Method and apparatus for metering and blending different material ingredients

• US 5,148,943 A
• Filed: 06/17/1991
• Issued: 09/22/1992
• Est. Priority Date: 06/17/1991
• Status: Expired due to Fees

• Current Assignee: Hydreclaim Corporation (ACS Group, Inc.)
• Original Assignee: Hydreclaim Corporation (ACS Group, Inc.)
• Inventors: Moller, Richard W.
• Primary Examiner(s): Shaver, Kevin P.
• Application Number:
  US07/716,084
• Time in Patent Office: 463 Days
• Field of Search: 222/1, 222/64, 222/55, 222/56, 222/57, 222/58, 222/77, 222/71, 222/135, 222/138, 222/139, 222/142, 222/145, 177/1, 177/50, 177/70, 177/105, 425/135, 425/145, 425/148, 364/479, 364/567, 364/571.04, 364/571.05, 364/571.06
• US Class Current: 222/1
• CPC Class Codes: B01F 23/60 Mixing solids with solids
• CPC Class Codes: B01F 35/20 Measuring; Control or regulation
• CPC Class Codes: B01F 35/71 Feed mechanisms with proportioning B01F35/80
• CPC Class Codes: B01F 35/712 for feeding fluids
• CPC Class Codes: B01F 35/71775 using helical screws
• CPC Class Codes: B01F 35/7547 using valves, gates, orifices or openings
• CPC Class Codes: B01F 35/832 Flow control by weighing
• CPC Class Codes: B29B 7/603 in measured doses, e.g. proportioning of several materials
• CPC Class Codes: B29B 7/728 Measuring data of the driving system, e.g. torque, speed, power, vibration B29B7/724 takes precedence
• CPC Class Codes: B29B 7/78 by gravity, e.g. falling particle mixers
• CPC Class Codes: B29C 31/02 Dispensing from vessels, e.g. hoppers into a mould cavity B29C31/04; large containers characterised by discharge means B65D88/28, B65D88/54
• CPC Class Codes: B29C 31/06 in measured doses , e.g. by weighting feeding mixers with measured doses B01F35/714, B01F35/882, B29B7/24, B29B7/603
• CPC Class Codes: B29C 31/10 of several materials
• CPC Class Codes: B29C 48/00 Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor extrusion blow-moulding B29C49/04
• CPC Class Codes: B29C 48/03 characterised by the shape of the extruded material at extrusion
• CPC Class Codes: B29C 48/2692 Material change
• CPC Class Codes: B29C 48/285 Feeding the extrusion material to the extruder
• CPC Class Codes: B29C 48/286 Raw material dosing
• CPC Class Codes: B29C 48/288 in solid form, e.g. powder or granules
• CPC Class Codes: G01G 19/343 involving digital counting
• CPC Class Codes: G01G 19/382 : involving digital counting

Abstract

A plurality of individual plastic material ingredients are metered from respective individual material hoppers at controllable individual discharge rates, blended, and delivered to a common hopper. The blend of plastic material ingredients in the common hopper is discharged to an extruder or other material processing machine. The material processing rate of the processing machine is determined based on the sum of the discharge rates of the individual ingredients to the common hopper plus or minus the discharge rate of the blend from the common hopper to the processing machine. The discharge rates of the individual material ingredients from the individual hoppers to the common hopper is controlled as needed to maintain a preset recipe of the blend at the determined material processing rate of the processing machine.

Claims

1. A method of metering different material ingredients for discharge to a material processing machine, comprising:

delivering to a common hopper a plurality of individual material ingredients at controllable individual material discharge rates,

discharging material from said common hopper to said processing machine at a discharge rate,

determining loss of weight of material in said hopper due to discharge of material therefrom,

determining the material processing rate of the processing machine from the sum of the material discharge rates of the ingredients to the common hopper and the discharge rate of the material from the common hopper to the processing machine, and

controlling the material discharge rates of the ingredients to the common hopper in response to said determined material processing rate as needed to maintain a preset recipe of said blended ingredients at said determined material processing rate.

2. The method of claim 1 including adjusting the material discharge rates of the ingredients to maintain a substantially constant weight thereof in the common hopper at said material processing rate.

3. The method of claim 2 including adjusting the material discharge rates of the ingredients to stabilize the weight thereof in the common hopper at the center of a preset narrow change of weight range at said material processing rate.

