Information
-
Patent Grant
-
6746011
-
Patent Number
6,746,011
-
Date Filed
Friday, June 7, 200222 years ago
-
Date Issued
Tuesday, June 8, 200420 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Walsh; Donald P.
- Kohner; Matthew J.
-
CPC
-
US Classifications
Field of Search
US
- 271 97
- 271 162
- 271 164
- 271 105
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International Classifications
-
Abstract
For printer sheet separating and feeding with stack side edge air fluffing assistance from variable size sheet stacks in a sheet feeding tray with at least one repositionable stack side edge guide in an openable machine drawer, the stack edge fluffer system automatically operatively engages the edge guide to provide a preset spacing from the variable side edge positions of various size stacks when said machine drawer is closed, plus an air baffle extension out over the stack, but automatically disengages to provides unobstructed loading when the drawer is opened. It may include an automatically variable length manifold.
Description
Disclosed in the embodiments herein is an improved system for separating and individually feeding sheets, especially print media paper sheets of varying sizes and weights, more reliably from a stack of sheets, with an improved, variable position, stack edge pneumatic fluffer.
By way of background, the use of stack edge fluffers or air knives to help separate and/or levitate sheets for improved sheet separation and feeding is an extensively developed art, with numerous patents. The following are noted by way of some recent examples of Xerox Corp. U.S. patents with disclosures of such systems, and for other such art cited therein: U.S. Pat. No. 6,186,492 issued Feb. 13, 2001 to Dechau, et al; U.S. Pat. No. 6,264,188 issued Jul. 24, 2001 to Taylor, et al; and U.S. Pat. No. 6,352,255 issued Mar. 5, 2002 to Taylor. Said U.S. Pat. No. 6,186,492 also discloses an example of a reciprocating vacuum feed head or “shuttle feeder,” with which the present embodiment may be desirably combined, but is not limited thereto. Sheet fluffers may also be combined in the same sheet separator/feeder system with what may be alternatively called “air knives” blowing against at least the upper portion of the front, feeding out, or downstream edge of the stack in coordination with the individual sheet acquisition and feeding. Stack fluffing and/or vacuum sheet feeding is particularly desirable for higher speed printing systems, for providing more reliable high speed sheet separation and feeding and also for reduced marking or scuffing of sheet surfaces as compared to “friction retard” or other such sheet separator/feeders which are more commonly used on slower, lower cost, printers.
As used herein, the term “printers” will be understood to broadly include copiers, printers, multifunction devices, etc., with xerographic, ink jet, or other print media printing systems. The term “sheet” as used herein refers to various print media sheets, of various sizes and weights, typically relatively thin, flexible or even flimsy paper, and sometimes even plastic (such as for overhead transparencies).
As is well known in the art, separating individual print media sheets from a stack of sheets reliably, with a very low rate of misfeeds or double-feeds, which can “jam” the printer, is difficult. Paper sheets may have variable sizes, variable curl, variable moisture content, variable thickness, variable weight, variable beam strength, variable surfaces, e.g., glossy or calendared, variable friction, etc. The sheets may even be “edge welded” together from their stack size cutting or brake operation. It may also be desirable to acquire and feed smaller sheets even faster than larger sheets to reduced pitch space between sheets and effectively increase the print rate. Also, sometimes partially preprinted sheets are loaded into an input sheet feed tray from overprinting or duplex (opposite side) printing. Such sheets may have toners, inks or fuser oils on them, or induced curls, further changing their properties and posing additional separation and feeding challenges.
It will also be appreciated that various types of variously slide-mounted or otherwise movable stack edge guides are well known in the art, for various sheet stacking trays, and need not be described in any detail herein. Such edge guides can be reset to the size of the stack of sheets currently being loaded into that tray generally confine the sheets between such guides. The stack side guides can also assist in linear sheet feeding of the sheets in the orthogonal feeding direction. One, or both, opposing side guides may be movable. If both side guides are moveable they may optionally be ganged for coordinated movement towards or away from one another by a rack and pinion connection, as is also well known. E.g., Xerox Corp. U.S. Pat. Nos. 5,511,771 and 5,946,527. This allows for a “center registered” sheet feeding system instead of an “edge registered” system. An “edge registered” system is shown (modified) from FIG. 3 of Xerox Corp. U.S. Pat. No. 6,302,390, and as shown need only have one side guide. In a “center registered” sheet feeding system in which the side guides are so ganged the operator resetting movement of one side guide automatically moves the opposing side guide.
A movable stack end guide may also be additionally provided in sheet feeding trays, opposite from the feed-out end of the stack, movable in the process direction. It may also be movable an angle thereto for substantially centering on the ends of different widths of sheet stacks, as in Xerox Corp. U.S. Pat. No. 6,302,390, the Xerox Corp. “iGen3” product, and FIG. 3.
