WO2003080446A1

WO2003080446A1 - Materials handling equipment

Info

Publication number: WO2003080446A1
Application number: PCT/GB2003/000856
Authority: WO
Inventors: Barrie Armstrong Poulton
Original assignee: Fairport Engineering Group Limited
Priority date: 2002-03-22
Filing date: 2003-02-27
Publication date: 2003-10-02
Also published as: GB0206775D0; AU2003215728A1

Abstract

A machine for discharging an intermediate bulk container comprises a hopper-like receptacle (10) for the bottom of a container (c), a door (11) in the wall of the hopper-like receptacle to give access to the spout of the container to permit tying and untying thereof, and a device for constricting the spout of the container located within the hopper-like receptacle. The device comprises a rigid mount (12) having a circular aperture (13) therein through which the spout may be located. A circular ring (15) surrounds the aperture (13) and a number of cables (20) extend from the rigid mount (12) at spaced locations around the circular aperture to the circular ring (15) at spaced locations around its circumference. A drive arrangement (30) is provided to rotate the ring (15) relative to the rigid mount to cause the cables (20) to move from a first position generally following the periphery of the aperture to a second position in which they cross one another to form a restricted opening capable of constricting the spout of the container.

Description

APPARATUS FOR DICHARGING A BULK CONTAINER

This invention concerns materials handling equipment, and more particularly equipment for discharging particulate solid materials from intermediate bulk containers comprising a flexible bag - which may or may not have an inner lining - and having a normally tied tubular spout through which discharge can be effected after the spout has been untied. Such containers (hereinafter terms containers of the kind referred to) are commonly known as "big bags".

Containers of the kind referred to are normally discharged using a special discharging machine including means to support the bag over a generally hopper-like receptacle for the bottom of the bag and having a door giving access to the spout to permit untying thereof.

It is sometimes desired to discharge less than the full contents of the bag and various arrangements are known to constrict the spout to permit retying of the spout prior to removal of the bag from the machine.

One such arrangement is described in our patent number GB 2250016 wherein loops of flexible cable are drawn together around the spout. The cables pass through apertures in the walls of the hopper to connect with operating mechanism thus preventing total containment of material within the hopper which is unacceptable for certain materials such as pharmaceuticals.

It is an object of the present invention to provide a discharging machine for containers of the kind referred to having means to constrict the spout of a container using cables (which can be flexible so as to conform to the contours of the base of the container) without the problem aforesaid.

According to the present invention there is provided a machine for discharging a container of the kind referred to comprising a hopper-like receptacle for the bottom of a container, a door in the wall of the hopper-like receptacle to give access to the spout of the container to permit tying and untying thereof, and means for constricting the spout of the container located within the hopper-like receptacle and comprising:

(a) a rigid mount having a circular aperture therein through which the spout may be located;

(b) a circular ring surrounding said aperture;

(c) a number of cables extending from the rigid mount at spaced locations around the circular aperture to the circular ring at spaced locations around its circumference; and (d) means for rotating the ring relative to the rigid mount to cause the cables to move from a first position generally following the periphery of the aperture to a second position wherein they cross one another to form a restricted opening capable of constricting the spout of the container.

There may for example be three flexible cables whose ends are angularly spaced by 120°.

The invention will be further apparent from the following description with reference to the several figures of the accompanying drawings, which show, by way of example only, one form of discharging machine embodying same. In the drawings: Figure 1 hows a front elevation of the discharging machine; Figure 2 shows a plan view from below of spout constricting means located within the hopper and in a fully open position; Figure 3 hows a cross-section through the constricting means on the line III- III of Figure 2; and

Figures 4 & 5 how plan views from below of the constricting means in a partially closed and fully closed positions respectively.

Referring now to the drawings, it will be seen that the discharging machine comprises a shallow hopper 10 to locate the bottom of a container of the kind referred to

C with its spout S hanging downwardly through the hopper. A door 11 in a front wall of the hopper can be opened to give access to the spout to permit tying and untying thereof.

Within the hopper 10 is a spout constricting arrangement comprising a rigid mount 12 secured to the walls of the hopper 10 and having a circular aperture 13 through which the spout S is passed.

