Portable cement mixing apparatus with precision controls
10695950 ยท 2020-06-30
Assignee
Inventors
Cpc classification
B28C7/0422
PERFORMING OPERATIONS; TRANSPORTING
B28C7/02
PERFORMING OPERATIONS; TRANSPORTING
B28C7/0436
PERFORMING OPERATIONS; TRANSPORTING
International classification
B28C7/04
PERFORMING OPERATIONS; TRANSPORTING
B28C7/02
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A quality assurance system for mixing a slurry comprising at least water or other liquid and at least one flowable wet or dry mass, such as cement, sand or other suitable component, has computerized control over the loading of ingredients and has an accurate and broadly variable speed control of the loading of the ingredients. The mixing chamber has scales that provide a signal indicating the current weight of an ingredient in the mixing chamber. As the desired weight of an ingredient is added to the mixing chamber, the computer slows and then stops the inflow of the current ingredient being loaded via broadly variable control of the loading of the ingredients. The broadly variable control of the loading rate of the ingredients allows more accurate control of the final weight of each ingredient added. Further, a damping period allows system vibrations to dissipate, allowing highly accurate weights to be measured. Accurate records of the addition of each ingredient are maintained using the internal computer that controls the invention. The combination of highly accurate control over the input of materials added to the mixing chamber as well as the maintenance of permanent records concerning each batch of cementitious slum made allows the production of precision batches of final products to meet exacting specifications needed in both ordinary projects and highly specialized projects requiring cementitious products. Data recorded during production operations further allow accurate identification of manpower needs of projects and allow owners/operators at job sites to record, control, predict and manage production costs and manpower needs. All recorded data is transmitted to an offsite location for management to use as needed for quality and management control and can be transmitted at any time or hatch interval desired by management.
Claims
1. An apparatus for producing a cementitious slurry at a remote work site from a plurality of ingredients comprising: a platform a plurality of storage containers for ingredients of a cementitious slurry supported by said platform; a mixing chamber further comprising mixing blades and able to receive an ingredient from each storage container, said mixing chamber having four feet; a strain gauge load cell positioned between each of said feet of said mixing chamber and said platform, each strain gauge load cell affixes said mixing chamber to said platform, each strain gauge load cell is configured to communicate weight data and said strain gauge load cells are suitable for weighing the amount of each individual ingredient delivered to the mixing chamber in real time; a plurality of conveyors suitable to convey cementitious slurry ingredients from each of the plurality of storage containers to the mixing chamber; a water tank supported by said platform; a pump within said water tank; a hose having a first end attached to said pump provides fluid communication between said water tank and said mixing chamber; a nozzle attached to a second end of said hose conveys water into said mixing chamber; at least one hydraulic valve carried by said hose, said hydraulic valve located between said pump and said nozzle; and, an operating system configured to receive weight data from each of said strain gauge load cells and to cause, control and monitor the rate of conveyance of individual ingredients from each of the plurality of storage containers and water tank into the mixing chamber and to end the conveyance of individual ingredients from each of the storage containers and water tank by accurately monitoring the weight of each ingredient in the mixing chamber as reported by said strain gauge load cells to said operating system and said operating system also configured to account for the weight of water emitted from said nozzle but not yet in said mixing chamber.
2. The apparatus of claim 1, further comprising: a holding chamber, said holding chamber in fluid communication with said mixing chamber; a holding chamber scale, said holding chamber scale configured to communicate weight data to said operating system; and, a progressive cavity pump located in said holding chamber, said progressive cavity pump controlled by said operating system in which the operating system causes the input of cementitious slurry ingredients at different speeds depending on the weight of slurry ingredients in the mixing chamber.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF THE DRAWINGS
(13) The invention is capable of mixing at a worksite high quality slurry for use in various areas of the construction industry in which it is necessary to know the ingredients of the slurry to a high accuracy as well as to create and maintain a permanent, portable or transmittable record of the manufacturing of the slurry for quality assurances purposes.
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(15) The hose 104 is fluidly connected from the tank 103 to the opening 102 of the mixing chamber 101, with the nozzle 108 of the hose removably affixed to the top of the mixing chamber 101 so as to allow water or other liquid to flow into the mixing chamber 101 through the opening 102. In an alternate embodiment, the nozzle 108 may be placed through a wall of the mixing chamber 101 at any unobstructed position to allow water to be introduced into the mixing chamber 101 as needed.
