The invention relates to web winders and methods of operating web winders.

The closest prior art known to the applicant is the applicant's own prior web winder which is a slitter rewinder (sold under trademark Titan CT610). This slitter rewinder comprises a frame; at least one turret rotatably mounted in the frame. The turret incorporates a housing from which first and second winding spindles extend; the turret being rotatable between a first position where the first spindle is in a winding position and the second spindle is in an unloading position; and a second position where the first spindle is in an unloading position and the second spindle is in a winding position. A supporting member is provided for holding the spindle or spindles, which are in an unloading position. The supporting member may be removed laterally to reveal one or more spindles in a cantilevered configuration. Rewound packages or bales located on the spindles in the unloading position may then be removed.

Other web winders are disclosed e.g. in US 2, 769, 600 which is regarded as the closest prior art, as well as in US 4, 344, 504 and GB 2 028 744.

The problem, which the invention addresses, may be defined as how to improve support for the spindles in a turret web winder.

In a first broad independent aspect, the invention provides a web winder comprising a frame; at least one turret rotatably mounted in said frame; said turret incorporating a housing from which first and second winding spindles extend; said turret being rotatable between a first position where said first spindle is in a winding position and said second spindle is in an unloading position; and a second position where said first spindle is in an unloading position and said second spindle is in a winding position; characterised in that said web winder further comprises:

• a supporting arm which extends between said winding spindles and which is sufficiently spaced from said housing to allow webs to be wound onto said spindle; said supporting arm incorporating a first clamp for attaching to a first spindle and a second clamp for attaching to a second spindle; and
• means for releasing and closing said clamps dependent upon the rotation of said turret.

This configuration is particularly advantageous because it allows the spindles to be supported during the operation of interchanging the spindle in the winding position with the spindle in the unloading position. It also minimises spindle distortions due to the risk of bending the spindles. It also allows for the spindles to be of greater length than would otherwise be possible which would increase the capacity of the winder.

In a subsidiary aspect in accordance with the invention's first broad independent aspect, said means for releasing and closing incorporates a cam, which is operatively connected to said clamps. This allows the releasing and closing operation to occur dependent upon the rotation of the turret. It avoids the requirement, which may have otherwise been mandatory for separate driving of the releasing and closing of the clamps.

In a further subsidiary aspect, said clamps are bearing clamps. This allows the clamps to fulfil a dual function of supporting the spindles and clamping in a sufficiently loose fashion to accommodate rotation of the spindle relative to the clamp.

In a further subsidiary aspect, said cam is located co-axially with said turret housing when said clamps are attached to both winding spindles and said turret is rotated to interchange said spindles between winding and unloading positions. This configuration allows the clamp releasing and closing means to operate in conjunction with the rotation of the turret housing.

In a further subsidiary aspect, said supporting arm incorporates a mounting plate on which said clamps are mounted; and said clamps incorporate a first portion which is fixedly attached to said plate and a second portion which is displaceable relative to said first portion and which abuts against said first portion when said second portion bears load. This configuration is particularly advantageous because it allows the fixed first portion to bear vertical loading instead of the components, which secure the second portion to the mounting plate.

In a further subsidiary aspect, the web winder further comprises means for retracting and returning said supporting arm from and to the spindle in the unloading position when, in use, the supporting arm is attached to the spindle in a winding position and released from the spindle in the unloading position; whereby the spindle in the unloading position is supported at its proximal extremity and is sufficiently free at its distal extremity to be unloaded.

In a further subsidiary aspect, said supporting arm is rotatably mounted on bearings and at least one of said bearings is a one-way clutch. This configuration is particularly advantageous because it prevents slight reverse rotation of the system due to varying package weights.

In a further subsidiary aspect, the web winder comprises two turrets and corresponding supporting arms; and said means for retracting and returning said supporting arm incorporates linkage means for synchronizing the operation of retracting and returning said supporting arms. This configuration is particularly advantageous because it allows the retraction and the returning driving mechanism to be common to both turrets.

In a second broad independent aspect, the invention provides a method of operating a turret web winder according to any of the preceding aspects, comprising the steps of:

• winding a web on a first spindle;
• unloading bales from a second spindle from the extremity of said spindle located oppositely to said turret housing;
• supporting said winding spindles by said supporting arm; and
• automatically releasing and closing said clamps dependent upon the rotation of said turret.

This method is particularly advantageous because it allows the spindles to be supported during the interchanging operation between winding position and unloading position. It also allows bending to be minimised. It also allows the length of the spindles to be extended for a given operational requirement.

In a subsidiary aspect in accordance with the invention's second broad independent aspect, the method further comprises the step of retracting said supporting arm whilst being attached to the spindle in the winding position and released from the spindle in the unloading position. This allows the load to be removed laterally without any impediment.

