US3796388A

US3796388A - Apparatus for winding a running length of thermoplastic sheeting into a series of rolls

Info

Publication number: US3796388A
Application number: US00057678A
Authority: US
Inventors: D Davis
Original assignee: EI Du Pont de Nemours and Co
Current assignee: EIDP Inc
Priority date: 1970-07-23
Filing date: 1970-07-23
Publication date: 1974-03-12
Anticipated expiration: 1991-03-12
Also published as: DE2136726A1; BE770318A; CA957353A; FR2109670A5; GB1336786A

Abstract

A system and method for automatic handling a running length of thermoplastic sheeting to form a series of individual rolls wherein the method comprises collecting the running length of sheeting, moving a core containing a certain length of sheeting away from the general path of movement of the sheeting, moving an empty core into the general path of movement of the sheeting, severing the sheeting and heat bonding the end of the running length of sheeting to the empty core and winding the running length of sheeting on the empty core; and wherein the system comprises basically an accumulator unit, sheet forwarding means, windup promotion means, windup unit, and severing unit all cooperating through a control means to accomplish the primary objective. Rolls of sheeting made from the system and method.

Description

United States Patent [191 Davis [4 1 Mar. 12, 1974 [75] Inventor: Douglas Steward Davis,

ParkersFurg, W. Va.

[73] Assignee: E. I. du Pont de Nemours and Company, Wilmington, Del.

22 Filed: July 23,1970

21 App1.No.:57,678

[52] US. Cl. 242/56 A, 206/59 C, 242/64 [51] Int. Cl B65h 19/26, B65h 19/28 [58] Field of Search 242/56 A, 56 R, 64, 74,

2,860,839 11/1958 Bower 242/56 A Primqry xaminer- -George F. Mautz 5 7] ABSTRACT A system and method for automatic handling a running length of thermoplastic sheeting to form a series of individual rolls wherein the method comprises collecting the running length of sheeting, moving a core containing a certain length of sheeting away from the general path of movement of the sheeting, moving an empty core into the general path of movement of the sheeting, severing the sheeting and heat bonding the end of the running length of sheeting to the empty core and winding the running length of sheeting on the empty core; and wherein the system comprises basically an accumulator unit, sheetforwarding means, windup promotion means, windup unit, and severing unit all cooperating through a control means to accomplish the primary objective. Rolls of sheeting made from the system and method.

1 Claim, 7 Drawing Figures PATENIEI] IIAR 1 2 I974 SHEEI 1 0F 5 FIG-1 AGENT FIG-3 INVENTOR DOUGLAS STEWARD DAVIS AGENT PATENTEB III! I 2 B74 SHEET [IF 5 FIG-6a INVENTOR PS-l DOUGLAS STEWARD DAVIS AGENT PATENTEBMR 12 1914 3.796388 sum 5 or 5 F l G 6 b E PS-7 INVENTOR DOU GLAS STEWAR D DAVIS BY M L M AGENT APPARATUS FOR WINDING A RUNNING LENGTH OF THERMOPLASTIC SHEETING INTO A SERIES OF ROLLS BACKGROUND OF THE INVENTION This invention relates to a system and method for automatically winding into a number of rolls a running length of thermoplastic sheeting. Particularly, this invention relates to a system for automatically moving a full roll of sheeting out of the winding position, heat bonding the severed end running length of sheeting to an empty core and moving the empty core into position for winding. More particularly, this invention relates to a roll of sheeting made utilizing the automatic system which comprises the core and a plurality of layers of sheeting adjacent thereto with the end of the first adjacent layer of sheeting being heat bonded to the core.

It is known that sheeting can be attached to cores l) by wrapping the sheeting around the core such that the end of the sheeting which is adjacent to the core is caught under the next layer of sheeting and therefore thevsheeting is held fast to the core and (2) by gluing the end of the sheeting to the core. It is also known that thin sheeting up to about 0.75 mil can be cut with a hot wire cutter and mechanically started on an empty core (U.S.Pat. No. 3,091 ,41 l Turret type winders are also known.

The known methods of attaching sheeting to a core were found to be inadequate in that the gluing was not flexible in that it could not be used with sheeting which was covered with powder, etc. and the catch-type methods of securing the sheeting on a core frequently involved a fold-back forming at the point where the end of the sheeting which is adjacent to the core is overlapped by the second layer of sheeting. This fold-back caused a great deal of waste, i.e., about -15 layers of sheeting since the sheeting would be unduly stressed at the point of overlap of the fold-back. Further, even when there was no fold-back, a sharply cut end of sheeting would cause stresses in a number of adjacent layers such that they had to be discarded.

A system, method and resultant roll were sought which would (1) allow one to cut a running length of sheeting and secure the sheeting on an empty core without stopping the continuous flow of sheeting through a processing unit, (2) avoid the waste from fold-back and from the sharp edge on the end of the sheeting, and (3) allow for automatic changing from a full to an empty core.

SUMMARY OF THE INVENTION A system has been found which fulfills the above requirements. It is a system for automatic handling of a running length of thermoplastic sheeting from a processing unit to form a series of individual rolls'which comprises in combination an accumulator unit cooperating with the processing unit and positioned along the general path of movement of the sheeting; sheet forwarding means cooperating with the accumulator and positioned along the general path of movement of the sheeting; windup promotion means cooperating with the sheet forwarding means and positioned along the general path of movement of the sheeting; a windup unit cooperating with the windup promotion means and positioned along the general path of movement of the sheeting, said windup unit comprising means for moving a core containing a certain length of sheeting away from the general path of movement of the sheeting and replacing said core containing a certain length of sheeting with an empty core; and a severing unit cooperating with the windup unit and positioned along the general path of movement of the sheeting, said severing unit comprising means for severing the sheeting and heat bonding the end of the running length of sheeting to the empty core; saidI accumulator unit, sheet forwarding means, windup promotion means, windup unit, and severing unit cooperating through a control means to cause the accumulator unit to collect the sheeting from the processing unit which continues to operate while the core containing a certain length of sheeting is automatically moved from the general path of movement of the sheeting, the sheeting severed, the end of the running length of sheeting heat bonded to the empty core and the empty core moved into the general path of movement of the sheeting.

