Low stress batt folder

An apparatus for folding a fibrous insulation batt having a length and a width is disclosed. The batt has first and second sections, where each section is approximately one half the length of the batt. The apparatus comprises a lower conveyor for conveying folded batts in a first direction, and an upper conveyor which is positioned above the lower conveyor and move in the first direction to define a folded batt exit path. The apparatus further comprises a folding member for folding the insulation batt, where the folding member is adapted to contact the batt across its width. The folding member is mounted for movement to initially push the batt in a second direction, and then subsequently push the batt in the first direction, thereby pushing the batt along the folded batt exit path. The movement of the folding member folds the batt so that the first section of the folded batt is generally parallel to and contacting the second section.

Related copending U.S. application Ser. No. 08/540,629 was filed on even 
date herewith. 
TECHNICAL FIELD 
This invention relates to the folding of a length of a fibrous insulation 
batt. 
BACKGROUND ART 
Fibrous insulation material is typically manufactured in common lengths and 
widths, called insulation batts, to accommodate typical building frame 
structure dimensions. Fibrous insulation batts are commonly made of 
mineral fibers, such as glass fibers, and usually have a density within 
the range of from about 0.2 to about 1.0 pounds per cubic foot (3.2 to 16 
kg/m.sup.3). Typical batt sizes are 16 or 24 inches (40.6 cm or 61.0 cm) 
wide by 8 feet long (2.44 m). These batts can be packaged in various ways. 
The batts can be staggered and rolled together along their lengths so that 
a roll would contain about 10 batts. Alternatively, the batts can be 
stacked on top of each other, compressed and then packaged in plastic 
bags. Because of size constraints it is desirable to fold the batts in 
half along their lengths and stack them together, thereby forming a stack 
which is about 4 feet (1.22 m) long. The invention as described herein 
pertains to the packaging of the folded batts. 
The batts can be folded manually or by a machine, such as the batt folder 
as described in U.S. Pat. No. 4,805,374 to Yawberg. The batts are folded 
by a ram which pushes on the center of the batt to fold the batt into two 
halves. The ram inserts the folded batt between two conveyors. Because of 
the linear movement of the ram, the folded batt has to change from one 
direction to another by the use of multiple conveyor surfaces. This change 
in direction pulls and stretches the fibrous insulation material of the 
batt. The height between the conveyors is small compared to the thickness 
of the batt. The height is small to insure that the batt moves from one 
conveyor to another when the batt changes direction. This small height 
compresses the insulation batt and reduces the recovery thickness after 
the batt is unpackaged. The conveyor height must also be small to 
accommodate the frictional forces exerted by the linear ram when the ram 
retracts back between the compressed surfaces of the batt. These 
frictional forces retard the progress of the batt through the conveyors. 
The detrimental small vertical height between the conveyors assures that 
the ram will not pull the batt backwards as the ram retracts. After the 
ram pushes the batt between the two conveyors, the conveyors grab the 
folded batt and pull the batt towards another set of conveyors which move 
the batt to a packaging machine. The conveyor deposits the folded batt 
horizontally into a packaging machine where the batt is stacked on top of 
other folded batts. The batts are then compressed and packaged into a 
plastic bag. 
It would be desirable to have a method of folding fibrous insulation batts 
which does not put a high level of stress on the batt so that recovery 
thickness is not reduced. 
DISCLOSURE OF INVENTION 
There has now been invented an improved apparatus for folding fibrous 
insulation batts which does not put a high level of stress on the batt so 
that recovery thickness is not reduced. 
The batt folder of the present invention folds fibrous insulation batts 
having a length and a width. The batts have first and second sections, 
where each section is approximately one half the length of the batt. The 
batt folder comprises a lower conveyor and an upper conveyor. The lower 
conveyor conveys the folded batts in a first direction. The upper conveyor 
is positioned above the lower conveyor and moves in the first direction to 
define a folded batt exit path. The batt folder further includes a folding 
member for folding an insulation batt. The folding member is adapted to 
contact the batt across its width, and is mounted for movement to 
initially push the batt in a second direction. The folding member pushes 
the batt first along the second direction and then along the first 
direction, thereby pushing the batt along the folded batt exit path. The 
movement of the folding member folds the batt so that the first section of 
the folded batt is generally parallel to and contacting the second 
section. 
In a specific embodiment of the invention, the folding member can be 
mounted for movement in an arcuate path. The folding member includes a 
pivotally mounted arm having a contact element positioned on the arm for 
contacting and pushing the batt. The contact elements can be comprised of 
rods which extend across the width of the insulation batt. The contact 
elements can be retractably mounted on the arm to enable disengagement of 
the contact member from the folded insulation batt after the batt has been 
pushed into the folded bar exit path. 
