U.S. patent number 3,771,783 [Application Number 05/227,847] was granted by the patent office on 1973-11-13 for mechanism for feeding, separating and stacking sheets.
This patent grant is currently assigned to Pennsylvania Research Associates, Inc.. Invention is credited to George P. McInerny.
United States Patent |
3,771,783 |
McInerny |
November 13, 1973 |
MECHANISM FOR FEEDING, SEPARATING AND STACKING SHEETS
Abstract
A sheet hopper had multi-angled bottom portions and an angled
front side. A segmented wheel protrudes into the bottom portion to
separate the lowermost sheet and feeds the sheet to gripper rollers
outside the hopper. The hopper angles are such so as to relieve the
bottom portion of the full weight or pressure from the stock.
Inventors: |
McInerny; George P. (Andalusia,
PA) |
Assignee: |
Pennsylvania Research Associates,
Inc. (Philadelphia, PA)
|
Family
ID: |
22854714 |
Appl.
No.: |
05/227,847 |
Filed: |
February 22, 1972 |
Current U.S.
Class: |
271/125;
271/122 |
Current CPC
Class: |
G06K
13/16 (20130101); B65H 3/46 (20130101); B65H
29/70 (20130101); B41F 31/08 (20130101); B65H
1/06 (20130101); B05C 1/04 (20130101); G06M
7/06 (20130101); B65H 3/5284 (20130101); B65H
3/063 (20130101); B65H 3/62 (20130101); B65H
2701/1912 (20130101) |
Current International
Class: |
B65H
1/06 (20060101); B65H 3/46 (20060101); B65H
3/62 (20060101); B65H 3/52 (20060101); B65H
3/06 (20060101); B65H 29/70 (20060101); B65H
3/60 (20060101); G06M 7/06 (20060101); G06M
7/00 (20060101); G06K 13/16 (20060101); G06K
13/02 (20060101); B65h 001/06 () |
Field of
Search: |
;271/10,37,41 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Sroka; Edward A.
Claims
The embodiments of the invention in which an exclusive privilege or
property is claimed are defined as follows:
1. Apparatus for feeding sheets arranged in a stack in a
predetermined direction, which sheets are intermixed in said stack
and may be of different sizes, shapes, thicknesses, finishes and
quality of condition, said apparatus comprising an infeed
hopper;
said hopper including first and second plate means for supporting
said stack, and an outfeed opening defined by adjacent ends of said
first and second plate means;
said first plate means engaging the first sheet to be feed from
said stack and said second plate means engaging the leading edges
of at least some of the sheets in said stack, wherein the leading
edges of said sheets are those edges which first pass out of said
hopper when moving in said predetermined direction;
said first plate means having a first surface portion whose
downstream end lies adjacent said outfeed opening and whose
upstream end is remote from said outfeed opening, and a second
inclined surface portion having a downstream end joined to the
upstream end of said first furface portion with the junction
defining an angle of greater than 90.degree., and an upstream end
remote from said first surface portion, wherein the upstream end of
said second surface portion remote from said junction lies a spaced
distance from the plate of said first surface portion;
the upstream end of said first plate means second surface portion
engaging the trailing edges of the sheets near the bottom of said
stack as the sheets are fed through the outfeed opening whereby
these sheets are relieved of the weight of the rearward end of the
stack;
said second plate means having an inclined supporting surface
aligned at an angle relative to an imaginary vertical line to
remove a substantial portion of the weight of the stack from the
forward ends of the bottom-most sheets;
the end of said second plate means adjacent said first plate means
lying a spaced distance from the downstream end of said first plate
means first surface portion to define a narrow outfeed passageway
therebetween;
said first support plate first surface portion having an
opening;
advancing means protruding through said opening for advancing at
least that sheet in said stack engaging said first plate means
toward said outfeed opening and for simultaneously moving the
trailing edge downstream along said first and second surface
portions and away from the remainder of said stack so as to remove
the rearward weight of said stack from said sheet engaging the
first plate means to facilitate movement of said sheet through said
outfeed passageway.
2. The apparatus of claim 1 wherein said advancing means is
comprised of a rotating member whose periphery is provided with a
raised surface portion for simultaneously jogging at least the
bottom portion of said stack and for advancing at least the bottom
sheet of said stack when said raised surface portion enters said
opening.
3. The apparatus of claim 2 wherein said member is comprised of an
annular shaped roller rotatable substantially about its central
axis; said raised surface portion being formed of a material having
a durometer which is greater than the durometer of the remainder of
said periphery.
4. The apparatus of claim 2 wherein said member is comprised of an
annular shaped roller rotatable substantially about its central
axis; said raised surface portion being formed of a material having
a coefficient of friction which is greater than the coefficient of
friction of the remainder of said periphery.
5. The apparatus of claim 4 wherein the circumferential length of
said raised portion is selected so that the leading edge of said
sheet being fed by said raised portion passes through the outfeed
opening before being disengaged from the surface of said raised
portion.
6. The apparatus of claim 1 wherein at least one portion of the
surface of said second supporting means is provided with means
adapted to increase the sliding friction between said one surface
portion and the leading edges of said stack of sheets as said
sheets move generally downwardly to reduce the amount of weight
imposed upon the bottom sheet in said stack by the remainder of
said stack.
7. The apparatus of claim 6 wherein said one surface portion is
roughened.
8. The apparatus of claim 6 wherein said one surface portion is
corrugated.
9. The apparatus of claim 6 wherein said one surface portion has a
step-like contour.
10. The apparatus of claim 6 wherein said one surface portion has a
saw-toothed surface contour.
11. The apparatus of claim 6 wherein said raised surface portion
repeatedly urges said stack upwardly each time said raised surface
portion enters said opening to urge the leading edges of said
sheets upwardly and against said second supporting means one
surface portion to assure release of the weight of said leading
edges of said stack from the bottom sheet.
12. The apparatus of claim 6 wherein the circumference of said
roller is preferably greater than the length of the shortest
document processed by said apparatus with the said length being in
the feed direction.
13. The apparatus of claim 1 further comprising means loosely
suspended from said second supporting plate and positioned adjacent
said outfeed passageway for preventing said sheets in passing
through said passageway in a skewed manner.
14. The apparatus of claim 1 further comprising drive rollers
positioned adjacent to and downstream of said outfeed opening;
stripper rollers positioned adjacent to said drive rollers;
means for rotating said drive and stripper rollers in opposite
directions;
said drive and stripper rollers being positioned to receive sheets
delivered through said outfeed opening by said advancing means for
separating said sheets and feeding the sheets, one at a time,
toward a stacking location.
15. The apparatus of claim 14 wherein said first plate means
further comprises a third surface portion extending downstream of
said outfeed opening said third surface portion having an
opening;
said drive rollers protruding through said opening;
said first and third surface portions being joined to one another
adjacent said outfeed opening by a short inclined surface
positioned therebetween and forming a continuous surface between
the first and third surface portions to cause the leading edge of
sheets approaching the outfeed opening to droop downwardly to
facilitate their engagement with the drive rollers.
16. Apparatus for advancing sheets from a stack to an outfeed
location whereby said sheets are delivered to said outfeed location
in sequential fashion whereby the trailing edge of the sheet last
advanced to the outfeed location is separated from the leading edge
of the next sheet to be delivered to said outfeed location by at
least a small distance, said apparatus comprising:
an infeed hopper for supporting a plurality of sheets generally
arranged in a stack;
said hopper having an outfeed passageway at one end thereof through
which at least the bottom sheet may pass;
the base of said hopper having an opening;
means protruding at least partially through said opening for
intermittently advancing at least the bottom sheet of said stack
toward said outfeed passageway;
continuously rotating drive means positioned adjacent said
passageway for slidably engaging the bottom sheet in said stack and
advancing at least the bottom sheet or bottom-most sheets fed
thereto toward said outfeed location;
continuously rotating stripper means positioned adjacent said
outfeed passageway and said drive means and rotating in a direction
opposite said drive means for permitting only a single sheet
passing between said stripper means and said drive means to be
advanced toward said outfeed location;
said stripper means and said drive means being adapted to
cooperatively cause the sheet or sheets fed therebetween to assume
an undulating shape in a direction transverse to the forward feed
direction of said sheets to stiffen said sheet or sheets and
thereby facilitate the respective driving and stripping functions
of said driving means and stripping means whereby only the sheet
fed toward said outfeed location is the sheet which makes sliding
engagement with said drive means and regardless of that fact, that
only a single sheet may pass between said drive means and stripper
means.
17. The apparatus of claim 16 wherein said drive means and said
stripper means each include at least one annular shaped roller,
said rollers having surfaces along their annular peripheries of
differing coefficients of friction with the coefficient of friction
of said drive means roller being greater than the coefficient of
friction of said stripper means roller;
said rollers being offset relative to one another in a direction
transverse to the feed direction and the distance between the
centers of rotation of said rollers being separated by a distance
which is less than the sum of their respective radii.
18. The apparatus of claim 17 wherein the near edges of said
rollers which are closest to one another are closely spaced to
pinch the sheet or sheets passing through said drive means and
stripper means between said closely spaced peripheral edges.
19. The apparatus of claim 17 wherein each of said drive and
stripper rollers are respectively mounted upon drive and stripper
shafts;
said rollers being adjustably positioned along their associated
shafts to accommodate sheets of varying thicknesses and to allow
for adjustment of said rollers to compensate for normal wearing
thereof.
20. The apparatus of claim 17 wherein the stripper means comprises
means for pivotally mounting the stripper roller;
the angle of said mounting means and an horizontal plane being
chosen to prevent bouncing of said stripper wheels and prevent
wedging of sheets between said stripper and drive rollers.
21. The apparatus of claim 17 wherein the stripper means comprises
means for pivotally mounting said stripper roller;
said drive and stripper rollers being respectively mounted upon
drive and stripper shafts;
said stripper roller mounting being adapted to support said
stripper shaft;
stripper and drive pulleys being respectively mounted upon said
stripper and drive shafts;
means for rotating one of said shafts;
resilient belt means being entrained about said drive and stripper
pulleys for imparting rotation to the remaining one of said shafts
and for urging said shafts toward one another.
22. The apparatus of claim 16 wherein said drive means is
positioned to make sliding engagement with the first sheet advanced
thereto from said stack before said stripper means makes sliding
engagement with said first sheet regardless of whether one or more
sheets of said stack are advanced toward said stripper means and
drive means.
23. The apparatus of claim 16 where at least the peripheral
portions of said drive means roller and said stripper means roller
are made of materials of differing durometer with the durometer of
said drive means roller material being greater than the durometer
of the remaining roller.
24. The apparatus of claim 16 wherein the stripper means roller is
provided with a convex periphery which is curved in a direction
lateral to the movement of said sheets.
25. The apparatus of claim 16 wherein the drive means roller is
provided with a convex periphery which is curved in a direction
lateral to the movement of said sheets.
