GB2468536A

GB2468536A - Coil winding and wrapping apparatus

Info

Publication number: GB2468536A
Application number: GB0904359A
Authority: GB
Inventors: Peter Renwick
Original assignee: PIPECOIL TECHNOLOGY Ltd
Current assignee: PIPECOIL TECHNOLOGY Ltd
Priority date: 2009-03-13
Filing date: 2009-03-13
Publication date: 2010-09-15
Anticipated expiration: 2029-03-13
Also published as: GB0904359D0; EP2406162A1; GB2468536B; WO2010103336A1

Abstract

Coiling winding apparatus comprises spaced apart first and second rotatable and driven coil winding members (401 fig 4a) arranged to rotate about a common axis (413 fig 4a) and a film dispenser 424, 425 arranged to dispense film 423 to wrap a finished coil 422 as it is wound. The first and second coil winding members 401 each include at least one support element (409 fig 4a) configured to support an elongate element as it is being wound into a coil, and a plurality of retractable members 428 supporting the sides of the 422 coil during winding. A controller may move the side support members 428 between the extended and retracted positions, to support the sides of the finished coil 422 without falling in the path of the film 423 during application thereof to the finished coil 422.

Description

Apparatus for Coiling an Elongate Element

Field of the Invention

The present invendon relates to apparatus for coiling an elongate element, and in pardcular to such an apparatus which includes a film wrapping system for packaging the coils.

Background of the Invention

Coiling machines are used to produce a coiled package as part of the manufacture of such products as plastic pipe, electric cable or steel wire. This patent application will refer mainly to pipe coiling but the techniques described throughout can apply to any product that is packaged as a coil.

These coils are typically secured by means which include the following: Wire, cable or string des, applied either manually or automatically; Plastic or steel straps, applied either manually or automadcally; and Stretch film wrapping, an industrial method with some similarity to the use of household cling film.

Pipe manufacturers typically produce a range of different sizes of pipe and therefore, to minimise investment costs, coiling machines typically have to be able to produce a range of sizes of coil. This requires that the width and diameters of the packaged coil can easily be altered. A machine that packages coils should ideally cater for a variety of coil sizes.

Large sizes of pipe or wire are manufactured slowly enough for the coils to be secured using manual methods. Smaller sizes of pipe are manufactured more quickly and require automated methods of securing the coil. Figure 1 illustrates a small coil (101) secured by plasdc straps(1 03) and a smaller coil (102) secured by string ties (104). Definitions of surfaces of a coil are defined in Figure 1 as inside surface (105), side (106) and outside surface (107). Automatic strapping machines cannot secure coils less than 3 inches wide due to the width of the strapping head but have no problem with wide coils. Small coils of very small diameter pipe such as the 6mm outside diameter (OD) micro-bore tubing typically used for drip irrigation systems are too small (with respect to the size of the section to be tied) to be strapped by automatic strapping machines. Wire tying machines are restricted to a maximum width of around 2 inches and 2 inches deep. The variation in the size capability between strapping and wire tying machines limits the range of coil sizes that a coiling machine can produce if it is to avoid having to be fitted with a variety of tying/strapping devices.

String tying is at present an operation performed off line that requires manual insertion and indexing of the coil into and around the string tying machine. Automatic strapping and tying machines are mechanically complex, subject to breakdowns and require a high level of maintenance. Each strapping or tying operation requires the strapping/tying mechanism to advance to the outer edge of the coil, deploy guides for the strap, send the strap round the guides, pull the strap tight, form a joint and cut off the tied strap. This operation has to be repeated for each of however many straps are applied. This is a time consuming operation which is too slow to keep pace with the speed of manufacture of micro-bore tubing.

The advantage of film wrapping over straps or ties is that film can be more quickly applied using less costly and less complicated machinery. Film wrapping can cope with a wide range of coil widths and diameters. However the manner in which film wrapping coil wheels are operated at present places a limitation on the dimensions of the coil, namely that it is difficult to form a coil whose internal diameter (lID) is less than approximately ?O% of the outside diameter (OD) of the coil. This has ramifications with respect to the volumetric storage requirements of the packaged coils.

It is desirable to consider an alternative that allows for a smaller ID of the coil in relation to the OD of the coil. It would also be desirable for such an alternative to allow for easy adjustment of coil width and inside diameter without employing manual means of adjustment or the addition/ removal of extra components to cater for variation in coil dimensions.

