U.S. patent number 3,614,089 [Application Number 04/833,530] was granted by the patent office on 1971-10-19 for automatic original feeder for copying machine.
This patent grant is currently assigned to Copystatics Manufacturing Corporation. Invention is credited to Robert Barto, Fritz A. Blank, Lionel Hoffman, Christopher Rush, John A. Van Auken.
United States Patent |
3,614,089 |
Van Auken , et al. |
October 19, 1971 |
AUTOMATIC ORIGINAL FEEDER FOR COPYING MACHINE
Abstract
An automatic feed mechanism for feeding individual sheets in
succession from a stack of sheets. A series of blowers decreases
the pressure above the uppermost sheet in the stack so that it is
raised. The sheet strikes against a series of rotating belts which
cause it to move forward. A series of stripper wheels, rotating in
the same direction as the belt, is disposed forward of the
forwardmost edges of the sheets in the stack and below the belt. In
the event more than one sheet have been lifted from the stack and
are moving in the forward direction, the stripper wheels bear
against the lower surface of the lowermost sheet and force it back
into the stack. The force imparted by the stripper wheels is
greater than the normal friction force between two adjacent sheets.
The stripper wheels have no effect on a single sheet moving in the
forward direction because the reverse force imparted by the wheels
to this sheet is less than the forward force imparted by the
belts.
Inventors: |
Van Auken; John A. (Miami
Beach, FL), Rush; Christopher (Ithaca, NY), Blank; Fritz
A. (Hollywood, FL), Hoffman; Lionel (Fort Lauderdale,
FL), Barto; Robert (Des Peres, MO) |
Assignee: |
Copystatics Manufacturing
Corporation (Miami Lakes, FL)
|
Family
ID: |
25264662 |
Appl.
No.: |
04/833,530 |
Filed: |
June 16, 1969 |
Current U.S.
Class: |
271/94;
271/104 |
Current CPC
Class: |
B65H
3/5261 (20130101); B65H 3/128 (20130101); G03B
27/6264 (20130101) |
Current International
Class: |
B65H
3/52 (20060101); B65H 3/12 (20060101); G03B
27/62 (20060101); B65h 003/12 () |
Field of
Search: |
;271/26,27,28,34,12,30 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
Anderson et al., IBM Technical Disclosure Bulletin Vol. 6, No. 2,
1963, Class 271, Subclass 12, pgs. 32 and 33..
|
Primary Examiner: Wegbreit; Joseph
Claims
What is claimed is:
1. An automatic feed mechanism for feeding individual sheets in
succession from a vertically disposed stack of substantially
horizontal sheets comprising means for lifting the uppermost sheet
in said stack, means for imparting a force in the forward direction
to the uppermost sheet lifted from said stack, and positive means
for imparting a force in the reverse direction to the lowermost
sheet in any group of sheets which may have been lifted from said
stack and are moving in the forward direction, the force imparted
in said reverse direction being greater than the normal friction
force between two adjacent sheets and being less than the force
imparted in the forward direction to the uppermost lifted
sheet.
2. An automatic feed mechanism in accordance with claim 1 wherein
said lifting means includes means for creating a decreased air
pressure above the uppermost sheet in said stack relative to the
sheets underneath said uppermost sheet.
3. An automatic feed mechanism in accordance with claim 1 wherein
said forward force-imparting means includes rotating means for
bearing against the top surface of the uppermost sheet lifted from
said stack and for moving said uppermost sheet in the forward
direction.
4. An automatic feed mechanism in accordance with claim 3 wherein
said reverse force-imparting means includes rotating means disposed
in a position forward of the forwardmost edges of the sheets in
said stack and below said forward force-imparting means, said
reverse force-imparting means rotating in the same direction as
said forward force-imparting means and bearing against the lower
surface of the lowest sheet in any group of sheets moving in the
forward direction.
5. An automatic feed mechanism in accordance with claim 4 further
including a single motor for energizing said lifting means, for
driving said forward force-imparting means and for driving said
reverse force-imparting means.
