U.S. patent number 3,839,122 [Application Number 05/268,393] was granted by the patent office on 1974-10-01 for apparatus for feeding and wrapping sheet material.
This patent grant is currently assigned to Johns-Manville Corporation. Invention is credited to John Marvin Current, Rodney Roger Smalley.
United States Patent |
3,839,122 |
Current , et al. |
October 1, 1974 |
APPARATUS FOR FEEDING AND WRAPPING SHEET MATERIAL
Abstract
Tubes of fibrous, thermal insulation are jacketed with sheet
material by adhering the material to the tubes over a major portion
of their surface while leaving an exposed longitudinal sector of
the wall free of jacketing. The exposed sector is slit to enable
the cylinders to be fitted on pipes. A tab extension of the jacket,
free of the exposed sector and extending thereacross, enables the
mounted tubes to be sealed by adhesive bonding of the tab across
the slit. Precut sheets coated with a dormant and activatable
adhesive are individually removed from a stack, conveyed across a
region in which selected regions of the adhesive in the sheet are
activated, conveyed across a reaction region and conveyed to a
station in which individual insulation tubes are rolled across each
sheet to pick up the tackey surfaced portion thereof. Tubes wrapped
with the sheet can be conveyed to a slitter which registers the
exposed sector with the slitter blade and advances the sector into
the blade longitudinally to sever one wall of the tube.
Inventors: |
Current; John Marvin (Terry
City, OH), Smalley; Rodney Roger (Holland, OH) |
Assignee: |
Johns-Manville Corporation (New
York, NY)
|
Family
ID: |
26671949 |
Appl.
No.: |
05/268,393 |
Filed: |
July 3, 1972 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
3598 |
Jan 19, 1970 |
3693965 |
|
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Current U.S.
Class: |
156/351; 83/54;
156/357; 156/364; 156/446; 156/450; 156/458 |
Current CPC
Class: |
B65B
11/04 (20130101); Y10T 83/0596 (20150401) |
Current International
Class: |
B65B
11/04 (20060101); B65B 11/02 (20060101); B32b
031/00 () |
Field of
Search: |
;271/11,57,107
;118/2,3,8 ;156/356,357,446-458,351,361-364,366,367,DIG.11
;83/54 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Drummond; Douglas J.
Assistant Examiner: Simmons; David A.
Attorney, Agent or Firm: McKinney; John A. Krone; Robert M.
Lister; John D.
Parent Case Text
This is a Division of application Ser. No. 3,598, filed Jan. 19,
1970, now U.S. Pat. No. 3,695,965.
Claims
1. Apparatus for jacketing a cylindrical body comprising a fluid
applicator; advancing means for advancing jacket material past said
fluid applicator; means for selectively activating said applicator
in coordination with the advance of said jacket material to produce
a tacky surface on said material; conveying means for conveying
said tacky surface jacket material to a jacketing station;
orienting means for orienting said cylindrical body to be jacketed
on said conveying means with its length normal to the advance of
said jacket material by said conveying means and in advance of said
jacket material, said orienting means including holding means in
the path of said cylindrical body on said conveying means which
bars the advance of said cylindrical body on said conveying means
until said body has its length oriented transverse of said
conveying means, and controls for withdrawing said holding means
from the path of said cylindrical body to permit the advance of
said cylindrical body on said conveying means; sensing means to
sense the advance of said jacket material to a given position on
said conveying means and to actuate said controls in response to
said advance to said given position to cause the withdrawal of said
holding means whereby said conveying means advances said jacket
material and said cylindrical body to said jacketing station for
wrapping of said jacket material around said cylindrical body; and
said jacketing station including means to roll said cylindrical
body
2. Apparatus for jacketing a cylindrical body according to claim 1
wherein said jacket material has been precoated with a deactivated
and reactivatable adhesive and including a reservoir for a solvent
for said
3. Apparatus according to claim 1 including means to sense the
position of said jacket material along said advancing means; and
control means for actuating said means for activating said
applicator according to said
4. Apparatus according to claim 3 wherein said position sensing
means comprises a pair of sensing means spaced along said path in
advance of said applicator a distance corresponding to the length
of a tab of jacketing material which is to extend from the body;
and means responsive to a coincidence of the response of said pair
of sensing means for actuating said control to its actuating mode
and responsive to an absence of coincidence of response to actuate
said control to a deactuating mode.
