Note: Descriptions are shown in the official language in which they were submitted.
37~
BACKGROUND OF INVENTION
Field of the Invention
The present invention relates to an improved
apparatus and a method for applying a fabric material,
preferbly but not exclusively a wire or fiberglass cloth
screen fabric to a rectangular frame having a fabric
peripheral retention groove and securing the fabric
material therein and wherein the apparatus is substantially
entirely automatic.
Description of Prior Art
It is known to apply a cloth material such as a
screen material to a rectangular frame by the use of
substantially automatic machinery as is disclosed, for
example, as disclosed in U.S. Patent 2,695,445. However,
such methods and apparatus have not proven successful due
to various reasons such as inoperability, malfunction,
machine down time, high cost, bulky machinery, and particu-
larly slow operation. Also, with the above referenced
patent, it is necessary to cut sheets of the screening
material with precise dimensions, and if such sheets are
not oriented perfectly over the retention frame, then an
improper assembly results. Also, if the sheet material
sags or has a ripple therein, then it will not be secured
entirely along the retention groove of the frame.
U.S. Patent 2,753,897 teaches a further method of
assembling a screening material to a rectangular frame, and
again in this method the fabric material is cut into sheets
and secured to the frame in a die wherein the sp~ine cord
is pushed into the retention groove of the frame by a
single piston action. Such a machine is very labor inten-
sive as it requires personnel to position the spline cord,
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the screening sheet and the frame into the die and then
actuate the die and remove the screen frame. It is also
necessary to ensure that the screen is entirely flat in the
die cavity and free of ripples. This method is also time
consuming and not commercially feasible.
SUMMARY OF INVENTION
It is a feature of the present invention to
provide an improved method and apparatus for securing a
fabric material to a rectangular frame and which substan-
tially overcornes all of the above-mentioned disadvantages
of the prior art.
It is a further feature of the present invention
to provlde a method and apparatus for securing a wire or
iberglass cloth screen fabric to a rectangular frame and
wherein the apparatus is substantially all automatic and
fast to execute.
Another feature of the present invention is to
provide a method and apparatus for securing a wire cloth
screen fabric to a rectangular frame and wherein the fabrlc
is fed to the frame from a continuous roll and severed
only after the spline cord is applied in the retention
groove of the frame.
Another feature of the present invention is to
:
provide an adjustment means to assure for the parallelism
of the frame members prior to the application of the cloth.
; Another feature of the present invention is to
provide a method and apparatus for securing a wire cloth
screen fabric to a rectangular frame and wherein the frame
corner connections ~are posltioned to their final closed
i3~7~
position with the frame being squared off by the
machine prior to the application of the wire or
fiberglass cloth screen fabric thereto.
Another feature of the present invention is
to provide a method and apparatus for securing a wire
or fiberglass cloth screen fabric to a rectangular
frame and wherein the spline cord is positioned by a
positioner device which is displaced entirely along the
retention groove of the frame and which simultaneously
cuts the wire cloth as it applies the spline cord, and
wherein the speed of the applicator is in the range of
3 to 4 feet per second.
It is a further feature of the present
invention to provide a method and apparatus for
securing a wire cloth screen fabric to a rectangular
frame wherein there is provided an automatic control
device for effecting the entire assembly of the wire or
fiberglass cloth to the rectangular frame while taking
count of the number of frames assembled and the size of
the frames.
According to the above features, from a broad
aspect, the present invention provides an apparatus for
applying a fabric material to a rectangular frame
having~a~fabric retention groove along respective side
members thereof. The apparatus comprises a frame
support struc-ture having a planar frame support surface
which is comprised of two pairs of opposed parallel
frame engaging members. One of the frame engaging
members of each of the pairs is an adjustably
displaceable frame. Each frame engaging member is
further provided with gripping means for cla~ping a
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respective one of the side members of the frame along a
substan-tially straight axis when actuated to a gripping
posi-tion and for releasing the side members when
actuated to a release position. The other ones of the
frame engaging members of each of the said pairs are
stationary and provided with displaceable bars to apply
clamping pressure on the side members of the frame to
ensure proper corner connections. An adjacent end of
the displaceable bars is spaced from one another and
pivotally connected on a flat support plate. The
support plate exceeds a straight frame abutting edge of
the other ones of the frame engaging members to
constitute a frame support surface. The frame abutting
edge extends at right angle to the frame support
surface. Fabric positioning means is provided for
positio~ing a predetermined length of the fabric
material over the frame to overlie the fabric retention
groove of the frame side members. A spline cord
positioner is displaceable in alignment with the
retention grooves for applying a spline cord in the
grooves from above the fabric material to retain the
material in the grooves. Cutting means is further
provided for severing the fabric material from the
frame.
