GB2028759A - Improvements in and relating to bulk discharge systems - Google Patents

Abstract

A bulk discharge system is described for fitting to a bulk carrier vehicle to allow the latter to draw in bulk material into the vehicle for loading purposes as well as to blow the material out of the vehicle for unloading purposes. To this end a bulk carrier vehicle includes a strengthened container (52) to allow at least a partial vacuum to be generated therein, discharge means (78) associated with the compartment (52) for collecting bulk material from a low region in the compartment and discharging the collected material into a conduit, blower means (100) adapted to produce a partial vacuum within the compartment (52) and for generating a through flow of air through the conduit, inlet means (106) to the compartment (52) and conduit means (104) attachable to the inlet means (106) for conveying to the compartment bulk material under the action of the suction created by the vacuum within the compartment and outlet means associated with the first mentioned conduit through which the discharged material in the conduit is conveyed. An air inlet valve (110) can be opened to allow air to be admitted to the compartment instead of through the conduit means (104). Further valve means (108) is provided for shutting off the inlet conduit means (104). Filters (92) are provided within the compartment to restrict the ingress of dirt and dust into the input to the blower. <IMAGE>

Description

SPECIFICATION Improvements in and relating to bulk discharge systems Field of invention This invention concerns bulk discharge systems for conveying bulk materials such as animal feedstuffs, grain and the like from portable bulk carriers to storage facilities and vice versa.

Background to the invention It has been known for some time to provide bulk carriers with a bulk material outlet which is designed to collect the bulk material and convey it into an air stream generated buy a blower or the like for discharging the bulk contents along a hose or other discharge line. In this way the entire contents of the bulk carrier can be discharged into a silo or barn or other storage facility.

The procedure has many advantages over simply tipping the bulk carrier or by using auger discharge devices.

Whilst the procedure for emptying a bulk carrier has been simplified by use of a blowing technique, the procedure for filling the container at a base or depot has, as yet, not been simplified in this way due to fundamental problems. In general the only method of achieving the suction needed to lift the bulk material such as grain or animal feedstuffs from a silo or grain store into the vehicle is to create a vacuum within the vehicle and the structure of the bulk carrier is not such as will allow the creation of an internal vacuum. Other methods have been used involving the use of cyclones but these have not proved satisfactory in practice and the idea has been disbanded for many years.

Hitherto the general methods of filling a bulk carrier have been by using overhead hoppers, conveyor belts or auger collection devices.

The use of conveyor belts and augers is slow and tedious and in no way, under normal circumstances, equates to the rate of discharge of the material from the bulk carrier which can be achieved using the blowing devices currently available. The use of overhead hoppers is of course quicker and whilst these maybe convenient for large scale industrial applications, the typical bulk materials such as grain and animal foodstuffs are not normally at such a level on farms and similar places as will allow them to be conveyed into the bulk carrier from overhead as is required by the hopper technique.

Objects of the present invention With these disadvantages in mind it is an object of the preset invention to provide a suction filling system by which a bulk carrier can be filled with bulk material such as grain or animal foodstuffs.

It is another object of the present invention to utilise the existing blowing equipment mounted on a bulk carrier to generate the appropriate suction and allow a bulk material to be conveyed into a bulk carrier.

The invention According to the present invention in a bulk carrier vehicle, a portion of the bulk carrying container is strengthened to allow at least a partial vacuum to be generated therein, discharge means associated with the compartment for collecting and discharging bulk materials from a low region in the compartment into a conduit, means for creating a vacuum within the said compartment and for generating a through flow of air through the said conduit, inlet means to the said compartment and conduit means attachable thereto for conveying to the compartment bulk material under the action of the suction created by the vacuum generated within the compartment, and outlet means associated with the conduit through which the discharge material in the conduit is conveyed.

Preferably the means for generating the through flow of air in the said conduit comprises a rotary pump driven by the vehicle engine and the air input pump is via the said compartment, Preferably the compartment includes an air inlet valve which can be opened to allow air to be admitted to the compartment from where it is drawn by the input to the blower.

