Pleating method and apparatus

An apparatus for forming pleats in fabric includes a vertically movable head which can accommodate one centrally located rod, or alternatively, two spaced apart rods. One rod is used to form two pleats and the rod is movable towards a work surface to a position where the rod traps fabric between a work surface and the rod. Two gripping arms are laterally movable and grip the fabric and move towards the central rod. If three pleats are desired, the two spaced apart rods are used, and a vertically movable blade positioned below the work surface can be actuated, which moves the blade upwardly intermediate the two spaced apart rods, carrying the fabric with it, forming a first pleat. The same laterally movable arms can be actuated which grip the fabric and move it inwardly towards the central rod, to form the other two pleats.

BACKGROUND OF THE INVENTION 
The invention relates to a method and an apparatus for forming pleats in 
compliant material, such as drapery material or the like. 
Pleats are usually formed by hand, by a sewing machine operator, and then 
sewn into place on the machine. The material can be quite thick and stiff, 
particularly if it is lined, and the operator must gauge the depth of the 
pleats, fold the material and try to keep that dimension constant in each 
pleat, and then sew (or otherwise secure) the pleats into final position. 
Obviously, the more tucks or folds there are in each pleat, the more 
cumbersome and difficult this operation becomes, requiring considerable 
dexterity and digital strength, and encountering frustration if the 
operator loses grasp of the manually formed pleats in the process of 
forming them. 
One apparatus presently exists including fingers which interengage from 
opposite sides of the material to gather the material and form the pleats. 
While this apparatus is capable of forming the pleats, this apparatus may 
be difficult to operate as the centerline of the pleats may move during 
the formation of the pleat. As the fingers interlock from opposite sides 
of the material, more material may be drawn from one side of the center 
finger than the other, causing the center of the pleat to laterally shift 
during the interlocking phase. This could be a time consuming project as 
the pleat must be unfolded and again pleated. It is necessary to 
accurately position the pleat centerlines, as the cosmetic appearance of 
the completed drapery is dependent upon their position, as the pleats are 
used to retain hooks upon which the drapes are hung. 
SUMMARY OF THE INVENTION 
The present invention provides a mechanically assisted method of forming 
pleats uniformly, and an apparatus for forming pleats to be secured by an 
operator. A predetermined length of material border, such as the upper 
edge of a drapery to be pleated, is placed upon a supporting surface and 
the center of the pleat is clamped to the surface, by one or more 
cantilever supported central bars extending perpendicularly to the edge of 
the material. A pair of complementary cantilever supported side arms, 
extending parallel to the central bar(s), are brought into contact with 
the material at a predetermined distance to each side of the central 
bar(s). 
In making a double pleat, a single central bar is used, and the side arms 
are then moved toward the central bar until the material between the side 
arms and the central bar folds up from the surface and the thickness of 
the material effectively impedes the centering motion of the side bars. 
The depth of the fold is one half the distance traversed by the side bars. 
The operator then grasps the bunched material and simply pulls it forward 
off the open or free ends of the bars, and moves the folded material into 
the head of a sewing machine, or some equivalent device for securing the 
pleat fold together. 
When making a triple pleat, two side-by-side bars are used, extending in 
closely horizontally spaced position, and a central vertically movable 
blade, normally retracted into the support surface at the center of the 
apparatus, first moves upward to carry material up a predetermined 
distance between the central bars, thus forming the center of the three 
folds. The extent of this lifting motion determines the depth of the 
central pleat fold. Then the side arms are engaged with the material and 
moved inward, to form the two outer folds. The extent of the side arm 
lateral movement is selected to form pleats equal in depth to the central 
one. The operator can then withdraw the triple folded portion from the 
apparatus, and proceed to secure the pleat, as in a sewing machine or 
other suitable device. 
