated hole. The sheet stacking means according to claim 1, further comprising: a guide shaft engaged with the sheet. 3. The guide means is fixed to either one of the sub-tray and the sheet stacking table, and a rotation guide groove formed in one of the sub-tray and the sheet stacking table. 3. The sheet stacking unit according to claim 2, further comprising: a rotation guide shaft slidably engaged with the groove. 4. The guide means is provided with a locking means for locking the sub-tray with respect to the sheet stacking table when the sub-tray is pulled out from the sheet stacking table by a predetermined amount. The sheet stacking unit according to claim 3. 5. An image forming apparatus comprising: the sheet stacking unit according to claim 1 for stacking sheets; and an image forming unit for forming a desired image on the sheet.