Also included in the invention is a method for utilizing the system and a roll of sheeting made therefrom. The method is a method for automatically changing from a core containing a certain length of thermoplastic sheeting to an empty core when winding a running length of sheeting into a series of rolls which comprises (a) collecting the running length of sheeting, (b) moving the core containing a certain length of sheeting away from the general path of movement of the sheeting, (c) moving the empty core towards the general path of movement of the sheeting, (d) severing the sheeting and heat bonding the end of the running length of sheeting to the empty core, and (e) winding the running length of sheeting on the empty core. The roll of sheeting is described later.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial over-all side view with some parts in section of the windup unit and severing unit showing (1) their relation to the accumulator unit, windup promotion means, etc. and (2) the various positions of the windup unit and severing unit during the automatic roll change.

FIG. 2 is a partial view of the windup unit and severing unit with some parts shown as cut-a-ways viewed from the general path of movement side of the windup unit.

FIG. 3 is a partial cross section of the severing end of the severing unit and core in position for severing the sheeting and heat bonding.

FIG. 4 is a partial cross section of the severing end of the severing unit and core in position during cooling after severing and heat bonding.

FIG. 5 is a partial cross section of the core containing layers of sheeting showing the bond of the end of the first adjacent layer of sheeting to the core.

FIGS. 6a and 6b are partial schematics and diagrammatics of the fluid pressure control, operating systems and cooperating machine components of a preferred apparatus embodying the principles of the invention.

DESCRIPTION OF PREFERRED EMBODIMENTS A partial over'all side view of the system is shown in FIG. 1 with parts in section. Unit I is the accumulator unit which receives the sheeting from the processing unit (not shown). The accumulator unit is utilized to collect the sheeting flowing from the processing unit and allow it to operate while the windup unit 3 and severing unit 4 are accomplishing the core change during which time the flow of sheeting to the windup unit is for the most part nonexistent.

Unit 2 which is in the general path of movement of the sheeting between the accumulator unit 1 and the windup unit 3 can be a number of or combinations of items including sheeting forwarding means, i.e., drive rolls; a slitter to trim the edge of the sheeting; and a series of rolls to produce the correct amount of tension in the sheeting and thereby promote windup.

Unit 5 is a rider roll which is useful in promotion of windup. It lifts so as to be out of the general path of movement of the sheeting during the core change operation and does not go down to normal operating position until the empty core is in normal winding position. The rider roll consists of the roll 6 and means for holding it and moving its position 7. The rider roll smooths the sheeting as it is placed on the roll and assists in providing the proper tension in the sheetingfor winding in the windup unit.

Unit 3 is the windup unit and comprises a rotating turret 8 moved by motor 9 and drive means 10, supported by and rotating with shaft 11 which is supported by bracket 12, supported by supporting

frames

13 and 14. The rotating turret 8 comprises two spindles 15 and 16'which contain air operated

chucks

17 and 18 for holding the cores l9 and 20, 20 contains a certain predetermined length of sheeting and drive (21,22) means for rotating the chucks l8 and 19 which are driven by

motors

23 and 24 held in position by

motor mounts

25 and 26 on shaft 11. The air operated chucks are operated by

air lines

27, 28, 29 and 30, each air line being represented by a single line.

FIG. 1 indicates the 4 positions of the empty core or core containing a certain length of sheeting (full roll) during normal operation and during the severing and heat bonding of the sheeting. Position 1 is where the full roll is when the core is in normal winding position (position 3). The full roll at position 1 is dropped off at that point and replaced by an empty core ready to replace the core which is being filled in position 3. The sequence of oeprations which occurs in the windup unit during a core change is discussed below and uses as its beginning point in the sequence as the point where the core is being filled as in position 3 and the previously filled full roll which was in position 1 has been replaced by an empty core.

When it is indicated that the core in position 3 contains a certain length of sheeting, the turret 8 rotates the core from position 3, 270, to position 2, thereby, placing the empty core in position 4. The running length of sheeting after the 270 rotation is shown by line 31 which indicates that it overlaps the core 19 (empty) in position 4 and is still continuous with the sheeting on the core containing the certain length of sheeting in position 2. After severing and heat bonding in whichthe severed end of the sheeting attached to the core containing the certain length of sheeting drops and the severed end of the running length of sheeting is heat bonded to the core, the turret 8 rotates 90 such that the empty core with the running length of sheeting heat bonded to it is in position 3 and the roll containing the certain(predetermined) length of sheeting is in position 1 where it is to be replaced by an empty core.

Unit 4 is the severing unit which severs and heat bonds the sheeting to the empty core. Supporting frame 32 and beam 33 support eyes 34 which in turn support shaft 35 which holds and allows arm 36 to move via air cylinder 37 which is operated by air lines 38. The air cylinder 37 is supported by beam 33 and bracket 39 and is connected to arm 36 by connecting means 40. Arm 36 holds among other things the severing member (wire) 41 and clamp 42 which is operated by air cylinders 53 fed by air lines 44 which are in turn fed by air supply 45. The clamp 42 and severing member 41 are enclosed by

rubber aprons

46 and 47.

Air supply 45 also feeds via lines 48 air jets which are not shown in FIG. 1. The rest of the description of the severing end of the severing unit is reserved for more detailed FIGS. 2, 3, and 4.

FIG. 1 indicates the two positions of the severing end of unit 4, i.e., the severing unit which are position A which is the position during normal winding and position. B which is the position during severing and heat bonding. In position B, the severing end of the severing unit is in operative association with the sheeting and empty core. The heating means for the severing member 41 is not shown in any of the Figures and is a means for carrying current to severing member 41.