In a semi-automatic form of apparatus, according to the invention, motion 
of the various cantilever mounted bars, and of the vertically movable 
central plate when used, is controlled by a foot operated treadle which 
progressively engages a plurality of switches. These switches in turn 
actuate linear motion devices, such as pneumatic cylinders, to raise and 
lower the central bar(s), raise and lower the folding plate when used, and 
to both raise and lower and to move laterally the side arms. The control 
circuit for this apparatus is straightforward and can be switched between 
the different cycles necessary to form double or triple pleat folds as 
described. Also, adjustable mounting is provided for the cylinders 
controlling lateral motion of the side bars, and for the stroke of a 
cylinder controlling the raising and lowering of the central fold plate, 
to vary the depth of the folds in the pleats. The cantilever mounting for 
the central bars includes appropriately placed sockets and quick-connect 
fastening, so the change between a single and a double central bar 
configuration can be accomplished quickly, without use of tools. 
Accordingly, the principal object of the invention is to provide a novel 
method of forming pleats in compliant material; to provide such a method 
which is mechanically assisted to assure uniformity of successively formed 
pleats; to minimize operator fatigue in a pleating operation; to provide a 
pleat folding apparatus which is cycle controlled and forms uniform pleats 
of predetermined yet adjustable dimensions; to provide a pleat 
forming/folding apparatus with cycle adjustment and optionally used parts 
so as to selectively fold at least double and triple fold pleats. 
Other objects and advantages of the invention will be apparent from the 
following description, the accompanying drawings and the appended claims.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
With reference first to FIG. 1, an apparatus is shown generally at 10 for 
forming either double or triple pleats in fabric materials, such as for 
curtains or drapes. The apparatus 10 generally comprises an upper work 
surface 12 supported by an L-bracket 14 which in turn is supported by 
vertical uprights 16. The vertical uprights 16 are held in position by a 
cross-brace 18 which can be supported to a further working apparatus, 
preferably a sewing machine (not shown), via L-bracket 20. The positioning 
of the apparatus 10 relative to the sewing machine is via the elongate 
slots 22 (FIG. 2) in the vertical upright 16, and the elongate slots 24 in 
the L-bracket 20. The apparatus 10 further comprises a head member 26 
vertically movable under the operation of an air cylinder 28 (FIG. 2) and 
a central blade portion 30, which is normally positioned below the upper 
work surface 12, and is operational by means of an air cylinder 32 (FIG. 
1). As shown in FIG. 1, the vertically movable head 26 includes three 
side-by-side apertures, a center aperture 34 which is aligned with a 
central slot 36 (FIG. 2) through the upper work surface 12, and two 
apertures 38 which span the central slot 36. As will be explained more 
fully herein, the head member 26 can either carry two rods 40 which span 
the slot 36 (FIGS. 1 and 2) or can carry a single rod 40 which is aligned 
with the slot 36 (FIG. 3). As also shown in FIGS. 1 and 2, the apparatus 
further comprises gripping arms 42 which are pivotal at 43 via air 
cylinders 44, thereby moving the arms 42 toward and away from the upper 
work surface 12, and are laterally movable via air cylinders 46. While the 
apparatus will be described in greater detail hereafter, the general 
function of the machine will now be described diagrammatically with 
reference to FIGS. 5 through 9. 
As mentioned above, the apparatus 10 is interchangeable for alternatively 
producing either two or three pleats in fabric material. With reference 
first to FIG. 4, the function of the apparatus will be described where two 
pleats are desired. A piece of fabric shown generally at 50 is positioned 
on top of the work surface 12 with a center of the desired pleat aligned 
with a single central rod 40 positioned in the central opening 34 in the 
vertically movable head 26. Also when two pleats are required, the lower 
blade 30 is disabled and is in a fixed vertical position below the upper 
work surface 12 as shown in FIG. 3. After the fabric 50 is positioned on 
the upper work surface 12, the central cylinder 28 is actuated which moves 
the central rod 40 downwardly to a clamping position as shown in FIG. 5A 
to retain the fabric from laterally shifting during the operation. As also 
shown in FIG. 4A, the gripping arms 42 are also vertically movable 
downwardly to a position where they grip the fabric as shown in FIG. 5B, 
and are thereafter moved laterally inwardly towards each other and towards 
the central clamping rod 40 thereby gathering and folding the material 52 
to provide two pleats shown generally at 52. The height of the pleat is 
equal to one-half the distance between the center rod 40 and the side arms 
42. The two pleats can then be grasped by the operator and stitched, as 
indicated at 54, 56, to affix the two pleats, as shown in FIG. 6. 
