U.S. patent number 3,632,030 [Application Number 05/002,729] was granted by the patent office on 1972-01-04 for pneumatic fabric-guiding system.
This patent grant is currently assigned to Samcoe Holding Corporation. Invention is credited to Frank Catallo, Eugene Cohn.
United States Patent |
3,632,030 |
Cohn , et al. |
January 4, 1972 |
PNEUMATIC FABRIC-GUIDING SYSTEM
Abstract
An air-operated fabric-guiding system is disclosed. The new
system is disposed along and encompasses the edge portions of a
laterally disposed fabric. Sensors and actuators are provided for
causing an outward discharge of air along the surface of the fabric
in response to movement of the fabric from a predetermined course.
The air emission on one side of the fabric causes a shifting of the
fabric in the direction of the air emission, thereby realigning the
fabric on the predetermined course.
Inventors: |
Cohn; Eugene (Great Neck,
NY), Catallo; Frank (Elmont, NY) |
Assignee: |
Samcoe Holding Corporation
(Woodside, NY)
|
Family
ID: |
26670788 |
Appl.
No.: |
05/002,729 |
Filed: |
January 14, 1970 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
611609 |
Jan 25, 1967 |
3494011 |
|
|
|
Current U.S.
Class: |
26/75; 26/98;
226/3; 226/7; 226/15; 226/196.1; 242/615.11 |
Current CPC
Class: |
D06C
3/06 (20130101); D06C 3/065 (20130101); D06C
3/026 (20130101) |
Current International
Class: |
D06C
3/00 (20060101); D06C 3/02 (20060101); D06C
3/06 (20060101); B65h 023/24 () |
Field of
Search: |
;226/7,3,15,97
;26/54-56 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Schacher; Richard A.
Parent Case Text
This application is a division of our copending application Ser.
No. 611,609, for "Method and Apparatus for the Handling and
Treatment of Knitted Fabrics, Particularly in the Open Width,"
filed Jan. 25, 1967, and now U.S. Pat. No. 3,499,011 which
discloses a processing line for knitted fabrics including the
guiding device of this application and specific downstream
processing units.
Claims
We claim:
1. Means for handling and guiding web materials such as open width
knitted fabric, comprising
a. air nozzle means disposed adjacent at least opposite side edges
of the web material and embracing at least the side edge margins
thereof in straddling relation,
b. said air nozzle means being arranged to direct controlled flows
of air transversely outward over the opposed surfaces of the web
material toward the edge extremities thereof,
c. means to sense the edge extremities of the web material, and
d. means to control the effectiveness of the respective air nozzle
means to maintain the web material substantially centered relative
to said nozzle means.
2. The handling and guiding means of claim 1, further characterized
by
a. separate air blowers being provided for the separate air nozzle
means, and
b. said means for controlling the effectiveness of said air nozzle
means including power control means for said blowers, whereby the
effective blower power applied to a given side margin of the web
material is reduced, relative to power applied at the opposite
side, in response to wandering of the web toward said given
side.
3. The handling and guiding means of claim 1, further characterized
by
a. the effective dimensions of said air nozzle means, transverse of
the web material, being substantially less than the maximum width
capacity of the equipment, and
b. means being provided for adjusting the separate air nozzle means
toward and away from a center axis to accommodate web materials of
various width dimensions.
4. The handling and guiding means of claim 1, further characterized
by
a. the separate air nozzle means being in the structural form of an
elongated U in external configuration, with the legs of the U
closely embracing the side margins of the web material facing
opposing surfaces thereof,
b. each of the legs of the U being divided internally to form a
first flow passage for flowing air inward toward the center axis of
the web material and a second flow passage for redirecting the
airflow outwardly toward the edges of the web,
c. said second flow passage terminating in a flow discharge opening
spaced inward from the edge of the web.