The rigid mount 12 presents an outwardly directed channel 14 surrounding the aperture 13 which locates a circular ring 15 seated on a wear strip 16 of plastic material.

Three pins 17 extend downwardly from the underside of the channel 14 angularly spaced from one another by 120°. Three further pins 18 extend downwardly from the underside of the ring 15 angularly spaced from one another by 120°.

Three lengths of flexible cable 20 extend between the pins 17 and 18, each extending clockwise (as seen in Figure 2) from a pin 17 to the nearest pin 18 when the pins 17 and 18 are arranged in adjacent pairs (see Figure 2). When the device is in the fully open position, the ends of each cable are spaced angularly by about 120°. A pneumatically powered piston and cylinder actuator 30 having a linearly movable piston rod can be operated to rotate the ring 15 relative to the mount to cause the cables 20 to move from a fully open position (Figure 2) to a fully closed position (Figure 5) constricting the spout S to arrest flow of material therethrough enabling the spout S to the tied and a partially emptied container removed without significant loss of any material. As the device is operated, the cables cross one another to an increasing extent thereby effecting greater constriction of the spout.

The piston rod and the ring may be provided with meshing gear teeth to translate linear motion of the piston into rotation of the ring as the piston rod is extended. As will be apparent from the drawings, the cables 20 are designed so that they curve outwardly to maximise the clearance available for reception of the spout when the mount 12 and the ring 15 are in the fully open position and during rotation of the ring relative to the mount to constrict the opening.

It will be understood that the device can be used to constrict the spout before untying it at the start of dispensing to prevent loss of material or indeed to adjust flow rate by varying the aperture of the spout.

It will be appreciated that it is not intended to limit the invention to the described example only, many variations being possible, such as might readily occur to one skilled in the art without departing from the scope thereof. While three cables 20 are illustrated in the drawings, it will be appreciated that a different number may be employed, for instance 4 or more, e.g. 6. Where more than 3 cables are employed, the ends of each cable in the fully open position may be spaced 120° from one another. The connections of the cables to the mount 12 and ring 15 respectively will usually be equiangularly spaced around the mount or ring. Also means may be provided for counteracting wear of the mount and ring components through repeated relative movement. Such means may comprise a wear strip, e.g. a plastic wear strip which may be of annular configuration, located between confronting faces of the mount and ring.

Claims

1. A machine for discharging a container of the kind referred to comprising a hopper-like receptacle for the bottom of a container, a door in the wall of the hopper-like receptacle to give access to the spout of the container to permit tying and untying thereof, and means for constricting the spout of the container located within the hopper-like receptacle and comprising:

(a) a rigid mount having a circular aperture therein through which the spout may be located; (b) a circular ring surrounding said aperture;

(c) a number of cables extending from the rigid mount at spaced locations around the circular aperture to the circular ring at spaced locations around its circumference; and

(d) means for rotating the ring relative to the rigid mount to cause the cables to move from a first position generally following the periphery of the aperture to a second position wherein they cross one another to form a restricted opening capable of constricting the spout of the container.

2. A material flow constricting device for use in a machine of the kind referred to, the device comprising:

(b) a circular ring surrounding said aperture;

3. A machine or device as claimed in Claim 1 or 2 in which the connections of the cables to the mount are equiangularly spaced from one another.

4. A machine or device as claimed in Claim 1, 2 or 3 in which the connections of the cables to the ring are substantially equiangularly spaced from one another.

5. A machine or device as claimed in any one of the preceding claims in which each cables is arranged to curve outwardly between its connections to the mount and the ring.

6. A machine or device as claimed in any one of the preceding claims in which the cables are flexible.

7. A machine as claimed in any one of the preceding claims in which relative rotation is effected by fluid-pressure powered means.

8. A machine as claimed in any one of the preceding claims in which there are at least 4, preferably 6, cables.

9. A machine or device as claimed in any one of the preceding claims in which relative movement is effected by an actuator having a linearly movable component.

10. A machine or device as claimed in Claim 9 in which the linearly movable component of the actuator is coupled to the ring through meshing gear teeth.