6. An automatic feed mechanism in accordance with claim 2 wherein
said forward force-imparting means includes rotating means for
bearing against the top surface of the uppermost sheet lifted from
said stack and for moving said uppermost sheet in the forward
direction, and said reverse force-imparting means includes rotating
means disposed in a position forward of the forwardmost edges of
the sheets in said stack and below said forward force-imparting
means, said reverse force-imparting means rotating in the same
direction as said forward force-imparting means and bearing against
the lower surface of the lowest sheet in any group of sheets moving
in the forward direction.
7. An automatic feed mechanism in accordance with claim 6 wherein
said forward force-imparting means includes a plurality of rotating
belts and said reverse force-imparting means includes a plurality
of stripper wheels.
8. An automatic feed mechanism in accordance with claim 6 further
including guide means for forcing the leading edge of the uppermost
sheet in any group of sheets moving in the forward direction to be
directed down toward and out of the bottom of the mechanism.
9. An automatic feed mechanism in accordance with claim 8 wherein
said lifting means further include means for creating an increased
air pressure above the uppermost sheet in a group of sheets moving
in the forward direction at a position forward of the forward edges
of the sheets in said stack for arching the uppermost sheet lifted
by said lifting means.
10. An automatic feed mechanism for feeding individual sheets in
succession from a vertically disposed stack of substantially
horizontal sheets comprising means for imparting a force in the
forward direction to the uppermost of one of the sheets in said
stack, and positive means for imparting a force in the reverse
direction to the lowermost sheet in any group of sheets which are
moving in the forward direction, said reverse force-imparting means
being operative to force said lowermost sheet back into said stack,
the force imparted in said reverse direction being greater than the
normal friction force between two adjacent sheets moving in the
forward direction and being less than the force imparted in the
forward direction to said uppermost sheet.
11. An automatic feed mechanism in accordance with claim 10 wherein
said forward force-imparting means includes rotating means for
bearing against the top surface of the uppermost sheet in said
stack and for moving said uppermost sheet in the forward direction,
and said reverse force-imparting means includes rotating means
disposed in a position forward of the forwardmost edges of the
sheets in said stack and below said forward force-imparting means,
said reverse force-imparting means rotating in the same direction
as said forward force-imparting means and bearing against the lower
surface of the lowest sheet in any group of sheets moving in the
forward direction.
12. An automatic feed mechanism in accordance with claim 11 wherein
said forward force-imparting means includes a plurality of rotating
belts and said reverse force-imparting means includes a plurality
of stripper wheels.
13. An automatic feed mechanism for feeding individual sheets in
succession from a vertically disposed stack of substantially
horizontal sheets comprising blower means for lifting the uppermost
sheet in said stack, transport means disposed above the uppermost
sheet in said stack, means for rotating said transport means to
move in the forward direction a sheet lifted by said blower means
against said transport means, and stripper means disposed in a
position forward of the forward edges of the sheets in said stack
and below said transport means for bearing against the lower
surface of the lowest sheet in any group of sheets moving in the
forward direction.
14. An automatic feed mechanism in accordance with claim 13 wherein
said transport means includes a plurality of belts and further
including means for rotating said stripper means in the same
direction as said transport means.
15. An automatic feed mechanism in accordance with claim 14 further
including a single motor for driving said blower means, said
transport means and said stripper means.
16. An automatic feed mechanism for feeding individual sheets
substantially horizontally and in succession from a stack of sheets
comprising a tray for supporting said stack in position for the
individual feeding of the uppermost sheet in succession from the
top of said stack, a conveyor disposed above said tray and
including at least a lower and substantially horizontal run spaced
above said stack, means for driving said conveyor such that
successive uppermost sheets when lifted into frictional contact
with said lower run are fed by a feeding force in a forward
direction, means for creating a decreased air pressure above said
tray such that successive uppermost sheets in said stack are lifted
against the force of gravity into frictional contact with said
lower run of said conveyor for feed in said forward direction and
positive means for imparting a separating force in the reverse
direction to the lowermost sheet in any group of sheets which may
have been inadvertently lifted from said stack and moved in said
forward direction, said departing force being greater than the
normal frictional force between two adjacent sheets and being less
than said feeding force imparted in said forward direction to
successive uppermost sheets.
17. An automatic feed mechanism according to claim 16 wherein the
means for creating a decreased air pressure includes an air blower
having at least one air inlet duct disposed within the width of
said tray and conveyor, said air inlet duct being spaced from the
forward end of said conveyor and terminating above said lower run
of said conveyor.