5. The handling and guiding means of claim 1, further characterized
by
a. said sensing means comprising a freely pivoted mercury switch or
the like,
b. a sensing arm connected to the mercury switch and maintained by
gravity in a sensing position,
c. said switch and sensing arm being counterbalanced for
substantially effortless displacement by edges of highly flexible
web material,
d. said sensing arm being located immediately adjacent the outer
portions of said air nozzle means whereby, at the moments of
sensing, the web material edges are urged into flat and fully
extended relation by the flowing airstreams discharged from said
nozzle means.
6. Apparatus for handling and guiding web materials such as open
width knitted fabric, comprising
a. air nozzle means disposed adjacent at least opposite side edges
of the web material and embracing at least the side edge margins
thereof in straddling relation,
b. said air nozzle means being arranged to direct controlled flows
of air transversely outward over the opposed surfaces of the web
material toward the edge extremities thereof,
c. means to sense the position of the web material, and
d. control means to control the flow of air from said air nozzle
means,
e. said control means operable to adjust the position of the web
relative to said nozzle means.
7. The handling and guiding means of claim 6, further characterized
by
a. the separate air nozzle means being in the structural form of an
elongated U in external configuration, with the legs of the U
closely embracing the side margins of the web material facing
opposing surfaces thereof.
8. The handling and guiding means of claim 7, wherein
a. each of said legs of the U is divided internally to form a first
flow passage for flowing air inward toward the center axis of the
web material and a second flow passage for redirecting the airflow
outwardly toward the edges of the web,
b. said second flow passage terminating in a flow discharge opening
spaced inward from the edge of the web.
9. The method of flattening and centering an advancing web of
highly flexible and distortable material, such as open width
knitted fabric, which comprises
a. mechanically conveying the web material in a forward
direction,
b. at opposite edge margins of the conveyed material, directing
controlled airstreams in a transversely outward direction over
opposed surfaces of the web material to impart a slight widthwise
tension to the web material to place it in flat, full-width
form,
c. continuously monitoring the locations of the edge extremities of
the web material, in the immediate region of the airstreams,
and
d. controlling the relative effectiveness of said airstreams on
said web material in a manner to maintain said web material
substantially continuously centered between predetermined limits.
Description
BACKGROUND OF THE INVENTION
Knitted fabric is particularly characterized by its geometric
instability, in that it is readily distortable under tensions and
other forces normally applied during fabric processing. In
addition, the width and length dimensions of a knitted fabric are
inherently interrelated, such that lengthwise tensions applied to
the fabric during normal processing result not only in elongation
of the fabric but in a corresponding narrowing of the fabric width.
When the fabric is processed in open width form, additional
problems are presented, particularly with regard to stabilization
of fabric geometry and to a tendency for the fabric edges to
curl.
Heretofore, it has proven very difficult to process knitted fabric
in open width form, because of the inability to maintain control
over the geometry of the fabric (i.e., its length and width
dimensions, stitch or loop formation, crossline configuration,
etc.). And, it has been more customary to process the knitted
fabrics in tubular form and thereafter to slit and open the
processed tube. However, processing prior to slitting and opening
results in an "edge crease" in the center of the open width fabric,
which is objectionable in the finished product (e.g., often a
lamination with vinyl) and is very difficult to remove. Because the
edge crease problem is obviated by processing of the fabric in open
width form, there has been an increasing need for processing lines
and equipment suitable to this purpose.
In accordance with the foregoing objectives, the invention provides
a pneumatically operated device for handling and guiding knitted
fabric, most advantageously, in open width form. The new device is
typically located in the processing line before processing
operations such as liquid impregnation and drying of the fabric and
serves to act upon the fabric to maintain it in position for proper
engagement by the downstream processing units. A particularly
advantageous characteristic of the new and improved fabric-guiding
device is the absence of mechanical engagement of the fabric during
fabric handling and alignment and the consequent absence of
undesirable geometric readjustment of the unstable fabric.