In another specific embodiment of the invention, the contact element 
comprises first and second contact elements that are spaced apart and 
adapted to contact the batt across its width and between the first and 
second sections. The movement of the folding member and the two contact 
elements creates two spaced apart folds across the width of the batt as 
the batt is being folded and pushed into the folded batt exit path. The 
first and second contact elements can each be comprised of a pair of rods 
extending partly across the width of the batt so that each pair can be 
retracted from the insulation batt. The rods may also be adjustably 
mounted on the arms to accommodate different batt thicknesses. 
In a specific embodiment of the batt folder, the batt folder comprises a 
curved support plate for supporting the first section of the insulation 
batt prior to folding. In yet another specific embodiment of the batt 
folder, the batt folder comprises a deflector for rotating the first 
section of the batt around the upper conveyor to align the first section 
of the batt generally along the second direction. The deflector can be 
pivotally attached to the folding member so that the pivoting action of 
the folding member causes the deflector to rotate the first section of the 
batt around the upper conveyor to align the first section of the batt 
generally along the second direction.

BEST MODE FOR CARRYING OUT THE INVENTION 
There is illustrated in FIG. 1 a prior art batt folder generally indicated 
at 10, and as described in U.S. Pat. No. 4,805,374 to Yawberg. An unfolded 
fibrous insulation batt 12 is delivered to the batt folder by an upstream 
conveyor 14. Prior to the folding of the insulation batt, the batt can be 
temporarily compressed by a conveyor 15 which is parallel to the upstream 
conveyor 14. The conveyor 15 is raised above the upstream conveyor 14 a 
distance less than the thickness of the batt. The compression "softens" 
the insulation material and reduces the tendency of the folded batt to 
unfold. Softening compresses the insulation product so it is not as stiff 
and does not recover back to its optimum height. Thus, the resistance to 
unfolding is not as great in softened fibers as in unsoftened fibers. The 
softening is not necessary on some types of insulation batts, such as 
those with low density or having small thickness. 
After the batt has been softened, if needed, the batt folder then folds the 
batt and delivers the folded batt by a downstream conveyor 16, moving in a 
first direction 18, to a packaging machine 20. The batt is folded in half 
so that a first section 22 of the batt is lying generally flat and on top 
of a second section 24. The packaging machine includes a stacker 26 which 
stacks the folded batts horizontally until a desired number is reached. 
The stack is then compressed by the stacker and the stack of batts is 
inserted into a plastic bag by a bagging apparatus 28. The packaged batts 
are then ready for final shipping. 
To fold the insulation batt, the batt is delivered by the upstream conveyor 
14 until the unfolded batt is suspended by the upstream conveyor and a 
skid plate 30. The top section of the unfolded batt rests on the skid 
plate and the bottom section rests on the upstream conveyor. A ram 32 is 
linearly driven into the center of the suspended batt and is pushed by the 
ram in a second direction 34. The batt is folded as the ram pushes on the 
center of the batt and forces the batt between an upper conveyor 36 and 
the upstream conveyor 14. The folded batt then changes direction from the 
second direction to the first direction as the folded batt is pulled along 
between the upper conveyor and the downstream conveyor. The batt is 
softened as it travels through the conveyors, and therefore, pre-softening 
by conveyor 15 before folding may be unnecessary. The downstream conveyor 
then delivers the folded batt to the packaging machine. 
Pulling the batt through the changes in direction requires high frictional 
forces between the conveyor surfaces and the batt. To achieve the high 
frictional forces needed to move the batt between the conveyors, high 
compression is required. The height between the downstream conveyor 16 and 
upper conveyor 36 is indicated at h. For example, a 6 inch (15.2 cm) thick 
batt would require a height h within the range of about 2 inches (5.1 cm). 
This high compression and the stretching action which occurs as the 
compressed batt is bent from the second direction to the first direction 
damages the batt. The batt's recovery thickness after it is unpackaged is 
lowered due to the damage caused by the conveyors. 
The batt folder of the present invention is shown in FIG. 2 and generally 
indicated at 40. The unfolded insulation batt 12 is delivered to the batt 
folder by an upstream conveyor 42. Prior to the folding of the batt, the 
batt is optionally softened by roller 44 which is actuated by pneumatic 
cylinder 46. Since the softening decreases the overall recovery height of 
the unpackaged batt, only a small portion of the batt is softened. This 
small portion is defined as a compression zone 48. The compression zone 
extends across the width of the batt and covers the area of the batt which 
is folded and under compression when the batt is in a folded condition. 
The compression zone is located generally in the center of the length of 
batt, between the first and second sections, and preferably has a length 
within the range of from about 4 to about 20 inches (10.2 cm to about 50.8 
cm). 