With reference now to FIG. 7, if three pleats are desired, the apparatus is 
configured with two rods 40 positioned in the two openings 38 spanning the 
central slot 36, and the blade member 30 is vertically actuable. The 
operation begins with the two rods 40 pressing against the fabric as shown 
in FIG. 8A. The rods 40 do not clamp the material tightly to the surface 
12, but rather only press against the fabric sufficiently to prevent the 
material from laterally shift during the lateral gathering of the pleats. 
The blade member 30 is thereafter vertically movable upwardly through the 
slot 36 intermediate the two rods 40, carrying with it the material 50 as 
shown in FIG. 8B. After the blade member 30 has moved upwardly through the 
slot 36 to the height of the pleat 58, the gripping arms 42 are moved 
vertically downwardly as shown in FIG. 8B and then laterally inwardly as 
shown in FIG. 8C to define two further pleats 60 on opposite sides of the 
central pleat 58. The three pleats can then be removed from the apparatus 
and stitched at 62 and 64 fixing the three pleats in the fabric. 
With reference again to FIGS. 1 and 2, the apparatus 10 will be described 
in greater detail. As shown best in FIG. 2, the vertically movable head 26 
is pinned at 66 by pins 68, which are pinned at their opposite ends to a 
vertically movable block 70. The block 70 is pinned at 72 to the rod (not 
shown) of the air cylinder 28. Both blocks 26 and 70 are movable relative 
to an L-shaped block 74 which includes vertically oriented apertures which 
receive the vertical pins 68 in close tolerance through apertures in an 
L-shaped block 74 which in turn is retained to the vertical portion of the 
angle bracket 14. The body of the air cylinder 28 is held by brackets 76 
which are also connected to the L-bracket 14. As shown best in FIG. 2, two 
guide rods 80 extend through apertures 82 of the L-shaped block 74 and are 
laterally fixed thereto, for example, by snap rings (not shown). The guide 
rods 80 extend the length of the work surface 12 and extend through 
apertures 84 in end posts 86, also fixed to the L-bracket 14. 
With reference still to FIG. 2, a central threaded shaft or worm 90 also 
extends through an aperture 92 of the L-bracket 74 and is laterally fixed 
via means such as snap rings (not shown), but is not threaded to the 
aperture 92, so as to be rotatable within the aperture 92. The worm 90 
spans the length of the upper work surface 12 and extends through 
apertures 94 in the end posts 86 and clears the apertures 94 so as to be 
freely rotatable therein. The worm 90 includes a knob 97 positioned at 
both ends for the manual rotation of the worm 90. 
