US20010027822A1

US20010027822A1 - Material discharge apparatus

Info

Publication number: US20010027822A1
Application number: US09/739,364
Authority: US
Inventors: Umberto Bertolo
Original assignee: Individual
Current assignee: Control and Metering Ltd
Priority date: 2000-04-07
Filing date: 2000-12-19
Publication date: 2001-10-11
Also published as: CA2304916A1

Abstract

An apparatus for discharging a flowable material from a container having a discharge duct comprises support means for supporting the container, preferably in the form of a conical hopper having a central aperture, a clamping enclosure extending downwardly from the hopper, a discharge duct having its mouth located inside the enclosure and facing upwardly towards the aperture in the hopper, and an annular clamping ring inside the enclosure, the ring being movable so as to clamp the spout of the container against the mouth of the discharge duct. Preferably, the enclosure is substantially sealed, with reclosable access openings provided in a front wall of the enclosure through which the spout of the container can be manually handled. The enclosure is also provided with vacuum means to create a negative pressure in the enclosure and therefore prevent release of the contents of the container into the atmosphere.

Description

FIELD OF THE INVENTION

The present invention relates to material handling equipment, and more particularly to an apparatus for discharging a powdered material from a flexible intermediate bulk container.

BACKGROUND OF THE INVENTION

Flexible intermediate bulk containers, also known as “bulk bags”, typically comprise an outer bag and an inner liner having a tubular spout. Such containers are used for the transfer of a wide range of solid materials including foodstuffs and pharmaceuticals, which must be protected from contamination. The outer bag can be used many times by inserting a replacement liner each time the bag is used. The liner prevents contamination of the product inside the bag and provides some measure of protection to the contents should the outer bag become damaged. The tubular spout of the inner liner is normally completely enclosed in the outer bag and is exposed prior to discharge of the material by folding back a flap in the outer bag and pulling the spout out of the outer bag.

A typical apparatus and method for discharging powdered materials from a flexible intermediate bulk container are described in U.S. Pat. No. 4,946,071 to Poulton, issued on Aug. 7, 1990. As illustrated in FIGS. 2 and 3 of Poulton, a container is delivered to the vicinity of the discharge apparatus on a pallet, and is then suspended by loops from a rigging frame and lifted by a fork-lift truck, at which point a flap on the outer bag is pulled aside to expose the spout. The flexible intermediate bulk container is then lowered onto a conical hopper such that the spout projects downwardly through a central hole in the hopper. The spout is then untied and pulled down to engage an upturned cuff over the mouth of a discharged duct. As shown in FIGS. 4 and 5 of the Poulton patent, a clamping ring is then lowered downwardly to clamp the spout of the inner liner against the mouth of the discharge duct. Discharge is then effected.

The use of the Poulton apparatus prevents contamination of contents of the container and release of the contents into the atmosphere during discharge of the container. However, the Poulton apparatus has the disadvantage that, during engagement and disengagement of the spout with the discharge duct, some amount of material is inevitably released into the atmosphere, resulting in contamination of the air in the vicinity of the apparatus and possibly resulting in contamination of the contents of the container. Poulton has the additional disadvantage that the distances between the hopper, the clamping ring and the discharge duct are such that the Poulton device can only be used with containers having very long spouts, typically about 36 to 40 inches. This is much longer than the standard spout length of 17 to 20 inches used in most flexible intermediate bulk containers.

Therefore, there is a need for a improved material discharging apparatus which overcomes these problems.

SUMMARY OF THE INVENTION

The present invention overcomes the above-mentioned disadvantages by providing a discharge apparatus in which a substantially sealed enclosure is provided below a hopper on which a flexible intermediate bulk container is supported.

In the apparatus of the invention, the lower end of the hopper extends into an upper region of the sealed enclosure, such that the aperture in the hopper is spaced above the mouth of a discharge duct, which extends upwardly into the sealed enclosure. The enclosure also contains a clamping ring which clamps the spout of the inner bag against the mouth of the discharge duct.

In the apparatus of the invention, the spout is manually pulled down over the mouth of the discharge duct through one or more reclosable access openings in the enclosure. The clamping rings then lowered to clamp the bag spout against the mouth of the discharge duct. Preferably, the enclosure is under a negative pressure so that release of material into the atmosphere during handling of the spout and discharge of the material is effectively prevented.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described, by way of example only, with reference to the following drawings, in which: [0009]
FIG. 1 is a front elevational view of a portion of a discharge apparatus according to the present invention, showing the preferred clamping enclosure; [0010]
FIG. 2 is a cross-sectional view of the clamping enclosure of FIG. 1, after the spout of the bag liner has been drawn over the mouth of the discharge duct; [0011]
FIG. 3 is a cross-sectional view of the clamping enclosure of FIG. 1, illustrating clamping of the bag spout between the clamping ring and the mouth of the discharge duct; and [0012]
FIG. 4 is a close up view of area A in FIG. 3.[0013]