Preferably filter means is provided within the compartment to prevent ingress of dirt and dust from the compartment into the input to the blower.

Preferably means is provided whereby the discharge device which communicates with the lower region of the compartment can be shut off from an upper region of the compartment so as to communicats with the remainder of the interior of the bulk carrier whereby the discharge device can operate in its known conventional manner to collect bulk material and convey it into the air stream in the conduit produced by the blower. In this mode of operation (the known mode of operation) the air inlet to the said compartment is opened and the bulk material inlet is closed so that air only is admitted into the compartment. Preferably filter means is provided within the compartment through which incoming air has to pass before it can be conveyed to the input to the blower so as to prevent the ingress of dust and dirt to the blower.

Preferably the filter means comprise a plurality of filter bags which communicate with a manifold at the upper end of the chamber and hang down into the chamber. Typically the manifold communicates via a pipe line with the input to the blower.

Conveniently at least one in-iine filter is provided in the pipe line between the manifold and the inlet to the blower to further reduce the risk of dirt or dust entering the inlet to the blower.

Preferably the means for shutting off the upper part of the compartment from the discharge unit is operable from outside the bulk carrier and is adjustable into a second position in which the discharge unit communicates with theinterior of the said compartment and the compartment is now sealed off entirely from the remainder of the bulk carrying compartment of the vehicle. In this position the bulk material inlet to the compartment is opened and the air inlet to the compartment is closed and a flexible conduit or similar is connected to the bulk material inlet, the remote end of which is pushed into the bulk material which is to be drawn into the bulk carrier.

Subsequent operation of the blower causes airto be drawn through the flexible conduit through the bulk carrier inlet into the compartment and through the filter means and as before via the appropriate pipework etc. to the input to the blower. The ingress of air into the remote end of the flexible conduit causes the bulk material to be drawn into the flexible conduit with the air resulting in a restriction in the cross-sectional area within the flexible conduit which causes a further drop in the pressure in the compartment which effect is cumulative since this causes a greater suction of air and material into the free end of the flexible conduit etc.Depending on the nature of the bulk material a greater or lesser vacuum is established within the said compartment until the bulk material is freely flowing into the compartment with the air needed to prevent the compartment from becoming even further evacuated. The bulk material inlet into the compartment is preferably located at an elevated position within the compartment so that as the air and bulk material enters the compartment, the air is sucked upwardly through the filter and the bulk material being more dense drops away in a generally downward direction towards the discharge unit.

Operation of the discharge unit in a conventional manner causes the bulk material to be removed from the lower region of the compartment into the air stream in the said conduitwhich is produced by the output from the blower.

By connecting the output of the said conduit via an appropriate pipeline to a discharge conduit communicating with the interior ofthe bulk carrier, so the bulk material in the said conduit will be blown through the output thereof along the conduit and into the bulk carrier. The net effect is that bulk material from the silo or barn or other store or heap will be sucked up the inlet conduit and finally conveyed into the bulk carrier at a high rate of flow.

The great advantage of the invention is that existing equipment which has conventionally been supplied to bulk carriers for discharging the contents of the carrier may be used to refill the carrier so that the conversion of an existing blow discharge bulk carrier so as to embody the invention and allow the carrier to be suction filled can be achieved at relatively low cost.

The invention lies not only in a bulk carrier when modified so as to provide for suction filling of the carrier but also resides in apparatus for converting an existing blow discharge bulk carrier to embody the invention comprising means for providing a strengthened compartment as part of the bulk carrier, means for causing the said strengthened compartment to communicate with the existing discharge device or to seal off the discharge device from the compartment and allow the discharge device to communicate with the interior of the bulk carrier in known manner, valve means for controlling the flow of air into the strengthened compartment, further valve means for controlling the inflow of bulk material into the said compartment, and filter means for separating dust and dirt and bulk material from the air entering the compartment and means for conveying filtered air from the compartment to the input to the conventional blower provided in such a bulk carrier.