26. The apparatus of claim 16 including means for pivotally
suspending said stripper means roller, said suspending means being
adapted to bias said stripper means roller toward said drive
means.
27. The apparatus of claim 16 further comprising accelerating means
positioned between said drive means and said outfeed location and
including continuously rotating cooperating rollers for receiving a
sheet delivered thereto by said drive means and advancing the sheet
toward said outfeed location at an increased velocity.
28. The apparatus of claim 27 wherein the accelerating means is
preferably positioned at a predetermined distance from said drive
means, wherein said predetermined distance is less than the length
of the shortest document accepted by said apparatus, with said
length being measured in the direction of movement, to cause
engagement between a sheet delivered from said drive means and said
accelerating means cooperating rollers before said sheet is
disengaged by said drive means.
29. The apparatus of claim 27 wherein one of said cooperating
rollers is an idler roller;
means for rotating the remaining cooperating roller at a rotational
speed greater than the rotational speed of said drive means
roller.
30. The apparatus of claim 27 further comprising single power drive
means;
means coupled between said power drive means and said accelerating
means for rotating said accelerating means;
clutch means coupled between said accelerating means and said drive
means for selectively rotating said drive means when said clutch
means is engaged;
means coupling said drive means to said stripper means for rotating
said stripper means when said clutch means is engaged.
31. The apparatus of claim 30 further comprising brake means
coupled to said stripper means and being energized to brake said
stripper means and said drive means when said clutch means is
disengaged.
32. The apparatus of claim 31 further comprising means for sensing
the gap between the trailing edge of a document being advanced by
said acceleration means and the leading edge of the next document
being advanced toward said acceleration means for generating a
pulse;
means for counting said pulses;
settable means coupled to said counter for disengaging said clutch
and energizing said brake means when said count advances to the
setting (n) of said settable means to slow the movement of the
(n+1) document toward said acceleration means while permitting the
nth document to reach said outfeed location.
33. The apparatus of claim 31 further comprising means for sensing
the gap between the trailing edge of a document being advanced by
said acceleration means and leading edge of the next document being
advanced toward said acceleration means for generating a pulse;
means for counting said pulses;
settable means coupled to said counter for engaging said clutch and
energizing said brake means when said counter advances to one less
(n-1) than the setting (n) of said settable means to slow the
movement of the (n+1) document toward said acceleration means while
permitting the nth document to reach said stacker;
gate means positioned between said acceleration means and said
outfeed location, said gate means comprising a pivotally mounted
gate having a first position for preventing sheets advanced toward
said gate means from being deflected toward said outfeed location
and a second position for permitting sheets advanced toward said
gate means to be deflected toward said outfeed location;
said gate means including relay means coupled between said gate and
said settable means for moving said gate to said second position
after said pulse representing the (n-1)th document is generated,
and for moving said gate to said first position after the pulse
representing the nth document is generated;
said settable means including means for deenergizing said brake and
disengaging said clutch a predetermined time delay after said relay
means has operated said gate to said second position;
said relay means being adapted to return said gate means to said
first position after said counting means generates a pulse
representing the nth document.
34. The apparatus of claim 16 further comprising deflecting means
positioned between said drive means and said outfeed location for
substantially simultaneously deflecting each sheet leaving said
drive means toward said outfeed location and for preventing said
sheets striking said deflection means from moving toward said
outfeed location in a skewed manner.
35. The apparatus of claim 16 wherein drive means comprise at least
one drive roller having an annular groove around its periphery;
said stripper means comprising at least one roller having a curved
periphery and being positioned at least partially within the groove
formed in said drive roller whereby the distance between the
centers of said drive and stripper rollers is less than the sum of
the outer radii of said drive and stripper rollers.
36. The apparatus of claim 16 wherein drive means comprise at least
one drive roller having a plurality of annular grooves around its
periphery;
said stripper means comprising at least two roller having curved
peripheries separated by a central gap, each of said peripheries
being positioned at least partially within associated grooves of
said drive roller whereby the distance between the centers of said
drive and stripper rollers is less than the sum of the outer radii
of said drive and stripper rollers.
37. Apparatus for feeding sheets in a forward feed direction from
an infeed to an outfeed location on a single sheet basis
comprising:
feed means for advancing sheets from said infeed toward said
outfeed locations in said forward feed direction as said sheets
engage said feed means;
stripper means and drive means positioned between said infeed and
outfeed locations and adjacent said feed means; said stripper and
drive means cooperating to constrain sheets to pass therebetween
whereby opposite surfaces of the sheets fed therebetween are
engaged by said drive and stripper means;
said drive and stripper means each having rollers arranged in
staggered fashion, the peripheries of the stripper rollers
extending between the peripheries of the feed rollers to cause said
sheets fed therebetween to assume an undulating configuration for
stiffening said sheets as they pass through said drive means and
stripper means;
means for rotating said stripper means rollers and said drive means
rollers in opposite directions to cause said stripper means rollers
to tend to urge sheets in the reverse direction;
the peripheral surfaces of said drive means rollers having a higher
coefficient of friction than those of the stripper means rollers to
cause single sheets passing between said drive and stripper means
to be fed in the forward feed direction while multiple sheets
passing between said drive and stripper means are caused to be
stripped by said stripper means to cause the sheets between the
drive and stripper means to be advanced to said outfeed location in
the order of their relative position to the feed means with the
sheet first engaging the feed means being the first to be advanced
to the outfeed location.
38. The apparatus of claim 37 wherein said stripper means is
further comprised of a swingeable support means pivoted at a first
end thereof and having means at the opposite end for rotatably
mounting said stripper means rollers to enable said stripper means
rollers to "float" relative to said drive means.
39. The apparatus of claim 38 wherein said drive means further
comprises means for driving said stripper means rollers without
interfering with the "floating" mounting of said stripper means
rollers.
40. The apparatus of claim 39 wherein both the pivot point and
center of rotation of said stripper means rollers are located to
one side of the plane of movement of said sheets to eliminate
"bouncing" of said stripper means rollers.
41. The apparatus of claim 40 wherein the support means is aligned
relative to the plane of movement of the sheets so that an
imaginary straight line between said pivot point and the center of
rotation of said stripper means rollers forms an angle of greater
than 0.degree. and less than 90.degree. with the plane of movement
of said sheets.
42. The apparatus of claim 37 wherein said stripper and means has
at least two rollers;
said rollers being positioned so that the near edges of adjacent
drive and stripper means rollers pinch a sheet as it passes
therebetween so that each sheet is "pinched" in a minimum of two
locations whereby said pinching action promotes the undulated
configuration which a sheet assumes and further facilitates both
the "stripping" and feeding operations.
43. Apparatus for feeding sheets arranged in a stack in a
predetermined direction, which sheets are intermixed in said stack
and may be of different sizes, shapes, thicknesses, finishes and
quality or condition, said apparatus comprising:
means for supporting said stack in an inclined fashion with the
leading edges of each sheet being inclined downwardly and
positioned below their associated trailing edges;
said hopper comprising an inclined bottom plate for supporting said
stack and engaging at least the bottom-most sheet in the stack;
an inclined front plate;
the lower end of said front plate being positioned above said
supporting plate for forming a feed opening therebetween to permit
the passage of sheets therethrough; abovu said opening;
said said front plate engaging the leading edges of those sheets in
the stack positioned above said opening;
said front plate being aligned to form an angle with an imaginary
vertical line to remove at least a portion of the weight of the
stack from those sheets whose leading edges are positioned below
the lower end of said front plate;
the portion of said support plate remote from said opening being
inclined upwardly and away from said opening for supporting the
upstream end of said stack;
said support plate having an opening positioned between said feed
opening and the inclined portion of said support plate;
advancing means protruding through said opening for jostling said
stack and advancing sheets from the bottom of said stack toward
said feed opening;
said support plate inclined portion and advancing means cooperating
to move the trailing edges of the advanced sheets downstream of the
rearward end of the stack so as to be substantially relieved of the
weight of the stack to facilitate feeding of the sheets through
said feed opening.
Description
BACKGROUND OF THE INVENTION
There are a wide variety of applications in which document feeders
and/or separators are either required or are advantageous for use.
For example, in banks or other like institutions, it is very
advantageous to provide apparatus for accurately counting large
stacks of bills (i.e., paper currency). One of the problems
encountered in counting stacks of bills at relatively high rates of
speed resides in the fact that some or many of the bills being
counted may be either slightly or severely mutilated or creased
from folding, hence they require special care and handling or,
alternatively, such damaged or mutilated bills must first be
removed from the stack of like bills due to the fact that present
day feeding and separating devices are incapable of counting such
bills. In addition thereto, bills which may be perfectly intact but
may be either severely folded or creased require special handling
procedures wherein the bills must be carefully and firmly pressed
or smoothed down before being capable of being handled by present
day feeding and counting devices.
Banks and other similar institutions also handle tremendous volumes
of checks which are of varying sizes, thicknesses, finishes and the
like. As a result, stacks of checks of the same dimensions and
thicknesses must be formed before such checks can be counted,
thereby greatly increasing the amount of handling operations
necessary in the processing of such documents.
Another typical application in which such feeding, separating,
counting and stacking devices are employed is in the field of
coupons. Coupons may take a variety of forms such as those which
are printed in newspapers and/or periodicals and which are normally
cut out from such newspapers and periodicals prior to use. Coupons
may also be provided as part of the package in which a product is
wrapped and hence be of still another form of paper insofar as
size, weight and/or thickness of paper and finish are concerned.
Companies processing such coupons would find it highly advantageous
to be able to process coupons of varying sizes, thicknesses and
finishes while at the same time being capable of counting stacks of
such dissimilar coupons accurately and at a high rate of speed. It
should be understood that the applications set forth hereinabove
are merely exemplary and that a large variety of other applications
in which devices capable of separating and counting documents of
dissimilar sizes, weights, thicknesses and finishes can be used to
great advantage.
BRIEF DESCRIPTION OF THE INVENTION
The present invention is characterized by providing a sheet
feeding, separating and stacking device which is simple in design
and yet which is capable of feeding and separating sheets of
different thicknesses, weight, dimensions and finishes while at the
same time being capable of providing a highly accurate count of a
stack of such sheets with the feeding, separation and counting
occurring at speeds not heretofore obtainable through conventional
apparatus. The present invention comprises an infeed hopper for
depositing a large stack of sheets which may be of dissimilar size,
thickness, weight and finish. The operator need not exercise any
special care in forming a stack of such sheets not need the
operator exert any special care as to the manner in which the stack
of sheets is deposited in the hopper, thereby greatly facilitating
the sheet feeding and separating operation.