According to another aspect of the present
invention there is provided a method of securing a
fabric material in a retention groove disposed
circumferentially about a rectangular frame by applying
a spline cord in the groove with a fabric portion being
disposed therein. The method comprises storing data in
an electronic controller means with data pertaining to
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the dimensions of a rectangular frame. A frame support
structure having four frame engaging members is
automatically displaced to a frame receiving position. The
frame is then disposed on the frame support structure.
At least two frame engaging members of the frame
support s-tructure are then moved to position side
members of the frame to a desired configuration. The
side members are gripped by gripping means -to maintain
the side members along respective straight transverse
axes. A predetermined length of the fabric material is
then positioned over the frame to overlie the retention
groove in the side members. Engaging means is then
displaced to engage a leading edge portion of the
fabric adjacent dispensing pincer rolls. A retracting
force is applied to the engaging means whereby
dispensing a predetermined length of fabric by
controlling the revolutions of the pincer rolls. The
spline cord positioner is displaced to a predetermined
position on one of the side members of the frame. A
spline cord is then disposed in the groove by
displacing the positioner along the entire length of
the grooves in the side members while forcing the spline
cord in the groove over a portion of fabric.
Simultaneously the fabric is trlmmed adjacent the
spline c~ord which is positioned in the groove. The
spline cord is then severed and the fabric is cut to
disconnect same from a supply of fabrlc. The frame is
then disconnected from the frame support structure.
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BRIEF DESCRIPTION OF DRAWINGS
A preferred embodiment of the present
invention will now be described with reference to the
example thereof as illustrated in the accompanying
drawings, in which:
FIGURE 1 is a simplified top view of the
apparatus showing parts thereof in schematic form;
FIGURE 2 is a perspective view showing the
elements constituting the frame engaging members;
FIGURE 3A is a section view of a stationary
frame engaging member;
FIGURE 3B is a simplified side view showing
the construction of the gripping means;
FIGURE 4 is an enlarged top view of the
corner intersection of the stationary frame engaging
members illustrating the construction of the
displaceable bars and ejectors;
FIGURE 5 is a side view of the jaw member
~ constituting the fabric positioning means;
; : FIGURE 6 is a simplified perspective view
showing the construction of the spline cord positioner
and its bri.dge bar;
~; FIGURE 7 is a simplified fragmented section
view showing the construction of the cord applicator
:head and its posltion relative to the retention groove
of a frame member
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FIGURE 8 is a section view showing the spring
coupling between the inner and outer cylinders of the cord
applicator head of Figure 7;
FIGURE 9 is a schematic view showing the
dispIacement of the cord applicator head along a corner
portion of a rectangular frame;
FIGURE 10 is a schematic perpective view of the
spline cord accumulator mechanism;
FIGURE 11 is a side view of the screen mesh
cutting device;
FIGURE 12 ls a schematic view showing a supply
roll of screen fabric material and its relationship with
respect to the pincer drive rolls and the jaw bar fabric
positioner;
FIGURE 13 is a simplified schematic view illus-
trating a turret frame supply device; and
FIGURES 14A and 14B are fragmented top views
showing two different types of corner connectors for screen
supporting rectangular frames.