After being softened, the batt is delivered to the batt folder where the 
batt is folded and conveyed to the packaging machine 20 by a downstream 
conveyor 50. The downstream conveyor moves in a first direction defined as 
an exit path direction 52. 
The first section 22 of the batt is the leading end of the batt as the batt 
moves on top of the upstream conveyor. The second section 24 of the batt 
is the trailing end of the batt. The first and second sections are 
separated by a center section 57. The first and second sections are each 
approximately equal to one half the length of the batt. When the batt is 
folded, the first section will lie on top of the second section so that 
both sections will be generally parallel to each other. The center section 
will be the section of the batt which is folded or creased. The center 
section of the batt is shorter in length compared to the compression zone 
48, because the softened compression zone is preferably slightly longer to 
insure that the entire length of the center section is softened. 
FIGS. 2 through 4 illustrate the sequence of folding the insulation batt by 
the batt folder. As shown in FIG. 2, the batt is being softened in the 
batt's compression zone by the softening roller 44. A portion of the first 
section 54 of the batt is upheld by a curved support plate 58. An upper 
conveyor 60 is positioned underneath the support plate. The upper conveyor 
is moving in the exit path direction 52 and is positioned above the 
downstream conveyor 50. 
As shown in FIG. 3, the batt is pushed up the curved support plate 58 by 
the upstream conveyor 42 until the center section 57 of the batt is 
positioned between the upstream conveyor and the support plate. When the 
center section of the batt is correctly positioned, a pneumatic cylinder 
62 is actuated causing a folding member 64 to rotate about pivot axis 66. 
Broadly, the folding member folds the batt by pushing the center section 
57 of the batt between the upper conveyor 60 and the downstream conveyor 
50. 
In the preferred embodiment, the folding member includes two arms 68 which 
are pivotally mounted about a fixed pivot axis 66. The arms have ends 70 
that travel in an arcuate path 72 about axis 66. Contact elements in the 
form of a pair of rods 74 are retractably mounted at the ends of each arm. 
The rods are the only part of the folding member which contacts the batt. 
The contact elements do not have to be rods, but can be of any shape that 
allows the batt to be folded as the contact elements push on the center of 
the batt. 
Although there are shown two contact elements to create a dual-folded batt, 
the invention will also work equally well with a single contact element to 
create a single-folded batt. The dual-folded batt is preferable over the 
single-folded batt because of the tendency of the dual-folded batt to stay 
folded and remain relatively flat. The two folds reduce the tendency of 
the top section to lift or spring up from the bottom section. By 
distributing the compression of insulation over two folds the batt does 
not have enough springiness to lift the top section above the bottom 
section and the batt is kept folded by the weight of the top section 
alone. Also, the thickness at the folded end is increased so that the 
thickness of the folded batt is more uniform when comparing the folded end 
to the unfolded end, in contrast to a single-folded batt where the two 
ends are not of the same thickness. 
To fold the batt, the unfolded batt is first positioned so that the center 
section of the batt is positioned between the upstream conveyor and the 
support plate, as shown in FIG. 3. When the pneumatic cylinder 62 is 
actuated, the arm travels in the arcuate path 72 and the rods contact the 
center section of the batt. At that moment, the rods are pushing the batt 
in a second direction, a folding direction 76, which is tangent to the 
arcuate path. The rods continue to push the center of the batt in a 
direction tangent to the arcuate path until the pushing direction is 
parallel to the exit path direction 52, as seen in FIG. 4. The rods are 
then retracted in a direction parallel to the width of the batt so that 
the rods no longer contact the batt. The center of the batt is then 
positioned between the upper conveyor 60 and the downstream conveyor 50 
with the two conveyors defining as a folded batt exit path 77. 
Although it is shown that the batt is moved in an arcuate path to move the 
batt from the folding direction 76 to the exit path direction 52, the batt 
can be moved in any other suitable fashion, such as a combination of 
linear movements. It is important to push the batt into the exit path so 
that the conveyors are not performing the actual folding of the batt by 
pulling the first and second sections into the exit path. Pulling on the 
batt by the conveyors, as in the prior art batt folder 10, requires high 
frictional forces which requires high compression between the upper 
conveyor and the downstream conveyor. The batt will be damaged by the 
stretching of the insulation material if the batt is pulled and bent 
around the conveyor surfaces and through direction changes. In the batt 
folder 40 of the present invention, the arm 68 pushes the batt to the exit 
path 77 at generally the same speed as the conveyors to prevent the 
stretching of the insulation material. The batt folder 40 does not need to 
pull the batt into the conveyors because the arm pushes the batt through 
the changes in direction, that is, from the folding direction 76 to the 
exit path direction 52. Because the conveyors do not need to pull the two 
sections of the batt to fold the batt, the batt is subjected to less 
stress. The height h between the downstream conveyor 50 and upper conveyor 
60 can be much larger than the prior art batt folder 10 of FIG. 1. For 
example, the 6 inch (15.2 cm) thick batt when folded to a double width of 
about 12 inches would require a height h of about 2 inches (5.1 cm) for 
the prior art batt folder 10, but the batt folder of the present invention 
40 would only require a height of about 9 inches to about 11 inches (22.9 
cm to about 27.9 cm). 
