WO2003074366A1

WO2003074366A1 - Apparatus for pressurising the contents of a bag

Info

Publication number: WO2003074366A1
Application number: PCT/EP2003/002256
Authority: WO
Inventors: Hans Herman Marinus Coenraad Weck
Original assignee: Sigmakalon Group B.V.
Priority date: 2002-03-07
Filing date: 2003-03-04
Publication date: 2003-09-12
Also published as: AU2003233794A1; GB0205354D0; EP1480884A1

Abstract

An apparatus for pressurising the contents of a bag (20), being a bulk package, comprising a bag (20) having a first end (30) and a second end (1) opposite thereto, a bag engaging element (22) adapted to engage with the said first end (30) of the bag (20) for mutual rotation therewith, actuating means (28) operable to drive the bag engaging element (22) about an axis of rotation which extends through the bag (20) between the said first and second ends thereof so that the engaging element (22) rotates the said first end (30) of the bag (20) about the said axis in a drive direction.

Description

APPARATUS FOR PRESSURISING THE CONTENTS OF A BAG

The present invention relates to apparatus for pressurising the contents of a bag and, in particular, but not exclusively, the contents of a bulk package such as an in-liner .

The bulk handling of viscous materials is carried out in a number of industries. In many cases, a cost effective and convenient means of transportation and storage of such materials is by the use of in-liners i.e. bags which can be transported in containers and loaded into dosing containers on the site of the user. Examples of industries which utilise in-liners include those which use: technical oils and greases; foodstuffs including oil, greases, butter, dairy products, peanut butter, mayonnaise, soup, etc; and plaster products. When utilising viscous materials, a common problem is to minimise the residue of the viscous material which is left in the in-liner and which must thereafter be discarded. Such waste material has environmental as well as economic disadvantages for the user.

Currently existing plaster materials are highly viscous and are typically supplied in bags of 25 kg. On location, these bags are emptied into a suitable container connected to dosing equipment. The dosing equipment is used to convey and atomise the plaster by pump so that it may be applied, for instance, on walls and ceilings. 25 kg bags are supplied for manual handling and a device is supplied for either manual or electrically powered emptying of the bag utilising a device known as a twin roller wringer. The twin roller wringer is an attempt to minimise residues left in the bags.

The manual handling of bags of such weight is becoming increasingly problematic due to health and safety legislation. At the same time, the size of such bags presents theft opportunities and annual operating profits are frequently affected by such action. Use of bulk packaging (bags typically in excess of 100 kg) is known in industry but this presents increased residual waste problems for viscous materials because bulk packages such as 1,000 litre in-liners are unable to be emptied by twin roller wringers in a practical and health and safety approved manner. Attempts have been made to provide cylindrical vessels with piston based emptying systems but these have proven to be far too complex and expensive for the intended applications. The problem is particularly acute in the plaster industry due to the viscous and adherent nature of the in-liner contents.

According to a first aspect of the present invention, there is provided apparatus for pressurising the contents of a bag, being a bulk package such as an in-liner, comprising a bag having a first end and a second end opposite thereto, a bag engaging element adapted to engage with the said first end of the bag for mutual rotation therewith, actuating means operable to drive the bag engaging element about an axis of rotation which extends through the bag between the said first and second ends thereof so that the engaging element rotates the said first end of the bag about the said axis in a drive direction and optional stabilising means to effectively maintain at least a part of the second end of the bag in a substantially stationary position during rotation of the said first end thereof.

Suitably, the bulk package has an internal volume of greater than or equal to 5 litres (1) , preferably greater than or equal to 20 1, more preferably greater than or equal to 50 1, even more preferably greater than or equal to 100 1, even more preferably greater than or equal to 500 1, especially approximately 1000 1. Preferably the bulk package is an in-liner, especially an in-liner having the aforementioned internal volume.

By the term in-liner, we mean a bulk package that is suitable for storing and transporting viscous materials, such as plaster or paint, which may be loaded into a dosing container.

Advantageously, rotation of the said first end effectively reduces the available volume in the said bag by spiralling the first end of the bag and thereby increases the internal bag pressure acting on the bag contents.

As the first end rotates into a spiral, a counter rotational torsional force will gradually develop in the spiral.

Preferably, the actuating means is operable to switch into a non-drive mode above a pre-determined threshold bag counter rotational force and to switch back into a rotating mode (drive mode) below a pre-determined bag counter rotational force. Suitably, the actuating means includes a resistance to inhibit rotation of the engaging element with respect to the actuating means in a counter-drive direction, particularly when the actuating means is in the non-drive mode .