The severing end of the severing unit 4 is in position B part of the time when the core (empty) is in position 4 and the core containing a certain length of sheeting is in position 2. When the turret 8 is rotating or in position so the cores are in

positions

3 and 1, the severing unit 4 is in position A. FIGS. 3 and 4 give detailed depiction of the severing end of the severing unit while in position B.

FIG. 2 is a partial view of the windup unit 3 and severing unit 4 looked at from the path of movement of the sheeting. The turret 8 is in position such that

spindles

15, 15', 16 and 16 containing air chucks 17, 17, 18 and 18' fed by

air lines

27, 28, 29, 30, 27, 28, 29 and 30 are situated with

spindles

15 and 15 in position which corresponds to position 4 of FIG. 1 and 16 and 16' in position which corresponds to position 2 of FIG. 1. The air chucks 17 and 17 are rotated by drive means 21, powered by motor 23 which is supported by motor mount 25. Motor 24 powers drive means 22 which rotates air chucks 18 and 18. The turret 8 is supported by and rotates with shaft 11, which rotates in bearing means 49 and 50, is supported by

brackets

12 and 12 held by supporting

frames

13, 13, 14 and 14', and is rotated by drive means 10 powered by motor 9.

Supporting frames 13, 14, 13 and 14' also support the severing unit 4 through

support frame

32 and 32 and beam 33 which holds eyes 34 and 34' which support and allow shaft 35 to rotate. Shaft 35 supports the arm 36 of the severing unit 4. The arm 36 holds air cylinders 43, clamp 42, air jet 51, air line 44 to the air cylinders 43, air lines 48 to air jets 51, holding means for the severing member 52, severing member 41 and

rubber aprons

46 and 47. The air lines are supplied by air supply 45. The arm 36 is moved to and from the severing and heat bonding position by connecting means 40 driven by air cylinder 37 supported by bracket 39.

The air cylinders 43 are attached via their plunger 53 to the clamp 42 and move the clamp into operative association with the sheeting and empty core during the severing and heat bonding of the sheeting to the core. The clamp 42 extends the length of the severing member 41. The clamp 42 and air jets 51 are shown in detail in FIGS. 3 and 4.

FIG. 3 is a cross section of severing end of the severing unit indicating its position at the point of severing and heat bonding. The rubber aprons 46 and 47 enclose the clamp 42 which consists of a rubber layer 54 backed by a metal layer 55 and is attached to a plunger 53 from an air cylinder 43 which moves the clamp 42 in operative association with the sheeting 31 and core 19. The clamp 42 holds the sheeting 31 in place during the severing and heat bonding.

The rubber aprons 46 and 47 also enclose the holding means 52 for the severing member 41, i.e., severing wire. The holding means 52 is supported by support frame 56 while the air cylinder is supported by support frame 57. The clamp 42 operated by the air cylinder 43 and its plunger 53 along with the support frame 56 and holding means 52 keep the severing member 41 in operative association with the sheeting and core, i.e., in contact with the sheeting core and sheeting during the severing and heat bonding of the sheeting. The heating means for the severing member is electrical and is not shown.

FIG. 3 is the position of the severing end of the severing unit from the time the severing end of the severing unit is initially lowered to the sheeting and core until it is raised a small amount with the clamp holding its position for cooling. This position is shown in FIG. 4.

FIG. 4 depicts the aforesaid portion of the severing end of the severing unit. Once again the

rubber aprons

46 and 47 enclose the clamp 42 consisting of the rubber layer 54 and metal backing layer 55 attached to the plunger 53 of the air cylinder which is not shown. In this position, however, the severing and heating bonding have taken place and the severing end of the severing unit has been lifted a small amount, about an inch with the plunger 53 of the air cylinder extending so as to continue to hold the running length of sheeting 31 to the core by holding at a point near the end of the running length of sheeting 31 into the core 19 so that the end 31 of the running length of sheeting which has just been heat bonded to the core via the severing member 41, the severing member being held by the holding means 52 which is supported by support frame 56, can have sufficient time to form a solid bond with the core. The formation of the solid bond is promoted by cooling from air which is provided by air jets 51 supported by support frame 57 with the flow of air shown as 58. The flow of air continues on the heat bond and the severing end of the severing unit stays in the position depicted in FIG. 4 until it is indicated that the accumulator unit is'sufficiently full, i.e., about 75 percent full and then the cooling stops and the clamp 42 lifts while the entire severing end of the severing unit is moved away from the core 19. The recently severed end of the sheeting 31" which is attached to the core containing a certain length of sheeting (not shown) drops away from the core 19 as soon as the severing is complete which is prior to the cooling via the air jets 51. A detailed description of the sequence of events is described later in the discussion of schematics 6a and 6b.

FIG. 5 is a partial cross section of a core 20, the first adjacent layer of thermoplastic sheeting 31 which has the tapered end 31 heat bonded to the core. The tapered edge causes less stress at the point on the layers of sheeting 32" where they overlap the heat bonded, tapered end of the sheeting.

The entire roll of thermoplastic sheeting of which FIG. 5 is a partial cross section comprises (a) a core 20, (b) a first layer of sheeting immediately adjacent thereto 31, said first layer being heat bonded to said core by a heatbond 31' between at least a portion of the end of said first adjacent layer 31 and said core and (c) a plurality of layers 31' of sheeting continuous with and adjacent to said first layer. The bond between the first layer and core is tapered to an extent that less than about 6 of the adjacent layers of sheeting overlapping said bond are stressed to such an extent at the point of overlap that there is a visible optical distortion relative to the remainder of the sheeting. The tapering of the bond is normally accomplished by utilizing a severing member which has a solid cylindrical cross section although members with other cross sections can be utilized. Many sizes and shapes of severing members are useful but a particularly useful wire for 15 mil to 40 mil sheeting is about 0.1 inch diameter wire.

