U.S. patent number 3,583,695 [Application Number 04/747,941] was granted by the patent office on 1971-06-08 for workpiece differentiator.
This patent grant is currently assigned to Ivanhoe Research Corporation. Invention is credited to Robert H. Sherwood.
United States Patent |
3,583,695 |
Sherwood |
June 8, 1971 |
WORKPIECE DIFFERENTIATOR
Abstract
A rotating cylinder-type differentiator in which the high
friction material of the differentiator is deformable and enlarges
the area of contact in response to low pressure contact between the
high friction material and the workpiece to be differentiated. The
illustrated form of deformable material is a flying flap. The
flying flap, which is attached at one at one end to the cylinder,
flies out from the surface of the cylinder as the cylinder is
rotated. The flyout feature functions to virtually increase the
radius of the cylinder and actually increases the area of initial
contact between the high friction material and the workpiece being
separated. Alternate arrangements include a biased flap, a modified
rotating cylinder and other forms of deformable, resilient material
such as deformable, resilient sponge rubber and fluid containing
materials.
Inventors: |
Sherwood; Robert H. (Old
Saybrook, CT) |
Assignee: |
Ivanhoe Research Corporation
(New York, NY)
|
Family
ID: |
25007337 |
Appl.
No.: |
04/747,941 |
Filed: |
July 26, 1968 |
Current U.S.
Class: |
271/21 |
Current CPC
Class: |
B65H
3/02 (20130101) |
Current International
Class: |
B65H
3/02 (20060101); B65h 003/30 () |
Field of
Search: |
;271/26,21,19,20 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Blunk; Evon C.
Assistant Examiner: Watts; Douglas D.
Claims
What I claim is:
1. Apparatus for separating the top workpiece from a stack of
workpieces including;
support means for supporting a stack of workpieces,
first clamp means engageable upon the top the stack for isolating a
first portion of the top workpiece against lateral
displacement,
a rotatable friction member having a high friction surface
engageable with the upper surface of the top workpiece near said
first clamp means, said rotatable friction member engageable on a
second portion of said workpiece, said rotatable friction member
including
a cylinder mounted for rotating on an axle
a sheet of high friction material having substantially resilient
characteristics and at least one surface of which is a high
friction surface with respect to the surface of the workpieces in
said stack and
means for coupling one end of said sheet to said cylinder, thereby
leaving the other end a free end,
drive means for rotating said rotatable friction member for
displacing said second portion of said workpiece to a position so
that said second portion is relocated wholly between said first
clamp and said friction member for exposing a portion of the
adjacent workpiece in said stack, said exposed portion of said
adjacent workpiece corresponding to said portion of said top
workpiece wholly located,
second clamp means for engaging the exposed said corresponding
portion of said adjacent workpiece on said stock for arresting the
remainder of said stack and
means for disengaging said first clamp means from said top
workpiece for permitting removal of said top workpiece from said
arrested stack.
2. Apparatus for separating the top workpiece from a stack of
workpieces as in claim 1 and in which said rotatable friction
member further includes means for biasing the free end of said
sheet away from the surface of said cylinder.
3. Apparatus for separating the top workpiece from a stack of
workpieces as in claim 1 and in which said cylinder is
substantially hollow and serves for storing a portion of said sheet
of high friction material.
4. Apparatus for separating the top workpiece from a stack
workpieces including:
support means for supporting a stack of workpieces,
first clamp means engageable upon the top of the stack for
arresting all the workpieces in the stack and for separating the
top workpiece on the stack into a first portion and a second
portion,
a rotatable friction member engageable with the upper surface of
the top workpiece and wholly within said first portion of said top
workpiece, said rotatable friction member including
an axle and means for rotating said axle about its longitudinal
axis,
a circumferentially shaped flap having at least one high friction
surface,
means coupled to said axle forming at least a circumferential
segment having the same radius throughout, and
means for coupling said circumferentially shaped flap to said means
forming at least a circumferential segment so that one end of said
flap is free and flies out from said segment in response to inertia
when said friction member is rotated,
drive means for rotating said friction member for bringing said
flap in contact with the upper surface of said workpiece within
said portion for displacing said first portion and for exposing a
portion of the adjacent workpiece in the stack corresponding to the
portion of the top workpiece so displaced,
second clamp means for engaging the stack upon the said exposed
portion of the adjacent workpiece for arresting the stack, except
for said top workpiece and
means for disengaging said first clamp means for releasing all the
workpiece so arrested by engagement by said first clamp means for
permitting removal of said top workpiece from the stack so arrested
by said second clamp means.