The infeed hopper is provided with an inclined support having an
opening through which a portion of the periphery of a picker wheel
protrudes. The picker wheel is preferably caused to rotate at a
constant speed and is provided with an eccentric surface along the
portion of its periphery with said eccentric surface having a
higher coefficient of friction than the remaining peripheral
portion of the picker wheel. The picker wheel performs the dual
functions of advancing at least the bottom-most sheet in the stack
of sheets toward the stripping and separating apparatus while at
the same time, due to its eccentric periphery, causing the entire
stack to be jostled or jogged upwardly so as to facilitate
separation of sheets within the stack. The infeed hopper is
provided with a configuration which causes the bottom-most group of
sheets in the stack to be relieved from the weight of or on the
remaining sheets within the stack thereby facilitating separation
of the bottom-most sheets from one another.
The picker wheel advances the bottom-most group of sheets toward
the drive wheel assembly thereby releasing the aforesaid group of
sheets from the weight of the stack at the rearward end of the
stack due to the shape of the rearward portion of the inclined
support. The infeed hopper also includes a second inclined surface
which supports the weight of the forward end of the stack to
further relieve the weight of the stack from the bottom few sheets.
The sheets thus released are then free to slide downwardly along
the support surface to come under the influence of the drive and
stripper assemblies.
The drive wheels are arranged in spaced parallel fashion along a
common shaft and rotated at a substantially constant velocity at
least equal to the rotational speed of the picker wheel.
A stripper wheel is mounted at the free end of a floating stripper
wheel assembly comprised of a pair of arms whose rearward ends are
pivotally mounted within the machine frame and whose free ends
support a shaft upon which the stripper wheel is mounted. The
stripper wheel slidingly engages the document (or documents) fed to
the drive wheel and the stripper wheel mounting automatically
adjusts the position of the stripper wheel relative to the sheet
being fed to the drive wheel so as to automatically compensate for
differences in weight, stiffness, and/or thickness of the sheets
being processed.
The stripper wheel is rotated at a constant rate of speed with the
rotational velocity being in a range which extends from a value
which is less than the rotational velocity of the drive wheel to a
value which is greater than the velocity of the drive wheel. The
stripper wheel is rotated so that the peripheral portion thereof
which engages the sheet (or sheets) being fed to the drive wheels
moves in a direction reverse from that of the forward feed
direction. The stripper wheel is also mounted so as to be
positioned to lie in a gap formed between a pair of spaced drive
wheels whereby the periphery of the stripper wheel is positioned at
a height below the peripheries of the drive wheels between which
the stripper wheel is located. This arrangement causes the sheet
(or sheets) fed to the drive wheel assembly to assume a curved
undulating configuration which stiffens the sheet or sheets to
cause the sheets to undergo lateral movement to thereby greatly
facilitate separation of the sheets in cases where two or more
sheets are fed into the region between the stripper wheel and the
drive wheels. The stiffness imparted to the sheets also enhances
the frictional engagement with the drive and stripper wheels.
The coefficient of friction of the peripheries of the drive wheels
is substantially greater than that of the coefficient of friction
of the periphery of the stripper wheel and preferably the material
from which the stripper wheel is formed is less resilient than the
material from which the drive wheels are formed (i.e., it has a
higher durometer).
The infeed hopper is provided with a surface portion lying
immediately adjacent the region of the drive wheels and stripper
wheels which forms an abrupt incline so as to enable the leading
edge of the bottom sheet to "droop" down and thereby enhance the
frictional engagement between the bottom-most sheet fed toward the
drive wheels by the picker wheel.
The surface of the infeed hopper supporting the leading edge of the
stacked sheets preferably has at least a portion thereof being
formed or otherwise machined to exert an increased frictional force
upon the leading edges of the stacked sheets to remove the weight
of the major portion of the stack from the bottom-most sheets to
permit the group of bottom-most sheets to substantially freely
slide downwardly toward the drive wheels when advanced by the
picker wheel. In the case where a single sheet is fed between a
stripper roller and the drive wheel, the relative differences of
the coefficients of friction between these wheels will cause the
stripper roller to slippingly engage the confronting surface of the
bottom-most sheet with the major influence upon the bottom-most
sheet being the frictional engagement of the drive wheels. The
single sheet will thus be fed toward a plurality of acceleration
wheels which cooperate with free wheeling idler wheels to
accelerate the sheet being fed toward the acceleration wheels which
enters between the acceleration wheels and the idler wheels and is
moved at a faster rate of speed as the sheet comes under the
influence of the acceleration wheels which are rotated at a
substantially constant tangential velocity greater than the
tangential velocity of the drive wheels. The spacing between the
centers of rotation of the drive wheels and the acceleration wheels
is such that the document fed between the acceleration wheels and
the cooperating idler rollers will undergo acceleration before the
next sheet in the stack makes frictional engagement with the drive
wheel. This operation creates a finite gap between the trailing
edge of the sheet being fed between the acceleration wheels and the
idler rollers and the leading edge of the next sheet passing over
the drive wheels.
The acceleration wheels and cooperating idler rollers act to
rapidly advance the single sheet fed therebetween toward a stacker
which is designed to abruptly move the trailing edge of the last
sheet fed thereto out of the path of the leading edge of the next
sheet to be fed thereto and before the next sheet enters into the
stacker region, thereby forming a substantially neat and compact
stack of sheets within the stacker in original sequence.
In the case where more than one sheet enters into the region
between the drive and the stripper wheels, the larger coefficient
of friction of the drive wheels operates to urge the bottom-most
sheet in the forward feed direction toward the acceleration wheels
since the frictional grab between sheets is less than the
frictional grab between the drive wheels and the bottom-most sheet.
The drive wheels and stripper wheel arrangement cause the plural
sheets fed therebetween to assume a curved undulating configuration
which greatly facilitates "stripping" the upper sheet from the
bottom-most sheet due to the separation of the sheets in the region
or regions of the undulations which greatly reduces the frictional
forces between engaging surfaces of the plural sheets. The upper
sheet is then "kicked" back into the infeed hopper.
The jogging action of the picker wheel serves to jar the sheets in
the infeed hopper to enhance the stripping operation and to urge
the leading edges of the sheets upward against the associated
engaging surface of the infeed hopper. The differing coefficients
of friction of the stripper and the drive wheels positively assures
the fact that the bottom-most sheet (of a bottom feed apparatus),
or the top-most sheet (of a top feed apparatus), will be the first
sheet fed from the region of influence of the drive wheels and
stripper wheel toward the acceleration wheels regardless of the
fact that the leading edge of the "next" sheet may be fed to the
drive and stripper wheels before the leading edge of the bottom (or
top)-most sheet. The "floating" stripper wheel mounting enables the
device to accurately feed and strip sheets at a high rate of speed
while at the same time accommodating documents of dissimilar
thicknesses, weights, dimensions and finishes to provide a feeding
and separating mechanism which is highly advantageous for use in
the applications set forth hereinabove, as well as a wide variety
of other applications.
In an alternative embodiment, the "floating" stripper assembly may
be replaced by a fixed stripper wheel assembly in which the
distance the stripper wheel may move in a direction away from
sheets being fed between the stripper and drive wheels is
restrained by resilient spring or drive means for those
applications in which the feed and separation apparatus is adapted
to handle sheets within a narrow range of sheet thickness (such as
just paper currency, for example). Alternatively, the "floating"
stripper wheel assembly may be provided with strap means for
achieving the same objective.
The apparatus is adapted to perform batching operations, collating
operations, and operations in which only selected sheets are fed to
the stacker while, all sheets are counted (i.e., "statistical
sampling"). Clutch and brake means are provided to separate batches
of sheets, each containing a precise preselected number of sheets
wherein the clutch means is provided to selectively disengage the
stripper, drive and picker wheels from the apparatus drive source
while the brake means abruptly halts rotation of the stripper,
drive and picker wheels. The primary drive source for the apparatus
continues to operate until the last sheet of the batch of
preselected count reaches the stacker.
For collating operations, i.e., operations in which it is desired
to count all sheets deposited in the infeed hopper and to separate
every "Nth" (i.e., every second, third, fourth, etc.) sheet from
the remainder of the stack, a gate means is provided to allow
selected sheets to bypass the stacker when leaving the acceleration
wheel when the gate is in a first position while deflecting the
remaining sheets toward the stacker when the gate is in a second
position. The gate is employed for statistical sampling as well as
collating operations.
The clutch and brake assemblies may also be employed in conjunction
with the gate means to enhance the operation of the gate means by
increasing the gap between the "sampled" sheet and the sheets
passing through the feed mechanism immediately before and
immediately after the "sampled" sheet. The clutch and brake
mechanisms act to "slow down" the feed of the "sampled" sheet by
the drive wheels after the sheet preceding the "sampled" sheet is
sensed and to "slow down" the feed of the sheet immediately
following the "sampled" sheet by the drive wheels after the
"sampled" sheet has been sensed to provide sufficient time for the
gate to undergo mechanical movement.
OBJECTS OF THE INVENTION
nturmyxed is therefore one primary object of the present invention
to provide an apparatus for feeding and accurately separating
intermixed documents of dissimilar characteristics at speeds not
heretofore attainable through conventional apparatus.
Still another object of the present invention is to provide
apparatus for feeding and accurately separating sheets of widely
differing thicknesses and characteristics at high speed even though
such sheets may be partially or even severely mutilated.
Still another object of the present invention is to provide a novel
apparatus for feeding and accurately separating sheets of
dissimilar characteristics arranged within a single stack of sheets
wherein the sheets fed thereby are separated one from the other and
wherein feeding of more than one sheet at a time is prevented
through the use of a stripper wheel assembly arranged to cooperate
with a drive wheel assembly to automatically accommodate sheets of
varying thicknesses within the stack and to thereby permit only one
sheet at a time to be advanced from the cooperating drive and
stripper assemblies toward a stacking facility.
Yet another object of the present invention is to provide a novel
apparatus for feeding and accurately separating sheets of
dissimilar characteristics arranged within a single stack of sheets
wherein the sheets fed thereby are separated one from the other and
wherein feeding of more than one sheet at a time is prevented
through the use of a stripper wheel assembly arranged to cooperate
with a drive wheel assembly to automatically accommodate sheets of
varying thicknesses within the stack and to thereby permit only one
sheet at a time to be advanced from the cooperating drive and
stripper assemblies toward a stacking facility and whereby
acceleration means are provided to increase the velocity of the
last sheet fed thereto by the stripper and drive wheel assemblies
to provide a finite gap between sequentially advanced sheets to
thereby enable said sheets to be accurately counted before they are
stacked in an outfeed stacker.
Another object of the present invention is to provide a hopper for
stacking and feeding sheets which is designed to release several of
the bottom-most sheets in the stack from the weight of or on the
remainder of the stack thereby enabling the aforesaid several
sheets to freely slide downwardly along an inclined supporting
surface of the infeed hopper to undergo further processing, such as
a separating and advancing operation.
Still another object of the present invention is to provide a sheet
feeding and separating apparatus including anti-skewing means for
causing sheets being processed by said apparatus to be advanced
through various portions of the apparatus with their leading edges
moving in a nonskewed alignment.