Conveniently, when the actuating means is in the non-drive mode, unrestricted rotation of the engaging element with respect to the actuating means in the counter-drive direction is inhibited by the resistance thereby essentially maintaining the internal bag pressure acting on the contents of the bag. Suitably, the contents progressively empty from the bag, thereby causing a progressive decrease in the internal bag pressure and/or permitting the spiral to unwind partially. Suitably, when the counter rotational force exerted by the bag is below the predetermined threshold value, then the actuating means switches back into the drive mode. The bag is further wound into a spiral thereby increasing the internal bag pressure. When the predetermined threshold bag counter rotational force is attained, then the actuating means switches into the non-drive mode.

It will be appreciated the contents may be emptied from the bag when the actuating means is in the drive and/or non-drive mode. Conveniently, such a process permits a controlled and progressive emptying of the contents from the bag, thereby minimising residual material in the bag.

Suitably, the resistance of the actuating means exerts a force in an opposite direction to the bag counter rotational torsional force. Suitably, the force exerted by the resistance is greater than or equal to 95% of the predetermined threshold bag counter rotational force, preferably greater than or equal to 97%, even more preferably greater than or equal to 98%, especially essentially equal to the predetermined threshold bag counter rotational force.

It will be appreciated that when the force exerted by the resistance is 95% of the predetermined threshold bag counter rotational force, then the engaging element may rotate to a certain extent with respect to the actuating means in the counter-drive direction to allow the internal bag pressure to decrease by up to 5%.

Most preferably, the force exerted by the resistance is essentially equal and opposite to the predetermined threshold bag counter rotation force, such that the engaging element is essentially static with respect to the actuating means when the actuating means is in the non- drive mode .

Suitably, the resistance of the actuating means comprises a gearing mechanism, especially a worm gear.

The bag counter rotational force may be determined by determining the counter rotational force acting on the engaging element .

The actuating means may include a motor or other motive power source to provide motive power for rotational motion of the engaging element. Preferably, the actuating means also includes a driving element. Preferably, the bag engaging element is mounted on or otherwise connected to the said driving element, such as a drive shaft, to thereby provide the communication with the motive power source. The driving element is typically connected at one end to the motive power source and at the opposite end to the engaging element.

Preferably, the driving element is connected to the motive power source by a gearing mechanism. Conveniently, the gearing mechanism forms the resistance to inhibit rotation of the engaging element with respect to the actuating means in the counter-drive direction, when the actuating means is in the non-drive mode. A highly preferred gearing mechanism comprises a worm gear.

Preferably, in order to respond to the internal bag pressure, a counter rotational force actuated cut-off switch is connected to the apparatus. Preferably, the untwisting force exerted by the bag spiral provides a counter rotational force which actuates the cut-off switch above a certain torsional force and reactivates the apparatus below a certain torsional force.

Preferably, the apparatus includes a drive cut-off assembly operable for deactivating the actuating means into a non-drive mode when the counter rotational force exerted by the bag is above a predetermined threshold value, wherein the drive cut-off assembly is rotatable with respect to said axis of rotation. Preferably, the drive cut-off assembly is rotatable about the axis of rotation.

Preferably, the drive cut-off assembly is operable for activating the actuating means from the non-drive mode to the drive mode when the counter rotational force exerted by the bag is below a predetermined threshold value.

Preferably, the drive cut-off assembly is operable to rotate with respect to said axis of rotation in the counter-drive direction when the counter rotational force exerted by the bag is above a predetermined threshold value, thereby deactivating the actuating means into the non-drive mode.

Preferably, the drive cut-off assembly includes a counter- drive resistant member to inhibit rotation of the drive cut-off assembly with respect to said axis of rotation in the counter-drive direction.

Preferably, the drive cut-off assembly is operable to rotate with respect to said axis of rotation in the drive direction when the counter rotational force exerted by the bag is below a predetermined threshold value, thereby activating the actuating means into the drive mode.

Preferably, the drive cut-off assembly includes a lock member to inhibit rotation of the drive cut-off assembly with respect to said axis of rotation in the drive direction.

Preferably, the actuating means includes a resistance as described herein to inhibit rotation of the engaging element with respect to the actuating means in the counter-drive direction.

Preferably, the drive cut-off assembly includes a cut-off switch responsive to the rotational movement of the cut- off assembly, thereby activating or deactivating the actuating means.

Preferably, the drive cut-off assembly includes the actuating means.

In a highly preferred embodiment, the drive cut-off assembly includes the actuating means and the actuating means includes a resistance to inhibit counter-drive rotation of the engagement element with respect to the actuating means. Conveniently, when the counter-rotational force exerted by the bag is above a predetermined threshold level, the counter-rotation force is transmitted from the engagement element to the actuating means. Suitably, the actuating means and the engagement element rotate in a counter-drive direction, thereby deactivating the actuating means into the non-drive mode.

Suitably, when the counter-rotational force decreases below the predetermined threshold level due to the contents emptying from the bag, the actuating means and the engagement element rotate in the drive direction, thereby activating the actuating means into the drive mode .