The difficulties encountered in developing a simpler alternative are discussed with reference to a prior art coil wheel for wrapping the coil with film to be referred to as a film wrapping coil wheel and a prior art coiling machine for securing the coil with straps to be referred to as the FB Balzanelli system The prior art film wrapping coil wheel will now be described with reference to the accompanying drawings, in which:-Figures 2a and 2b are perspective views of the prior art film wrapping coil wheel; and Figure 2c is a perspective view of the prior art film wrapping coil wheel including a spool of film applying wrapping to a coil of pipe.

The prior art film wrapping coil wheel is a single coil wheel that grips the beginning of a length of pipe as it is delivered from manufacture, winds this up as a coil of pipe and then wraps the coil in film both on the outside surface and on the sides of the coil.

Figure 2a 2b and 2c show a simplified representation of the prior art film wrapping coil wheel procedure. Fig 2a shows a coil wheel frame (201) mounted on the main shaft (202). Radiating from the centre of the coil wheel frame are four rails (205) on which both the four ID support members (206) and the four side arm mountings (207) are able to slide.

Onto each side arm mounting (207) is fitted an inner side arm (208), defined as the side arm closest to the coil wheel frame (201) and an outer side arm (209) defined as the side arm furthest from the coil wheel frame (201). The position of each inner side arm (208) governs the width of the coil and each is adjusted by means of a nut (210). Each side arm mount (207) is connected to an ID support member by a pneumatic actuator comprising a cylinder (218) and a rod 219). Retracting this actuator (218 & 219) causes the side arms (208 & 209) to project beyond the ID support members (206) thus forming supports for the sides of the coil (221) as it is formed.

The ID of the coil can be adjusted as follows. Referring to Figure 2b each of the ID support members (206) can be adjusted in relation to the axis (212) of the coil wheel assembly by the rotation of each radial lead screw (213). The rotation of each lead screw (213) is synchronised as follows to give equal travel for each ID support member (206). Each lead screw terminates in a gearbox (214) one of which (214a) has an input shaft (215). When this is rotated, as well as rotating the lead screw under this gearbox (214a), it causes the four intermediate drive shafts (216) to rotate, using Hooke's joints (217) to transmit rotation through an angle. This rotation causes the remaining gearboxes (214) to turn the remaining lead screws (213) at the same speed as the first one, thus synchronising the radial movement of the ID support members (206).

In order to wind up the pipe into a coil the whole coil wheel assembly (211) shown in Figure 2a is rotated about the axis (212). The means of providing this rotation is not illustrated but it is typically provided by a chain drive or a toothed rubber belt drive. Fitted to one of the side arm mountings (207) is the pipe grip actuator (222) which causes the grip finger (223) to move towards the outer side arm (209) trapping the beginning of the pipe (not shown) before the winding operation commences.

Figure 2c shows the fully formed coil (221) supported by side arms, the outer side arm (209) and the tip of the inner side arm (208) being visible. Film (224) is shown being drawn off the film spool (225) and applied to the coil (221). Towards the end of the winding operation film is drawn down from the reel of film (225) by two film feed rollers (226) and lowered until with the assistance and guidance of air jets (not shown) it is brought into contact with the rotating coil (221) whereupon the properties of the film cause it to cling to the coil. Rotating the coil wheel assembly (211) draws the film around the coil (221). When one revolution has been completed the coil wheel assembly (211) continues rotating and a braking resistance is applied to the film spool (225) which stretches the film and causes it to wrap around the sides of the coil as well as the outside surface of the coil.

When a sufficient number of layers of film have been applied, the film is cut. At this stage the side arms (208 & 209) have been trapped under the layers of film where they obstruct removal of the film. Extending all of the four pneumatic actuators (218 & 219) causes the side arms (208 & 209) to retract below the ID support members (206) thus withdrawing support for the sides of the coil (221).

Since the sides of the coil are now wrapped this support is no longer required. To discharge the film the ID support members are moved inwards to slacken their grip on the coil and then the coil is pushed off the coil wheel assembly (211). The device for pushing the coil off the coil wheel is not illustrated.

Whilst the arrangement described with reference to figures 2a, 2b and 2c is an effective method of facilitating the film wrapping of coils, the need to provide space for the side arms (208 & 209) and the side arm mounting (207) to retract towards the centre of the coil wheel assembly (211) limits how small the ID of the coil can be in relation to its OD. Increasing the OD of a coil will require longer side arms. Longer side arms will need more space in the centre of the coil wheel assembly in order to retract below the ID support member and this requirement will in turn dictate that that the ID must also be increased. This means that it has proved difficult to design a coil wheel assembly, using this method of film wrapping, which is able to produce a coil whose ID is significantly below 70% of the coil OD.