Still another object of the present invention is to provide a
stacker for receiving and stacking sheets in an orderly manner and
in original sequence even though said sheets are advanced toward
the stacker in a high speed and skewed manner.
Still another object of the present invention is to provide feeding
and separating means wherein sheets may be accurately counted and
divided into distinct "batches."
Another object of the invention is to provide feeding and
separating means in which sheets may be accurately counted and
either collated after being counted or in which "statistical
samples" may be extracted from the counted sheets.
BRIEF DESCRIPTION OF THE FIGURES
The above as well as other objects of the present invention will
become apparent when reading the accompanying description and
drawings in which:
FIG. 1 is an elevational view of a feeding, separating and stacking
apparatus designed in accordance with the principles of the present
invention.
FIG. 1a is a sectional view showing a portion of the stacker of
FIG. 1 looking in the direction of arrows 1a--1a.
FIG. 1b is an elevational view showing a portion of the apparatus
of FIG. 1 and incorporating a gate mechanism.
FIG. 1c shows the gate mechanism of FIG. 1a in greater detail and
includes a block diagram of the electronics used to operate the
gate mechanism and associated mechanisms.
FIG. 2 is an elevational view of a portion of arrows 2--2 wherein
only those portions which are felt to be important to clarify an
understanding of the operation of the mechanism have been
illustrated.
FIG. 2a is a perspective view of a portion of the stripper assembly
of FIGS. 1 and 2.
FIG. 2b shows one idler assembly of FIG. 1 in greater detail.
FIG. 3 is an elevational view of a portion of FIG. 2 provided to
explain the manner in which a plurality of sheets entering the
drive and stripper assemblies are separated.
FIGS. 3a and 3b are elevational views showing alternative
arrangements for the drive and stripper wheels of FIGS. 2 and
3.
FIG. 4 is another preferred embodiment of the present invention
showing a top feed input hopper for feeding sheets to the
separating apparatus.
FIGS. 5a-- 5c show various embodiments of the portion of the infeed
hopper employed to support the leading edges of the stacked
sheets.
FIGS. 6A and 6B show an end view and front view, respectively, of
an alternative embodiment of the stripper wheel assembly.
FIGS. 7a-7c are elevational views showing the stripper and feed
wheel drives for explaining the optimal arrangement for the
stripper assembly.
DETAILED DESCRIPTION OF THE FIGURES
FIGS. 1 and 2 show a device 10 designed in accordance with the
principles of the present invention, which device 10 is comprised
of a housing 11 having a base portion 12 for supporting device 10
upon any suitable surface such as, for example, a table or counter.
The relatively small size and light weight of the device greatly
enhances its portability and facilitates handling of the device to
enable its use in practically any desired location.
The housing 11 is provided with a front face 13 at its upper end
which may be fitted or otherwise provided with control panels
incorporating controls (not shown for purposes of simplicity) for
turning the machine on and off, providing a visually observable
count of the number of documents handled by the device and so
forth, with the number and type of display mechanism and controls
being dependent merely upon the needs of the particular
application. 3ys The face 13 forms a portion of the front of
housing 11 which is further provided with an infeed hopper 14 which
consists of a stack supporting member 15 and a forward edge
supporting member 16. A stack of sheets to be fed and separated is
positioned within infeed hopper 14 in the manner shown best in FIG.
1 with a portion of the weight of the stack substantially resting
upon the upper exposed surface of plate 16. The inclination of the
hopper 14 and specifically base plate 15 and supporting plate 16,
as shown best in FIG. 1, is such that the weight of the sheets
within the stack serve to cause the stack to remain within the
hopper without providing any top weight upon the stack. The
right-hand-most portion 15a of the hopper supporting plate 15 is
inclined at an angle greater than that of the adjacent surface
portion 15b to which it is integrally joined. Also the plate
portions 15a and 15b can be seen to define an angle of greater than
90.degree.. The inclined orientation of the entire infeed hopper is
such as to cause the forward or leading edges of at least some of
the sheets in stack S to rest against plate 16. It should, however,
be carefully noted that the nature of the sheet feeding and
separating mechanism is such that no special care need be given to
the preparation of a stack before being placed in the infeed
hopper. For example, there is no need whatsoever to cause all of
the forward edges of the sheets within the stack to be aligned so
as to rest against the exposed surface of plate 16 and, in fact,
some sheets within stack S are shown with their forward edges lying
a spaced distance from the surface 16.
The infeed hopper supporting surfaces 15a and 15b are integrally
joined at a "knee" portion 15c which is located a predetermined
distance D from portion 16a of infeed hopper plate 16. This
distance is preferably selected so as to be substantially less than
the width W of the narrowest document which the infeed hopper is
designed to process. As the sheets of the stack are fed in the
direction of arrow A, a small group of the bottom-most sheets are
displaced or otherwise moved in the direction shown by arrow A so
that their trailing edges are moved downwardly along inclined
portion 15a of the infeed hopper supporting plate 15. The remainder
of the stack S, however, has its rearward portion resting upon the
right-hand end of inclined portion 15a (relative to FIG. 1). This
arrangement removes the weight of or on the rearward end of stack S
from the group of sheets (usually 1-5 in number) removed from
beneath the right-hand end of the stack, thereby greatly
facilitating the feeding and separating operations as will be more
fully described.
A picker wheel 19 is mounted upon a shaft 20 (see FIG. 2). Shaft 20
is journalled at a first end thereof 20a and is also journalled at
a second end thereof 20b. The left-hand end of shaft 20 (relative
to FIG. 2) extends beyond the machine frame F and is fitted with a
pulley 21 rigidly secured to shaft 20 for driving the picker wheel
in a manner to be described.
The portion 15b of supporting plate 15 is provided with an opening
(not shown) to enable the upper portion of the picker wheel 19 to
protrude therethrough. The angle of inclination of surface 16a of
the infeed hopper which engages the leading edges of most of the
sheets is such as to support some of the weight of the sheets and
thereby release this weight from the bottom-most group of sheets to
greatly facilitate the feeding of the sheets from the infeed hopper
to the next processing location. The weight of the sheets may be
represented as a force vector C whose direction is vertically
downward. This force may be represented as the force components
C.sub.1 and C.sub.2 which are, respectively, perpendicular and
parallel to surface 16a. Surface 16a to counteracts to the force
component C.sub.1 and thereby relieves this force component from
the weight of the bottom-most sheets. Additionally, there is some
frictional force between the leading edges of the sheets and the
engaging surface 16a to reduce the effect of the force component
C.sub.2 upon the bottom-most sheets. This frictional force may be
enhanced or increased by treating or otherwise forming the sheet
engaging surface of portion 16a to provide a roughened finish.
Alternatively, the portion 16a may have a corrugated configuration
16a' as shown in FIG. 5a, a step-like configuration 16a' as shown
in FIG. 5b; or a gently curved surface portion 16a'" as shown in
FIG. 5c.
Picker wheel 19 is provided with an insert 19a along a portion of
its periphery which is formed of a material having a substantially
high coefficient of friction and which is raised a finite distance
above the remaining periphery of wheel 19. A suitable driving belt
(shown schematically as dotted line 142 for purposes of simplicity)
is entrained about drive wheel pulley 139 and pulley 21 so as to
rotate picker wheel 19 at a substantially constant angular velocity
whereby wheel 19 rotates in the direction shown by arrow 22. The
raised portion 19a, having a higher coefficient of friction than
the remainder of the periphery of wheel 19, serves the dual
functions of jogging or jarring at least the small group of (five
or six) sheets positioned at the bottom-most portion of stack S so
as to jar the sheets loose from one another to reduce their
frictional engagement while at the same time causing the
bottom-most sheet to be easily "picked up" and accelerated in the
direction shown by arrow B where it is then caused to be fed toward
the stripping and separating mechanisms.
The jogging effect of the picker wheel also serves to urge the
stack upwardly and in a forward direction. This action serves to
move the leading edges upwardly against the surface portion 16a to
"lift" the weight of the forward end of stack S off the bottom-most
sheets and enable the bottom-most sheets to freely slide downwardly
along base member 15 toward the drive wheels.
The picker wheel tangential velocity should preferably be chosen to
cause the insert 19a to engage the largest document processed by
the apparatus only once per revolution with the "critical" sheet
dimension being the length of the document measured in the feed
direction. In cases where the document length (in the "critical"
dimension) is uniform for all sheets being handled, the
circumference of the picker wheel should preferably be slightly
greater than the "critical" length. For example, if the document
"critical" length is 2 inches, the picker wheel circumference
should be about 2 1/8 inches. The picker wheel should also
preferably be designed to have its raised portion 19a in engagement
with the document being fed at least until the leading edge of that
document engages the periphery of the drive wheel. This feature may
be achieved by adjusting the picker wheel circumference and/or
adjusting the length P of the raised portion 19a.
The tangential velocity of the picker wheel is preferably less than
that of the drive wheel so as not to feed documents faster than
they can be handled by the drive wheel.
The bottom-most sheet in the stack is thus urged toward a plurality
of drive wheels 23 which are all mounted upon a common shaft 24
journalled within the machine frame F near its right and left-hand
ends. At least one end of shaft 24 is provided with a pulley 25 for
receiving a belt (not shown for purposes of simplicity) which is
entrained about a suitable drive wheel and pulley 25 to rotate
shaft 24 and hence rollers 23 in the direction shown by arrow 26.
Portion 15e of infeed hopper support plate 15 is integrally joined
to portion 15b of plate 15 in the region of a double bend or "kink"
provided within support plate 15. As can best be seen in FIG. 1,
the forward-most end of support plate portion 15b bends downwardly
at 15e and upwardly at 15f so that plate portion 15d lies a slight
distance below plate portion 15b. Plate portion 15d is further
provided with a plurality of apertures (not shown for purposes of
simplicity) to enable a portion of the periphery of rollers 23 to
protrude therethrough in the manner shown best in FIG. 1. The
centrally located rollers 23a and 23b are positioned in closely
spaced fashion while the spacing between rollers 23 and 23a and 23b
and 23c is substantially greater than the spacing between rollers
23a and 23b. This arrangement is to accommodate the stripper wheel
assembly to be described in more detail hereinbelow.
The "kink" or double bend provided in the immediate region wherein
the peripheries of rollers 23-23c protrude through plate portion
15d serves to facilitate the frictional engagement between the
bottom-most sheet fed toward drive wheels 23 by picker wheel 19 due
to the fact that the leading edge of the bottom-most sheet is
enabled to "droop" downwardly over the kink in the support member
to assure better frictional engagement of the sheet with the
peripheries of rollers 23-23c.
A stripper assembly 30 is positioned substantially above the drive
wheel assembly comprised of drive wheels 23-23c. Assembly 30
consists of a shaft 31 having one end 31a mounted within an
elongated opening in machine Frame F. A nut 31c engages the
threaded end of shaft 31. The elongated opening in the machine
frame receiving shaft end 31a allows for adjustment of the stripper
wheel assembly to assure parallelism with the drive wheel assembly.