5. Apparatus according to claim 1 including a magazine for stacked
sheets of jacket material; means to separate individual sheets from
said stack;
6. Apparatus according to claim 5 including a control for actuating
said
7. Apparatus according to claim 5 wherein said separating means
comprises a vacuum pickup; a mounting for moving said pickup from a
first location remote from said advancing means to a second
location adjacent said advancing means; an elevator for said
magazine to raise the top sheet of said stack to said pickup when
said pickup is in its first location; and coordinated controls for
said elevator and said pickup mounting to raise said elevator and
then transfer said mounting from its first to its second
8. Apparatus according to claim 1 wherein said advancing means
comprises first and second flexible endless belts positioned to
have opposed parallel, essentially coplanar runs and driven at the
same speed; whereby jacketing material in sheet form is
frictionally engaged on opposite faces
9. Apparatus according to claim 1 wherein the jacketing material is
in rectangular sheet form having a width dimension generally
corresponding to the length of the cylinder to be jacketed and a
length exceeding the circumference of the cylinder including a
control for said applicator for activating said applicator as a
sheet enters its effective range and for deactivating said
applicator when fluid has been applied to a length of
10. Apparatus according to claim 1 wherein said conveying means is
a continuous belt underlying said jacketing material and wherein
said applicator is oriented to coat the upper surface of said
jacketing
11. Apparatus according to claim 1 including a magazine for
containing a supply of said cylindrical bodies; and transfer means
for individually transferring said cylindrical bodies from said
magazine to said conveying
12. Apparatus according to claim 1 including a ramp for
successively feeding the cylindrical bodies from said magazine; a
stop limiting the advance of said cylindrical bodies on said ramp;
said transfer means being responsive to said jacket material
advance sensing means for releasing one of said cylindrical bodies
at a time from said ramp to said conveying
13. Apparatus according to claim 1 including means to reclose said
holding means; and sensing means responsive to the passage of a
trailing edge of
14. Apparatus according to claim 13 wherein said orienting means is
actuated in response to the reclosure of said holding means whereby
a body is oriented on said conveying means following the release
for advance by
15. Apparatus for jacketing a cylindrical body comprising a fluid
applicator; means for advancing jacket material relative to said
fluid applicator; means for selectively activating said applicator
in coordination with the advance of said jacket material to produce
a tacky surface on said jacket material and for restricting the
tacky adhesive coating on said jacket material to a region of a
length less than the circumference of the cylindrical body; a
station for wrapping said jacket material around said body; means
to convey said tacky surface jacket material to said station; means
to cause a tab of jacketing material to extend from said
cylindrical body adjacent a region to which said jacketing material
has been adhered; a slitter for said body adapted to cut through a
wall thereof and form a longitudinally extending slit in said body;
means to orient said cylindrical body and said tab with respect to
said slitter to align the unjacketed body portion between said tab
and the region of said jacket material adhered to said cylindrical
body and means to advance said cylindrical body longitudinally
relative to said slitter while maintaining said orientation whereby
said unjacketed body portion between said tab and said adhered
region of said jacket material
16. A combination according to claim 15 wherein said advancing
means is a pair of continuous belts having closely spaced runs
generally at right angles to each other to form a trough for the
reception of the cylindrical body, said trough extending at right
angles to the direction of advance of
17. A combination according to claim 16 including a guide for
engaging said tab and carrying it against one of said belts thereby
rotatably orienting
18. A combination according to claim 17 wherein said slitter
includes a blade parallel to one of said belts and spaced from said
one belt a radius
19. Apparatus for jacketing a cylindrical body comprising means for
applying a jacket material to a major portion of an exterior
surface of said cylindrical body to leave a longitudinal tab of
said jacket material extending outward from said surface and a
longitudinally extending portion of said surface unjacketed so that
said cylindrical body can be slit longitudinally; and a slitter for
slitting said unjacketed portion of said cylindrical body
comprising a conveyor for advancing said cylindrical body
longitudinally; a guide for engaging said tab and rotatably
orienting said cylindrical body for the slitting of said
cylindrical body; and a slitting means oriented with respect to
said guide to slit said cylindrical body in
20. Apparatus for jacketing a cylindrical body comprising a fluid
applicator; advancing means for advancing jacket material past said
fluid applicator; means for sensing the position of said jacket
material along said advancing means and for selectively activating
said applicator in coordination with the advance of said jacket
material to produce a tacky surface on said material; conveying
means to convey said tacky surfaced jacket material and a
cylindrical body to a wrapping station for wrapping said jacket
material around said cylindrical body; means for positioning said
cylindrical body on said conveying means in front of said jacket
material and upstream from said wrapping station, said wrapping
station including means for retarding advance of said cylindrical
body with said conveying means and for rotating said cylindrical
body around its longitudinal axis while maintaining the body in
contact with said conveying means whereby said adhesive coated
jacket material is picked up by said cylindrical body as it is
carried by said conveying means and overtakes said cylindrical
body, said means for retarding and rotating said cylindrical body
being a flexible curtain overlying said conveying means and
engaging said cylindrical body on a side opposite that supported by
said conveying means.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
One product resulting from the practice of the method and operation
of the apparatus of this invention is the subject of U.S. Pat.
application Ser. No. 3,638 for "Self-Seal System for the
Installation of Insulation" by John Paul Mikulak which was filed
herewith.
BACKGROUND OF THE INVENTION
Heretofore jacketing has been applied to tubes of fibrous, thermal
insulation by manually coating a sheet of jacketing material with
adhesive and manually rolling the tube across the sheet so that the
tackey adhesive causes the jacketing to be picked up and bonded to
the tube. Hand operations of this nature are slow and involve high
labor costs. Adhesive is ordinarily applied with a manually
manipulated spray gun in a spray booth which obstructs the smooth
production flow of insulating tubes, jacketing sheets and jacketed
tubes. The supply lines and booths require substantial plant
area.
The present invention involves methods of and apparatus for
automatic or semiautomatic jacketing of tubular objects with a
resultant reduction in labor, enhancement of material flow in a
plant, increase in production speed and reduction in production
cost.
SUMMARY OF THE INVENTION
Sheet material cut to suitable length for encompassing cylindrical
bodies is removed from a stack and provided with a tackey surface
as it is advanced along a processing line. A cylindrical body is
positioned to intercept the sheet and engage the tackey surface so
that the sheet is picked up by the body. Apparatus is provided to
advance the sheet linearly from the stack to a station in which the
tackey surface is prepared and to confine the region which is
tackey to less than that required to encompass the entire outer
surface of the cylinder. A cylindrical body to be jacketed is
positioned with its longitudinal axis normal to the advance of the
sheet and is rotated counter to the direction of advance and across
the sheet.