The disadvantage of producing such coils is that such coils make an inefficient use of storage space. By way of example a 20 inch OD coil with an ID of 14 inches (70% of OD) will have a void in the centre whose volume is 49% of the volume taken up by the coil including the void. If one were to reduce the ID tolO inches (50% of OD) a 20 inch OD coil will have a void in the centre whose volume of 25% of the volume taken up by the coil including the void. This would represent a 47% increase in volume of coiled pipe for the same OD. The calculation is as follows lOO%-25% 75/o l47% a 47% increase in volume of the coiled material 1OO%49% 51% The prior art FB Balzanelli system will now be described with reference to the accompanying drawings, in which:-Figures 3a 3b and 3c are perspective views of the FB Balzanelli system in different stages of operation.

The FB Balzanelli system is a coiling machine that secures the coil with straps.

The FB Balzanelli system describes a single coil wheel combined with a holding plate. The coil wheel grips of the beginning of a length of pipe as it is delivered from manufacture, winds this up as a coil of pipe and then applies straps to the coil in film at 4 locations around the coil.

The FB Balzanelli prior art coiling machine will be described with reference to Figures 3a 3b and 3c.

Figures 3a 3b and 3c are perspective views of the FB Balzanelli prior art.

Figure 3a 3b and 3c show a coil wheel suitable for a strapping procedure.

The coil wheel (301) comprises a coil wheel frame (302) mounted on the main shaft (303).

The coil wheel is mounted on an arm (304) coaxially with a rotating support plate (305) which is also mounted on an arm (304). The rotating support plate (305) has 4 cut-outs (306, 3 visible) to accommodate the strapping device that wraps the strap around the coil in the open space created at the position of arrow (307). Each arm (304) is mounted on a rail (308), a sliding arrangement that allows the distance between the coil wheel and the rotating support plate (305) to be varied. The means of achieving this variation is not depicted but it would be achieved typically by a motorised lead screw. This arrangement allows the coil wheel (301) and the rotating support plate(305) to be moved apart to the unload position as shown in fig 3b or moved together into the coil winding position as shown in figure 3c.

The coil wheel is rotated from an external source of rotation; the rotating support plate (305) is rotated by engagement with the dog teeth (313) on the centre shaft of the coil wheel (301).

Radiating from the centre of the coil wheel frame are four rails (309) on which the four ID support members (310) are able to slide. Adjustment of these ID support members is by the same method as described for the ID support members on the film wrapping prior art coil wheel as described with reference to 2a and 2b.

Mounted on each ID support plate (310) is a side arm (311) to support the side of the coil (313). To adjust the width of the coil, each side arm can be moved along the ID support plate (310) and fastened by means of one or more nut(s) and bolt(s) (312).

It is desirable to consider an alternative that allows film wrapping of coils who's ID is not significantly affected by the OD of the coil.

Preferred embodiments of the present invention seek to alleviate or overcome at least some of the disadvantages of the prior art film wrapping coil wheel mentioned above, namely, the complexity and inadequate speed of strapping and tying systems as applied to the high speed coiling of micro-bore pipe and the inability of film wrapping systems to wrap coils whose ID is significantly smaller than its OD.

Detailed Description of the Examples illustrated in the Drawings Preferred embodiments of the present invention will now be described, by way of example only and not in any limitative sense, with reference to the accompanying drawings, in which:-Figures 4a, 4b, 4c, 4d, 4e, 4f 4g and 4h are views of a preferred embodiment of the present invention perceived from one perspective; Figures 4i shows the derivation of a sectional view of a preferred embodiment of the present invention; Figures 4j and 4k show enlargements of the sectional view including the beginning of the pipe to be coiled; and Figures 5a and 5b are perspective views of an alternative preferred embodiment of the present invention.

Figure 4a shows a pair of coil wheels (401) suitable for a film wrapping procedure. Each coil wheel (401) comprises a coil wheel frame (402) mounted on the main shaft (403). The coil wheels are each mounted on arms (405 and 406) and coaxially oppose each other. Each arm (main shaft (403). The coil wheels are each mounted on arms (404 and 405) that in turn slide on a rail (406), a sliding arrangement that allows the distance between each coil wheel to be varied. The means of achieving this variation is not depicted but it would be achieved typically by a motorised lead screw is arrangement allows the coil wheels to be moved apart to the unload position as shown in Fig 4a or moved together into the coil winding position as shown in Figures 4e and 4h.

