JPH08157089A - Sheet feeding device and image forming device - Google Patents

Abstract

PURPOSE: To secure a space between a sheet conveyance path and an upper storage section in a feeding device fitted with at least the upper and lower sheet storage sections storing sheets and separating the sheets in the sheet storage sections in sequence and feeding them with feeding means. CONSTITUTION: This sheet feeding device is provided with the upper and lower sheet storage sections 1 storing sheets, fitting sections of the upper and lower sheet storage sections 1 capable of fitting at least the upper and lower sheet storage sections 1, and the upper and lower feeding means 2, 12 separating and feeding the sheets in the sheet storage sections 1 fitted to the fitting sections in sequence. The fitting section of the upper sheet storage section 1 holds the upper sheet storage section 1 so that the sheet feeding means 2, 12 side of the upper sheet storage section 1 is inclined upward. A wide space, where an engine substrate 10 or the like is installed, is secured above the upper sheet storage section 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding apparatus having a sheet feeding means for feeding a sheet storage cassette and an image forming apparatus using the sheet feeding apparatus.

[0002]

2. Description of the Related Art As an example of this type of apparatus, there is a laser beam printer (hereinafter referred to as LBP) as shown in FIG. Referring to FIG. 4, reference numeral 1 is a cassette for storing the sheets S, and 2 and 12 are paper feed rollers for separating and feeding the sheets S in the cassettes 1 and 11 from the uppermost one. In the configuration of the same cassette above,
It can be used commonly in the lower tier. Further, the cassettes 1 and 11 are attached and detached from the right side in FIG.

The timing of the sheet S is adjusted by the registration roller pair 3 so that the sheet S is aligned with the image formed on the drum 5 by the laser scanner unit 4. The image is transferred from the drum onto the sheet by the transfer roller 6 and is fixed by the fixing unit 7, and then discharged onto the discharge tray 9 through the reversing path 8. Reference numeral 10 is a substrate for controlling the engine of the LBP, supplying high voltage necessary for the electrophotographic process, and supplying electric power to the motor heater and the like. In order to have such a function, it is desirable that the substrate 10 be near the image forming portion,
Moreover, in order to effectively utilize the space between the cassette and the image forming section, it is effective to arrange the substrate 10 between the cassette and the image forming section in order to reduce the size of the apparatus.

[0004]

However, in the above-mentioned conventional example, since the fixing unit 7 projects largely below the sheet conveying surface, in order to secure a sufficient substrate area and mounting height, the entire apparatus is fixed. I had to raise the height.

Further, when considering a two-stage cassette model as shown in FIG. 4, the height of the apparatus is increased only by arranging the paper feed roller 12 of the lower cassette 11, and in FIG. The left side of was completely dead space and was very inefficient.

[0006]

SUMMARY OF THE INVENTION The present invention has been invented in view of the above-mentioned problems, and includes a seat storage portion for storing a seat, an upper portion on which the seat storage portion can be mounted in at least two upper and lower stages, and A sheet feeding device having a mounting portion of a lower sheet storage portion and upper and lower feeding means for sequentially separating and feeding sheets in the sheet storage portions mounted on the mounting portions of the upper and lower sheet storage portions In, the mounting portion of the upper sheet storage portion, the seat storage portion,
Since the sheet feeding unit side is configured to be held so as to be tilted upward, an image forming apparatus with more space efficiency is provided.

Further, it has a first sheet feeding device composed of a sheet accommodating portion and a feeding means for separating and feeding the sheets in the sheet accommodating portion, and separates and feeds the sheet accommodating portion and the sheets in the sheet accommodating portion. In an image forming apparatus in which a second sheet feeding device including a feeding unit can be added below the first sheet feeding device, the first sheet feeding device is configured such that when the second sheet feeding device is added, By mounting so that the feeding means side is inclined so as to be upward, space efficiency is improved in both the single-cassette model and the double-cassette model.

[0008]

【Example】

(First Embodiment) FIG. 1 is a view best showing the features of the present invention, and the function of each portion is the same as that of the conventional example, so that the description thereof will be omitted. The 12 side is inclined so that it is upward.
The cassette is held by a cassette guide (not shown) and is attached / detached in this tilt direction. The amount of inclination of the upper cassette 11 is almost the same as the outer diameter of the lower paper feed roller 12. Since the upper cassette 11 is inclined as described above, the space between the fixing device 7 and the upper cassette 11 becomes large, and the substrate is provided below the fixing device 7 without increasing the height of the apparatus body as in the conventional example. It is possible to secure a space for mounting.

Further, it is not necessary to form a dead space on the left side of the lower feed roller 12 as seen in the conventional example, and the space can be used efficiently. The tilt angle of the cassette is 1 ° to 1
It is desirable to set it to about 0 °.

As is apparent from FIG. 1, since the upper cassette 1 is inclined, the upper cassette 1 overlaps the lower sheet feeding roller 12 and the upper cassette 1 in the height direction.
It does not interfere with the lower sheet feeding roller 12 when attaching or detaching.

(Second Embodiment) FIG. 2 shows a second embodiment of the present invention, in which a reference numeral 20 designates a double-sided unit connected to the apparatus main body, and a sheet printed on one side by the apparatus main body selects a double-sided printing mode. Sometimes it is conveyed into the duplex unit 20, and one part is discharged onto the tray 22 by the forward / reverse rotation roller 21,
By the reverse rotation of the forward / reverse rotation roller 21, the sheet is conveyed into the re-feeding conveyance path 23.

