JPH07133044A - Paper feeding device - Google Patents

Abstract

PURPOSE:To provide a paper feeding device which facilitates the demounting of a sheet placing plate and can surely carry out the positioning in the direction vertical to the transfer direction of the sheet placing plate. CONSTITUTION:As for a paper feeding device equipped with a sheet placing plate 1 which is constituted so as to be shiftable between a paper feeding position permitting paper feed and a retreat position where paper feed is not carried out, in a paper feeding mechanism for transferring a paper sheet into an image forming device body, a positioning member 6 for the positioning in the direction perpendicular to the sheet feeding direction is provided, and the positioning member is arranged so as to make contact with the sheet placing plate only in the case where the sheet placing plate shifts to the paper feeding position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding device applied to an image forming apparatus such as a copying machine or a laser printer, and more particularly to a sheet feeding mechanism for feeding and feeding the image forming apparatus main body. The present invention relates to a sheet feeding device including a sheet placing plate configured to be movable between a sheet feeding position where paper can be fed and a retracted position where feeding is not performed.

[0002]

2. Description of the Related Art As a sheet feeding device for feeding a sheet as a recording material into an image forming apparatus main body, a side fulcrum is provided on a side plate of the apparatus main body, and at the time of sheet feeding, the sheet is rotated to a substantially horizontal sheet feeding position. It is known to have a hinged door paper feed plate configured to open a mouth for manual paper feeding, raise it when it is not needed, move to a retracted position where it comes into planar contact with the apparatus housing, and close the paper feed opening.

For example, in Japanese Utility Model Publication No. 3-48107, a single sheet is commonly used and a first sheet stacked in a sheet feeding cassette and a second sheet manually fed along a manual sheet feeding table. A sheet feeding device for feeding any of the above is disclosed. The manual paper feed tray is rotatably supported by a pair of support arms pivotally mounted on the side plate of the main body of the device, and when not feeding, it is attracted to the magnetic catch and attached to the panel plate. It is held in a vertical position, and when feeding, it is removed from the panel plate and rotated to the manual feeding part, and due to the presence of its guide arm, it is inserted between the feed roller and the top sheet in the paper feeding cassette. It is like this.

In addition to the type in which the feed rollers are commonly used, a plurality of sheet feeding cassettes are stacked and accommodated in the lower part of the main body of the apparatus in order to reduce the installation space. The side of the main body chassis where the sheet transport path to the image forming unit is almost straight, when the paper cassette is pulled out for work and continuous feeding is not necessary or when images are formed on sheets of a size other than the specified size. An increasing number of image forming apparatuses have a structure in which a hinged door type paper feeding plate for manual paper feeding is provided at the position. In such an apparatus, each paper feed cassette or paper feed plate is provided with a dedicated feed roller or the like.

[0005]

In the paper feeding section for manual paper feeding as described above, the leading edge of the sheet should be aligned in the direction perpendicular to the sheet feeding direction so that skew correction may be small. A paper feed plate or a paper feed table is directly supported by a side plate of the apparatus main body so as to be rotatable.
By doing so, the sheet feeding plate and the like are not displaced with respect to the apparatus main body, and therefore the sheet placed on the sheet feeding plate and the like is unlikely to have the displacement in the direction perpendicular to the feeding direction. The positioning with respect to the image formed in the main body of the apparatus becomes easy.

For example, as shown in FIGS. 5 and 6,
The manual feed table 1 is rotatably supported by a rotation fulcrum 2, that is, support pins 2a and 2b attached to the apparatus housing, and is provided with respect to a separation feeding mechanism including a feed roller 3, a reverse roller 4, and a pickup roller 5. It is configured to be movable between the paper feeding position and the retracted position. This manual stand 1
Is held by a holding means (not shown) such as a magnet catch in the retracted position shown by the alternate long and short dash line in FIG. 5, and is arranged so as to form a part of the outer side surface 100 of the apparatus. Further, at the sheet feeding position shown by the solid line in FIG. 5, which is rotated about the rotation fulcrum 2 and moved, the sheet is held in contact with the stopper portion 100a formed on the lower edge of the outer side surface 100.

As shown in FIG. 6, a pair of side fences 8 that come into contact with and separate from each other are provided on the manual feed stand 1 to define the position of the sheet placed on the manual feed stand 1. The placed sheets are fed out by the pickup roller 5 in the directions of the feed roller 2 and the reverse roller 3, and the double-fed sheets are separated one by one by this roller pair.
After passing through the guide plate 10 shown in FIG. 3, the registration roller 9 sends the image to the image forming unit at a timing.