Preferably, a drive cut-off assembly is mounted so that it is itself rotatable about the said axis of rotation. Preferably, the cut-off assembly rotation in the direction of drive rotation about the axis is inhibited, preferably, by a lock mechanism. Preferably, the lock mechanism is a suitable abutment means for at least a part of the assembly to thereby prevent rotation. Accordingly, the cut-off assembly is, itself, preferably, rotatable in the direction about the said axis opposite the drive direction. Preferably, the cut-off assembly is urged against such counter-drive rotation by engaging with a counter-drive resistant member. Preferably, the said resistant member is operable above a pre-determined counter-drive rotational force to allow counter-drive rotation of the cut-off assembly. Preferably, said counter-drive rotation actuates the cut-off switch for the actuating means or otherwise disengages drive from the engaging element to prevent rotational motive force being supplied to the engagement element. Preferably, the resistant member is operable below a predetermined counter-drive rotational force to force the cut-off assembly to rotate back in the drive direction. Preferably, such rotation deactivates the cut-off switch. The cut-off assembly is, preferably, connected directly or indirectly to the rotational axis of the apparatus and, preferably, comprises a pivotable arm connected to the resistant member. Preferably, the resistant member is a resiliently deformable member. The resiliently deformable member is operable to deform under a predetermined force to allow or cause the cut off assembly to pivot, the pivoting of the cut-off assembly causing the movement necessary for the arm to actuate the cut-off switch. The cut-off assembly may be mounted on the rotational axis, either directly or indirectly via, for instance, an element upon which it is mounted. Preferably, the actuating means is rotatable about the axis of rotation in a counter-drive direction.

Preferably, the apparatus includes a supporting structure for attaching the various features of the invention. Preferably, the actuating means is mounted on or depends from the supporting structure.

Preferably, the actuating means is mounted/depends in such a way as to prevent movement of the engaging element along the axis of rotation during use and to maintain the axis of rotation in a fixed position with respect to the bag.

In one embodiment, the supporting structure is in the form of a plate-like member with a motor mounted thereon via the drive shaft of the motor extending therethrough along the said axis of rotation.

The engaging element may be mounted on the bag proximal end of the drive shaft for rotational motion of said first end of the bag about the rotational axis of the drive shaft. Preferably, the cut-off assembly is mounted for counter-drive rotation with the engaging element, preferably about the axis of rotation. A pivotable arm may be directly or indirectly fixed to the engaging element and be connected at one end to one end of a tension spring. The tension spring may have its other end fixed in position, preferably by mounting it directly or indirectly upon the supporting structure. The tension spring is preferably arranged to resist rotation of the pivotable arm, in the direction of counter-drive rotation. Preferably, rotational movement of the pivotable arm in the said drive direction is also prevented by a suitable lock member acting on the pivotable arm. Rotational movement of the pivotable arm in a counter-drive direction is preferably prevented by the tension in the fixed spring until a predetermined torsional force is reached which is greater than the tension in the spring and the pivotable arm is then rotated on its axis. Preferably, movement of the pivotable arm in the counter-drive direction causes one end of the pivotable arm to trigger a suitable cut-off switch to cut power to the engaging element. As soon as the rotational force falls below the predetermined level, the tension spring urges the pivotable arm back into its original position thereby de-activating the cut-off switch and re-activating the engaging element. This process repeats automatically to maintain the torsion in the bag spiral and hence the internal pressure in the bag.

In one embodiment, the motor and drive shaft are both mounted below the support structure and the spring and pivotable arm are mounted above the support structure. Preferably, the pivotable arm is mounted on the bag distal end of an auxiliary shaft which extends through the support structure and is connected to the actuating means at its proximal end in such a way that it is not acted upon by the drive shaft. Again, rotation of the pivotable arm about the auxiliary shaft axis in a drive direction is prevented by a lock member which abuts against the pivotable arm whereas rotation in the counter-drive direction is possible only when a predetermined torsional force is reached to overcome the force of the tension spring attached to a first end of the pivotable arm. The second end of the pivotable arm is operable to activate a cut-off switch in response to such movement and to deactivate the cut-off switch when rotated back under the force of the spring.

It will be clear from the foregoing that a compression spring or other deformable device with a predetermined load for activation can also be utilised as the resistant member for the same purpose .

In the foregoing it should be stated that it is particularly advantageous to mount the motor or other actuating means and hence the drive shaft in such a manner that counter-drive rotation of the engaging element is initially possible whilst the drive is still being driven by the actuating means . This maintains the torsion in the bag spiral until the cut-off switch is activated.

Preferably, the engaging element is rotatable in a counter-drive direction above a pre-determined torsional force in the bag and preferably, such counter-drive rotation actuates a drive cut-off mechanism to prevent further rotation in the drive direction.