SUMMARY OF THE INVENTION
In accordance with a specific aspect of the invention, novel and
improved facilities are provided for initially manipulating to flat
form and initially substantially aligning the flat, open width
knitted fabric. The arrangement is such that the open width fabric,
which is very delicate to handle and which may tend to curl badly
at the edges, is drawn under control from a supply, substantially
centered with respect to the principal axis of the processing line,
and laid flat at the edges for proper threading into the downstream
processing equipment. The new apparatus comprises novel
airflow-directing means located at the opposite margins of the
fabric and operative to direct forcible streams of air laterally
outward along the top and bottom surfaces of the fabric. The
friction between the fabric and the laterally outwardly flowing
airstreams is sufficient to impart a very slight widthwise tension
to the fabric, sufficient to cause it to lie flat and wrinkle-free
and to flatten and at least temporarily uncurl the edge
extremities.
Sensitive edge position sensing means are provided in close coupled
association with each of the above-described air nozzle assemblies
to control the flow of air thereto in response to the position of
the fabric edge. If the fabric tends to be drawn toward the
right-hand side of the line axis, the edge sensing control is
operative to reduce the airflow velocity at the right side nozzle
or nozzles and/or to increase the airflow velocity at the left-hand
nozzle or nozzles, and vice versa. The arrangement is such that an
unbalancing tendency of the fabric in a given lateral direction
relative to the axis of the processing line causes an automatic
correction in the effective airflow velocities to maintain the
fabric in a centered relationship.
The air-actuated manipulating and guiding means is particularly
advantageous in connection with the handling and treatment of open
width knitted fabric, because of the general difficulties of
handling such fabric and initially placing it in flat, wrinkle-free
form without distorting or distending it in some undesirable
manner. By acting on the fabric margins by outwardly flowing
airstreams only, it is possible to avoid all mechanical contact
with the fabric and thus to avoid mechanically distorting the
fabric or acting upon it with greater force than desired at the
particular stage of the processing sequence.
While the air guide arrangement is especially suited for the
guidance of open width knitted fabric in the overall processing
line described herein, it will be appreciated that the inventive
principles thereof will have widespread applicability in other
environments and with other web material.
For a better understanding of the above and other features and
advantages of the invention, reference should be made to the
following detailed description and to the accompanying drawing.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a elevational view of a fabric handling and processing
line incorporating various features of the invention.
FIG. 2 is a cross-sectional view taken generally along line 2--2 of
FIG. 1.
FIG. 3 is an enlarged, fragmentary, cross-sectional view taken
generally along line 3--3 of FIG. 2.
FIG. 4 is an enlarged, fragmentary, cross-sectional view taken
generally along line 4--4 of FIG. 1.
FIG. 5 is a fragmentary, cross-sectional view taken generally along
line 5--5 of FIG. 4.
DESCRIPTION OF PREFERRED EMBODIMENTS OF INVENTION
Referring now to the drawings, and initially to FIG. 1, the
reference numeral 10 designates a supply container for web material
to be processed in accordance with the invention. The web material
11 most advantageously is an open width knitted fabric and will be
assumed to be such in the remainder of this description. However,
it will be understood that at least certain aspects of the present
invention may be applicable to other web materials, including
tubular knitted fabrics, as will appear.
As illustrated in FIG. 1, the open width knitted fabric web 11
advantageously is guided upwardly out of the supply container 10,
through a first-stage fabric handling and guiding system 12 (if
necessary), and over and about an idler roll 13. The guiding and
handling system 12, to be described in detail, functions to
manipulate the fabric web to a substantially flat form and serves
to at least approximately center the fabric web relative to the
principal longitudinal axis of the processing line. After passing
over the guide roller 13, the generally flat web of open width
fabric travels downward to and around a flattening roll 14 and then
through a second-stage fabric handling and guiding system 15 which
is generally similar to the first-stage handling and guiding system
12 located directly above the supply container. The handling and
guiding system 15 acts upon the fabric in a manner to present it in
substantially flat, wrinkle-free form and also substantially
centers the fabric along the axis of the processing line.