5. Apparatus for separating the top workpiece from a stack of
workpieces as in claim 4 and in which said circumferentially shaped
flap is
a sheet of material having at least one surface having high
friction characteristics.
6. Apparatus for separating the top workpiece from a stack of
workpieces as in claim 4 and in which said circumferentially shaped
flap is
a sheet of material having at least one surface having high
friction characteristics and
said material of said sheet is sufficiently resilient to exhibit
springlike behavior.
7. Apparatus for separating the top workpiece from a stack of
workpieces as in claim 5 and further including
means for biasing the free end of said flap of sheet material away
from said means forming at least a circumferential segment.
8. Apparatus for separating the top workpiece from a stack of
workpieces as in claim 5 and in which said means forming at least a
circumferential segment is a cylinder and said cylinder
includes
a hollow portion for internally storing part of the sheet of
material for providing a reserve of high friction surface
material.
9. Apparatus for separating the top workpiece from a stack of
workpieces and for removing the separated workpiece from the stack
including;
means for supporting a stack of workpieces,
first clamp means engageable upon the top of the stack for
arresting all the workpieces in the stack and for separating the
top workpiece on the stack into a first portion and a second
portion,
a rotatable friction member engageable with the upper surface of
the top workpiece and within said first portion of said top
workpiece, said rotatable friction member including
a cylinder and means for rotating said cylinder about its
longitudinal axis,
a sheet of high friction material one end of which is connected to
said cylinder with the other end thereof free for forming a flying
flap and
means for coupling said sheet to said cylinder,
drive means for rotating said friction member for bringing the
flying flap into contact with the upper surface of the top
workpiece for displacing the first portion of the top workpiece and
for exposing a corresponding portion of the adjacent workpiece in
the stack,
second clamp means for engaging the stack upon the said exposed
portion of the adjacent workpiece for arresting the stack of
workpieces except for said top workpiece, and
means for disengaging said first clamp means for releasing said top
workpiece from arrest for permitting removal of said top workpiece
form the stack.
10. Apparatus for separating the top workpieces as in claim 9 and
further including
means engageable with the second portion of said top workpiece for
coupling to said top workpiece and
means for driving said engageable means for removing said top
workpiece from the stack of workpieces.
11. Fabric workpiece differentiator apparatus for differentiating
the top fabric workpiece for separating the top workpiece from a
stack of workpieces comprising;
support means for supporting the stack of workpieces,
first clamp means,
mounting means carrying said first clamp means in a position
located over said stack of workpieces and spaced inwardly from the
edge of the top workpiece,
means for moving said first clamp means downwardly into engagement
with the top workpiece at a position spaced inwardly from the edge
thereof,
a rotatable friction member engageable upon the top workpiece at a
position close to said first clamp means, said position being
between said first clamp means and said edge of the top
workpiece,
said rotatable friction member including deformable resilient means
increasing the virtual radius of said rotatable member for engaging
the top surface of the top workpiece with a high friction grip over
an extended area of contact extending longitudinally over the top
surface of the workpiece with low pressure contact over said
extended area, said resilient means extending outwardly from said
rotatable member and engaging the top surface of the top workpiece
over an extended area of contact remote from the rotatable
member,
drive means for rotating said rotatable member for moving said
resilient means toward said first clamp means while said resilient
means is engaging the top workpiece for displacing the edge portion
of the top workpiece upwardly away from the stack to a relocated
position upwardly generally between said rotatable member and said
first clamp means,
second clamp means,
means for engaging said second clamp means on the stack nearer the
edge thereof than said rotatable member, and
means for disengaging said first clamp means from said top
workpiece for permitting removal thereof from the stack while said
second clamp means serves to hold the stack in position on the
support means.