As shown in FIG. 2, the worm has two threaded portions 90a and 90b where 
the threaded portions are oppositely directed, that is, threaded portion 
90a is a right-hand thread whereas the threaded portion 90b is a left-hand 
thread. The threaded portion 90b is cooperable with threaded blocks 96a 
and 96b having threaded apertures 98a and 98b therethrough which upon 
rotation of the worm 90 causes the lateral movement of the blocks 96a and 
96b towards and away from the center L-shaped block 74. The blocks 98a and 
98b further include guide apertures 100 which are slidable along the two 
guide rods 80 to prevent the blocks 96a and 96b from binding on the 
respective worm gear portions 90a and 90b. A bracket member 102 is fixed 
to each of the blocks 96a and 96b, where the air cylinder 46 is attached 
to the bracket 102 via a fastener, such as 104. The air cylinders 46 each 
have a clevis 106 fixed to their rod ends (not shown) and are pinned at 
108 to a bracket 110 fixed to a movable block portion 112 which are 
slidable along the rods 80 via apertures 114. The block 112 also includes 
an aperture 116 therethrough which is profiled larger than the worm 90 to 
allow the worm to rotate therein. With reference still to FIG. 2, the 
block member 112 includes an upper slot 120 having a rocker arm 122 pinned 
at 124 where one end 126 is pinned to the gripper arm 42 and the second 
end 128 is pinned to a clevis 130 which in turn is connected to the rod 
132 of the air cylinder 44. Finally, with reference to FIG. 1, the air 
cylinder 32 is connected to an L-bracket 136 fixed relative to the upper 
support surface 12. The air cylinder 32 includes a cylinder rod 138 fixed 
to a slotted bar 140 which carries the blade member 30. 
With reference now to FIGS. 1 through 3, the operation of the apparatus 
will be described in greater detail. With reference first to FIG. 3, if 
two pleats are desired, the blade 30 is disengaged and one single rod 40 
is positioned in the central aperture 34. As shown in FIG. 1, the head 26 
includes spring loaded ball detents 141 which spring load against a recess 
(not shown) at the ends of the rods 40 to retain and accurately position 
the rods in place. The apparatus 10 is configured for operation with the 
vertical head 26 in its fully upright position with the rod 40 spaced 
above the upper work surface 12, as shown in FIG. 3. The fabric can now be 
inserted beneath the rod 40 and the gripping arms 42, such that the center 
of the desired pleats is laterally aligned with the rod 40. The head 26 is 
now activated thereby lowering the rod 40, clamping the fabric to the 
upper work surface 12. The cylinders 44 are now activated causing the arms 
122 to pivot about pins 124 thereby forcing the gripping arms 42 against 
the fabric. The cylinders 46 can now be actuated which, through the clevis 
106, operates to laterally move both carriages 112 towards the center 
clock 74 carrying with it the fabric in a folded-over manner, as shown 
diagrammatically in FIG. 5C. The height of the pleats can be easily varied 
by way of the rotatable knob 97 which rotates the worm gear 90 thereby 
moving the threaded blocks 96a and 96b and the gripping arms 42, towards 
or away from the center block 74. 
To operate the apparatus 10 to provide three pleats, the rods 40 are 
positioned in the apertures 38 spanning the slot, while the aperture 34 is 
left blank. With the two rods and the gripping arms 42 spaced above the 
upper work surface 12, the fabric is insertable onto the work surface 12 
such that the center line of the pleats is intermediate the two rods 40. 
The operation begins with the lowering of the movable head 26 which 
presses the fabric against the upper work surface 12 and the cylinder 32 
is thereafter activated bringing the blade through the slot 36 which draws 
a portion of the fabric beneath the rods 40 defining a first upstanding 
pleat. It should be appreciated that the rods are held against the fabric 
so as to resist the lateral movement of the fabric but to allow the fabric 
to slide through the rods upon extension of the blade. The gripping arms 
42 are thereafter lowered, through the actuation of the cylinders 44, to a 
position where they are contacting the fabric and the cylinders 46 are 
thereafter operated to laterally move the gripping arms inwardly towards 
the blade 30 defining pleats on opposite sides of the first pleat formed 
by the blade 30. 