As will be understood, the fabric handling and guiding systems 12
and 15 perform similar functions and, in many circumstances, it
might be feasible to eliminate the first system 12. However, for
maximum reliability and accuracy of alignment, it often is
advantageous to provide a pair of spaced handling and guiding
systems, the first being located in a manner to act upon the fabric
as received from the supply container, and the second positioned to
act upon the fabric immediately prior to its entry into the
principal processing apparatus.
In the processing line illustrated in FIG. 1, the spread-flat open
width knitted fabric is advantageously directed through a padding
processor, generally designated by the numeral 16, the fabric
having been decurled immediately in advance thereof, as described
in our copending Pat. application Ser. No. 611,609. The padding
processor may typically consist of three processing rollers 17-19,
arranged to form a reservoir 20 for processing liquid, a first nip
21 for extracting the fabric (if necessary) and a processing nip 22
for padding the processing liquid. The reservoir 20 may be supplied
with a suitable processing solution, such as a "permanent press"
resin, with which the fabric is uniformly impregnated as it passes
through the nip 22. Structurally, the processing pad 16 may be
generally similar to the apparatus described in the S. Cohn et al.
U.S. Pat. No. 3,207,616 and in the E. Cohn et al. U.S. Pat. No.
3,261,184, it being understood that the equipment is, in its most
advantageous form for the purposes of the present invention,
adapted to accommodate and process open width knitted fabric.
The resin-impregnated fabric discharged from the exit side nip 22
of the processing pad 16 is guided upward and about a
speed-controlled roller 24 and thence sinuously about a plurality
of support rollers of a distending or spreading apparatus generally
designated by the numeral 26 which serves to laterally distend the
impregnated fabric to a predetermined, uniform width as described
in detail in our copending application Ser. No. 611,609.
After lateral distention to a predetermined width, the fabric, now
designated by the numeral 27, is discharged over a control roller
28 and guided about an input speed roller 29 for a fabric drying
and/or curing apparatus generally designated by the numeral 30.
Most advantageously, the fabric drying and curing installation may
be constructed in accordance with the S. Cohn et al. U.S. Pat. No.
3,102,006 and/or the S. Cohn et al. U.S. Pat. No. 3,065,551.
In accordance with broader aspects of the invention, the fabric 11,
in its "as received" condition from the supply container 10, is
drawn vertically upward through the handling and guiding device 12
(it being understood, however, that the device 12 may be omitted in
many cases, where adequate guidance is provided by the device 15).
The device 12, as will be described in more detail, serves to
direct controllable airstreams laterally outward over the marginal
edge portions (at least) of the fabric at opposite sides. The
frictional effects of the air flowing laterally outward over the
fabric surfaces tend to impart a very slight widthwise tension to
the fabric, to an extent sufficient to cause the fabric to assume a
generally flat, wrinkle-free form, and also to tend to remove any
"curl" which may tend to appear at the edge extremities of the
fabric, particularly in the case of fabric which has been knitted
in tubular form and subsequently slit and laid open to flat, open
width form. The fabric handling and guiding system 12 also includes
means for sensing the locations of the edge extremities of the
flattened fabric and for regulating the effective force and
velocity of the airstreams in accordance therewith, such that the
flattened fabric web tends automatically to be centered with
respect to the principal axis of the processing line.
The fabric-handling and guiding system 15 functions similarly to
the system 12 but serves to center the flattened fabric more
accurately, by reason of the fact that the incoming fabric is
already approximately centered by the action of the handling and
guiding system 12, and the fabric is again flattened and decurled
in preparation for its entry into the processing system.