In a further subsidiary aspect, the method further comprises the step of returning said supporting arm following unloading the spindle in the unloading position. This allows the supporting arm to support the spindle during its rotation back to the winding position.

In a further subsidiary aspect, the method further comprises the step of rotating said turret for interchanging said spindles between the unloading position and the winding position whilst the clamps are closed onto both spindles. This configuration is particularly advantageous because it allows the spindles to be supported during their rotation between their winding position and their unloading position.

In a further subsidiary aspect, the method further comprises the step of opening the clamp as the spindle approaches the unloading position. This allows the clamp to open in time for its removal for the unloading operation to take place.

In a further subsidiary aspect, the method further comprises the step of closing the clamp as the spindle departs from the unloading position towards the winding position. This maximises the period of attachment during the interchanging of positions.

• Figure 1 shows a perspective view of a turret winder;
• Figure 2 shows a perspective view of the supporting arm side of the turret winder of figure 1;
• Figures 3 and 4 show side elevations from the supporting arm side of the turret winder; figure 3 shows the supporting arms in engagement with both spindles whilst figure 4 shows the supporting arms in a retracted position from the spindle in the unloading position;
• Figure 5 shows a perspective view of a supporting arm and its clamping assembly;
• Figure 6 shows the supporting arm of figure 5 in an alternative perspective view;
• Figure 7 shows a supporting arm in a sectional view through line A-A of figure 8;
• Figure 8 shows a side elevation of the supporting arm and its main support bearing housing;
• Figures 9 and 10 show alternative side elevations of the supporting arm;
• Figure 11 shows a perspective view with a part cross-sectional portion of the main support bearing housing and a portion of the supporting arm.

Figure 1 shows a web winder, which may be a turret slitter re-winder. Winder 1 incorporates a frame, which may be formed of several vertical panels such as panels 2 and 3. The frame supports a large number of apparatus such as slitters, idle shafts and vacuuming apparatus. None of these is shown for simplicity and clarity of description for the specific improvements to the turrets. Turrets 4 and 5 are shown straddling between panels 2 and 3. Each turret incorporates a turret housing 6, which is rotatable about its central axis. Spindles 7 and 8 extend between the panels. Spindle 7 is in its winding position whilst spindle 8 is in its unloading position. The turret housing is rotatable anticlockwise in order to cause the spindles to interchange positions. This allows the winding operation to occur whilst the unloading operation is taking place. A supporting arm arrangement 9 is shown in a mode of operation where the winding spindle 7 is secured to bearing means and spindle 8 is located in a cantilevered position for unloading packages or bales.

The supporting arm arrangement 9 incorporates a mounting plate 10 extending between spindles 7 and 8 when its clamps 11 and 12 are attached to their respective spindles.

As shown in figure 5, mounting plate 10 incorporates a cut out portion 13 of sufficient size to accommodate the diameter of a spindle. Portion 14 which is located immediately beneath cut out portion 13 incorporates an upper bowed surface 15 corresponding in diameter to the spindle diameter. Located inwardly from the mounting plate, a first portion 16 of the clamp 11 is shown. Portion 16 incorporates a bowed upper surface 17 which also corresponds to the diameter of the spindle. The portion is immobilized relative to the lower portion of the mounting plate through appropriate fasteners 18 and 19. Portion 20 of clamp 11 is substantially C-shaped with a pivot point 21 located at its lower extremity in the unloading position of clamp 11 in figure 5. The underside 22 of portion 16 corresponds in shape to the inside surface 23 of the C-shaped portion 20. When the clamp is in its closed position as shown for clamp 12, the surfaces 22 and 23 are in a mating relationship so that any vertical load exerted on the C-shaped portion would be carried by the other portion of the clamp in order to avoid the load being carried by pin 24 at a central location along the mounting plate 10. A number of attachment points such as attachment point 25 are provided to secure a shaft 26 by using a number of appropriate fasteners such as fastener 50. As can be seen in figure 3, the axis of the mounting plate when the supporting arm extends between the spindles, is in line with the axis of rotation of the turret housing. Shaft 26 as shown in figure 6 extends through the main support bearing housing 27. At a location adjacent to the mounting plate, a cam-plate 28 is secured and immobilized relative to the support bearing housing 27. Housing 27 incorporates at a first extremity a support bearing such as a roller bearing 29 and at its opposite extremity a one-way clutch and a support bearing 30. The combined support bearing and one-way clutch mechanism provides the support which is necessary for shaft 26 as well as preventing slight reverse rotation of the system due to varying package weights.

