Patent Application
20060120209
The present invention relates to an agitator loading system. Particularly, the present invention relates to the loading of mixture ingredients into an agitator at a concrete batching plant.
Concrete batching plants must adhere to strict statutory requirements regarding the control of environmental conditions. One area that requires particular attention is the loading of mixture ingredients, for use in making concrete, into an agitator.
The mixture ingredients of concrete typically include aggregate, such as sand and gravel, cement and water. Each ingredient is separately stored and delivered to a gob hopper, which feeds the mixture into the loading inlet of an agitator. The loading of the agitator occurs in a loading bay, which is enclosed on three sides, such that the agitator is reversed into the bay. The enclosed loading bay is designed to reduce the amount of dust emission into the surrounding environment. When loading is finished, the agitator truck drives out to allow another agitator to reverse in. As the loading bay is enclosed on three sides, any material or water spilt during the loading process is contained within the loading bay, to be cleaned out periodically.
The agitator loading system in current concrete batching plants is slow, resulting in slow batching times as well as traffic management and agitator maneuverability concerns. Dust emission out of the open end of the loading bay is a problem, as is noise emission. There is a large amount of spillage and waste of the ingredients and water, thus the loading bay needs to be constantly cleaned.
It would be desirable to provide an agitator delivery system that alleviates or overcomes one or more problems associated with known systems.
The present invention provides an agitator loading, including a loading bay, a delivery chute for delivering mixture ingredients from a storage area, and a dust containment apparatus for minimizing dust dispersion during agitator loading.
Preferably, the delivery chute is movable between a retracted position and at least one extended position. The delivery chute may extend between the storage area and an inlet on the agitator, when in the extended position. The delivery chute can have two extended positions, or more than two, which positions the delivery chute at variable heights below the storage area. This variable height delivery chute allows agitators of different heights to all use the one agitator loading system.
The system may include a drip tray. The drip tray is preferably moveable between an extended position beneath the delivery chute and a retracted position during agitator loading.
Advantageously, the dust containment apparatus includes a door for closing one end of the loading bay. Alternatively, two doors may be included for closing both ends of the loading bay. The dust containment apparatus may also include a dust hood. The dust hood is preferably moveable between a retracted position and a lowered position for minimizing dust dispersion during agitator loading. Advantageously, the dust hood extends below the agitator inlet when in the lowered position. The dust containment apparatus may also include an extractor. The inlets of the extractor are preferably located within the dust hood when the dust hood is lowered.
An embodiment of the present invention provides a method for loading an agitator from an agitator loading system, as described above. The method includes the steps of driving the agitator into the loading bay for positioning an inlet on the agitator beneath the delivery chute, extending the delivery chute towards the agitator inlet, causing the dust containment apparatus to be placed into a dust containment configuration, and loading the agitator through the delivery chute into the agitator inlet.
The step of extending the delivery chute may include moving the delivery chute from a retracted position to at least one extended position.
The system may include a drip tray, whereby the drip tray is retracted from beneath the delivery chute before the delivery chute is extended.
The dust containment apparatus may include a door, whereby the step of effecting operation of the dust containment apparatus may include the step of lowering the door once the agitator inlet is placed in position beneath the delivery chute. The dust containment apparatus may also include a dust hood, whereby the step of effecting operation of the dust containment apparatus may include the step of lowering the dust hood once the agitator inlet is placed in position beneath the delivery chute. The dust hood may be extended below the agitator inlet.
The dust containment apparatus may also include an extractor, whereby the step of causing the dust containment apparatus to be placed into a dust containment configuration includes the step of activating the extractor.
The invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
An agitator loading system 20 is shown in
The delivery chute 24 is shown in FIGS. 4 to 6. Delivery chute 24 is attached to the bottom of gob hopper 18 and is in the form of a tubular rubber sock. Delivery chute 24 can be moved between a retracted position and a number of extended positions. In the retracted position, the bottom 30 of delivery chute 24 is positioned against the top 32 of delivery chute 24. The retracted position allows the agitator 22 to be driven underneath the delivery chute 24 and the inlet 28 to be positioned in line with the delivery chute 24. The delivery chute 24 has two extended positions, the fully extended position shown in FIGS. 4 to 6 and a position in which bottom 30 is retracted part of the way to the top 32. The variable heights of the delivery chute 24 allow different sized agitators 22 to use the one agitator loading system 20. There are typically two sized agitators 22, the standard and the mini-mixer. In other embodiments of the invention, there may be more than two extended positions.
The delivery chute 24 is suspended from a plate 36, onto which gob hopper 18 is situated. The bottom 30 of the delivery chute 24 is attached to a plate and frame assembly 38. Part way along the delivery chute 24 there is attached a middle plate and frame assembly 34. Both frame assemblies 34, 38 are suspended by wire ropes 40 to a lifting assembly 42. When activated, wire ropes 40 are retracted by lifting assembly 42 and plates 34, 38 are lifted to the desired position. As the delivery chute 24 is a rubber sock, as the plates 34, 38 are lifted, the delivery chute 24 is flexible enough for the delivery chute 24 to be collapsible.
The system 20 also includes a drip tray 44, which is positioned beneath delivery chute 24 when system 20 is not in use, as shown in FIGS. 9 to 11. The drip tray 44 catches any excess mixing ingredients that may escape from the delivery chute 24 once the loading of the agitator 22 has finished. When the delivery chute 24 is required for loading of the agitator 22, the drip tray can be retracted, by sliding along rails 58, to allow the mixing ingredients to enter the inlet 28 of the agitator 22.
The dust containment apparatus 26 illustrated in
The dust containment apparatus 26 also includes a dust hood 48, which is moveable between a retracted position and a lowered position (as shown in
The dust containment apparatus 26 also includes an extractor 60, as shown in
As shown by the flow chart in
The mixture ingredients of concrete typically include aggregate, such as sand and gravel, cement and water. Aggregate is delivered via conveyor 10 and is stored in storage hopper 66. A selected amount of aggregate is delivered into gob hopper 18, along with water from the water tank 14. Cement is weighed in weigh hopper 64, before being delivered into gob hopper 18.
Once the driver presses the button, the drip tray 44 retracts at step 102, and the delivery chute 24 is extended at step 103 towards the agitator inlet 28. The dust containment apparatus 26 is also caused to be placed in a dust containment configuration, such that the door 46 is lowered at step 104 and the dust hood 48 is lowered at step 105. The measured amount of mixture ingredients are released from the gob hopper 18 and the agitator is loaded at step 106 with the mixture ingredients through the delivery chute 24 into the inlet 28. Once loading is completed, the dust hood 48 is retracted at step 107, the door 46 is lifted at step 108 and the delivery chute 24 is lifted at step 109. The drip tray is then extended at step 110 and the agitator 22 is driven out of the delivery bay 16 at step 111.
One of the advantages of the agitator loading system 20 is the reduction in dust emissions into the surrounding environment. The system is efficient and increases batching times and the drive through loading bays increase traffic flow within the plant and reduce traffic management issues.
It will be understood that the invention disclosed and defined in this specification extends to all alternative combinations of two or more of the individual features mentioned or evident from the text or drawings. All of these different combinations constitute various alternative aspects of the invention.
Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.