A specific feature of the specific embodiment disclosed herein is to provide a sheet feeding system for separating and feeding individual print media sheets in a process direction from a variable size stack of print media sheets loaded into a sheet feeding tray having at least one stack side edge alignment guide movable for alignment with said variable sizes of stacks of print media sheets, which sheet feeding tray is in a machine drawer which is openable for said loading of said variable size stacks of print media sheets into said sheet feeding tray, and which machine drawer is closable to allow said and feeding of said individual print media sheets from said sheet feeding tray in said process direction, the improvement comprising a pneumatic stack edge fluffer system for pneumatically assisting said separating and feeding of said individual print media sheets from said sheet feeding tray in said process direction, said pneumatic stack edge fluffer system automatically operatively engaging a side edge of said variable size stack of print media sheets in said sheet feeding tray in variable positions when said machine drawer is closed, and said pneumatic stack edge fluffer system automatically operatively disengaging a side edge of said variable size stack of print media sheets in said sheet feeding tray when said machine drawer is open.
Further specific features disclosed in the embodiment herein, individually or in combination, include those wherein said engagement and disengagement of said pneumatic stack edge fluffer system is cooperative with said movement of said at least one stack edge alignment guide, and/or wherein said pneumatic stack edge fluffer system comprises a telescoping and spring loaded pneumatic manifold mounted in said machine and extending toward said edge of said variable size stack of print media sheets loaded into said sheet feeding tray, and/or wherein said pneumatic stack edge fluffer system includes an extension member extending out over a portion of the upper surface of said stack of print media sheets when said machine drawer is closed, and/or wherein, when said machine drawer is closed, said pneumatic stack edge fluffer system is automatically engaged by said at least one stack edge alignment guide to automatically maintain a preset operative spacing of said pneumatic stack edge fluffer system from the side edge of said stack of print media sheets irrespective of the repositioning of said stack edge alignment guide, and/or a sheet feeding method for separating and feeding individual print media sheets in a process direction from a variable size stack of print media sheets loaded into a sheet feeding tray having at least one stack side edge alignment guide movable for alignment with said variable sizes of stacks of print media sheets, which sheet feeding tray is in a machine drawer which is openable for said loading of said variable size stacks of print media sheets into said sheet feeding tray, and which machine drawer is closable to allow said separating and feeding of said individual print media sheets from said sheet feeding tray in said process direction, the improvement comprising pneumatically assisting said separating and feeding of said individual print media sheets from said sheet feeding tray in said process direction with a stack edge fluffer system by automatically operatively engaging a side edge of said variable size stack of print media sheets in said sheet feeding tray in variable positions with said stack edge fluffer system when said machine drawer is closed, and automatically operatively disengaging said pneumatic stack edge fluffer system from said side edge of said variable size stack of print media sheets in said sheet feeding tray when said machine drawer is open, and/or wherein an air deflector for said pneumatic stack edge fluffer system is automatically extended out over a portion of the upper surface of said stack of print media sheets when said machine drawer is closed, and automatically not extended out over a portion of the upper surface of said stack of print media sheets when said machine drawer is opened to automatically provide unobstructed loading of said print media sheets into said sheet feeding tray and/or wherein, when said machine drawer is closed, said pneumatic stack edge fluffer system is automatically engaged by said at least one stack edge alignment guide to automatically maintain a preset operative spacing of said pneumatic stack edge fluffer system from the side edge of said stack of print media sheets irrespective of the repositioning of said stack edge alignment guide.
As to specific components of the subject apparatus or methods, or alternatives therefor, it will be appreciated that, as is normally the case, some such components are known per se in other apparatus or applications, which may be additionally or alternatively used herein, including those from art cited herein. All references cited in this specification, and their references, are incorporated by reference herein where appropriate for teachings of additional or alternative details, features, and/or technical background. What is well known to those skilled in the art need not be described herein.
Various of the above-mentioned and further features and advantages will be apparent to those skilled in the art from the specific apparatus and its operation or methods described in the example below, and the claims. Thus, the present invention will be better understood from this description of this specific embodiment, including the drawing figures (which are approximately to scale) wherein:
FIG. 1
is a cross-sectional side view of one example of a subject stack side edge fluffer system before operatively engaging (being separated from by drawer opening) a partially shown exemplary stack of print media sheets and an exemplary side edge guide (better illustrated in FIG.
4
);
FIG. 2
is the same illustration of
FIG. 1
but in an operative position with the drawer closed;
FIG. 3
is a top view of one exemplary drawer-mounted print media sheet feed tray and its side and end guides, of the above-cited U.S. Pat. No. 6,302,390, illustrating utilization therein of the embodiment of
FIGS. 1
,
2
and
4
; and
FIG. 4
is a top view of just the stack side edge fluffer system and side guide of FIG.