The apparatus for converting an existing bulk carrier may also include flexible hose means for connecting the output of the conduit means to the interior of the bulk carrier. Where the latter is divided into separate compartments, preferably fixed conduits means is provided for conveying bulk material into the separate compartments selectively and valve means is provided for controlling the inflow of bulk material into the said separate compartments.

The invention also lies in the method fo filling a bulk carrier with bulk material which can be conveyed in an air stream, comprising the steps of establishing at least a partial vacuum in a sealed compartment which communicates with the conventional discharge device associated with the bulk carrier, causing bulk material to be conveyed into the said compartment from a supply of the said bulk material as a result of suction action induced by the partial vacuum in the said compartment, causing the incoming air and bulk material to be separated within the compartment and causing the bulk material to fall within the compartment to be collected by the known discharge device, operating the latter so as to convey the collected bulk material into a conduit, establishing a through flow of air along the conduit and conveying the air and bulk material flowing along the conduit into the bulk carrier to fill the latter.

The establishment of the partial vacuum may be simultaneous with the step of establishing the through flow of air in the conduit by using a common blower.

The invention will now be described by way of example with reference to the accompanying drawings in which: Figure lisa diagrammatic view of a bulk carrier fitted with a known blow discharge facility for removing the bulk material from within the carrying container, Figure 2 is a diagrammaticviewofa known method of filling the bulk carrier container using a portable auger feed, Figure 3 is a side view of the rear end of a bulk container fitted with a special compartment and valve means for enabling the existing blow discharge equipment to supply bulk material to the interior of the bulk carrying container to fill the latter by suction, Figure 4 is a rear view of a bulk carrier part of which is shown in Figure 3, Figure 5 is a plan view from above of the bulk carrier shown in Figures 3 and 4, Figure 6 is a diagrammatic view showing the air flow in the fill/discharge system of the bulk carrier shown in Figures 3 to 5 and Figure 7 is a rear end view of part of the bulk carrier shown in Figures 3 to 5 showing the form of construction of the upper end of the strengthened compartment and the form of construction and fixing of the airfiltertherewithin.

Referring first of all to Figures 1 and 2, a bulk carrier typically comprises a motor vehicle cab 10 mounted at the front end of a chassis 12 having road wheels 14 and 15 which support a bulk material carrying container 16. The latter is usually adapted to be tilted about a lower rear transverse axis 18 typically by means of a pneumatic ram (not shown) in the direction shown by the arrow 20. In this way bulk material contained within the container 16 can be tipped to the rear lower end of the container.

As shown in Figure 2, the rear end may include an aperture covered by a plate 22 through which the bulk material can be tipped but as has hitherto become common practice, alternatively, a pneumatic discharge system is provided such as that offered by Bulkerpart of Oldfield Lane, Wisbech, Cambridgeshire in which a rotary valve 24 communicates with an aperture (not shown) in the floor of the container 16 at the rear end thereof and the output from the rotary valve 24 communicates with a cylindrical conduit 26 through which air is blown from a blower 28 via a pipeline 30. Typically an air filter 32 is provided for filtering the air to the input to the blower 28. Typically the blower is a Roots type blower such as is manufactured in the United Kingdom by Wade (Type VR1 13, VR142 orVR170) or by Peabody Holmes (Type RB68 or RB613).

The rotary valve includes a driven spindle on which blades are mounted typically at an angle of S the blades making a good sealing contact with the interior of the casing of the valve so that as material drops between the blades of the rotor as the latter rotates, it is communicated around the interior of the casing to the exit where it falls out under gravity.

The rush of air through the cylindrical conduit 26 blows the discharged material into a flexible pipeline 34 for feeding the discharged material to wherever it is required.

Figure 2 shows how the conventional bulk carrier is filled using a portable auger. The bulk carrier vehicle is located adjacent the heap or store of bulk material such as grain and designated by reference number 36. The portable auger generally designated 38 is located with the inlet end 40 in the heap of bulk material 36 and with the exit end 42 over the open upper end of the container 44 of the bulk carrier vehicle. The auger 38 is supported by a framework 46 which includes a drive for the auger 50 which is located centrally of the tubular casing forming the auger housing 38. Rotation of the auger 50 within the casing lifts the bulk material and discharges it into the bulk carrier container.