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

A preferred embodiment of the invention will now be described with reference to FIGS. [0014] 1 to 4.
FIG. 1 illustrates a front elevational view of a portion of a preferred apparatus [0015] 10. It will be appreciated that components of apparatus 10 which are not shown in the drawings are conventional and are similar to those shown in the above-mentioned Poulton patent, which is hereby incorporated by reference in its entirety.
FIG. 1 illustrates a flexible [0016] intermediate bulk container 12 which is preferably suspended from a hoist by loops as shown in the Poulton patent. As illustrated in FIGS. 2 and 3, the flexible intermediate bulk container 12 comprises an outer bag 13 and an inner liner 15 with a discharge spout 17. Access to the spout 17 is provided by folding back a flap 11 provided in the outer bag 13.
The flexible [0017] intermediate bulk container 12 is at least partially supported by hopper 14, which comprises support walls 18 surrounding an aperture 20 (shown in FIG. 2) sized to receive discharge spout 17. Preferably, the hopper 14 has a truncated conical shape, with the support walls 18 radiating outwardly and upwardly from the aperture 20. Preferably aperture 20 is substantially centrally located in a lower end of the hopper 14. In one particularly preferred embodiment, the support walls 18 of hopper 14 are inclined at an angle of about 30 to 40° to the horizontal, more preferably about 35°.
Preferably, the hopper is supported atop [0018] vertical support members 16 which preferably extend downwardly to the floor of a work area.
As illustrated in FIG. 2, the lower end of [0019] hopper 14 extends downwardly through an upper wall 24 of a clamping enclosure 22. As shown in the drawings, clamping enclosure 22 also comprises a front wall 26, a pair of side walls 28, a rear wall 30 and a bottom wall 32. The clamping enclosure 22 is substantially sealed with the exception that it is open to the aperture 20 of hopper 14. During use of the apparatus 10, the aperture 20 is effectively sealed by container 12.
The front wall of [0020] clamping enclosure 22 is provided with at least one reclosable access opening, preferably two openings 34 as illustrated in FIG. 1. Each access opening 34 is substantially rectangular, being covered by a resilient membrane, such as rubber, the membrane 36 having a slit 38 extending vertically along substantially its entire height. The slit is provided to allow access for an operator to manually manipulate the spout of the bulk container inside the enclosure 22. Preferably, the front wall 26 of enclosure 22 is comprised of a transparent material such as poly(methyl methacrylate) to allow the operator to visually confirm proper positioning of the discharge spout 17 inside enclosure 22.
A [0021] discharge duct 40 extends vertically upwardly through bottom wall 32 of clamping enclosure 22 such that the open mouth 42 of duct 40 is contained inside enclosure 22. The mouth 42 mouth which faces upwardly toward the aperture 20 and is spaced below aperture 20 by a distance sufficient to allow the discharge spout 17 to be pulled down over the mouth 42 of the discharge duct 40 in the manner shown in FIG. 2. Preferably, the discharge duct 40 is provided at its mouth 42 with a cylindrical, horizontal upper face 44.
Also enclosed within [0022] clamping enclosure 22 is an annular clamping ring 46 having an inner diameter which is sized to receive the discharge spout 17 of the container 12 and an outside diameter sized to clamp the open mouth 42 of the discharge duct 40. The annular clamping ring 46 is movable between an upper position shown in FIG. 2 and a lower position shown in FIGS. 3 and 4. In the upper position, the ring 46 is spaced above the open mouth 42 of the discharge duct. In its lower position, a clamping surface 48 of clamping ring 46 clamps the discharge spout 17 against the upper face 44 of the discharge duct 40.
Preferably, the [0023] clamping surface 48 of annular clamping ring 46 is provided with resilient sealing means to sealingly clamp the spout of the bag against the upper face 44 of discharge duct 40. Preferably, in the embodiment shown in the drawings, the resilient sealing means comprises a rubber O-ring 49 which is received in a groove 51 in the clamping surface 48 of clamping ring 46.
The apparatus [0024] 10 also provides means for moving the clamping ring 46 between its upper and lower positions. Preferably, as illustrated in the drawings, the means for moving the clamping ring 46 comprises a pair of hydraulic cylinders 50 located outside and adjacent to enclosure 22. Each hydraulic cylinder 50 is connected to the clamping ring 46 by a horizontal linkage 52 having one end connected to a cylinder 50 and an opposite end connected to clamping ring 46 through side wall 28. In a particularly preferred embodiment, the clamping ring 46 and the linkages 52 are integrally formed. In order to accommodate the vertical movement of the clamping ring 46 and linkages 52, the side walls 28 of enclosure 22 are preferably provided with elongate openings 53 having resilient sealing means (not shown) to prevent the release of material from the enclosure 22.
The apparatus [0025] 10 is also provided with vacuum means to create a negative pressure inside the enclosure 22, thereby substantially preventing release of material into the atmosphere from inside the enclosure 22. The vacuum means preferably comprises a vacuum device (not shown) which applies suction to the enclosure 22 through an exhaust port 54 provided in the rear wall 30 of the enclosure 22. Preferably, a shown in the drawings, a horizontal plane in which the mouth 42 of the discharge duct 40 is also located also passes through the exhaust port 54, so that the exhaust port 54 is in close proximity to the mouth 42 of duct 40 and the end of discharge spout 17, where most material would be released during handling of the spout 17. Preferably, the horizontal plane passes substantially centrally through the exhaust port 54.
It will be appreciated that the apparatus [0026] 10 of the present invention also includes a number of other conventional components which have not been shown in the drawings. For example, the apparatus 10 also comprises a hoist by which the container 12 can be raised and lowered relative to hopper 14.
The operation of the apparatus [0027] 10 will now be described below.
Firstly, the flexible [0028] intermediate bulk container 12 is transported to the vicinity of the apparatus 10 on a pallet as shown in FIG. 2 of the Poulton patent. The container is then lifted as in FIG. 3 of the Poulton patent and the flap 11 of the outer bag 13 is pulled back to reveal the spout 17 of the inner liner 15. The container 12 is then transferred to a hoist and is lowered onto the hopper 14 so that the spout 17 extends downwardly through aperture 20. An operator then extends his or her hands through the reclosable openings 34 to pull the spout 17 down over the open mouth 42 of discharge duct 40. The operator then removes his or hand from the opening 34 and the clamping ring 46 is lowered by hydraulic cylinders 50 until the spout of the bag is securely clamped between the clamping surface 48 of clamping ring 46 and the upper face 44 of discharge duct 40. This is shown in the close up view of FIG. 4. After discharge of the material is complete, the hydraulic cylinders are operated to raise the clamping ring from the mouth 42 of discharge duct 40. The operator then ties the spout of the bag and it is removed from the hopper 14. During the entire time that container 12 is supported on hopper 14, the vacuum means is operated to prevent release of material from the enclosure.
Although the preferred embodiments of the invention have been described in conjunction with a flexible intermediate bulk container shown in the Poulton patent having a flap which must be pulled aside to reveal spout, the invention can be used with other types of containers having spouts, including most conventional flexible intermediate bulk containers having standard length spouts. [0029]
Although the invention has been described in connection with certain preferred embodiments, it is not to be limited thereto. Rather, the invention includes all embodiments which may fall within the scope of the following claims. [0030]