According to a second aspect of the present invention there is provided apparatus for pressurising the contents of a bag such as a bulk packaging in-liner comprising a bag engaging element adapted to engage a first end of a bag for mutual rotation therewith, actuating means operable to drive the bag engaging element about an axis of rotation which also extends, in use, through the bag so that the engaging element rotates a bag into a spiral about the said axis from the engaging element end of a bag and optional stabilising means to effectively maintain at least a part of a second end of a bag in a substantially stationary position during rotation of the said first end thereof wherein, in use, the engaging element is rotatable in a counter-drive direction above a pre-determined torsional force and wherein such counter-drive rotation actuates a drive cut-off mechanism to prevent further rotation in the drive direction.

Preferably, the bag is an in-liner. Preferably, an in- liner is a bag for a container such as a drum.

Preferably, the support structure is designed to act as the lid of such a container.

Preferably, the viscosity of material in the bag is in the range 1 x 10^"4 to 1 - 400 Pas, more preferably, 10 to 200 Pas, most preferably to 80-120 Pas.

According to a third aspect of the present invention there is provided a method of emptying a bag, being a bulk package such as an in-liner, the method comprising the steps of : -

attaching one end of the bag to a bag engaging element of an apparatus in accordance with any of the earlier aspects of the present invention and actuating the bag engagement element to spiral the first end of the bag about its axis and thereby increase internal bag pressure to thereby effectively squeeze out the contents of the bag, optionally via an outlet at the opposite end thereof.

Preferably, the process of bag emptying is interrupted upon attainment of a counter-drive torsional force in the bag spiral in excess of a predetermined torsional force and is reactivated upon the torsional force falling below a predetermined level . Preferably, the initial loaded bag weight is in excess of 25 kg, more preferably in excess of 50 kg, most preferably in excess of 100 kg, especially 500 kg. Typically, the initial loaded bag weight is between 25 kg and 8000 kg, more preferably between 100 kg and 4000 kg, most preferably between 1000 kg and 3000 kg.

However, for micro-applications, the loaded bag weight may be less than 25 kg, preferably, less than 10 kg and, alternatively, less than 1 kg.

Typically, the bag includes an outlet at the second end, opposite to the first end which is connected to the bag engaging element, and the outlet preferably co-operates with a dosing device connected to the said outlet. In an alternative embodiment, the bag may be porous so that the bag may be used to squeeze out liquid from the contents, via the pores, from the bag to a predetermined pressure level matching that of the counter-drive torsional force applied by the spiral. In such an embodiment, it would be apparent that an outlet for the bag may not be necessary. For instance, such a bag could be used for the production of yoghurt .

The apparatus and method have particular advantages in the dosing of viscous fluid materials which are otherwise difficult to handle; especially viscous fluid materials which may adhere to the inside of a bag, and be sufficiently viscous and/or adherent, as to remain in place when the bag is merely suspended.

In accordance with the invention, as the bag is progressively emptied, the bag lining effectively forms into a spiral. It has been found that this technique is particularly effective in minimising residual material remaining in the bag.

Typically, when the bag is an in-liner it is located in a metal container with an outlet at the bottom to which the in-liner outlet is connected. The outlet is typically connected to application equipment for pumping or otherwise directing the bag contents towards their end use. The bags in accordance with the invention typically include a suitable portion of surplus bag material at the upper end thereof . The surplus material may be connected to the engaging element which may suitably be in the form of a hook or clamp. Typically, a modified lid (or a diametric cross-member) of a metal container is used for the support structure for mounting the apparatus of the invention and the rotational axis about which the engaging element rotates is located centrally with respect to the lid and extends at right angles thereto. After attaching the surplus material at the upper end of the in-liner to the engaging element, the engaging element is rotated about the rotational axis and forms the surplus material into a spiral which puts pressure on to the bag contents until a pre-determined counter rotational force is reached at which point the cut-off assembly is actuated and the drive is deactivated. Typically, as sufficient fluid is pumped out of the in-liner, the tension in the in-liner spiral reduces causing the drive to be re-actuated until sufficient counter-drive tension in the spiral is built up again. This process is repeated until the in-liner is completely spiralled and emptied. After emptying, the rotating direction of the motor may be reversed and the emptied in-liner is removed from the engaging element. The modified lid may then be placed on a new container and the process repeated.

As mentioned above, the bag may include an outlet at the end opposite the end secured to the engagement means. Preferably, the outlet is designed to co-operate with the outlet to the container for the passage of material therethrough and is most preferably close fitting therewith in such a manner as to securely fix the outlet in position to prevent rotation thereof during bag spiralling. Accordingly, the outlet may act as the anchor for the spiral as the bag empties and the inertia of the bag can no longer prevent rotation of the filled part of the bag. The outlet may co-operate with a delivery line for transmission of the material for an end use application. For instance, the bag may co-operate with a hose inlet for the delivery of material therethrough. In one embodiment, the hose inlet and the bag outlet cooperate in a clamp-like manner which securely clamps them to the base of the container.

Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings in which: -

Figure 1 shows a side view of an apparatus in accordance with the present invention in contact with an in-liner; Figure 2a shows a plan view of the apparatus of figure 1; Figure 2b shows a sectional view of the apparatus of figure 1; and

Figure 3 shows an alternative embodiment of the engagement element; Figure 4 shows an alternative apparatus in accordance with the present invention;

Figure 5 shows a plan view of the apparatus of figure 4; Figure 6 shows a bag outlet in accordance with the present invention;

Figure 7 shows a bag in contact with the apparatus of figure 4; and

Figure 8 shows a spiralled bag in contact with the apparatus of figure 4.

Referring to figures 1 and 2, a cylindrical container 2 has an in-liner bag 20 containing a highly viscous fluid, a lid 7 at the top thereof and a centrally disposed outlet hole 3 at the bottom thereof. Located in the container is a bulk in-liner bag which has an outlet 1 at the bottom thereof designed to be close fitting with the outlet 3 of the container 2. The upper part 9 of the bag 20 is empty and is shown in the process of being spirally wound by the engaging element 22. The engaging element comprises a twin armed anchor section 5 and a drive shaft 24 extending upwardly from the mid point of the two arms of the anchor and which is journalled in a motor 28 which will be more particularly described hereafter. The drive shaft 24 extends upwardly through a centrally disposed hole 26 in the lid 7. The engaging element therefore extends downwardly from the under side of the lid into the interior space of the container 2. At the bag proximal end of the vertical drive shaft 24, the anchor section 5 comprises a pair of opposed angled hooking arms 13, 15 extending generally outwardly therefrom. The matching hooking arms extend at approximately 30° with respect to a theoretical horizontal plane co-planar with the proximal end of the shaft 24 and then angle through approximately 60° to extend perpendicularly and part way towards the lid. The hooks provide a tie point for the bag surplus material 30 which forms the top of the bag. The surplus material is secured to the anchor 5 by a suitable knot and rotation of the drive shaft causes the upper end of the bag to spiral whilst the filled part of the bag remains stationary thus eventually urging the contents of the bag to the outlet 1 at the bottom end thereof .

Referring more specifically to figures 2a and 2b, the distal end of the drive shaft 24 passes through the centrally disposed hole 26 in the lid 7 and is journalled in a motor 28 which is mounted on top of the lid 7 by means of an interposed shaft collar 32 which is itself mounted on the lid surface and positioned between the motor and the lid surface. The drive shaft 24 is journalled to the motor 28 by a worm gear mechanism (not shown) . The worm gear mechanism inhibits rotation of the drive shaft 24 with respect to the motor 28 in the counter-drive direction. Accordingly, although the motor is secured in position above the lid, the motor and drive shaft combination are rotatable about the rotational axis in the drive and counter-drive direction. A bent pivotable arm 34 is fixed at its proximal end 35 to the motor housing and at its distal end 37 to one end 41 of a tension spring 40 extending perpendicularly away from the distal end of the pivotable arm and which spring is itself secured at its other end 43 to the lid surface. Located adjacent to the tension spring 40 towards the proximal end of the arm 34 is a stopper 42, with an in-built cut-off switch, which engages with the inner side 45 of the bent pivotable arm, in use, so that the motor is continued to be supplied with power. The stopper 42 abuts the pivotable arm 34 to prevent rotation of the motor in the drive direction. As rotation of the spiral continues, the counter-drive rotational force is transmitted from the drive shaft 24 to the motor 28 and the pivotable arm 34. A point is reached at which the counter-drive torsional force in the spiral overcomes the tension in the spring 40 causing rotation of the motor and bent arm in a counter- drive direction and causing the spring loaded switch head 44 to be released thereby cutting power to the motor 28. At this point, the spiral of the bag is maintained in a relatively constant position by the worm gear mechanism of the motor, thus squeezing the material towards the outlet 1 of the in-liner in a controlled manner. However, as material is pumped out of the in-liner, the torsional force in the spiral gradually reduces, eventually causing the tension spring 40 to urge the arm 34 back into position to depress the switch head 44 and restore power to the motor. In this way, the torsional force in the spiral is increased again and the process is repeated. This occurs successively until the bag is completely emptied of material and the bag is completely spiralled.