The opposite end 31b of shaft 31 fits within an opening in the
machine frame and is secured thereto by a nut 31d.
A stripper wheel depth adjusting member 151 (see FIG. 2a) has an
opening 152 which receives shaft 31 which is press fitted or
alternatively provided with a set screw (not shown) to lock shaft
31 to member 151. An adjusting screw passes through elongated
clearance opening 154 in member 151 and threadedly engages a tapped
opening provided in an inwardly projecting portion F.sub.1 of the
machine frame. A helical spring 156 encircles adjusting screw 153
and has its ends bearing against projection F.sub.1 and the arm
151a of member 151. This assembly (by adjustment of screw 153)
controls the angular orientation of shaft 31 and hence controls the
depth of entry of the stripper wheels between the drive wheels.
Spring 156 acts to prevent screw 153 from moving from the adjusted
position.
A pair of stripper wheel supporting plates 32 and 33 are secured to
one another by means of a cross-arm 34 (shown best in FIG. 2) and
are each provided with openings for receiving bearings 35 and 36
which free wheelingly mount arms 32 and 33 to shaft 31. Assembly 30
further includes a substantially U-shaped member 37 whose arms 37a
and 37b are provided with openings for receiving shaft 31. Set
screws 37c and 37d provided in arms 37a and 37b lock member 37 to
shaft 31 causing member 37 to assume the same angular orientation
as shaft 31. A pulley member 38 is embraced by arms 37a and 37b and
is arranged to rotate in a free wheeling manner upon shaft 31.
Pulley 38 is provided with a pair of continuous annular-shaped rims
38a and 38b. A cylindrical bushing (not shown) is preferably
mounted between pulley 38 and shaft 31 to enhance the free wheeling
movement of the pulley.
Positioned above pulley member 38 and shaft 31 is a shaft 39 having
bearings 40 and 41 near its free ends to mount shaft 39 to machine
frame F in a free wheeling manner. Shaft 39 is provided with a
pulley 42 adapted to receive a belt 140 (shown schematically as a
dotted line for purposes of simplicity) which is entrained about a
drive pulley 138 and pulley 42 so as to rotate shaft 39 in a
direction shown by arrow 43 (see FIG. 1). Shaft 39 is provided with
a pulley 44 rigidly secured to shaft 39 and located at a point
substantially intermediate the ends thereof. A belt 45 is entrained
about pulley 44 and pulley 38 (in the region between rings 38a and
38b) so as to impart rotation of shaft 39 and hence pulley 44 to
pulley 38. For purposes of simplicity, belt 45 has been represented
as a dotted line extending between pulleys 38 and 44 in FIG. 2.
This arrangement causes pulley 38 to rotate in the direction shown
by arrow 46 (see FIG. 1).
Stripper assembly 30 is further comprised of a shaft 47 mounted to
the forward free ends of arms 32 and 33 by means of bearings 48 and
49 which mount shaft 47 in a free-wheeling manner relative to arms
32 and 33. A belt 50 (see FIG. 1) is entrained about the left-hand
portion of pulley 38 and a pulley 51 secured to free-wheeling shaft
47. Belt 50 is shown in dotted line fashion in FIG. 2 for purposes
of simplicity. Belt 50 is fitted between rims 51a and 51b provided
on pulley 51. Free-wheeling shaft 47 is further provided with a
pair of stripper rollers 52 and 53 rigidly secured to shaft 47 and
arranged so that the peripheries of wheels 52 and 53 extend
slightly below the peripheries of drive wheels 23-23c, as shown in
both FIGS. 1 and 2. Thus rotation of shaft 39 and pulley 44 is
ultimately imparted to stripper wheels 52 and 53 which rotate in
the direction shown by arrow 54 (see FIG. 1). The wheels 52 and 53
are laterally adjustable along shaft 47 as are the drive wheels
23-23c along their shaft 24, to adjust the assemblies for
accommodating sheets of different thicknesses and stiffness as well
as providing for periodic adjustment due to the normal wearing of
the wheels.
The stripper wheels supporting arms 32 and 33, being mounted to
common shaft 31 in a free-wheeling manner, enable the stripper
wheels to exert a downward force upon a sheet entering into the
region between drive rollers 23-23c and stripper wheels 52 and 53
whose magnitude is a function of the weights of arms 32 and 33,
shaft 47, bearings 48 and 49, pulley 51 and at least a portion of
belt 50, as well as a cross-arm 55 and the counter balancing effect
of the rearward portion of supporting arms 32 and 33, cross-arms 34
and the rearward portion of U-shaped member 37. The downward force
exerted by the stripper wheel assembly is also a function of the
length L of arms 32 and 33 between shafts 31 and 47, as shown best
in FIG. 2. The force may therefore be altered by using arms 32 and
33 of differing lengths or from the use of arm portions between
shafts 31 and 47 which may be made adjustable.
It should be noted that the downward force exerted by stripper
wheels is totally independent of the rotational driving force
applied to stripper wheels 52 and 53 due to the unique mounting
assembly which enables wheels 52 and 53 to "ride" upon the sheets
passing beneath the wheels and to pivot about shaft 31 totally
independent of the driving force mechanism.
The maximum depth which stripper wheels 52 and 53 may enter between
drive rollers 23-23c is controlled by adjusting member 151 by
adjusting screw 153, which provides a "fine" adjustment
thereof.
The depth to which stripper rollers 52 and 53 may be lowered
between drive wheels 23-23c is further controlled by a set screw
37e (see FIG. 1) which threadedly engages a tapped opening in
member 37 so that its lower end extends toward the upper surface of
cross-arm 34. The rotation of arms 32 and 33 about shaft 31 in the
direction reverse that of arrow 46 is controlled by the adjustment
of screw 37e. Member 37, set screw 37e and bar 34 provide the
"coarse" adjustment for the depth.
If desired, the arms 32 and 33 may be spring loaded to limit the
amount of their movement in the clockwise direction about shaft 31
by means of spring 170 coupled between cross-arm 34 and U-shaped
member 37 by fasteners 37f and 37e, respectively, to reduce the
amount of "free floating" of the stripper wheels.
In applications wherein it is desired to process sheets whose
thicknesses fall within a moderate range, as compared with the
broad range of thicknesses which the stripper is presently designed
to handle, a strap 171 (shown in dotted line fashion) may be
entrained around U-shaped member 37 and cross-arm 34 (in place of
spring 170) to substantially lock the stripper wheels in a position
(relative to said drive wheels) which is optimized for handling
sheets having thickness lying within the aforesaid narrow
range.
FIGS. 6A and 6B show a stripper wheel alternative embodiment 30'
which may be employed in units used to process documents whose
thicknesses fall within a rather moderate range (i.e., from as thin
as paper currency to as thick as punch cards). Only one-half of the
assembly is shown in FIG. 6b, it being understood that the opposite
half of the assembly is the mirror image of the half being
described.
A shaft 172 is journalled within a bearing 173 provided in the
machine frame F. A member 151', substantially identical to member
151 shown in FIG. 2a, is secured to shaft 172 by set screw 174. An
adjusting screw 176 threadedly engages an opening in member 151'
and bears against a fixed projection 177 extending inwardly from
machine frame F. A stripper wheel support arm 178 is fixedly
secured to shaft 172 by set screw 179, and free-wheelingly mounts
stripper wheel shaft 180 thereto. A clearance opening 181 is
provided in frame F to allow for adjustment of shaft 180 to
maintain parallelism between stripper wheels 52-53 and drive wheels
23-23c, by means of the pair of adjusting screws 176.
A shaft 182 secured between the side walls of frame F and
positioned beneath shaft 178 (see FIG. 6A) is fitted with an
adjusting screw 183 which bears against a downwardly extending stop
178a on member 178 to control the amount which the stripper wheels
may be lowered. The ends of rod halves 172 and 172a remote from the
machine frame F are telescoped within a hollow cylindrical tube
172b which acts to keep shafts 172 and 172a substantially in
alignment with an imaginary longitudinal axis A, while at the same
time permitting shafts 172 and 172a to be independently rotated
about axis A by their "fine" adjusting members 151 and 151'.
Shaft 180 is fitted with a pulley 184 and drive wheel shaft 24
(note also FIG. 2) is fitted with a pulley 185. A resilient O-ring
type belt 186 is entrained about pulleys 184 and 185 to rotate the
drive and stripper wheel shafts as well as controlling the amount
of separation which may occur between the drive and stripper
rollers.
The adjustment of the stripper assembly controls the angular
relationship between stripper wheels 52-53 and drive wheels 23-23c
as well as the angular orientation of the center lines CL of arms
32 and 33 relative to the feed direction. If the angle .alpha. (see
FIG. 7c) is increased beyond a predetermined value, a wedging or
jamming of the sheets occurs. If the angle .alpha. is decreased
beyond a predetermined value (i.e., as shown respectively in FIGS.
7b and 7a), the stripper wheels undergo "bouncing." By selection of
the appropriate positive angle .alpha., (relative to the horizontal
line H) the stripper assembly provides a self-clamping effect to
eliminate "bouncing" and yet prevent the "wedging" or jamming
effect and thereby facilitate handling of sheets over a wide range
of thicknesses, stiffnesses and finishes.
The angle .alpha. is also a function of the coefficient of friction
of the stripper wheel periphery such that .alpha. may be decreased
by increasing the coefficient of friction and vice versa.
The angle .beta. formed between the feed direction and stripper
wheel 52 (see FIGS. 6A and 7c) is also important. If .beta. is too
small, the "wedging" effect will occur. However, .beta. can be
significantly decreased (for example, by increasing the diameter of
wheel 52) due to the counter rotation of the stripper wheels.
Ideally (see FIG. 6A) stripper wheel 52 should be aligned so that a
line drawn through point X on its surface is tangential to line
L.sub.d, line L being coincident with the plane of movement of
sheets in the feed direction. Line L.sub.d should also be
perpendicular to the plane of sheet movement and pass through the
center of rotation of drive wheel 23. The point X need not lie on
the surface of wheel 23.
FIGS. 7a-7c show the various orientations of the stripper assembly
arms 32, 33. In FIG. 7a the shaft 31 about which arms 32, 33 pivot
is positioned below line FL which represents the plane in which
sheets are fed. The direction of rotation of the stripper wheel 52
and the coefficient of friction of the stripper wheel relative to
pivot point 31 tends to lift the stripper wheel 52 off the sheet as
shown by arrow F.sub.1.
The orientation of arms 32, 33 in the "neutral" position (i.e.,
with center line CL parallel to the plane of the sheet [FIG. 7b])
the counter-rotation of wheel 52 exerts a force F.sub.2 along the
center line CL, which force is substantially neutralized, so that
the stripper wheel is free to "bounce."