While the process and apparatus are disclosed for utilization of
jacketing in sheets precoated with a dormant and non-tackey
adhesive which is activated by spraying an activator fluid on the
coating it can also be employed where the adhesive is sprayed on
jacketing which has not been precoated. Further, the automatic
formation of a restricted tackey zone on sheet jacketing can be
employed advantageously where insulating tubing is manually rolled
upon the sheet to apply it thereto. Automatic slitting of tubes
having a jacket tab and utilizing the tab as a means to index the
tube relative to the slitter blade can be practiced independently
of the remainder of the system as where tubes are jacketed
manually.
In one embodiment of the invention particularly applicable to pipe
insulation the jacketed tube has a region of jacketing which is not
adhered to the tube to expose a sector of the tube wall. This
sector is slit longitudinally to afford a means of slipping the
tube over a pipe. A tube with the jacketing adhered thereto is
advanced with its exposed sector in registry with a slitter blade
to automatically form the longitudinal slit. A flap or tab of
jacketing material having no tackey surface extends tangentially
from the tube adjacent the exposed sector. This flap is engaged by
indexing guides as the tube is advanced longitudinally so that the
tube is properly oriented with respect to the slitter blade.
A feature of the invention includes the means for forming the
tackey surface over a limited region of the jacketing sheet.
Another feature resides in the combination of a jacketing sheet
precoated with a dormant adhesive with a means to apply an
activator fluid to a restricted portion of the coating.
A third feature comprises means presenting the jacketing sheet at a
jacketing station in an orientation and direction of advance to
facilitate the application of the jacketing to the tube and the
wrapping of the jacketing around the tube.
A fourth feature involves mechanism for introducing tubes to the
jacketing station automatically.
A fifth feature is means for rotating the tubes counter to the
advance of the jacketing to automatically wrap the jacketing
thereon.
A sixth feature comprises means feeding tubes with jacketing
applied to a slitter.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow diagram of a method of applying jacketing
according to this invention;
FIG. 2 is a perspective of a preslit tube of pipe insulation with
the jacketing partially applied according to FIG. 1;
FIG. 3 is an end view of a pipe insulating tube jacketed and
processed according to this invention;
FIG. 4 is a side elevation of apparatus for automatically
activating selected areas of a precoated jacket and for conveying
the jacket into a jacketing station;
FIG. 5 is a side elevation partially in section of apparatus for
jacketing and slitting pipe insulating tubes automatically;
FIG. 6 is a schematic plan view on a reduced scale with portions
broken away of the apparatus of FIG. 5; and
FIG. 7 is a diagrammatic portrayal of an electrical and pneumatic
system for coordinating and controlling the combination of the
insulating tubes with jackets having zones of activated
adhesive.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
This invention involves wrapping a cylinder of generally circular
cross section with a sheet of jacketing which is adhered to a
portion or the entire outer face of the cylinder. In the
embodiments discussed the cylinder is of tubular form and of a
thermally insulating material to adapt it for pipe insulation
although it might be of other materials and for other purposes. The
jacketing is of a type suitable for vapor barriers for pipe
insulation although flexible sheet material of many forms might be
applied by the techniques and apparatus to be described.
The cylinder of the illustration is of a fibrous insulating
material which most commonly is formed of glass fibers produced by
passing glass filaments through small orifices in pots containing
molten glass. The filaments are subjected to hot gaseous blasts
which soften and attenuate them into small lengths of individual
fine fibers. The fibers are collected on a moving formation
conveyor and a binder, typically a thermosetting resin, is
introduced into the mat. The mat can be formed into cylinders by
being cut into lengths corresponding to the length of the total
number of convolutions to be employed in the cylinder and then
wrapped around and compressed upon a mandrel to form the cylinder
having the desired inner and outer diameter and density.
Alternatives to glass fibers formed as described can be employed
for thermally insulating tubes. These include other materials which
can be fiberized as by spinning, drawing, attenuating and blowing
into fine diameter fiber. Such material as silicates of metal
oxides, such as rock wools from argillaceous matter or shale, slag
wool from metallurgical slags, the commonly known "mineral wools,"
aluminum silicate fibers and any fibers of the so-called glasses
can be formed into suitable cylinders.
The jacketing is of flexible sheet material and can be of various
forms, depending upon its intended function. In the example of
thermal insulation jacketing a composite sheet of an outer layer of
paper, an intermediate reinforcing web of glass fibers, and an
inner layer of aluminum foil is employed. The jacketing is coated
on the metal foil inner face with an adhesive, advantageously of
the phenolic neoprene type having the characteristics that it is
inexpensive, can be applied in controlled quantities, is dormant or
not tackey, is flexible, is non-flammable and is readily activated.
A typical activator for the adhesive is a suitable solvent such as
trichloroethane or methyl chloroform.
In the combination of the composite sheet jacketing 11 applied to a
glass fiber mat tube 12 to provide a vapor barrier, the use of a
coating 13 of phenolic neoprene adhesive can serve to secure the
jacket to the tube or it can be employed for that purpose and as a
positive seal means for the insulation as installed by activating a
region of the coating of the adhesive on a tab or lap 14 which
remains deactivated during the factory application of the jacket.