(16) Referring to
(17) Referring to
(18) During a production run, the operating system typically determines the amount of slurry to be left in the mixing chamber 101, which may be any amount of the previous batch sufficient to aid subsequent operations. However, in alternate embodiments of the invention, the determination of the amount of slurry left in the mixing chamber 101 from a previous batch may be automatically determined based on environmental conditions or production needs and as determined, by sensors, such as temperature sensors, moisture sensors, sensors for determining the density of a slurry or the like. A failure to list a type of sensor or the data a sensor might detect is not a limiting factor in alternative embodiments of the invention. Any suitable sensor measuring any suitable quality of the slurry or the apparatus may be used.
(19) Referring to
(20) In an operational run, a worker either selects a pre-programmed recipe or enters an ingredient list, desired weights, and mixing time into the operating system 301 and starts the operation of the apparatus. The operating system 301 activates the scales 401 to set the tare weight of the mixing chamber 101. Mixing of slurry begins when the pump in the water tank. 103 is activated by the operating system 301, starting the flow of water into the mixing chamber 101. While other liquids may be used, water is the typical liquid ingredient and will be described in this exemplary embodiment. At the start of the flow of water, the hydraulic water pump in the water tank 103 is activated by the operating system 301 for a fast flow of water. Valves are opened to permit the pump to cause a high rate of flow of water into the mixing chamber 101. The operating system 301 measures the weight of water in the mixing chamber 101 using the set of scales 401 in real time. A software algorithm therefrom determines the weight of water accurately. The operating system 301 uses that measurement to determine whether to maintain the rate of water flow into the mixing chamber 101 or to modify it.
(21) When the weight of the water in the mixing chamber 101 reaches a preprogrammed, predetermined threshold as set in the operating system 301 software, the operating system 301 sends a signal to the hydraulic control valves controlling the pump to slow the input rate to a slower but still known rate of input. Real time weighing of the water in the mixing chamber 101 by the scales 401 is continuous throughout. When the weight of the water in the mixing chamber 101 reaches final threshold determined by the recipe, the operating system 301 signals the hydraulic, valves to stop the pump. The operating system 301 software is configured to account for the amount of water which has been emitted from the nozzle 108 but which has not yet fallen into the an chamber 101 to be weighed. Thus, the operating system 301 can be seen to anticipate this additional amount of water not yet measured in the mixing chamber 101 following shut off of the pump and closing of the valves. The weight of the water in the mixing chamber 101 which causes the signal to shut off the pump is thus:
(total weight of water desired as an ingredient)(weight of water in freefall between nozzle and mixing chamber)=(weight of water sufficient to signal pump shut-off).
(22) By this method, after the shutting off of the pump and the weighing of the water in the mixing chamber 101, the total weight of water in the mixing chamber 101 will be within a specified, low tolerance of the specified amount programmed into the operating system 301.
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(24) As further described in
(25) It is thus seen that the operating system 301 typically controls the rate of input of an ingredient, currently, water, in a trinary system-off fast input and slow input rates. It is noted, however, that the operating system 301 allows a fully variable range of speeds for inputted ingredients. The fast setting may vary, depending on need, from Y gallons per minute to Y gallons per minute, to Y gallons per minute, or any rate in-between and with the Y, Y and Y values determined on conditions such as pump or valve capabilities, worksite conditions, slurry type and so forth. Similarly, lower rates of input for the Z, Z and Z rates of flow are fully variable except that a given Y value will always be greater than its accompanying Z value. The alternative, in which Y<Z is possible, but of no practical value. Rates of change between a Y rate and a Z rate may also be controlled by the operating system along any rate of change.
(26) The operating system 301 further creates and stores data in memory 1103 relative to each production hatch during operation, including a batch identifier, worksite information, the weight of the each ingredient added to the mixing chamber in the batch, the identity of each ingredient in the batch, mixing time and other information useful for quality control.