DESCRIPTION-OF PREFERRED EMBODIMENTS
Referring now to the drawings, and more particu-
larly to Figure 1, there is shown the fabric applying
apparatus 10 of the present invention for securing a fabric
material 11, herein a wire cloth screen fabric, to a
rectangular frame 12. The rectangular frame 12 is
constructed of four side members with the pair of side
frame members 13 being disposed parallel to one another and
the end pair of transverse side members 14 also disposed
37~
parallel to one another.Each of the side members 13 and 14
are connec-ted at their corners by corner connectors 15 and
15' respectively, as shown in Figures 14A and 14B.
The frame 12 is disposed on a planar frame
support surface which is comprised by two pairs of opposed
parallel frame engaging members 16-19. The frame engaging
members consist of two adjustably displaceable frames 16
and 17 and two stationary frames 18 and 19. These frame
engaging members 16-19 retain the pair of rectangular frame
side members 13 and 14 in a squared off position prior to
the applica-tion of the wire cloth material 11 thereover.
Disposed o~er the Erame engaging members 16~19 is
an elongated jaw bar member 20 which is displaceable to a
"pick up" position ad~acent the end beam structure 21 of
the support structure 9 where the jaw bar member 20 will
engage a leading edge 11' (see Figures S and 12) of the
wire cloth screen fabric 11 and pull same over the frame
side members 13 and 14 so that the fabric material overlies
the retention grooves 13' and 14' of the pairs of side
members 13 and 14.
A spline cord 22 feeds a positioner device 23
which is secured and displaceable along a displaceable
bridge bar 24 whereby to apply the spline cord 22 in the
grooves 13' and 14' of the side:members 13 and 14 and over
the fabric material 11 positioned across the frame, whereby
to retain the fabric material 11 captive within the grooves
13' and 14'. As the spline cord 22 is applied within the
grooves, a trimming knife 25 (see Figure 7) associated with
the positioner 23 severs the screen within the grooves of
the frame side members 13 and 14. At a predetermined
position along the circumferential groove of the frame,
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the spline cord 22 is severed and the positioner
terminates its cord application path. Thereafter, the
positioner head 23 (see Figure 6) is disengaged from the
frame and the bridge bar 24 is moved to the forward end
position 26 of the support structure where a trimming
device 27 attached to bridge 17 ~see Figure 6) engages the
screen material and cuts it along a straight line as the
bridge bar 24 is retracted as required across the support
structure to a rearward end position toward 28. The pincer
rolls 29' (see Flgure 12) then retract the fabric to posi-
tion the leading edye 11' of the screen fabric to a
receiving position for the jaw member to engage in the next
cycle.
As shown in Figure 1, an electronic controller
module 29 is also provided and has a display screen 30 for
displaying various stored informa-tion in the me~ory of the
control device. Keyboards 30l are also provided to enter
information within the control module 29. This module also
controls various circuits and swltches in the control panel
31 to effect the automatic control of the various parts of
the machine~ mounted on the support structure 9. For
example, the module 29 w~ll store data relating to the
dimensions o-f the rectangular :frames, the quantity of the
frames to be assembled, the length of spline cord 22
remalning in~ its storage spool, the length of wire cloth
screen also remaining in it supply spool, etc.
As also shown in Figure 1, an accumulator device
32 is also`provided to accumulate and dispense spline cord
22 to the positioner 23. The construction and operation of
this device will be descrlbed in detail later.
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Referring now to Figures 2 to 4, and 14A and 14B,
there is shown the construction of the Erame engaging
members 16, 17, 18 and 19. Each opposed pair of these
members has a displaceable member and a stationary member
with members 16 and 17 being displaceable, and members 18
and 19 being stationary. The stationary members 18 and 19
are each provided with displaceable flat bars 33 and 34 to
apply clamping pressure on the frame side members to ensure
proper corner connections. The adjacent ends 33' and 34'
of these bars are spaced apart from one another a predeter-
mined distance and pivotally connected at a pivot connec-
tion 33" and 34" to flat support bars 18' and 19'. The
flat support bars extend beyond a straight vertical
abutting edge 35 of each of the plates 33 and 34 to consti-
tute a frame abutting edge surface which extends at right
angles with the top surface of the support bar 18' and 19'.