The orientation of arms 32, 33 with the pivot point 31 positioned
above the plane of the sheet causes counter-rotating stripper wheel
52 to tend to hold the stripper wheel against the sheet and thereby
prevent "bouncing" to provide the aforementioned self-clamping
effect.
The means of imparting rotational movement between pulley 44 and
stripper wheel pulley 51 can therefore be seen to impart the
necessary rotation to stripper wheels 52 and 53 without having any
effect whatsoever upon either the orientation or downward force
exerted by the stripper wheels upon the sheet entering between
stripper wheels 52 and 53 and drive wheels 23-23c.
Drive wheels 23-23c are formed of a resilient material whose
periphery exhibits a high coefficient of friction, while wheels 52
and 53 are formed of a material which, while being somewhat
resilient, are less resilient than wheels 23-23c and whose
peripheries exhibit a coefficient of friction which is less than
that of the peripheries of wheels 23-23c. As can clearly be seen
from FIG. 2, the fact that the lower portions of the peripheries of
wheels 52 and 53 lie slightly below the peripheries of the wheels
23-23c, cause sheet S' to assume an undulating or corrugated
configuration. The peripheries of wheels 52 and 53 are preferably
curved as shown best in FIG. 2, whereby the contour of sheet S'
substantially follows the shape of the curved peripheries. The
severity of the undulations formed in sheet S' is substantially a
function of the spacing between wheels 23 and 23a, and wheels 23b
and 23c, the width of wheels 52 and 53 and the thickness and
inherent strength of the sheet S'. Typically, thinner sheets will
cause the stripper rollers to have their peripheries inserted more
deeply in the gaps provided between the spaced drive rollers
23-23c.
The stripper and drive wheels of FIGS. 2 and 3 may be replaced by
wheels of the type shown in FIGS. 3a or 3b. FIG. 3a shows a drive
wheel 23' having an arcuate shaped groove 23a' for receiving
stripper wheel 52 to impart a corrugated shape to sheet S. The
drive wheel 23" of FIG. 3b has a pair of grooves 23a" and 23b", the
raised portions 52a' and 52b' of stripper wheel 52' to impart a
corrugated configuration to sheet S. If desired, a plurality of
pairs of stripper and drive wheels of the type shown in FIGS. 3a
and 3b may be mounted upon their associated rotating shafts. Also,
the wheel 23" may be provided with a greater number of grooves
(i.e., three or more). If desired, wheel 23' may be mounted upon
the stripper wheel shaft 47 and wheel 52 may be mounted upon the
drive wheel shaft 24. A similar reversal may be made for the wheels
23" and 52' of FIG. 3b.
In cases where only a single sheet (i.e., the bottom-most sheet)
enters into the region between stripper rollers 52 and 53 and drive
rollers 23-23c, the relative coefficients of friction of these
rollers are such that the drive rollers 23-23c exert the primary
influence upon the sheet fed thereto whereby the sheet is caused to
be fed in the forward feed direction and toward acceleration wheels
60, to be more fully described. The coefficient of friction of the
stripper wheel peripheries will cause these wheels to make slipping
engagement with the single sheet fed thereto, which action is
further aided to a degree due to the fact that the stripper wheels
are biased downwardly upon the single sheet by virtue of the weight
of the stripper wheel assembly, and hence the stripper wheels may
be free to move upwardly under the influence of the single sheet as
it is fed therethrough. The undulating configuration of the sheet
acts to greatly stiffen the sheet as it passes between rollers
52-53 and 23-23c to greatly increase the effective frictional
engagement between the sheet and rollers 52-53 and 23-23c.
The most effective frictional engagement is exerted by the "near
edges" of adjacent drive and stripper wheels (i.e., near edges 52a
and 23d, for example) which cooperate to "pinch" the sheet
therebetween and thereby impart their opposing driving forces.
In the case where a pair of sheets are fed toward the drive wheels
23-23c and stripper wheels 52 and 53, which is shown best in FIG.
3, the drive wheels and stripper wheels similarly cause the pair of
sheets to form the undulating pattern shown in FIG. 2 for a single
sheet feed. However, in the regions outside of the gaps G and G',
the effect of the stripper wheels moving at least partially between
the drive wheels causes the sheets S' and S" to be slightly
separated, thereby reducing the amount of surface contact between
the sheets with the primary driving effect of the stripper wheels
and drive wheels occuring in the region where the "near" curved
edges of the wheels are positioned closest to one another as
designated by the locations P as shown in FIG. 3. The separation
between the sheets in the regions outside of the gaps G and G'
greatly facilitate the stripping of the sheet S" from sheet S'. The
coefficient of friction of the stripper wheels 52 and 53 is greater
than the coefficient of friction between the engaging surfaces of
the two contacting sheets S" and S' causing the stripper wheel to
drive the top-most sheet S" backwards toward the infeed hopper
while sheet S' is driven toward the acceleration wheels by the
drive rollers. Similarly, the coefficient of friction of the
peripheries of drive wheels 23-23c is greater than the restraining
frictional forces between the contacting sheets to enable the drive
wheels to move the bottom-most sheet S' toward the acceleration
wheels. Thus, even if the two sheets S' and S" are exactly in
alignment when fed between the drive and stripper wheels, the
stripper wheels are nevertheless effective in "stripping" the
topmost sheet away from the bottom-most sheet and thereby enabling
only the bottom-most sheet to be fed toward the acceleration
wheels.
The stripper wheels 52-53 cause the sheet engaging their
peripheries to be fed rearwardly thereby urging the sheet back
toward the stack. Since the major portion of the weight of the
stacked sheets is removed from the substantially "weight free
pocket" formed within the bottom-most region of the infeed hopper
14, the reverse movement of the sheet fed rearwardly toward the
infeed hopper permits the trailing edge of the sheet to move
rearwardly without experiencing any curling over or bending.
The operation in which two sheets are fed simultaneously occurs as
described hereinabove even though the first sheet which engages the
drive wheels is not the bottom-most sheet (for example, in the case
of a bottom feed arrangement of FIGS. 1 and 2). The sheet will be
advanced by the drive wheels (with the stripper wheels slippingly
engaging the sheet) until the leading edge of the bottom-most sheet
engages the drive wheels. When the bottom-most sheet is advanced so
that portions of both the bottom-most sheet and the sheet above it
are between the stripper and drive wheels, the stripper wheels
exert a greater influence upon the sheet which they engage to drive
the sheet toward the infeed hopper. Once the "bottom-most" sheet is
removed from the influence of drive wheels 23-23c, the drive wheels
exert the major influence upon the sheet still remaining between
wheels 52-53 and 23-23c to cause it to be advanced to the
acceleration wheels behind the "bottom-most" sheet. This operation
assures feeding, separation and stacking of sheets in the same
order as the sheets were arranged in the infeed hopper.
The acceleration wheels are shown best in FIG. 2 and are comprised
of individual wheels 60-60c, all mounted upon a common shaft 61 and
being locked thereto so as to rotate with the rotation of shaft 61.
The shaft is journalled to machine frame F by bearings 63a and 63b
so as to be mounted in a free-wheeling manner relative to the
machine frame. The left-hand end of shaft 61 is provided with a
pulley 62 which cooperates with a belt 63 (shown in phantom line
fashion in FIG. 2 for purposes of simplicity) for imparting the
rotational drive required for the acceleration wheels.
The acceleration wheels cooperate with a plurality of idler rollers
65 (only one of which is shown in FIG. 1 for purposes of
simplicity). The peripheries of the outer idler rollers have a
lower coefficient of friction than the idler rollers associated
with acceleration wheels 60a and 60b. It should be understood that
there is one idler roller arranged in alignment with each of the
acceleration wheels 60-60c which idler rollers are preferably
independently mounted in the manner shown best in FIG. 2b.
The rollers 60a and 60b are tightly aligned near the center of
shaft 61, while rollers 60 and 60c are positioned a large distance
away from rollers 60a and 60b. The peripheries of rollers 60a and
60b have a higher coefficient of friction than rollers 60 and 60c.
Due to the tight alignment of rollers 60a and 60b at the center of
shaft 61 these rollers do not promote skewing of a sheet engaging
the rollers 60a and 60b. In order to prevent the outer rollers 60
and 60c from promoting skewing, the idler rollers cooperating with
acceleration wheels 60 and 60c are positioned slightly downstream
of the idler rollers cooperating with acceleration wheels 60a and
60b. FIG. 2b shows wheel 60 mounted on shaft 61. All of the rollers
60-60c are in alignment. Idler 65a (shown in dotted line fashion)
represents the idler roller which rollingly engages wheel 60a.
Idler 65a is arranged to be tangent to a line which is coincident
with the feed direction (see arrow in FIG. 2b). Idler 65 (shown in
solid line fashion) has its axis of rotation X.sub.1 on the
downstream side of the axis of rotation X of roller 65a. All idler
rollers are mounted by means of a resilient U-shaped member whose
yoke is secured to plate 16 by fastener 302. The arms of a U-shaped
member 301 receive a pin 303 upon which the idler roller is
mounted. U-shaped member 301 urges its idler roller against the
surface of its associated acceleration wheel.
In cases where a sheet is skewed as it advances toward the
acceleration wheels, the alignment of the idler roller's
cooperation with acceleration wheels 60 and 60c is such as to cause
the leading edge LE advanced thereto, to strike the surface of
idler 60 (for example) a spaced distance away from the point
(X.sub.2) where it engages the periphery of wheel 60. This causes
either realignment or a significant reduction in the skewing of the
document. The leading edge will then be directed toward point
X.sub.2 to be accelerated by wheel 60 and idler 65.
In cases where some skewing exists even after the document has
entered between wheels 60a-60b and the associated idlers, the outer
wheels 60 and 60c and their associated idlers assure the fact that
the end portion of the trailing edge which is the last to leave the
influence of the acceleration wheels will nevertheless be advanced
to the stacker.