In this latter instance the tube 12 is placed upon the pipe by
spreading the opposed edges of a longitudinal slit 15 to admit the
pipe to the tube interior. Manipulation of the opposed edges by
effectively providing a hinge region in the tube wall diametrically
opposed to the slit 15 is facilitated by a slit 16 which extends
partially through the tube wall from the interior of the tube. With
the hinge closed and the tube on a pipe, the tab 14 is made tackey
as by application of adhesive activator to the inner face of the
portion of jacket 11 left free of the tube 12 and by pressing the
tackey surface against the overlapped portion of the jacket to span
and close slit 15.
A number of methods are available for fabricating the jacketing 11
on a cylinder 12. When the selectively activated adhesive is
intended merely to adhere the jacketing 11 to cylinder 12, it has
been found that the adhesive can be applied as a coating of 3 grams
per square foot of jacketing. Where the more adverse field
conditions are to be met employing the adhesive costing to secure
the tab 14 in lapped relation and spanning slit 15, a coating of
the adhesive in a density of 6 grams per square foot has been found
advantageous to insure good sealing adhesion.
Jacketing sheets can be prepared from rolls of the material
precoated with the adhesive conditioned to a non-tackey state by
cutting sheets of jacketing 11 of a length exceeding the
circumferential length of the cross-section of the tube to be
jacketed by an amount providing an adequate sealing tab 14 and a
width substantially equal the longitudinal dimension of the tube.
Such sheets can be employed individually althoudh automated
jacketing is facilitated if they are collected in stacks 17.
Manual application of jackets 11 to tubes 12 can be accomplished by
appliying adhesive activator fluid to the portion of the coating of
dormant adhesive which it is desired to adhere to the tube, and
when the coating becomes tackey rolling the tube across the coating
to pick up the sheet. In practice, this can be accomplished by
placing the precoated sheet on a flat surface with its deactivated
adhesive coating upward and by applying the activator fluid to the
region to be adhered to the tube by masking or selective coating a
portion of the sheet 11. Coating can be by a spray gun, wiping rag,
sponge, brush or any other suitable means of applying a metered
amount of the activating solvent.
Advantageously, the tube 12 should be slit as at 15 and 16 prior to
jacketing manually. However, where automatic slitting as disclosed
below, is employed unslit tubes can be jacketed. A region of the
coating across the width of the sheet 11 and of a length extending
from an edge of the width dimension and less than the
circumferential length of the cross section of the tube to be
jacketed in length is activated on the sheet. Tube 15 is then
oriented on the edge of the sheet with its length parallel to the
width dimension so that an edge of slit 15 is adjacent the sheet
edge. The tube 12 is then rolled across the activated and tackey
adhesive as shown by the arrow A of FIG. 2 to pick up the sheet and
ultimately adhere all activated areas 13 to the tube 12 as shown in
FIG. 3 where tab 14 extends generally tangentially from the outer
face of the tube. Where the activated region is of a length
essentially three quarters of the circumference of the tube outer
face the tab 14 generally is tangential from a position in
quadrature with the first adhered end 18 of the jacket and is
parallel to the radial slit 15.
Simiautomatic applications of jacketing can be accomplished in the
apparatus of FIG. 4, where sheets of jacketing 11 positioned with
their deactivated coatings uppermost are individually removed from
a stack 17 and advanced linearly to an activating station 19 and
then across a dwell region 21 to a jacketing area 22. Stack 17 is
maintained in a tray 23 having sides and a bottom and mounted along
its rear edge on a hinge 24. An elevating hydraulic cylinder and
piston 25 is journaled at 26 on cabinet 27 and piston rod 28 is
journaled at 29 to the underside of tray 23 at its leading edge.
Means, such as a timer controlled pneumatic or hydraulic system
(not shown), periodically raises the leading edge of tray 23 by
admitting actuating fluid to cylinder 25 and then lowers the tray
to complete the cycle.
The uppermost sheet on stack 17 is removed during each cycle of
elevating and lowering tray 23 and is trasferred to a conveyor 31
comprising a plurality of upper and lower belts 32 and 33 trained
over grooved shafts 34 and 35 so they have parallel, adjacent runs
between which the sheet 11 is advanced to activating station 19. A
vacuum pickup 36 comprising an array of vacuum cups 37 on a
manifold 38 suspended on arms 39 radially extending from an
oscillatory shaft 41 journaled on frame 42 of conveyor 31. A
pneumatic line 43 extends from manifold 38 and can continuously or
periodically draw a vacuum on the manifold.
Pickup 36 operates in conjunction with elevator 25. Arms 39 are
rotated to a clockwise limit as shown in dashed lines in FIG. 4
while the tray 23 is in its initial lowered position and after the
tray has been elevated, vacuum is imposed on cups 37 to pickup the
uppermost sheet. Tray 23 is then lowered while the vacuum is
maintained and arms 39 are rotated to a counterclockwise limit as
shown in full in FIG. 4. In this position the leading edge of sheet
11 is introduced between the arrays of upper and lower conveyor
belts 32 and 33 and the vacuum is released to permit the sheet 11
to be drawn between the runs of belts 32 and 33.
Synchronization of the pickup operation with the elevation of the
tray 23 can be either by timing mechanism (not shown) programed
with the elevator or by limit switches (not shown) which sense the
travel of the stack to engage the pickup cups 37 for drawing the
vacuum and the retreat of the stack for actuating the oscillating
drive (not shown) for shaft 41. Conveyor belts 32 and 33 are
continuously run during operation of the apparatus so that shafts
34 rotate counter-clockwise and shafts 35 rotate clockwise at the
same speed and the adjacent runs of belts 32 and 33 advance from
the pickup 36 to the activating station 19.