Referring to figure 3, an alternative hook embodiment of the anchor is shown. As previously described, the drive shaft 48 has an anchor comprising two opposed matching arms in the form of two opposing hooks 50', 52 at the proximal end thereof. However, in this arrangement, the hooks do not consist of angled arms but extend from the proximal end of the drive shaft 48 in opposite directions and in an arcuate manner towards the lid (not shown) , until they have each described an angle of approximately 90°, and then extend perpendicularly part way towards the lid as before. The tie line 54 is shown passed around the end of the drive shaft 48 and held in place, via a suitable knot, by the anchor.

After use, the tie-line may be released and the lid mechanism located on a fresh container so that the process can be repeated.

Referring to figures 4 and 5, an alternative drive mechanism for the invention is shown. The embodiment includes a clamp member 100 which comprises a pair of opposing spaced parallel elongate fixed plates 102, 104 which are held apart by a pair of opposing spaced parallel rods 106, 108 extending perpendicularly between the end portions of the plates and each fixed at their respective ends to the said end portions of the plates . A third moveable plate 110 is located on the bottom plate 104 in superposed relationship therewith and has a rod hole (not shown) at either end thereof which is positioned and sized to co-operate with the respective rod 106, 108 for sliding engagement therewith between the two spaced plates 102 and plate 104. The clamp member engagement means may be interchanged with, for instance, the hooked anchor as described with reference to figure 3 to provide a further alternative embodiment to that described herein with reference to figures 4-8.

A connecting web 112 extends perpendicularly from the upper surface of the top plate 102 which is rigidly attached to a drive shaft 114 via a linking bracket 115, coupled to the connecting web via a nut and bolt 117 and to the drive shaft via a longitudinal slot in the proximal end of the drive shaft into which the bracket 115 partially extends. The drive shaft is journalled in and driven by a motor 116 in a manner as previously described. The axis of the drive shaft 114 extends perpendicularly with respect to the plane of the lid 130 so that a theoretical axis in the centre of the drive shaft would pass perpendicularly through the centre of the lid.

The motor 116 has a pair of spaced fixing brackets 118, 120 on the upper and lower side thereof. The brackets extend horizontally from the upper and lower side of the motor in the same direction. The base of each of the brackets 118 and 120 is bolted to a vertical arm 122 of a further L shaped bracket 124 on one side and spaced from the motor. The L shaped bracket has a horizontal arm 126 extending from the uppermost end of the vertical arm 122 and back towards the axis of the motor 116. However, the bottom surface of the horizontal arm 126 is spaced from the upper surface of the motor 116 assembly so that the only connection between the motor and the upper arm 126 is via the connection on the vertical arm of the L shaped bracket 124.

An upper auxiliary shaft 128 co-axial with the drive shaft 114 extends upwardly from the upper surface of the horizontal arm 126 and extends through a suitably sized and centrally disposed hole 132 in the lid 130. The shaft 128 includes a collar 134 which is itself fixed in a mounting 136 found on the lower surface of the lid. The distal end of the shaft 128 is welded to the underside of a pivotable arm 140 midway between the ends thereof. The pivotable arm 140 is in the form of an elongate thin plate which is secured at a first end 142 to the proximal end 144 of a tension spring 146. The tension spring is of a plain spiral construction, and is fixed at the end opposite the pivotable arm to a boss 149 projecting from the lid. The shaft 128 has the ability to rotate on its axis but is generally prevented from counter-drive rotation by the tension in the spring 146. However, if sufficient rotational force is applied to the shaft 128 via the counter-drive rotational force of the spiralling bag, then the pivotable arm can pivot about the auxiliary shaft axis.