The composition of the core can vary and is not cirtical. A preferred core is one which is annular and contains an inner and outer cardboard layer with a layer of aluminum between them. The length of the core is not critical but normally runs from about 20 to about 45 inches with the preferred being about 30 inches. The diameter of the core is also not cirtical but normally varies from about 3 to about 8 inches outside diameter.

The sheeting in the roll of sheeting is thermoplastic and can be many various types of sheeting. The preferred types are polyvinyl butyral, plasticized polyvinyl chloride, polyurethane, ethylene/vinyl acetate copolymers and hydrolyzed ethylene/vinyl acetate copolymers. The sheeting may be coated with powder such as sodium bicarbonate, potassium bicarbonate, etc. if the properties of the sheeting are such that it is necessary to allow the sheeting to be conveniently handled.

FIGS. 6a and 6b are a partial schematic of the control system, i.e., control means which causes each of the parts of the system described above to operate automatically in a sequential manner to form the above described rolls of sheeting. FIGS. 6a and 6b show the position of the valves when the system is running at normal winding and is ready to begin an automatic roll change. This is evident by the diagrammatic representation of the rider roll 6 and its holding means 7 indicating that it is down in the normal winding position on top of the core being wound 20, held by spindle 16 which is in the normal winding position, position 3 of FlG. 1.

Throughout the discussion of the schematic the following will always hold: (1) if there is an S leading into the switch, valve, etc., this means that they are constantly supplied with air from a main air manifold, (2) thew. indication on a valve, switch, etc. indicates that it has a spring return and will return to the position opposite to the spring when the force causing it to move towards the spring is removed, (3) E means that the valve, switch, etc. is supplied constantly with electricity from a main supply line, (4) when the arrow in the switch, valve, etc. is directed towards a wall with no outlet, this means the valve is plugged in that position, and (5) the arrow in an air relay stays at the last position to which it is moved until it is moved by another surge of air.

If the cycle is entered at the point where the operator has just removed the full roll (core containing a certain (predetermined) length of sheeting) and replaced. it with an empty core, this being the only manual operation if the system is running on its automatic sequence; it is found that the first step in the cycle is the operator pushing spring-return air switch D1. The pushing of D1 sends a surge of air pressure to R1, and air relay, which causes the arrow in R1 to shift so that air is flowing through R1 to P1, this will continue until the arrow of R1 is shifted back by air from spring-return air valve Tl which is actuated by a cam sequencer via Tls cam follower on the left side of valve T1. T1 is supplied with air from air relay R which always has its arrow up during the normal automatic cycle. The shifting of the arrows of R1 by T1 occurs shortly after the empty core 19 held by spindle reaches the cutting position indicated diagrammatically in FIG. 6b.

Therefore, in the cycle at this point air is flowing through R1 to P1, a spring-return air valve, causing the arrow of P1 to shift so that air can flow through. No air flows until the footage counter via the electrical signal at (3-1 shifts the spring-loaded solenoid valve SV-l so that air is flowing through it. It does this when the footage counter counting the length of sheeting winding on to the core indicates that a certain predetermined amount of sheeting has been wound on the core. The air flowing through SV-l flows via .L to the accumulator to start it collecting the sheeting, via L to the sheet forwarding means between the accumulator and windup unit to stop its operation, and up to shuttle valve V1 which allows flow to the right but not to the left when there is air pressure from SV-l.

Since P1 has its arrow moved so that it is opened, the air flows through it to spring-return air valve P2 which has its arrow such that it allows the air to flow through to air relay R2. The arrow in P2 is down since it is pushed down by air from spring-return air valve T2 which is supplied by air relay R3. T2 has its arrow in position to allow air to flow through when the end of a cycle has been reached and it is ready for another cycle to begin. R3 has its arrow to the left at all times except when a repeat cut is required. T2 is actuated by a cam sequencer which has 2 lobes on it for T2 so that the arrow in T2 is to the right at the beginning of the cam sequencer cycle and when the cooling cycle is taking place.

The air from P2 then has reached R2 causing R2s arrow to go down and allow air to flow through it. The arrow stays down until lifted by T1 which occurs at the same time that R1 is shifted as was described above. The air flowing through R2 flows to spring-loaded solenoid valve SV-2 and to air relay R4. Nothing happens to SV-2 at this point because its arrow has not been shifted by the empty core reaching the cutting position. R4, however, has its arrow shifted to the bottom position via air flowing from R2 through V2 and air flows into cylinder 59 causing piston 60 to lift the rider roll 6, all of which are shown diagrammatically.

When the rider roll 6 reaches the position for the core change, the piston 60 comes in contact with the ball follower of spring-return air valve T3 shown as the projection on the right side of air valve T3. This causes the arrow in T3 to shift to the left and for the air which is flowing through spring-return air valve T4 which has its arrow to the right since its ball follower is in contact with the piston 61 in cylinder 37 of the severing unit, both of which are shown diagrammatically. The air to T4 is supplied through air relay R5 which has its arrow pointed up at all times while the system is in normal automatic mode.

T3 has air flowing through it since the rider roll is up. The rider roll has stopped since the piston 60 has come against a mechanical stop, the top of the cylinder 59 and is being held there by the preseure of the system.

The air through T3 flows to pressure-operated electrical switch PS-l which has electrical current to it from (1-1 which indicates the core contains a certain length of sheeting. The pressure from T3 which indicates the rider roll is up (out of the general path of movement) causes the needle in PS-l to shift to the bottom position which gives electrical current flow through PS-l. This causes an electrical signal H-l to cause the turret to rotate 270 in the direction such that the core containing a certain length of sheeting is moved away from the general path of movement of the sheeting while the empty core rotates 270 to a position under the severing unit. The electrical signal H-l also causes the roll containing a certain length of sheeting to wind backwards paying out slack while it is moving from the general path of movement of the sheeting, the payed out sheeting overlaps the empty core when the movement is complete.