(27) Following completion of the addition of water to the mixing chamber 101, the amount of water is weighed by the following process: the speed of the engine operating the apparatus is maintained at a constant rate and the mixing blades 107 are maintained at a slow speed. The operating system 301 then measures the weight of the water in the mixing chamber 161 for a predetermined period, typically 3 seconds. By allowing a known level of systemic vibration only to be accounted for, the actual weight of the water is determinable to high precision. Other sources of vibration and weighing error are damped from the system, such that a more accurate measure of the weight is obtained. The weight of the water in the mixing chamber 101 is confirmed to have held steady for the waiting period and then recorded. This process is also depicted in
(28) Still referring to
(29) At time A, a similar process is followed for the loading of the filler, as depicted from time A though time F, with a suitable period for assuring and recording the weight of the filler in it like manner.
(30) The lengths of the pauses have been programmed to allow internal and systemic vibrations to dissipate from the apparatus. In doing so, a far more accurate determination of the weight of each ingredient can be made. Pauses of approximately 2 seconds to approximately 10 seconds are also typical.
(31) Having added the water, the next ingredient, typically a binder in the form of a cementitious powder, may be added. Referring to
(32) The base of the bin 701 is attached to a coupler 706 for connecting to the bin 701 to a powder delivery tube 704 for delivering the cementitious powder into the mixing chamber 101. Within the powder delivery tube 704 is an auger 802 of known design powered by a motor and controlled by the operating system 301. An exit port 708 distal on the powder delivery tube 704 to the coupler 706 allows the cementitious powder to exit the auger 802 from above the mixing chamber opening 102 to allow infall of the cementitious powder into the mixing chamber 101.
(33) The bin 701 may be filled by workers by emptying either bulk or bagged quantities of a desired cementitious powder into the bin.
(34) Upon inputting a recipe of ingredients for a batch of slurry into the operating system 301, and upon completion of inputting water in the mixing chamber 101, the operating system 301 again sets the tare weight to zero, indicting no amount of the next ingredient, in this case the cementitious powder, has been added to the mixing chamber 101. Then, the operating system signals the hydraulic valves to operate the motor for the auger 802 to run. The cementitious powder in the bin 701 is carried along the auger 802 disposed within the powder delivery tube 704 and infalls into the mixing chamber 101 via, the exit port 708. As with the water, the operating system 301 weighs the input amount of cementitious powder in real time using the scales 401. Referring to
(35) The arbitrary rate of Y gallons per minute for water does not connote to the arbitrary rate of Y pounds per minute for cementitious powder. The rates are identified for scale only. Any rate of input for any ingredient in a portable mixing apparatus may be used.
(36) When the pre-set threshold is reached, the operating system 301 signals the hydraulic valves to operate the motor to slow the auger 802 such that the rate of input of the cementitious powder is slowed to arbitrary rate Z, in which Y>>Z. As with the water input, the operating system 301 software is configured to allow for a known amount of cementitious powder which has fallen from the exit part 708 but not yet landed in the mixing chamber 101 so as to determine an accurate time at which to stop all inflow into the mixing chamber 101. By this method, the quantity of cementitious powder placed into the bin 701 is known to within a narrow tolerance. When the pre-set final threshold weight of cementitious powder in the mixing chamber 101 is reached, the operating system 301 signals the hydraulic valves to stop the augur 802.
(37) During the process of adding the cementitious powder to the mixing chamber 101, the operating system 301 directs and controls the movement of the mixing blades 107, also as depicted in
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(39) An inventive element of the invention is the ability to input multiple ingredients for cementitious slurry in which a highly accurate weight of each ingredient is provided while allowing a high rate of input for each ingredient, such that said high rates of input of each ingredient can be separately and variably controlled as to need for an individual batch of cementitious slurry.
(40) Referring now to
(41) Upon inputting of the ingredients for a batch of slurry into the operating system 301, and upon completion of inputting water in the mixing chamber 101, and upon completion of inputting the cementitious powder into the mixing chamber 101, the operating system 301 again sets the tare weight to zero, indicting no amount of the next ingredient, in this case the filler, has been added to the mixing chamber 101. Then, the operating system signals the hydraulic valves to operate the motor for the conveyor belt 908 to start. The filler passes through the variably openable port 1010, falls upon the conveyor belt 908 and is carried on the conveyor belt 908 until it infalls into the mixing chamber 101. As with the water, the operating system 301 weighs the input amount of filler in real time using the scales 401. As with the water, at first the rate of input of the filler is at a high rate of speed (here again identified as an arbitrary V pounds per minute) until the weight of the filler in the mixing chamber 101 reaches a pre-set threshold. At that time, the operating system 301 signals the motor to slow the conveyor belt 908 such that the rate of input of the aggregate is slowed to arbitrary rate Z, in which Y>Z. As with the water input, the operating system 301 software is configured to allow for a known amount of filler which has fallen from the conveyor belt 908 into the mixing chamber 101 but not yet landed in the mixing chamber 101 so as to determine an accurate time at which to stop all inflow into the mixing chamber 101 and to ensure that a highly accurate amount of filler is loaded into the mixing chamber 101.