When the frame side member is positioned on the top surface
of the bar 18' adjacent the abutting edge 35 and the
displaceable frame members 16 and 17 have all moved into
position to close the frame side members at their corner
connections, as shown in Figures 14A and 14B, these
dlspl~aceable bars 33 and 34 will move inwardly in the
direction of arrows 36 whereby to ensure that all the
corner connectors 15~and 15' are properly secured.
The adjustably displaceable frame member 17 is
constituted by a flat bar member 38: having a flat support
surface and a right angle rear plate 39 spaced rearwardly
of the forward edge of the flat support bar 38. ~his
displaceable frame member 17 is interconnected at opposed
ends thereof on a support guide block 37 which is secured
to a respective one of opposed parallel guide rods 40 and
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displaced thereon by drive means in the form of a link belt41 driven by suitable motor means ~not shown). The link
belt provides accurate parallel displacement of the dis-
placeable frame member 17 with respect to the stationary
frame member l9.
The other adjustably displaceable frame 16 is
constituted by a plurality of frame retention blocks 42
which are axially displaceably mounted on the bridge arm 43
whereby to move closer or further away from one another by
means of an accordion link connector 44. This connector
comprises a plurality of pivotally connected bars 45
arranged in a criss-cross manner, as is well in the art.
The accordion connector 44 is also connected to -the other
adjustably displaceable frame 17 which moves at right
angles to the straight bridge arm 43, and by doing so
displaces the retention blocks 42 toward or away from each
other as the frame 17 is displaced. Each of these blocks
42 has a frame support surface 46 and a straight frame
abutting edge 47 extending at right angles to the surface
46.
The straight bridge arm 43 is also secured at
opposed ends thereof to a respective one of opposed guide
:
rods 48 which are~ secured parallel to one another ln
channel members~9' of the support structure 9. The arm 43
is dlsplaceable on these guide rods 48 by drive means which
is also constituted by a pair of link belts 49 driven by
motor means (not shown) whereby to~displace the bridge arm
43 and the blocks 42 in parallel relationship with respect
to the stationary frame engaging member 18.
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637~
In operation, the adjustable frame members 16 and
17 are moved to a frame receiving position which is deter-
mined by the data supplied in the control module 29 and an
opera-tor places a preassembled frame in the condition, as
shown in Figures 14A and 14B, wherein the side members 13
and 14 are not fully engaged with their connectors 15.
This last assembling step is made by the machine as soon as
the operator depresses pedal 50 after the frame is posi-
tioned on the support surfaces of the stationary and
displaceable frame members 16-19. The displaceable frame
members then advance to effect a corner closure of the
partially assembled corner connectors 15 of the frame.
When the displaceable frame members 16 and 17 are
displaced, the side members 13 and 14 will move in the
direction of arrows 51, as shown in Figure 14A. Figure 14B
shows a different corner connectors wherein the ends of the
side meMbers 13 and 14 are squared and the channel por-
tions 13' and 14' are cut at 45 degrees to form an abutment
end and a continuous channel in the corner section of the
frame. The connector 15' is herein shown as an injection
molded plastic corner piece with a square corner portion
15" thereof being exposed.
After the frame is rigidly squared off and
retained by the frame engaging members, a gripping means,
as shown in Figures 3A and 3B, in the form of an ~abutting
nk finger 52 is moved to an engaglng clamping position as
shown in ~igure 3 with the frame side member 15 being
clamped between the abutting straight edge 35 and the
finger element 52 whereby to clamp the side member to
maintain it along a straight axis guided by the abutting
straight edge 35. Accordingly, all of the side members of
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the frame are retained rigidly along straight transverse
axes. The gripping means is a chain link 53 disposed
about a drive sprocket 54 and an idle sprocket 55 whereby
to position the link finger 52 against the frame member 12.
The finger 52 is retracted under the flat support base 18'
when in a nonclamping position. As shown in Figure 2, such
gripping fingers 52 are located at predetermined locations
under the inner edge of the displaceable and stationary
frame engaging members. The gripping means will be acti-
vated only where a frame will be positioned.