1
.
Describing now in further detail the exemplary embodiment with reference to the Figures, there is shown in
FIG. 3
, etc., one example of a sheet feeding drawer
10
for a printer which the operator opens to load in additional, or replacement, sheets of a desired size of print media to stack
12
in a sheet feeding tray
14
for feeding sheets individually with a sheet feeder
16
to a printer for printing them. As is well know, the drawer
10
may be integral the printer or in a separate but operatively communicating sheet feeding module, interposer or inserter. The sheet feeding tray
14
typically will have as here at least one repositionable stack side edge guide
20
, which is typically reset by the printer user up against the edge of the stack
12
when the size of the print media sheets is changed. A resettable stack end guide
30
may also be provided. Since reloading or changing print media is a frequent occurrence, it is important that it be easily and rapidly accomplished, without obstruction of the area of the sheet feeding tray
14
into which the print media is being inserted.
Turning now to the novel pneumatic stack edge fluffer system
40
, as may be seen especially from
FIG. 2
, and also with reference to the above-cited U.S. Pat. No. 6,264,188, it is desirably has an air output
42
end maintained closely spaced from the edge of the stack
12
during its operation for effective stack “fluffing” with its airflow. The airflow may be conventionally provide from a blower
44
.
It has found to be desirable to enhance the effectiveness of the stack edge fluffer system
40
for it to have, in operation, an air deflector member
46
extending from the air output end
42
area out over a portion of the top of the stack
12
, as shown. However, it has been found that this air deflector member
46
in that operative position would interfere with the operator loading, or changing, the stack
12
sheet supply in the tray
14
.
Here, in this stack edge fluffer system
40
embodiment, the blower
44
pneumatically connects to a telescoping, variable length, manifold
47
, which is spring-loaded to extend in length in a direction extending towards the stack
12
side and the side guide
20
by a coil or other compression spring
48
. The telescoping manifold
47
here is defined by two mutually slidable coaxial tubes with a stop
49
to limit its maximum extension and to prevent the spring
48
from separating the two tubes.
The stack edge fluffer system
40
, and in particular its telescoping manifold
47
, preferably operatively interacts with the side guide
20
, as will be described. However, the side guide
20
is configured not to block the airflow from the air output end
42
of the telescoping manifold
47
when they are so engaged.
Merely as one example, as shown especially in
FIGS. 2 and 4
, the air output end
42
of the telescoping manifold
47
may have a first guide
42
A, here a notch, engagable with a second guide, here tab
20
A, extending from the outside of the side guide
20
, when the side guide
20
is within range of the maximum extension of telescoping manifold
47
. The air output end
42
of the telescoping manifold
47
here is effectively cantilever mounted from its other or inside end, which is mounted to the machine or module frame, not the drawer
10
, not the tray
14
, and not the side guide
20
. Thus, the whole stack edge fluffer system
40
remains in the machine or module when the drawer
10
is opened.
Whenever the drawer
10
is opened, the tray
14
and its side guide
20
move outwardly with the drawer. This moves the side guide
20
sufficiently away from the maximum extension of the telescoping manifold
47
, and thus the stack edge fluffer system
40
disengages from the side guide
20
, and thus the air deflector member
46
no longer extends out over any portion of the top of the stack
12
, or out over any of the stack loading area of the tray
14
, even for the largest size stack
12
requiring the maximum width (rearward) resetting position of the side guide
20
. Thus loading of any size stack
12
into the tray
14
is thus automatically rendered completely unobstructed by any part of the stack edge fluffer system
40
. Nor is there any need to move or disconnect air hoses.
With the drawer
10
open, the tray
14
side guide(s) may be reset to the desired current stack
12
size, which stack
12
may be unobstructedly loaded therein. Then the drawer
10
may be normally closed.
Automatically during the drawer closure, with no need for operator intervention, when the now-reset inboard side guide
20
moves in to within the maximum extension range of the telescoping manifold
47
, the air deflector member
46
automatically extends out over the top of the new stack
12
. Then the side guide
20
tab
20
A engages the first guide
42
A on the outer end of the telescoping manifold
47
. That mutual engagement is designed or preset to redefine the correct spacing of the air output end
42
of the telescoping manifold
47
from the side edge of the new stack
12
, irrespective of its changed position. That defined and maintained spacing also insures that the edge fluffer will not obstruct sheet feeding by not touching the sheet stack.
The further inward or closing movement of the drawer
10
simply telescopes the manifold
47
, compressing the spring
48
, to allow the drawer
10
to fully close without obstruction and without changing said preset operative position of the pneumatic output of the stack side edge fluffer against the side of the stack.
While the embodiment disclosed herein is preferred, it will be appreciated from this teaching that various alternatives, modifications, variations or improvements therein may be made by those skilled in the art, which are intended to be encompassed by the following claims.