As has hitherto been mentioned, this normal procedure using an auger is not only time consuming but also requires the tying up of the portable auger in the form of capital equipment either on the farm or at the grain store or other bulk material storage depot. The auger will stand idle for long periods of time and in accordance with the invention a more efficient method of removing bulk material from the store or heap such as 36 is provided.

Figures 3 to 7 illustrate one embodiment of the invention.

The embodiment shown in Figures 3 to 7 represents a modification of the bulk carrier vehicle shown in Figure 1 and to this end the same reference numerals have been used to designate common parts.

At the rear of the container 16 a compartment 52 is formed by means of a transverse internal wail 54 and a hinged flap 56 which can either occupy a vertical position as shown in which the compartment 52 is completely sealed from the remainder of the bulk material container 16 and a horizontal position shown in dotted outline in which the lower section of the compartment 52 is now sealed off from the remainder and forms part of and communicates with the remainder of the bulk material container 16.

Winch handle 58 extends laterally on one side of the container 16 and rotation of this handle produces a corresponding rotation of the flap 56.

A series of cams such as 62 shown in Figure 3 are carried by a rotatable bar 64 which also extends trasversely across the container 16. Torque bars 66 and 68 are secured to the protruding ends of the bar 64 and the cams such as 62 can be rotated either in an anti-clockwise manner as shown in Figure 3 so as to allow the flap 56 to swing into and out of the vertical position or can be swung in the opposite direction (i.e. clockwise) so as to engage the rear of the flap 56 as shown in Figure 3 to seal the flap 56 against a bulkhead 70. A rubber seal 72 is provided to ensure that the flap 56 is an airtight fit against the bulkhead 70.

A similar seal 74 is rovided between the upper edge of the flap 56 to seal this upper end against a second bulkhead 76.

As is conventional, a discharge auger 78 extends transversely across an opening 80 in the floor of the container 16 at the rear end thereof and the discharge auger 78 includes two counter-rotating sections so that bulk material is drawn laterally from the opposite ends of the auger 78 towards the centre.

The discharge auger 78 is located immediately above a rotary valve 82 which includes a plurality of transversely extending vanes which are rotated (driven) by a motor (not shown) so that bulk material falling into the pockets between the radial vanes is rotated around and in a generally clockwise manner as shown in Figure 3 to exit through an outlet 84. The bulk material drops out of each of the spaces between the radially protruding vanes and drops through the opening 84 into a cylindrical transverse ly extending pipe or conduit 86 through which air is blown at a controlled rate. The effect is to pick up the bulk material which is discharging into the conduit 86 and a flexible hose 88 connected to the output end of the conduit 86 allows output from the conduit to be supplied to the interior of the container 16.

Operation of the auger 78, rotary valve 82 and conduit 86 is identical to that of the existing equipment such as the pneumatic discharge system as marketed by Bulkerpart of Oldfield Lane, Wisbech, Cambridgeshire. With the flap 56 in the horizontal position (i.e. as shown dotted in Figure 3) the auger 78 is exposed to the bulk material (if any) situated within the remainder of the container 16 and by tilting the container 16 about the rear end so that the forward end of the container 16 is elevated relative to the rear end of the container, so the bulk material contained within the container section 16 can be gravity fed to the auger 78 and rotary valve 82.

With the flap 56 in the vertical position and sealed by the cams 62, the whole of the interior of the chamber 52 becomes sealed off relative to the remainder of the interior of the bulk material container 16 and in this position so also is the discharge auger 78 and rotary valve 82 sealed off from the contents of the bulk material within the bulk material container 16.

The upper end of the chamber 52 is formed as a manifold generally designated 90 which cmmunicates with the remainder of the interior of the chamber 52 by means of apertures and fabric filters such as 92 each of which is in the form of a narrow bag or sock which hangs down into the chamber 52.