Referring to Figures 2 and 4, there is also shown
the provision of ejector pins 56 mounted in the stationary
and displaceable frame engaging members. These ejector
pins are located in a slot cavity (not shown) under the
flat support surfaces 33, 34, 39 and 47 of the stationary
and displaceable frame members and are movable outwardly
along an arc, such as 57 in Figure 4, about a pivot connec-
tion 58. Only a single ejector 56 is provided on the
accordion blocks 42. However, these are provided in a
spaced apart manner along the other frame members to ensure
that an ejector is present when small or large frames are
. .
assembled. For this reason, the ejector pins 56 are located
close to the corner pivot connection of the bars 33 and 34
and also close to the end of the bar 17. These ejector
~ :
pins assure that the frame is released from the stationary
and displaceable frame engaging members for the release of
the frame in the area 59 between these members and onto a
conveyor belt 60 displaceably movable thereunder, whereby
to eject the frame and the screen excess clippings after an
assembly cycle.
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After the frame side members are rigidly held and
positioned and aligned by its planar frame support members,
the plane of which is depicted by numeral 61 in Figure 6,
the elongated jaw bar member 20 (see Figures 1, 5 and 12)
moves to its "pick up" position, as shown in Figure 12,
where the jaws are opened to receive the leading edge o~
the screen material 11 and closed to engage the leading
edge portion 11' of the screen material 11. As shown in
Figure 5, the jaw member comprises a lower stationary jaw
member 62 and a pivoted -top jaw member 63 interconnected by
a hinge member 6~. A chamber 65 is defined between both
members adjacent the hinge member 64 and an in:Elatable -tube
66 is disposed longitudinally in this chamber 65. By
inflating the tube 65 the pivoted jaw member 63 is caused
to move to its position as shown at 63', and namely its
closed position. When the tube 65 is deflated, the pivoted
jaw member 63 rises to its open position, as shown at 63",
due to the counter weight in the rear portion 66 thereof
being heavier than the front portion forwardly of the hinge
pin 67. As soon as the jaw is closed to retain the leading
edge 11' of the materialj the pincer rolls 29 are then
driven by a drive servo motor 68 which is interconnected by
a link belt 69 whereby to release a predetermined amount of
screen material frorn the roll 70 of material contained in
the bin 71. At the same time as the motor 68 is actuated,
a piston means applies a re-tracting force 72, to the
elongated jaw bar member 20 whereby to pull the fabric 11
and maintain it taut but unstretched, whereby to prevent
sagging and rippling therein. As soon as the proper length
of fabric is released by the pincer rolls, the pressure in
the cylinder (not shown~ pushing the jaw member is released
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~637~
and the screen material 11 is positioned to overlap at
least the retention grooves of the side members 13 and 14
of the frame. The spline cord positioner 23 and its
associated bridge bar 24 then moves into position over the
retention groove of the outermost side member, and that is
the one secured to the displaceable frame engaging member
17. Preferably, but not exclusively, this position is at a
predetermined location along one of the side members and
not in the corners of the frame whereby to provide more
rigldity in the corner by eliminating a spline joint at
that position.
Referring now more specifically to Figures 6 to
9, there will be described the construction of the spline
cord positioner 23. As herein shown, the positioner is
provided on a displaceable carriage 72 which is secured to
a guide rail 73' attached to the bridge bar 24. The posi-
tioner 23 has an applicator head 73, a cord guide tube 74,
and cord severing means 75 associated with the cord guide
tube. As shown in Figure 7, a trimming blade element 25 is
also associated with the cord applicator head 73 for
severing the screen fabric 11 in the groove of the frame
side members ad~acent the cord 22 positioned therein.
