초록 ▼

An improved volumetric concrete mixing system and method of the present invention utilizes load cells for measuring weight loss from the aggregate and cement bins. Load cells may also be used for measuring weight loss from the water tank. The load cells provide input data corresponding to the weight

An improved volumetric concrete mixing system and method of the present invention utilizes load cells for measuring weight loss from the aggregate and cement bins. Load cells may also be used for measuring weight loss from the water tank. The load cells provide input data corresponding to the weight loss of each container to a controller which automatically adjusts the delivery of ingredients to a mixing boot so as to achieve a desired concrete mix ratio.

대표청구항 ▼

1. A volumetric concrete mixing method, comprising: delivering aggregate from an aggregate bin onto an aggregate conveyor;delivering sand from a sand bin onto a sand conveyor;the aggregate and sand conveyors being arranged side-by-side and being operative independent of one another;delivering cement

1. A volumetric concrete mixing method, comprising: delivering aggregate from an aggregate bin onto an aggregate conveyor;delivering sand from a sand bin onto a sand conveyor;the aggregate and sand conveyors being arranged side-by-side and being operative independent of one another;delivering cement from a cement bin onto at least one of the aggregate and sand conveyors;the aggregate, sand and cement bins being independently mounted on a volumetric concrete mixing truck;transporting the aggregate, sand and cement on the conveyors to a mixing boot on the end of the truck;adding water from a water tank on the truck to the mixing boot;mechanically mixing the aggregate, sand, cement and water in the boot to produce a mixed concrete slurry ready for pouring at a job site;weighing the loss in weight from the bins and the tank using load cells to measure the aggregate, sand, cement and water in the concrete slurry;weighing the aggregate weight loss with a first load cell, weighing the sand weight loss with a second load cell, weighing the water weight loss with a third load cell, and weighing the cement weight loss with a fourth load cell;weighing the bins separately to determine the weight loss of aggregate, sand, water, and cement, respectively;the load cells for each bin and the tank being independent of one another; andadjusting the supply of aggregate, sand, cement, and/or water in response to weight data from the four load cells to achieve a desired concrete mixture specification;wherein a controller automatically calibrates process equipment including bin gate sizes, conveyors and pumps for a given concrete mix ratio. 2. The method of claim 1 wherein the slurry is made at the job site. 3. The method of claim 1 wherein the weighing steps are performed at the job site. 4. The method of claim 1 further comprising inputting data corresponding to the weight loss into a controller and adjusting the delivery of aggregate and/or cement to achieve the desired mixture specification. 5. The method of claim 1 wherein the adjustment includes changing the delivery rate of the aggregate, sand, cement and/or water to the boot. 6. The method of claim 1 wherein the adjustment includes changing the discharge rate of the aggregate, sand, cement, and/or water from the respective bins and/or tank. 7. The method of claim 1 wherein the adjustment includes changing the speed of one or more of the conveyors. 8. The method of claim 1 further comprising a gate on each of the bins and on the tank, and the adjustment including changing the position of one or more of the gates. 9. The method of claim 1 further comprising a gate on each of the bins and on the tank, and a controller operatively connected to the load cells, the gates and the conveyors, and wherein the adjustment includes receiving data at the controller from the load cells and providing feedback from the controller to the gates and/or the conveyors. 10. The method of claim 1 further comprising preprogramming a controller for a selected concrete mix specification having a specific weight for each of the aggregate, sand, cement and water components, and the adjustment being automatically made by the controller if the weights sensed by the load cells do not match the preprogrammed weights. 11. A volumetric concrete mixing method, comprising: depositing sand and aggregate from independent sand and aggregate bins on a truck frame onto independent sand and aggregate conveyors, respectively, running side by side and rearwardly;depositing cement from an independent cement bin on the truck frame to one of the sand and aggregate conveyors;discharging the sand, aggregate and cement from the conveyors into a mixing boot at the rear of the truck frame;adding water from an independent tank on the truck frame into the mixing boot;mixing the sand, aggregate, cement and water with an auger in the mixing boot to produce a concrete slurry ready for pouring;discharging the slurry from the mixing boot;separately weighing the sand, aggregate and cement bins and the water tank;generating weight data for the sand, aggregate, cement and water; andcontrolling the mixture of the sand, aggregate, cement and water in response to the weight data without monitoring the discharged slurry;wherein a controller automatically calibrates process equipment including bin gate sizes, conveyors and pumps for a given concrete mix ratio. 12. The method of claim 11 further comprising separately adjusting the speed of the sand and aggregate conveyors. 13. The method of claim 1 wherein the adjustment step is performed without monitoring the mixed concrete slurry. 14. The method of claim 1 wherein the adjustment step is performed independently from the mixing step.