The reduction of the dependence on friction to fold the batts between the 
conveyors allows the folding process to be more accurate, thereby insuring 
that the first section 22 and second section 24 are more nearly equal in 
length after folding. The variation in lengths of the two sections of the 
folded batt is reduced by about 50% when compared to the prior art batt 
folder 10. Also, the batt folder 40 of the present invention is able to 
fold batts of longer lengths than the prior art batt folder when using the 
same packaging machine. For example, the prior art batt folder was limited 
to batt lengths of 96 inches (2.44 m), but the batt folder of the present 
invention can fold batts having a length up to 105 inches (2.67 m). 
Likewise, thicker batts can be folded because of the reduced dependence on 
friction between the conveyors to fold and pull the batts. Batts having a 
thickness of about 9 inches (22.9 cm) can now be folded, as compared to a 
maximum of about 7 inches (17.8 cm) folded with the prior art batt folder. 
The batt folder includes a deflector 78 for rotating the first section 22 
of the batt around the upper conveyor to align the first section of the 
batt generally along the folding direction 76. Preferably, the deflector 
is pivotally attached to the arm so that rotation of the arm causes the 
deflector to push against the first section of the batt. As best seen in 
FIG. 5, the deflector has two legs 79 which extend from the deflector and 
travel through two slots 80 in the curved support plate 58. 
The movement of the deflector can be seen in FIGS. 2 through 4. In FIG. 2, 
the deflector is in a non-active position and is out of the way so that 
the first section of the batt can slide up the curved support plate 30. 
The support plate is curved to assist in aligning the first section of the 
batt along the folding direction. In FIG. 3, the deflector legs are 
positioned to begin contact with the first section. The deflector will 
eventually extend in such a way as to push the first section so that it is 
generally aligned with the folding direction 76, as indicated by broken 
lines 81, as shown in FIG. 4. The deflector exerts enough force to "throw" 
or push the first section onto the second section, thereby folding the 
batt as the center of the batt is pushed into the exit path by the rods. 
The deflector, therefore, moves the first section of the batt into its 
folded position so that less stress is applied to the batt as the first 
section moves around the upper conveyor. Without the deflector and the 
curved support plate, the inertia of the first section of the batt tends 
to hold it back and forces the first section of the batt to be bent and 
severely stressed as it moves or rotates around the upper conveyor. 
Referring to FIG. 5, the two pairs of retractable rods 74 are shown 
contacting the insulation batt 12 and inserting the batt between the upper 
conveyor 36 and downstream conveyor 50. Each rod is slideably mounted on 
the end of the arm 70 by bushings 82. The rods have ends 84 which are 
fastened to a pair of slide blocks 86. An actuator 88 is mounted on the 
end of each arm and is engaged with the slide blocks. To retract the rods 
from the folded batt, the actuator is actuated to push the slide block in 
a direction away from the batt which pulls the rods away from the batt. 
The retracted slide block is shown by broken lines 90. When the rods are 
retracted, the arm is free to pivot back up to a horizontal position, as 
shown in FIG. 2, for the folding of the next batt. 
The distance between the contact elements or rods can be adjustable to 
accommodate different insulation batt thicknesses. The rods can be 
adjusted in any sufficient manner, such as by threaded or slotted members. 
FIG. 6 illustrates an embodiment of the end 70 of arm 68 which is 
adjustable with respect to the distance d between the rods to accommodate 
different batt thicknesses. A first rod 92 is mounted to the end 70 of the 
arm 68. A second rod 94 is mounted to an extension bracket 96. An actuator 
98 is mounted on the end of the arm and engaged with the extension 
bracket. To change the distance d between the first and second rods, the 
actuator is actuated to move the extension bracket. The end of the second 
rod is slideably engaged with the slide block so that the rods can be 
retracted independently of the position of the extension bracket and 
second rod. 
It will be evident from the foregoing that various modifications can be 
made to this invention. Such, however, are considered as being within the 
scope of the invention. 
INDUSTRIAL APPLICABILITY 
The invention can be useful in the folding of fibrous insulation batts that 
are stacked and packaged together.