T3 also sends pressure to a spring-return air valve T5 which is cam operated. Since it is not operated until later in the cycle, air does not flow through T5.

When the core containing a certain lengthof sheeting reaches electrical limit switch LS-l at the end of the 270 rotation of the turret, it shifts the needle in LS-l so that current flows through LS-l to electrical relay J1 which causes its needle to move up and allow current to flow through J1. (J1 is reset to the bottom off position by the electrical system through EE when the empty core after severing and heat bonding begins to move to the winding position). The current through J1 gives a current source to electrical limit switch LS-2 which causes the motors to stop the rotation of the turret via I-l-2 when the spindle containing the empty core contacts the contact follower of LS-2 which indicates it is under the severing unit. Electrical current also flows through LS-2 to electrical limit switch LS-3 which causes current to flow through if one spindle is at the severing unit, and the contact follower is not contacted, this beingindicated to the electrical system via H-3. If the contact follower of LS-3 has contact, the needle moves to the right and indicates to the electrical system through H-4 via a flow of current that the other spindle is at the severing unit. This is necessary so that the electrical system will cause the correct core to rotate when winding is called for.

The current from LS-2 also causes switch SW to close indicating that all motors are off. This causes the arrow in SV-2 to be moved down and since SV-2 has an air supply from R2, air is supplied to spring-return air valve T6 which allows the air to flow to springreturn air valve T7. The air stops at T7 until its arrow is shifted by the cam sequencer.

Air also flows from SV-2 to air shuttle V3 and on to spring-return air valve T8 and air relay R6. The air flowing to T8 causes its arrow to be shifted to the left which vents the left side of R6 via line II. The air flowing from SV-2 to R6 causes its arrow to be shifted from brake 12 which is the brake on the cam sequencer to the left which causes the air to flow to air relay R7 which has its arrow to the left causing the cam sequencer to run at normal speed via line l3.

The first function of the cam sequencer is to contact the cam follower on spring-return air valve T9 which is supplied by R3, R3 having its arrow to the left. T9s arrow is shifted to the right and air flows through air shuttles V4 and V5, through spring-return air valve T10 to pressure-operated electrical switch PS-2. This causes the needle in the switch to come down and electrical current to flow via H- to the electrical system which causes the correct spindle motor via H-3 and H-4 to rotate the empty core so as to clean the powder off the sheeting which is overlapping the empty core as a result of the 270 rotation of it and the core containing a certain amount of sheeting via the turret. This particular embodiment is concerned with winding sheeting covered with powder. The spring on T9 causes the arrow to move back to the left after the lobe on the cam passes and then the rotation of the core ceases.

After the core is rotated to clean off the powder on the sheeting, the cam sequencer actuates spring-return air valve T7 causing its arrow to shift left. This sends air through air shuttle V6 to air relay R8 causing the arrow in R8 to be shifted up causing air to flow into cylinder 37, pushing piston 61 down causing the severing unit to move down towards the core. When the severing end of the severing unit gets down to its proper position in operative association with the empty core and the sheeting which is overlapping it, its piston actuates the ball follower on spring-return air valve T11 which has its arrow shifted right causing air to flow first to air relays R9 and R10. This causes the arrow in R9 to shift up but no air is being supplied to R9 at this point so nothing flows through .it. in R10, the air from T11 causes the arrow to shift down, causing the clamp to close via l4 and also air to be supplied to spring-returnair valve T12 which has its arrow to the left which is the plugged position. The clamp holds the sheeting in operative association with the empty core. The severing member is in operative association with the sheeting and empty core.

Air is also being supplied from T11 to pressureoperated electrical switches PS-3 and PS-4. This causes the needle in PS-3 to shift down and start the means for heating the severing member heating via line H-6. The needle in PS4 is also shifted down and this starts the dwell timer timing via 1-1-7. The dwell timer via an electrical signal through G-2 causes the arrow in solenoid valve SV-3 to shift down. .The heating of the severing member causes the sheeting to be severed, the newly severed end ofthe running length of sheeting to be heat bonded to the empty core, and the end of the sheeting which is attached to that wound on thecore containing a certain length of sheeting to drop away from the empty core.

Air from T11 is allowed to pass through spring-return air valve T13 when its cam follower is actuated by the cam sequencer immediately after the cam sequencer has finished actuating T7. The air flowing through T13 is the air supply for solenoid valve SV-3. The dwell timer causes the arrow in SV-3 to be in the down position until the dwell period has ceased indicating that heating is over via line G-2 from the electrical system. T13 is actuated by the cam sequencer and air flows to SV-3 before the dwell period is over. When dwell is over, the arrow on SV-3 shifts up and air flows through air shuttle V7 to V16 and to the top of R8 causing the arrow in R8 to be shifted down and the air from the top of the cylinder 37 to be vented off.

The shifting of the arrow in R8 causes air to flow into the bottom of cylinder 37 causing the piston 61 to be lifted; thereby lifting the severing unit. The severing unit lifts until it contacts the contact follower on T12 which causes its arrow to be shifted to the right causing air to flow to R9 which has its arrow up allowing air to flow to R8. This causes air to flow to the top of piston 61 while air is also flowing to its bottom and therefore the piston stops at this point. At this point the severing member is about an inch above the empty core and the clamps have extended thereby continuing hold the sheeting to the core. The sheeting has been severed and the end of the continuous sheeting heat-bonded to the core.

The air flowing from the outlet of R9 also flows to air relay R11 which causes its arrow to shift down causing the cooling air jets to come on via 15. The cooling blast of air is directed to the heat bond betweenthe sheeting and the core. The air cooling continues until the accumulator trips the contact follower on spring-return air valve T14 which gets its air supply from the accumulator control system via U indicating the accumulator is full to a certain predetermined degree. This causes the.

arrow in T14 to shift right causing air to flow to air relay R12 causing its arrow to shift left causing air to flow through it, through air shuttle V8 to R9 causing its arrow to shift down thereby allowing the severing unit to rise via the air pressure on the bottom of cylinder 37 pushing up piston 61. Air flows from R12 through V8 and V7 to R8 to cause its arrow to move down in case it is not down already which it normally would be at this point in the cycle.