12. Fabric workpiece differentiator apparatus for differentiating
the top fabric workpiece from a stack of workpieces as claimed in
claim 11, in which said resilient means engages the top surface of
the top workpiece over an extended area extending from an initial
point of contact over the top surface of the workpiece a portion of
the distance toward said edge of the workpiece.
13. Apparatus for separating the top workpiece from a stack of
workpieces including:
means for supporting a stack of workpieces,
first clamp means engageable on the top of the stack for isolating
a first portion of the top workpiece against lateral
displacement,
a rotatable friction member having a high friction surface
engageable with the upper surface of the top workpiece near said
first clamp means, said rotatable friction member engageable on a
second portion of said workpiece, said friction member
including,
deformable, resilient means normally extending to a virtual radius
and deformable under low pressure for enlarging the area of
engagement with said upper surface,
drive means for rotating said rotatable friction member for
displacing said second portion to a position wholly relocated
between said first clamp and said friction member for exposing a
portion of the adjacent workpiece in the stack, said exposed
portion of said adjacent workpiece corresponding to said portion of
said top workpiece wholly relocated,
second clamp means for engaging said exposed portion on said stack
for arresting the remainder of said stack and
means for disengaging said first clamp means from said top
workpiece for permitting removal of said top workpiece from said
arrested stack.
14. Apparatus for separating the top workpiece from a stack of
workpieces as in claim 13 and in which said rotatable friction
member further includes
a cylinder mounted for rotating on an axle and
said deformable, resilient means normally extends beyond the radius
of said cylinder for forming an extended virtual radius.
15. Apparatus for separating the top workpiece from a stack of
workpieces as in claim 13 and in which said rotatable friction
member includes
an axle on which said rotatable friction member rotates,
means coupled to said axle defining a radius therefrom and said
deformable resilient means is coupled to said means coupled to said
axle.
16. Apparatus for separating the top workpiece from a stack of
workpieces from a stack of workpieces as in claim 13 and in which
said rotatable friction member includes
an axle on which said rotatable friction member rotates,
means coupled to said axle for supporting said deformable,
resilient means and
said deformable, resilient means is sponge rubber.
17. Apparatus for separating the top workpiece from a stack of
workpieces including;
means for supporting a stack of workpieces
clamp means engageable on the top of the stack for separating the
top workpiece into a first section and a second section,
a rotatable friction member engageable with the upper surface of
the top workpiece near said clamp means on said second portion,
said rotatable friction member including,
means for defining an axis on which said rotatable friction member
rotates,
means, coupled to said means for defining an axis for defining a
radius extending from said axis,
deformable resilient means having a high friction surface and
coupled to said radius defining means adapted for increasing the
radius of said radius defining means in absence of engagement of
said deformable resilient means with said upper surface of said top
workpiece and said deformable, resilient means adapted for reducing
the increase of said increased radius upon engagement with said
upper surface of said workpiece for enlarging the area of
engagement with said upper surface,
drive means for rotating said rotatable friction member for
displacing said second section to the relocated position wholly
between said clamp means and said friction member and
means for disengaging said clamp means for permitting removal of
said top workpiece from said stack.
18. Apparatus for separating the top workpiece from a stack as in
claim 17 and further including
second clamp means engageable upon the remainder of the stack after
said second section of said top workpiece is relocated for
arresting the remainder of said stack.