18. An automatic feed mechanism according to claim 17 wherein said
air blower has an air outlet duct disposed within the width of said
tray and conveyor, said air outlet duct extending toward said
forward end of said conveyor and being arranged to create a
downward airflow for deflecting successive uppermost sheets moving
in said forward direction.
19. An automatic feed mechanism according to claim 16 wherein the
means for creating a decreased air pressure includes a plurality of
air blowers having a corresponding plurality of air inlet ducts
disposed at spaced locations across the width of said tray and
conveyor, said air inlet ducts being spaced from the forward end of
said conveyor and terminating in a common horizontal plane above
said lower run of said conveyor.
20. An automatic feed mechanism according to claim 17 wherein said
plurality of air blowers have a corresponding plurality of air
outlet ducts disposed at spaced locations across the width of said
tray and conveyor, said air outlet ducts extending toward said
forward end of said conveyor and being arranged to create downward
airflows for deflecting successive uppermost sheets moving in said
forward direction.
21. An automatic feed mechanism according to claim 16 wherein the
means for imparting said separating force includes a plurality of
stripper rollers disposed at spaced locations across the width of
said tray contiguous to and spaced forwardly thereof, said stripper
rollers being spaced from and below said lower run of said conveyor
and dimensioned to engage the lowermost sheet in any group of
sheets which may have been lifted from said stack.
Description
This invention relates to copying machines and more particularly to
a mechanism for automatically feeding original documents of which
copies are required.
In conventional copying machines, those of the electrostatic type,
for example, there is generally provided a supply of copy paper.
Each time a copy of an original document is to be made, a copy
sheet is automatically fed to an exposure station. (In some cases
the copy sheet is cut from a roll, while in others it is fed from a
stack of sheets.) The original documents themselves from which the
copies are made are not generally fed into the machine
automatically. Instead, an operator is required to either place
each original document face down on a glass plate, or to feed each
original document into a pair of input rollers in the original
transport section of the machine. Either of these procedures
requires the continued participation of the operator during the
copying sequence.
It is the general object of this invention to automatically feed
one original document after another from a stack of original
documents into a copying machine, without the required
participation or presence of an operator.
Briefly, in the illustrative embodiment of the invention, the
uppermost original document in a stack of originals is lifted
slightly by means of suction. Rubber (or other friction) belts are
provided for limiting the upward movement of the original document
as it is raised. These belts rotate in a direction to move the
lifted original document toward the input rollers in the original
transport section of the copying machine.
While this arrangement ensures that the upper sheet in the stack
moves into the input section of the copying machine, it has been
found that the sheet or sheets immediately below the uppermost
sheet also sometimes are fed into the original transport section of
the copying machine along with the uppermost sheet. This can arise
as a result of the various originals sticking together, or the
airflow which forces the uppermost sheet against the rubber belts
also forcing additional sheets in the same direction.
In accordance with the principles of the invention, a series of
stripper wheels is provided below and toward the front of the
rubber belts. The stripper wheels rotate in the same direction as
that of the belts, but because they are below the original sheets
rather than above them, any sheet which passes over them is forced
back into the stack. Suppose, for example, that two sheets rise
from the stack and are moved forward by the rubber belts, the lower
sheet moving forward because it is sticking to the upper sheet. As
the two sheets approach the stripper wheels, the stripper wheels
bear against the lowermost sheet and force it back into the stack.
The only force opposing that of the stripper wheels on the
lowermost sheet is the frictional force between the two sheets,
which force is insufficient to maintain the lowermost sheet in step
with the uppermost sheet in opposition to the stripper wheels. In
the case of a single sheet, however, the force moving it in the
forward direction arises from the movement of the rubber belts.
This force is greater than that applied by the stripper wheels in
the reverse direction. Consequently, the uppermost sheet in the
stack, the only one bearing against the rubber belts, is moved out
of the original feed mechanism by the rubber belts toward the
original transport section of the copying machine even though such
movement is opposed by the stripper wheels.
It is a feature of the invention, in the illustrative embodiment
thereof, to provide a source of suction for lifting the uppermost
sheet in a stack, a conveyor mechanism for moving the lifted sheet
in a forward direction, and a mechanism disposed underneath the
forward path of movement of the sheet for forcing additional sheets
below the uppermost sheet to be forced back into the stack.