On the other hand, the feed roller for separating and feeding the sheets one by one from the sheet placing portion is generally made of rubber, which is a high-friction member, and needs to be replaced depending on the degree of wear. At that time, the sheet mounting portion should be removed from the apparatus main body because it hinders the replacement work, but it is not easy to remove it for the purpose of preventing the above-described displacement.

For example, as shown in FIG. 7A, the support pin 2a and the side plate 1 attached to the side plate 101 of the apparatus housing.
When removing the manual feed stand 1 supported by 2b attached to 02, as shown in FIG. 7B, the fixing screw 15 for screwing the support pin 2a to the side plate 101 is removed,
By removing the support pin 2a and moving the manual feed stand 1 along the axial direction coinciding with the position of the support pin, it can be detached from the apparatus main body.

Further, as shown in FIG. 8, support pins 2a and 2 which are planted in the device housing side plates 101 and 102, respectively.
In some cases, the manual feed stand 1 supported and positioned by b is bent to remove it from the apparatus main body. Such a manual feed stand 1 is made of a flexible material such as resin. However, in such a removal method, if the operator mistakenly applies an excessive force, the manual feed stand may fall off from the apparatus main body.

The present invention has been made in view of such a background, and facilitates the removal of the sheet placing plate and ensures the positioning of the sheet placing plate in the direction perpendicular to the feeding direction. An object is to provide a paper device.

[0012]

In order to solve the above-mentioned problems, according to the present invention, a sheet feeding position for feeding a sheet to a sheet feeding mechanism for feeding a sheet in an image forming apparatus main body In a sheet feeding device provided with a sheet placing plate configured to be movable between a retracted position and a retracted position, a positioning member that performs positioning in a direction perpendicular to the sheet feeding direction is provided, and the positioning member is The sheet placing plate is arranged so as to come into contact with the sheet placing plate only when the sheet placing plate moves to the sheet feeding position.

A sheet mounting plate configured to be movable between a sheet feeding position where sheet feeding is possible and a retracted position where sheet feeding is not performed with respect to a sheet feeding mechanism for feeding and feeding the sheet into the main body of the image forming apparatus. The above-described problem can also be solved by configuring the sheet placing plate to be removable only when the sheet feeding device is provided between the sheet feeding position and the retracted position.

[0014]

The details of the present invention will be described based on the embodiments shown in the drawings. The same reference numerals are given to members that are the same as or considered to be the same as those in the conventional example.

As shown in FIG. 1, the manual feed table 1 is supported rotatably around a rotation fulcrum 2. In the main body of the apparatus, there is a pickup roller 5 that comes into contact with a sheet placed on the manual feed stand 1 and feeds the sheet. The roller 5 is moved to the sheet every time a sheet feeding operation is performed by a contacting / separating mechanism (not shown). Contact and separation are repeated. On the downstream side of the pickup roller 5 in the feeding direction, a feed roller 3 that constitutes a separating mechanism is provided.
And the reverse roller 4 are arranged in contact with each other.
The sheet fed by the pickup roller 5 is sandwiched between the feed roller 3 and the reverse roller 4, separated one by one, and conveyed to the registration roller 9 via the guide plate 10.

As shown in FIG. 2, a pair of side fences 8 which can be brought into contact with and separated from each other are provided on the manual feed stand 1 to define the position of the sheet placed on the manual feed stand 1. In this embodiment, a rack and pinion (not shown) slides on the manual feed stand 1 so that the center position of the sheet coincides with the center of the conveyance path where the pickup roller 5, the feed roller 3, and the reverse roller 4 are located. Is configured to. A rib 12 is formed on the support piece 11 of the manual feed stand 1 that is connected to the support pin 2b corresponding to the rotation fulcrum, and has a stronger structure than the support piece portion on the front side of the drawing shown by the broken line.

At the retracted position shown by the alternate long and short dash line in FIG. 1, the manual feed table 1 is held by a magnet catch (not shown) and constitutes a part of the outer side surface 100 of the apparatus.
Further, when the manual feed table 1 rotates about the rotation fulcrum 2 and moves to the sheet feeding position shown by the solid line in FIG.
The position is regulated by abutting on a stopper portion 100a formed on the lower edge of 0. As partially seen in FIG. 2, the device housing side plate 102 on which the support pin 2b is implanted is further provided with a positioning abutment pin 6 having a spherical tip.