Claims
- 1. In a sheet feeding system for separating and feeding individual print media sheets in a process direction from a variable size stack of print media sheets loaded into a sheet feeding tray having at least one stack side edge alignment guide movable for alignment with said variable sizes of stacks of print media sheets, which sheet feeding tray is in a machine drawer which is openable for said loading of said variable size stacks of print media sheets into said sheet feeding tray, and which machine drawer is closable to allow said separating and feeding of said individual print media sheets from said sheet feeding tray in said process direction, the improvement comprising:a pneumatic stack edge fluffer system for pneumatically assisting said separating and feeding of said individual print media sheets from said sheet feeding tray in said process direction, said pneumatic stack edge fluffer system automatically operatively engaging a side edge of said variable size stack of print media sheets in said sheet feeding tray in variable positions by an automatically telescoping variable length pneumatic manifold when said machine drawer is closed by automatically telescope variable length, and said pneumatic stack edge fluffer system automatically operatively disengaging a side edge of said variable size stack of print media sheets in said sheet feeding tray when said machine drawer is open.
- 2. The sheet feeding system of claim 1, wherein said engagement and disengagement of said pneumatic stack edge fluffer system is cooperative with said movement of said at least one stack edge alignment guide.
- 3. The sheet feeding system of claim 1, wherein said pneumatic stack edge flutter system includes an extension member extending out over a portion of the upper surface of said stack of print media sheets when said machine drawer is closed.
- 4. The sheet feeding system of claim 1, wherein, when said machine drawer is closed, said pneumatic stack edge flutter system is automatically engaged by said at least one stack edge alignment guide to automatically maintain a preset operative spacing of said pneumatic stack edge flutter system from the side edge of said stack of print media sheets irrespective of the repositioning of said stack edge alignment guide.
- 5. In a sheet feeding system for separating and feeding individual print media sheets in a process direction from a variable size stack of print media sheets loaded into a sheet feeding tray having at least one stack side edge alignment guide movable for alignment with said variable sizes of stacks of print media sheets, which sheet feeding tray is in a machine drawer which is openable for said loading of said variable size stacks of print media sheets into said sheet feeding tray, and which machine drawer is closable to allow said separating and feeding of said individual print media sheets from said sheet feeding tray in said process direction, the improvement comprising:a pneumatic stack edge fluffer system for pneumatically assisting said separating and feeding of said individual print media sheets from said sheet feeding tray in said process direction, said pneumatic stack edge fluffer system automatically operatively engaging a side edge of said variable size stack of print media sheets in said sheet feeding tray in variable positions when said machine drawer is closed, and said pneumatic stack edge flutter system automatically operatively disengaging a side edge of said variable size stack of print media sheets in said sheet feeding tray when said machine drawer is open, wherein said pneumatic stack edge flutter system comprises a telescoping and spring loaded pneumatic manifold mounted in said machine and extending toward said edge of said variable size stack of print media sheets loaded into said sheet feeding tray.
- 6. In a sheet feeding method for separating and feeding individual print media sheets in a process direction from a variable size stack of print media sheets loaded into a sheet feeding tray having at least one stack side edge alignment guide movable for alignment with said variable sizes of stacks of print media sheets, which sheet feeding tray is in a machine drawer which is openable for said loading of said variable size stacks of print media sheets into said sheet feeding tray, and which machine drawer is closable to allow said separating and feeding of said individual print media sheets from said sheet feeding tray in said process direction, the improvement comprising:pneumatically assisting said separating and feeding of said individual print media sheets from said sheet feeding tray in said process direction with a stack edge fluffer system by automatically operatively engaging a side edge of said variable size stack of print media sheets in said sheet feeding tray in variable positions with said stack edge fluffer system when said machine drawer is closed, and automatically operatively disengaging said pneumatic stack edge fluffer system from said side edge of said variable size stack of print media sheets in said sheet feeding tray when said machine drawer is open, wherein an air deflector for said pneumatic stack edge fluffer system is automatically extended out over a portion of the upper surface of said stack of print media sheets when said machine drawer is closed, and automatically not extended out over a portion of the upper surface of said stack of print media sheets when said machine drawer is opened to automatically provide unobstructed loading of said print media sheets into said sheet feeding tray.
- 7. The sheet feeding method of claim 6, wherein, when said machine drawer is closed, said pneumatic stack edge fluffer system is automatically engaged by said at least one stack edge alignment guide to automatically maintain a preset operative spacing of said pneumatic stack edge fluffer system from the side edge of said stack of print media sheets irrespective of the repositioning of said stack edge alignment guide.
US Referenced Citations (10)
Foreign Referenced Citations (2)
Number |
Date |
Country |
3616804 |
Nov 1987 |
DE |
04023747 |
Jan 1992 |
JP |