GB2101569A

GB2101569A - Apparatus for assisting the discharge of materials from bins, hoppers or the like

Info

Publication number: GB2101569A
Application number: GB08121750A
Authority: GB
Inventors: Barrie A Poulton
Original assignee: FLOWMAT Ltd
Current assignee: FLOWMAT Ltd
Priority date: 1981-07-14
Filing date: 1981-07-14
Publication date: 1983-01-19

Abstract

A hopper-like container (10) comprising a baffle (18) over the discharge opening and secured to the container by rigid members (17, 16, 15 and 14), has vibrator means (20), e.g. a pneumatically powered turbine vibrator, connected to the baffle and adjustable weight means (22) connected to the baffle so that it can vibrate in a resonant mode. <IMAGE>

Description

SPECIFICATION Apparatus for assisting the discharge of materials from bins, hoppers or the like This invention concerns apparatus for assisting the discharge of divided solid materials, such as those of powdered, granulated, chipped or other fragmented form, from a bin or hopper or other storage device of the kind (hereinafter termed of the kind referred to) having a discharge opening at its lower end through which the material may flow under the influence of gravity.

Frequently the discharge opening of a storage device of the kind referred to is of smaller crosssectional area than that of the main body of the device giving rise to numerous discharge problems, principally so-called rat-holing and bridging or arching.

Numerous kinds of apparatus for assisting and promoting discharge of material for storage devices of the kind referred to are known. Perhaps the most successful are those which provide what is known as a "live-bottom bin" wherein that part of the bin of reducing cross-sectional area between the main body of the bin and the discharge opening is flexibly mounted relative to the main body of the bin and equipped with means enabling it, when in use, to be vibrated to promote material flow. Such apparatus, however, tends to be rather costly - precluding its use in many industries and applications.

It is an object of the present invention to provide apparatus for facilitating the discharge of materials from storage devices of the kind referred to which is of comparable performance to the better of earlier known such apparatus, but which is of simple and robust construction and consequently of relatively low cost.

According to the present invention, there is provided apparatus for assisting the discharge of materials from a storage device of the kind referred to and comprising: (a) baffle means located in or over said discharge opening and rigidly connected to the walls of the storage device, (b) vibrator means connected to said baffle means, and (c) weight means connected to said baffle means and adjustable to enable said baffle means to vibrate in a resonant or substantially resonant mode under the influence of said vibrator means.

Preferably the baffle means is of upwardly convex form such as that of a right cone or an inverted dish or dome, for example, and the vibrator means is pneumatically powered, thus providing for safety in explosive or other hazardous environments.

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 apparatus embodying the invention, and fitted to a storage silo or hopper.

Of the drawings: Fig. 1 shows a vertical cross-section through the hopper and the apparatus of the invention; Fig.2 shows a cross-section on the line 11-li of Fig. 1; and Fig. 3 shows a cross-section on the line 111-Ill of Fig. 1.

Referring now to the drawings, it will be seen that the storage hopper 10 is of circular crosssection (in the horizontal plane) and comprises an upper part 1 Oa of constant cross-sectional area and a lower part lOb of diminishing crosssectional area terminating with an outwardly directed flange 1 Oc at its lower end.

The apparatus of the invention, in this example, includes an inverted truncated conical shell 11 whose upper end is provided with an outwardly directed flange 1 a which is securely fixed to the flange 1 Oc as by means of bolts 12. In effect the shell 11 forms an extension to the hopper 10 and defines at its lower end a discharge opening 1 3 (which opening would, in the absence of the shell 11, be at the level of the flange 1 Oc).Two diametrically opposed struts 14 (more may be provided for larger machines) extend inwardly from the inner walls of the shell 11 to support a ring-shaped member 1 5 which carries bracket members 1 6 from which rods 1 7 extend upwardly to mount a baffle means generally indicated at 18. The baffle means 1 8 comprises a right conical shell 1 spa closed at its lower end by a plate 1 8b to which the rods 17 are fixed as by nuts 19, the upper ends of the rods being threaded and the plate 1 Sb being apertured for this purpose.

Mounted on the topside of the plate 1 Sb and beneath the shell 1 spa is a pneumatically powered turbine vibrator20. Air lines for the supply of air to and exhaust of air from the vibrator20 are, of course, provided, but are omitted from the drawings in the interests of clarity.

Depending from the plate 1 8b and rigidly connected to the vibrator20 is a threaded rod 21 having a weight 22, in this example in the form of a secondary upwardly convex baffle, mounted thereon. The position of the weight 22 along the rod21 may be adjusted by means of securing nuts 23.

In use, operation of the vibrator 20 causes the baffle 18 to vibrate with an elliptical motion in a horizontal plane and some vibration is, of course, transmitted to the shell 11 and indeed the hopper 10.

The presence of the baffle 1 8 over the opening 1 3 prevents rat-holing or plug flow and essentially material from the hopper is discharged on a first in first out basis. The inclined walls of the shell 1 8a transmit powerful forces upwardly into material within the hopper 10 and this, combined with the "cutting action" of the peripheral edge of the baffle 1 8 in the annular space between the baffle 1 8 and inner wall of the hopper 1 0, prevents in the main arching or bridging and assures mass flow.

For a given supply of air to the vibrator20, the position of the weight 22 can be adjusted to maximise the vibratory effect -- generally this occurs when the entire moving mass is at or close to resonance.

Tests have shown that the apparatus behaves well even with notoriously difficult materials such as wood shavings and carbon black, for example.

Nonetheless the apparatus is not particularly costly and readily installed either as original equipment or an an enhancement to existing storage devices.

It will be appreciated that it is not intended to limit the invention to the above example only, many variations, such as might readily occur to one skilled in the art, being possible, without departing from the scope thereof.

Claims

1. Apparatus for assisting the discharge of materials from a storage device of the kind referred to comprising: (a) baffle means located in or over said discharge opening and connected to the walls of the storage device by rigid members, (b) vibrator means connected to said baffle means, and (c) weight means connected to said baffle means and adjustable to enable said baffle means to vibrate in a resonant or substantially resonant mode under the influence of said vibrator means.

2. Apparatus according to claim 1 wherein said baffle means is of upwardly convex form.

3. Apparatus according to claim2 wherein said baffle means is in the form of a right conical shell.

4. Apparatus according to claim 2 wherein said baffle means is in the form of an inverted dish or dome.

5. Apparatus according to any preceding claim wherein said baffle means carries a rod which extends downwardly therefrom, said weight means being mounted on the rod in such a manner that its position therealong may be adjusted.

6. Apparatus according to claim 5 wherein said rod is screw-threaded and wherein said weight means is secured by nut means threadedly engaging said rod.

7. Apparatus according to either claim 5 or claim 6 wherein said weight means is in the form of a secondary baffle of upwardly directed convex form.

8. Apparatus according to any preceding claim wherein said vibrator means is pneumatically powered.

9. Apparatus according to any preceding claim wherein said vibrator means acts to vibrate the baffle with an elliptical motion in a horizontal plane.

1 0. Apparatus for assisting the discharge of materials substantially as described herein with reference to and as illustrated by the figures of the accompanying drawings.