Figure 5 shows the clamps in the horizontal position when the slitter is rewinding. The spindles and their supporting rotating centres are not shown for clarity. Clamp 12 corresponds to the configuration of the clamp when in the winding position. A tension spring 31 extends between C-shaped clamp portion 20 and link 32. Plate 33 and its oblong slot 34 protrude from the rear portion of C-shaped clamp portion 20. Plate 33 is secured through fasteners such as fastener 35 (see figure 9) onto the C-shaped clamp portion. As shown in either figure 5 or figure 9, tension spring 31 is extended for the configuration shown of clamp 12. Pin 36 fits into oblong slot 34. The configuration of clamp 12 in figures 5 and 9 enforces an over-centre condition which locks clamp 12 in position. Link 32 is connected through shaft 38 to link 37. Shaft 38 is supported by a bearing set into mounting plate 10.

The over-centre distance of link 32 is controlled by the abutment of link 37 against the stop-pin 39, which is fixed to mounting plate 10 (see figure 10). Link 37 also has a hardened pin 40 which is pressed in and which acts as a cam follower.

The path of cam-pin 40 is illustrated in figure 7. As the mounting plate is caused to rotate in the anticlockwise direction in conjunction with the turret, the cam-follower 40 follows an arc section 41 of the path. During this phase, clamp 12 remains in its closed position. As it nears the position where the spindle would be unloaded, cam-follower 40 abuts against opening cam 42, which causes link 32 to pivot and be held in the position shown for clamp 11. The tension spring draws the C-shaped portion 20 against link 32.

Once the clamp is opened as shown for clamp 11, the supporting arm is free to detach from the spindle in the unloading position.

The support bearing housing 27 is fixed to a supporting arm 43 (see figure 2), which pivots about the same axis as the spindle in its winding position. Arm 43 is rotatable about spindle 7 and allows the mounting plate 10 to be retracted from spindle 8 for unloading. Arm 43 incorporates two wings 44 and 45 located on either side of the winding spindle. A ram 46 is secured at one extremity 47 to frame 3 and at its opposite extremity to wing 45 so that when the ram is extended wing 45 is drawn upwards causing wing 44 to be lowered and retracted out of the unloading area. A linkage member 48 extends between wing 45 and a corresponding wing of another turret so that when the arm 43 is displaced a corresponding motion is achieved in the corresponding turret.

As the mounting plate 10 is rotated with the turret, cam-follower 40 engages closing cam 49 immediately after the rotation of the mounting plate is initiated when returning the unloaded spindle from the unloading position to the winding position.

Opening and closing cam 42 and 49 are configured as plates with individually adjustable mechanisms to allow the refinement of the operation.

When the cam-follower 40 meets the opening cam 49 pin 36 is forced along the slot (clockwise when viewing figure 9). This removes the over-centre lock and rotates the clamp portion 20 away from its secured position.

The continuation of rotation of the mounting plate 10 by another 180 degrees after ejection immediately causes cam-follower 40 to abut the closing cam 49 and re-lock the clamp portion 20 onto the bearing of the spindle it is supporting.

The operation of the re-winder may be summarised in overview as follows: The lifting arm 43 pivots about the same centre axis of the rewind spindle 7 in the winding position. A mounting plate 10 pivots on the lifting arm 43, and has the same axis of rotation as the main turret housing 6 on the opposite side of the re-winder. The mounting plate 10 has two bearing clamps 11 and 12, one at each end. A bearing on the end of the rewind spindle, in the winding position, is clamped by the bearing clamp 12, and secured by a mechanical linkage 32. The spindles rotate with the turret by 180 degrees anticlockwise. This also rotates the mounting plate 10 because both spindles are clamped by their respective bearing clamps 11 and 12. When the spindle approaches the unload position, a cam assembly automatically opens the bearing clamp 11. At the winding position, bearing clamp 12 remains closed. Since the bearing clamp 11 is released, the lifting arm is now free to rotate 90 degrees in a downward direction together with the mounting plate 10 because they both pivot about the same centre axis which corresponds to the axis of the spindle at the winding position. This action allows enough clearance for rewound packages to be removed from the spindle 8 in the unload position. After the rewound packages have been removed, the lifting arm 43 rotates 90 degrees in an upward direction and engages with the bearing on the end of the spindle 8. The main turret housing 6 now rotates the spindles 180 degrees anticlockwise and at the start of this rotation, the cam assembly automatically closes the bearing clamp 11 using the mechanical linkage 32.

This assembly is fitted to both the upper and lower main turret. They are mechanically linked together with a connecting rod or linkage member 48. The rotation of the arm 43 is achieved by using a hydraulic cylinder or ram 46 with its associated control valves.