With particular reference to FIGS. 2 and 3, the fabric-handling
system 12 is shown to comprise a pair of spaced air nozzle units
31, 32, which may be of generally corresponding construction,
taking into account that the separate units face in opposite
directions. Each of the air nozzle units consists essentially of a
flow nozzle 33, an air blower 34, and a motor 35 for driving the
blower. The opposed nozzle units 31, 32 are mounted on suitable
brackets 36 for transverse sliding movement on a horizontally
disposed traverse bar 37, the latter being suitably secured by
clamp brackets 38 to frame uprights 39. Threaded shafts 40, 41,
typically controlled by means of handwheels 42, 43, are provided to
enable the respective air nozzle units 31, 32 to be independently
adjusted inward and outward of the axis of the processing line to
accommodate fabrics of various initial widths. Normally, the air
nozzle units will be initially adjusted in symmetrical relation to
the line axis, as will be understood.
The second-stage handling and guiding system 15 likewise consists
of an opposed pair of air nozzle units 44, each consisting of a
flow nozzle 45, blower 46, and blower motor 47 (see FIGS. 4 and 5),
all generally similar in construction to the corresponding units of
the first-stage handling system 12. The nozzle units of the
second-stage system 15 are suitably supported by slide brackets 48
on a frame stand 49, for controlled inward and outward adjustment
by means of threaded shafts 50.
With reference now to FIGS. 3-5, the respective airflow nozzles are
shown to comprise a pair of discharge elements 51, 52 arranged in
spaced relation to extend inwardly over the fabric edge margins, in
straddling relation to the fabric web. The separate discharge
elements join to form a common inlet chamber 53, which is in direct
communication with, and advantageously may be structurally
supported by, the discharge outlet 54 of the blower. Each of the
discharge elements includes an outside wall 55 which extends inward
toward the center of the web from the inlet chamber 53, curves
through a 180.degree. arc to form an inner end wall 56, and then
extends outward at 57 a short distance generally parallel to but
spaced slightly from the intended plane of the fabric web 11. The
discharge elements also include inside walls 58 which converge and
join at the inlet chamber 53 and extend inward, toward the axis of
the web, to terminal points beyond the terminal ends of the outer
wall sections 57 but short of the end walls 56. Suitable sidewalls
59, 60 substantially close in the discharge elements, so that each
element defines an air discharge outlet arranged for directing a
controlled low-pressure stream of air at suitable, relatively low
velocity in an outward transverse direction, over the surface of
the fabric. As is evident in FIGS. 3-5, the opposed discharge
elements of each flow nozzle unit are so spaced and arranged that
the discharged airstreams are confined rather closely to the fabric
surfaces over a substantial portion of the length of the nozzles so
that an effective frictional force is applied to the fabric edge
margins.
It will be understood, of course, that the specific nozzle
structure herein illustrated is merely representative of many
possible variations, the significant consideration being that
airstreams are controllably directed over opposed surfaces of the
fabric margins, in a generally outward direction. This will cause
the fabric to more or less float in the opposed airstreams of a
nozzle unit, and a pair of such nozzle units, operating in
conjunction, function in a unique manner to literally float the
fabric and simultaneously apply a slight widthwise tension thereto
at the edge margins, sufficient to manipulate the fabric into a
flat, wrinkle-free full-width form. The fabric is handled in this
most desirable manner without mechanically gripping or otherwise
physically contacting the fabric and therefore without running the
concurrent risk of distorting or marring the fabric. Of particular
importance, the transversely outward flow of low-velocity air over
the fabric edge margins serves as a wholly effective and
advantageous manner to decurl the edge extremities of the fabric,
so that the fabric may subsequently be processed in its fully
extended open width form, free of edge folds or creases resulting
from mechanically engaging the fabric without fully decurling. Of
course, it will be understood that, particularly with respect to
fabrics knitted in tubular form and subsequently slit and opened to
full width, the tendency for the edges to curl may be strong and
recurrent, and "spot" decurling may be required at several stages
of the processing operation.
As a feature of the invention, control means are provided in
conjunction with the respective air nozzle units, or at least one
of them, effective to sense the location of the fabric edge
extremities and to control the air nozzle effectiveness in
accordance therewith in a manner to compensate for any tendency of
the fabric to shift off of the centerline of the equipment line.