Air can pass through the material forming the bags or socks and through the apertures into the manifold section 90 and is collected via an aperture 94 and conveyed via a pipeline 96 (shown in dotted outline in Figure 3) and via an in-line filter 98 to the input of a Roots type blower 100. The output of the blower is connected via pipeline 102 to the input end of the conduit 86. When the blower 100 operates, air is sucked from the manifold 90 via pipeline 96 to the blower and from thence along pipeline 102 and through the conduit 86 to pick up any bulk material which is falling through the rotary valve 82 and to blast this bulk material through the flexible hose 88.

The latter thus forms the outlet from which the bulk material is ejected by means of the air blast in the conduit 86. The ejected material can be directed into a hopper or silo or under certain circumstances can be used to fill the bulk material container 16.

Bulk material which is to pass via the discharge auger 78 and through the rotary valve 82 to the conduit 86 may come from two places.

On the one hand, with the flap 56 in the horizontal position as shown in Figure 3, the contents of the container 16 are exposed to the discharge auger 78 etc. and these contents will be passed through the rotary valve 82 and via the conduit 86 to the discharge pipe 88.

When operating in this mode an inlet hose 104 is shut off from an inlet 106 by closing a valve 108.

Instead an air inlet valve 110 is opened to allow air to enter the interior of the chamber 52 and provide the input to the blower 100 in the manner previously described.

With the flap 56 in the vertical position as shown in solid line in Figure 3, the air inlet valve 110 is closed and the other inlet valve 108 is opened. Air will now be sucked up the hose 104 through the open valve 108 and through the inlet 106. By dipping the end 113 of the hose 104 into a heap or store of bulk material, so the inrush of air into the open end 113 will draw in with it some of the bulk material from the heap or store and this will enter the chamber 52 via the entrance 106. Once within the chamber 52 the air and solid matterwill become separated due to the higher density of the bulk material. However, this separation is assisted by including a chute 107 beyond the entrance 106 which directs the incoming solid matter in a generally downward direction, so that it falls directly into the opening 80 to the rotary valve 82.The incoming air travels upwards through the filters into the manifold 90 and thence to the input to the blower 100.

It will be seen that the blower 100 provides the throughput of air through the conduit 86 at all times and bulk material passing through the rotary valve 82 with the flap 56 in the vertical position as shown in solid outline in Figure 3, will correspond to the bulk material which is entering the compartment 52 via the hose 104. Where operating in this mode therefore the exit end of the hose 88 communicates with the interior of the container 16 and bulk material sucked up through the hose 104 can therefore be supplied via the hose 88 to the interior of the container 16tofill same.

Figure 6 shows the air flow through the system of Figures 3 to 5. Where appropriate the same reference numerals have been used as have been employed in Figures 3 to 5.

The container 16 is divided internally by partitions 112 and 114 which are either hinged at the top or include a hinged section at the bottom, together with locking means (not shown), to allow the contents of compartments 118 and 122 to be retained if desired, whilst the contents of 126 are tipped. A fixed feeder pipe 1 feeds compartment 118 and compartments 122 and 126 are fed by fixed feeder pipes 120 and 124 respectively. Within the rearmostcompartment is located the sealed off chamber 52 and the pipeline 96 extends to the manifold section 90 at the upper end of the sealed off chamber 52.

An in-line filter 98 additionally filters the air before it proceeds to the inputotthe blower 100.

Butterfly valves 128, 129,130 and 131 control the flow of air and bulk material to the separate compartments 118, 122 and 126 and in this way the container 16 can be filled selectively by means of different bulk materials.

Avacuum gauge 132 is provided as is also a vacuum relief valve 134 and a pressure relief valve 136 on the appropriate sides of the blower 100. A pressure gauge 138 is provided on the output side of the blower.

In orderto prevent unwanted reverse flow, a non-return valve 140 is provided and downstream from this non-return valve 140 the pipe-line becomes the conduit 86 which is associated with the rotary valve 82. Bulk material discharged from the rotary valve into the conduit 86 is then blown in the direction of the arrow 142 and depending on the selected position of the flexible connection, the air and bulk material can either be conveyed via the fixed pipes 144and 124,120 or 116 into the various compartments of the container 16 or via a pipe-line 146 to a bin or silo or other storage device into which material from the container 16 is to be discharged.