Air from R12 also flows to R10 causing its arrow to be shifted up thereby causing the clamps to be opened via 16 and to R11, causing its arrow to be moved up to the top position thereby shutting off the cooling air jets. A pulse of air also flows from R12 through air shuttle V5 through T10 and to PS-2 and causes its needle to be shifted down causing the core to rotate via H-5 and take up the slack in the sheeting. This is a predetermined amount set by the electrical system.

Air from R12 also flows via V3 to T8 and R6 to start the cam sequencer operating again via R7 at normal speed 13. The cam sequencer was shut off by the above described second lobe on the cam sequencer for actuating T2 which actuated T2 during the cooling part of the cycle. SV-2 lost its air when T1 was actuated as described above and therefore there was no resistance to T2 stopping the cam sequencer when it was actuated.

At this point when the severing unit reaches its top position out of the general path of movement of the sheeting, it contacts the ball follower on T4, thereby, causing its arrow to shift right (ithaving shifted left when the severing unit went down) and causing air to flow'to T3. The arrow in T3 is to the left because the rider roll is up; therefore, the air flows through T3 to T5. The air also pushes the needle in-PS-l down but since there is no signal from the footage counter via G-l, no signal passes out H-l.

Therefore, air is flowing to T5. The cam sequencer actuates the cam follower on T5 causing the arrow to shift left. This causes air to flow to pressuraoperated electrical switch PS-S causing the needle to move down causing electricv current to flow via line 1-1-8 to cause the motor which rotates the turret to rotate it in the direction toward the general path of movement of the sheeting such that the empty core is rotated into winding position and the core containing a certain amount of sheeting is in position for removal' The rotation is stopped when the spindle containing the empty core contacts the contact follower of electrical limit switch LS-4 causing its needle to shift left and electric current to flow via line 11-9 to stop the movement of the turret.

The electric current also flows to electrical limit switch LS- which indicates to the electrical system via H- or H-ll which spindle is in winding position. If it is one, it will cause the contact follower of LS-S to cause the needle to shift left and current to flow through H-10. If it is the other, the needle will stay as is, and the spindle will be indicated by l-l-l 1.

Electric current from LS-4 also flows to solenoid valve SV-4 which causes its needle to move down so that air flows through it to spring-return air valve T15. The cam sequencer has moved the arrow in T to the right so air flows through it and through shuttle valve V9 to R4 thus causing its arrow to move back to the up position causing air to fill the upper portion of cylinder 59, pushing piston 60 down. This causes the rider roll 6 to move down.

When the rider roll gets to the proper position for winding on top of the core, it stops and piston 60 contacts the contact follower of spring-return air valve T16 causing its arrow to be shifted to the right (this can only happen if there is an empty core) causing air to flow via V14 to pressure-operated electric switch PS-6 which causes its needle to move down so that electrical current is sent via 1-1-12 to the correct motor to rotate the empty core at overspeed. 1-1-12 also starts the sheet forwarding means between the accumulator unit and windup unit operating. The electrical system which causes the core to rotate at overspeed via 1-1-12 causes it to rotate at overspeed until accumulator is emptied to a predetermined degree and then gradually slows to normal line speed at which point the accumulator is empty and the cycle is completed.

SU is an air throw switch which puts the system in mode for a normal automatic repeat out if set so that the air flows from the top outlet line to spring-return air valve T17 which is actuated by the cam sequencer immediately after T1 is actuated. It allows for a repeat cut for a certain predetermined period.

The air flows from T17 to air switch D2 which is the switch which actuates repeat cut. If it is pushed, air flows to R3 causing its arrow to be pushed to the right. This causes air to flow to spring-return air valve T18 which causes the empty core to rotate via PS-2 so that the cut is not in the same position on the core. The air from D2 also shifts the arrow in R7 to the right causing the cam sequencer to operate at accelerated speed via 17. Air passes from R7 through air shuttles V10 and V8 to put the arrows in the severing unit controls R9 etc. in position as though the normal cutting sequence is over, i.e., in their normal winding positions. The air from D2 also causes R5 to have its arrow shifted down thus putting the rider roll on manual control via air switches D3 and D4. The air from R5 also flows via Q to air switches D5 which flows through air shuttles V15 to D5 and D6 which allows for manual operation of the severing unit. The manual control put on the rider roll and severing unit are on so that they will not operate while the cam sequencer is at overspeed. The cam sequencer contacts spring-return valve T19 when the overspeed cycle is almost completed so that R7 is put back into position for normal operating speed and manual control is removed.

A safety device in the system is spring-return air valve T which is actuated by the cam sequencer and will cause the severing unit to come up if via T11 it is found that the core containing a certain amount of sheeting is in the severing position when the severing unit is lowered. This is possible because if T11 hasn't been actuated by the severing unit in the predetermined amount of time, T20 automatically lifts the severing unit. T11 can only be actuated if a core is at the cutting position.

The system can be run manually utilizing air switches D7, D8 (flowing through V11), D3, D4, D5, D6 and D1. To reset to automatic after a manual run, air switch D9 is used. The air from D9 flows through air shuttle V12 to R3 and through air shuttle V13 to RS and R7, through air shuttle V10 and V8 to T8, R6, R9, R10 and R11 and through air shuttle V7 and V16 to R8.