4. A method of metering and blending different plastic material ingredients for discharge to an extrusion machine, comprising:

metering to a common hopper a plurality of individual plastic material ingredients at controllable individual material discharge rates,

blending the ingredients discharged from the individual material hoppers to form a blend in the common hopper,

discharging the blended materials from said common hopper to said extrusion machine at a discharge rate,

determining loss of weight of the blended materials in said common hopper due to discharge of the blended materials to the extrusion machine,

determining the extrusion rate of the extrusion machine from the sum of the material discharge rates of the ingredients to the common hopper and the discharge rate of the blended materials from the common hopper to the extrusion machine, and

controlling the material discharge rates of the ingredients to the common hopper in response to said determined extrusion rate as needed to maintain a preset recipe of the blended ingredients at said determined extrusion rate.

5. The method of claim 4 including adjusting the material discharge rates of the ingredients to maintain a substantially constant weight of the blended materials in the common hopper at said extrusion rate.

6. The method of claim 5 including adjusting the material discharge rates of the ingredients to stabilize the weight of the blend in the common hopper at a center point of a preset narrow weight change range at said extrusion rate.

7. Apparatus for metering different material ingredients for discharge to a material processing machine, comprising:

a plurality of metering devices for providing a controlled discharge rate of individual material ingredients, each of said metering devices comprising an individual material hopper for containing the material ingredient to be metered, first weighing means operably associated with each individual material hopper for detecting loss in weight of the material ingredient therein, a driven discharge device operably associated with each material hopper for discharging the material ingredient therefrom, and computer control means coupled to the weighing device for determining a material discharge rate and operably associated with the driven discharge device of each hopper for controlling the material discharge rate thereof,

a common hopper for receiving the ingredients discharged by the metering devices,

second weighing means operably associated with the common hopper for detecting a change in weight of the ingredients therein during discharge from the common hopper to the material processing machine, and

a master computer control unit coupled to said individual computer control devices and to said second weighing means, said master computer control device being operative to determine the material processing rate of said machine based on the sum of said material discharge rates from the metering devices to the common hopper plus or minus the discharge rate of the ingredients from the common hopper to the processing machine and to control the material discharge rates of the metering devices as needed to maintain a preset recipe of said ingredients at said determined material processing rate.

8. The apparatus of claim 7 wherein the first weighing means comprises a load cell supporting a respective material hopper.

9. The apparatus of claim 7 wherein the discharge device of each metering device comprises a variable speed motor-driven auger.

10. The apparatus of claim 9 wherein the speed of each motor-driven auger is controlled by said master computer control unit via the associated computer control device so as to control the material discharge rate of the metering device.

11. The apparatus of claim 7 including means for receiving and mixing the ingredients discharged by the metering devices to form a blend received by the common hopper.

12. The apparatus of claim 7 wherein the second weighing means comprises a load cell supporting the common hopper.

13. The apparatus of claim 7 wherein the master computer control device is operative to control the material discharge rates of the metering devices so as to maintain a substantially constant weight of the ingredients in the common hopper at said material processing rate.

14. Apparatus for metering and blending different plastic material ingredients for discharge to an extrusion machine, comprising:

a plurality of metering devices for providing a controlled discharge rate of individual plastic material ingredients, each material metering device comprising an individual material hopper for containing the material ingredient to be metered, first weighing means operably associated with each individual material hopper for detecting a loss in weight of the ingredient therein, a motor-driven discharge device operably associated with each material hopper for discharging the ingredient therefrom, and a computer control device coupled to the first weighing means for determining a material discharge rate and operably associated with the motor-driven discharge device of each hopper for controlling the material discharge rate thereof,

a cascade chamber for receiving and mixing the ingredients discharged by the metering devices to form a blend,

a common hopper for receiving the blend of ingredients from the cascade chamber,

second weighing means operably associated with the common hopper for detecting a change in weight of the blend therein during discharge from the common hopper to the extrusion machine,

a master computer control unit coupled to said individual computer control devices and to said second weighing means, said master computer control device being operative to determine the extrusion rate of said machine based on the sum of said material discharge rates from the metering devices to the common hopper plus or minus the discharge rate of the blend from the common hopper to the extrusion machine and to control the material discharge rates of the metering devices to the common hopper as needed to maintain a preset recipe and substantially constant weight of said ingredients in the common hopper at said determined extrusion rate.