The bulk material input 106 communicates via a flexible pipeline 104, the remote end of which is pushed into a heap of the bulk material such as 148 so that when the flap 56 (not shown in Figure 6) is in the vertical position as shown in Figure 3, and valve 108 is opened and valve 110 is shut, bulk material from the heap 148 can be sucked through the flexible hose 104 into the sealed compartment 52 and from thence along the conduit 86 in the direction of arrow 142 to be discharged into the container 16 for filling the latter.

Figure 7 shows in greater detail the preferred form of the filter assembly.

Where a Roots type blower is to be fitted, it is essential that the air as supplied to the inlet to the blower is free from dust and dirt particles and to this end in addition to the in-line filter 98, a very large area fabric filter is formed within the compartment 52. The large area is obtained by suspending a large number of sleeves of polypropylene open weave fabric or a similar material so that the sleeves hang down below a bulkhead 150 which is apertured to receive the sleeves. The open ends of the sleeves are splayed out on the upper surface of the bulkhead 150 and are trapped between the bulkhead 150 and retaining plates 152 which are similarly apertured and are bolted to the bulkhead 150.

The sleeves (only two of which are shown in Figure 7) are generally designated by reference numeral 154 and the lower ends are secured either by means of tape or rings or any other suitable securing means to a massive rod or bar 156 which extends transversely across the interior of the compartment 52. As the vehicle moves the bar 156 will shake and vibrate causing the sleeves which suspend the bar also to shake and vibrate. This will tend to shake off the dust and dirt which will collect on the external surfaces of the sleeves and this will simply be dropped to the bottom of the sealed compartment 52 and will leave the compartment with the next charge of bulk material.

Where artificial shaking of the sleeves is desired, a handle 158 is provided, the position and length of which is selected so that it is accessible through the grain outlet which is normally covered by the hatch 22 (see Figure 4). By removing the hatch 22, the bar 156 can be vigorously shaken from side to side by gripping the handle 158.

The high pressure air in the conduit 86 will be transferred as a series of implosions into the entrance 80 unless steps are taken to vent the rotating compartments in the valve defined by the rotating vanes. To this end a vent 143 is provided as shown in Figure 3 and Figure 6 and for convenience (since the vented air will be dust-laden) the vent 143 communicates with the interior of the main body 16 via a pipe 145 (see Figure 6), the direction of flow of air etc. in the pipe 145 being denoted by arrow 147.

As a further refinement, the air pressure in the rotating compartments of the rotary valve 82 during theirtraversefrom a region of negative pressure (in the compartment 52) to a region of high pressure (in the conduit 86), is equalised by providing a vent 83 in the body of the valve 82 which communicates with the pipeline 102 via a pipe 85. This causes the turbulence (which will occur when the high pressure air enters a compartment containing bulk material and negative pressure air) to occur before the compartment registers with the outlet opening 84 so that the discharge through the latter is not impeded.

The vanes of the rotary valve 82 may to advantage be set at an angle of 5 or thereabouts relative to the axis of the vane carrying shaft 81, so as to reduce the tendency for jamming to occur, as is known in the art.

Turning again to Figure 6, a second pressure relief valve 137 is provided, set to blow at typically 5 p.s.i.g. and a leak-proof butterfly valve 139 is provided to allow the operator to isolate the relief valve 137 for normal blowing duty. In use, the valve 139 is opened (so bringing into operation relief valve 137) when the system is set to load the container 16 via pipeline 104 and inlet 106. The setting of the relief valve is determined by the allowable pressure ratio across the blower 100 and typically for a maximum inlet depression of-5 psig the maximum output pressure allowable will be +5psig. The relief valve 137 is isolated during blowing duty, since in that mode of operation the inlet pressure to the blower will be at approximately atmospheric pressure and therefore the output pressure in line 102 can be allowed to rise to as high as 15 psig if desired and to this end relief valve 136 is set to blow at the maximum desired operating pressure which is typically 12 psig.