To set the system in a mode for a manual hand-cut and hand-overlap type start on a core when the rest of the system is in automatic mode, SU is shifted to the bottom position. This takes the severing unit and PS-2 out of the system by moving the arrows in T6 and T10 to the right and puts air at air relay R13. When air passes through T20 by operation of the cam sequencer which is still in the system, Rl3s arrow is moved to the right and air flows to pressure-operated electrical switch PS-7 causing its needle to move down and a predetermined rotation of the empty core and operation of the sheet forwarding means between the accumulator unit and windup unit to begin via line 11-13. This allows the operator to make the manual cut and start. The normal automatic sequence begins again when the accumulator indicates via T14 that it is full to a predetermined level. The sequence of operation is the same as described above from that point except that PS-2 is not actuated, the severing unit is not operated (remaining in its normal winding position), andthe core rotates at its predetermined rate through its movement to the normal winding position and the lowering of the rider roll. Air from T16 causes the arrow in R13 to shift back to the right.

T21 is a safety device and is actuated, i.e., its arrow is shifted down when the accumulator is full as determined by the contact follower on spring-return air valve T21 which gets its air from the accumulator system via X. The air from T21 passes through air shuttle V14 to PS-6 and starts the empty core rotating at overspeed via 1-1-12. If there has been a manual cut and start, T16 hasnt moved the arrow in R13 to the left and T21 has been actuated, the arrow in R13 will be moved to the leftby the air from T21.

The above description is a description of a preferred embodiment of the invention. Many variations and modifications within the spirit of the invention will appear to those skilled in the art and such are considered to fall within the scope of the following claims.

The invention claimed is:

l. A system for automatic handling a running length of thermoplastic sheeting from a processing unit to form a series of individual rolls, said system comprising in combination and positioned along the general path of movement of the sheeting an accumulator unit cooperating with the processing unit;

sheet forwarding means cooperating with the accumulator;

windup promotion means cooperating with the sheet forwarding means;

a windup unit cooperating with the windup promotion means, said windup unit comprising means for moving a core containing a certain length of sheeting away from the general path of movement of the sheeting and replacing said core containing a certain length of sheeting with an empty core after moving the core containing a certain length of sheeting away from the general path of movement of the sheeting thereby unwinding some sheeting from the core containing a certain length of sheeting and moving the empty core towards the general path of movement until the empty core overlaps the sheeting and is in position to engage a severing unit; a severing unit cooperating with windup unit and positioned along the general path of movement of the sheeting, said severing unit comprising in combination (a) a severing wire for severing the sheeting and heat bonding the end of the running length of sheeting to the empty core, (b) means for heating said severing wire, (c) means for moving said severing wire, ((1) means for holding the severing wire in operative association with the sheeting and empty core during severing and heat bonding, (e) means for clamping said end of sheeting to said empty core, a positioning means for moving said severing unit into contact or away from the sheeting where it overlaps the empty core, and (f) means for cooling the severed end of the running length of sheeting which is heat bonded to the empty core; and control means cooperating with said accumulator, sheet forwarding means, windup promotion means, windup unit and severing unit to cause the accumulator unit to collect the sheeting from the processing unit which continues to operate while the core containing a certain length of sheeting is automatically moved from the general path of movement of the sheeting while the empty core is moved toward the general path of movement of the sheeting until it overlaps the sheeting, the sheet severed, the end of the running length of sheeting heat bonded to the empty core and the empty core moved into the general path of movement of the sheeting, said control means comprising in combination (a) a footage counting means which determines when a certain length of sheeting has accumulated on said core, (b) means for actuating the accumulator unit such that the accumulator unit begins to collect the sheeting from the processing unit when the footage counting means indicates a certain length of sheeting is on the core, (c) means for ceasing the movement of the sheet forwarding means between the accumulator unit when the footage counting means indicates a certain length of sheeting is on the core, (d) means for actuating the windup promotion means when the footage counting means indicates that a certain length of sheeting has accumulated on the core and moving the windup promotion means away from the general path of movement of the sheeting. (e) means for detecting when said moving of the windup promotion means is in position for a core change, (f) means for actuating the windup unit so that the core containing a certain length of sheeting is moved away from the general path of movementof the sheeting, unwound to a degree such that the core containing a certain length of sheeting can be moved out of the general path of movement and the empty core moves towards the general path of movement when the means for actuating the windup promotion means indicates that the windup promotion means is in position for a core change,

(g) means for stopping the movement of the windup unit when the empty core is in position under the severing unit, (h) means for causing the windup unit to rotate or cease to rotate the empty core when the empty core is positioned under the severing unit, (i) means for causing the means for moving the severing wire into operative association with the empty core and overlapping sheeting to move the severing wire into operative association with the empty core and sheeting when the empty core has ceased to rotate, (j) means for holding the severing wire in operative association with the sheeting and empty core when the severing wire has contacted the sheeting which is in contact with the empty core, (k) means for causing the means for heating the severing wire to heat when the means for holding the severing wire in operative association with the sheeting and the empty core are in position (1) means for causing the means for holding and the means for moving the severing wire to move the severing wire from operative association with said sheeting and empty core while the means for holding said severing wire in operative association with the sheeting and empty core continues to hold the sheeting to the empty core so that the means for cooling the severed end of the running length of sheeting which is heat bonded to the empty core can operate effectively when the heating means have heated the severing wire for a predetermined amount of time and the heating has ceased, (m) means for causing said clamping means to hold said severed end to the empty core when said severing wire is in operative assocation with the sheeting, (n) means for starting said means for cooling the severed end of the running length of sheeting which is heat bonded to the empty core, to cool after the means for holding and means for moving the severing wire have moved the severing wire from operative association with the sheeting and empty core, (0) means for causing the severing unit and the means for holding the severing wire in operative association with the sheeting and empty core to move away from the general path of movement and into their positions for normal winding, (p) a filling detector means which indicates the level of accumulated sheeting the accumulator unit, (q) means for causing the cooling to stop cooling when the accumulator is filled to a certain degree, (r) means for causing the means for clamping the severed end to release when the cooling is stopped, (s) means for causing the windup unit to move the empty core into normal winding position when said severing unit is in normal winding position, (t) means for causing the windup unit to rotate said empty core at least one revolution while said windup unit is moving the empty core to the normal winding position. (u) means for causing the windup promotion means to move to the general path of movement of the sheeting to the normal winding position when the empty core is in normal winding position, (v) means for causing the sheet forwarding means to commence operation when the windup promotion means is in normal winding position, (w) means for causing the windup unit to cause the empty core to rotate at a speed above normal winding speed such that the accumulated sheeting in said accumulator unit is depleted when the windup promotion means is in normal windup position, (x) means for causing the windup unit to rotate the empty core at normal winding speed when said accumulator unit no longer contains any accumulated sheeting.