Once again, the pleats can be adjusted in height by the raising and 
lowering of the blade, and through the use of the work gear which 
laterally spaces the gripping arms 42 from the center blade 30. As shown 
in FIG. 1A, the air cylinder 32 includes a double ended rod 138 having a 
portion 138a extending from the upper portion of the cylinder body and 
which is connected to the blade 30. At the opposite end of the cylinder 
body, a rod portion 138b extends rearwardly, but is continuous with the 
rod portion 138a so as to move longitudinally therewith. The rod portion 
138b is normally enclosed by the cover 142 as shown in FIG. 1. The rod 
portion has affixed thereto, a split collar 143 which can be moved along 
the rod portion 138b and resecured at a new position, to change the 
maximum height of the blade portion 30, and thereby change the height of 
the middle pleat to correspond to the height of the outer pleats. 
The pneumatic sequencing of the apparatus will now be explained by way of 
reference to the schematic of FIG. 10. The sequencing of the apparatus is 
generally controlled by a foot treadle shown generally at 148 in FIG. 11 
carrying pneumatic limit switches 150, 151, and 152, also shown 
schematically in FIG. 10. As shown in FIG. 10, a supply line 154 supplies 
pneumatic pressure to a manifold 156 having a plurality of output supply 
lines 158a-158f. A supply line 158a feeds two control valves 160 and 162 
where the valve 160 controls the vertical movement of the blade 30, and 
the control valve 162 controls the center vertical head 26. Both of the 
control valves 160 and 162 are pilot operated and spring returned. Limit 
switch 151 receives a supply signal through line 158b which, when 
activated by way of the foot treadle, sends this signal through line 164 
thereby acting as the pilot to operate the valve 162 and lowering the air 
cylinder 28 and the rod 40. 
The air cylinder 32 which operates the blade is also operated through the 
first limit switch, however, the blade is sequenced to operate after the 
complete cycling of the air cylinder 28. A T-connection off of line 164 
presents a signal through 166 to a threshold not 168 which measures the 
pressure across the air cylinder 28. When the back pressure on the back 
side of the air cylinder 28 is at atmospheric pressure (when the air 
cylinder is in its fully retracted position), the threshold not 168 allows 
a pilot signal through lines 170 and 172 to the valve 174. If the 
apparatus is in the two pleat mode, the valve is in the OFF position and 
the pilot signal stops at the valve 174 and the blade is not activated. If 
the apparatus is in the three-pleat mode, however, the valve 174 is in the 
ON position and the pilot signal through line 172 passes through the valve 
174 and acts as a pilot signal through line 176 to the pilot operated 
valve 160 thereby sending the pneumatic signal through line 178 thereby 
raising the air cylinder 32 and the blade 30. 
Limit switch 150 operates the air cylinders 44 and 46 and when the limit 
switch 150 is activated, a supply signal through line 158e is supplied to 
line 180 which acts as a pilot to valve 182 thereby activating the air 
cylinders 44 through pneumatic pressure through the line 184. A threshold 
NOT sensor 186 senses the differential pressure across the air cylinders 
44 by connections at 187 and 188 and when the pressure across the cylinder 
is equalized (when the cylinders are in their fully retracted position), 
the threshold NOT sensor 186 sends a pilot signal at 189 to a double pilot 
three-way valve 190, which receives a supply signal through line 158c, 
thereby sending a supply signal through line 192 to operate the air 
cylinders 49 to move the gripping arms 42 laterally inward. 
To reset the entire system, the foot treadle is pivoted in the opposite 
sense to activate the pilot switch 152 which sends a supply signal from 
line 158d through to line 194 thereby activating the opposite side of the 
double pilot three-way valve 190 causing a signal through line 196 
retracting the arms to their laterally spread position. As the treadle is 
moved to the pivoted position, the switches 150 and 151 are also released 
causing the valves 160, 162, and 182 to spring return thereby causing the 
retraction of the rods of the air cylinders 28 and 32, and the extension 
of the rods of the air cylinders 44. 
While the method herein described, and the form of apparatus for carrying 
out this method into effect, constitute preferred embodiments of this 
invention, it is to be understood that the invention is not limited to 
this precise method and form of apparatus, and that changes may be made in 
either without departing from the scope of the invention, which is defined 
in the appended claims.