Claims (13)

1. A bulk carrier vehicle which includes a bulk carrying container a portion of which is strengthened to allow at least a partial vacuum to be generated therein, discharge means associated with the compartment for collecting bulk material from a low region in the compartment and discharging the collected material into a conduit, means for creating at least a partial vacuum within the said compartment and for generating a through flow of air through the said conduit, inlet means to the said compartment and conduit means attachable thereto for conveying to the compartment bulk material under the action of the suction created by the vacuum generated within the compartment, and outlet means associated with the conduit through which the discharged material in the conduit is conveyed.

2. A bulk carrier as claimed in claim 1 in which the means for generating the through flow of air in the said conduit comprises a rotary pump driven by the vehicle engine and the air input to the pump is via the said compartment.

3. A bulk carrier as claimed in claim 1 or 2 in which the compartment includes an air inlet valve which can be opened to allow air to be admitted to the compartment.

4. A bulk carrier as claimed in any of claims 1 to 3 in which filter means is provided within the compartment to prevent the ingress of dirt and dust from the compartment into the input to the blower.

5. A bulk carrier as claimed in any of claims 1 to 4 in which means is provided for shutting off the discharge device from an upper region of the said compartment, so that the discharge device communicates with the remainder of the interior of the bulk carrier, whereby the discharge device can operate in a manner known per se to collect bulk material and convey it into the air stream in the conduit produced by the blower.

6. A bulk carrier as claimed in claim 4 or 5 in which the filter means comprises a plurality of filter bags which communicate with a manifold at the upper end of the chamber and hang down into the chamber

7. A bulk carrier as claimed in claim 6 in which the manifold communicates via a pipe line with the input to the blower.

8. A bulk carrier as claimed in claim 7 in which at least one in-line filter is provided in the pipe line between the manifold and the inlet to the blower to further reduce the risk of dirt or dust entering the inlet to the blower.

9. A bulk carrier as claimed in claim 5 in which the means for shutting off the upper part of the compartment from the discharge unit is operable from outside the bulk carrier and is adjustable between first and second positions in the second of which the discharge unit communicates with the interior of the said compartment and the compartment is sealed off entirely from the remainder of the bulk carrying compartment of the vehicle.

10. A bulk carrier as claimed in any of claims 1 to 9 in which the bulk material inlet into the compartment is located at an elevated position within the compartment so that as the air and bulk material enter the compartment, the air is sucked upwardly through the filter and the bulk material, being more dense, drops downwards to the discharge unit.

11. A bulk carrier as claimed in any of claims 1 to 10 further comprising a pipeline connected between the output of the said conduit and a discharge conduit, communicating with the interior of the bulk carrier, so that bulk material in the said conduit will be blown through the output thereof along the discharge conduit and into the bulk carrier.

12. Apparatus for converting an existing blow discharge bulk carrier comprising, means for providing a strengthened compartment as part of the bulk carrier, means for connecting the said strengthened compartment to the existing discharge device, means for sealing the discharge device from the compartment, means for connecting the discharge device to the interior of the bulk carrier, valve means for controlling the flow of air into the strengthened compartment, further valve means for controlling the inflow of bulk material into the said compartment, and filter means for separating dust and dirt and bulk material from the air entering the compartment and means for conveying filtered air from the compartment to the input to a blower.

13. A bulk carrier constructed arranged and adapted to operate substantially as herein described with reference to the accompanying drawings.

13. Apparatus as claimed in claim 12 further comprising flexible hose means for connecting the output of a conduit means to the interior of the bulk carrier.

14. Apparatus as claimed in claim 12 or 13 for fitting to a bulk carrier which is divided into separate compartments, further comprising conduit means for conveying bulk material into the separate compartments selectively and valve means for controlling the inflow of bulk material into the said separate compartments.