Description
The present invention relates to improved apparatus for separating
the top workpiece of limp material from a stack of workpieces of
limp material so that workpieces may be singularly separated from a
stack and may be singularly removed from the stack. The art of so
separating workpieces, one at a time from a stack of workpieces is
normally referred to as "differentiating" and the apparatus for
accomplishing the one-at-a-time separation is normally referred to
as the "differentiator."
The differentiating of limp materials such as fabric material,
whether natural, synthetic, or a combination of natural and
synthetic, whether felted or nonfelted or any other form of limp
material has very unique problems. Adjacent limp material
workpieces in a stack of workpieces have a great tendency to bond
together. This bond must be overcome, such as by being broken or
sheared in order to accomplish unitary separation in singular
units. Limp materials are very often porous to the extent that
vacuum pickup apparatus sometimes picks two or more workpieces from
the same stack instead of one piece. Many types of limp fabric
material are delicate and may be easily marked, damaged, defaced
and/or distorted by relatively rough handling by the differentiator
apparatus.
In differentiating delicate, limp fabric, porous material
workpieces singularly from a stack of delicate, limp fabric, porous
material workpieces, the step of breaking the bond between adjacent
workpieces without causing damage or injury to the material is very
difficult. Differentiating the top workpieces singularly, by
contact with a small area of the workpiece must exert sufficient
friction between the differentiator and the top of the workpiece to
overcome the bond between the top workpiece and second or adjacent
workpiece in the stack. Such amount of friction on a small area of
the delicate material very often damages and/or distorts the fiber,
weave or material content of the material by damaging and/or
displacing the fiber threads of the material, or marking and/or
otherwise damaging or defacing the material of the workpiece being
differentiated.
In prior rotating cylinder-type differentiators the high friction
surface of the differentiator contacting the workpiece may be
enlarged laterally (widthwise) to the width of the workpiece but to
increase the contact area longitudinal (lengthwise) without
increasing the pressure of the cylinder on the cylinder on the top
workpiece was not accomplished, except for enlarging the diameter
of the cylinder which is undesirable since this increases the mass
of the differentiator apparatus.
My improved rotating cylinder-type differentiator employs a novel
structure, heretofore undiscovered, which increases the high
friction area of contact longitudinally between the differentiator
and the top workpiece without increasing the pressure of the
rotating cylinder.
In its preferred form my novel approach employs, what I have
referred to as, a flying flap, high friction material which, aided
by the natural force of inertia, reaches out and extends or
increases the high friction contact area on the top surface of the
top workpiece so that the high friction force on any incremental
area of the contact area used to break or shear the bond between
the top workpiece and the second or adjacent workpiece in a stack
is reduced to the point where damage or injury to the fiber of the
fabric by the differentiating friction force is eliminated.
The flying flap increases the virtual diameter of the cylinder
without actually increasing the actual diameter of the cylinder as
the cylinder is rotated. Inertial force causes the flap to fly out
away from the cylinder surface when the cylinder is rotated and
there is no obstruction which interferes with such flying out.
Thus, a relatively small accurate portion of the cylinder
circumference which normally contacts the flat upper surface of the
top workpiece is enlarged by a virtual increase in the diameter (or
radius) of the cylinder, created by a flying flap of high friction
material. In addition, the flying-out of the flying flap tends to
deform and thus flatten the contour of the high friction surface
thereby further enlarging the high friction surface contact
area.
Preferably, the material used for the flying flap has sufficient
resiliency to exhibit "springlike" behavior. The high friction
characteristic may be a function of an adhesive quality of the
surface.
The flying flap friction material is preferably emery cloth or
emery paper or sand paper, coupled at one edge to the rotating
cylinder with the opposite, edge free. If desired, other high
friction material such as rubberized cloth, adhesive cloth or paper
or other high friction material capable of flying-out upon rotation
may be used in lieu of emery cloth or emery paper. When it is found
that the rotation of the cylinder is too slow and/or the material
content of the flying flap is too stiff to cause the flying flap to
"flyout," the free edge of the flap may be biased or spring loaded
by a light, resilient spring or spring material to effectively
"pushout" the free end of the flying flap and thus effectively
extend the virtual radius of the cylinder.