FIGS. 4 and 5 illustrate a simplified and advantageous form of
edge-sensing control for the second-stage fabric-handling system
15, which may comprise a suitable mercury switch assembly 61 which
is mounted on the nozzle unit and includes a mercury contact bulb
62 carried by a pivot shaft 63 which is journaled for free
rotational movement through an arc sufficient to make and break the
switch contacts of the mercury bulb 62. In the specific arrangement
shown herein, the shaft 63 extends over the upper one of a pair of
discharge elements and carries a plurality of downwardly extending
edge sensing fingers 64. The unbalanced weight of the sensing
fingers causes them to extend straight downward, normally, but
permits them to be effortlessly displaced outwardly by the fabric
edge 65 (FIG. 4) should it tend to shift too far toward the
outside. During operation, if the fabric should shift off the
centerline, i.e., to the right in FIG. 4, or into the plane of the
paper in FIG. 5, sensing elements 64 will be rotatably displaced in
a counterclockwise direction (FIG. 4), causing a gravitational
shift of the mercury in mercury bulb 62. The switch contacts are
thereby broken, shutting off the blower motor. The consequent
absence of the airflow indicated by the arrows in FIG. 4 eliminates
a force tending to move the fabric to the right and consequently
results in the fabric recentering itself by moving to the left, as
shown in FIG. 4 or out of the plane of the paper as shown in FIG.
5.
Typically, a simplified form of fabric-handling and guiding system
according to the invention includes a sensing switch mechanism
along each edge of the fabric, associated with a blower motor and
arranged to control the speed of the motor in response to positions
of the sensing switch. Typically, the sensing elements are spaced
slightly wider than the fully opened width of the fabric, in a
flat, wrinkle- and curl-free condition, so that a slight tolerance
for widthwise variations is accommodated. However, if the fabric
web wanders beyond the tolerated limits from its intended course,
one of the mercury-sensing switches is actuated to bring about a
relative change in the effectiveness of the opposed air nozzle
units in a manner to return the fabric web to its desired course.
In its most simplified form, the sensing control may be operative
to simply deenergize, or energize the blower motor on the side of
the actuated switch. However, where desired or expedient, more
complex and sophisticated control combinations may be employed,
including means for proportioning the corrective response to the
magnitude of deviation from course, all as will be readily
understood and appreciated by those skilled in the art.
The edge-sensing control arrangements, shown in FIG. 3, for the
first-stage fabric-handling and guiding system, are similar to
those just described, as regards principles of operation, but are
mechanically slightly different to accommodate the fact that the
fabric travels vertically through the first-stage handling system
and horizontally through the second-stage handling system. Thus, in
the arrangement of FIG. 3, a mercury switch 66 is mounted on the
nozzle wall 55 and has its switch bulb (not shown) carried by a
horizontal pivot shaft 67. A swing arm 68 depends from the shaft 67
and carries a plurality of edge-sensing fingers 69 which extend
horizontally through the plane of the fabric web as shown in FIG.
3, the whole system being suitably counterbalanced for relatively
effortless displacement of the sensing fingers 69 by an edge of a
fabric web which wanders laterally from its desired course.
The new and improved fabric-guiding device is particularly
advantageous for use with geometrically unstable fabric, such as
knitted fabrics especially in open width form. The lack of physical
engagement of the fabric by the new device, which is a significant
feature of the invention, eliminates a potential source of
undesirable widthwise reorientation of the fabric which is
characteristic of prior art devices that physically engage the edge
portions of the fabric being processed.
It should be noted that the invention has been described with
regard to a specific preferred embodiment and that many variations
might be made without departing from the inventive concepts
disclosed herein. For instance, the new air guide system could be
arranged to act substantially across the full width of the fabric,
rather than at opposed margins, being so arranged as to direct
airflows outward from the center area of the fabric. However, in
all cases, the airflow advantageously is of low pressure and
velocity, sufficient to guide and control the fabric but not
significantly in excess of these minimum requirements.
* * * * *