The positioning abutment pin 6 is shorter than the support pin 2b, as is clear from FIG.
Is in the sheet feeding position, that is, the position shown by the solid line in FIG. 1 and the positional relationship shown in FIG. Has become. On the other hand, the support piece 13 near the side plate 101 is fitted with the support pin 2a, and the snap-fit type retaining ring 7 prevents the manual feed stand 1 from falling off.

As shown in FIG. 3C, the support pin 2a on the side plate 101 of the apparatus housing and the contact pin 6 on the side plate 102 side.
The distance L ₁ between the tips and the width L ₂ of the manual feed stand 1 are configured so that L ₂ is slightly larger, so that when the manual feed stand 1 moves from the retracted position to the paper feed position. ,
Since the support piece 11 of the manual feed table 1 and the contact pin 6 surely contact each other, and the rib 12 is formed on the support piece 11, the support piece 13 is stronger than the support piece 13 side.
The side slightly bends, and the manual feed stand 1 as a whole has a shape that follows the positioning contact pin 6. As a result, the position of the manual feed stand 1 in the direction perpendicular to the feeding direction is determined.

When removing the manual feed stand 1, the support pin 2 is used.
The retaining ring 7 attached to a is removed, and as shown in FIG. 4, the manual feed stand 1 is tilted to a position approximately halfway between the paper feed position and the retracted position. By tilting in this way, the manual feed stand 1 is released from the constraint by a magnetic catch (not shown), and the contact pin 6 on the support piece 11 on the back side of the manual feed stand 1 is also removed. As a result, as shown in FIG. 3 (b), the manual feed stand 1 is moved along the support pin 2 b to the side plate 1.
It can be slid so as to come close to 02, and can be freely removed from the device housing.

[0021]

According to the first aspect of the present invention, the positioning member provided for positioning in the direction perpendicular to the sheet feeding direction is provided when the sheet placing plate is located at the sheet feeding position. Since it is disposed so as to contact the sheet placing plate only, the positioning of the sheet placing plate in the direction perpendicular to the sheet feeding direction is ensured, and when the sheet placing plate is not in the sheet feeding position. The positioning member does not get in the way when the mounting plate is removed.

According to the second aspect of the invention, the sheet placing plate is configured to be removable only when the sheet placing plate is located between the sheet feeding position and the retracted position. The mounting plate can be removed without impairing the positioning at the position.

[Brief description of drawings]

FIG. 1 is a schematic end view of a sheet feeding device according to an embodiment of the present invention.

FIG. 2 is a schematic perspective view corresponding to FIG.

3A and 3B are views for explaining a positional relationship between a manual feed stand and an apparatus housing, FIG. 3A shows a case where the manual feed stand is at a sheet feeding position, and FIG. 3B shows a case where the manual feed stand is removed. Figure 3 (c) shows
The relationship between the distance between the support pin and the contact pin and the width of the manual feed stand is shown.

FIG. 4 is a schematic end view showing a positional relationship when the manual feed stand is removed.

FIG. 5 is a schematic end view of a sheet feeding device according to a conventional example.

FIG. 6 is a schematic perspective view corresponding to FIG.

FIG. 7 is a view for explaining the removal of the manual feed stand in the conventional example, and FIG. 7A shows a fixed state of the manual feed stand.
(B) shows the state at the time of removal.

FIG. 8 is a diagram illustrating the removal of the manual feed stand in another conventional example.

[Explanation of symbols]

 1 Manual Feeder 2 Rotational Support Point 3 Feed Roller 4 Reverse Roller 5 Pickup Roller 6 Positioning Contact Pin 9 Registration Roller 10 Guide Plate 100 Device Outside Side

Claims (2)

[Claims] 1. A sheet stacking unit configured to be movable between a sheet feeding position where sheet feeding is possible and a retracting position where sheet feeding is not performed, with respect to a sheet feeding mechanism for feeding and feeding the sheet into an image forming apparatus main body. A sheet feeding device including a placing plate includes a positioning member that performs positioning in a direction perpendicular to the sheet feeding direction, and the positioning member is provided only when the sheet placing plate moves to the sheet feeding position. A sheet feeding device, which is disposed so as to come into contact with a sheet placing plate. 2. A sheet loading mechanism configured to be movable between a paper feeding position where paper can be fed and a retreat position where paper is not fed, with respect to a feeding mechanism for feeding paper into the main body of the image forming apparatus. A sheet feeding device provided with a placing plate, wherein the sheet placing plate is configured to be removable only when located between the sheet feeding position and the retracted position.