The coil wheels are rotated in the direction of the arrow (407), at least one thereof being powered from an external source of rotation, the other coil wheel being driven either by engagement with the first said coil wheel or by a separate drive, coordinated to rotate at the same speed to the first coil wheel. Referring to Figures 4a and 4c, radiating from the centre of the coil wheel frame are four rails (408) on which the four ID support members (409) are able to slide.

Referring to Figures 4b and 4c, onto each ID support member (409) is mounted a pneumatic actuator (410), shown with the head (411) extended. On the head of the pneumatic actuator (411) is fitted a side arm (412).

The ID of the coil can be adjusted as follows. Referring to Figure 4a each of the ID support members (409) can be adjusted in relation to the axis (413) of the coil wheel assembly by rotation of each radial lead screw (414). The rotation of each lead screw (414) is synchronised as follows to give equal travel for each ID support member (409). Each lead screw terminates in a gearbox (415) one of which (41 5a) has an input shaft (416). This input shaft (416) would be rotated by a motorised drive which for the sake of clarity has not been depicted. When this shaft (416) is rotated, as well as rotating the lead screw (414) under this gearbox (415a), it causes the four intermediate drive shafts (417) to rotate, using Hooke's joints (418) to transmit rotation through an angle. This rotation causes the remaining gearboxes (415) to turn the remaining lead screws (414) at the same speed as the first one, thus synchronising the radial movement of the ID support members (409).

At least one of the ID support members includes a slot (419) to accommodate the start of the length of pipe to be wound. This slot (419) shown in figure 4c may be tapered to facilitate easy insertion of the start of the pipe (420). The pipe (419) is advanced and positioned near and in line with the slot (419) as shown in Figure 4f. When the coil wheels are moved together to the coil winding position as shown in Figure 4g, the end of the pipe, having been held stationary, enters the slot (419) ending up at the narrow end of the slot. The means by which the pipe is advanced and held in the required position is not shown since the technology for such devices is commonly understood within the industry. Once the start of the pipe is positioned in the slot (419), the pair of coil wheels commence rotation and consequendy the pipe (420) becomes gripped by the edges (426 and 427) of the slot and drawn round the coil wheel as shown in Figure 4k from a starting position as shown in Figure 4j.

In order to wind up the pipe into a coil the pair of coil wheel assemblies (411) shown in Figure 4a and 4e are rotated about the axis (413). The means of providing this rotation is not illustrated but it is typically provided by a chain drive or a toothed rubber belt drive. Whilst the pipe is being wound an automatic guiding arrangement guides the pipe onto the coil wheels to produce orderly layers. The guiding means is not shown since the technology for such devices is commonly understood within the industry and known as a "fleeting" device. Towards the end of the winding operation film is drawn down from the reel of film (425) by two film feed rollers (424) and lowered until, with the assistance and guidance of air jets (not shown), it is brought into contact with the rotating coil. The natural clinging properties of the film allow it to begin becoming wrapped around the coil. After one revolution the film will have become firmly attached to the coil allowing a partial braking torque to be applied to the film feed rollers (424), this has the effect of stretching the film so that it is pulled onto the sides of the coil as shown in figure 4e. To avoid the side arms becoming trapped under the layer of film (423) each of the said side arms is individually and sequentially retracted whilst the film is being drawn round the coil. Figure 4e shows two of the side arms that have been sequentially retracted (428). This allows the film to be wrapped around the coil without trapping the said side arm. Once the said side arm is past the zone where it could become trapped by the film, it is returned to its former position, re-establishing its support for the side of the coil When a sufficient number of layers of film have been applied, the film is cut. The coil wheels 401 are then moved apart and wrapped coil 422 removed from the apparatus.

Figure 5 shows an alternative pair of coil wheels that differ from the preferred embodiment previously described with reference to Figures 4a,4b,4c,4d,4e, 4i, 4j and 4k. This difference is in respect to the manner in which the side arms are withdrawn from supporting the side of the coil.

Figure 5a and Sb show the side arms (502) as pivoting on the support member (503). Under the influence of a pneumatic cylinder (504) the side arm (502) is held against the side of the coil (422) when the cylinder is extended. When the cylinder (504) is retracted the side arm (502a) pivots out of the way of the film (423) thus avoiding becoming trapped under the film (423). The sequence in which side arms are withdrawn and restored, while the film is being wrapped around the coil, is the same as that for the preferred embodiment that has been described with reference to Figures 4a,4b,4c,4d,4e, 4i, 4j and 4k By designing a coiling machine for film wrapping of coils, a pair of coiling heads is able to form coils with smaller internal diameters, relative to coil outside diameter than has been previously achieved. Further, by employing a pair of coil wheels to produce each coil, the dimensions of each coil can easily be adjusted without the addition or removal of components. Further by employing a slot to grip the beginning of the pipe the complexity of a powered gripping mechanism is avoided.