The infeed hopper plate 16 is provided with a plate portion 16b
integrally joined to plate portion 16a which plate portion 16b is
aligned so as to be arranged in substantially spaced parallel
fashion relative to plate portion 15d of the infeed hopper support
plate 15. Plate portion 16b is provided with suitable openings
sufficient to permit a portion of the peripheries of idler roller
65 to protrude therethrough, in a manner shown best in FIG. 1, so
as to make surface engagement with the periphery of acceleration
wheels 60. The rearward end of portion 16b cooperates with member
15 to define a narrow outfeed "throat" to limit the number of
sheets which may be advanced to drive wheels 23-23c. The centers of
rotation of acceleration wheels 60 are spaced a distance G from the
center of rotation of drive wheels 23, which distance G is
preferably less than the width of the smallest sheet which can be
accommodated by the feed and separating mechanism to cause the
acceleration and idler wheel to grip the sheet before its trailing
edge leaves the drive wheels. However, the spacing may be greater,
if desired, since the drive wheels impart sufficient movement to
sheets passing the drive wheels to assure proper advancement to the
acceleration wheels. The tangential velocity of the peripheries of
acceleration wheels 60 is significantly greater than the tangential
velocity of the peripheries of drive wheels 23-23c to cause the
single sheet fed thereto to move at a greater linear speed as the
leading edge of the single sheet enters between acceleration wheels
60 and their cooperating idler rollers 65. This absolutely assures
the fact that the trailing edge of the sheet passing between
rollers 60 and 65 will clearly be separated by a finite gap from
the leading edge of the next sheet in the stack which is delivered
to rollers 60 and 65 by the drive wheels 23-23c. The gap formed
between succeeding sheets fed between drive wheels 23-23c and
acceleration wheels 60-60c may be used to great advantage by
providing a detector assembly which may be employed for counting
purposes. For example, a light source 71 may be positioned in the
manner shown in FIG. 1 with the light rays emitted therefrom being
directed through suitable openings (not shown for purposes of
simplicity) provided in plate portions 16b and 15d so as to enable
the light rays to pass through these aligned openings and thereby
be detected by the light sensitive photo cell 72. Detection of the
light rays will occur during a time interval between the passage of
the trailing edge of a sheet fed to acceleration wheels 60 and the
leading edge of the next single sheet leaving drive wheels 23-23c.
These pulses may be accumulated by a suitable counter (not
shown).
GATE ASSEMBLY
A gate assembly 200 as shown in FIGS. 1b and 1c is provided for
performing the "statistical sampling" and collating operations and
comprises a gate member 201 rigidly secured to shaft 202. At least
one end of shaft 202, which extends through one sidewall of the
machine frame (not shown for purposes of simplicity) is fitted with
a lever arm 203 rigidly secured thereto. A relay 204 secured to the
machine frame at 205, has its armature 204a secured to arm 203 by
pin 206. With solenoid 204 deenergized, a spring means 207 coupled
between 205 and 206 normally maintains the gate and arm in the
dotted line positions 201' and 203', respectively. Energization of
relay 204 causes the gate and arm to move against the force of
spring 207 to the solid line positions 201 and 203,
respectively.
Let it be assumed that it is desired to count a large number of
sheets while retaining only "statistical samples" of the sheets
being counted (i.e., every 100th sheet). The gate is maintained in
dotted line position 201', causing sheets advanced by the
acceleration sheets to be fed between belts 207 and 208 entrained
about roller pairs 209-210 and 211-212 respectively. Belts 207 and
208 advance the sheets in the direction of arrow 213 where a curved
plate 214 deflects the counter sheets into a waste container 215.
As the trailing edge of the "99th" sheet clears gate 201 and enters
between belts 207 and 208, gate relay 204 is energized to move the
gate to position 201, for deflecting the "100th" sheet toward
stacker 80. As the "100th" sheet passes gate 201, relay 204 is
deenergized to cause the next sheet to be fed toward belts 207-208.
Thus, every "hundredth" sheet is retained as a "sample" while the
remaining sheets may be discarded.
Obviously, any desired statistical sample may be selected by means
of a settable switch 216. As the gap between sheets (i.e., sheets
S.sub.1 and S.sub.2) is detected, the sensor 72 advances the count
of counter 217. The accumulated count in counter 217 is compared
against the setting of settable switch 216 by decoder 218 to
activate a driver circuit 219 which energizes gate relay 204 for
each Nth document to be sampled, where "N" may be any real integer.
The clutch and brake mechanisms described hereinabove may be
activated by an "N-1" signal and an "N+1" signal to assure the
presence of a gap G of sufficient length between the sheet
preceding the "Nth" sheet and the sheet following the "Nth" sheet
to provide sufficient time for the physical movement of gate 201.
The decoding circuitry in decoder 218 generates an N-1 signal when
the trailing edge of the sheet preceding the "Nth" sheet passes
sensor 72, causing the drive, stripper and picker wheels to be
disengaged from the motor drive and be abruptly halted, thereby
"slowing down" the "Nth" document. Gate 201 is moved and the brake
and clutch mechanisms are released to continue the feed operation.
When the trailing edge of the "Nth" sheet is sensed, the above
operation is repeated to allow the gate to be set to position 201'.
The feed operation is again restored until the next statistic
sample is about to pass sensor 72. This gate assembly may also be
used for collating. for example, it may be desired to stack every
"odd" sheet (an original) in one pile, and every "even" sheet (a
carbon copy of its associated original) in a separate stack. This
may be done by operating the gate as described above between every
sheet fed through the apparatus.
ENDORSER
If desired, an endorser or stamping wheel may be positioned
downstream of the acceleration wheels 60. Plate portion 16b is
preferably lengthened to accommodate the endorser roller and a
cooperating elongated idler roller for stamping or "endorsing"
sheets as they pass between the endorser assembly. After leaving
the endorser stage, documents are then stacked in the same manner
as will be more fully described.
Plate 16 has a remaining plate portion 16c integrally joined to
plate portion 16b which forms substantially an acute angle with
plate portion 16b at a bend 16d which causes the path of movement
of single sheets accelerated by wheels 60 (moving in the direction
of arrow 74) to be deflected somewhat so as to move in the
direction shown by arrow 75, whereupon the single sheets are fed to
a stacker assembly 80. The surface 16c acts to realign any sheets
striking surface portion 16c in a skewed manner by causing the end
of the leading edge striking portion 16c to be decelerated somewhat
and thereby move the leading edge uniformly in the forward feed
direction.
The preferred pulley arrangement for operation of the apparatus is
shown best in FIG. 2. The apparatus is provided with a motor M
(also shown in FIG. 1) having output shaft 129 extending through
machine frame F to which motor M is fastened. A pulley 130 is
rigidly secured to shaft 129 and drives the acceleration wheel
shaft 61 by means of a belt 64 entrained about pulleys 130 and 62.
The opposite end of shaft 61 is provided with pulleys 133 and 134.
Pulley 133 is locked to shaft 61 and drives kicker wheel shaft 85
by belt 132, which is entrained about pulley 133 and pulley 89
locked to shaft 85. Belt 132 is a resilient O-ring type belt, and
is looped in "figure 8" fashion to rotate shaft 85 in a direction
reverse that of shaft 61. Thus, whenever motor M is energized,
shafts 61 and 85, which are directly coupled thereto are
rotated.
Shaft 61 is further provided with a clutch 131 which, when
energized, causes the pulley 134 mounted upon clutch 131 to rotate.
When deenergized, clutch 131 causes pulley 134 to be free-wheeling
relative to shaft 61. Belt 135 is entrained about pulley 134 and a
pulley 136, locked to one end of drive wheel shaft 24. The opposite
end of drive wheel shaft 24 has two pulleys 25 and 138 locked to
the shaft. A belt 142 is entrained about pulley 25 and pulley 21,
which is locked to picker wheel shaft 20. Belt 140 is entrained
about pulley 138 and idler shaft pulley 42 which is locked to idler
shaft 39. The shaft 39 serves to impart rotation to the stripper
wheels 52-53 as was previously described.
The pulleys 133 and 89 are provided with semi-circular grooves
around their periphery for receiving O-ring type belt 132. All of
the remaining pulleys are provided with gear-like peripheries for
engaging teeth provided on the belts which they engage, which belts
are commonly referred to as timing belts.
An electromagnetic brake 137 is fastened to the machine frame and
receives one end 20a of picker wheel shaft 20. When energized,
brake 137 abruptly stops shaft 20 from rotating. When deenergized,
brake 137 permits shaft 20 to rotate.
In operation, shafts 61 and 85 rotate as long as motor M is
energized. Clutch 137 permits drive wheel shaft 24, idler shaft 39,
and picker wheel shaft 20 to be selectively disengaged from motor M
when energized. The clutch 131 and brake 137 are operated
substantially simultaneously to both disengage and abruptly halt
the rotation of shafts 24, 39 and 20, even though motor M is
running.
The advantageous features of this design can best be appreciated
from the description of the gate assembly described hereinabove.
This mechanism is also advantageous for use in "batching"
operations, i.e., operations in which a precise number of sheets
are to be arranged in a separate stack. For example, let it be
assumed that paper currency is to be arranged in stacks of 50. The
counter 217 (see FIG. 1b) after counting the 50th bill, energizes
clutch 131 and brake 137 to abruptly stop the operation of the
stripper, drive and picker wheels. The 50th bill is advanced to the
stacker (since the kicker wheels and acceleration wheels are still
running) while the 51st bill is prevented from advancing to the
stacker. The stack of 50 bills may then be removed from the stacker
80 and a "continue" button (not shown for purposes of simplicity)
is depressed to initiate reset counter 217 and deenergize clutch
131 and brake 137 to permit the next stack of 50 bills to be
formed. The size of the batch to be formed is dependent only upon
the setting of settable switch 216 (see FIG. 1b).
STACKER
Each single sheet is fed into the region between plate 16e and
plate 81 of a movable member 112 forming part of the stacker
assembly 80 (see FIGS. 1 and 1a). Each single sheet is kicked
against the base plate 83 of the stacker by means of stacker wheels
84-84c which are mounted upon a common shaft 85 journalled within
bearings 86 and 87 so as to be free-wheeling relative to machine
frame F. Shaft 85 is driven by a pulley member 89 which is coupled
to a suitable pulley belt (not shown for purposes of simplicity) so
as to rotate the stacker wheel in a direction shown by arrow 91
(see FIG. 1) to cause the leading edges of the sheets being fed
thereto by acceleration wheels 60-60c to be "kicked" against base
plate 83. A plurality of elongated strips 83b are arranged on the
top surface of base plate 83 and are arranged in spaced parallel
fashion as shown best in FIG. 1a. The top surfaces are polished to
provide a smooth finish. The strips 83b reduce the amount of
surface area of sliding engagement with the leading edges of the
sheets stacked within the stacker. Wheels 84 preferably have
peripheries exhibiting a coefficient of friction similar to that of
wheels 23-23c, for example. Stacker member 112 is biased by a
spring and pulley mechanism 95 and 96, respectively, which normally
biases the stacker movable member 112 in the direction shown by
arrow 97. As the sheets are deposited within the stacker, movable
member 112 moves in the direction shown by arrow 98 against the
force of spring 95 to form a neat and somewhat compressed stack of
sheets within the stacker. Hooked end 95a of the spring is secured
to a rod R, forming a part of the machine supporting frame, by
fastening member 103. Hooked end 95b of the spring is fitted
through an eyelet 104 secured to bracket 105 which rotatably
supports pulley 106. A second pulley 107 is rotatably mounted upon
bracket 108 which is fixedly secured to the left-hand end of base
plate 83 by an L-shaped bracket 109. A thin tape member 110 has a
first end secured between the yoke of bracket 108 and arm 109, as
shown at 109a, is entrained about pulleys 106 and 107 and has its
opposite end secured between the downward projection 112a of member
112 (which rides in slot 83a) and plate 111 which is secured to
projection 112a by fasteners 111a. Bracket 111 is secured to the
underside of member 112 enabling member 112 to move within an
elongated guide slot 83a provided within base plate 83, while
preventing member 112 from being lifted out of slot 83a. The use of
a block and pulley arrangement yields a mechanical advantage in
that pulley 106 moves only half the distance moved by member 112 to
permit the use of a shorter spring (95) of greater spring
tension.