15. A method of filling a bulk carrier with bulk material which can be conveyed in an air stream, comprising the steps of establishing at least a partial vacuum in a sealed compartment which communicates with the conventional discharge device associated with the bulk carrier, causing bulk material to be conveyed into the said compartment from a supply of the said bulk material as a reslt of suction action induced by the partial vacuum in the said compartment, causing the incoming air and bulk material to be separated within the compartment and causing the bulk material to fall within the compartment to be collected by the known discharge device, operating the latter so as to convey the collected bulk material into a conduit, establishing a through flow of air along the conduit and conveying the air and bulk material flowing along the conduit into the bulk carrier to fill the latter.

16. A method as claimed in claim 15 in which the establishment of the partial vacuum is simultaneous with the step of establishing the through flow of air in the conduit by using a common blower.

17. A bulk carrier constructed arranged and adapted to operate substantially as herein described with reference to the accompanying drawings.

New claims or amendments to claims filed on 23.10.79 Superseded claims 1,5,6,7,8,9,10,11,12, 13,14, 15,16 and 17.

New or amended claims: CLAIMS

1. A bulk carrier vehicle which includes a bulk carrying container a portion of which is strengthened to form a compartment and to allow at least a partial vacuum to be generated in the compartment, discharge means associated with the compartment for collecting and discharging bulk material from a low region in the compartment into a conduit, means for creating a vacuum within the said compartment and for generating a through flow of air through the said conduit, inlet means to the said compartment and conduit means attachable thereto for conveying to the compartment bulk material under the action of the suction created by the vacuum generated within the compartment, outlet means associated with the conduit through which the discharged material in the conduit is conveyed and means for shutting off the discharge device from an upper region of the said compartment so that the discharge device communicates with the remainder of the interior of the bulk carrier whereby the discharge device can operate in a manner known per se to collect bulk material and convey it into the air stream in the conduit produced by the blower.

5. A bulk carrier as claimed in claim 4 in which the filter means comprises a plurality of filter bags which communicate with a manifold at the upper end of the chamber and hang down into the chamber.

6. A bulk carrier as claimed in claim 5 in which the manifold communicates via a pipe line with the input to the blower.

7. A bulk carrier as claimed in claim 6 in which at least one in-line filter is provided in the pipe line between the manifold and the inlet to the blower to further reduce the risk of dirt or dust entering the inlet to the blower.

8. A bulk carrier as claimed in claim 4 in which the means for shutting off the upper part of the compartment from the discharge unit is operable from outside the bulk carrier and is adjustable between first and second positions in the second of which the discharge unit communicates with the interior of the said compartment and the compartment is sealed off entirely from the remainder of the bulk carrying compartment of the vehicle.

9. A bulk carrier as claimed in any of claims 1 to 8 in which the bulk material inlet into the compartment is located at an elevated position within the compartment so that as the air and bulk material enter the compartment, the air is sucked upwardly through the filter and the bulk material, being more dense, drops downwards to the discharge unit.

10. A bulk carrier as claimed in any of claims 1 to 9 further comprising a pipeline connected between the output of the said conduit and a discharge conduit, communicating with the interior ofthe bulk carrier, so that bulk material in the said conduit will be blown through the output thereof along the discharge conduit and into the bulk carrier.

11. Apparatus for converting an existing blow discharge bulk carrier comprising means for providing a strengthened compartment as part of the bulk carrier, means for connecting the said strengthened compartment to an existing discharge device, means for sealing the existing discharge device from the compartment, means for connecting the discharge device to the interior of the bulk carrier, valve means for controlling the flow of air into the strengthened compartment, further valve means for controlling the inflow of bulk material into the said compartment, filter means for separating dust and dirt and bulk material from the air entering the compartment, means for conveying filtered air from the compartment to the input to a blower and flexible hose means for connecting the output of a conduit means to the interior of the bulk carrier.

12. Apparatus as claimed in claim 11 for fitting to a bulk carrier which is divided into separate compartments, further comprising conduit means for conveying bulk material into the separate compartments selectively and valve means for controlling the inflow of bulk material into the said separate compartments.