The opposite end 152 of the pivotable arm 140 to the end attached to the tension spring 146 is able to describe an arc from the stopper 148 and cut off switch 150 in a clockwise direction. When the counter rotational tension in the bag being twisted is below a certain threshold level, the end 152 of the arm rests against the stopper 148 which prevents the arm 140 and hence the auxiliary axis and motor from rotating. However, when sufficient counter rotational torsional force is built up in the bag spiral, the tension in the tension spring 146 is overcome causing the pivotable arm to pivot about the axis of the shaft 128 and causing the end opposite the spring attached end to describe the aforesaid arc until it is urged into contact with the cut off switch 150 thereby cutting power to the motor 116. This allows the torsional force in the bag spiral to be held at a predetermined level . As contents of the bag are pumped through the outlet of the container, the torsional force in the bag spiral will progressively fall until the tension in the tension spring 146 is again able to pivot the pivotable arm in the opposite direction until it abuts against the stopper 148. Referring to figure 6, a suitable outlet arrangement for the bag at the base of the container is shown in partial section. A threaded ring hose 160 includes a flexible hose wall 162 leading to a corresponding terminal hose ring 164. The terminal hose ring 164 includes an annular abutment flange 166 extending outwardly therefrom and an externally threaded section 168 which forms the leading end of the hose ring. The bag wall 170 terminates in an outlet opening 172 and the outlet ends of the bag are fixed into a circumferential slot 176 formed in the inner surface of an abutment flange 178 of an internally threaded ring member 174 which forms the outlet ring of the bag. The leading end 180 of the outlet ring is internally threaded for threaded engagement with the leading end 168 of the exteriorly threaded ring hose. The circumferential slot 176 is formed in the inner face of the interior annular abutment flange 178 which forms the main body of the ring member and is located behind the threaded leading end. The exterior surface 183 of the leading end of the ring 180 is smooth and designed to be close fitting with wall of the outlet 182 in the container bottom wall 184. The depths of the interiorly threaded leading end of the ring 180 and the leading end of the exteriorly threaded ring hose 168 are designed so that when the threaded ring hose is fully screwed in position, the threaded ring flange 178 and the threaded ring hose flange 166 tightly abut against either side of the container bottom to clamp against it and provide a tight fit therewith. This arrangement prevents rotation of the outlet of the bag in use. The leading end of the threaded ring hose has a coring wire 185 with two arms 191, 193 extending forwardly therefrom and extending inwards from opposite sides of the ring to meet and terminate at a point 195 which coincides with the axis of the hose. Prior to use, the bag includes a safety seal 190 which covers the ring outlet 172 to prevent escape of viscous material. However, during screwing of the threaded ring hose into position the leading end 195 of the coring wire 185 breaches the safety seal 190 to cut or tear away the safety seal as the threaded ring hose is progressively screwed into engagement with the threaded ring outlet. Accordingly, after the ring hose has been secured in position, the safety seal has been removed and the base of the bag has been securely fixed in position to resist the rotational force applied to the base of the bag which increases as the bag empties.

In an alternative embodiment to that shown in figure 6, the threaded co-engagement of the hose and outlet may be replaced with a push or snap-fit assembly. In such an embodiment the leading end of the hose ring may include circumferential serrations projecting outwardly therefrom to cut through the safety seal 190. In a preferred version of such an embodiment, a section of the circumference of the leading end of the hose ring is unserrated so that the safety seal is not completely cut away by the serrations but opens to allow passage of material through the outlet whilst remaining attached to the bag outlet. The seal is thereby prevented from passing through the hose and into the dosing equipment.

Referring now to figure 7, a bag 210 similar to that previously described with respect to figure 1 is shown located in a container 212 having its lower end secured to an outlet 214 and its upper end in the process of being clamped by an engaging element 216 of the type previously described with respect to figure 4. In the arrangement shown, the upper end of the bag includes some surplus material which may be gathered together and passed over the slideable clamp 218 before being passed back through a gap formed between the slideable clamp 218 and the fixed lower clamp 220. A knot may then be tied in the end of the bag to prevent the bag material coming free of the clamp. In use, as the clamp rotates the bag spirals from the upper end and gradually applies pressure to the bag contents. At the same time the bag will tighten and pull the clamp closed on itself to further secure it in the clamp. Eventually, the bag is fully spiralled as depicted in figure 8 and the contents are fully removed. The outlet may then be unscrewed and the spiral 230 removed so that the clamp assembly may be reused.

The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings) , and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment (s) . The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings) , or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

1. An apparatus for pressurising the contents of a bag, being a bulk package, comprising a bag having a first end and a second end opposite thereto, a bag engaging element adapted to engage with the said first end of the bag for mutual rotation therewith, actuating means operable to drive the bag engaging element about an axis of rotation which extends through the bag between the said first and second ends thereof so that the engaging element rotates the said first end of the bag about the said axis in a drive direction and optional stabilising means to effectively maintain at least a part of the second end of the bag in a substantially stationary position during rotation of the said first end thereof.

2. An apparatus as claimed in claim 1 wherein the bag comprises an in-liner.

3. An apparatus as claimed in claim 1 or 2 wherein the actuating means is operable to switch into a non-drive mode when the counter rotational force exerted by the bag is above a threshold value.

4. An apparatus as claimed in claim 3 wherein the actuating means includes a resistance to inhibit rotation of the engaging element with respect to the actuating means in the counter-drive direction.

5. An apparatus as claimed in claims 3 or 4 wherein the actuating means is operable to switch from the non-drive mode to the drive mode when the counter rotational force exerted by the bag is below a threshold value.

6. An apparatus as claimed in any one of the preceding claims wherein the apparatus includes a cut-off switch responsive to the bag counter rotational force for switching the actuating means into a non-drive mode when the counter rotational force exerted by the bag is above a threshold value.

7. An apparatus as claimed in claim 6 wherein the cut-off switch is operable for switching the actuating means from the non-drive mode to a drive mode when the counter rotational force exerted by the bag is below a threshold value.