One form of top sheet feeder drive is a pneumatic cylinder driving
(not shown) a crank to shaft 41 in a manner similar to the tube
release shaft to be described with respect to FIG. 7. A recycling
poppet valve 30 having its actuating plunger, oriented below tray
23 to be engaged by the return of the tray bottom to its lowered
position momentarily bleeds static air pressure from a first pilot
chamber of a bleeder type four-way valve (not shown) to shift the
pressurized air supply from one end of the crank drive cylinder to
the other. When the crank reaches its opposite limit it bleeds
static air pressure from a second pilot chamber of four-way valve
by releasing a poppet valve (not shown) to shift the pressurized
air back to the one end of the crank drive cylinder and return the
crank to its initial position. This return of the pilot valve is
permitted since the recycling poppet valve 30 is of a character to
be maintained closed following its opening on the stroke of its
plunger by the tray bottom even though its plunger is held
depressed and it can be reopened only be release and redepression
of the plunger on the next cycle of tray elevator.
As the sheet 11 emerges from conveyor 31 it is placed on conveyor
44 which can be a belt extending the width of the sheet and
slidingly driven over a table 45 by drive shaft 46 driven by motor
47. An array of spray heads 48 transverse of the conveying path are
mounted on a support rod 49 secured to frame 42 of conveyor 31.
Activator fluid is supplied to the heads 48 by flexible conduits 51
from manifold 52 which is coupled to a reservoir (not shown) which
can be maintained under pressure to force the activator from the
heads. The activator pattern from heads 48 coats a region of the
sheets 11 across their width as they emerge from between belts 32
and 33. Release of the activator from heads 48 is by means of
needle valves 53 which are supplied with and controlled by
pneumatic pressure through rod 49 from a solenoid operated valve 54
by means of tubing 55.
Valve 54 is controlled by an electrical circuit including limit
switches 56 and 57 having actuating arms 58 and 59 protruding
between belts 33 into the path along which sheet 11 is carried by
conveyor 31. The switch arms 58 and 59 are spaced apart the length
of travel equal to the length of the tab 14 to be formed in the
jacketing procedure and are arranged so that the solenoid valve 54
is open only in response to the coincidence of operation of both
switches by the engagement of their arms with a sheet 11. Where the
apparatus is to be employed on a range of jacket lengths, as for a
range of outer diameters of insulating tube, and the length of tab
to be formed varies, the limit switch sensing positions are made
adjustable along the length of conveyor 31. Further, the switch arm
59 of switch 57 is located according to the speed of conveyor 31
and the reaction time of applicator 19 so as to provide
preactivation distance which anticipates the travel of sheet 11 in
the delay interval between its signal and the initiation of the
cutting off of the spray of activator from heads 48.
As the leading edge of sheet 11 advances through the conveyor 31,
it engages and operates switch arm 58 with no effect at that time.
Further advance of sheet 11 engages arm 59 with its leading edge to
establish an actuating circuit for solenoid operated valve 54.
Continued advance of the leading edge of sheet 11 locates it
beneath heads 48 as the valve 54 is opened to cause needle valves
53 to open and initiate the spraying of activator fluid. As the
trailing edge of sheet 11 passes arm 58, the circuit for valve 54
causes it to close thereby initiating closure of needle valves 53
and the cut off of activator fluid. A region across the trailing
edge of the sheet 11 thereby receives no activator fluid and its
adhesive coating remains deactivated as indicated by the region 14
of sheet 11 in FIG. 2 having no stippling.
The sheet 11 with its leading portion coated with activated
adhesive advances on belt 44 through a reaction region 21 of
sufficient length to enable the activator to become effective and
render the adhesive coating to which it was applied tackey. It is
then carried to a jacketing region 22 where in the semiautomatic
jacketing process, an operator manually places a tube of pipe
insulation on the leading edge of the sheet 11 and rolls the tube
against the direction of advance of the sheet. Conveniently, the
operator is stationed at the end 61 of table 45 facing the
advancing jacketing sheets 11. He places the tubes 12 with the
margin of their slits 15, if pre-slit, on the leading edge of the
sheet 11 and their longitudinal axis normal to the direction
advance. The jacketing is completed by rolling the tube toward the
applicator 19 whereby the tackey face of the jacket is picked up,
initially as shown in FIG. 2 and finally as shown in FIG. 3.
The method of and apparatus for advancing individual jacketing
sheets 11 to a jacketing station can also be applied to processes
where adhesive is applied at applicator station 19. In this latter
instance, no precoating of adhesive is necessary. A hood is
desirable with suitable exhausting means (not shown) for the
applicator station 19 when the adhesive spray results in dangerous
or noxious vapors or particle suspensions in the adjacent
atmosphere.
A more completely automatic apparatus for jacketing and slitting
tubes of pipe insulation is shown in FIGS. 5 and 6. The unstacking
of sheets, their feed to an activator fluid application station,
the means of applying activator fluid or adhesive and limiting the
region over which the sheet coating is tackey, and the conveyor to
the jacketing station all correspond to the apparatus described
with respect to FIG. 4. Accordingly, the apparatus of FIG. 4 is
generally represented in FIG. 5 employing the same reference
characters as in FIG. 4.