Another form of my differentiator includes a deformable, resilient
material such as sponge rubber or other readily deformable means of
a fluid-filled deformable high friction material, deformable in
response to low pressure contact for providing an extended contact
area, extending longitudinally over the surface of the workpiece to
be differentiated with low contact pressure distributed over the
contact area or surface.
It is an object of the present invention to provide an improved
differentiator of the rotating cylinder type in which the high
friction contact area is remote from the cylinder.
Another object is to provide an improved rotating cylinder-type
differentiator in which the high friction contact area is a
deformable, resilient material which effectively virtually
increases the radius of the cylinder.
Another object is to provide an to provide an improved rotating
type differentiator in which the high friction contact area is
deformable under low pressure contact and enlarges the contact area
between the high friction surface and the surface of the workpiece
and distributes low contact pressure over the contact area.
These and other objects will become apparent from reading the
following detailed description with reference to the accompanying
drawings in which:
FIG. 1 is side elevation view of the preferred form of
differentiator apparatus with the flying flap making the initial
contact with the top workpiece on a stack of workpieces;
FIG. 2 is a side elevation view of the differentiator apparatus
with the rotating cylinder in the process of relocating a portion
of the top workpiece;
FIG. 3 is a side elevation view of the differentiator apparatus in
which an isolated portion of the top workpiece has been fully
relocated;
FIG. 4 is a side elevation view of the differentiator apparatus
showing the top workpiece being removed from the stack;
FIG. 5 is perspective view of the cylinder of the differentiator
showing the flying flap of high friction and a supply of high
friction in storage;
FIG. 6 is a sectional view of part of the cylinder of the
differentiator showing the flying flap making essentially initial
contact with the top of a workpiece, and
FIG. 7 is a perspective view of part of an alternate arrangement of
a modified "cylinder-type" flying flap differentiator.
Referring in more detail to the drawings FIGS. 1 through 4
inclusive illustrate various stages of the process of
differentiating or separating the top workpiece from a stack of
workpieces employing the present improved differentiator apparatus.
A stack of workpieces 10 is positioned in a surface 11. The
workpiece 12 is illustrated as the top workpiece in a stack of
workpieces 10 although the workpiece 12 could be the only workpiece
positioned on surface 11.
The differentiator apparatus includes a mounting 16 which supports
the arm 17 and the rocker arm 18 of the stack retaining or edge
clamp 19. The rocker arm 18 is pivotally connected to the mounting
16 by the rod or pin 20. A cam lobe 21 is mounted on the mounting
16 and rotates, in phase with other rotating or driven members, by
a drive means (not shown) for synchronously raising and lowering
the stack retaining clamp 19 against a bias spring 22. The cam lobe
21 works against a cam follower 23 for raising (See FIG. 1) the
stack retaining clamp 19 while the bias spring 22, positioned on
the opposite side of the pivot pin 20, urges the clamp 19 downward
for holding the stack 10.
The arm 17 is pivotally mounted on the mounting 16 so that the
workpiece separating clamp 26 and the head or cylinder mounting 27
coupled to the arm 17 may be raised or lowered, with respect to the
workpiece to be, or being, differentiated. In FIGS. 1, 2 and 3 the
separating clamp 26 and head 27 are illustrated lowered onto the
top workpiece 12. In FIG. 4 the separating clamp 26 and head 27 are
illustrated raised above the top workpiece.
The head 27 supports a cylinder 30 which is mounted for rotating
about the axle 31. The cylinder 30 is rotated in synchronism with
the vertical movements or position of the separating clamp 26 and
head 27 and each operated in synchronism with the rotating cam lobe
21.
Another cam lobe may be used to pivotally raise and lower the arm
17 so as to position the separating clamp 26 and 27 (and the
cylinder 30) with respect to the top workpiece and a belt or chain
drive (not shown) may be used to rotate the cylinder by means of a
pulley wheel or gear (not shown) coupled to the axle, the cylinder
30 being rotated in synchronism with its own vertical motion.