As shown in Figure 7, the cord appllcator head
comprises a vertically displaceable support cylinder 74
supporting a cord positioning wheel 77 on an axle 77' at a
lower end thereof. A guide channel 78 locates the spline
cord 22 under the wheel 77. A drive wheel 114 holds and
advances the cord 22 in the cylinder 74. An outer
cyllnder 79 is axially rotatable independently of the inner
cylinder and connected to the inner cylinder 74, at its top
periphery by a torsion spring 80 whereby tO position the
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cutting edge 25' of the trimming element 25 at a predeter-
mined location behind the wheel 77 whereby to sever the
screen material 11 in the groove 14' of the frame member
14. The torsion spring 80 also applies pressure on the
cutting edge and permits the blade cutting edge 25' to be
displaced around the corner portions of the frame, such as
shown at 81 in Figure 9, and along the arc 82 as shown in
Figure 8, whereby the blade reassumes its normal blased
position with respect to the planar axis of the wheel 77.
This spring connection 80 is inside the housing 76.
It is po.inted out -that when the wheel reaches the
corner position of a frame, the control module 29 has this
information in memory and automatically causes the inner
cylinder 74 to retract or move upwardly within the outer
cylinder 79 to lift the wheel by means of the friction
coupling of a top extension portion of the inner cylinder
74 which is in friction coupling with a drive wheel 84
which is operated to move the inner cylinder upwardly or
downwardly. The wheel 77 is then rotated by rotating the
inner cylinder 74 which is coupled to motor 83 by a link
belt 85. After the wheel 77 has been oriented at a right
angle:it is -then lowered in the right angle groove 14' of
the adjacent frame side member 14. As soon as the wheel
proceeds from the corner position, the torsion spring 30
has been wound a quarter turn and wiI1 move the cutting
edge ~25 of the blade along the arc 82 as :soon as the
positioner advances whereby to sever the screen material in
the corner portion and reassume its normal position, as
shown in Figure 8.
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The upper portion of the inner cylinder 74 also
constitutes a guide for the spline cord 22 as shown in
Figure 6. Preferably, but not exclusively, the spline cord
22 is also suspended centrally over the frame by a pulley
87 whereby to have minimum distortion and drag on the
spline cord. Before the cord applicator head 73 reaches
its initial starting position along the side frame member
during a spline application cycle, at a predetermined
distance from this position, the extension portion of the
inner cylinder has reassumed its initial axial position. An
opening or sli-t 88 in the cylinder 74 is aligned with a
cutting blade 89 which is act~lated in and out of the
opening 88 by an air cylinder (actuator) 90 whereby to
sever the cord, at a predetermined length whereby the free
end of the cord will terminate very close to the starting
end of the cord within the retention groove of the frame.
After the cord application cycle is terminated, a displace-
able connector block 91 is commanded to move upwardly to
displace the cord applicator head 73 from the frame to
permit the frame and the screen material secured thereto to
be released. It is pointed out that the spline cord is
applied at a speed of 3 to 4 feet per second and that total
assembly time of a frame, of approxlmately 2 feet by 3
feet, would take approximately 20 seconds. Also, the
spline cord is applied about the frame with the ends of the
spline cord lying within a tolerance of 1/8 of an inch from
each other.
Referring now more particularly to Figures 6 and
11, there will be described the operation and construction
of the cutting device 27. After the spline cord positioner
23 has lifted, the bridge bar 24 advances in the direction
1;26~3'7~
of arrow 92 to a screen fabric trimming position. At that
stage of the assembly, the jaw bar 20 still engages the
fabric leading edge and side sections of the fabric, which
have not been cut remain taut with the pincer rolls 29.
The bridge bar is displaceable on a pair of opposed guide
rods 93 through a support coupling 94 at opposed ends of
the bridge bar. The displacement of the carriage 72 is
effected by a link belt 95 which is driven by a motor 96
and all controlled by the control module 29. The cutting
device 27 is also secured to a carriage 97 displaceable on
the guide rod 93 at the feed end of the fabric and is
displaceable relative to the bridge bar 24. A vertically
displaceable coupling 98 is actuable whereby to move the
cutting device 27 along a vertical axis whereby the trim-
ming device may be positioned to receive the side edge of
the fabric material.
