GB2379925A

GB2379925A - U-shaped dispensing apparatus

Info

Publication number: GB2379925A
Application number: GB0122774A
Authority: GB
Inventors: Brian Hagen
Original assignee: CARIER BULK MATERIALS HANDLING
Current assignee: CARIER BULK MATERIALS HANDLING
Priority date: 2001-09-20
Filing date: 2001-09-20
Publication date: 2003-03-26
Anticipated expiration: 2021-09-20
Also published as: GB2379925B; GB0122774D0

Abstract

A dispensing apparatus comprising a elongate, substantially U-shaped conduit (2) having an aperture (4) in its base and closure means for said aperture comprising a pair of opposed shutters (6,8) mounted to respective guide tracks (14) arranged for the shutters to follow the substantially U-shaped profile of the conduit when opening and closing around the exterior of the conduit. The shutters (6,8) are arranged such that, with the aperture (4) closed, the upper surface of each shutter lies flush with the interior surface of the conduit (2). As the cross sectional profile of this most compact apparatus is substantially uninterrupted along its length, an accumulation of substances is prevented from occurring which might otherwise result in contamination of a subsequent flow through the conduit.

Description

Dispensing Apparatus The present invention relates to an apparatus for dispensing fluid substances, such as powdered substances.

A variety of dispensing apparatus are known comprising a conduit along which a fluid material may be channelled, for example by means of an Archimedeal screw disposed within the conduit, the base of the conduit being provided with a plurality of outlet apertures which may be selectively opened to allow a quantity of fluid to flow therethrough.

However, a drawback of all known arrangements is that the closure means for each aperture presents a discontinuity in the surface of the conduit, likely to cause an accumulation of substances which can then contaminate subsequent flows of other substances through the conduit.

We have now devised an arrangement which overcomes the limitations of existing dispensing apparatus.

In accordance with the present invention, there is provided a dispensing apparatus comprising: an elongate, substantially U-shaped conduit along which fluid substances may be channelled to be dispensed through at least one aperture in the base of the conduit; and respective closure means for the or each aperture; the or each closure means comprising a pair of opposed shutters mounted to respective guide tracks arranged for the shutters to follow the substantially U-shaped profile of the conduit when opening and closing around the exterior of the conduit and such that, with the aperture closed, the upper surface of each shutter lies flush with the interior surface of the conduit.

It will be appreciated that as the cross sectional profile of this most compact apparatus is substantially uninterrupted along its length, an accumulation of substances is prevented from occurring which might otherwise result in contamination of a subsequent flow through the conduit.

Preferably each shutter is pivotally connected to the

distal, extendible end of at least one respective linear actuator, pivotally mounted to a fixed part of the apparatus. Most preferably the linear actuator comprises a hydraulic or pneumatic actuator.

Preferably the pivotal connection between the shutter and the distal end of the actuator is provided by a rocking arm, arranged to tilt the trailing edge of the advancing shutter into alignment with the conduit, as the distal end of the linear actuator becomes fully extended to close the aperture, and biassed to tilt the same edge out of alignment with the conduit, on commencement of the return stroke of the actuator to open the aperture.

An embodiment of the present invention will now be described by way of an example only and wich reference to the accompanying drawings, in which: Figure 1 is a perspective view of a dispensing apparatus in accordance with the present invention; and Figures 2 to 6 are respective cross-sectional views of the apparatus of Figure 1, along the line A-A', showing the closure means thereof in successive stages of opening.

Referring to Figure 1, a length of substantially"U" shaped conduit 2 is shown, along which powdered substances may be channelled, the base of the conduit being provided with an outlet aperture 4 which is normally closed by a pair of opposed shutters 6,8 but which may be opened by drawing the shutters 6,8 away from one another around the exterior of the conduit 2.

When closed, the upper surfaces of the two shutters 6,8 lie flush with the interior surface of the conduit 2, to provide an uninterrupted surface over which substances may flow, without any substantial accumulation of that substance.

Referring to Figure 2, it can be seen that each shutter 6,8 is provided at either end with a respective pair of lugs or rollers 10,12 which locate within a respective guide track 14. The outermost lugs or rollers 12 at the ends of each

shutter 6,8 are pivotally connected to respective rocking arms 16, the opposite ends of these arms being, in turn, pivotally connected to the distal ends 18 of respective hydraulic actuators 20. A further lug or roller 22 projecting from each rocking arm 16 also locates with its adjacent guide track 14 to provide a fulcrum about which the arm 16 can be rotated to either raise or lower the trailing edge 24 of its associated shutter 6,8.

In the position shown in Figure 2, with each hydraulic actuator 20 fully extended, it can be seen that the trailing edge 24 of each shutter 6,8 is raised into alignment with the conduit 2, due to the outermost lugs or rollers 12 of the shutters 6,8 being pressed upwards within their respective guide tracks 14.

Following the sequence of operations illustrated in Figures 3 to 6, a partial retraction of the distal ends 18 of each of the hydraulic actuators 20 first releases the leverage forces on each of the rocking arms 14, allowing respective biassing springs 26, connected between the proximal end of each rocking arm 14 and its associated shutter 6,8, to lower the trailing edges 24 of the shutters 6,8 downwards and out of alignment with the conduit 2 (Figure 3).

A further retraction of the distal ends 18 of the hydraulic actuators 20 then causes the lugs or rollers 10,12 at the front and rear of each shutter 6,8 to travel along their respective tracks 14, thereby drawing the shutters 6,8 (now free of the edges of the aperture 4 in the conduit 2) around the sides of the conduit 2 (Figures 3 to 6), as the hydraulic actuators pivot about respective axes 28.

The apparatus thus described is most compact and, in having a substantially uninterrupted cross sectional profile along its length, prevents an accumulation of substances which might otherwise result in contamination of a subsequent flow of substance through the conduit.

Claims

Claims 1) A dispensing apparatus comprising: an elongate, substantially U-shaped conduit along which fluid substances may be channelled to be dispensed through at least one aperture in the base of the conduit; and respective closure means for the or each aperture; the or each closure means comprising a pair of opposed shutters mounted to respective guide tracks arranged for the shutters to follow the substantially U-shaped profile of the conduit when opening and closing around the exterior of the conduit and such that, with the aperture closed, the upper surface of each shutter lies flush with the interior surface of the conduit.
2) A dispensing apparatus as claimed in Claim 1, wherein each shutter is pivotally connected to the distal, extendible end of at least one respective linear actuator, pivotally mounted to a fixed part of the apparatus.
3) A dispensing apparatus as claimed in Claim 2, wherein the or each linear actuator comprises a hydraulic or pneumatic actuator.
4) A dispensing apparatus as claimed in Claim 2 or Claim 3, wherein the pivotal connection between the shutter and the distal end of the actuator is provided by a rocking arm, arranged to tilt the trailing edge of the advancing shutter into alignment with the conduit, as the distal end of the linear actuator becomes fully extended to close the aperture, and biassed to tilt the same edge out of alignment with the conduit, on commencement of the return stroke of the actuator to open the aperture.
5) A dispensing apparatus substantially as herein

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described with reference to the accompanying drawings.