Coupled to the cylinder 30, as clearly seen in FIGS. 5 and 6 is a
sheet of high friction material forming a flap 35 such as emery
cloth, for example. The high friction material is coupled to the
cylinder 30 so that one end is free, forming such flap of material,
in this case referred to as a flying flap. The exterior of the
cylinder is essentially a smooth, low friction surface, relative to
the workpiece. The high friction material is high friction relative
to the same workpiece.
As the cylinder 30 rotates on its axle 31, the flying flap 35 tends
to effectively increase the radius of the cylinder, aided by the
force of inertia, by flying out.
The one end of the flying flap 35 is coupled to the cylinder 30 by
a snap catch 36. Other means of securing the high friction material
to the cylinder may be used if desired. The cylinder 30 is
illustrated as a hollow cylinder and a length of the high friction
material of the flying flap may be stored in the cylinder. A pair
of end plates such as 38 may be coupled to the ends of the cylinder
and also serve as bearing mounts for the axle 31.
The flying flap 35 is adjustable lengthwise. The snap catch 36 may
be released and high friction material may be drawn from the inside
of the cylinder to lengthen the flying flap to the extent of the
amount stored in the cylinder.
It is preferred that the length of the flying flap be substantially
equal to the length of the workpiece measured form the point of
initial contact 40 by the flying flap with the workpiece 12 (as
seen in FIG. 1) to the end 41 of the portion of the workpiece 12 to
be displaced. In some cases the flying flap 35 may be shorter in
length than the distance between point of initial contact 40 and
the end 41. It should not be longer than the distance to the
workpiece end 41, because the flap might then engage the next
adjacent workpiece after the top workpiece has been partially
relocated into the position as shown in FIG. 2.
The separating clamp 26 is adjustable both vertically and
horizontally. The thumb screw 45 represents an adjustment means for
moving the clamp 36 horizontally for adjusting the position of the
foot 46 of clamp 26 relative to the contact point 40.
The thumb screw 47 represents an adjustment means for moving the
clamp 26 (and the foot 46) vertically, with respect to the shoulder
49 on the head 27. By adjusting the vertical position of the clamp
26 (and the foot 46) the position of the cylinder 30, relative to
the top workpiece, may also be adjusted.
A bar 17a (shown in FIG. 2 and omitted from FIGS. 1, 3 and 4 for
the sake of clarity) forms part of a parallelogram linkage for
supporting the head 27. This type of coupling prevents unwanted
tipping or tilting of the head assembly, including the head 27, the
separating clamp 26 and clamp foot 46. It will be appreciated that
as each successive top workpiece is removed or differentiated from
the stack, the head assembly will go lower, with respect to the
surface 11, when lowered on stack 10. A parallelogram linkage for
supporting the head assembly assures that the vertical position,
i.e. essentially normal to the surface of the top workpiece on the
stack, is maintained.
In the technique of using the present differentiator apparatus, the
desirable position of the bottom of the cylinder 30 relative to the
top workpiece 12 at the time when the clamp 46 is resting upon the
workpiece 12, and the distance between the edge 48 of the foot 46
and the cylinder 30 depends upon the stiffness of the workpiece
being differentiated. For very stiff and/or heavy bodied material
such as denim, twill, canvas and other closely and/or coarse woven
materials, for example, the differentiator apparatus has been found
to operate satisfactorily with the cylinder closely adjacent and
contacting the top workpiece 12 at the time when the clamp 46
resets upon the top workpiece and the distance between the toe 48
and the point of initial contact of the high friction material
(point 40 in FIG. 1) relatively large. For very flimsy and delicate
material, such as material used to make lingerie, for example,
satisfactory operation has been obtained with the cylinder somewhat
separated or spaced from the top workpiece at the time when the
clamp somewhat separated or spaced from the top workpiece at the
time when the clamp 46 resets upon the top workpiece 12 so that the
flying flap 35 makes light pressure contact with the top workpiece,
such as illustrated in FIG. 6, and the clamp 26 positioned so that
the toe 48 is relatively close to the point of initial contact,
40.