In the apparatus of FIG. 5, tubes 12 are brought into engagement
with the jacketing after a delay such that the coating is afforded
an adequate interval following application of the activator to
become tackey (tack time) depending upon the adhesive, the
activator and the processing parameters such as temperature and
humidity. Tack time is adjusted by adjustement of the speed of
conveyors 44 and the travel distance for the activated coating from
application station 19 to jacketing station 22. The former is
adjusted by adjusting the speed of the drive either at motor 47 or
its drive coupling to shaft 46. Travel is adjusted by adjustment of
the position along the conveyor 44 of the equipement forming
jacketing station 22. This adjustment is by a carriage 62 traveling
on guides 63 along the conveyor table 45. The guides 63 can be
racks and the carriage can be mounted on pinions 64 suitably
journaled thereto and engaged with the racks.
The tube manipulating mechanism on carriage 62 comprises a tube
magazine 65 in the form of a hopper or bin having a bottom 66 which
can be moved, as by means of eccentric 67 and link 68 driven by
rotating motor 69, to agitate the supply of tubes 12 therein and
insure their feed through aperture 71 defined by adjustable gate
72. Gate 72 enables the apparatus to accommodate a range of tube
diameters, the height of aperture 71 being slightly in excess of a
diameter. A feed ramp 73 defined by spaced rods having upturned
ends 74 carries tubes from aperture 71 to a release position from
which they can be passed individually to the conveyor 44. A tube is
released by lifting it free of the ramp ends 74.
Tube release comprises spaced arms 75 interdigitating with the rods
of ramp 73 and journaled for rotation in bracket 76 extending from
carriage 62. Arms 75 are mounted on shaft 77 having a crank 78
driven by piston rod 79 and cylinder 81 pivoted at 82 to carriage
62. The piston and cylinder are supplied with a suitable drive
fluid under pressure (by means not shown) controlled (by means not
shown) to maintain arms 75 in the position shown whereby the return
of arms 75 from their previous tube feed cycle lifts the lead tube
on ramp 73 free of the ramp and the end of arms 70 holds the
following array of tubes short of the end 74 of ramp 73. The next
tube feed cycle lowers arms 75 to free the lead tube on ramp 73.
The next tube feed cycle lowers arms 75 to free the lead tube on
ramp 73 and permits it to roll to the ends 74 of the ramp. Each
return of arms 75 lifts the leading tube free of ramp 73 and
permits it to roll under influence of gravity along arms 75 to
stops 83 extending generally at right angles to the arms to form a
tube cradle at a radius around shaft 77 sufficiently beyond ends 74
of ramp 73 to permit the released tube to pass the ramp ends 74.
Each feed stroke of arms 75 is by valving controls which bleed
fluid from the upper end of cylinder 81 and apply fluid under
pressure to the lower end whereby piston rod 79 is extended to
rotate shaft 77 clockwise. This lowers arms 75 so that the tube
cradled between the arms and stops 83 rolls free and into inclined
guide rods 84. At the end of the clockwise stroke arms 75 are in
position B as shown in FIG. 5 and controls (not shown) such as a
poppet actuated by a cam on shaft 77 causes fluid to be bled from
the lower end of cylinder 81 and to be fed to the upper end until
arms 75 are returned to position shown in full.
Inclined guide rods 84 are mounted on cross bar 85 secured to
carriage 62. Depending from bar 85 are back stops 86 in the form of
vertical rods extending toward conveyor 44. Back stops 86 cooperate
with gates 87 to confine a tube 12 on the conveyor 44 to a region
of a length in the conveying direction slightly exceeding the tube
diameter. Where a range of tube sizes are to be jacketed in the
apparatus, the region between back stops 86 and gates 87 is
adjustable whereby it can be defined with appropriate dimensions
for the tube size being processed. Adjustment of the length of the
region is afforded by adjusting the position of support bar 85
along carriage 62 as by means of sliding guides and screw clamps
(not shown).
The insulating tube 12 is oriented on conveyor belt 44 with its
axis normal to the direction of advance of the belt and is
maintained at its initially deposited position by a pair of opposed
gates 87. As best seen, in FIG. 5, gates 87 are mounted to project
toward belt 44 adjacent each longitudinal edge of the belt from
overhead supports 88 which can be reciprocatable bars 89 guided for
reciprocation transversely of the conveying path from a position
maintaining opposed gates 87 in the path along which the tubes are
carried by the conveyor 44 to a position beyond the ends of tubes
on the conveyor.
Gates 87 can be biased by spring 91, as shown in FIG. 7, to their
closed position and can be opened by pressure fluid, conveniently
air, operating on piston 92 in cylinder 93 to displace piston rod
94 to the right. Linkage 95 pivoted at 96 and coupled to piston rod
94 provides the drive to open gates 87 by moving them outward.
Control of the gates is coordinated so that a tube is held at the
gates until a jacket is advanced to a position at which it is
essentially contacted with the tube. This can be accomplished by
sensing the approach of the jacket photoelectrically and actuating
the release of the gates as will be described with respect to FIG.
7.
A tube on the conveyor 44 is released just prior to the entry of
the leading edge of a jacket sheet into the region defined by stops
86 and gates 87. It is carried into the wrapping region by the
advance of conveyor 44 at the conveyor speed until it encounters
the drag curtain 97. Curtain 97 can be a relatively heavy sheet of
flexible material having sufficient friction with respect to tubes
12 so that the tubes are rolled between the drapped curtain and the
conveyor 44 and therefore advance in the conveying direction at
approximately half the speed of the conveyor. Conveniently, the
curtain 97 can be of metal links as a sheet chain suspended from a
head bar 98 secured to carriage 62 down stream of the gates 87.