Claims

Claims Coiling winding apparatus comprising spaced apart first and second rotatable coil winding members arranged to rotate about a common axis, drive means arranged to rotate the first and second rotatable members, and a film dispenser arranged to dispense film to wrap a finished coil, wherein the first and second coil winding members each comprise at least one support element configured to support an elongate element as it is being wound into a coil, and a plurality of side support members configured to support to side of the coil during winding thereof wherein each side support member is movable between extended and retracted positions, wherein in the extended position the said member supports the side of the coil and in the retracted position said member is moved away from the side of the coil, the apparatus further comprising a controller configured to control the movement of said side support members between the extended and retracted positions, to support the sides of the finished coil without falling in the path of the film during application thereof to the finished coil.
2. Coil winding apparatus according to Claim 1, wherein the winding members comprise a plurality of support elements.
3. Coil winding apparatus according to Claim 1 or 2, wherein at least one of the first and second winding members is mounted for movement towards and away from the other winding member.
4. Coil winding apparatus according to any preceding claim, wherein the or each support element is mounted on the winding member for movement towards and away therefrom.
5. Coil winding apparatus according to Claim 4, wherein the or each support element is constrained to move in a direction substantially parallel to the common axis.
6. Coil winding apparatus according to any preceding claim, wherein the support elements are mounted to permit radial movement thereof with respect to the common axis.
7. Coil winding apparatus according to Claim 6, including a synchronisation mechanism configured to synchronise radial movement of the support elements such that each support element moves by the same distance.
8. Coil winding apparatus according to any preceding claim, wherein the side support members are mounted so as to move along an axis substantially parallel to the said common axis.
9. Coil winding apparatus according to any preceding claim, wherein the side support members are pivotally mounted, and wherein the said side support members pivot between said extended and retracted positions.
10. Coil winding apparatus according to Claim 8 or 9, wherein side support members are mounted on respective support elements.
11. Coil winding apparatus according to any preceding claim, wherein said first and second coil winding members each comprise a plurality of support elements.
12. Coil winding apparatus according to any preceding claim, wherein at least one of the support elements is adapted to receive an end of an elongate element to be wound into a coil by said apparatus.
13. Coil winding apparatus according to Claim 12, wherein the at least one element includes a slot to receive the end of the elongate element.
14. Coil winding apparatus according to any preceding claim, wherein the drive means includes a transmission configured to transmit rotational power from one to the first and second coil winding members to the other.
15. Coil winding apparatus according to Claim 14, wherein the transmission includes inter-locking members.
16. Coil winding apparatus according to Claim 15, wherein the support elements form the inter-locking members.
17. Coil winding apparatus according to any of Claims 1 to 15, wherein the drive means for the first and second coil winding members comprises independent and synchronised drive means associated with the first and second coil winding members respectively.
18. Coil winding apparatus according to any preceding claim, wherein movement of the support elements between the extended and retracted positions is synchronised such that during that part of the revolution of the coil where the film extends outward from the side of the coil the support elements are retracted and during that part of the revolution of the coil where the film lies against the side of the coil the support elements are extended.
19. Coil winding apparatus according to Claim 18, wherein the support elements are moved between their extended and retracted positions sequentially.
20. A method of winding an elongate element into a coil comprising the steps of: i) attaching an elongate element to a coil winding apparatus as claimed in any of Claims 1 to 19; ii) rotating the first and second coil winding members to wind the coil until the coil has reached a desired outside diameter; iii) presenting film emanating from a film dispenser up to the surface of the coil; iv) rotating the first and second winding members to rotate the coil, thereby drawing further film from the film dispenser to wrap the coil and puffing film onto the sides of the coil; v) as the coil is rotated moving each support element between a retracted position in which the support element lies outside of the path of the film as it is drawn onto the sides of the coil, and an extended position in which the support element engages with a side of the coil.
21. A method according to Claim 20, comprising the further step of selecting the radial position of the support elements with respect to the common axis of the first and second coil winding members to define the internal diameter of the resulting coil.
22. A method according to Claim 20 or 21, including the further step of positioning the support elements to define the width of the coil.
23. A method according to any of Claims 20 to 22, including the further step of separating the coiled elongate element from the elongate element remaining uncoiled.
24. A coil winding apparatus substantially as shown in, and as described with reference to, the drawings.