(42) During the process of adding the filler to the mixing chamber 101, the operating system 301 directs the hydraulic valves to control the movement of the mixing blades 107. As with the loading, of cementitious binder, the loading of filler into the hopper 901 may be performed by workers placing bulk or bagged filler into the hopper 901.
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(44) Referring to
(45) Each of the storage containers for the slurry ingredients, i.e. the tank 103, cementitious powder bin 701 or filler hopper 901, are configured on the steel beam, flatbed trailer 100 to allow the addition of additional ingredients to be stored for use. As such, during the mixing of a batch of cementitious slurry, as or after water is conveyed from the tank 104 to the mixing, chamber 101, additional water may be pumped to the tank 104 from an external source. Likewise, as or after cementitious powder is conveyed from the bin 701 to the mixing chamber 101, additional cementitious powder may be added by workers loading bags of cementitious powder from bags or bulk loaded, through the top of the bin 701. Similarly, workers may add additional reserves of filler into the hopper 901 as or after the conveyance of filler from the hopper 901 to the mixing chamber 101. By this, the invention is enabled, in part, to allow for continual batch processing.
(46) The mixing blades continually run while the ingredients are delivered into the mixing chamber 101. After all ingredients have been delivered, weighed and recorded, the mixing blades 107 in the mixing chamber 101 mix the ingredients at a faster rotation for the predetermined time. A typical mixing time is about 20 seconds, but any suitable time may be used.
(47) Referring again to
(48) In determining the amount of slurry to be removed from the mixing chamber 101 to the holding chamber 305, the operating system uses the scales 401 to weigh the amount of slurry remaining in the mixing chamber 101. When the pre-set amount of slurry has been removed to the holding chamber 305, the operating system 301 closes the port on the side of the mixing chamber, stopping removal of slurry. The next batch of slurry may then be prepared following the protocol above.
(49) The holding chamber 305 is also placed on a scale (not depicted) to measure its weight in real time. This scale in connected through wiring to the operating system. The operating system 301 will not allow the mixing chamber to dump slurry into the holding chamber 305 until the progressive cavity pump has pumped enough slurry out of the holding chamber 305 to allow enough room for the slurry to be dumped from the mixing chamber 101.
(50) Referring to
(51) The operating system 301 stores all information regarding the batch made, including the weight of each ingredient and mixing time in permanent storage. Stored data is maintained in the operating system 301 or can be transmitted or downloaded as needed. For example, and without limitation, a record of each batch for a project can be saved to removable storage. Critically, given the correspondence between ingredients ratios, mixing, times and strength or other qualities of the poured slurry, the downloaded information creates a permanent record of the product characteristics of the batches, in the event a problem arises with the as-poured product, the data constitute a permanent quality assurance record suitable to support a warranty on the batches produced.
(52) Also, a remote control can be used to remotely transmit a signal to the progressive cavity pump to stop the pump in the middle or end of an application and/or installation of a batch of slurry.
(53) In addition to providing information about art individual hatch, the data storage capabilities of the operating system allow management oversight at each project worksite. In addition to details of each batch of slurry produced during the workday, extractable and/or storable data includes the times during, the day during which the apparatus was used, notification if the system was down or unused for any amount of time during a work day, when each batch was completed during the work day, the total amount of each ingredient, in pounds, bags, gallons or otherwise, used during a day. Other operation data obtained, stored and transmitted can include information concerning power consumption of the apparatus, such as the RPM of the engine providing power to the apparatus or the total amount of product produced by the apparatus each day.
(54) By the invention, full control of all aspects of slurry production is established and maintained. Further, by the invention, a permanent, distributable quality assurance record of all production parameters is created and maintained.