Claims

What is claimed is:

1. An apparatus for discharging a flowable material from a container having a discharge spout, comprising:

(a) support means for supporting said container, said support means comprising support walls surrounding an aperture sized to receive the discharge spout of the container;

(b) a substantially sealed clamping enclosure extending downwardly from, and sealingly fixed to, said support means, said enclosure having a front wall, side walls a bottom wall and an upper end which is open to said aperture, said front wall provided with at least one reclosable access opening allowing manipulation of said discharge spout inside the enclosure;

(c) a discharge duct having an open mouth located inside said enclosure and facing upwardly toward said aperture, said mouth of said discharge duct being spaced below said aperture by a distance sufficient to allow the discharge spout of the container extend over the mouth;

(d) an annular clamping ring inside said enclosure, said annular clamping ring having an inner diameter sized to receive the discharge spout of the container and an outside diameter sized to clamp the open mouth of the discharge duct, the annular clamping ring being movable between an upper position at which the ring is spaced above the open mouth of the discharge duct and a lower position at which the ring engages the open mouth of the discharge duct;

(e) moving means to move said clamping ring between the upper and lower positions; and

(f) vacuum means to create a negative pressure inside said enclosure, thereby substantially preventing release of said material into the atmosphere from inside said enclosure.

2. The apparatus of

claim 1

, wherein said support means is of a truncated conical shape, with said support walls radiating outwardly and upwardly from said aperture which is substantially centrally located in a lower end of said support means.

3. The apparatus of

claim 2

, wherein said support walls are inclined at an angle of about 30 to 40 degrees to the horizontal.

4. The apparatus of

claim 1

, wherein the enclosure additionally comprises a rear wall opposite said front wall, and wherein said vacuum means comprises an exhaust port in the rear wall, and a vacuum device which applies suction to the enclosure through said exhaust port.

5. The apparatus of

claim 1

, wherein said mouth of said discharge duct is located in a horizontal plane which passes through said exhaust port.

6. The apparatus of

claim 5

, wherein the horizontal plane passes substantially centrally through the exhaust port.

7. The apparatus of

claim 1

, wherein the discharge duct is provided at its mouth with a cylindrical, horizontal upper face which is engaged by said annular clamping ring during clamping.

8. The apparatus of

claim 1

, wherein the annular clamping ring has a lower clamping face provided with resilient sealing means for sealingly clamping the discharge spout of the container against the upper face of the discharge duct.

9. The apparatus of

claim 1

, wherein the front wall of the enclosure is provided with two of said access openings, the openings being located to either side of a vertical axis passing centrally through said aperture and the mouth of the discharge duct.

10. The apparatus of

claim 9

, wherein each of said access openings is closed by a resilient membrane, said membrane having a slit allowing access through the access opening.

11. The apparatus of

claim 1

, wherein said moving means comprises a pair of hydraulic cylinders located outside the enclosure and linkages connecting said hydraulic cylinders to said annular clamping ring.

12. The apparatus of

claim 11

, wherein each of said linkages passes through an opening in a side wall of the enclosure between its associated hydraulic cylinder and the annular clamping ring, the openings in the side walls being elongate and having sealing means to prevent release of the material.