The distance or spacing between the toe 48 and the point of initial
contact 40 ultimately depends upon many factors. Among these
factors consideration should be given to the diameter of the
cylinder 30; the thickness of the foot 46 at the toe 48; the
characteristics of the flying flap, i.e. its roughness, and
stiffness; the fabric of the workpiece i.e. characteristics of the
threads; the tightness of the weave, and the delicate nature of the
material of the workpiece.
The distance or spacing may best be measured as the distance from
the toe 48 to a vertical passing through the axis of the cylinder
30. The vertical is seen as broken line 65 in FIG. 4. By adjusting
the spacing between the toe 48 and the contact point 40 the spacing
between the toe 48 and the surface of the cylinder 30 is being
adjusted.
It will be appreciated that in order to relocate the section b
sufficient spacing must be provided between the toe 48 and the
surface of the cylinder 30 (see FIG. 2). The space required depends
partly on how tightly the material of the workpiece will bend or
flex.
In successful practice it has been found that the distance or
spacing between the toe 48 and the surface of the cylinder 30 at
least exceeds twice the thickness or the workpiece plus the
thickness of the flying flap 35.
Briefly viewing the various phases of the operating cycle of the
differentiator apparatus, FIG. 1 shows the initial step or phase
where the differentiating assembly has been lowered onto the stack
10 with the separator clamp 26, and particularly the foot 46
separating the top workpiece 12 into two sections, a and b. The
section b is to be relocated. The stack retaining or edge clamp 19
is held off the stack by the cam lobe 21 contacting the cam
follower 23. The cylinder 30 is rotating on the axle 31 and the
flying flap 35 is making initial contact with the upper surface of
the top workpiece 21 within the section b. The take-away mechanism,
represented by a vacuum pickup with a head 50 and a vacuum chamber
51 is employed to removed the top workpiece after the workpiece is
initially isolated or separated from the other workpieces on stack
10.
Attention is direction to FIG. 6 which shows the flying flap 35
making the initial contact with the upper surface of the top
workpiece 12. It will be noted that a relatively large area of
contact C is created by the flying flap 35. This large area of
contact C extends from the initial point of contact 40 over toward
the end 41 of the workpiece thus providing a large region of high
friction engagement. With such a relatively large contact area only
minimal pressure between the flying flap 35 and the workpiece 12 is
needed to overcome the bond between the top workpiece 12 and the
workpiece adjacent to the top workpiece on the stack. The use of
only a minimal pressure is very important when the material content
of the workpiece is dainty and/or flimsy.
In addition, FIG. 6 illustrates an alternate arrangement with the
flying flap 35 spring loaded by a very light spring such as
represented by 55. The spring 55 is compressible under very light
pressure to recess into the chamber 56. If rotation of the cylinder
30 is slow and/or not enough inertia force is generated to cause
the flying flap 35 to "flyout" as desired, a resilient means such a
spring or other resilient material or component may be used to urge
and hold the flying end of the flying flapout, away from the
surface of the cylinder, when there is substantially no pressure to
force the flap against the surface of the cylinder 30.
It will be noted that the length of the flap is such that the end
of the flying flap substantially coincides with the end 41 of the
workpiece 12.
In FIG. 2 it will be noted that the cylinder 30 has rotated some
90.degree. and the portion b of the workpiece 12 has been almost
totally removed from the stack. The adjacent workpiece 12a has been
exposed in the portion or segment b and the cam lobe 21, rotating
in synchronism with the cylinder 30 released the cam follower 23
and the spring 22 urges the edge clamp 19 down onto the exposed
portion of the stack.
The take-away head 50/51 has been lowered onto the stack in that
portion a.
