Sheet feeding or delivering – Feeding – With means to align sheet
Reexamination Certificate
2002-10-18
2004-12-28
Mackey, Patrick (Department: 3651)
Sheet feeding or delivering
Feeding
With means to align sheet
C271S236000, C271S273000
Reexamination Certificate
active
06834854
ABSTRACT:
BACKGROUND OF THE INVENTION AND RELATED ART STATEMENT
The present invention relates to a sheet supply apparatus mounted to an image forming apparatus (called an image forming apparatus below), such as a copier, printer apparatus or a facsimile machine, and more particularly, it relates to an automatic supply apparatus which is detachably mounted to an image forming apparatus equipped with aligning means that supplies sheets to an image forming means while aligning an edge of supplied sheets to a transport reference member.
Image forming apparatuses are equipped with a supply portion to supply stacked sheets and with image forming means to form images or characters on sheets supplied from the supply portion, and the sheets are transported from the sheet supply portion to the image forming means in a sheet transport path disposed in the image forming apparatus.
In these kinds of image forming apparatus, in order to improve the image forming quality by forming images on predetermined positions on the sheets, an image forming apparatus equipped with aligning means to supply sheets to the image forming means while aligning an edge of the sheets supplied from the sheet supply portion to accurately position the sheets has been provided for practical use. Examples of the image forming apparatuses equipped with such aligning means are disclosed in Japanese Patent Publication No. 08-208078 and U.S. Pat. No. 05,494,277.
The apparatus disclosed is composed of an internal cassette tray for storing sheets inside the image forming apparatus, and the sheets stacked in these cassette trays are supplied to the image forming portion. Normally, the number of sheets stored in these cassette trays is approximately from 250 to 500, so when forming images on a large number of the sheets at a high speed, it is necessary to frequently replenish sheets. For that reason, an automatic sheet supply apparatus that can store a large number of the sheets has been required.
Such a large capacity automatic sheet supply apparatus, as disclosed in Japanese Patent No. 02,625,057 or U.S. Pat. No. 05,368,285, are equipped with an ascending and descending paper deck (support stage) that supports a large number of stacked sheets (generally, approximately from 2,000 to 3,000 sheets) and separation supply means to separate sheets stacked on this paper deck into single sheets and to supply them to a resister roller on the image forming apparatus.
Also, as an apparatus embedded in the image forming apparatus, Japanese Patent Publication (Tokkai) No. 11-30884 disclosed an example of reducing a transport load when transporting on the rollers arranged on the downstream side in the transport path by separating the upstream paired relay rollers after the sheet has reached the downstream side transport rollers. The separation of the paired relay rollers is performed by mounting one roller to a swinging lever and moving this lever using a solenoid.
However, there are several problems associated with mounting the aforementioned aligning means equipped with the conventional large capacity automatic sheet supply apparatus to an image forming apparatus.
Firstly, after the sheets from the automatic sheet supply apparatuses reach the aligning means on the image forming apparatus, they are moved in a direction traversing the sheet transport direction along the transport reference, but when the sheets are nipped in the separation supply means, the sheets are not smoothly moved in the sheet transport reference side. Particularly, increasing the transport force of the alignment means increases the possibility for the sheets to overrun the transport reference, or when using thin sheets, to bent their edges, and with the pressing contact of the separation supply means, alignment is substantially impossible.
Secondly, it is conceivable to arrange the sheet transport reference on the image forming apparatus side or the alignment means on the sheet automatic sheet supply apparatus, but in this case, it would be unavoidable to increase the size of the sheet supply apparatus.
Thirdly, the aforementioned sheet supply apparatus becomes larger to dispose aligning means in the image forming apparatus to perform resister correction for aligning the leading edge of the sheets supplied after separating and supplying the sheets. For that reason, if the resister means is eliminated, only the aligning means corrects the sheets, thereby making it difficult to perform the proper aligning correction when processing sheets with large bends.
OBJECT OF THE INVENTION
The first object of the present invention is to provide a sheet supply apparatus that can use aligning means to securely align a sheet at a reference position even if the sheet supply apparatus is mounted to an image forming apparatus equipped with the aligning means.
The second object of the present invention is to provide an apparatus that can mount a sheet supply apparatus to an image forming apparatus equipped with aligning means, and also to provide a compact apparatus that performs resister correction with the sheet supply apparatus in advance.
The third object of the present invention is to provide an apparatus that can mount a sheet supply apparatus to an image forming apparatus equipped with aligning means, and also to provide a sheet supply apparatus that can separate and supply sheets at a high speed even if the sheets has various thickness.
Furthermore, an object of the present invention is to provide a sheet supply apparatus that can supply sheets efficiently at a high speed through properly supplying or transporting the sheets according to control of a sheet nipping state or a sheet releasing state at a sheet separating means and a resister roller means when the sheets are supplied from the sheet separating means to the resister roller means in the sheet supply apparatus or when the resister roller means performs resister correction and the sheets are supplied downstream.
SUMMARY OF THE INVENTION
In order to attain the aforementioned objectives, the present invention is a sheet supply apparatus that supplies sheets to an image forming apparatus unit having sheet aligning means for aligning the sheets to a predetermined sheet transport reference in a sheet transport direction. The sheet supply apparatus includes sheet storage means for stacking and storing the sheets; sheet pick-up means for feeding the sheets from the aforementioned sheet storage means; separating means having supply rollers for supplying the sheets fed from the aforementioned sheet pick-up means and separating members pressing the aforementioned supply rollers; a pair of resister rollers for feeding the sheets to the aforementioned aligning means after resister correction for aligning a transport direction of the sheets separated and transported in the aforementioned separating means; and a frame for supporting each of the aforementioned means. The sheet supply apparatus is also provided with the first press separating means for the aforementioned supply rollers and the aforementioned separating members to be in a sheet nipping state or a sheet released state, and the second press separating means for the aforementioned pair of the resister rollers to be in a sheet nipping state or a sheet released state.
In the sheet supply apparatus according to the present invention, it is possible for the aligning means to securely align the sheets at a reference position because the sheet nipping state is released after the sheets are fed to the aligning means in the image forming apparatus.
Further, the present invention is an image forming apparatus that comprises the first unit having sheet aligning rollers for aligning sheets at a predetermined sheet transport reference side in the sheet transport direction while transporting the sheets, and the second unit detachably mounted to the aforementioned first unit. The second unit includes sheet storage means for stacking and storing the sheets; sheet pick-up means for feeding the sheets from the aforementioned sheet storage means; separating means having supply rollers for supply
Inoue Hidemi
Kinoshita Hidetoshi
Matsuki Satoru
Kanesaka Manabu
Mackey Patrick
Nisca Corporation
LandOfFree
Sheet supply apparatus and image forming apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Sheet supply apparatus and image forming apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Sheet supply apparatus and image forming apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3312134