The sheet S is guided to the vicinity of the upper sheet feeding roller 2 by a sheet re-feeding roller 24 which can rotate and stop independently of other rollers. At this time, the upper sheet feeding roller 2 and the sheet S are not in contact with each other by the sheet pressing means (not shown). Alternatively, the upper sheet feeding roller 2 may have a substantially fan shape so as not to come into contact with the sheet S.

When the signal for the second-side printing is received, the sheet S is conveyed by the re-feeding roller 24 to a position where it can be picked up by the upper feeding roller 2, and the upper feeding roller 2 starts rotating. The sheet is fed and printing on the second side starts.

In such a double-sided unit, the fixing device 7
It is necessary to arrange the re-feeding roller 24 on the lower side of the fixing device 7, and a space must be secured for that purpose. However, with the above-described configuration of the present invention, a space is provided on the lower side of the fixing device 7. This makes it easy to expand the duplex unit.

(Third Embodiment) FIGS. 3A and 3B show a third embodiment of the present invention, in which FIG. 3A is a usage pattern of a single cassette model, and FIG. 3B is a usage pattern of a double cassette model.

The lower cassette unit is optionally connected to a single cassette model. (A) of FIG.
As is clear from comparison of (b), the attitude of the engine part is different between the single cassette model and the double cassette model, and when expanding to the double cassette model, the engine part is tilted so that the paper feed roller side is upward. To be done. Since the inclination of the engine is 1 ° to 10 °, it is within the permissible range such as the paper feed condition, the electrophotographic process condition, and the paper discharge condition.

In this way, by changing the inclination of the image forming section between the single cassette model and the double cassette model,
It is possible to provide the smallest size in both the single-cassette model and the double-cassette model.

Although the electrophotographic system has been described in the above description, the present invention can of course be applied to other image forming apparatuses.

Further, the structure is not limited to the structure in which the sheet is conveyed substantially horizontally from the transfer to the fixing, and the same effect can be obtained in the structure in which the sheet is conveyed obliquely or vertically. It is possible to bring a part of the space to the upper side of the upper cassette and use it effectively as an engine part.

Further, the number of cassettes is not limited to the two-stage cassette, but may be two or more cassettes. Further, the lower stage may be a so-called paper deck instead of a cassette.

[0021]

As described above, according to the present invention,
A sheet storage cassette for storing sheets, an upper and lower cassette mounting portion capable of mounting the sheet storage cassette in at least two upper and lower stages, and sheets in the sheet storage cassette mounted in the upper and lower cassette mounting portions are sequentially separated. In a sheet feeding device having upper and lower feeding means for feeding, the upper cassette mounting portion is configured to hold the sheet storage cassette so that the sheet feeding means side is inclined upward. Eliminating the wasted space beside the lower paper feed roller, the upper cassette can be attached and detached without interference of the lower paper feed roller while overlapping the upper cassette and the lower paper feed roller in the height direction. It is now possible to provide.

Further, the sheet storage cassette has a first sheet feeding device including a sheet feeding means for separating and feeding the sheets in the cassette, and a sheet feeding cassette for separating and feeding the sheets in the cassette. In the image forming apparatus in which the second sheet feeding device including the means can be added below the first sheet feeding device, the first sheet feeding device causes the feeding when the second sheet feeding device is added. By mounting so that the device side is tilted upward, it is possible to provide a space-efficient image forming apparatus for both the single-cassette model and the double-cassette model.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment of an image forming apparatus according to the present invention.

FIG. 2 is a diagram showing a second embodiment of the image forming apparatus according to the present invention.

FIG. 3 is a diagram showing a third embodiment of the image forming apparatus according to the present invention.

FIG. 4 is a diagram showing an example of a conventional image forming apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Upper cassette 2 ... Upper feeding roller 10 ... Substrate 11 ... Lower cassette 12 ... Lower feeding roller 20 ... Duplex unit 21 ... Forward / reverse roller 23 ... Refeeding conveyance path 24 ... Refeeding roller

Claims (5)

[Claims] 1. A sheet storage part for storing a sheet, a mounting part for the upper and lower sheet storage parts, and a mounting part for the upper and lower sheet storage parts, capable of mounting the sheet storage part in at least two upper and lower stages. In a sheet feeding device having upper and lower feeding means for sequentially separating and feeding the sheets in the formed sheet storing portion, the mounting portion of the upper sheet storing portion is the sheet storing portion, and the sheet feeding means side is upward. A sheet feeding device, which is configured to be held so as to be inclined. 2. The sheet feeding device according to claim 1, wherein the sheet storage section is pulled out in the same direction as the sheet is conveyed by the upper and lower feeding means. The sheet feeding device described. 3. The sheet feeding apparatus according to claim 1, wherein the sheet feeding apparatus is connected to the image forming apparatus, and electric power for image formation is provided between the sheet storage section and the image forming section of the image forming apparatus. A substrate for arranging at least a part of supply or control is arranged.
The sheet feeding device described. 4. The sheet feeding apparatus according to claim 1, wherein the sheet feeding apparatus is connected to the image forming apparatus, and the sheet on which an image has been once formed is conveyed to the upper surface of the sheet storage portion to feed the upper sheet. 2. The sheet feeding apparatus according to claim 1, wherein the sheet feeding unit causes the image forming unit to feed the sheet again. 5. A first sheet feeding device comprising a sheet storage section and a feeding means for separating and feeding the sheets in the sheet storage section, and separating and feeding the sheet storage section and the sheets in the sheet storage section. In an image forming apparatus in which a second sheet feeding device composed of feeding means for feeding can be added below the first sheet feeding device, the first sheet feeding device is installed when the second sheet feeding device is added. An image forming apparatus, wherein the image forming apparatus is attached so that the feeding unit side is inclined upward.