With tube retarded and set in rotation by curtain 97, the closely
following jacket with its now tackey leading zone on its upper face
overtakes the tube 12 and advances beneath the rolling tube to be
picked-up thereby and carried around the tube until the entire
tackey zone of adhesive is adhered around the tube. The tube is
enclosed as shown in FIG. 3 at this point in its processing with a
flap 14 free of the cylindrical outer surface. Conveyor 44 carries
the jacket wrapped tube 12 to its end 98 and ejects it into a
suitable respository (not shown) or, as shown repository FIGS. 5
and 6 a conveyor 99 which carries it to a slitter.
When tubes are jacketed automatically, they can be fed from
magazine 65 in unslit condition and slit in their unjacketed wall
adjacent the jacket flap 14. Conveyor 99 comprises a pair of
endless belts 101 and 102 having the conveying surfaces of adjacent
runs essentially at right angles to each other along their lengths
and advancing at the same speed. These belts receive jacketed tubes
from an array of guide rods 103 at and below the end 98 of conveyor
44 so that the axis of the tube which was normal to the direction
of advance of conveyor 44 is parallel to the direction of advance
of conveyor 99. Guides which can be in the form of spring biased
fingers 104 pickup the flaps 14 of the jacketed tubes and rotate
them against the face of belt 102 whereby the tubes are rotatably
indexed for the blade 105 of the slitter position downstream of the
conveyor 99 from the guides. As in the case of the magazine gate 72
and the tube positioning zone, the slitter blade position is
adjustable to accommodate a range of tubes. The plane of slitter
blade 105 is spaced from the conveying run of belt 102 essentially
a radius of the tube 12. In addition the depth of cut of the blade
105 is adjustable to accommodate various wall thicknesses for the
tubes by adjusting its spacing toward and away from the conveying
run of belt 101. Slit and jacketed tubes are issued to a suitable
receptacle or additional conveyors (not shown) at the end of
conveyor 99.
FIG. 7 shows a control circuit for a system of the general form
shown in FIG. 5. In the embodiments of FIGS. 5, 6 and 7 the tube
gating operation is instituted by the approach of the leading edge
of a preconditioned jacket sheet 11 on conveyor 44 and the closure
of the gates 87 is instituted by the passage of the trailing edge
of a jacket sheet. The delivery of a tube to the conveyor follows
the closure of the gates 87 so that a tube is positioned on the
conveyor 44 immediately behind the trailing edge of a jacket sheet.
These operations are controlled photoelectrically by a unit 106
comprising a light source 107 directing light onto conveyor 44 and
a photocell 108 responsive to a change of light intensity from that
received from the surface of conveyor 44 to that received from a
sheet of jacketing 11 on the conveyor. Unit 106 is mounted
adjustably on carriage 62 as by mounting arm 109 so that it can be
moved with respect to the carriage parallel to the direction of
conveying and is aligned with and above the path along which jacket
sheets are conveyed with its light projected downward and its cell
responsive to light changes below it.
A power supply and signal responsive control 11 is coupled to unit
106 by suitable conductors and supplies an energizing signal to
solenoid 112 of valve 113 over conductors 114. Valve 113 controls
the position of piston 92 in cylinder 93 and thus the position of
gates 87 by passing air under pressure from supply 115 and conduit
116 to cylinder 93 when valve body 117 is retracted to provide
communication of air through passage 118. When valve body 117 is in
the extended position, exhaust passage 119 bleeds air from cylinder
93 to exhaust duct 121.
In operation, an advancing sheet of jacketing 11 is sensed by cell
108 to cause solenoid 112 to retract valve body 117 and thereby
extend piston 92 to open gates 87. When the trailing edge of sheet
11 passes from beneath cell 108 the valve body 117 is extended as
shown as by a biasing spring (not shown) to vent cylinder 93 and
enable spring 91 to retract piston rod 94 to close gates 87.
Delivery cylinder 76' has feed lines 122 and 123 at each end for
driving piston 124 and piston rod 79' pivotally coupled to crank
78' on feed actuating shaft 77' . Feed mechanism 125 comprises an
array of cams spaced along shaft 77' in non-interfering
relationship to feed ramp 73. Thus, the feed mechanism of FIG. 7
while somewhat similar to that of FIGS. 5 and 6 differs in that a
clockwise rotation of shaft 77' raises an insulation tube free of
ramp end 74 and permits it to drop on drop guide rods 84.
Piston 124 is displaced pneumatically by air from supply 115 passed
to cylinder 126 of a four-way air operated valve 127 through
conduit 128. A barrel 129 of value 128 in the form of opposed cups
131 and 132 forming pistons of a pilot valve coupled by bridge 133
is shiftable axially of cylinder 126 to transfer slide block 134
between one of ports 135 and 136 and exhaust port 137. Slide block
134 has a smooth sealing fit with face 139 and contains a cavity
141 which spans the port 137 and one set of the ports 135 and 136.
It is maintained in sealing relationship to face 139 by bias spring
142. In the position shown, valve 127 vents line 123 to atmosphere
and applied pressurized air from supply 115 to line 122 through the
cavity around the central portion of barrel 129 thereby tending to
shift piston 124 from the upper end of its stroke to a lower
position in cylinder 76' .