Claims

1. A system for automatic handling a running length of thermoplastic sheeting from a processing unit to form a series of individual rolls, said system comprising in combination and positioned along the general path of movement of the sheeting an accumulator unit cooperating with the processing unit; sheet forwarding means cooperating with the accumulator; windup promotion means cooperating with the sheet forwarding means; a windup unit cooperating witH the windup promotion means, said windup unit comprising means for moving a core containing a certain length of sheeting away from the general path of movement of the sheeting and replacing said core containing a certain length of sheeting with an empty core after moving the core containing a certain length of sheeting away from the general path of movement of the sheeting thereby unwinding some sheeting from the core containing a certain length of sheeting and moving the empty core towards the general path of movement until the empty core overlaps the sheeting and is in position to engage a severing unit; a severing unit cooperating with windup unit and positioned along the general path of movement of the sheeting, said severing unit comprising in combination (a) a severing wire for severing the sheeting and heat bonding the end of the running length of sheeting to the empty core, (b) means for heating said severing wire, (c) means for moving said severing wire, (d) means for holding the severing wire in operative association with the sheeting and empty core during severing and heat bonding, (e) means for clamping said end of sheeting to said empty core, a positioning means for moving said severing unit into contact or away from the sheeting where it overlaps the empty core, and (f) means for cooling the severed end of the running length of sheeting which is heat bonded to the empty core; and control means cooperating with said accumulator, sheet forwarding means, windup promotion means, windup unit and severing unit to cause the accumulator unit to collect the sheeting from the processing unit which continues to operate while the core containing a certain length of sheeting is automatically moved from the general path of movement of the sheeting while the empty core is moved toward the general path of movement of the sheeting until it overlaps the sheeting, the sheet severed, the end of the running length of sheeting heat bonded to the empty core and the empty core moved into the general path of movement of the sheeting, said control means comprising in combination (a) a footage counting means which determines when a certain length of sheeting has accumulated on said core, (b) means for actuating the accumulator unit such that the accumulator unit begins to collect the sheeting from the processing unit when the footage counting means indicates a certain length of sheeting is on the core, (c) means for ceasing the movement of the sheet forwarding means between the accumulator unit when the footage counting means indicates a certain length of sheeting is on the core, (d) means for actuating the windup promotion means when the footage counting means indicates that a certain length of sheeting has accumulated on the core and moving the windup promotion means away from the general path of movement of the sheeting, (e) means for detecting when said moving of the windup promotion means is in position for a core change, (f) means for actuating the windup unit so that the core containing a certain length of sheeting is moved away from the general path of movement of the sheeting, unwound to a degree such that the core containing a certain length of sheeting can be moved out of the general path of movement and the empty core moves towards the general path of movement when the means for actuating the windup promotion means indicates that the windup promotion means is in position for a core change, (g) means for stopping the movement of the windup unit when the empty core is in position under the severing unit, (h) means for causing the windup unit to rotate or cease to rotate the empty core when the empty core is positioned under the severing unit, (i) means for causing the means for moving the severing wire into operative association with the empty core and overlapping sheeting to move the severing wire into operative association with the empty core and sheeting when the empty core has ceased to rotate, (j) means for holding the severing wire in operative association with the sheetIng and empty core when the severing wire has contacted the sheeting which is in contact with the empty core, (k) means for causing the means for heating the severing wire to heat when the means for holding the severing wire in operative association with the sheeting and the empty core are in position (l) means for causing the means for holding and the means for moving the severing wire to move the severing wire from operative association with said sheeting and empty core while the means for holding said severing wire in operative association with the sheeting and empty core continues to hold the sheeting to the empty core so that the means for cooling the severed end of the running length of sheeting which is heat bonded to the empty core can operate effectively when the heating means have heated the severing wire for a predetermined amount of time and the heating has ceased, (m) means for causing said clamping means to hold said severed end to the empty core when said severing wire is in operative assocation with the sheeting, (n) means for starting said means for cooling the severed end of the running length of sheeting which is heat bonded to the empty core, to cool after the means for holding and means for moving the severing wire have moved the severing wire from operative association with the sheeting and empty core, (o) means for causing the severing unit and the means for holding the severing wire in operative association with the sheeting and empty core to move away from the general path of movement and into their positions for normal winding, (p) a filling detector means which indicates the level of accumulated sheeting the accumulator unit, (q) means for causing the cooling to stop cooling when the accumulator is filled to a certain degree, (r) means for causing the means for clamping the severed end to release when the cooling is stopped, (s) means for causing the windup unit to move the empty core into normal winding position when said severing unit is in normal winding position, (t) means for causing the windup unit to rotate said empty core at least one revolution while said windup unit is moving the empty core to the normal winding position, (u) means for causing the windup promotion means to move to the general path of movement of the sheeting to the normal winding position when the empty core is in normal winding position, (v) means for causing the sheet forwarding means to commence operation when the windup promotion means is in normal winding position, (w) means for causing the windup unit to cause the empty core to rotate at a speed above normal winding speed such that the accumulated sheeting in said accumulator unit is depleted when the windup promotion means is in normal windup position, (x) means for causing the windup unit to rotate the empty core at normal winding speed when said accumulator unit no longer contains any accumulated sheeting.