FIG. 3 shows the cylinder 30 having advanced in rotation another
90.degree. and the segment b of workpiece 12 has been totally
relocated. The relocation of the segment b is effected by the high
friction material of the flying flap breaking or shearing the bond
between adjacent workpieces (the top workpiece and the next
workpiece in the stack) in this stack 10 so the flying flap
advances or rotates and pulls the segment b of the workpiece 12
along with the flying flap. The flying flap continues to rotate,
pulling away from the relocated segment during such rotational
advance.
The action of the separating clamp 26 and the clamp foot 46 is
passive. The clamp separates the top workpiece into two parts, a
and b. The part b is the part that is relocated or repositioned
while the part a remains substantially undisturbed during
relocation of part b.
With the part b separated or removed (physically) from the stack
(FIG. 3) the remainder of the stack may be secured to the surface
11 by the edge clamp 19.
FIG. 4 shows that the separating clamp 26 has been raised off the
stack and the cylinder 30 has been rotated another 90.degree.. The
separating clamp 26 is lifted (along with the head 27 and cylinder
30 by pivotally elevating the arm 17 about a pivot not shown) which
may be similar to pivot 20 through cooperation of a rotating cam
lobe and follower (not shown) which may be similar to cam lobe 21
and cam follower 23.
With the separating clamp 26 and foot 46 elevated above the stack
the workpiece 12 may be removed by the take-away mechanism.
If the take-away mechanism is a vacuum head, as illustrated and the
vacuum cup 59 holds two or more workpieces such as 12 and 12a, only
the top workpiece 12 may be removed because the workpiece 12 has
been differentiated from the stack by relocated of its portion b
and the rest of the workpieces in the stack are secured to the
surface 11, as a unit by the edge clamp 19.
The take-away head 50/51 preferably follows a path such as
represented by the arrow 57 to effect a shearing-separating action
for removing the top workpiece from the stack.
Referring the FIG. 7, a modified arrangement a flying flap
differentiator mounted cylinder is shown. The axle 31 is FIG. 7
corresponds to the axle 31 in the FIGS. 1 through 5 and may be
mounted and serve for a drive receiving means. The surface or
circumference of the cylinder 30 (as seen in FIG. 5, for example)
has been reduced in FIG. 7 so that it is a segment of the surface.
This is illustrated as 61. The segment is coupled to a leaf 60
which extends from the axle 31. The segment 61 is coupled to the
leaf 60 which extends from the axle 31. The segment 61 is coupled
to the leaf 60 by a screw 62.
The high friction material forming the flying flap 35 is coupled to
the modified "cylinder" by the screw 62. The segment 61 backs-up
the flying flap 35.
It will be seen in the preferred from and in the alternate or
modified forms of the flying flap differentiator that the flying
flap is backed-up by the surface of the cylinder. This essentially
limits the reduction of the radius assumed by the flying flap high
friction material during removal or repositioning of the removable
section of the top workpiece. The increase of the virtual radius,
which effectively increases the contact area of the flying flap, is
a function of the speed of rotation of the cylinder, the resiliency
or springlike behavior of the flying flap material and/or the
strength or effectiveness of the spring or resilient material of
the component removing the flying flap from the surface or backup
portion of the cylinder.
In an alternate form, the high friction material may be deformable,
resilient sponge rubber which, under its own resiliency extends
beyond the actual radius of the cylinder when it is free from
pressure, and when in contact with the surface of the workpiece,
deforms and enlarges the area of contact. Such readily deformable
material enlarges the actual contact area and enlarges the actual
contact area and distributes a low pressure contact over the
enlarged contacted area.
In another alternate form, the high friction material may be a
fluid-filled incapsulation, the contour of which is readily
deformable under pressure.
In describing the apparatus of my improved differentiator I have
described some techniques of usage and have mentioned some
alternate arrangements. Other changes, substitutions and
rearrangements maybe made, as will be familiar to those skilled in
the art, without departing from the spirit of the invention as
defined in the appended claims.
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