8. An apparatus as claimed in claim 6 or 7 wherein the cut-off switch comprises an actuated cut-off switch.

9. An apparatus as claimed in any one of the preceding claims wherein the apparatus includes a drive cut-off assembly operable for deactivating the actuating means into a non-drive mode when the counter rotational force exerted by the bag is above a threshold value, wherein the drive cut-off assembly is rotatable with respect to said axis of rotation.

10. An apparatus as claimed in claim 9 wherein the drive cut-off assembly is operable for activating the actuating means from the non-drive mode to the drive mode when the counter rotational force exerted by the bag is below a threshold value.

11. An apparatus as claimed in claims 9 or 10 wherein the drive cut-off assembly is operable to rotate with respect to said axis of rotation in the counter-drive direction when the counter rotational force exerted by the bag is above a threshold value, thereby deactivating the actuating means into the non-drive mode.

12. An apparatus as claimed in claim 11 wherein the drive cut-off assembly includes a counter-drive resistant member to inhibit rotation of the drive cut-off assembly with respect to said axis of rotation in the counter-drive direction.

13. An apparatus as claimed in any one of claims 9 to 12 wherein the drive cut-off assembly is operable to rotate with respect to said axis of rotation in the drive direction when the counter rotational force exerted by the bag is below a threshold value, thereby activating the actuating means into the drive mode.

14. An apparatus as claimed in claim 13 wherein the drive cut-off assembly includes a lock member to inhibit rotation of the drive cut-off assembly with respect to said axis of rotation in the drive direction.

15. An apparatus as claim in any one of claims 9 to 14 wherein the actuating means includes a resistance to inhibit rotation of the engaging element with respect to the actuating means in the counter-drive direction.

16. An apparatus as claimed in any one of claims 9 to 15 wherein the cut-off assembly includes a cut-off switch for activating or deactivating the actuating means, wherein the cut-off switch is responsive to the rotational movement of the drive cut-off assembly.

17. An apparatus as claimed in any one of claims 9 to 16 wherein the drive cut-off assembly includes the actuating means .

18. An apparatus as claimed in any one of the preceding claims wherein the actuating means is mounted on or depends from a supporting structure.

19. An apparatus as claimed in any one of claims 9 to 17 wherein the actuating means and the drive cut-off assembly are mounted on a supporting structure.

20. An apparatus as claimed in any one of claims 9 to 17 wherein the actuating means depends from a supporting structure and the drive cut-off assembly is mounted on the supporting structure.

21. An apparatus as claimed in claim 19 or 20 wherein the bag engagement element depends from the supporting structure .

22. An apparatus as claimed in any one of claims 9 to 21 wherein the bag engaging element is rotatable in a counter-drive direction about said axis of rotation when the bag counter rotational force is above a threshold value thereby operating the drive cut-off assembly.

23. An apparatus as claimed in any one of claims 9 to 22 wherein the actuating means is rotatable in a counter- drive direction about said axis of rotation when the bag counter-rotational force is above a threshold value thereby operating the drive cut-off assembly.

24. Apparatus for pressurising the contents of a bag such as a bulk packaging in-liner comprising a bag engaging element adapted to engage a first end of a bag for mutual rotation therewith, actuating means operable to drive the bag engaging element about an axis of rotation which also extends, in use, through the bag so that the engaging element rotates a bag into a spiral about the said axis from the engaging element end of a bag and optional stabilising means to effectively maintain at least a part of a second end of a bag in a substantially stationary position during rotation of the said first end thereof wherein, in use, the engaging element is rotatable in a counter-drive direction above a pre-determined torsional force and wherein such counter-drive rotation actuates a drive cut-off mechanism to prevent further rotation in the drive direction.

25. A method of emptying a bag, being a bulk package such as an in-liner, the method comprising the steps of providing apparatus for pressuring the contents of a bag as defined in any one of claims 1 to 24, attaching the bag to the bag engaging element, actuating the bag engagement element to spiral the first end of the bag about its axis and thereby increase internal bag pressure to thereby effectively squeeze out the contents of the bag, optionally via an outlet at the opposite end thereof.

26. A method as claimed in claim 25 wherein the process of actuating the bag engagement element is interrupted upon attainment of a counter-drive torsional force in the bag spiral in excess of a predetermined torsional force and the bag engagement element is reactivated upon the torsional force falling below a predetermined level.

27. A method according to claim 25 or 26 wherein the bag has an initial loaded weight in excess of 25 kg.

28. A method according to any one of claims 25 to 27 wherein the bag includes an outlet at a second end opposite to a first said end which is connected to the bag engaging element .

29. A method as claimed in any one of claims 25 to 27 wherein the bag is porous such that at least part of the contents of the bag are squeezed out via the pores.

30. A method as claimed in claims 25 to 28 further including the step of connecting the outlet of the bag to an applicator.