Plate 16 has a final plate portion 16e integrally joined with plate
portion 16c so as to alter the part of movement of the sheets from
the direction shown by arrow 75 to the direction shown by arrow 76.
Each sheet, in addition to being kicked against stacker base plate
83, is further abruptly urged against the confronting surface of
plate 81, so that its trailing edge (see trailing edge T of sheet
S'" in FIG. 1) is moved a substantial distance away from plate
portion 16e of plate 16 so as to provide clearance for the next
sheet to be fed to the stacker assembly. 6 The high-speed movement
of sheets through apparatus 10 frequently causes the sheets to pick
up some static electric charge, and thereby causing the sheets to
be attracted to surface 16c. The action of kicker wheels 84 serves
to overcome this attraction in driving the sheets against plate 81.
In addition, the kicker wheels urge the leading edges of the sheets
against base plate 83 to stack the sheets in a neat fashion. The
force of spring 95 normally urges member 112 in the direction of
arrow 97 to compress the formed stack. If desired, the plate 81 may
be removed, whereby only upwardly projecting member 112 is employed
in the stacker to support sheets within the stacker. The ends of
the sheets extending laterally of the member 112 experience no
restraining force and thereby form a "butterfly" pattern. However,
the stacking operation is performed as effectively as would be the
case if plate 81 were provided. The removal of plate 81 facilitates
removal of all sheets in the stack, whereas plate 81 obscures the
stack and the possibility that one or more sheets may not have been
removed from the stacker may go undetected.
As can best be seen from FIG. 2, the stripper and drive wheels are
centrally located whereby the influence exerted by these wheels is
applied substantially to the central portions of sheets S'. Since
the edges E and E' of sheet S' may extend a substantial distance
beyond this central region C (note FIG. 2), plate portion 16b of
plate 16 may be provided with a pair of free-hanging "flaps" 99
which are mounted within suitable apertures provided in plate
portion 16b and whose lower edges 99a extend downwardly and into
the infeed opening between plates 16b and 15b. These members extend
downwardly by virtue of their weight and exert a guiding influence
upon the sheets fed toward the drive wheels 23-23c by the picker
wheel 19 to further assure that skewed sheets fed toward the drive
wheels are realigned whereby their leading edges are simultaneously
engaged by the contacting peripheral portions of drive wheels
23-23c and stripper wheels 52 and 53. However, it has been found
that the stripper and drive wheel assemblies have been capable of
feeding only single sheets toward the acceleration wheels, even in
the case where the leading edge of the sheet (or even of the
sheets) is unevenly fed toward the stripper and drive wheels. It
has been found that these assemblies are nevertheless capable of
feeding only single sheets toward the acceleration wheel and that a
gap of finite length sufficient to permit a counting operation will
occur. FIG. 2 shows the relative location of the "flaps" 99 with
respect to the stripper and drive wheels.
FIG. 4 shows another preferred embodiment of the present invention
in which top feeding of the documents may be provided, and wherein
like elements as between the embodiments of FIGS. 1 and 5 are
designated by like numerals.
In this embodiment, the apparatus 10' is mounted upon a suitable
base member 120 forming part of the apparatus frame. A movable tray
member 121' is positioned between a pair of vertical side plates
(not shown for purposes of simplicity) and a biasing means is
mounted between base plate 120 and document advancing support plate
121. The biasing means may, for example, be a plurality of spring
members 122 normally urging member 121' vertically upward. The
stack S of sheets is placed upon support 121' by urging plate 121'
downwardly to a degree sufficient to permit the top of the stack S
to clear support picker wheel 19. The stack may then be released,
causing biasing members 122 to urge the stack of sheets in the
upward vertical direction. Picker wheel 19, which is similar to
that shown in FIGS. 1 and 2, is similarly provided with a raised
portion 19a having a high coefficient of sliding friction to cause
the stack of sheets to be jogged and further to advance the topmost
sheet toward the feed and stripper roll assemblies. A suitable
opening is provided in plate 123 to permit the periphery of picker
wheel 19 to protrude therethrough. The topmost sheet (or sheets)
are advanced by picker wheel 19 in the direction shown by arrow 134
so as to move toward the drive roll assembly comprised of drive
roll 23. The stripper roll 52 is mounted therebeneath, and is
arranged so as to have a portion of its periphery protrude through
its suitable opening provided in lower guide plate 124. The
left-hand end of lower guide plate 124 is provided with a knee
portion 124b joined to a vertically aligned portion 124a, with knee
portion 124b cooperating with upper guide plate 123 to define a
narrow throat region 125 which aids in limiting the number of
sheets advanced to the feed and stripper rolls.
The operation of the feed and stripper rolls is substantially
identical to that described hereinabove, with the stripper wheel
mounting assembly being positioned beneath guide plate 124. The
stripper wheel mounting assembly may be modified so as to provide a
biasing force in the form of a spring means 126 mounted between
each of the arms 32, 33, as shown in FIG. 2 (only one of such arms
being shown in FIG. 5 for purposes of simplicity) and plate 124.
The force exerted by spring 126 urges the stripper rollers in the
direction shown by arrow 126a about pivot shaft 31. The feeding and
stripping operation is substantially identical to that described
hereinabove, wherein a suitable number of feed and stripper rollers
are provided to impart an undulating or corrugated contour to the
sheet or sheets being fed between the feed and stripper rollers. It
should be noted that whereas FIG. 2 shows two stripper rollers 52
and 53, and four feed rollers 23-23c, it should be understood that
any other number of such rollers may be employed and, in fact, the
number of stripper rollers employed may be greater than the number
of driver rollers, if desired. The preferential arrangement is to
provide at least a plurality of both stripper and drive rollers so
as to impart a corrugated or undulated contour to the sheet or
sheets fed therebetween to enhance the stiffening of the sheets fed
therebetween and thereby facilitate their separation over as large
a surface area as is possible. Providing a single stripper roller
having its periphery extending into a gap between a pair of drive
rollers greatly reduces the amount of stiffness imparted to sheets
fed between the driver and stripper rollers and further makes it
possible to cause a single sheet or sheets to be pushed so far
downwardly into the gap between adjacent drive rollers (or stripper
rollers, if such is the case) as to significantly reduce the
effectiveness of the driving and stripping operations.
The drive act to advance only a single sheet toward the
acceleration rollers 60 (only one being shown in FIG. 4 for
purposes of simplicity) which cooperate with their associated idler
rollers 65 to abruptly increase the velocity of single sheets fed
therebetween so as to provide a predetermined gap between the
trailing edge of the sheet passing between the acceleration and
idler rollers and the leading edge of the next sheet to be fed
thereto.
The apparatus of FIG. 4 may be provided with a stacker assembly of
the type shown in FIG. 1 wherein the leading edges of sheets
advanced by acceleration roller 60, and moving in the direction
shown by arrow 134, are caused to be deflected downwardly in the
direction of arrow 135 by plate 136. Kicker wheels 84 cause the
sheets to be altered in their direction of movement from that shown
by arrow 135 to that shown by arrow 137 wherein the sheets are
kicked against base plate 83 and thereby stacked within the
stacker. Surface 136 functions as an anti-skewing surface in the
same manner as that described in connection with the embodiment of
FIG. 1, as does surface 83 which serves to form a neat stack in
cooperation with the operation of kicker wheel 84.
The top feed embodiment of FIG. 4 simplifies the feeding of single
sheets to the drive and stripper assemblies, since the weight of
the stack S is beneath the topmost sheet. The means for moving the
stack S upwardly need only exert a light, upward force upon the
stack so as to place the topmost sheet under the influence of
picker wheel 19. If desired, the upper guide plate 123 may be
provided with a portion 123a pivotally mounted at 123b. A
microswitch 123d is employed to detect the lowering of plate
portion 123a (by counterclockwise rotation about pivot 123b to
drive a motor (not shown) which rotates a threaded shaft S' within
threaded opening 120a in base plate 120). The upper end of shaft S
is secured to platform 121 to drive it upward until the topmost
sheet of the stack abuts against pivoted plate portion 123a to
drive it clockwise, and thereby cause microswitch 123d to
deenergize the motor which operates platform 121. Alternatively,
the infeed hopper arrangement 14 of FIG. 1 may be used with the top
feeder of FIG. 4 by appropriate modification of the platform 121,
plates 123a and 124 and picker wheel 19 to accomplish the weight
relieving advantages of the hopper assembly of FIG. 1 in a top feed
apparatus.
It can be seen from the foregoing description that the present
invention provides a novel feeding and separating mechanism capable
of feeding and stacking single sheets from a large stack of sheets
which may contain sheets of dissimilar sizes, thicknesses and
finishes and, in fact, may even be slightly or partially mutilated
without any effect whatsoever upon the separation operation. The
primary distinctions between the feeding and separating device
described herein over conventional apparatus are:
a. no adjustment is required for any of the machine components to
individually feed sheets of differing sizes, thicknesses, weights
or finishes of paper, plastic or other flat material; also, the
sheets may be fed in stacks containing sheets of either uniform or
differing characteristics or sizes with equal success;
b. the intermixed stock may vary in thickness, over a wide range.
For example, those embodiments already developed are capable of
handling sheets of thicknesses at least within the range from 0.002
to 0.021 inch and are capable, for example, of accommodating sheets
which may vary in width in the range from at least 2.5 to 7 inches
and in the range from at least 2.5 to 24 inches in the direction of
travel;
c. non-uniform and non-square-edged stock may be fed with equal
success;
d. no special car need be given to a stack of sheets, and more
specifically, preliminary jogging or preparation of the stock is
not required;
e. the successful feeding and separation of documents can be seen
to be carried out without the need for any critically adjusted
knife edges or slits, nor supplementary air pressure or vacuum
sources, as are typically required in conventional structures;
f. the proper selection and combination of the materials from which
the driving and stripping rollers are formed virtually eliminates
double stock feeding, thereby eliminating the necessity for the
provision of a doubles detector and other associated circuitry;
and
g. the design of the apparatus is such that there is no mutilation,
bending or curling of the sheets during any phase of the feeding,
separating and stacking operations and the apparatus is virtually
"jam-free" throughout the entire operation.
It should further be noted that the simplicity in design and
operation of the device lends itself readily for feeding of stock
from either a bottom load or top load input device.
Although there has been described a preferred embodiment of this
novel invention, many variations and modifications will now be
apparent to those skilled in the art. Therefore, this invention is
to be limited, not by the specific disclosure herein, but only by
the appending claims.
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