As shown in Figure ll the cutting device
comprises a cutting wheel 99 secured to a displaceable
support lO0. A guide plate lOl positions a free edge
portion ll' of the fabric ll elevated from the upper
surface 33' of the movable bar 33 and locates the screen
material on the guide plate and under the cutting wheel 99
whereby to sever same. By retracting the bridge bar 24 the
cutting device is also retracted and the wheel 99 cuts the
~screen entirely across its width. Thereafter, the bridge
bar retracts a predetermined distance, in this partlcular
case 3 inches, and the ejectors 56 are actuated to make
sure that the frame side members are released from their
frame engaging members. The frame engaging member 16
having the blocks 42 is then retracted and the assembled
frame and screen clippings ~all on the lower conveyor 60.
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As previously described, the spline cord posi-
tioner opera-tes very quickly and therefore minimum drag and
resistance in the spline cord is desired. For this
purpose, there is provided a cord accumulator 102, as shown
in Figure 10. The cord accumulator permits a predetermined
length of spline cord 22 to be applied by the positioner
device 23 without having to dispense the spline cord from a
storage spool 103 where considerable resistance to pulling
would be present due to friction and the weight o the
roll. The cord accumulator 102 comprises a pair o spaced
apart guide rolls, herein a lower vertically displaceable
roll 104 and a stationary upper roll 105. The lower roll
104 is vertically displaceable along a guide track 106
secured to the vertical side members 9" of the support
structure 9. As herein shown, there are various loops of
spline cord 22 wound about these rolls, and the number of
these loops is calculated to provide an ample storage
length of the cord to permit the positioner to apply the
spline cord without the need o~ pulling or having to
simultaneously dispense cord from the storage spool 103.
As soon as the cord begins to be dispensed by the posi-
tioner 23, the lower roll 104 moves upwardly along its
guide track 106 and the spline cord is dispensed quickly
with minimum resistance.
As soon as the positioner is lifted from the
frame~ member, a~ter t~he application cycle of the spline
cord is terminated, a cord dispensing drive device 107 is
actuated to rotate its drive wheels 108 which dispense a
predetermlned quantlty spline cord 22. As the spline cord
is dispensed, the weight o the lower roll 104 (which is
~airly light) causes the roll to move downward and to store
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the spline cord about both rolls. As soon as the lower
roll has reached a prede-termined lower position, a stop
switch 109 is activated by the roll support whereby to stop
the dispensing drive device 102. A further switch 110 is
located below the stop switch 109 and this switch is
activated should the spline cord 22 be accidentally
released from ~he cord positioner 23, or for any other
reason, break. Once the lower spool 104 touches the switch
110, the operation of the device stops and an alarm is
actuated. A foot pedal 111 is also provided for threading
the spline cord 22 through the cord dispensing drive wheels
108 when a new spool 103 is positioned on the spool support
shaft 112: A length of spline cord is threaded about the
rolls 104 and 105, the gulde pulley 113, and the suspension
pulley 87, and back into the positioner 23. The spline
cord is prevented from being withdrawn by the cord engaging
drive wheel 114 associated with the cylinder 74.
Referring now to Figure 13, there is illustrated
a modification of the supply end of the machine and wherein
a plurality of rolls 70 of screen fabric may be supported
on a turret frame 115 about a support shaft 116 whereby to
selectively position a predetermined one of the rolls 70
for supplylng the pincer rolls 29. These various rolls 70
may, for instance, be of varying widths or be of the same
widths but arranged on this turret frame for ~uick connec-
tion to the machine to provide minimum machine down time in
interchanging fabric rolls. It is also within the ambit of
the present invention to provide different types of fabric
such as for the fabrication of silk screens ox even provide
plastic film materials, such as polyethylene to assemble
plastic insulation frames. The material could also be
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.
applied to bo-th sides of the frames by providing a frame
with opposed grooves, and not necessarily aligned. The
assembled frame, with one sheet secured thereto, may be
repositioned in reverse onto the frame engaging members for
the application of the second sheet on the opposed side of
the frame. All that is necessary to do to effect such an
operation is to program this information into the control
module 29 and the machine will automatically adjust for a
different location of the retention groove and length of
spline cord.
It is within the ambit of the present invention
to cover any other obvious modifications of the preEerred
embodiment described herein, provided such modifications
fall within the scope of the appended claims.
:
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