Further objects, features and advantages of the invention will
become apparent upon consideration of the following detailed
description in conjunction with the drawing, in which:
FIG. 1 is a side view of a typical copying machine 10 with which
the original feed mechanism of the invention can be employed, the
original feed mechanism 20 being shown on top of the copying
machine;
FIG. 2 is a sectional view, shown partly broken away, taken along
the line 2--2 of FIG. 1;
FIG. 3 is an enlarged front view, shown partly broken away, of
original feed mechanism 20 and shows the drive elements
thereof;
FIG. 4 is a top view of feed mechanism 20 with the cover removed;
and
FIG. 5 is a sectional view taken along the line 5--5 of FIG. 4.
FIG. 1 shows an illustrative copying machine 10 having an original
transport section 12. In the ordinary use of this machine, an
original document 88-1 is fed into guide 14, a pair of rollers (not
shown) in the original transport section then moving the original
document through the machine to an output tray (not shown). The
details of the operation of the copying machine itself are
unimportant as far as the present invention is concerned. The
present invention concerns feed mechanism 20. The feed mechanism
includes a tray 74 for holding a stack of original documents to be
copied between two sideplates 92. The feed mechanism serves to
continuously supply one sheet after another at the opening of guide
14 of the copying machine. The feed mechanism 20 simply sits on the
copying machine as shown most clearly in FIG. 2. It is to be
understood that the feed mechanism can be used for purposes other
than the automatic feeding of original documents into a copying
machine. It can be used wherever a continuous feed of sheets from a
stack is required.
The invention is perhaps most clearly understood with reference to
FIG. 5. Four blowers 26-1 through 26-4 are provided for directing
airflow as shown by arrows 78. The four blowers are distributed
across the width of the stack of sheets 88 and serve to lift the
uppermost sheet 88-1. Disposed beneath the blowers is a series of
rubber belts 64 (see also FIG. 2) and as the uppermost sheet in the
stack is pulled up it strikes against the lower parts of the belts.
The belts move in the counterclockwise direction in FIG. 5 and as
the uppermost sheet in the stack bears against them it is forced to
move in the forward direction. The forward edge of the sheet hits a
grid network composed of rods 66 and 70, and is deflected downward
toward guide 14. It should be noted that the airflow is directed
out of the outlet ducts of the blowers in such a way that the
uppermost sheet is forced downward toward the front of the feed
mechanism. This causes the document to arch slightly to further aid
its lifting up toward the rubber belts.
It is possible that one or more sheets directly below the uppermost
sheet 88-1 in the stack will also be forced upward by the flow of
air, and as a result of the friction between the various sheets
might move in the forward direction along with the uppermost sheet.
To prevent this double-feed, stripper wheels 84 are provided. These
stripper wheels also rotate in the counterclockwise direction as
shown in FIG. 5. Each stripper wheel includes a tip 86 preferably
made of a material having a high coefficient of friction, e.g., a
urethane compound. Each tip is mounted on a foam head 94 for
compliance with the original documents. As the stripper wheels
rotate, the friction tips bear against the underside of the
lowermost sheet 88-2 on top of the stripper wheels, and they force
this sheet back into the stack. The force tending to move sheet
88-2 in the forward direction is the frictional force between
sheets 88-1 and 88-2, and this force is less than the frictional
force generated by the rotating stripper wheels. In the event only
one sheet is lifted from the stack, the forward moving force
generated by the friction of belts 64 against the upper surface of
the sheet is greater than the force in the reverse direction
generated by the stripper wheels, and the sheet continues to move
in the forward direction.
As soon as one sheet is fed out of the feed mechanism, the next
sheet is lifted by the airflow. A continuous succession of sheets
is fed into the entrance slot defined by guide 14.
Referring to FIGS. 2-5, motor 32 drives shaft 24. Shaft 24 is
connected at one end to shaft 38 by coupler 36. Shaft 38 is
extended through the various blowers for driving the blower rotors
and vanes 76 as is known in the art. Shaft 24, on the other side of
the motor, is connected to pulley 72 (see FIG. 3) around which belt
46 passes. This belt drives pulley 44 which is mounted on shaft 48.
Gear 50, also mounted on shaft 48, is thus driven by the motor.