Valve 127 is shifted by bleeding pressure from lines 143 or 144 to
atmoshpere. This enables the high pressure in the main cavity to be
effective on the ends 145 or 146 of cups 131 and 132 respectively
to displace the barrel 129. This force is developed by the pressure
unbalance and effective areas upon which the pressure is imposed. A
restricted flow of high pressure air is admitted to the interior of
each cup 131 and 132 through passages 147 and 148 so that in the
static condition, the pressures on the inner and outer faces of the
two opposed cups are balanced. When pressure is bled from line 143,
the force on face 145 exceeds that of the pressure in the interior
of cup 131 and barrel 129 is shifted to the left. This shifts slide
134 to the left to expose port 135 to the high pressure of the
valve interior and connects port 136 to exhaust port 137 via cavity
141. A seal 149 at the bottom of cup 131 closes the port to 143 and
the bleed hole 147 permits high pressure air to enter the cup and
build up the pressure in its interior.
Bleeding of line 144 to atmosphere reduces the pressure in cup 132
to produce an unbalanced force from the high pressure on face 146.
This shifts barrel 129 to the right, transferring slide 134 to vent
port 135 and expose duct 136 to high pressure from the interior
127. Piston 124 is thereby driven upward in cylinder 76' . Each
time a pilot port 143 or 144 is bled to atmosphere while the barrel
is at a position spacing the cup 131 or 132 associated with that
port from its seated condition the barrel will be shifted toward
the port and will cause a corresponding shift of the control valve
slide 134.
Valve 127 is controlled by the bleeding functions of poppet valve
151 having the characteristic that it bleeds air from line 144
while its spring biased plunger 152 is depressed and by recycling
poppet valve 153. Valve 153 bleeds line 143 during the depressing
travel of plunger 154 at a critical point in that travel and until
pressure in the line has been reduced and thereafter reseats to
closes line 143, even though the plunger 154 is maintained
displaced until the plunger has been extended and again depressed.
Valve 153 is shown in its closed condition with plunger 154
depressed. Valve 153 includes a stem 155 having a hollow bore 156
closed at its end 157 and a flange 158 against which a spring 159
is biased. An aperture 161 from cavity 162 into bore 156 provides
connumication to inner cavity 163 when stem 155 is displaced to
expose aperture 161 to cavity 162. Inner cavity 163 is coupled to
exhaust ports 164 when stem 155 is displaced. A toggel stem 165 is
mounted in sleeve 166 and is actuated by cam 167 on plunger 154. It
is shown coaxial with and telescoped within bore 156 as in the
seated condition with its plunger depressed. Toggel stem 165 is
biased by spring 168 and when recycled is cocked relative to the
longitudinal axis of the valve and the direction of travel of
plunger 154. Depressing plunger 154 initially causes stem 165 to
bear upon and depress stem 155 to a valve opening condition.
Thereafter, its camming face 169 causes it to longitudinally align
itself with the valve axis. Thus, it initially exposes port 161 and
exhaust ports 164 to bleed line 143. With stem 165 axially aligned
with bore 156 to enter that bore stem 155 is biased closed by
spring 159. Thus plunger 154 can remain depressed and plunger 155
will reclose the valve.
In the present control the feed of tubes 12 is actuated by the
closing of gates 87 following the passing of photoelectric unit 106
by a jacket sheet 11. Spring return of piston rod 94 to the
position shown causes link 95 to rotate shaft 96 in a
counter-clockwise direction thereby carrying cam 171 on shaft 96 to
a position depressing plunger 154 and opening recycled valve 153
momentarily. With line 143 bled to atmosphere, barrel 129 moves to
the left, as shown to admit high pressure air to the line 122 and
the upper end of cylinder 76' while line 123 is vented to the
atmosphere. Piston 124 is driven downward rotating shaft 77'
clockwise so that cam surfaces 125 lift the first tube 12 free of
ramp end 74 while retaining the next tube to permit return of cam
125. When crank 78' or a corresponding cam on shaft 77' engages and
depresses plunger 152, line 144 and the pilot valve cup 132 are
bled to atmosphere causing barrel 129 to move to the right. This
shifts slide 134 to apply high pressure to line 123 and the lower
end of cylinder 76' while it bleeds the upper end of cylinder 76'
through line 122 to atmosphere. Piston 124 is immediately driven
upward to rotate shaft 77' counter-clockwise to its limit and
another tube 12 is permitted to roll to the end 74 of ramp 73. In
this condition the recycling valve 153 remains closed with its
plunger 154 depressed, the four-way control valve 127 has barrel
129 and slide 134 displaced to the right, poppet valve 151 is
closed and piston 124 is at its upper limit of travel so that the
system is prepared for another cycle when the gates 87 are again
opened to reset valve 153 and then are reclosed.
It is to be appreciated that the methods and apparatus of this
invention can be employed as a system or as individual
subcombinations for the several steps of fabricating a jacketed and
slit tube of pipe insulation. Thus the method of precoating a
jacketing with a dormant but activatable adhesive and utilizing
that adhesive by application of an activator fluid could be
employed without automatic apparatus to produce a tackey surface
upon which a tube is rolled to pickup the jacket sheet. The
apparatus for producing the localized tackey region can apply an
adhesive as where the jacketing sheets have not been precoated.
That apparatus has been used with conveyor 44 with attendants
manually positioning and rolling tubes 12 on the tackey jacketing
sheet. The automatic tube positioner and rolling mechanism could be
preceded by a manual application of the tackey jacket surfacing and
could be followed by a manual slitting operation.
Further, the various details of the apparatus lend themselves to
modification, alternatuves, and variations. For example, the
pneumatic drives might be hydraulic or electromagnetic drives. The
work piece manipulating elements and combinations can be varied as
in the illustrated tube release variations of FIGS. 5 and 7.
Accordingly, it is to be understood that the above disclosure is to
be read as illustrative of the present invention and not in a
limiting sense.
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