Gear 50 drives gear 52 which directly drives shaft 60. A series of
belt drive elements 62 is mounted on shaft 60 and these elements
are driven in the counterclockwise direction of FIG. 5. A second
shaft 28 is provided on which another series of belt drive elements
62 is mounted. The six belts 64 are mounted around the various
pairs of belt drive elements and are driven by shaft 60 in the
counterclockwise direction of FIG. 5.
A second belt 56 couples pulley 54, connected to gear 52, to pulley
58. This pulley is in turn connected to shaft 68 on which the two
stripper wheels 84 are mounted. The stripper wheels are thus driven
in the same direction as the rubber belts, counterclockwise in FIG.
5. But because the sheets pass between the rubber belts and the
stripper wheels, the belts and wheels apply oppositely directed
forces to the sheets.
The overall drive unit is mounted in section 42 of the feed
mechanism. This section is mounted on the leftmost side of the unit
as shown in FIG. 2. The two sides of the base section 22-1, 22-2
have a configuration to mate with the upper surface of copying
machine 10. A grid comprising horizontal rods 66 and vertically
inclined rods 70, seen most clearly in FIGS. 2 and 5, form an upper
guide for the forward moving sheet. Another series of horizontal
rods 82 and a series of bent rods 74 form another grid which serves
both as a lower guide for the forward moving sheet and as a forward
stop for the entire stack of sheets in the feed mechanism, as seen
most clearly in FIG. 5.
Extended across the width of the mechanism are two rods 25, 34 (see
FIG. 4) both of which serve to mount the four blowers 26-1 through
26-4. Each blower is provided with a pair of mounting holes at both
its front and back through which rods 25 and 34 pass, as seen most
clearly in FIG. 5. Separating the blowers on the rods are a series
of spacers 30. The details of the mounting of the blowers in the
unit will be well understood by those skilled in the art. The
blowers are positioned above the rubber belts 64 and serve to suck
up air and force it out as shown by arrows 78 in FIG. 5.
As seen most clearly on FIG. 4, the bottom plate 74 of the unit, on
which the stack of original documents is placed, is provided with a
series of grooves 90 on either side. Into one groove on each side
of the unit an upright guide 92 can be placed to correctly position
the stack of paper documents on tray 74. The side guides are placed
in selected ones of grooves 90 in accordance with the width of the
paper in the stack. Grooves 90 in base plate 74 are designed to
accommodate most common paper sizes. (Only two grooves on each side
of the unit are shown in FIG. 4 for the sake of clarity; it is to
be understood that in practice as many grooves can be used as is
desired.)
Feed mechanism 20 preferably operates at a rate slightly slower
than that of the copying machine, that is, whenever an original
document to be copied is provided by the feed mechanism the copying
machine is in a condition to accept it. Since the feed mechanism
cannot drive a sheet after its trailing edge has left belts 64, the
original transport section of the copying machine should have
control of the sheet by this time.
It should also be noted that anything blocking a paper sheet as it
leaves feed mechanism 20 will not cause a jam. The sheet will
simply slip on the rubber belts.
As described above, the uppermost sheet is lifted by air flowing
into the blower intake parts. This lifting operation is aided by
the turbulence created by the air leaving the blower exhaust ports
in the vicinity of the forward edges of the original stacked
documents. The turbulence helps to separate the originals so that
the uppermost document is the only one which is lifted. With the
uppermost sheet bearing against belts 64 and moving forward, the
exhaust ports are blocked from creating the air turbulence at the
front of the stack of originals to prevent another sheet from being
lifted. In fact, a second sheet may not be lifted until after a
first one has cleared the exhaust ports and this prevents one sheet
from immediately following the other.
Although the invention has been described with reference to a
particular embodiment, and is to be understood that this embodiment
is merely illustrative of the application of the principles of the
invention. It is possible, for example, to create the air
turbulence for lifting the topmost sheet with the use of blowers
situated at the bottom of the unit for blowing air upward. Placing
the (suction) blowers at the top is preferable, however, because,
in the case of blockage of a sheet, the sheet tends to cut off the
airflow to effectively halt the entire operation. Thus, it is to be
understood that numerous modifications may be made in the
illustrative embodiment of the invention and other arrangements may
be devised without departing from the spirit and scope of the
invention.
* * * * *